xref: /vim-8.2.3635/src/fileio.c (revision 723d165c)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * fileio.c: read from and write to a file
12  */
13 
14 #include "vim.h"
15 
16 #if defined(__TANDEM) || defined(__MINT__)
17 # include <limits.h>		/* for SSIZE_MAX */
18 #endif
19 
20 #if defined(HAVE_UTIME) && defined(HAVE_UTIME_H)
21 # include <utime.h>		/* for struct utimbuf */
22 #endif
23 
24 #define BUFSIZE		8192	/* size of normal write buffer */
25 #define SMBUFSIZE	256	/* size of emergency write buffer */
26 
27 /* Is there any system that doesn't have access()? */
28 #define USE_MCH_ACCESS
29 
30 static char_u *next_fenc(char_u **pp);
31 #ifdef FEAT_EVAL
32 static char_u *readfile_charconvert(char_u *fname, char_u *fenc, int *fdp);
33 #endif
34 #ifdef FEAT_VIMINFO
35 static void check_marks_read(void);
36 #endif
37 #ifdef FEAT_CRYPT
38 static char_u *check_for_cryptkey(char_u *cryptkey, char_u *ptr, long *sizep, off_T *filesizep, int newfile, char_u *fname, int *did_ask);
39 #endif
40 static int set_rw_fname(char_u *fname, char_u *sfname);
41 static int msg_add_fileformat(int eol_type);
42 static void msg_add_eol(void);
43 static int check_mtime(buf_T *buf, stat_T *s);
44 static int time_differs(long t1, long t2);
45 
46 #define HAS_BW_FLAGS
47 #define FIO_LATIN1	0x01	/* convert Latin1 */
48 #define FIO_UTF8	0x02	/* convert UTF-8 */
49 #define FIO_UCS2	0x04	/* convert UCS-2 */
50 #define FIO_UCS4	0x08	/* convert UCS-4 */
51 #define FIO_UTF16	0x10	/* convert UTF-16 */
52 #ifdef MSWIN
53 # define FIO_CODEPAGE	0x20	/* convert MS-Windows codepage */
54 # define FIO_PUT_CP(x) (((x) & 0xffff) << 16)	/* put codepage in top word */
55 # define FIO_GET_CP(x)	(((x)>>16) & 0xffff)	/* get codepage from top word */
56 #endif
57 #ifdef MACOS_CONVERT
58 # define FIO_MACROMAN	0x20	/* convert MacRoman */
59 #endif
60 #define FIO_ENDIAN_L	0x80	/* little endian */
61 #define FIO_ENCRYPTED	0x1000	/* encrypt written bytes */
62 #define FIO_NOCONVERT	0x2000	/* skip encoding conversion */
63 #define FIO_UCSBOM	0x4000	/* check for BOM at start of file */
64 #define FIO_ALL	-1	/* allow all formats */
65 
66 /* When converting, a read() or write() may leave some bytes to be converted
67  * for the next call.  The value is guessed... */
68 #define CONV_RESTLEN 30
69 
70 /* We have to guess how much a sequence of bytes may expand when converting
71  * with iconv() to be able to allocate a buffer. */
72 #define ICONV_MULT 8
73 
74 /*
75  * Structure to pass arguments from buf_write() to buf_write_bytes().
76  */
77 struct bw_info
78 {
79     int		bw_fd;		/* file descriptor */
80     char_u	*bw_buf;	/* buffer with data to be written */
81     int		bw_len;		/* length of data */
82 #ifdef HAS_BW_FLAGS
83     int		bw_flags;	/* FIO_ flags */
84 #endif
85 #ifdef FEAT_CRYPT
86     buf_T	*bw_buffer;	/* buffer being written */
87 #endif
88     char_u	bw_rest[CONV_RESTLEN]; /* not converted bytes */
89     int		bw_restlen;	/* nr of bytes in bw_rest[] */
90     int		bw_first;	/* first write call */
91     char_u	*bw_conv_buf;	/* buffer for writing converted chars */
92     int		bw_conv_buflen; /* size of bw_conv_buf */
93     int		bw_conv_error;	/* set for conversion error */
94     linenr_T	bw_conv_error_lnum;  /* first line with error or zero */
95     linenr_T	bw_start_lnum;  /* line number at start of buffer */
96 #ifdef USE_ICONV
97     iconv_t	bw_iconv_fd;	/* descriptor for iconv() or -1 */
98 #endif
99 };
100 
101 static int  buf_write_bytes(struct bw_info *ip);
102 
103 static linenr_T readfile_linenr(linenr_T linecnt, char_u *p, char_u *endp);
104 static int ucs2bytes(unsigned c, char_u **pp, int flags);
105 static int need_conversion(char_u *fenc);
106 static int get_fio_flags(char_u *ptr);
107 static char_u *check_for_bom(char_u *p, long size, int *lenp, int flags);
108 static int make_bom(char_u *buf, char_u *name);
109 #ifdef MSWIN
110 static int get_win_fio_flags(char_u *ptr);
111 #endif
112 #ifdef MACOS_CONVERT
113 static int get_mac_fio_flags(char_u *ptr);
114 #endif
115 static char *e_auchangedbuf = N_("E812: Autocommands changed buffer or buffer name");
116 
117     void
118 filemess(
119     buf_T	*buf,
120     char_u	*name,
121     char_u	*s,
122     int		attr)
123 {
124     int		msg_scroll_save;
125 
126     if (msg_silent != 0)
127 	return;
128     msg_add_fname(buf, name);	    /* put file name in IObuff with quotes */
129     /* If it's extremely long, truncate it. */
130     if (STRLEN(IObuff) > IOSIZE - 80)
131 	IObuff[IOSIZE - 80] = NUL;
132     STRCAT(IObuff, s);
133     /*
134      * For the first message may have to start a new line.
135      * For further ones overwrite the previous one, reset msg_scroll before
136      * calling filemess().
137      */
138     msg_scroll_save = msg_scroll;
139     if (shortmess(SHM_OVERALL) && !exiting && p_verbose == 0)
140 	msg_scroll = FALSE;
141     if (!msg_scroll)	/* wait a bit when overwriting an error msg */
142 	check_for_delay(FALSE);
143     msg_start();
144     msg_scroll = msg_scroll_save;
145     msg_scrolled_ign = TRUE;
146     /* may truncate the message to avoid a hit-return prompt */
147     msg_outtrans_attr(msg_may_trunc(FALSE, IObuff), attr);
148     msg_clr_eos();
149     out_flush();
150     msg_scrolled_ign = FALSE;
151 }
152 
153 /*
154  * Read lines from file "fname" into the buffer after line "from".
155  *
156  * 1. We allocate blocks with lalloc, as big as possible.
157  * 2. Each block is filled with characters from the file with a single read().
158  * 3. The lines are inserted in the buffer with ml_append().
159  *
160  * (caller must check that fname != NULL, unless READ_STDIN is used)
161  *
162  * "lines_to_skip" is the number of lines that must be skipped
163  * "lines_to_read" is the number of lines that are appended
164  * When not recovering lines_to_skip is 0 and lines_to_read MAXLNUM.
165  *
166  * flags:
167  * READ_NEW	starting to edit a new buffer
168  * READ_FILTER	reading filter output
169  * READ_STDIN	read from stdin instead of a file
170  * READ_BUFFER	read from curbuf instead of a file (converting after reading
171  *		stdin)
172  * READ_DUMMY	read into a dummy buffer (to check if file contents changed)
173  * READ_KEEP_UNDO  don't clear undo info or read it from a file
174  * READ_FIFO	read from fifo/socket instead of a file
175  *
176  * return FAIL for failure, NOTDONE for directory (failure), or OK
177  */
178     int
179 readfile(
180     char_u	*fname,
181     char_u	*sfname,
182     linenr_T	from,
183     linenr_T	lines_to_skip,
184     linenr_T	lines_to_read,
185     exarg_T	*eap,			/* can be NULL! */
186     int		flags)
187 {
188     int		fd = 0;
189     int		newfile = (flags & READ_NEW);
190     int		check_readonly;
191     int		filtering = (flags & READ_FILTER);
192     int		read_stdin = (flags & READ_STDIN);
193     int		read_buffer = (flags & READ_BUFFER);
194     int		read_fifo = (flags & READ_FIFO);
195     int		set_options = newfile || read_buffer
196 					   || (eap != NULL && eap->read_edit);
197     linenr_T	read_buf_lnum = 1;	/* next line to read from curbuf */
198     colnr_T	read_buf_col = 0;	/* next char to read from this line */
199     char_u	c;
200     linenr_T	lnum = from;
201     char_u	*ptr = NULL;		/* pointer into read buffer */
202     char_u	*buffer = NULL;		/* read buffer */
203     char_u	*new_buffer = NULL;	/* init to shut up gcc */
204     char_u	*line_start = NULL;	/* init to shut up gcc */
205     int		wasempty;		/* buffer was empty before reading */
206     colnr_T	len;
207     long	size = 0;
208     char_u	*p;
209     off_T	filesize = 0;
210     int		skip_read = FALSE;
211 #ifdef FEAT_CRYPT
212     char_u	*cryptkey = NULL;
213     int		did_ask_for_key = FALSE;
214 #endif
215 #ifdef FEAT_PERSISTENT_UNDO
216     context_sha256_T sha_ctx;
217     int		read_undo_file = FALSE;
218 #endif
219     int		split = 0;		/* number of split lines */
220 #define UNKNOWN	 0x0fffffff		/* file size is unknown */
221     linenr_T	linecnt;
222     int		error = FALSE;		/* errors encountered */
223     int		ff_error = EOL_UNKNOWN; /* file format with errors */
224     long	linerest = 0;		/* remaining chars in line */
225 #ifdef UNIX
226     int		perm = 0;
227     int		swap_mode = -1;		/* protection bits for swap file */
228 #else
229     int		perm;
230 #endif
231     int		fileformat = 0;		/* end-of-line format */
232     int		keep_fileformat = FALSE;
233     stat_T	st;
234     int		file_readonly;
235     linenr_T	skip_count = 0;
236     linenr_T	read_count = 0;
237     int		msg_save = msg_scroll;
238     linenr_T	read_no_eol_lnum = 0;   /* non-zero lnum when last line of
239 					 * last read was missing the eol */
240     int		try_mac;
241     int		try_dos;
242     int		try_unix;
243     int		file_rewind = FALSE;
244     int		can_retry;
245     linenr_T	conv_error = 0;		/* line nr with conversion error */
246     linenr_T	illegal_byte = 0;	/* line nr with illegal byte */
247     int		keep_dest_enc = FALSE;	/* don't retry when char doesn't fit
248 					   in destination encoding */
249     int		bad_char_behavior = BAD_REPLACE;
250 					/* BAD_KEEP, BAD_DROP or character to
251 					 * replace with */
252     char_u	*tmpname = NULL;	/* name of 'charconvert' output file */
253     int		fio_flags = 0;
254     char_u	*fenc;			/* fileencoding to use */
255     int		fenc_alloced;		/* fenc_next is in allocated memory */
256     char_u	*fenc_next = NULL;	/* next item in 'fencs' or NULL */
257     int		advance_fenc = FALSE;
258     long	real_size = 0;
259 #ifdef USE_ICONV
260     iconv_t	iconv_fd = (iconv_t)-1;	/* descriptor for iconv() or -1 */
261 # ifdef FEAT_EVAL
262     int		did_iconv = FALSE;	/* TRUE when iconv() failed and trying
263 					   'charconvert' next */
264 # endif
265 #endif
266     int		converted = FALSE;	/* TRUE if conversion done */
267     int		notconverted = FALSE;	/* TRUE if conversion wanted but it
268 					   wasn't possible */
269     char_u	conv_rest[CONV_RESTLEN];
270     int		conv_restlen = 0;	/* nr of bytes in conv_rest[] */
271     buf_T	*old_curbuf;
272     char_u	*old_b_ffname;
273     char_u	*old_b_fname;
274     int		using_b_ffname;
275     int		using_b_fname;
276 
277     au_did_filetype = FALSE; /* reset before triggering any autocommands */
278 
279     curbuf->b_no_eol_lnum = 0;	/* in case it was set by the previous read */
280 
281     /*
282      * If there is no file name yet, use the one for the read file.
283      * BF_NOTEDITED is set to reflect this.
284      * Don't do this for a read from a filter.
285      * Only do this when 'cpoptions' contains the 'f' flag.
286      */
287     if (curbuf->b_ffname == NULL
288 	    && !filtering
289 	    && fname != NULL
290 	    && vim_strchr(p_cpo, CPO_FNAMER) != NULL
291 	    && !(flags & READ_DUMMY))
292     {
293 	if (set_rw_fname(fname, sfname) == FAIL)
294 	    return FAIL;
295     }
296 
297     /* Remember the initial values of curbuf, curbuf->b_ffname and
298      * curbuf->b_fname to detect whether they are altered as a result of
299      * executing nasty autocommands.  Also check if "fname" and "sfname"
300      * point to one of these values. */
301     old_curbuf = curbuf;
302     old_b_ffname = curbuf->b_ffname;
303     old_b_fname = curbuf->b_fname;
304     using_b_ffname = (fname == curbuf->b_ffname)
305 					      || (sfname == curbuf->b_ffname);
306     using_b_fname = (fname == curbuf->b_fname) || (sfname == curbuf->b_fname);
307 
308     /* After reading a file the cursor line changes but we don't want to
309      * display the line. */
310     ex_no_reprint = TRUE;
311 
312     /* don't display the file info for another buffer now */
313     need_fileinfo = FALSE;
314 
315     /*
316      * For Unix: Use the short file name whenever possible.
317      * Avoids problems with networks and when directory names are changed.
318      * Don't do this for MS-DOS, a "cd" in a sub-shell may have moved us to
319      * another directory, which we don't detect.
320      */
321     if (sfname == NULL)
322 	sfname = fname;
323 #if defined(UNIX)
324     fname = sfname;
325 #endif
326 
327     /*
328      * The BufReadCmd and FileReadCmd events intercept the reading process by
329      * executing the associated commands instead.
330      */
331     if (!filtering && !read_stdin && !read_buffer)
332     {
333 	pos_T	    pos;
334 
335 	pos = curbuf->b_op_start;
336 
337 	/* Set '[ mark to the line above where the lines go (line 1 if zero). */
338 	curbuf->b_op_start.lnum = ((from == 0) ? 1 : from);
339 	curbuf->b_op_start.col = 0;
340 
341 	if (newfile)
342 	{
343 	    if (apply_autocmds_exarg(EVENT_BUFREADCMD, NULL, sfname,
344 							  FALSE, curbuf, eap))
345 #ifdef FEAT_EVAL
346 		return aborting() ? FAIL : OK;
347 #else
348 		return OK;
349 #endif
350 	}
351 	else if (apply_autocmds_exarg(EVENT_FILEREADCMD, sfname, sfname,
352 							    FALSE, NULL, eap))
353 #ifdef FEAT_EVAL
354 	    return aborting() ? FAIL : OK;
355 #else
356 	    return OK;
357 #endif
358 
359 	curbuf->b_op_start = pos;
360     }
361 
362     if ((shortmess(SHM_OVER) || curbuf->b_help) && p_verbose == 0)
363 	msg_scroll = FALSE;	/* overwrite previous file message */
364     else
365 	msg_scroll = TRUE;	/* don't overwrite previous file message */
366 
367     /*
368      * If the name ends in a path separator, we can't open it.  Check here,
369      * because reading the file may actually work, but then creating the swap
370      * file may destroy it!  Reported on MS-DOS and Win 95.
371      * If the name is too long we might crash further on, quit here.
372      */
373     if (fname != NULL && *fname != NUL)
374     {
375 	p = fname + STRLEN(fname);
376 	if (after_pathsep(fname, p) || STRLEN(fname) >= MAXPATHL)
377 	{
378 	    filemess(curbuf, fname, (char_u *)_("Illegal file name"), 0);
379 	    msg_end();
380 	    msg_scroll = msg_save;
381 	    return FAIL;
382 	}
383     }
384 
385     if (!read_stdin && !read_buffer && !read_fifo)
386     {
387 #ifdef UNIX
388 	/*
389 	 * On Unix it is possible to read a directory, so we have to
390 	 * check for it before the mch_open().
391 	 */
392 	perm = mch_getperm(fname);
393 	if (perm >= 0 && !S_ISREG(perm)		    /* not a regular file ... */
394 		      && !S_ISFIFO(perm)	    /* ... or fifo */
395 		      && !S_ISSOCK(perm)	    /* ... or socket */
396 # ifdef OPEN_CHR_FILES
397 		      && !(S_ISCHR(perm) && is_dev_fd_file(fname))
398 			/* ... or a character special file named /dev/fd/<n> */
399 # endif
400 						)
401 	{
402 	    int retval = FAIL;
403 
404 	    if (S_ISDIR(perm))
405 	    {
406 		filemess(curbuf, fname, (char_u *)_("is a directory"), 0);
407 		retval = NOTDONE;
408 	    }
409 	    else
410 		filemess(curbuf, fname, (char_u *)_("is not a file"), 0);
411 	    msg_end();
412 	    msg_scroll = msg_save;
413 	    return retval;
414 	}
415 #endif
416 #if defined(MSWIN)
417 	/*
418 	 * MS-Windows allows opening a device, but we will probably get stuck
419 	 * trying to read it.
420 	 */
421 	if (!p_odev && mch_nodetype(fname) == NODE_WRITABLE)
422 	{
423 	    filemess(curbuf, fname, (char_u *)_("is a device (disabled with 'opendevice' option)"), 0);
424 	    msg_end();
425 	    msg_scroll = msg_save;
426 	    return FAIL;
427 	}
428 #endif
429     }
430 
431     /* Set default or forced 'fileformat' and 'binary'. */
432     set_file_options(set_options, eap);
433 
434     /*
435      * When opening a new file we take the readonly flag from the file.
436      * Default is r/w, can be set to r/o below.
437      * Don't reset it when in readonly mode
438      * Only set/reset b_p_ro when BF_CHECK_RO is set.
439      */
440     check_readonly = (newfile && (curbuf->b_flags & BF_CHECK_RO));
441     if (check_readonly && !readonlymode)
442 	curbuf->b_p_ro = FALSE;
443 
444     if (newfile && !read_stdin && !read_buffer && !read_fifo)
445     {
446 	/* Remember time of file. */
447 	if (mch_stat((char *)fname, &st) >= 0)
448 	{
449 	    buf_store_time(curbuf, &st, fname);
450 	    curbuf->b_mtime_read = curbuf->b_mtime;
451 #ifdef UNIX
452 	    /*
453 	     * Use the protection bits of the original file for the swap file.
454 	     * This makes it possible for others to read the name of the
455 	     * edited file from the swapfile, but only if they can read the
456 	     * edited file.
457 	     * Remove the "write" and "execute" bits for group and others
458 	     * (they must not write the swapfile).
459 	     * Add the "read" and "write" bits for the user, otherwise we may
460 	     * not be able to write to the file ourselves.
461 	     * Setting the bits is done below, after creating the swap file.
462 	     */
463 	    swap_mode = (st.st_mode & 0644) | 0600;
464 #endif
465 #ifdef FEAT_CW_EDITOR
466 	    /* Get the FSSpec on MacOS
467 	     * TODO: Update it properly when the buffer name changes
468 	     */
469 	    (void)GetFSSpecFromPath(curbuf->b_ffname, &curbuf->b_FSSpec);
470 #endif
471 #ifdef VMS
472 	    curbuf->b_fab_rfm = st.st_fab_rfm;
473 	    curbuf->b_fab_rat = st.st_fab_rat;
474 	    curbuf->b_fab_mrs = st.st_fab_mrs;
475 #endif
476 	}
477 	else
478 	{
479 	    curbuf->b_mtime = 0;
480 	    curbuf->b_mtime_read = 0;
481 	    curbuf->b_orig_size = 0;
482 	    curbuf->b_orig_mode = 0;
483 	}
484 
485 	/* Reset the "new file" flag.  It will be set again below when the
486 	 * file doesn't exist. */
487 	curbuf->b_flags &= ~(BF_NEW | BF_NEW_W);
488     }
489 
490 /*
491  * for UNIX: check readonly with perm and mch_access()
492  * for Amiga: check readonly by trying to open the file for writing
493  */
494     file_readonly = FALSE;
495     if (read_stdin)
496     {
497 #if defined(MSWIN)
498 	/* Force binary I/O on stdin to avoid CR-LF -> LF conversion. */
499 	setmode(0, O_BINARY);
500 #endif
501     }
502     else if (!read_buffer)
503     {
504 #ifdef USE_MCH_ACCESS
505 	if (
506 # ifdef UNIX
507 	    !(perm & 0222) ||
508 # endif
509 				mch_access((char *)fname, W_OK))
510 	    file_readonly = TRUE;
511 	fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);
512 #else
513 	if (!newfile
514 		|| readonlymode
515 		|| (fd = mch_open((char *)fname, O_RDWR | O_EXTRA, 0)) < 0)
516 	{
517 	    file_readonly = TRUE;
518 	    /* try to open ro */
519 	    fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);
520 	}
521 #endif
522     }
523 
524     if (fd < 0)			    /* cannot open at all */
525     {
526 #ifndef UNIX
527 	int	isdir_f;
528 #endif
529 	msg_scroll = msg_save;
530 #ifndef UNIX
531 	/*
532 	 * On Amiga we can't open a directory, check here.
533 	 */
534 	isdir_f = (mch_isdir(fname));
535 	perm = mch_getperm(fname);  /* check if the file exists */
536 	if (isdir_f)
537 	{
538 	    filemess(curbuf, sfname, (char_u *)_("is a directory"), 0);
539 	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
540 	}
541 	else
542 #endif
543 	    if (newfile)
544 	    {
545 		if (perm < 0
546 #ifdef ENOENT
547 			&& errno == ENOENT
548 #endif
549 		   )
550 		{
551 		    /*
552 		     * Set the 'new-file' flag, so that when the file has
553 		     * been created by someone else, a ":w" will complain.
554 		     */
555 		    curbuf->b_flags |= BF_NEW;
556 
557 		    /* Create a swap file now, so that other Vims are warned
558 		     * that we are editing this file.  Don't do this for a
559 		     * "nofile" or "nowrite" buffer type. */
560 #ifdef FEAT_QUICKFIX
561 		    if (!bt_dontwrite(curbuf))
562 #endif
563 		    {
564 			check_need_swap(newfile);
565 			/* SwapExists autocommand may mess things up */
566 			if (curbuf != old_curbuf
567 				|| (using_b_ffname
568 					&& (old_b_ffname != curbuf->b_ffname))
569 				|| (using_b_fname
570 					 && (old_b_fname != curbuf->b_fname)))
571 			{
572 			    emsg(_(e_auchangedbuf));
573 			    return FAIL;
574 			}
575 		    }
576 		    if (dir_of_file_exists(fname))
577 			filemess(curbuf, sfname, (char_u *)_("[New File]"), 0);
578 		    else
579 			filemess(curbuf, sfname,
580 					   (char_u *)_("[New DIRECTORY]"), 0);
581 #ifdef FEAT_VIMINFO
582 		    /* Even though this is a new file, it might have been
583 		     * edited before and deleted.  Get the old marks. */
584 		    check_marks_read();
585 #endif
586 		    /* Set forced 'fileencoding'.  */
587 		    if (eap != NULL)
588 			set_forced_fenc(eap);
589 		    apply_autocmds_exarg(EVENT_BUFNEWFILE, sfname, sfname,
590 							  FALSE, curbuf, eap);
591 		    /* remember the current fileformat */
592 		    save_file_ff(curbuf);
593 
594 #if defined(FEAT_EVAL)
595 		    if (aborting())   /* autocmds may abort script processing */
596 			return FAIL;
597 #endif
598 		    return OK;	    /* a new file is not an error */
599 		}
600 		else
601 		{
602 		    filemess(curbuf, sfname, (char_u *)(
603 # ifdef EFBIG
604 			    (errno == EFBIG) ? _("[File too big]") :
605 # endif
606 # ifdef EOVERFLOW
607 			    (errno == EOVERFLOW) ? _("[File too big]") :
608 # endif
609 						_("[Permission Denied]")), 0);
610 		    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
611 		}
612 	    }
613 
614 	return FAIL;
615     }
616 
617     /*
618      * Only set the 'ro' flag for readonly files the first time they are
619      * loaded.	Help files always get readonly mode
620      */
621     if ((check_readonly && file_readonly) || curbuf->b_help)
622 	curbuf->b_p_ro = TRUE;
623 
624     if (set_options)
625     {
626 	/* Don't change 'eol' if reading from buffer as it will already be
627 	 * correctly set when reading stdin. */
628 	if (!read_buffer)
629 	{
630 	    curbuf->b_p_eol = TRUE;
631 	    curbuf->b_start_eol = TRUE;
632 	}
633 	curbuf->b_p_bomb = FALSE;
634 	curbuf->b_start_bomb = FALSE;
635     }
636 
637     /* Create a swap file now, so that other Vims are warned that we are
638      * editing this file.
639      * Don't do this for a "nofile" or "nowrite" buffer type. */
640 #ifdef FEAT_QUICKFIX
641     if (!bt_dontwrite(curbuf))
642 #endif
643     {
644 	check_need_swap(newfile);
645 	if (!read_stdin && (curbuf != old_curbuf
646 		|| (using_b_ffname && (old_b_ffname != curbuf->b_ffname))
647 		|| (using_b_fname && (old_b_fname != curbuf->b_fname))))
648 	{
649 	    emsg(_(e_auchangedbuf));
650 	    if (!read_buffer)
651 		close(fd);
652 	    return FAIL;
653 	}
654 #ifdef UNIX
655 	/* Set swap file protection bits after creating it. */
656 	if (swap_mode > 0 && curbuf->b_ml.ml_mfp != NULL
657 			  && curbuf->b_ml.ml_mfp->mf_fname != NULL)
658 	{
659 	    char_u *swap_fname = curbuf->b_ml.ml_mfp->mf_fname;
660 
661 	    /*
662 	     * If the group-read bit is set but not the world-read bit, then
663 	     * the group must be equal to the group of the original file.  If
664 	     * we can't make that happen then reset the group-read bit.  This
665 	     * avoids making the swap file readable to more users when the
666 	     * primary group of the user is too permissive.
667 	     */
668 	    if ((swap_mode & 044) == 040)
669 	    {
670 		stat_T	swap_st;
671 
672 		if (mch_stat((char *)swap_fname, &swap_st) >= 0
673 			&& st.st_gid != swap_st.st_gid
674 # ifdef HAVE_FCHOWN
675 			&& fchown(curbuf->b_ml.ml_mfp->mf_fd, -1, st.st_gid)
676 									  == -1
677 # endif
678 		   )
679 		    swap_mode &= 0600;
680 	    }
681 
682 	    (void)mch_setperm(swap_fname, (long)swap_mode);
683 	}
684 #endif
685     }
686 
687 #if defined(HAS_SWAP_EXISTS_ACTION)
688     /* If "Quit" selected at ATTENTION dialog, don't load the file */
689     if (swap_exists_action == SEA_QUIT)
690     {
691 	if (!read_buffer && !read_stdin)
692 	    close(fd);
693 	return FAIL;
694     }
695 #endif
696 
697     ++no_wait_return;	    /* don't wait for return yet */
698 
699     /*
700      * Set '[ mark to the line above where the lines go (line 1 if zero).
701      */
702     curbuf->b_op_start.lnum = ((from == 0) ? 1 : from);
703     curbuf->b_op_start.col = 0;
704 
705     try_mac = (vim_strchr(p_ffs, 'm') != NULL);
706     try_dos = (vim_strchr(p_ffs, 'd') != NULL);
707     try_unix = (vim_strchr(p_ffs, 'x') != NULL);
708 
709     if (!read_buffer)
710     {
711 	int	m = msg_scroll;
712 	int	n = msg_scrolled;
713 
714 	/*
715 	 * The file must be closed again, the autocommands may want to change
716 	 * the file before reading it.
717 	 */
718 	if (!read_stdin)
719 	    close(fd);		/* ignore errors */
720 
721 	/*
722 	 * The output from the autocommands should not overwrite anything and
723 	 * should not be overwritten: Set msg_scroll, restore its value if no
724 	 * output was done.
725 	 */
726 	msg_scroll = TRUE;
727 	if (filtering)
728 	    apply_autocmds_exarg(EVENT_FILTERREADPRE, NULL, sfname,
729 							  FALSE, curbuf, eap);
730 	else if (read_stdin)
731 	    apply_autocmds_exarg(EVENT_STDINREADPRE, NULL, sfname,
732 							  FALSE, curbuf, eap);
733 	else if (newfile)
734 	    apply_autocmds_exarg(EVENT_BUFREADPRE, NULL, sfname,
735 							  FALSE, curbuf, eap);
736 	else
737 	    apply_autocmds_exarg(EVENT_FILEREADPRE, sfname, sfname,
738 							    FALSE, NULL, eap);
739 	/* autocommands may have changed it */
740 	try_mac = (vim_strchr(p_ffs, 'm') != NULL);
741 	try_dos = (vim_strchr(p_ffs, 'd') != NULL);
742 	try_unix = (vim_strchr(p_ffs, 'x') != NULL);
743 
744 	if (msg_scrolled == n)
745 	    msg_scroll = m;
746 
747 #ifdef FEAT_EVAL
748 	if (aborting())	    /* autocmds may abort script processing */
749 	{
750 	    --no_wait_return;
751 	    msg_scroll = msg_save;
752 	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
753 	    return FAIL;
754 	}
755 #endif
756 	/*
757 	 * Don't allow the autocommands to change the current buffer.
758 	 * Try to re-open the file.
759 	 *
760 	 * Don't allow the autocommands to change the buffer name either
761 	 * (cd for example) if it invalidates fname or sfname.
762 	 */
763 	if (!read_stdin && (curbuf != old_curbuf
764 		|| (using_b_ffname && (old_b_ffname != curbuf->b_ffname))
765 		|| (using_b_fname && (old_b_fname != curbuf->b_fname))
766 		|| (fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0)) < 0))
767 	{
768 	    --no_wait_return;
769 	    msg_scroll = msg_save;
770 	    if (fd < 0)
771 		emsg(_("E200: *ReadPre autocommands made the file unreadable"));
772 	    else
773 		emsg(_("E201: *ReadPre autocommands must not change current buffer"));
774 	    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
775 	    return FAIL;
776 	}
777     }
778 
779     /* Autocommands may add lines to the file, need to check if it is empty */
780     wasempty = (curbuf->b_ml.ml_flags & ML_EMPTY);
781 
782     if (!recoverymode && !filtering && !(flags & READ_DUMMY))
783     {
784 	/*
785 	 * Show the user that we are busy reading the input.  Sometimes this
786 	 * may take a while.  When reading from stdin another program may
787 	 * still be running, don't move the cursor to the last line, unless
788 	 * always using the GUI.
789 	 */
790 	if (read_stdin)
791 	{
792 	    if (!is_not_a_term())
793 	    {
794 #ifndef ALWAYS_USE_GUI
795 		mch_msg(_("Vim: Reading from stdin...\n"));
796 #endif
797 #ifdef FEAT_GUI
798 		/* Also write a message in the GUI window, if there is one. */
799 		if (gui.in_use && !gui.dying && !gui.starting)
800 		{
801 		    p = (char_u *)_("Reading from stdin...");
802 		    gui_write(p, (int)STRLEN(p));
803 		}
804 #endif
805 	    }
806 	}
807 	else if (!read_buffer)
808 	    filemess(curbuf, sfname, (char_u *)"", 0);
809     }
810 
811     msg_scroll = FALSE;			/* overwrite the file message */
812 
813     /*
814      * Set linecnt now, before the "retry" caused by a wrong guess for
815      * fileformat, and after the autocommands, which may change them.
816      */
817     linecnt = curbuf->b_ml.ml_line_count;
818 
819     /* "++bad=" argument. */
820     if (eap != NULL && eap->bad_char != 0)
821     {
822 	bad_char_behavior = eap->bad_char;
823 	if (set_options)
824 	    curbuf->b_bad_char = eap->bad_char;
825     }
826     else
827 	curbuf->b_bad_char = 0;
828 
829     /*
830      * Decide which 'encoding' to use or use first.
831      */
832     if (eap != NULL && eap->force_enc != 0)
833     {
834 	fenc = enc_canonize(eap->cmd + eap->force_enc);
835 	fenc_alloced = TRUE;
836 	keep_dest_enc = TRUE;
837     }
838     else if (curbuf->b_p_bin)
839     {
840 	fenc = (char_u *)"";		/* binary: don't convert */
841 	fenc_alloced = FALSE;
842     }
843     else if (curbuf->b_help)
844     {
845 	char_u	    firstline[80];
846 	int	    fc;
847 
848 	/* Help files are either utf-8 or latin1.  Try utf-8 first, if this
849 	 * fails it must be latin1.
850 	 * Always do this when 'encoding' is "utf-8".  Otherwise only do
851 	 * this when needed to avoid [converted] remarks all the time.
852 	 * It is needed when the first line contains non-ASCII characters.
853 	 * That is only in *.??x files. */
854 	fenc = (char_u *)"latin1";
855 	c = enc_utf8;
856 	if (!c && !read_stdin)
857 	{
858 	    fc = fname[STRLEN(fname) - 1];
859 	    if (TOLOWER_ASC(fc) == 'x')
860 	    {
861 		/* Read the first line (and a bit more).  Immediately rewind to
862 		 * the start of the file.  If the read() fails "len" is -1. */
863 		len = read_eintr(fd, firstline, 80);
864 		vim_lseek(fd, (off_T)0L, SEEK_SET);
865 		for (p = firstline; p < firstline + len; ++p)
866 		    if (*p >= 0x80)
867 		    {
868 			c = TRUE;
869 			break;
870 		    }
871 	    }
872 	}
873 
874 	if (c)
875 	{
876 	    fenc_next = fenc;
877 	    fenc = (char_u *)"utf-8";
878 
879 	    /* When the file is utf-8 but a character doesn't fit in
880 	     * 'encoding' don't retry.  In help text editing utf-8 bytes
881 	     * doesn't make sense. */
882 	    if (!enc_utf8)
883 		keep_dest_enc = TRUE;
884 	}
885 	fenc_alloced = FALSE;
886     }
887     else if (*p_fencs == NUL)
888     {
889 	fenc = curbuf->b_p_fenc;	/* use format from buffer */
890 	fenc_alloced = FALSE;
891     }
892     else
893     {
894 	fenc_next = p_fencs;		/* try items in 'fileencodings' */
895 	fenc = next_fenc(&fenc_next);
896 	fenc_alloced = TRUE;
897     }
898 
899     /*
900      * Jump back here to retry reading the file in different ways.
901      * Reasons to retry:
902      * - encoding conversion failed: try another one from "fenc_next"
903      * - BOM detected and fenc was set, need to setup conversion
904      * - "fileformat" check failed: try another
905      *
906      * Variables set for special retry actions:
907      * "file_rewind"	Rewind the file to start reading it again.
908      * "advance_fenc"	Advance "fenc" using "fenc_next".
909      * "skip_read"	Re-use already read bytes (BOM detected).
910      * "did_iconv"	iconv() conversion failed, try 'charconvert'.
911      * "keep_fileformat" Don't reset "fileformat".
912      *
913      * Other status indicators:
914      * "tmpname"	When != NULL did conversion with 'charconvert'.
915      *			Output file has to be deleted afterwards.
916      * "iconv_fd"	When != -1 did conversion with iconv().
917      */
918 retry:
919 
920     if (file_rewind)
921     {
922 	if (read_buffer)
923 	{
924 	    read_buf_lnum = 1;
925 	    read_buf_col = 0;
926 	}
927 	else if (read_stdin || vim_lseek(fd, (off_T)0L, SEEK_SET) != 0)
928 	{
929 	    /* Can't rewind the file, give up. */
930 	    error = TRUE;
931 	    goto failed;
932 	}
933 	/* Delete the previously read lines. */
934 	while (lnum > from)
935 	    ml_delete(lnum--, FALSE);
936 	file_rewind = FALSE;
937 	if (set_options)
938 	{
939 	    curbuf->b_p_bomb = FALSE;
940 	    curbuf->b_start_bomb = FALSE;
941 	}
942 	conv_error = 0;
943     }
944 
945     /*
946      * When retrying with another "fenc" and the first time "fileformat"
947      * will be reset.
948      */
949     if (keep_fileformat)
950 	keep_fileformat = FALSE;
951     else
952     {
953 	if (eap != NULL && eap->force_ff != 0)
954 	{
955 	    fileformat = get_fileformat_force(curbuf, eap);
956 	    try_unix = try_dos = try_mac = FALSE;
957 	}
958 	else if (curbuf->b_p_bin)
959 	    fileformat = EOL_UNIX;		/* binary: use Unix format */
960 	else if (*p_ffs == NUL)
961 	    fileformat = get_fileformat(curbuf);/* use format from buffer */
962 	else
963 	    fileformat = EOL_UNKNOWN;		/* detect from file */
964     }
965 
966 #ifdef USE_ICONV
967     if (iconv_fd != (iconv_t)-1)
968     {
969 	/* aborted conversion with iconv(), close the descriptor */
970 	iconv_close(iconv_fd);
971 	iconv_fd = (iconv_t)-1;
972     }
973 #endif
974 
975     if (advance_fenc)
976     {
977 	/*
978 	 * Try the next entry in 'fileencodings'.
979 	 */
980 	advance_fenc = FALSE;
981 
982 	if (eap != NULL && eap->force_enc != 0)
983 	{
984 	    /* Conversion given with "++cc=" wasn't possible, read
985 	     * without conversion. */
986 	    notconverted = TRUE;
987 	    conv_error = 0;
988 	    if (fenc_alloced)
989 		vim_free(fenc);
990 	    fenc = (char_u *)"";
991 	    fenc_alloced = FALSE;
992 	}
993 	else
994 	{
995 	    if (fenc_alloced)
996 		vim_free(fenc);
997 	    if (fenc_next != NULL)
998 	    {
999 		fenc = next_fenc(&fenc_next);
1000 		fenc_alloced = (fenc_next != NULL);
1001 	    }
1002 	    else
1003 	    {
1004 		fenc = (char_u *)"";
1005 		fenc_alloced = FALSE;
1006 	    }
1007 	}
1008 	if (tmpname != NULL)
1009 	{
1010 	    mch_remove(tmpname);		/* delete converted file */
1011 	    VIM_CLEAR(tmpname);
1012 	}
1013     }
1014 
1015     /*
1016      * Conversion may be required when the encoding of the file is different
1017      * from 'encoding' or 'encoding' is UTF-16, UCS-2 or UCS-4.
1018      */
1019     fio_flags = 0;
1020     converted = need_conversion(fenc);
1021     if (converted)
1022     {
1023 
1024 	/* "ucs-bom" means we need to check the first bytes of the file
1025 	 * for a BOM. */
1026 	if (STRCMP(fenc, ENC_UCSBOM) == 0)
1027 	    fio_flags = FIO_UCSBOM;
1028 
1029 	/*
1030 	 * Check if UCS-2/4 or Latin1 to UTF-8 conversion needs to be
1031 	 * done.  This is handled below after read().  Prepare the
1032 	 * fio_flags to avoid having to parse the string each time.
1033 	 * Also check for Unicode to Latin1 conversion, because iconv()
1034 	 * appears not to handle this correctly.  This works just like
1035 	 * conversion to UTF-8 except how the resulting character is put in
1036 	 * the buffer.
1037 	 */
1038 	else if (enc_utf8 || STRCMP(p_enc, "latin1") == 0)
1039 	    fio_flags = get_fio_flags(fenc);
1040 
1041 #ifdef MSWIN
1042 	/*
1043 	 * Conversion from an MS-Windows codepage to UTF-8 or another codepage
1044 	 * is handled with MultiByteToWideChar().
1045 	 */
1046 	if (fio_flags == 0)
1047 	    fio_flags = get_win_fio_flags(fenc);
1048 #endif
1049 
1050 #ifdef MACOS_CONVERT
1051 	/* Conversion from Apple MacRoman to latin1 or UTF-8 */
1052 	if (fio_flags == 0)
1053 	    fio_flags = get_mac_fio_flags(fenc);
1054 #endif
1055 
1056 #ifdef USE_ICONV
1057 	/*
1058 	 * Try using iconv() if we can't convert internally.
1059 	 */
1060 	if (fio_flags == 0
1061 # ifdef FEAT_EVAL
1062 		&& !did_iconv
1063 # endif
1064 		)
1065 	    iconv_fd = (iconv_t)my_iconv_open(
1066 				  enc_utf8 ? (char_u *)"utf-8" : p_enc, fenc);
1067 #endif
1068 
1069 #ifdef FEAT_EVAL
1070 	/*
1071 	 * Use the 'charconvert' expression when conversion is required
1072 	 * and we can't do it internally or with iconv().
1073 	 */
1074 	if (fio_flags == 0 && !read_stdin && !read_buffer && *p_ccv != NUL
1075 						    && !read_fifo
1076 # ifdef USE_ICONV
1077 						    && iconv_fd == (iconv_t)-1
1078 # endif
1079 		)
1080 	{
1081 # ifdef USE_ICONV
1082 	    did_iconv = FALSE;
1083 # endif
1084 	    /* Skip conversion when it's already done (retry for wrong
1085 	     * "fileformat"). */
1086 	    if (tmpname == NULL)
1087 	    {
1088 		tmpname = readfile_charconvert(fname, fenc, &fd);
1089 		if (tmpname == NULL)
1090 		{
1091 		    /* Conversion failed.  Try another one. */
1092 		    advance_fenc = TRUE;
1093 		    if (fd < 0)
1094 		    {
1095 			/* Re-opening the original file failed! */
1096 			emsg(_("E202: Conversion made file unreadable!"));
1097 			error = TRUE;
1098 			goto failed;
1099 		    }
1100 		    goto retry;
1101 		}
1102 	    }
1103 	}
1104 	else
1105 #endif
1106 	{
1107 	    if (fio_flags == 0
1108 #ifdef USE_ICONV
1109 		    && iconv_fd == (iconv_t)-1
1110 #endif
1111 	       )
1112 	    {
1113 		/* Conversion wanted but we can't.
1114 		 * Try the next conversion in 'fileencodings' */
1115 		advance_fenc = TRUE;
1116 		goto retry;
1117 	    }
1118 	}
1119     }
1120 
1121     /* Set "can_retry" when it's possible to rewind the file and try with
1122      * another "fenc" value.  It's FALSE when no other "fenc" to try, reading
1123      * stdin or fixed at a specific encoding. */
1124     can_retry = (*fenc != NUL && !read_stdin && !read_fifo && !keep_dest_enc);
1125 
1126     if (!skip_read)
1127     {
1128 	linerest = 0;
1129 	filesize = 0;
1130 	skip_count = lines_to_skip;
1131 	read_count = lines_to_read;
1132 	conv_restlen = 0;
1133 #ifdef FEAT_PERSISTENT_UNDO
1134 	read_undo_file = (newfile && (flags & READ_KEEP_UNDO) == 0
1135 				  && curbuf->b_ffname != NULL
1136 				  && curbuf->b_p_udf
1137 				  && !filtering
1138 				  && !read_fifo
1139 				  && !read_stdin
1140 				  && !read_buffer);
1141 	if (read_undo_file)
1142 	    sha256_start(&sha_ctx);
1143 #endif
1144 #ifdef FEAT_CRYPT
1145 	if (curbuf->b_cryptstate != NULL)
1146 	{
1147 	    /* Need to free the state, but keep the key, don't want to ask for
1148 	     * it again. */
1149 	    crypt_free_state(curbuf->b_cryptstate);
1150 	    curbuf->b_cryptstate = NULL;
1151 	}
1152 #endif
1153     }
1154 
1155     while (!error && !got_int)
1156     {
1157 	/*
1158 	 * We allocate as much space for the file as we can get, plus
1159 	 * space for the old line plus room for one terminating NUL.
1160 	 * The amount is limited by the fact that read() only can read
1161 	 * upto max_unsigned characters (and other things).
1162 	 */
1163 	if (!skip_read)
1164 	{
1165 #if defined(SSIZE_MAX) && (SSIZE_MAX < 0x10000L)
1166 		size = SSIZE_MAX;		    /* use max I/O size, 52K */
1167 #else
1168 		/* Use buffer >= 64K.  Add linerest to double the size if the
1169 		 * line gets very long, to avoid a lot of copying. But don't
1170 		 * read more than 1 Mbyte at a time, so we can be interrupted.
1171 		 */
1172 		size = 0x10000L + linerest;
1173 		if (size > 0x100000L)
1174 		    size = 0x100000L;
1175 #endif
1176 	}
1177 
1178 	/* Protect against the argument of lalloc() going negative. */
1179 	if (size < 0 || size + linerest + 1 < 0 || linerest >= MAXCOL)
1180 	{
1181 	    ++split;
1182 	    *ptr = NL;		    /* split line by inserting a NL */
1183 	    size = 1;
1184 	}
1185 	else
1186 	{
1187 	    if (!skip_read)
1188 	    {
1189 		for ( ; size >= 10; size = (long)((long_u)size >> 1))
1190 		{
1191 		    if ((new_buffer = lalloc((long_u)(size + linerest + 1),
1192 							      FALSE)) != NULL)
1193 			break;
1194 		}
1195 		if (new_buffer == NULL)
1196 		{
1197 		    do_outofmem_msg((long_u)(size * 2 + linerest + 1));
1198 		    error = TRUE;
1199 		    break;
1200 		}
1201 		if (linerest)	/* copy characters from the previous buffer */
1202 		    mch_memmove(new_buffer, ptr - linerest, (size_t)linerest);
1203 		vim_free(buffer);
1204 		buffer = new_buffer;
1205 		ptr = buffer + linerest;
1206 		line_start = buffer;
1207 
1208 		/* May need room to translate into.
1209 		 * For iconv() we don't really know the required space, use a
1210 		 * factor ICONV_MULT.
1211 		 * latin1 to utf-8: 1 byte becomes up to 2 bytes
1212 		 * utf-16 to utf-8: 2 bytes become up to 3 bytes, 4 bytes
1213 		 * become up to 4 bytes, size must be multiple of 2
1214 		 * ucs-2 to utf-8: 2 bytes become up to 3 bytes, size must be
1215 		 * multiple of 2
1216 		 * ucs-4 to utf-8: 4 bytes become up to 6 bytes, size must be
1217 		 * multiple of 4 */
1218 		real_size = (int)size;
1219 #ifdef USE_ICONV
1220 		if (iconv_fd != (iconv_t)-1)
1221 		    size = size / ICONV_MULT;
1222 		else
1223 #endif
1224 		    if (fio_flags & FIO_LATIN1)
1225 		    size = size / 2;
1226 		else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
1227 		    size = (size * 2 / 3) & ~1;
1228 		else if (fio_flags & FIO_UCS4)
1229 		    size = (size * 2 / 3) & ~3;
1230 		else if (fio_flags == FIO_UCSBOM)
1231 		    size = size / ICONV_MULT;	/* worst case */
1232 #ifdef MSWIN
1233 		else if (fio_flags & FIO_CODEPAGE)
1234 		    size = size / ICONV_MULT;	/* also worst case */
1235 #endif
1236 #ifdef MACOS_CONVERT
1237 		else if (fio_flags & FIO_MACROMAN)
1238 		    size = size / ICONV_MULT;	/* also worst case */
1239 #endif
1240 
1241 		if (conv_restlen > 0)
1242 		{
1243 		    /* Insert unconverted bytes from previous line. */
1244 		    mch_memmove(ptr, conv_rest, conv_restlen);
1245 		    ptr += conv_restlen;
1246 		    size -= conv_restlen;
1247 		}
1248 
1249 		if (read_buffer)
1250 		{
1251 		    /*
1252 		     * Read bytes from curbuf.  Used for converting text read
1253 		     * from stdin.
1254 		     */
1255 		    if (read_buf_lnum > from)
1256 			size = 0;
1257 		    else
1258 		    {
1259 			int	n, ni;
1260 			long	tlen;
1261 
1262 			tlen = 0;
1263 			for (;;)
1264 			{
1265 			    p = ml_get(read_buf_lnum) + read_buf_col;
1266 			    n = (int)STRLEN(p);
1267 			    if ((int)tlen + n + 1 > size)
1268 			    {
1269 				/* Filled up to "size", append partial line.
1270 				 * Change NL to NUL to reverse the effect done
1271 				 * below. */
1272 				n = (int)(size - tlen);
1273 				for (ni = 0; ni < n; ++ni)
1274 				{
1275 				    if (p[ni] == NL)
1276 					ptr[tlen++] = NUL;
1277 				    else
1278 					ptr[tlen++] = p[ni];
1279 				}
1280 				read_buf_col += n;
1281 				break;
1282 			    }
1283 			    else
1284 			    {
1285 				/* Append whole line and new-line.  Change NL
1286 				 * to NUL to reverse the effect done below. */
1287 				for (ni = 0; ni < n; ++ni)
1288 				{
1289 				    if (p[ni] == NL)
1290 					ptr[tlen++] = NUL;
1291 				    else
1292 					ptr[tlen++] = p[ni];
1293 				}
1294 				ptr[tlen++] = NL;
1295 				read_buf_col = 0;
1296 				if (++read_buf_lnum > from)
1297 				{
1298 				    /* When the last line didn't have an
1299 				     * end-of-line don't add it now either. */
1300 				    if (!curbuf->b_p_eol)
1301 					--tlen;
1302 				    size = tlen;
1303 				    break;
1304 				}
1305 			    }
1306 			}
1307 		    }
1308 		}
1309 		else
1310 		{
1311 		    /*
1312 		     * Read bytes from the file.
1313 		     */
1314 		    size = read_eintr(fd, ptr, size);
1315 		}
1316 
1317 #ifdef FEAT_CRYPT
1318 		/*
1319 		 * At start of file: Check for magic number of encryption.
1320 		 */
1321 		if (filesize == 0 && size > 0)
1322 		    cryptkey = check_for_cryptkey(cryptkey, ptr, &size,
1323 						  &filesize, newfile, sfname,
1324 						  &did_ask_for_key);
1325 		/*
1326 		 * Decrypt the read bytes.  This is done before checking for
1327 		 * EOF because the crypt layer may be buffering.
1328 		 */
1329 		if (cryptkey != NULL && curbuf->b_cryptstate != NULL
1330 								   && size > 0)
1331 		{
1332 # ifdef CRYPT_NOT_INPLACE
1333 		    if (crypt_works_inplace(curbuf->b_cryptstate))
1334 		    {
1335 # endif
1336 			crypt_decode_inplace(curbuf->b_cryptstate, ptr, size);
1337 # ifdef CRYPT_NOT_INPLACE
1338 		    }
1339 		    else
1340 		    {
1341 			char_u	*newptr = NULL;
1342 			int	decrypted_size;
1343 
1344 			decrypted_size = crypt_decode_alloc(
1345 				    curbuf->b_cryptstate, ptr, size, &newptr);
1346 
1347 			/* If the crypt layer is buffering, not producing
1348 			 * anything yet, need to read more. */
1349 			if (decrypted_size == 0)
1350 			    continue;
1351 
1352 			if (linerest == 0)
1353 			{
1354 			    /* Simple case: reuse returned buffer (may be
1355 			     * NULL, checked later). */
1356 			    new_buffer = newptr;
1357 			}
1358 			else
1359 			{
1360 			    long_u	new_size;
1361 
1362 			    /* Need new buffer to add bytes carried over. */
1363 			    new_size = (long_u)(decrypted_size + linerest + 1);
1364 			    new_buffer = lalloc(new_size, FALSE);
1365 			    if (new_buffer == NULL)
1366 			    {
1367 				do_outofmem_msg(new_size);
1368 				error = TRUE;
1369 				break;
1370 			    }
1371 
1372 			    mch_memmove(new_buffer, buffer, linerest);
1373 			    if (newptr != NULL)
1374 				mch_memmove(new_buffer + linerest, newptr,
1375 							      decrypted_size);
1376 			}
1377 
1378 			if (new_buffer != NULL)
1379 			{
1380 			    vim_free(buffer);
1381 			    buffer = new_buffer;
1382 			    new_buffer = NULL;
1383 			    line_start = buffer;
1384 			    ptr = buffer + linerest;
1385 			}
1386 			size = decrypted_size;
1387 		    }
1388 # endif
1389 		}
1390 #endif
1391 
1392 		if (size <= 0)
1393 		{
1394 		    if (size < 0)		    /* read error */
1395 			error = TRUE;
1396 		    else if (conv_restlen > 0)
1397 		    {
1398 			/*
1399 			 * Reached end-of-file but some trailing bytes could
1400 			 * not be converted.  Truncated file?
1401 			 */
1402 
1403 			/* When we did a conversion report an error. */
1404 			if (fio_flags != 0
1405 #ifdef USE_ICONV
1406 				|| iconv_fd != (iconv_t)-1
1407 #endif
1408 			   )
1409 			{
1410 			    if (can_retry)
1411 				goto rewind_retry;
1412 			    if (conv_error == 0)
1413 				conv_error = curbuf->b_ml.ml_line_count
1414 								- linecnt + 1;
1415 			}
1416 			/* Remember the first linenr with an illegal byte */
1417 			else if (illegal_byte == 0)
1418 			    illegal_byte = curbuf->b_ml.ml_line_count
1419 								- linecnt + 1;
1420 			if (bad_char_behavior == BAD_DROP)
1421 			{
1422 			    *(ptr - conv_restlen) = NUL;
1423 			    conv_restlen = 0;
1424 			}
1425 			else
1426 			{
1427 			    /* Replace the trailing bytes with the replacement
1428 			     * character if we were converting; if we weren't,
1429 			     * leave the UTF8 checking code to do it, as it
1430 			     * works slightly differently. */
1431 			    if (bad_char_behavior != BAD_KEEP && (fio_flags != 0
1432 #ifdef USE_ICONV
1433 				    || iconv_fd != (iconv_t)-1
1434 #endif
1435 			       ))
1436 			    {
1437 				while (conv_restlen > 0)
1438 				{
1439 				    *(--ptr) = bad_char_behavior;
1440 				    --conv_restlen;
1441 				}
1442 			    }
1443 			    fio_flags = 0;	/* don't convert this */
1444 #ifdef USE_ICONV
1445 			    if (iconv_fd != (iconv_t)-1)
1446 			    {
1447 				iconv_close(iconv_fd);
1448 				iconv_fd = (iconv_t)-1;
1449 			    }
1450 #endif
1451 			}
1452 		    }
1453 		}
1454 	    }
1455 	    skip_read = FALSE;
1456 
1457 	    /*
1458 	     * At start of file (or after crypt magic number): Check for BOM.
1459 	     * Also check for a BOM for other Unicode encodings, but not after
1460 	     * converting with 'charconvert' or when a BOM has already been
1461 	     * found.
1462 	     */
1463 	    if ((filesize == 0
1464 #ifdef FEAT_CRYPT
1465 		   || (cryptkey != NULL
1466 			&& filesize == crypt_get_header_len(
1467 						 crypt_get_method_nr(curbuf)))
1468 #endif
1469 		       )
1470 		    && (fio_flags == FIO_UCSBOM
1471 			|| (!curbuf->b_p_bomb
1472 			    && tmpname == NULL
1473 			    && (*fenc == 'u' || (*fenc == NUL && enc_utf8)))))
1474 	    {
1475 		char_u	*ccname;
1476 		int	blen;
1477 
1478 		/* no BOM detection in a short file or in binary mode */
1479 		if (size < 2 || curbuf->b_p_bin)
1480 		    ccname = NULL;
1481 		else
1482 		    ccname = check_for_bom(ptr, size, &blen,
1483 		      fio_flags == FIO_UCSBOM ? FIO_ALL : get_fio_flags(fenc));
1484 		if (ccname != NULL)
1485 		{
1486 		    /* Remove BOM from the text */
1487 		    filesize += blen;
1488 		    size -= blen;
1489 		    mch_memmove(ptr, ptr + blen, (size_t)size);
1490 		    if (set_options)
1491 		    {
1492 			curbuf->b_p_bomb = TRUE;
1493 			curbuf->b_start_bomb = TRUE;
1494 		    }
1495 		}
1496 
1497 		if (fio_flags == FIO_UCSBOM)
1498 		{
1499 		    if (ccname == NULL)
1500 		    {
1501 			/* No BOM detected: retry with next encoding. */
1502 			advance_fenc = TRUE;
1503 		    }
1504 		    else
1505 		    {
1506 			/* BOM detected: set "fenc" and jump back */
1507 			if (fenc_alloced)
1508 			    vim_free(fenc);
1509 			fenc = ccname;
1510 			fenc_alloced = FALSE;
1511 		    }
1512 		    /* retry reading without getting new bytes or rewinding */
1513 		    skip_read = TRUE;
1514 		    goto retry;
1515 		}
1516 	    }
1517 
1518 	    /* Include not converted bytes. */
1519 	    ptr -= conv_restlen;
1520 	    size += conv_restlen;
1521 	    conv_restlen = 0;
1522 	    /*
1523 	     * Break here for a read error or end-of-file.
1524 	     */
1525 	    if (size <= 0)
1526 		break;
1527 
1528 
1529 #ifdef USE_ICONV
1530 	    if (iconv_fd != (iconv_t)-1)
1531 	    {
1532 		/*
1533 		 * Attempt conversion of the read bytes to 'encoding' using
1534 		 * iconv().
1535 		 */
1536 		const char	*fromp;
1537 		char		*top;
1538 		size_t		from_size;
1539 		size_t		to_size;
1540 
1541 		fromp = (char *)ptr;
1542 		from_size = size;
1543 		ptr += size;
1544 		top = (char *)ptr;
1545 		to_size = real_size - size;
1546 
1547 		/*
1548 		 * If there is conversion error or not enough room try using
1549 		 * another conversion.  Except for when there is no
1550 		 * alternative (help files).
1551 		 */
1552 		while ((iconv(iconv_fd, (void *)&fromp, &from_size,
1553 							       &top, &to_size)
1554 			    == (size_t)-1 && ICONV_ERRNO != ICONV_EINVAL)
1555 						  || from_size > CONV_RESTLEN)
1556 		{
1557 		    if (can_retry)
1558 			goto rewind_retry;
1559 		    if (conv_error == 0)
1560 			conv_error = readfile_linenr(linecnt,
1561 							  ptr, (char_u *)top);
1562 
1563 		    /* Deal with a bad byte and continue with the next. */
1564 		    ++fromp;
1565 		    --from_size;
1566 		    if (bad_char_behavior == BAD_KEEP)
1567 		    {
1568 			*top++ = *(fromp - 1);
1569 			--to_size;
1570 		    }
1571 		    else if (bad_char_behavior != BAD_DROP)
1572 		    {
1573 			*top++ = bad_char_behavior;
1574 			--to_size;
1575 		    }
1576 		}
1577 
1578 		if (from_size > 0)
1579 		{
1580 		    /* Some remaining characters, keep them for the next
1581 		     * round. */
1582 		    mch_memmove(conv_rest, (char_u *)fromp, from_size);
1583 		    conv_restlen = (int)from_size;
1584 		}
1585 
1586 		/* move the linerest to before the converted characters */
1587 		line_start = ptr - linerest;
1588 		mch_memmove(line_start, buffer, (size_t)linerest);
1589 		size = (long)((char_u *)top - ptr);
1590 	    }
1591 #endif
1592 
1593 #ifdef MSWIN
1594 	    if (fio_flags & FIO_CODEPAGE)
1595 	    {
1596 		char_u	*src, *dst;
1597 		WCHAR	ucs2buf[3];
1598 		int	ucs2len;
1599 		int	codepage = FIO_GET_CP(fio_flags);
1600 		int	bytelen;
1601 		int	found_bad;
1602 		char	replstr[2];
1603 
1604 		/*
1605 		 * Conversion from an MS-Windows codepage or UTF-8 to UTF-8 or
1606 		 * a codepage, using standard MS-Windows functions.  This
1607 		 * requires two steps:
1608 		 * 1. convert from 'fileencoding' to ucs-2
1609 		 * 2. convert from ucs-2 to 'encoding'
1610 		 *
1611 		 * Because there may be illegal bytes AND an incomplete byte
1612 		 * sequence at the end, we may have to do the conversion one
1613 		 * character at a time to get it right.
1614 		 */
1615 
1616 		/* Replacement string for WideCharToMultiByte(). */
1617 		if (bad_char_behavior > 0)
1618 		    replstr[0] = bad_char_behavior;
1619 		else
1620 		    replstr[0] = '?';
1621 		replstr[1] = NUL;
1622 
1623 		/*
1624 		 * Move the bytes to the end of the buffer, so that we have
1625 		 * room to put the result at the start.
1626 		 */
1627 		src = ptr + real_size - size;
1628 		mch_memmove(src, ptr, size);
1629 
1630 		/*
1631 		 * Do the conversion.
1632 		 */
1633 		dst = ptr;
1634 		size = size;
1635 		while (size > 0)
1636 		{
1637 		    found_bad = FALSE;
1638 
1639 #  ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
1640 		    if (codepage == CP_UTF8)
1641 		    {
1642 			/* Handle CP_UTF8 input ourselves to be able to handle
1643 			 * trailing bytes properly.
1644 			 * Get one UTF-8 character from src. */
1645 			bytelen = (int)utf_ptr2len_len(src, size);
1646 			if (bytelen > size)
1647 			{
1648 			    /* Only got some bytes of a character.  Normally
1649 			     * it's put in "conv_rest", but if it's too long
1650 			     * deal with it as if they were illegal bytes. */
1651 			    if (bytelen <= CONV_RESTLEN)
1652 				break;
1653 
1654 			    /* weird overlong byte sequence */
1655 			    bytelen = size;
1656 			    found_bad = TRUE;
1657 			}
1658 			else
1659 			{
1660 			    int	    u8c = utf_ptr2char(src);
1661 
1662 			    if (u8c > 0xffff || (*src >= 0x80 && bytelen == 1))
1663 				found_bad = TRUE;
1664 			    ucs2buf[0] = u8c;
1665 			    ucs2len = 1;
1666 			}
1667 		    }
1668 		    else
1669 #  endif
1670 		    {
1671 			/* We don't know how long the byte sequence is, try
1672 			 * from one to three bytes. */
1673 			for (bytelen = 1; bytelen <= size && bytelen <= 3;
1674 								    ++bytelen)
1675 			{
1676 			    ucs2len = MultiByteToWideChar(codepage,
1677 							 MB_ERR_INVALID_CHARS,
1678 							 (LPCSTR)src, bytelen,
1679 								   ucs2buf, 3);
1680 			    if (ucs2len > 0)
1681 				break;
1682 			}
1683 			if (ucs2len == 0)
1684 			{
1685 			    /* If we have only one byte then it's probably an
1686 			     * incomplete byte sequence.  Otherwise discard
1687 			     * one byte as a bad character. */
1688 			    if (size == 1)
1689 				break;
1690 			    found_bad = TRUE;
1691 			    bytelen = 1;
1692 			}
1693 		    }
1694 
1695 		    if (!found_bad)
1696 		    {
1697 			int	i;
1698 
1699 			/* Convert "ucs2buf[ucs2len]" to 'enc' in "dst". */
1700 			if (enc_utf8)
1701 			{
1702 			    /* From UCS-2 to UTF-8.  Cannot fail. */
1703 			    for (i = 0; i < ucs2len; ++i)
1704 				dst += utf_char2bytes(ucs2buf[i], dst);
1705 			}
1706 			else
1707 			{
1708 			    BOOL	bad = FALSE;
1709 			    int		dstlen;
1710 
1711 			    /* From UCS-2 to "enc_codepage".  If the
1712 			     * conversion uses the default character "?",
1713 			     * the data doesn't fit in this encoding. */
1714 			    dstlen = WideCharToMultiByte(enc_codepage, 0,
1715 				    (LPCWSTR)ucs2buf, ucs2len,
1716 				    (LPSTR)dst, (int)(src - dst),
1717 				    replstr, &bad);
1718 			    if (bad)
1719 				found_bad = TRUE;
1720 			    else
1721 				dst += dstlen;
1722 			}
1723 		    }
1724 
1725 		    if (found_bad)
1726 		    {
1727 			/* Deal with bytes we can't convert. */
1728 			if (can_retry)
1729 			    goto rewind_retry;
1730 			if (conv_error == 0)
1731 			    conv_error = readfile_linenr(linecnt, ptr, dst);
1732 			if (bad_char_behavior != BAD_DROP)
1733 			{
1734 			    if (bad_char_behavior == BAD_KEEP)
1735 			    {
1736 				mch_memmove(dst, src, bytelen);
1737 				dst += bytelen;
1738 			    }
1739 			    else
1740 				*dst++ = bad_char_behavior;
1741 			}
1742 		    }
1743 
1744 		    src += bytelen;
1745 		    size -= bytelen;
1746 		}
1747 
1748 		if (size > 0)
1749 		{
1750 		    /* An incomplete byte sequence remaining. */
1751 		    mch_memmove(conv_rest, src, size);
1752 		    conv_restlen = size;
1753 		}
1754 
1755 		/* The new size is equal to how much "dst" was advanced. */
1756 		size = (long)(dst - ptr);
1757 	    }
1758 	    else
1759 #endif
1760 #ifdef MACOS_CONVERT
1761 	    if (fio_flags & FIO_MACROMAN)
1762 	    {
1763 		/*
1764 		 * Conversion from Apple MacRoman char encoding to UTF-8 or
1765 		 * latin1.  This is in os_mac_conv.c.
1766 		 */
1767 		if (macroman2enc(ptr, &size, real_size) == FAIL)
1768 		    goto rewind_retry;
1769 	    }
1770 	    else
1771 #endif
1772 	    if (fio_flags != 0)
1773 	    {
1774 		int	u8c;
1775 		char_u	*dest;
1776 		char_u	*tail = NULL;
1777 
1778 		/*
1779 		 * "enc_utf8" set: Convert Unicode or Latin1 to UTF-8.
1780 		 * "enc_utf8" not set: Convert Unicode to Latin1.
1781 		 * Go from end to start through the buffer, because the number
1782 		 * of bytes may increase.
1783 		 * "dest" points to after where the UTF-8 bytes go, "p" points
1784 		 * to after the next character to convert.
1785 		 */
1786 		dest = ptr + real_size;
1787 		if (fio_flags == FIO_LATIN1 || fio_flags == FIO_UTF8)
1788 		{
1789 		    p = ptr + size;
1790 		    if (fio_flags == FIO_UTF8)
1791 		    {
1792 			/* Check for a trailing incomplete UTF-8 sequence */
1793 			tail = ptr + size - 1;
1794 			while (tail > ptr && (*tail & 0xc0) == 0x80)
1795 			    --tail;
1796 			if (tail + utf_byte2len(*tail) <= ptr + size)
1797 			    tail = NULL;
1798 			else
1799 			    p = tail;
1800 		    }
1801 		}
1802 		else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
1803 		{
1804 		    /* Check for a trailing byte */
1805 		    p = ptr + (size & ~1);
1806 		    if (size & 1)
1807 			tail = p;
1808 		    if ((fio_flags & FIO_UTF16) && p > ptr)
1809 		    {
1810 			/* Check for a trailing leading word */
1811 			if (fio_flags & FIO_ENDIAN_L)
1812 			{
1813 			    u8c = (*--p << 8);
1814 			    u8c += *--p;
1815 			}
1816 			else
1817 			{
1818 			    u8c = *--p;
1819 			    u8c += (*--p << 8);
1820 			}
1821 			if (u8c >= 0xd800 && u8c <= 0xdbff)
1822 			    tail = p;
1823 			else
1824 			    p += 2;
1825 		    }
1826 		}
1827 		else /*  FIO_UCS4 */
1828 		{
1829 		    /* Check for trailing 1, 2 or 3 bytes */
1830 		    p = ptr + (size & ~3);
1831 		    if (size & 3)
1832 			tail = p;
1833 		}
1834 
1835 		/* If there is a trailing incomplete sequence move it to
1836 		 * conv_rest[]. */
1837 		if (tail != NULL)
1838 		{
1839 		    conv_restlen = (int)((ptr + size) - tail);
1840 		    mch_memmove(conv_rest, (char_u *)tail, conv_restlen);
1841 		    size -= conv_restlen;
1842 		}
1843 
1844 
1845 		while (p > ptr)
1846 		{
1847 		    if (fio_flags & FIO_LATIN1)
1848 			u8c = *--p;
1849 		    else if (fio_flags & (FIO_UCS2 | FIO_UTF16))
1850 		    {
1851 			if (fio_flags & FIO_ENDIAN_L)
1852 			{
1853 			    u8c = (*--p << 8);
1854 			    u8c += *--p;
1855 			}
1856 			else
1857 			{
1858 			    u8c = *--p;
1859 			    u8c += (*--p << 8);
1860 			}
1861 			if ((fio_flags & FIO_UTF16)
1862 					    && u8c >= 0xdc00 && u8c <= 0xdfff)
1863 			{
1864 			    int u16c;
1865 
1866 			    if (p == ptr)
1867 			    {
1868 				/* Missing leading word. */
1869 				if (can_retry)
1870 				    goto rewind_retry;
1871 				if (conv_error == 0)
1872 				    conv_error = readfile_linenr(linecnt,
1873 								      ptr, p);
1874 				if (bad_char_behavior == BAD_DROP)
1875 				    continue;
1876 				if (bad_char_behavior != BAD_KEEP)
1877 				    u8c = bad_char_behavior;
1878 			    }
1879 
1880 			    /* found second word of double-word, get the first
1881 			     * word and compute the resulting character */
1882 			    if (fio_flags & FIO_ENDIAN_L)
1883 			    {
1884 				u16c = (*--p << 8);
1885 				u16c += *--p;
1886 			    }
1887 			    else
1888 			    {
1889 				u16c = *--p;
1890 				u16c += (*--p << 8);
1891 			    }
1892 			    u8c = 0x10000 + ((u16c & 0x3ff) << 10)
1893 							      + (u8c & 0x3ff);
1894 
1895 			    /* Check if the word is indeed a leading word. */
1896 			    if (u16c < 0xd800 || u16c > 0xdbff)
1897 			    {
1898 				if (can_retry)
1899 				    goto rewind_retry;
1900 				if (conv_error == 0)
1901 				    conv_error = readfile_linenr(linecnt,
1902 								      ptr, p);
1903 				if (bad_char_behavior == BAD_DROP)
1904 				    continue;
1905 				if (bad_char_behavior != BAD_KEEP)
1906 				    u8c = bad_char_behavior;
1907 			    }
1908 			}
1909 		    }
1910 		    else if (fio_flags & FIO_UCS4)
1911 		    {
1912 			if (fio_flags & FIO_ENDIAN_L)
1913 			{
1914 			    u8c = (unsigned)*--p << 24;
1915 			    u8c += (unsigned)*--p << 16;
1916 			    u8c += (unsigned)*--p << 8;
1917 			    u8c += *--p;
1918 			}
1919 			else	/* big endian */
1920 			{
1921 			    u8c = *--p;
1922 			    u8c += (unsigned)*--p << 8;
1923 			    u8c += (unsigned)*--p << 16;
1924 			    u8c += (unsigned)*--p << 24;
1925 			}
1926 		    }
1927 		    else    /* UTF-8 */
1928 		    {
1929 			if (*--p < 0x80)
1930 			    u8c = *p;
1931 			else
1932 			{
1933 			    len = utf_head_off(ptr, p);
1934 			    p -= len;
1935 			    u8c = utf_ptr2char(p);
1936 			    if (len == 0)
1937 			    {
1938 				/* Not a valid UTF-8 character, retry with
1939 				 * another fenc when possible, otherwise just
1940 				 * report the error. */
1941 				if (can_retry)
1942 				    goto rewind_retry;
1943 				if (conv_error == 0)
1944 				    conv_error = readfile_linenr(linecnt,
1945 								      ptr, p);
1946 				if (bad_char_behavior == BAD_DROP)
1947 				    continue;
1948 				if (bad_char_behavior != BAD_KEEP)
1949 				    u8c = bad_char_behavior;
1950 			    }
1951 			}
1952 		    }
1953 		    if (enc_utf8)	/* produce UTF-8 */
1954 		    {
1955 			dest -= utf_char2len(u8c);
1956 			(void)utf_char2bytes(u8c, dest);
1957 		    }
1958 		    else		/* produce Latin1 */
1959 		    {
1960 			--dest;
1961 			if (u8c >= 0x100)
1962 			{
1963 			    /* character doesn't fit in latin1, retry with
1964 			     * another fenc when possible, otherwise just
1965 			     * report the error. */
1966 			    if (can_retry)
1967 				goto rewind_retry;
1968 			    if (conv_error == 0)
1969 				conv_error = readfile_linenr(linecnt, ptr, p);
1970 			    if (bad_char_behavior == BAD_DROP)
1971 				++dest;
1972 			    else if (bad_char_behavior == BAD_KEEP)
1973 				*dest = u8c;
1974 			    else if (eap != NULL && eap->bad_char != 0)
1975 				*dest = bad_char_behavior;
1976 			    else
1977 				*dest = 0xBF;
1978 			}
1979 			else
1980 			    *dest = u8c;
1981 		    }
1982 		}
1983 
1984 		/* move the linerest to before the converted characters */
1985 		line_start = dest - linerest;
1986 		mch_memmove(line_start, buffer, (size_t)linerest);
1987 		size = (long)((ptr + real_size) - dest);
1988 		ptr = dest;
1989 	    }
1990 	    else if (enc_utf8 && !curbuf->b_p_bin)
1991 	    {
1992 		int  incomplete_tail = FALSE;
1993 
1994 		/* Reading UTF-8: Check if the bytes are valid UTF-8. */
1995 		for (p = ptr; ; ++p)
1996 		{
1997 		    int	 todo = (int)((ptr + size) - p);
1998 		    int	 l;
1999 
2000 		    if (todo <= 0)
2001 			break;
2002 		    if (*p >= 0x80)
2003 		    {
2004 			/* A length of 1 means it's an illegal byte.  Accept
2005 			 * an incomplete character at the end though, the next
2006 			 * read() will get the next bytes, we'll check it
2007 			 * then. */
2008 			l = utf_ptr2len_len(p, todo);
2009 			if (l > todo && !incomplete_tail)
2010 			{
2011 			    /* Avoid retrying with a different encoding when
2012 			     * a truncated file is more likely, or attempting
2013 			     * to read the rest of an incomplete sequence when
2014 			     * we have already done so. */
2015 			    if (p > ptr || filesize > 0)
2016 				incomplete_tail = TRUE;
2017 			    /* Incomplete byte sequence, move it to conv_rest[]
2018 			     * and try to read the rest of it, unless we've
2019 			     * already done so. */
2020 			    if (p > ptr)
2021 			    {
2022 				conv_restlen = todo;
2023 				mch_memmove(conv_rest, p, conv_restlen);
2024 				size -= conv_restlen;
2025 				break;
2026 			    }
2027 			}
2028 			if (l == 1 || l > todo)
2029 			{
2030 			    /* Illegal byte.  If we can try another encoding
2031 			     * do that, unless at EOF where a truncated
2032 			     * file is more likely than a conversion error. */
2033 			    if (can_retry && !incomplete_tail)
2034 				break;
2035 #ifdef USE_ICONV
2036 			    /* When we did a conversion report an error. */
2037 			    if (iconv_fd != (iconv_t)-1 && conv_error == 0)
2038 				conv_error = readfile_linenr(linecnt, ptr, p);
2039 #endif
2040 			    /* Remember the first linenr with an illegal byte */
2041 			    if (conv_error == 0 && illegal_byte == 0)
2042 				illegal_byte = readfile_linenr(linecnt, ptr, p);
2043 
2044 			    /* Drop, keep or replace the bad byte. */
2045 			    if (bad_char_behavior == BAD_DROP)
2046 			    {
2047 				mch_memmove(p, p + 1, todo - 1);
2048 				--p;
2049 				--size;
2050 			    }
2051 			    else if (bad_char_behavior != BAD_KEEP)
2052 				*p = bad_char_behavior;
2053 			}
2054 			else
2055 			    p += l - 1;
2056 		    }
2057 		}
2058 		if (p < ptr + size && !incomplete_tail)
2059 		{
2060 		    /* Detected a UTF-8 error. */
2061 rewind_retry:
2062 		    /* Retry reading with another conversion. */
2063 #if defined(FEAT_EVAL) && defined(USE_ICONV)
2064 		    if (*p_ccv != NUL && iconv_fd != (iconv_t)-1)
2065 			/* iconv() failed, try 'charconvert' */
2066 			did_iconv = TRUE;
2067 		    else
2068 #endif
2069 			/* use next item from 'fileencodings' */
2070 			advance_fenc = TRUE;
2071 		    file_rewind = TRUE;
2072 		    goto retry;
2073 		}
2074 	    }
2075 
2076 	    /* count the number of characters (after conversion!) */
2077 	    filesize += size;
2078 
2079 	    /*
2080 	     * when reading the first part of a file: guess EOL type
2081 	     */
2082 	    if (fileformat == EOL_UNKNOWN)
2083 	    {
2084 		/* First try finding a NL, for Dos and Unix */
2085 		if (try_dos || try_unix)
2086 		{
2087 		    /* Reset the carriage return counter. */
2088 		    if (try_mac)
2089 			try_mac = 1;
2090 
2091 		    for (p = ptr; p < ptr + size; ++p)
2092 		    {
2093 			if (*p == NL)
2094 			{
2095 			    if (!try_unix
2096 				    || (try_dos && p > ptr && p[-1] == CAR))
2097 				fileformat = EOL_DOS;
2098 			    else
2099 				fileformat = EOL_UNIX;
2100 			    break;
2101 			}
2102 			else if (*p == CAR && try_mac)
2103 			    try_mac++;
2104 		    }
2105 
2106 		    /* Don't give in to EOL_UNIX if EOL_MAC is more likely */
2107 		    if (fileformat == EOL_UNIX && try_mac)
2108 		    {
2109 			/* Need to reset the counters when retrying fenc. */
2110 			try_mac = 1;
2111 			try_unix = 1;
2112 			for (; p >= ptr && *p != CAR; p--)
2113 			    ;
2114 			if (p >= ptr)
2115 			{
2116 			    for (p = ptr; p < ptr + size; ++p)
2117 			    {
2118 				if (*p == NL)
2119 				    try_unix++;
2120 				else if (*p == CAR)
2121 				    try_mac++;
2122 			    }
2123 			    if (try_mac > try_unix)
2124 				fileformat = EOL_MAC;
2125 			}
2126 		    }
2127 		    else if (fileformat == EOL_UNKNOWN && try_mac == 1)
2128 			/* Looking for CR but found no end-of-line markers at
2129 			 * all: use the default format. */
2130 			fileformat = default_fileformat();
2131 		}
2132 
2133 		/* No NL found: may use Mac format */
2134 		if (fileformat == EOL_UNKNOWN && try_mac)
2135 		    fileformat = EOL_MAC;
2136 
2137 		/* Still nothing found?  Use first format in 'ffs' */
2138 		if (fileformat == EOL_UNKNOWN)
2139 		    fileformat = default_fileformat();
2140 
2141 		/* if editing a new file: may set p_tx and p_ff */
2142 		if (set_options)
2143 		    set_fileformat(fileformat, OPT_LOCAL);
2144 	    }
2145 	}
2146 
2147 	/*
2148 	 * This loop is executed once for every character read.
2149 	 * Keep it fast!
2150 	 */
2151 	if (fileformat == EOL_MAC)
2152 	{
2153 	    --ptr;
2154 	    while (++ptr, --size >= 0)
2155 	    {
2156 		/* catch most common case first */
2157 		if ((c = *ptr) != NUL && c != CAR && c != NL)
2158 		    continue;
2159 		if (c == NUL)
2160 		    *ptr = NL;	/* NULs are replaced by newlines! */
2161 		else if (c == NL)
2162 		    *ptr = CAR;	/* NLs are replaced by CRs! */
2163 		else
2164 		{
2165 		    if (skip_count == 0)
2166 		    {
2167 			*ptr = NUL;	    /* end of line */
2168 			len = (colnr_T) (ptr - line_start + 1);
2169 			if (ml_append(lnum, line_start, len, newfile) == FAIL)
2170 			{
2171 			    error = TRUE;
2172 			    break;
2173 			}
2174 #ifdef FEAT_PERSISTENT_UNDO
2175 			if (read_undo_file)
2176 			    sha256_update(&sha_ctx, line_start, len);
2177 #endif
2178 			++lnum;
2179 			if (--read_count == 0)
2180 			{
2181 			    error = TRUE;	/* break loop */
2182 			    line_start = ptr;	/* nothing left to write */
2183 			    break;
2184 			}
2185 		    }
2186 		    else
2187 			--skip_count;
2188 		    line_start = ptr + 1;
2189 		}
2190 	    }
2191 	}
2192 	else
2193 	{
2194 	    --ptr;
2195 	    while (++ptr, --size >= 0)
2196 	    {
2197 		if ((c = *ptr) != NUL && c != NL)  /* catch most common case */
2198 		    continue;
2199 		if (c == NUL)
2200 		    *ptr = NL;	/* NULs are replaced by newlines! */
2201 		else
2202 		{
2203 		    if (skip_count == 0)
2204 		    {
2205 			*ptr = NUL;		/* end of line */
2206 			len = (colnr_T)(ptr - line_start + 1);
2207 			if (fileformat == EOL_DOS)
2208 			{
2209 			    if (ptr > line_start && ptr[-1] == CAR)
2210 			    {
2211 				/* remove CR before NL */
2212 				ptr[-1] = NUL;
2213 				--len;
2214 			    }
2215 			    /*
2216 			     * Reading in Dos format, but no CR-LF found!
2217 			     * When 'fileformats' includes "unix", delete all
2218 			     * the lines read so far and start all over again.
2219 			     * Otherwise give an error message later.
2220 			     */
2221 			    else if (ff_error != EOL_DOS)
2222 			    {
2223 				if (   try_unix
2224 				    && !read_stdin
2225 				    && (read_buffer
2226 					|| vim_lseek(fd, (off_T)0L, SEEK_SET)
2227 									  == 0))
2228 				{
2229 				    fileformat = EOL_UNIX;
2230 				    if (set_options)
2231 					set_fileformat(EOL_UNIX, OPT_LOCAL);
2232 				    file_rewind = TRUE;
2233 				    keep_fileformat = TRUE;
2234 				    goto retry;
2235 				}
2236 				ff_error = EOL_DOS;
2237 			    }
2238 			}
2239 			if (ml_append(lnum, line_start, len, newfile) == FAIL)
2240 			{
2241 			    error = TRUE;
2242 			    break;
2243 			}
2244 #ifdef FEAT_PERSISTENT_UNDO
2245 			if (read_undo_file)
2246 			    sha256_update(&sha_ctx, line_start, len);
2247 #endif
2248 			++lnum;
2249 			if (--read_count == 0)
2250 			{
2251 			    error = TRUE;	    /* break loop */
2252 			    line_start = ptr;	/* nothing left to write */
2253 			    break;
2254 			}
2255 		    }
2256 		    else
2257 			--skip_count;
2258 		    line_start = ptr + 1;
2259 		}
2260 	    }
2261 	}
2262 	linerest = (long)(ptr - line_start);
2263 	ui_breakcheck();
2264     }
2265 
2266 failed:
2267     /* not an error, max. number of lines reached */
2268     if (error && read_count == 0)
2269 	error = FALSE;
2270 
2271     /*
2272      * If we get EOF in the middle of a line, note the fact and
2273      * complete the line ourselves.
2274      * In Dos format ignore a trailing CTRL-Z, unless 'binary' set.
2275      */
2276     if (!error
2277 	    && !got_int
2278 	    && linerest != 0
2279 	    && !(!curbuf->b_p_bin
2280 		&& fileformat == EOL_DOS
2281 		&& *line_start == Ctrl_Z
2282 		&& ptr == line_start + 1))
2283     {
2284 	/* remember for when writing */
2285 	if (set_options)
2286 	    curbuf->b_p_eol = FALSE;
2287 	*ptr = NUL;
2288 	len = (colnr_T)(ptr - line_start + 1);
2289 	if (ml_append(lnum, line_start, len, newfile) == FAIL)
2290 	    error = TRUE;
2291 	else
2292 	{
2293 #ifdef FEAT_PERSISTENT_UNDO
2294 	    if (read_undo_file)
2295 		sha256_update(&sha_ctx, line_start, len);
2296 #endif
2297 	    read_no_eol_lnum = ++lnum;
2298 	}
2299     }
2300 
2301     if (set_options)
2302 	save_file_ff(curbuf);		/* remember the current file format */
2303 
2304 #ifdef FEAT_CRYPT
2305     if (curbuf->b_cryptstate != NULL)
2306     {
2307 	crypt_free_state(curbuf->b_cryptstate);
2308 	curbuf->b_cryptstate = NULL;
2309     }
2310     if (cryptkey != NULL && cryptkey != curbuf->b_p_key)
2311 	crypt_free_key(cryptkey);
2312     /* Don't set cryptkey to NULL, it's used below as a flag that
2313      * encryption was used. */
2314 #endif
2315 
2316     /* If editing a new file: set 'fenc' for the current buffer.
2317      * Also for ":read ++edit file". */
2318     if (set_options)
2319 	set_string_option_direct((char_u *)"fenc", -1, fenc,
2320 						       OPT_FREE|OPT_LOCAL, 0);
2321     if (fenc_alloced)
2322 	vim_free(fenc);
2323 #ifdef USE_ICONV
2324     if (iconv_fd != (iconv_t)-1)
2325 	iconv_close(iconv_fd);
2326 #endif
2327 
2328     if (!read_buffer && !read_stdin)
2329 	close(fd);				/* errors are ignored */
2330 #ifdef HAVE_FD_CLOEXEC
2331     else
2332     {
2333 	int fdflags = fcntl(fd, F_GETFD);
2334 	if (fdflags >= 0 && (fdflags & FD_CLOEXEC) == 0)
2335 	    (void)fcntl(fd, F_SETFD, fdflags | FD_CLOEXEC);
2336     }
2337 #endif
2338     vim_free(buffer);
2339 
2340 #ifdef HAVE_DUP
2341     if (read_stdin)
2342     {
2343 	/* Use stderr for stdin, makes shell commands work. */
2344 	close(0);
2345 	vim_ignored = dup(2);
2346     }
2347 #endif
2348 
2349     if (tmpname != NULL)
2350     {
2351 	mch_remove(tmpname);		/* delete converted file */
2352 	vim_free(tmpname);
2353     }
2354     --no_wait_return;			/* may wait for return now */
2355 
2356     /*
2357      * In recovery mode everything but autocommands is skipped.
2358      */
2359     if (!recoverymode)
2360     {
2361 	/* need to delete the last line, which comes from the empty buffer */
2362 	if (newfile && wasempty && !(curbuf->b_ml.ml_flags & ML_EMPTY))
2363 	{
2364 #ifdef FEAT_NETBEANS_INTG
2365 	    netbeansFireChanges = 0;
2366 #endif
2367 	    ml_delete(curbuf->b_ml.ml_line_count, FALSE);
2368 #ifdef FEAT_NETBEANS_INTG
2369 	    netbeansFireChanges = 1;
2370 #endif
2371 	    --linecnt;
2372 	}
2373 	linecnt = curbuf->b_ml.ml_line_count - linecnt;
2374 	if (filesize == 0)
2375 	    linecnt = 0;
2376 	if (newfile || read_buffer)
2377 	{
2378 	    redraw_curbuf_later(NOT_VALID);
2379 #ifdef FEAT_DIFF
2380 	    /* After reading the text into the buffer the diff info needs to
2381 	     * be updated. */
2382 	    diff_invalidate(curbuf);
2383 #endif
2384 #ifdef FEAT_FOLDING
2385 	    /* All folds in the window are invalid now.  Mark them for update
2386 	     * before triggering autocommands. */
2387 	    foldUpdateAll(curwin);
2388 #endif
2389 	}
2390 	else if (linecnt)		/* appended at least one line */
2391 	    appended_lines_mark(from, linecnt);
2392 
2393 #ifndef ALWAYS_USE_GUI
2394 	/*
2395 	 * If we were reading from the same terminal as where messages go,
2396 	 * the screen will have been messed up.
2397 	 * Switch on raw mode now and clear the screen.
2398 	 */
2399 	if (read_stdin)
2400 	{
2401 	    settmode(TMODE_RAW);	/* set to raw mode */
2402 	    starttermcap();
2403 	    screenclear();
2404 	}
2405 #endif
2406 
2407 	if (got_int)
2408 	{
2409 	    if (!(flags & READ_DUMMY))
2410 	    {
2411 		filemess(curbuf, sfname, (char_u *)_(e_interr), 0);
2412 		if (newfile)
2413 		    curbuf->b_p_ro = TRUE;	/* must use "w!" now */
2414 	    }
2415 	    msg_scroll = msg_save;
2416 #ifdef FEAT_VIMINFO
2417 	    check_marks_read();
2418 #endif
2419 	    return OK;		/* an interrupt isn't really an error */
2420 	}
2421 
2422 	if (!filtering && !(flags & READ_DUMMY))
2423 	{
2424 	    msg_add_fname(curbuf, sfname);   /* fname in IObuff with quotes */
2425 	    c = FALSE;
2426 
2427 #ifdef UNIX
2428 	    if (S_ISFIFO(perm))			    /* fifo */
2429 	    {
2430 		STRCAT(IObuff, _("[fifo]"));
2431 		c = TRUE;
2432 	    }
2433 	    if (S_ISSOCK(perm))			    /* or socket */
2434 	    {
2435 		STRCAT(IObuff, _("[socket]"));
2436 		c = TRUE;
2437 	    }
2438 # ifdef OPEN_CHR_FILES
2439 	    if (S_ISCHR(perm))			    /* or character special */
2440 	    {
2441 		STRCAT(IObuff, _("[character special]"));
2442 		c = TRUE;
2443 	    }
2444 # endif
2445 #endif
2446 	    if (curbuf->b_p_ro)
2447 	    {
2448 		STRCAT(IObuff, shortmess(SHM_RO) ? _("[RO]") : _("[readonly]"));
2449 		c = TRUE;
2450 	    }
2451 	    if (read_no_eol_lnum)
2452 	    {
2453 		msg_add_eol();
2454 		c = TRUE;
2455 	    }
2456 	    if (ff_error == EOL_DOS)
2457 	    {
2458 		STRCAT(IObuff, _("[CR missing]"));
2459 		c = TRUE;
2460 	    }
2461 	    if (split)
2462 	    {
2463 		STRCAT(IObuff, _("[long lines split]"));
2464 		c = TRUE;
2465 	    }
2466 	    if (notconverted)
2467 	    {
2468 		STRCAT(IObuff, _("[NOT converted]"));
2469 		c = TRUE;
2470 	    }
2471 	    else if (converted)
2472 	    {
2473 		STRCAT(IObuff, _("[converted]"));
2474 		c = TRUE;
2475 	    }
2476 #ifdef FEAT_CRYPT
2477 	    if (cryptkey != NULL)
2478 	    {
2479 		crypt_append_msg(curbuf);
2480 		c = TRUE;
2481 	    }
2482 #endif
2483 	    if (conv_error != 0)
2484 	    {
2485 		sprintf((char *)IObuff + STRLEN(IObuff),
2486 		       _("[CONVERSION ERROR in line %ld]"), (long)conv_error);
2487 		c = TRUE;
2488 	    }
2489 	    else if (illegal_byte > 0)
2490 	    {
2491 		sprintf((char *)IObuff + STRLEN(IObuff),
2492 			 _("[ILLEGAL BYTE in line %ld]"), (long)illegal_byte);
2493 		c = TRUE;
2494 	    }
2495 	    else if (error)
2496 	    {
2497 		STRCAT(IObuff, _("[READ ERRORS]"));
2498 		c = TRUE;
2499 	    }
2500 	    if (msg_add_fileformat(fileformat))
2501 		c = TRUE;
2502 #ifdef FEAT_CRYPT
2503 	    if (cryptkey != NULL)
2504 		msg_add_lines(c, (long)linecnt, filesize
2505 			 - crypt_get_header_len(crypt_get_method_nr(curbuf)));
2506 	    else
2507 #endif
2508 		msg_add_lines(c, (long)linecnt, filesize);
2509 
2510 	    VIM_CLEAR(keep_msg);
2511 	    msg_scrolled_ign = TRUE;
2512 #ifdef ALWAYS_USE_GUI
2513 	    /* Don't show the message when reading stdin, it would end up in a
2514 	     * message box (which might be shown when exiting!) */
2515 	    if (read_stdin || read_buffer)
2516 		p = msg_may_trunc(FALSE, IObuff);
2517 	    else
2518 #endif
2519 		p = (char_u *)msg_trunc_attr((char *)IObuff, FALSE, 0);
2520 	    if (read_stdin || read_buffer || restart_edit != 0
2521 		    || (msg_scrolled != 0 && !need_wait_return))
2522 		/* Need to repeat the message after redrawing when:
2523 		 * - When reading from stdin (the screen will be cleared next).
2524 		 * - When restart_edit is set (otherwise there will be a delay
2525 		 *   before redrawing).
2526 		 * - When the screen was scrolled but there is no wait-return
2527 		 *   prompt. */
2528 		set_keep_msg(p, 0);
2529 	    msg_scrolled_ign = FALSE;
2530 	}
2531 
2532 	/* with errors writing the file requires ":w!" */
2533 	if (newfile && (error
2534 		    || conv_error != 0
2535 		    || (illegal_byte > 0 && bad_char_behavior != BAD_KEEP)))
2536 	    curbuf->b_p_ro = TRUE;
2537 
2538 	u_clearline();	    /* cannot use "U" command after adding lines */
2539 
2540 	/*
2541 	 * In Ex mode: cursor at last new line.
2542 	 * Otherwise: cursor at first new line.
2543 	 */
2544 	if (exmode_active)
2545 	    curwin->w_cursor.lnum = from + linecnt;
2546 	else
2547 	    curwin->w_cursor.lnum = from + 1;
2548 	check_cursor_lnum();
2549 	beginline(BL_WHITE | BL_FIX);	    /* on first non-blank */
2550 
2551 	/*
2552 	 * Set '[ and '] marks to the newly read lines.
2553 	 */
2554 	curbuf->b_op_start.lnum = from + 1;
2555 	curbuf->b_op_start.col = 0;
2556 	curbuf->b_op_end.lnum = from + linecnt;
2557 	curbuf->b_op_end.col = 0;
2558 
2559 #ifdef MSWIN
2560 	/*
2561 	 * Work around a weird problem: When a file has two links (only
2562 	 * possible on NTFS) and we write through one link, then stat() it
2563 	 * through the other link, the timestamp information may be wrong.
2564 	 * It's correct again after reading the file, thus reset the timestamp
2565 	 * here.
2566 	 */
2567 	if (newfile && !read_stdin && !read_buffer
2568 					 && mch_stat((char *)fname, &st) >= 0)
2569 	{
2570 	    buf_store_time(curbuf, &st, fname);
2571 	    curbuf->b_mtime_read = curbuf->b_mtime;
2572 	}
2573 #endif
2574     }
2575     msg_scroll = msg_save;
2576 
2577 #ifdef FEAT_VIMINFO
2578     /*
2579      * Get the marks before executing autocommands, so they can be used there.
2580      */
2581     check_marks_read();
2582 #endif
2583 
2584     /*
2585      * We remember if the last line of the read didn't have
2586      * an eol even when 'binary' is off, to support turning 'fixeol' off,
2587      * or writing the read again with 'binary' on.  The latter is required
2588      * for ":autocmd FileReadPost *.gz set bin|'[,']!gunzip" to work.
2589      */
2590     curbuf->b_no_eol_lnum = read_no_eol_lnum;
2591 
2592     /* When reloading a buffer put the cursor at the first line that is
2593      * different. */
2594     if (flags & READ_KEEP_UNDO)
2595 	u_find_first_changed();
2596 
2597 #ifdef FEAT_PERSISTENT_UNDO
2598     /*
2599      * When opening a new file locate undo info and read it.
2600      */
2601     if (read_undo_file)
2602     {
2603 	char_u	hash[UNDO_HASH_SIZE];
2604 
2605 	sha256_finish(&sha_ctx, hash);
2606 	u_read_undo(NULL, hash, fname);
2607     }
2608 #endif
2609 
2610     if (!read_stdin && !read_fifo && (!read_buffer || sfname != NULL))
2611     {
2612 	int m = msg_scroll;
2613 	int n = msg_scrolled;
2614 
2615 	/* Save the fileformat now, otherwise the buffer will be considered
2616 	 * modified if the format/encoding was automatically detected. */
2617 	if (set_options)
2618 	    save_file_ff(curbuf);
2619 
2620 	/*
2621 	 * The output from the autocommands should not overwrite anything and
2622 	 * should not be overwritten: Set msg_scroll, restore its value if no
2623 	 * output was done.
2624 	 */
2625 	msg_scroll = TRUE;
2626 	if (filtering)
2627 	    apply_autocmds_exarg(EVENT_FILTERREADPOST, NULL, sfname,
2628 							  FALSE, curbuf, eap);
2629 	else if (newfile || (read_buffer && sfname != NULL))
2630 	{
2631 	    apply_autocmds_exarg(EVENT_BUFREADPOST, NULL, sfname,
2632 							  FALSE, curbuf, eap);
2633 	    if (!au_did_filetype && *curbuf->b_p_ft != NUL)
2634 		/*
2635 		 * EVENT_FILETYPE was not triggered but the buffer already has a
2636 		 * filetype. Trigger EVENT_FILETYPE using the existing filetype.
2637 		 */
2638 		apply_autocmds(EVENT_FILETYPE, curbuf->b_p_ft, curbuf->b_fname,
2639 			TRUE, curbuf);
2640 	}
2641 	else
2642 	    apply_autocmds_exarg(EVENT_FILEREADPOST, sfname, sfname,
2643 							    FALSE, NULL, eap);
2644 	if (msg_scrolled == n)
2645 	    msg_scroll = m;
2646 # ifdef FEAT_EVAL
2647 	if (aborting())	    /* autocmds may abort script processing */
2648 	    return FAIL;
2649 # endif
2650     }
2651 
2652     if (recoverymode && error)
2653 	return FAIL;
2654     return OK;
2655 }
2656 
2657 #if defined(OPEN_CHR_FILES) || defined(PROTO)
2658 /*
2659  * Returns TRUE if the file name argument is of the form "/dev/fd/\d\+",
2660  * which is the name of files used for process substitution output by
2661  * some shells on some operating systems, e.g., bash on SunOS.
2662  * Do not accept "/dev/fd/[012]", opening these may hang Vim.
2663  */
2664     int
2665 is_dev_fd_file(char_u *fname)
2666 {
2667     return (STRNCMP(fname, "/dev/fd/", 8) == 0
2668 	    && VIM_ISDIGIT(fname[8])
2669 	    && *skipdigits(fname + 9) == NUL
2670 	    && (fname[9] != NUL
2671 		|| (fname[8] != '0' && fname[8] != '1' && fname[8] != '2')));
2672 }
2673 #endif
2674 
2675 /*
2676  * From the current line count and characters read after that, estimate the
2677  * line number where we are now.
2678  * Used for error messages that include a line number.
2679  */
2680     static linenr_T
2681 readfile_linenr(
2682     linenr_T	linecnt,	/* line count before reading more bytes */
2683     char_u	*p,		/* start of more bytes read */
2684     char_u	*endp)		/* end of more bytes read */
2685 {
2686     char_u	*s;
2687     linenr_T	lnum;
2688 
2689     lnum = curbuf->b_ml.ml_line_count - linecnt + 1;
2690     for (s = p; s < endp; ++s)
2691 	if (*s == '\n')
2692 	    ++lnum;
2693     return lnum;
2694 }
2695 
2696 /*
2697  * Fill "*eap" to force the 'fileencoding', 'fileformat' and 'binary to be
2698  * equal to the buffer "buf".  Used for calling readfile().
2699  * Returns OK or FAIL.
2700  */
2701     int
2702 prep_exarg(exarg_T *eap, buf_T *buf)
2703 {
2704     eap->cmd = alloc(15 + (unsigned)STRLEN(buf->b_p_fenc));
2705     if (eap->cmd == NULL)
2706 	return FAIL;
2707 
2708     sprintf((char *)eap->cmd, "e ++enc=%s", buf->b_p_fenc);
2709     eap->force_enc = 8;
2710     eap->bad_char = buf->b_bad_char;
2711     eap->force_ff = *buf->b_p_ff;
2712 
2713     eap->force_bin = buf->b_p_bin ? FORCE_BIN : FORCE_NOBIN;
2714     eap->read_edit = FALSE;
2715     eap->forceit = FALSE;
2716     return OK;
2717 }
2718 
2719 /*
2720  * Set default or forced 'fileformat' and 'binary'.
2721  */
2722     void
2723 set_file_options(int set_options, exarg_T *eap)
2724 {
2725     /* set default 'fileformat' */
2726     if (set_options)
2727     {
2728 	if (eap != NULL && eap->force_ff != 0)
2729 	    set_fileformat(get_fileformat_force(curbuf, eap), OPT_LOCAL);
2730 	else if (*p_ffs != NUL)
2731 	    set_fileformat(default_fileformat(), OPT_LOCAL);
2732     }
2733 
2734     /* set or reset 'binary' */
2735     if (eap != NULL && eap->force_bin != 0)
2736     {
2737 	int	oldval = curbuf->b_p_bin;
2738 
2739 	curbuf->b_p_bin = (eap->force_bin == FORCE_BIN);
2740 	set_options_bin(oldval, curbuf->b_p_bin, OPT_LOCAL);
2741     }
2742 }
2743 
2744 /*
2745  * Set forced 'fileencoding'.
2746  */
2747     void
2748 set_forced_fenc(exarg_T *eap)
2749 {
2750     if (eap->force_enc != 0)
2751     {
2752 	char_u *fenc = enc_canonize(eap->cmd + eap->force_enc);
2753 
2754 	if (fenc != NULL)
2755 	    set_string_option_direct((char_u *)"fenc", -1,
2756 				 fenc, OPT_FREE|OPT_LOCAL, 0);
2757 	vim_free(fenc);
2758     }
2759 }
2760 
2761 /*
2762  * Find next fileencoding to use from 'fileencodings'.
2763  * "pp" points to fenc_next.  It's advanced to the next item.
2764  * When there are no more items, an empty string is returned and *pp is set to
2765  * NULL.
2766  * When *pp is not set to NULL, the result is in allocated memory.
2767  */
2768     static char_u *
2769 next_fenc(char_u **pp)
2770 {
2771     char_u	*p;
2772     char_u	*r;
2773 
2774     if (**pp == NUL)
2775     {
2776 	*pp = NULL;
2777 	return (char_u *)"";
2778     }
2779     p = vim_strchr(*pp, ',');
2780     if (p == NULL)
2781     {
2782 	r = enc_canonize(*pp);
2783 	*pp += STRLEN(*pp);
2784     }
2785     else
2786     {
2787 	r = vim_strnsave(*pp, (int)(p - *pp));
2788 	*pp = p + 1;
2789 	if (r != NULL)
2790 	{
2791 	    p = enc_canonize(r);
2792 	    vim_free(r);
2793 	    r = p;
2794 	}
2795     }
2796     if (r == NULL)	/* out of memory */
2797     {
2798 	r = (char_u *)"";
2799 	*pp = NULL;
2800     }
2801     return r;
2802 }
2803 
2804 #ifdef FEAT_EVAL
2805 /*
2806  * Convert a file with the 'charconvert' expression.
2807  * This closes the file which is to be read, converts it and opens the
2808  * resulting file for reading.
2809  * Returns name of the resulting converted file (the caller should delete it
2810  * after reading it).
2811  * Returns NULL if the conversion failed ("*fdp" is not set) .
2812  */
2813     static char_u *
2814 readfile_charconvert(
2815     char_u	*fname,		/* name of input file */
2816     char_u	*fenc,		/* converted from */
2817     int		*fdp)		/* in/out: file descriptor of file */
2818 {
2819     char_u	*tmpname;
2820     char	*errmsg = NULL;
2821 
2822     tmpname = vim_tempname('r', FALSE);
2823     if (tmpname == NULL)
2824 	errmsg = _("Can't find temp file for conversion");
2825     else
2826     {
2827 	close(*fdp);		/* close the input file, ignore errors */
2828 	*fdp = -1;
2829 	if (eval_charconvert(fenc, enc_utf8 ? (char_u *)"utf-8" : p_enc,
2830 						      fname, tmpname) == FAIL)
2831 	    errmsg = _("Conversion with 'charconvert' failed");
2832 	if (errmsg == NULL && (*fdp = mch_open((char *)tmpname,
2833 						  O_RDONLY | O_EXTRA, 0)) < 0)
2834 	    errmsg = _("can't read output of 'charconvert'");
2835     }
2836 
2837     if (errmsg != NULL)
2838     {
2839 	/* Don't use emsg(), it breaks mappings, the retry with
2840 	 * another type of conversion might still work. */
2841 	msg(errmsg);
2842 	if (tmpname != NULL)
2843 	{
2844 	    mch_remove(tmpname);	/* delete converted file */
2845 	    VIM_CLEAR(tmpname);
2846 	}
2847     }
2848 
2849     /* If the input file is closed, open it (caller should check for error). */
2850     if (*fdp < 0)
2851 	*fdp = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0);
2852 
2853     return tmpname;
2854 }
2855 #endif
2856 
2857 
2858 #ifdef FEAT_VIMINFO
2859 /*
2860  * Read marks for the current buffer from the viminfo file, when we support
2861  * buffer marks and the buffer has a name.
2862  */
2863     static void
2864 check_marks_read(void)
2865 {
2866     if (!curbuf->b_marks_read && get_viminfo_parameter('\'') > 0
2867 						  && curbuf->b_ffname != NULL)
2868 	read_viminfo(NULL, VIF_WANT_MARKS);
2869 
2870     /* Always set b_marks_read; needed when 'viminfo' is changed to include
2871      * the ' parameter after opening a buffer. */
2872     curbuf->b_marks_read = TRUE;
2873 }
2874 #endif
2875 
2876 #if defined(FEAT_CRYPT) || defined(PROTO)
2877 /*
2878  * Check for magic number used for encryption.  Applies to the current buffer.
2879  * If found, the magic number is removed from ptr[*sizep] and *sizep and
2880  * *filesizep are updated.
2881  * Return the (new) encryption key, NULL for no encryption.
2882  */
2883     static char_u *
2884 check_for_cryptkey(
2885     char_u	*cryptkey,	/* previous encryption key or NULL */
2886     char_u	*ptr,		/* pointer to read bytes */
2887     long	*sizep,		/* length of read bytes */
2888     off_T	*filesizep,	/* nr of bytes used from file */
2889     int		newfile,	/* editing a new buffer */
2890     char_u	*fname,		/* file name to display */
2891     int		*did_ask)	/* flag: whether already asked for key */
2892 {
2893     int method = crypt_method_nr_from_magic((char *)ptr, *sizep);
2894     int b_p_ro = curbuf->b_p_ro;
2895 
2896     if (method >= 0)
2897     {
2898 	/* Mark the buffer as read-only until the decryption has taken place.
2899 	 * Avoids accidentally overwriting the file with garbage. */
2900 	curbuf->b_p_ro = TRUE;
2901 
2902 	/* Set the cryptmethod local to the buffer. */
2903 	crypt_set_cm_option(curbuf, method);
2904 	if (cryptkey == NULL && !*did_ask)
2905 	{
2906 	    if (*curbuf->b_p_key)
2907 		cryptkey = curbuf->b_p_key;
2908 	    else
2909 	    {
2910 		/* When newfile is TRUE, store the typed key in the 'key'
2911 		 * option and don't free it.  bf needs hash of the key saved.
2912 		 * Don't ask for the key again when first time Enter was hit.
2913 		 * Happens when retrying to detect encoding. */
2914 		smsg(_(need_key_msg), fname);
2915 		msg_scroll = TRUE;
2916 		crypt_check_method(method);
2917 		cryptkey = crypt_get_key(newfile, FALSE);
2918 		*did_ask = TRUE;
2919 
2920 		/* check if empty key entered */
2921 		if (cryptkey != NULL && *cryptkey == NUL)
2922 		{
2923 		    if (cryptkey != curbuf->b_p_key)
2924 			vim_free(cryptkey);
2925 		    cryptkey = NULL;
2926 		}
2927 	    }
2928 	}
2929 
2930 	if (cryptkey != NULL)
2931 	{
2932 	    int header_len;
2933 
2934 	    curbuf->b_cryptstate = crypt_create_from_header(
2935 						       method, cryptkey, ptr);
2936 	    crypt_set_cm_option(curbuf, method);
2937 
2938 	    /* Remove cryptmethod specific header from the text. */
2939 	    header_len = crypt_get_header_len(method);
2940 	    if (*sizep <= header_len)
2941 		/* invalid header, buffer can't be encrypted */
2942 		return NULL;
2943 	    *filesizep += header_len;
2944 	    *sizep -= header_len;
2945 	    mch_memmove(ptr, ptr + header_len, (size_t)*sizep);
2946 
2947 	    /* Restore the read-only flag. */
2948 	    curbuf->b_p_ro = b_p_ro;
2949 	}
2950     }
2951     /* When starting to edit a new file which does not have encryption, clear
2952      * the 'key' option, except when starting up (called with -x argument) */
2953     else if (newfile && *curbuf->b_p_key != NUL && !starting)
2954 	set_option_value((char_u *)"key", 0L, (char_u *)"", OPT_LOCAL);
2955 
2956     return cryptkey;
2957 }
2958 #endif  /* FEAT_CRYPT */
2959 
2960 #ifdef UNIX
2961     static void
2962 set_file_time(
2963     char_u  *fname,
2964     time_t  atime,	    /* access time */
2965     time_t  mtime)	    /* modification time */
2966 {
2967 # if defined(HAVE_UTIME) && defined(HAVE_UTIME_H)
2968     struct utimbuf  buf;
2969 
2970     buf.actime	= atime;
2971     buf.modtime	= mtime;
2972     (void)utime((char *)fname, &buf);
2973 # else
2974 #  if defined(HAVE_UTIMES)
2975     struct timeval  tvp[2];
2976 
2977     tvp[0].tv_sec   = atime;
2978     tvp[0].tv_usec  = 0;
2979     tvp[1].tv_sec   = mtime;
2980     tvp[1].tv_usec  = 0;
2981 #   ifdef NeXT
2982     (void)utimes((char *)fname, tvp);
2983 #   else
2984     (void)utimes((char *)fname, (const struct timeval *)&tvp);
2985 #   endif
2986 #  endif
2987 # endif
2988 }
2989 #endif /* UNIX */
2990 
2991 #if defined(VMS) && !defined(MIN)
2992 /* Older DECC compiler for VAX doesn't define MIN() */
2993 # define MIN(a, b) ((a) < (b) ? (a) : (b))
2994 #endif
2995 
2996 /*
2997  * Return TRUE if a file appears to be read-only from the file permissions.
2998  */
2999     int
3000 check_file_readonly(
3001     char_u	*fname,		/* full path to file */
3002     int		perm)		/* known permissions on file */
3003 {
3004 #ifndef USE_MCH_ACCESS
3005     int	    fd = 0;
3006 #endif
3007 
3008     return (
3009 #ifdef USE_MCH_ACCESS
3010 # ifdef UNIX
3011 	(perm & 0222) == 0 ||
3012 # endif
3013 	mch_access((char *)fname, W_OK)
3014 #else
3015 	(fd = mch_open((char *)fname, O_RDWR | O_EXTRA, 0)) < 0
3016 					? TRUE : (close(fd), FALSE)
3017 #endif
3018 	);
3019 }
3020 
3021 
3022 /*
3023  * buf_write() - write to file "fname" lines "start" through "end"
3024  *
3025  * We do our own buffering here because fwrite() is so slow.
3026  *
3027  * If "forceit" is true, we don't care for errors when attempting backups.
3028  * In case of an error everything possible is done to restore the original
3029  * file.  But when "forceit" is TRUE, we risk losing it.
3030  *
3031  * When "reset_changed" is TRUE and "append" == FALSE and "start" == 1 and
3032  * "end" == curbuf->b_ml.ml_line_count, reset curbuf->b_changed.
3033  *
3034  * This function must NOT use NameBuff (because it's called by autowrite()).
3035  *
3036  * return FAIL for failure, OK otherwise
3037  */
3038     int
3039 buf_write(
3040     buf_T	    *buf,
3041     char_u	    *fname,
3042     char_u	    *sfname,
3043     linenr_T	    start,
3044     linenr_T	    end,
3045     exarg_T	    *eap,		/* for forced 'ff' and 'fenc', can be
3046 					   NULL! */
3047     int		    append,		/* append to the file */
3048     int		    forceit,
3049     int		    reset_changed,
3050     int		    filtering)
3051 {
3052     int		    fd;
3053     char_u	    *backup = NULL;
3054     int		    backup_copy = FALSE; /* copy the original file? */
3055     int		    dobackup;
3056     char_u	    *ffname;
3057     char_u	    *wfname = NULL;	/* name of file to write to */
3058     char_u	    *s;
3059     char_u	    *ptr;
3060     char_u	    c;
3061     int		    len;
3062     linenr_T	    lnum;
3063     long	    nchars;
3064     char_u	    *errmsg = NULL;
3065     int		    errmsg_allocated = FALSE;
3066     char_u	    *errnum = NULL;
3067     char_u	    *buffer;
3068     char_u	    smallbuf[SMBUFSIZE];
3069     char_u	    *backup_ext;
3070     int		    bufsize;
3071     long	    perm;		    /* file permissions */
3072     int		    retval = OK;
3073     int		    newfile = FALSE;	    /* TRUE if file doesn't exist yet */
3074     int		    msg_save = msg_scroll;
3075     int		    overwriting;	    /* TRUE if writing over original */
3076     int		    no_eol = FALSE;	    /* no end-of-line written */
3077     int		    device = FALSE;	    /* writing to a device */
3078     stat_T	    st_old;
3079     int		    prev_got_int = got_int;
3080     int		    checking_conversion;
3081     int		    file_readonly = FALSE;  /* overwritten file is read-only */
3082     static char	    *err_readonly = "is read-only (cannot override: \"W\" in 'cpoptions')";
3083 #if defined(UNIX)			    /*XXX fix me sometime? */
3084     int		    made_writable = FALSE;  /* 'w' bit has been set */
3085 #endif
3086 					/* writing everything */
3087     int		    whole = (start == 1 && end == buf->b_ml.ml_line_count);
3088     linenr_T	    old_line_count = buf->b_ml.ml_line_count;
3089     int		    attr;
3090     int		    fileformat;
3091     int		    write_bin;
3092     struct bw_info  write_info;		/* info for buf_write_bytes() */
3093     int		    converted = FALSE;
3094     int		    notconverted = FALSE;
3095     char_u	    *fenc;		/* effective 'fileencoding' */
3096     char_u	    *fenc_tofree = NULL; /* allocated "fenc" */
3097 #ifdef HAS_BW_FLAGS
3098     int		    wb_flags = 0;
3099 #endif
3100 #ifdef HAVE_ACL
3101     vim_acl_T	    acl = NULL;		/* ACL copied from original file to
3102 					   backup or new file */
3103 #endif
3104 #ifdef FEAT_PERSISTENT_UNDO
3105     int		    write_undo_file = FALSE;
3106     context_sha256_T sha_ctx;
3107 #endif
3108     unsigned int    bkc = get_bkc_value(buf);
3109 
3110     if (fname == NULL || *fname == NUL)	/* safety check */
3111 	return FAIL;
3112     if (buf->b_ml.ml_mfp == NULL)
3113     {
3114 	/* This can happen during startup when there is a stray "w" in the
3115 	 * vimrc file. */
3116 	emsg(_(e_emptybuf));
3117 	return FAIL;
3118     }
3119 
3120     /*
3121      * Disallow writing from .exrc and .vimrc in current directory for
3122      * security reasons.
3123      */
3124     if (check_secure())
3125 	return FAIL;
3126 
3127     /* Avoid a crash for a long name. */
3128     if (STRLEN(fname) >= MAXPATHL)
3129     {
3130 	emsg(_(e_longname));
3131 	return FAIL;
3132     }
3133 
3134     /* must init bw_conv_buf and bw_iconv_fd before jumping to "fail" */
3135     write_info.bw_conv_buf = NULL;
3136     write_info.bw_conv_error = FALSE;
3137     write_info.bw_conv_error_lnum = 0;
3138     write_info.bw_restlen = 0;
3139 #ifdef USE_ICONV
3140     write_info.bw_iconv_fd = (iconv_t)-1;
3141 #endif
3142 #ifdef FEAT_CRYPT
3143     write_info.bw_buffer = buf;
3144 #endif
3145 
3146     /* After writing a file changedtick changes but we don't want to display
3147      * the line. */
3148     ex_no_reprint = TRUE;
3149 
3150     /*
3151      * If there is no file name yet, use the one for the written file.
3152      * BF_NOTEDITED is set to reflect this (in case the write fails).
3153      * Don't do this when the write is for a filter command.
3154      * Don't do this when appending.
3155      * Only do this when 'cpoptions' contains the 'F' flag.
3156      */
3157     if (buf->b_ffname == NULL
3158 	    && reset_changed
3159 	    && whole
3160 	    && buf == curbuf
3161 #ifdef FEAT_QUICKFIX
3162 	    && !bt_nofile(buf)
3163 #endif
3164 	    && !filtering
3165 	    && (!append || vim_strchr(p_cpo, CPO_FNAMEAPP) != NULL)
3166 	    && vim_strchr(p_cpo, CPO_FNAMEW) != NULL)
3167     {
3168 	if (set_rw_fname(fname, sfname) == FAIL)
3169 	    return FAIL;
3170 	buf = curbuf;	    /* just in case autocmds made "buf" invalid */
3171     }
3172 
3173     if (sfname == NULL)
3174 	sfname = fname;
3175     /*
3176      * For Unix: Use the short file name whenever possible.
3177      * Avoids problems with networks and when directory names are changed.
3178      * Don't do this for MS-DOS, a "cd" in a sub-shell may have moved us to
3179      * another directory, which we don't detect
3180      */
3181     ffname = fname;			    /* remember full fname */
3182 #ifdef UNIX
3183     fname = sfname;
3184 #endif
3185 
3186     if (buf->b_ffname != NULL && fnamecmp(ffname, buf->b_ffname) == 0)
3187 	overwriting = TRUE;
3188     else
3189 	overwriting = FALSE;
3190 
3191     if (exiting)
3192 	settmode(TMODE_COOK);	    /* when exiting allow typeahead now */
3193 
3194     ++no_wait_return;		    /* don't wait for return yet */
3195 
3196     /*
3197      * Set '[ and '] marks to the lines to be written.
3198      */
3199     buf->b_op_start.lnum = start;
3200     buf->b_op_start.col = 0;
3201     buf->b_op_end.lnum = end;
3202     buf->b_op_end.col = 0;
3203 
3204     {
3205 	aco_save_T	aco;
3206 	int		buf_ffname = FALSE;
3207 	int		buf_sfname = FALSE;
3208 	int		buf_fname_f = FALSE;
3209 	int		buf_fname_s = FALSE;
3210 	int		did_cmd = FALSE;
3211 	int		nofile_err = FALSE;
3212 	int		empty_memline = (buf->b_ml.ml_mfp == NULL);
3213 	bufref_T	bufref;
3214 
3215 	/*
3216 	 * Apply PRE autocommands.
3217 	 * Set curbuf to the buffer to be written.
3218 	 * Careful: The autocommands may call buf_write() recursively!
3219 	 */
3220 	if (ffname == buf->b_ffname)
3221 	    buf_ffname = TRUE;
3222 	if (sfname == buf->b_sfname)
3223 	    buf_sfname = TRUE;
3224 	if (fname == buf->b_ffname)
3225 	    buf_fname_f = TRUE;
3226 	if (fname == buf->b_sfname)
3227 	    buf_fname_s = TRUE;
3228 
3229 	/* set curwin/curbuf to buf and save a few things */
3230 	aucmd_prepbuf(&aco, buf);
3231 	set_bufref(&bufref, buf);
3232 
3233 	if (append)
3234 	{
3235 	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEAPPENDCMD,
3236 					 sfname, sfname, FALSE, curbuf, eap)))
3237 	    {
3238 #ifdef FEAT_QUICKFIX
3239 		if (overwriting && bt_nofile(curbuf))
3240 		    nofile_err = TRUE;
3241 		else
3242 #endif
3243 		    apply_autocmds_exarg(EVENT_FILEAPPENDPRE,
3244 					  sfname, sfname, FALSE, curbuf, eap);
3245 	    }
3246 	}
3247 	else if (filtering)
3248 	{
3249 	    apply_autocmds_exarg(EVENT_FILTERWRITEPRE,
3250 					    NULL, sfname, FALSE, curbuf, eap);
3251 	}
3252 	else if (reset_changed && whole)
3253 	{
3254 	    int was_changed = curbufIsChanged();
3255 
3256 	    did_cmd = apply_autocmds_exarg(EVENT_BUFWRITECMD,
3257 					  sfname, sfname, FALSE, curbuf, eap);
3258 	    if (did_cmd)
3259 	    {
3260 		if (was_changed && !curbufIsChanged())
3261 		{
3262 		    /* Written everything correctly and BufWriteCmd has reset
3263 		     * 'modified': Correct the undo information so that an
3264 		     * undo now sets 'modified'. */
3265 		    u_unchanged(curbuf);
3266 		    u_update_save_nr(curbuf);
3267 		}
3268 	    }
3269 	    else
3270 	    {
3271 #ifdef FEAT_QUICKFIX
3272 		if (overwriting && bt_nofile(curbuf))
3273 		    nofile_err = TRUE;
3274 		else
3275 #endif
3276 		    apply_autocmds_exarg(EVENT_BUFWRITEPRE,
3277 					  sfname, sfname, FALSE, curbuf, eap);
3278 	    }
3279 	}
3280 	else
3281 	{
3282 	    if (!(did_cmd = apply_autocmds_exarg(EVENT_FILEWRITECMD,
3283 					 sfname, sfname, FALSE, curbuf, eap)))
3284 	    {
3285 #ifdef FEAT_QUICKFIX
3286 		if (overwriting && bt_nofile(curbuf))
3287 		    nofile_err = TRUE;
3288 		else
3289 #endif
3290 		    apply_autocmds_exarg(EVENT_FILEWRITEPRE,
3291 					  sfname, sfname, FALSE, curbuf, eap);
3292 	    }
3293 	}
3294 
3295 	/* restore curwin/curbuf and a few other things */
3296 	aucmd_restbuf(&aco);
3297 
3298 	/*
3299 	 * In three situations we return here and don't write the file:
3300 	 * 1. the autocommands deleted or unloaded the buffer.
3301 	 * 2. The autocommands abort script processing.
3302 	 * 3. If one of the "Cmd" autocommands was executed.
3303 	 */
3304 	if (!bufref_valid(&bufref))
3305 	    buf = NULL;
3306 	if (buf == NULL || (buf->b_ml.ml_mfp == NULL && !empty_memline)
3307 				       || did_cmd || nofile_err
3308 #ifdef FEAT_EVAL
3309 				       || aborting()
3310 #endif
3311 				       )
3312 	{
3313 	    --no_wait_return;
3314 	    msg_scroll = msg_save;
3315 	    if (nofile_err)
3316 		emsg(_("E676: No matching autocommands for acwrite buffer"));
3317 
3318 	    if (nofile_err
3319 #ifdef FEAT_EVAL
3320 		    || aborting()
3321 #endif
3322 		    )
3323 		/* An aborting error, interrupt or exception in the
3324 		 * autocommands. */
3325 		return FAIL;
3326 	    if (did_cmd)
3327 	    {
3328 		if (buf == NULL)
3329 		    /* The buffer was deleted.  We assume it was written
3330 		     * (can't retry anyway). */
3331 		    return OK;
3332 		if (overwriting)
3333 		{
3334 		    /* Assume the buffer was written, update the timestamp. */
3335 		    ml_timestamp(buf);
3336 		    if (append)
3337 			buf->b_flags &= ~BF_NEW;
3338 		    else
3339 			buf->b_flags &= ~BF_WRITE_MASK;
3340 		}
3341 		if (reset_changed && buf->b_changed && !append
3342 			&& (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL))
3343 		    /* Buffer still changed, the autocommands didn't work
3344 		     * properly. */
3345 		    return FAIL;
3346 		return OK;
3347 	    }
3348 #ifdef FEAT_EVAL
3349 	    if (!aborting())
3350 #endif
3351 		emsg(_("E203: Autocommands deleted or unloaded buffer to be written"));
3352 	    return FAIL;
3353 	}
3354 
3355 	/*
3356 	 * The autocommands may have changed the number of lines in the file.
3357 	 * When writing the whole file, adjust the end.
3358 	 * When writing part of the file, assume that the autocommands only
3359 	 * changed the number of lines that are to be written (tricky!).
3360 	 */
3361 	if (buf->b_ml.ml_line_count != old_line_count)
3362 	{
3363 	    if (whole)						/* write all */
3364 		end = buf->b_ml.ml_line_count;
3365 	    else if (buf->b_ml.ml_line_count > old_line_count)	/* more lines */
3366 		end += buf->b_ml.ml_line_count - old_line_count;
3367 	    else						/* less lines */
3368 	    {
3369 		end -= old_line_count - buf->b_ml.ml_line_count;
3370 		if (end < start)
3371 		{
3372 		    --no_wait_return;
3373 		    msg_scroll = msg_save;
3374 		    emsg(_("E204: Autocommand changed number of lines in unexpected way"));
3375 		    return FAIL;
3376 		}
3377 	    }
3378 	}
3379 
3380 	/*
3381 	 * The autocommands may have changed the name of the buffer, which may
3382 	 * be kept in fname, ffname and sfname.
3383 	 */
3384 	if (buf_ffname)
3385 	    ffname = buf->b_ffname;
3386 	if (buf_sfname)
3387 	    sfname = buf->b_sfname;
3388 	if (buf_fname_f)
3389 	    fname = buf->b_ffname;
3390 	if (buf_fname_s)
3391 	    fname = buf->b_sfname;
3392     }
3393 
3394 #ifdef FEAT_NETBEANS_INTG
3395     if (netbeans_active() && isNetbeansBuffer(buf))
3396     {
3397 	if (whole)
3398 	{
3399 	    /*
3400 	     * b_changed can be 0 after an undo, but we still need to write
3401 	     * the buffer to NetBeans.
3402 	     */
3403 	    if (buf->b_changed || isNetbeansModified(buf))
3404 	    {
3405 		--no_wait_return;		/* may wait for return now */
3406 		msg_scroll = msg_save;
3407 		netbeans_save_buffer(buf);	/* no error checking... */
3408 		return retval;
3409 	    }
3410 	    else
3411 	    {
3412 		errnum = (char_u *)"E656: ";
3413 		errmsg = (char_u *)_("NetBeans disallows writes of unmodified buffers");
3414 		buffer = NULL;
3415 		goto fail;
3416 	    }
3417 	}
3418 	else
3419 	{
3420 	    errnum = (char_u *)"E657: ";
3421 	    errmsg = (char_u *)_("Partial writes disallowed for NetBeans buffers");
3422 	    buffer = NULL;
3423 	    goto fail;
3424 	}
3425     }
3426 #endif
3427 
3428     if (shortmess(SHM_OVER) && !exiting)
3429 	msg_scroll = FALSE;	    /* overwrite previous file message */
3430     else
3431 	msg_scroll = TRUE;	    /* don't overwrite previous file message */
3432     if (!filtering)
3433 	filemess(buf,
3434 #ifndef UNIX
3435 		sfname,
3436 #else
3437 		fname,
3438 #endif
3439 		    (char_u *)"", 0);	/* show that we are busy */
3440     msg_scroll = FALSE;		    /* always overwrite the file message now */
3441 
3442     buffer = alloc(BUFSIZE);
3443     if (buffer == NULL)		    /* can't allocate big buffer, use small
3444 				     * one (to be able to write when out of
3445 				     * memory) */
3446     {
3447 	buffer = smallbuf;
3448 	bufsize = SMBUFSIZE;
3449     }
3450     else
3451 	bufsize = BUFSIZE;
3452 
3453     /*
3454      * Get information about original file (if there is one).
3455      */
3456 #if defined(UNIX)
3457     st_old.st_dev = 0;
3458     st_old.st_ino = 0;
3459     perm = -1;
3460     if (mch_stat((char *)fname, &st_old) < 0)
3461 	newfile = TRUE;
3462     else
3463     {
3464 	perm = st_old.st_mode;
3465 	if (!S_ISREG(st_old.st_mode))		/* not a file */
3466 	{
3467 	    if (S_ISDIR(st_old.st_mode))
3468 	    {
3469 		errnum = (char_u *)"E502: ";
3470 		errmsg = (char_u *)_("is a directory");
3471 		goto fail;
3472 	    }
3473 	    if (mch_nodetype(fname) != NODE_WRITABLE)
3474 	    {
3475 		errnum = (char_u *)"E503: ";
3476 		errmsg = (char_u *)_("is not a file or writable device");
3477 		goto fail;
3478 	    }
3479 	    /* It's a device of some kind (or a fifo) which we can write to
3480 	     * but for which we can't make a backup. */
3481 	    device = TRUE;
3482 	    newfile = TRUE;
3483 	    perm = -1;
3484 	}
3485     }
3486 #else /* !UNIX */
3487     /*
3488      * Check for a writable device name.
3489      */
3490     c = mch_nodetype(fname);
3491     if (c == NODE_OTHER)
3492     {
3493 	errnum = (char_u *)"E503: ";
3494 	errmsg = (char_u *)_("is not a file or writable device");
3495 	goto fail;
3496     }
3497     if (c == NODE_WRITABLE)
3498     {
3499 # if defined(MSWIN)
3500 	/* MS-Windows allows opening a device, but we will probably get stuck
3501 	 * trying to write to it.  */
3502 	if (!p_odev)
3503 	{
3504 	    errnum = (char_u *)"E796: ";
3505 	    errmsg = (char_u *)_("writing to device disabled with 'opendevice' option");
3506 	    goto fail;
3507 	}
3508 # endif
3509 	device = TRUE;
3510 	newfile = TRUE;
3511 	perm = -1;
3512     }
3513     else
3514     {
3515 	perm = mch_getperm(fname);
3516 	if (perm < 0)
3517 	    newfile = TRUE;
3518 	else if (mch_isdir(fname))
3519 	{
3520 	    errnum = (char_u *)"E502: ";
3521 	    errmsg = (char_u *)_("is a directory");
3522 	    goto fail;
3523 	}
3524 	if (overwriting)
3525 	    (void)mch_stat((char *)fname, &st_old);
3526     }
3527 #endif /* !UNIX */
3528 
3529     if (!device && !newfile)
3530     {
3531 	/*
3532 	 * Check if the file is really writable (when renaming the file to
3533 	 * make a backup we won't discover it later).
3534 	 */
3535 	file_readonly = check_file_readonly(fname, (int)perm);
3536 
3537 	if (!forceit && file_readonly)
3538 	{
3539 	    if (vim_strchr(p_cpo, CPO_FWRITE) != NULL)
3540 	    {
3541 		errnum = (char_u *)"E504: ";
3542 		errmsg = (char_u *)_(err_readonly);
3543 	    }
3544 	    else
3545 	    {
3546 		errnum = (char_u *)"E505: ";
3547 		errmsg = (char_u *)_("is read-only (add ! to override)");
3548 	    }
3549 	    goto fail;
3550 	}
3551 
3552 	/*
3553 	 * Check if the timestamp hasn't changed since reading the file.
3554 	 */
3555 	if (overwriting)
3556 	{
3557 	    retval = check_mtime(buf, &st_old);
3558 	    if (retval == FAIL)
3559 		goto fail;
3560 	}
3561     }
3562 
3563 #ifdef HAVE_ACL
3564     /*
3565      * For systems that support ACL: get the ACL from the original file.
3566      */
3567     if (!newfile)
3568 	acl = mch_get_acl(fname);
3569 #endif
3570 
3571     /*
3572      * If 'backupskip' is not empty, don't make a backup for some files.
3573      */
3574     dobackup = (p_wb || p_bk || *p_pm != NUL);
3575 #ifdef FEAT_WILDIGN
3576     if (dobackup && *p_bsk != NUL && match_file_list(p_bsk, sfname, ffname))
3577 	dobackup = FALSE;
3578 #endif
3579 
3580     /*
3581      * Save the value of got_int and reset it.  We don't want a previous
3582      * interruption cancel writing, only hitting CTRL-C while writing should
3583      * abort it.
3584      */
3585     prev_got_int = got_int;
3586     got_int = FALSE;
3587 
3588     /* Mark the buffer as 'being saved' to prevent changed buffer warnings */
3589     buf->b_saving = TRUE;
3590 
3591     /*
3592      * If we are not appending or filtering, the file exists, and the
3593      * 'writebackup', 'backup' or 'patchmode' option is set, need a backup.
3594      * When 'patchmode' is set also make a backup when appending.
3595      *
3596      * Do not make any backup, if 'writebackup' and 'backup' are both switched
3597      * off.  This helps when editing large files on almost-full disks.
3598      */
3599     if (!(append && *p_pm == NUL) && !filtering && perm >= 0 && dobackup)
3600     {
3601 #if defined(UNIX) || defined(MSWIN)
3602 	stat_T	    st;
3603 #endif
3604 
3605 	if ((bkc & BKC_YES) || append)	/* "yes" */
3606 	    backup_copy = TRUE;
3607 #if defined(UNIX) || defined(MSWIN)
3608 	else if ((bkc & BKC_AUTO))	/* "auto" */
3609 	{
3610 	    int		i;
3611 
3612 # ifdef UNIX
3613 	    /*
3614 	     * Don't rename the file when:
3615 	     * - it's a hard link
3616 	     * - it's a symbolic link
3617 	     * - we don't have write permission in the directory
3618 	     * - we can't set the owner/group of the new file
3619 	     */
3620 	    if (st_old.st_nlink > 1
3621 		    || mch_lstat((char *)fname, &st) < 0
3622 		    || st.st_dev != st_old.st_dev
3623 		    || st.st_ino != st_old.st_ino
3624 #  ifndef HAVE_FCHOWN
3625 		    || st.st_uid != st_old.st_uid
3626 		    || st.st_gid != st_old.st_gid
3627 #  endif
3628 		    )
3629 		backup_copy = TRUE;
3630 	    else
3631 # else
3632 #  ifdef MSWIN
3633 	    /* On NTFS file systems hard links are possible. */
3634 	    if (mch_is_linked(fname))
3635 		backup_copy = TRUE;
3636 	    else
3637 #  endif
3638 # endif
3639 	    {
3640 		/*
3641 		 * Check if we can create a file and set the owner/group to
3642 		 * the ones from the original file.
3643 		 * First find a file name that doesn't exist yet (use some
3644 		 * arbitrary numbers).
3645 		 */
3646 		STRCPY(IObuff, fname);
3647 		for (i = 4913; ; i += 123)
3648 		{
3649 		    sprintf((char *)gettail(IObuff), "%d", i);
3650 		    if (mch_lstat((char *)IObuff, &st) < 0)
3651 			break;
3652 		}
3653 		fd = mch_open((char *)IObuff,
3654 				    O_CREAT|O_WRONLY|O_EXCL|O_NOFOLLOW, perm);
3655 		if (fd < 0)	/* can't write in directory */
3656 		    backup_copy = TRUE;
3657 		else
3658 		{
3659 # ifdef UNIX
3660 #  ifdef HAVE_FCHOWN
3661 		    vim_ignored = fchown(fd, st_old.st_uid, st_old.st_gid);
3662 #  endif
3663 		    if (mch_stat((char *)IObuff, &st) < 0
3664 			    || st.st_uid != st_old.st_uid
3665 			    || st.st_gid != st_old.st_gid
3666 			    || (long)st.st_mode != perm)
3667 			backup_copy = TRUE;
3668 # endif
3669 		    /* Close the file before removing it, on MS-Windows we
3670 		     * can't delete an open file. */
3671 		    close(fd);
3672 		    mch_remove(IObuff);
3673 # ifdef MSWIN
3674 		    /* MS-Windows may trigger a virus scanner to open the
3675 		     * file, we can't delete it then.  Keep trying for half a
3676 		     * second. */
3677 		    {
3678 			int try;
3679 
3680 			for (try = 0; try < 10; ++try)
3681 			{
3682 			    if (mch_lstat((char *)IObuff, &st) < 0)
3683 				break;
3684 			    ui_delay(50L, TRUE);  /* wait 50 msec */
3685 			    mch_remove(IObuff);
3686 			}
3687 		    }
3688 # endif
3689 		}
3690 	    }
3691 	}
3692 
3693 	/*
3694 	 * Break symlinks and/or hardlinks if we've been asked to.
3695 	 */
3696 	if ((bkc & BKC_BREAKSYMLINK) || (bkc & BKC_BREAKHARDLINK))
3697 	{
3698 # ifdef UNIX
3699 	    int	lstat_res;
3700 
3701 	    lstat_res = mch_lstat((char *)fname, &st);
3702 
3703 	    /* Symlinks. */
3704 	    if ((bkc & BKC_BREAKSYMLINK)
3705 		    && lstat_res == 0
3706 		    && st.st_ino != st_old.st_ino)
3707 		backup_copy = FALSE;
3708 
3709 	    /* Hardlinks. */
3710 	    if ((bkc & BKC_BREAKHARDLINK)
3711 		    && st_old.st_nlink > 1
3712 		    && (lstat_res != 0 || st.st_ino == st_old.st_ino))
3713 		backup_copy = FALSE;
3714 # else
3715 #  if defined(MSWIN)
3716 	    /* Symlinks. */
3717 	    if ((bkc & BKC_BREAKSYMLINK) && mch_is_symbolic_link(fname))
3718 		backup_copy = FALSE;
3719 
3720 	    /* Hardlinks. */
3721 	    if ((bkc & BKC_BREAKHARDLINK) && mch_is_hard_link(fname))
3722 		backup_copy = FALSE;
3723 #  endif
3724 # endif
3725 	}
3726 
3727 #endif
3728 
3729 	/* make sure we have a valid backup extension to use */
3730 	if (*p_bex == NUL)
3731 	    backup_ext = (char_u *)".bak";
3732 	else
3733 	    backup_ext = p_bex;
3734 
3735 	if (backup_copy
3736 		&& (fd = mch_open((char *)fname, O_RDONLY | O_EXTRA, 0)) >= 0)
3737 	{
3738 	    int		bfd;
3739 	    char_u	*copybuf, *wp;
3740 	    int		some_error = FALSE;
3741 	    stat_T	st_new;
3742 	    char_u	*dirp;
3743 	    char_u	*rootname;
3744 #if defined(UNIX) || defined(MSWIN)
3745 	    char_u      *p;
3746 #endif
3747 #if defined(UNIX)
3748 	    int		did_set_shortname;
3749 	    mode_t	umask_save;
3750 #endif
3751 
3752 	    copybuf = alloc(BUFSIZE + 1);
3753 	    if (copybuf == NULL)
3754 	    {
3755 		some_error = TRUE;	    /* out of memory */
3756 		goto nobackup;
3757 	    }
3758 
3759 	    /*
3760 	     * Try to make the backup in each directory in the 'bdir' option.
3761 	     *
3762 	     * Unix semantics has it, that we may have a writable file,
3763 	     * that cannot be recreated with a simple open(..., O_CREAT, ) e.g:
3764 	     *  - the directory is not writable,
3765 	     *  - the file may be a symbolic link,
3766 	     *  - the file may belong to another user/group, etc.
3767 	     *
3768 	     * For these reasons, the existing writable file must be truncated
3769 	     * and reused. Creation of a backup COPY will be attempted.
3770 	     */
3771 	    dirp = p_bdir;
3772 	    while (*dirp)
3773 	    {
3774 #ifdef UNIX
3775 		st_new.st_ino = 0;
3776 		st_new.st_dev = 0;
3777 		st_new.st_gid = 0;
3778 #endif
3779 
3780 		/*
3781 		 * Isolate one directory name, using an entry in 'bdir'.
3782 		 */
3783 		(void)copy_option_part(&dirp, copybuf, BUFSIZE, ",");
3784 
3785 #if defined(UNIX) || defined(MSWIN)
3786 		p = copybuf + STRLEN(copybuf);
3787 		if (after_pathsep(copybuf, p) && p[-1] == p[-2])
3788 		    // Ends with '//', use full path
3789 		    if ((p = make_percent_swname(copybuf, fname)) != NULL)
3790 		    {
3791 			backup = modname(p, backup_ext, FALSE);
3792 			vim_free(p);
3793 		    }
3794 #endif
3795 		rootname = get_file_in_dir(fname, copybuf);
3796 		if (rootname == NULL)
3797 		{
3798 		    some_error = TRUE;	    /* out of memory */
3799 		    goto nobackup;
3800 		}
3801 
3802 #if defined(UNIX)
3803 		did_set_shortname = FALSE;
3804 #endif
3805 
3806 		/*
3807 		 * May try twice if 'shortname' not set.
3808 		 */
3809 		for (;;)
3810 		{
3811 		    /*
3812 		     * Make the backup file name.
3813 		     */
3814 		    if (backup == NULL)
3815 			backup = buf_modname((buf->b_p_sn || buf->b_shortname),
3816 						 rootname, backup_ext, FALSE);
3817 		    if (backup == NULL)
3818 		    {
3819 			vim_free(rootname);
3820 			some_error = TRUE;		/* out of memory */
3821 			goto nobackup;
3822 		    }
3823 
3824 		    /*
3825 		     * Check if backup file already exists.
3826 		     */
3827 		    if (mch_stat((char *)backup, &st_new) >= 0)
3828 		    {
3829 #ifdef UNIX
3830 			/*
3831 			 * Check if backup file is same as original file.
3832 			 * May happen when modname() gave the same file back.
3833 			 * E.g. silly link, or file name-length reached.
3834 			 * If we don't check here, we either ruin the file
3835 			 * when copying or erase it after writing. jw.
3836 			 */
3837 			if (st_new.st_dev == st_old.st_dev
3838 					    && st_new.st_ino == st_old.st_ino)
3839 			{
3840 			    VIM_CLEAR(backup);	/* no backup file to delete */
3841 			    /*
3842 			     * may try again with 'shortname' set
3843 			     */
3844 			    if (!(buf->b_shortname || buf->b_p_sn))
3845 			    {
3846 				buf->b_shortname = TRUE;
3847 				did_set_shortname = TRUE;
3848 				continue;
3849 			    }
3850 				/* setting shortname didn't help */
3851 			    if (did_set_shortname)
3852 				buf->b_shortname = FALSE;
3853 			    break;
3854 			}
3855 #endif
3856 
3857 			/*
3858 			 * If we are not going to keep the backup file, don't
3859 			 * delete an existing one, try to use another name.
3860 			 * Change one character, just before the extension.
3861 			 */
3862 			if (!p_bk)
3863 			{
3864 			    wp = backup + STRLEN(backup) - 1
3865 							 - STRLEN(backup_ext);
3866 			    if (wp < backup)	/* empty file name ??? */
3867 				wp = backup;
3868 			    *wp = 'z';
3869 			    while (*wp > 'a'
3870 				    && mch_stat((char *)backup, &st_new) >= 0)
3871 				--*wp;
3872 			    /* They all exist??? Must be something wrong. */
3873 			    if (*wp == 'a')
3874 				VIM_CLEAR(backup);
3875 			}
3876 		    }
3877 		    break;
3878 		}
3879 		vim_free(rootname);
3880 
3881 		/*
3882 		 * Try to create the backup file
3883 		 */
3884 		if (backup != NULL)
3885 		{
3886 		    /* remove old backup, if present */
3887 		    mch_remove(backup);
3888 		    /* Open with O_EXCL to avoid the file being created while
3889 		     * we were sleeping (symlink hacker attack?). Reset umask
3890 		     * if possible to avoid mch_setperm() below. */
3891 #ifdef UNIX
3892 		    umask_save = umask(0);
3893 #endif
3894 		    bfd = mch_open((char *)backup,
3895 				O_WRONLY|O_CREAT|O_EXTRA|O_EXCL|O_NOFOLLOW,
3896 								 perm & 0777);
3897 #ifdef UNIX
3898 		    (void)umask(umask_save);
3899 #endif
3900 		    if (bfd < 0)
3901 			VIM_CLEAR(backup);
3902 		    else
3903 		    {
3904 			/* Set file protection same as original file, but
3905 			 * strip s-bit.  Only needed if umask() wasn't used
3906 			 * above. */
3907 #ifndef UNIX
3908 			(void)mch_setperm(backup, perm & 0777);
3909 #else
3910 			/*
3911 			 * Try to set the group of the backup same as the
3912 			 * original file. If this fails, set the protection
3913 			 * bits for the group same as the protection bits for
3914 			 * others.
3915 			 */
3916 			if (st_new.st_gid != st_old.st_gid
3917 # ifdef HAVE_FCHOWN  /* sequent-ptx lacks fchown() */
3918 				&& fchown(bfd, (uid_t)-1, st_old.st_gid) != 0
3919 # endif
3920 						)
3921 			    mch_setperm(backup,
3922 					  (perm & 0707) | ((perm & 07) << 3));
3923 # if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
3924 			mch_copy_sec(fname, backup);
3925 # endif
3926 #endif
3927 
3928 			/*
3929 			 * copy the file.
3930 			 */
3931 			write_info.bw_fd = bfd;
3932 			write_info.bw_buf = copybuf;
3933 #ifdef HAS_BW_FLAGS
3934 			write_info.bw_flags = FIO_NOCONVERT;
3935 #endif
3936 			while ((write_info.bw_len = read_eintr(fd, copybuf,
3937 								BUFSIZE)) > 0)
3938 			{
3939 			    if (buf_write_bytes(&write_info) == FAIL)
3940 			    {
3941 				errmsg = (char_u *)_("E506: Can't write to backup file (add ! to override)");
3942 				break;
3943 			    }
3944 			    ui_breakcheck();
3945 			    if (got_int)
3946 			    {
3947 				errmsg = (char_u *)_(e_interr);
3948 				break;
3949 			    }
3950 			}
3951 
3952 			if (close(bfd) < 0 && errmsg == NULL)
3953 			    errmsg = (char_u *)_("E507: Close error for backup file (add ! to override)");
3954 			if (write_info.bw_len < 0)
3955 			    errmsg = (char_u *)_("E508: Can't read file for backup (add ! to override)");
3956 #ifdef UNIX
3957 			set_file_time(backup, st_old.st_atime, st_old.st_mtime);
3958 #endif
3959 #ifdef HAVE_ACL
3960 			mch_set_acl(backup, acl);
3961 #endif
3962 #if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
3963 			mch_copy_sec(fname, backup);
3964 #endif
3965 			break;
3966 		    }
3967 		}
3968 	    }
3969     nobackup:
3970 	    close(fd);		/* ignore errors for closing read file */
3971 	    vim_free(copybuf);
3972 
3973 	    if (backup == NULL && errmsg == NULL)
3974 		errmsg = (char_u *)_("E509: Cannot create backup file (add ! to override)");
3975 	    /* ignore errors when forceit is TRUE */
3976 	    if ((some_error || errmsg != NULL) && !forceit)
3977 	    {
3978 		retval = FAIL;
3979 		goto fail;
3980 	    }
3981 	    errmsg = NULL;
3982 	}
3983 	else
3984 	{
3985 	    char_u	*dirp;
3986 	    char_u	*p;
3987 	    char_u	*rootname;
3988 
3989 	    /*
3990 	     * Make a backup by renaming the original file.
3991 	     */
3992 	    /*
3993 	     * If 'cpoptions' includes the "W" flag, we don't want to
3994 	     * overwrite a read-only file.  But rename may be possible
3995 	     * anyway, thus we need an extra check here.
3996 	     */
3997 	    if (file_readonly && vim_strchr(p_cpo, CPO_FWRITE) != NULL)
3998 	    {
3999 		errnum = (char_u *)"E504: ";
4000 		errmsg = (char_u *)_(err_readonly);
4001 		goto fail;
4002 	    }
4003 
4004 	    /*
4005 	     *
4006 	     * Form the backup file name - change path/fo.o.h to
4007 	     * path/fo.o.h.bak Try all directories in 'backupdir', first one
4008 	     * that works is used.
4009 	     */
4010 	    dirp = p_bdir;
4011 	    while (*dirp)
4012 	    {
4013 		/*
4014 		 * Isolate one directory name and make the backup file name.
4015 		 */
4016 		(void)copy_option_part(&dirp, IObuff, IOSIZE, ",");
4017 
4018 #if defined(UNIX) || defined(MSWIN)
4019 		p = IObuff + STRLEN(IObuff);
4020 		if (after_pathsep(IObuff, p) && p[-1] == p[-2])
4021 		    // path ends with '//', use full path
4022 		    if ((p = make_percent_swname(IObuff, fname)) != NULL)
4023 		    {
4024 			backup = modname(p, backup_ext, FALSE);
4025 			vim_free(p);
4026 		    }
4027 #endif
4028 		if (backup == NULL)
4029 		{
4030 		    rootname = get_file_in_dir(fname, IObuff);
4031 		    if (rootname == NULL)
4032 			backup = NULL;
4033 		    else
4034 		    {
4035 			backup = buf_modname(
4036 				(buf->b_p_sn || buf->b_shortname),
4037 						rootname, backup_ext, FALSE);
4038 			vim_free(rootname);
4039 		    }
4040 		}
4041 
4042 		if (backup != NULL)
4043 		{
4044 		    /*
4045 		     * If we are not going to keep the backup file, don't
4046 		     * delete an existing one, try to use another name.
4047 		     * Change one character, just before the extension.
4048 		     */
4049 		    if (!p_bk && mch_getperm(backup) >= 0)
4050 		    {
4051 			p = backup + STRLEN(backup) - 1 - STRLEN(backup_ext);
4052 			if (p < backup)	/* empty file name ??? */
4053 			    p = backup;
4054 			*p = 'z';
4055 			while (*p > 'a' && mch_getperm(backup) >= 0)
4056 			    --*p;
4057 			/* They all exist??? Must be something wrong! */
4058 			if (*p == 'a')
4059 			    VIM_CLEAR(backup);
4060 		    }
4061 		}
4062 		if (backup != NULL)
4063 		{
4064 		    /*
4065 		     * Delete any existing backup and move the current version
4066 		     * to the backup.	For safety, we don't remove the backup
4067 		     * until the write has finished successfully. And if the
4068 		     * 'backup' option is set, leave it around.
4069 		     */
4070 		    /*
4071 		     * If the renaming of the original file to the backup file
4072 		     * works, quit here.
4073 		     */
4074 		    if (vim_rename(fname, backup) == 0)
4075 			break;
4076 
4077 		    VIM_CLEAR(backup);   /* don't do the rename below */
4078 		}
4079 	    }
4080 	    if (backup == NULL && !forceit)
4081 	    {
4082 		errmsg = (char_u *)_("E510: Can't make backup file (add ! to override)");
4083 		goto fail;
4084 	    }
4085 	}
4086     }
4087 
4088 #if defined(UNIX)
4089     /* When using ":w!" and the file was read-only: make it writable */
4090     if (forceit && perm >= 0 && !(perm & 0200) && st_old.st_uid == getuid()
4091 				     && vim_strchr(p_cpo, CPO_FWRITE) == NULL)
4092     {
4093 	perm |= 0200;
4094 	(void)mch_setperm(fname, perm);
4095 	made_writable = TRUE;
4096     }
4097 #endif
4098 
4099     /* When using ":w!" and writing to the current file, 'readonly' makes no
4100      * sense, reset it, unless 'Z' appears in 'cpoptions'.  */
4101     if (forceit && overwriting && vim_strchr(p_cpo, CPO_KEEPRO) == NULL)
4102     {
4103 	buf->b_p_ro = FALSE;
4104 #ifdef FEAT_TITLE
4105 	need_maketitle = TRUE;	    /* set window title later */
4106 #endif
4107 	status_redraw_all();	    /* redraw status lines later */
4108     }
4109 
4110     if (end > buf->b_ml.ml_line_count)
4111 	end = buf->b_ml.ml_line_count;
4112     if (buf->b_ml.ml_flags & ML_EMPTY)
4113 	start = end + 1;
4114 
4115     /*
4116      * If the original file is being overwritten, there is a small chance that
4117      * we crash in the middle of writing. Therefore the file is preserved now.
4118      * This makes all block numbers positive so that recovery does not need
4119      * the original file.
4120      * Don't do this if there is a backup file and we are exiting.
4121      */
4122     if (reset_changed && !newfile && overwriting
4123 					      && !(exiting && backup != NULL))
4124     {
4125 	ml_preserve(buf, FALSE);
4126 	if (got_int)
4127 	{
4128 	    errmsg = (char_u *)_(e_interr);
4129 	    goto restore_backup;
4130 	}
4131     }
4132 
4133 #ifdef VMS
4134     vms_remove_version(fname); /* remove version */
4135 #endif
4136     /* Default: write the file directly.  May write to a temp file for
4137      * multi-byte conversion. */
4138     wfname = fname;
4139 
4140     /* Check for forced 'fileencoding' from "++opt=val" argument. */
4141     if (eap != NULL && eap->force_enc != 0)
4142     {
4143 	fenc = eap->cmd + eap->force_enc;
4144 	fenc = enc_canonize(fenc);
4145 	fenc_tofree = fenc;
4146     }
4147     else
4148 	fenc = buf->b_p_fenc;
4149 
4150     /*
4151      * Check if the file needs to be converted.
4152      */
4153     converted = need_conversion(fenc);
4154 
4155     /*
4156      * Check if UTF-8 to UCS-2/4 or Latin1 conversion needs to be done.  Or
4157      * Latin1 to Unicode conversion.  This is handled in buf_write_bytes().
4158      * Prepare the flags for it and allocate bw_conv_buf when needed.
4159      */
4160     if (converted && (enc_utf8 || STRCMP(p_enc, "latin1") == 0))
4161     {
4162 	wb_flags = get_fio_flags(fenc);
4163 	if (wb_flags & (FIO_UCS2 | FIO_UCS4 | FIO_UTF16 | FIO_UTF8))
4164 	{
4165 	    /* Need to allocate a buffer to translate into. */
4166 	    if (wb_flags & (FIO_UCS2 | FIO_UTF16 | FIO_UTF8))
4167 		write_info.bw_conv_buflen = bufsize * 2;
4168 	    else /* FIO_UCS4 */
4169 		write_info.bw_conv_buflen = bufsize * 4;
4170 	    write_info.bw_conv_buf
4171 			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
4172 	    if (write_info.bw_conv_buf == NULL)
4173 		end = 0;
4174 	}
4175     }
4176 
4177 #ifdef MSWIN
4178     if (converted && wb_flags == 0 && (wb_flags = get_win_fio_flags(fenc)) != 0)
4179     {
4180 	/* Convert UTF-8 -> UCS-2 and UCS-2 -> DBCS.  Worst-case * 4: */
4181 	write_info.bw_conv_buflen = bufsize * 4;
4182 	write_info.bw_conv_buf
4183 			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
4184 	if (write_info.bw_conv_buf == NULL)
4185 	    end = 0;
4186     }
4187 #endif
4188 
4189 #ifdef MACOS_CONVERT
4190     if (converted && wb_flags == 0 && (wb_flags = get_mac_fio_flags(fenc)) != 0)
4191     {
4192 	write_info.bw_conv_buflen = bufsize * 3;
4193 	write_info.bw_conv_buf
4194 			    = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
4195 	if (write_info.bw_conv_buf == NULL)
4196 	    end = 0;
4197     }
4198 #endif
4199 
4200 #if defined(FEAT_EVAL) || defined(USE_ICONV)
4201     if (converted && wb_flags == 0)
4202     {
4203 # ifdef USE_ICONV
4204 	/*
4205 	 * Use iconv() conversion when conversion is needed and it's not done
4206 	 * internally.
4207 	 */
4208 	write_info.bw_iconv_fd = (iconv_t)my_iconv_open(fenc,
4209 					enc_utf8 ? (char_u *)"utf-8" : p_enc);
4210 	if (write_info.bw_iconv_fd != (iconv_t)-1)
4211 	{
4212 	    /* We're going to use iconv(), allocate a buffer to convert in. */
4213 	    write_info.bw_conv_buflen = bufsize * ICONV_MULT;
4214 	    write_info.bw_conv_buf
4215 			   = lalloc((long_u)write_info.bw_conv_buflen, TRUE);
4216 	    if (write_info.bw_conv_buf == NULL)
4217 		end = 0;
4218 	    write_info.bw_first = TRUE;
4219 	}
4220 #  ifdef FEAT_EVAL
4221 	else
4222 #  endif
4223 # endif
4224 
4225 # ifdef FEAT_EVAL
4226 	    /*
4227 	     * When the file needs to be converted with 'charconvert' after
4228 	     * writing, write to a temp file instead and let the conversion
4229 	     * overwrite the original file.
4230 	     */
4231 	    if (*p_ccv != NUL)
4232 	    {
4233 		wfname = vim_tempname('w', FALSE);
4234 		if (wfname == NULL)	/* Can't write without a tempfile! */
4235 		{
4236 		    errmsg = (char_u *)_("E214: Can't find temp file for writing");
4237 		    goto restore_backup;
4238 		}
4239 	    }
4240 # endif
4241     }
4242 #endif
4243     if (converted && wb_flags == 0
4244 #ifdef USE_ICONV
4245 	    && write_info.bw_iconv_fd == (iconv_t)-1
4246 # endif
4247 # ifdef FEAT_EVAL
4248 	    && wfname == fname
4249 # endif
4250 	    )
4251     {
4252 	if (!forceit)
4253 	{
4254 	    errmsg = (char_u *)_("E213: Cannot convert (add ! to write without conversion)");
4255 	    goto restore_backup;
4256 	}
4257 	notconverted = TRUE;
4258     }
4259 
4260     /*
4261      * If conversion is taking place, we may first pretend to write and check
4262      * for conversion errors.  Then loop again to write for real.
4263      * When not doing conversion this writes for real right away.
4264      */
4265     for (checking_conversion = TRUE; ; checking_conversion = FALSE)
4266     {
4267 	/*
4268 	 * There is no need to check conversion when:
4269 	 * - there is no conversion
4270 	 * - we make a backup file, that can be restored in case of conversion
4271 	 *   failure.
4272 	 */
4273 	if (!converted || dobackup)
4274 	    checking_conversion = FALSE;
4275 
4276 	if (checking_conversion)
4277 	{
4278 	    /* Make sure we don't write anything. */
4279 	    fd = -1;
4280 	    write_info.bw_fd = fd;
4281 	}
4282 	else
4283 	{
4284 #ifdef HAVE_FTRUNCATE
4285 # define TRUNC_ON_OPEN 0
4286 #else
4287 # define TRUNC_ON_OPEN O_TRUNC
4288 #endif
4289 	    /*
4290 	     * Open the file "wfname" for writing.
4291 	     * We may try to open the file twice: If we can't write to the file
4292 	     * and forceit is TRUE we delete the existing file and try to
4293 	     * create a new one. If this still fails we may have lost the
4294 	     * original file!  (this may happen when the user reached his
4295 	     * quotum for number of files).
4296 	     * Appending will fail if the file does not exist and forceit is
4297 	     * FALSE.
4298 	     */
4299 	    while ((fd = mch_open((char *)wfname, O_WRONLY | O_EXTRA | (append
4300 				? (forceit ? (O_APPEND | O_CREAT) : O_APPEND)
4301 				: (O_CREAT | TRUNC_ON_OPEN))
4302 				, perm < 0 ? 0666 : (perm & 0777))) < 0)
4303 	    {
4304 		/*
4305 		 * A forced write will try to create a new file if the old one
4306 		 * is still readonly. This may also happen when the directory
4307 		 * is read-only. In that case the mch_remove() will fail.
4308 		 */
4309 		if (errmsg == NULL)
4310 		{
4311 #ifdef UNIX
4312 		    stat_T	st;
4313 
4314 		    /* Don't delete the file when it's a hard or symbolic link.
4315 		     */
4316 		    if ((!newfile && st_old.st_nlink > 1)
4317 			    || (mch_lstat((char *)fname, &st) == 0
4318 				&& (st.st_dev != st_old.st_dev
4319 				    || st.st_ino != st_old.st_ino)))
4320 			errmsg = (char_u *)_("E166: Can't open linked file for writing");
4321 		    else
4322 #endif
4323 		    {
4324 			errmsg = (char_u *)_("E212: Can't open file for writing");
4325 			if (forceit && vim_strchr(p_cpo, CPO_FWRITE) == NULL
4326 								  && perm >= 0)
4327 			{
4328 #ifdef UNIX
4329 			    /* we write to the file, thus it should be marked
4330 			       writable after all */
4331 			    if (!(perm & 0200))
4332 				made_writable = TRUE;
4333 			    perm |= 0200;
4334 			    if (st_old.st_uid != getuid()
4335 						  || st_old.st_gid != getgid())
4336 				perm &= 0777;
4337 #endif
4338 			    if (!append)  /* don't remove when appending */
4339 				mch_remove(wfname);
4340 			    continue;
4341 			}
4342 		    }
4343 		}
4344 
4345 restore_backup:
4346 		{
4347 		    stat_T	st;
4348 
4349 		    /*
4350 		     * If we failed to open the file, we don't need a backup.
4351 		     * Throw it away.  If we moved or removed the original file
4352 		     * try to put the backup in its place.
4353 		     */
4354 		    if (backup != NULL && wfname == fname)
4355 		    {
4356 			if (backup_copy)
4357 			{
4358 			    /*
4359 			     * There is a small chance that we removed the
4360 			     * original, try to move the copy in its place.
4361 			     * This may not work if the vim_rename() fails.
4362 			     * In that case we leave the copy around.
4363 			     */
4364 			    /* If file does not exist, put the copy in its
4365 			     * place */
4366 			    if (mch_stat((char *)fname, &st) < 0)
4367 				vim_rename(backup, fname);
4368 			    /* if original file does exist throw away the copy
4369 			     */
4370 			    if (mch_stat((char *)fname, &st) >= 0)
4371 				mch_remove(backup);
4372 			}
4373 			else
4374 			{
4375 			    /* try to put the original file back */
4376 			    vim_rename(backup, fname);
4377 			}
4378 		    }
4379 
4380 		    /* if original file no longer exists give an extra warning
4381 		     */
4382 		    if (!newfile && mch_stat((char *)fname, &st) < 0)
4383 			end = 0;
4384 		}
4385 
4386 		if (wfname != fname)
4387 		    vim_free(wfname);
4388 		goto fail;
4389 	    }
4390 	    write_info.bw_fd = fd;
4391 
4392 #if defined(UNIX)
4393 	    {
4394 		stat_T	st;
4395 
4396 		/* Double check we are writing the intended file before making
4397 		 * any changes. */
4398 		if (overwriting
4399 			&& (!dobackup || backup_copy)
4400 			&& fname == wfname
4401 			&& perm >= 0
4402 			&& mch_fstat(fd, &st) == 0
4403 			&& st.st_ino != st_old.st_ino)
4404 		{
4405 		    close(fd);
4406 		    errmsg = (char_u *)_("E949: File changed while writing");
4407 		    goto fail;
4408 		}
4409 	    }
4410 #endif
4411 #ifdef HAVE_FTRUNCATE
4412 	    if (!append)
4413 		vim_ignored = ftruncate(fd, (off_t)0);
4414 #endif
4415 
4416 #if defined(MSWIN)
4417 	    if (backup != NULL && overwriting && !append)
4418 	    {
4419 		if (backup_copy)
4420 		    (void)mch_copy_file_attribute(wfname, backup);
4421 		else
4422 		    (void)mch_copy_file_attribute(backup, wfname);
4423 	    }
4424 
4425 	    if (!overwriting && !append)
4426 	    {
4427 		if (buf->b_ffname != NULL)
4428 		    (void)mch_copy_file_attribute(buf->b_ffname, wfname);
4429 		/* Should copy resource fork */
4430 	    }
4431 #endif
4432 
4433 #ifdef FEAT_CRYPT
4434 	    if (*buf->b_p_key != NUL && !filtering)
4435 	    {
4436 		char_u		*header;
4437 		int		header_len;
4438 
4439 		buf->b_cryptstate = crypt_create_for_writing(
4440 						      crypt_get_method_nr(buf),
4441 					   buf->b_p_key, &header, &header_len);
4442 		if (buf->b_cryptstate == NULL || header == NULL)
4443 		    end = 0;
4444 		else
4445 		{
4446 		    /* Write magic number, so that Vim knows how this file is
4447 		     * encrypted when reading it back. */
4448 		    write_info.bw_buf = header;
4449 		    write_info.bw_len = header_len;
4450 		    write_info.bw_flags = FIO_NOCONVERT;
4451 		    if (buf_write_bytes(&write_info) == FAIL)
4452 			end = 0;
4453 		    wb_flags |= FIO_ENCRYPTED;
4454 		    vim_free(header);
4455 		}
4456 	    }
4457 #endif
4458 	}
4459 	errmsg = NULL;
4460 
4461 	write_info.bw_buf = buffer;
4462 	nchars = 0;
4463 
4464 	/* use "++bin", "++nobin" or 'binary' */
4465 	if (eap != NULL && eap->force_bin != 0)
4466 	    write_bin = (eap->force_bin == FORCE_BIN);
4467 	else
4468 	    write_bin = buf->b_p_bin;
4469 
4470 	/*
4471 	 * The BOM is written just after the encryption magic number.
4472 	 * Skip it when appending and the file already existed, the BOM only
4473 	 * makes sense at the start of the file.
4474 	 */
4475 	if (buf->b_p_bomb && !write_bin && (!append || perm < 0))
4476 	{
4477 	    write_info.bw_len = make_bom(buffer, fenc);
4478 	    if (write_info.bw_len > 0)
4479 	    {
4480 		/* don't convert, do encryption */
4481 		write_info.bw_flags = FIO_NOCONVERT | wb_flags;
4482 		if (buf_write_bytes(&write_info) == FAIL)
4483 		    end = 0;
4484 		else
4485 		    nchars += write_info.bw_len;
4486 	    }
4487 	}
4488 	write_info.bw_start_lnum = start;
4489 
4490 #ifdef FEAT_PERSISTENT_UNDO
4491 	write_undo_file = (buf->b_p_udf
4492 			    && overwriting
4493 			    && !append
4494 			    && !filtering
4495 			    && reset_changed
4496 			    && !checking_conversion);
4497 	if (write_undo_file)
4498 	    /* Prepare for computing the hash value of the text. */
4499 	    sha256_start(&sha_ctx);
4500 #endif
4501 
4502 	write_info.bw_len = bufsize;
4503 #ifdef HAS_BW_FLAGS
4504 	write_info.bw_flags = wb_flags;
4505 #endif
4506 	fileformat = get_fileformat_force(buf, eap);
4507 	s = buffer;
4508 	len = 0;
4509 	for (lnum = start; lnum <= end; ++lnum)
4510 	{
4511 	    /*
4512 	     * The next while loop is done once for each character written.
4513 	     * Keep it fast!
4514 	     */
4515 	    ptr = ml_get_buf(buf, lnum, FALSE) - 1;
4516 #ifdef FEAT_PERSISTENT_UNDO
4517 	    if (write_undo_file)
4518 		sha256_update(&sha_ctx, ptr + 1,
4519 					      (UINT32_T)(STRLEN(ptr + 1) + 1));
4520 #endif
4521 	    while ((c = *++ptr) != NUL)
4522 	    {
4523 		if (c == NL)
4524 		    *s = NUL;		/* replace newlines with NULs */
4525 		else if (c == CAR && fileformat == EOL_MAC)
4526 		    *s = NL;		/* Mac: replace CRs with NLs */
4527 		else
4528 		    *s = c;
4529 		++s;
4530 		if (++len != bufsize)
4531 		    continue;
4532 		if (buf_write_bytes(&write_info) == FAIL)
4533 		{
4534 		    end = 0;		/* write error: break loop */
4535 		    break;
4536 		}
4537 		nchars += bufsize;
4538 		s = buffer;
4539 		len = 0;
4540 		write_info.bw_start_lnum = lnum;
4541 	    }
4542 	    /* write failed or last line has no EOL: stop here */
4543 	    if (end == 0
4544 		    || (lnum == end
4545 			&& (write_bin || !buf->b_p_fixeol)
4546 			&& (lnum == buf->b_no_eol_lnum
4547 			    || (lnum == buf->b_ml.ml_line_count
4548 							   && !buf->b_p_eol))))
4549 	    {
4550 		++lnum;			/* written the line, count it */
4551 		no_eol = TRUE;
4552 		break;
4553 	    }
4554 	    if (fileformat == EOL_UNIX)
4555 		*s++ = NL;
4556 	    else
4557 	    {
4558 		*s++ = CAR;		    /* EOL_MAC or EOL_DOS: write CR */
4559 		if (fileformat == EOL_DOS)  /* write CR-NL */
4560 		{
4561 		    if (++len == bufsize)
4562 		    {
4563 			if (buf_write_bytes(&write_info) == FAIL)
4564 			{
4565 			    end = 0;	/* write error: break loop */
4566 			    break;
4567 			}
4568 			nchars += bufsize;
4569 			s = buffer;
4570 			len = 0;
4571 		    }
4572 		    *s++ = NL;
4573 		}
4574 	    }
4575 	    if (++len == bufsize && end)
4576 	    {
4577 		if (buf_write_bytes(&write_info) == FAIL)
4578 		{
4579 		    end = 0;		/* write error: break loop */
4580 		    break;
4581 		}
4582 		nchars += bufsize;
4583 		s = buffer;
4584 		len = 0;
4585 
4586 		ui_breakcheck();
4587 		if (got_int)
4588 		{
4589 		    end = 0;		/* Interrupted, break loop */
4590 		    break;
4591 		}
4592 	    }
4593 #ifdef VMS
4594 	    /*
4595 	     * On VMS there is a problem: newlines get added when writing
4596 	     * blocks at a time. Fix it by writing a line at a time.
4597 	     * This is much slower!
4598 	     * Explanation: VAX/DECC RTL insists that records in some RMS
4599 	     * structures end with a newline (carriage return) character, and
4600 	     * if they don't it adds one.
4601 	     * With other RMS structures it works perfect without this fix.
4602 	     */
4603 	    if (buf->b_fab_rfm == FAB$C_VFC
4604 		    || ((buf->b_fab_rat & (FAB$M_FTN | FAB$M_CR)) != 0))
4605 	    {
4606 		int b2write;
4607 
4608 		buf->b_fab_mrs = (buf->b_fab_mrs == 0
4609 			? MIN(4096, bufsize)
4610 			: MIN(buf->b_fab_mrs, bufsize));
4611 
4612 		b2write = len;
4613 		while (b2write > 0)
4614 		{
4615 		    write_info.bw_len = MIN(b2write, buf->b_fab_mrs);
4616 		    if (buf_write_bytes(&write_info) == FAIL)
4617 		    {
4618 			end = 0;
4619 			break;
4620 		    }
4621 		    b2write -= MIN(b2write, buf->b_fab_mrs);
4622 		}
4623 		write_info.bw_len = bufsize;
4624 		nchars += len;
4625 		s = buffer;
4626 		len = 0;
4627 	    }
4628 #endif
4629 	}
4630 	if (len > 0 && end > 0)
4631 	{
4632 	    write_info.bw_len = len;
4633 	    if (buf_write_bytes(&write_info) == FAIL)
4634 		end = 0;		    /* write error */
4635 	    nchars += len;
4636 	}
4637 
4638 	/* Stop when writing done or an error was encountered. */
4639 	if (!checking_conversion || end == 0)
4640 	    break;
4641 
4642 	/* If no error happened until now, writing should be ok, so loop to
4643 	 * really write the buffer. */
4644     }
4645 
4646     /* If we started writing, finish writing. Also when an error was
4647      * encountered. */
4648     if (!checking_conversion)
4649     {
4650 #if defined(UNIX) && defined(HAVE_FSYNC)
4651 	/*
4652 	 * On many journalling file systems there is a bug that causes both the
4653 	 * original and the backup file to be lost when halting the system
4654 	 * right after writing the file.  That's because only the meta-data is
4655 	 * journalled.  Syncing the file slows down the system, but assures it
4656 	 * has been written to disk and we don't lose it.
4657 	 * For a device do try the fsync() but don't complain if it does not
4658 	 * work (could be a pipe).
4659 	 * If the 'fsync' option is FALSE, don't fsync().  Useful for laptops.
4660 	 */
4661 	if (p_fs && vim_fsync(fd) != 0 && !device)
4662 	{
4663 	    errmsg = (char_u *)_(e_fsync);
4664 	    end = 0;
4665 	}
4666 #endif
4667 
4668 #if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
4669 	/* Probably need to set the security context. */
4670 	if (!backup_copy)
4671 	    mch_copy_sec(backup, wfname);
4672 #endif
4673 
4674 #ifdef UNIX
4675 	/* When creating a new file, set its owner/group to that of the
4676 	 * original file.  Get the new device and inode number. */
4677 	if (backup != NULL && !backup_copy)
4678 	{
4679 # ifdef HAVE_FCHOWN
4680 	    stat_T	st;
4681 
4682 	    /* Don't change the owner when it's already OK, some systems remove
4683 	     * permission or ACL stuff. */
4684 	    if (mch_stat((char *)wfname, &st) < 0
4685 		    || st.st_uid != st_old.st_uid
4686 		    || st.st_gid != st_old.st_gid)
4687 	    {
4688 		/* changing owner might not be possible */
4689 		vim_ignored = fchown(fd, st_old.st_uid, -1);
4690 		/* if changing group fails clear the group permissions */
4691 		if (fchown(fd, -1, st_old.st_gid) == -1 && perm > 0)
4692 		    perm &= ~070;
4693 	    }
4694 # endif
4695 	    buf_setino(buf);
4696 	}
4697 	else if (!buf->b_dev_valid)
4698 	    /* Set the inode when creating a new file. */
4699 	    buf_setino(buf);
4700 #endif
4701 
4702 #ifdef UNIX
4703 	if (made_writable)
4704 	    perm &= ~0200;	/* reset 'w' bit for security reasons */
4705 #endif
4706 #ifdef HAVE_FCHMOD
4707 	/* set permission of new file same as old file */
4708 	if (perm >= 0)
4709 	    (void)mch_fsetperm(fd, perm);
4710 #endif
4711 	if (close(fd) != 0)
4712 	{
4713 	    errmsg = (char_u *)_("E512: Close failed");
4714 	    end = 0;
4715 	}
4716 
4717 #ifndef HAVE_FCHMOD
4718 	/* set permission of new file same as old file */
4719 	if (perm >= 0)
4720 	    (void)mch_setperm(wfname, perm);
4721 #endif
4722 #ifdef HAVE_ACL
4723 	/*
4724 	 * Probably need to set the ACL before changing the user (can't set the
4725 	 * ACL on a file the user doesn't own).
4726 	 * On Solaris, with ZFS and the aclmode property set to "discard" (the
4727 	 * default), chmod() discards all part of a file's ACL that don't
4728 	 * represent the mode of the file.  It's non-trivial for us to discover
4729 	 * whether we're in that situation, so we simply always re-set the ACL.
4730 	 */
4731 # ifndef HAVE_SOLARIS_ZFS_ACL
4732 	if (!backup_copy)
4733 # endif
4734 	    mch_set_acl(wfname, acl);
4735 #endif
4736 #ifdef FEAT_CRYPT
4737 	if (buf->b_cryptstate != NULL)
4738 	{
4739 	    crypt_free_state(buf->b_cryptstate);
4740 	    buf->b_cryptstate = NULL;
4741 	}
4742 #endif
4743 
4744 #if defined(FEAT_EVAL)
4745 	if (wfname != fname)
4746 	{
4747 	    /*
4748 	     * The file was written to a temp file, now it needs to be
4749 	     * converted with 'charconvert' to (overwrite) the output file.
4750 	     */
4751 	    if (end != 0)
4752 	    {
4753 		if (eval_charconvert(enc_utf8 ? (char_u *)"utf-8" : p_enc,
4754 						  fenc, wfname, fname) == FAIL)
4755 		{
4756 		    write_info.bw_conv_error = TRUE;
4757 		    end = 0;
4758 		}
4759 	    }
4760 	    mch_remove(wfname);
4761 	    vim_free(wfname);
4762 	}
4763 #endif
4764     }
4765 
4766     if (end == 0)
4767     {
4768 	/*
4769 	 * Error encountered.
4770 	 */
4771 	if (errmsg == NULL)
4772 	{
4773 	    if (write_info.bw_conv_error)
4774 	    {
4775 		if (write_info.bw_conv_error_lnum == 0)
4776 		    errmsg = (char_u *)_("E513: write error, conversion failed (make 'fenc' empty to override)");
4777 		else
4778 		{
4779 		    errmsg_allocated = TRUE;
4780 		    errmsg = alloc(300);
4781 		    vim_snprintf((char *)errmsg, 300, _("E513: write error, conversion failed in line %ld (make 'fenc' empty to override)"),
4782 					 (long)write_info.bw_conv_error_lnum);
4783 		}
4784 	    }
4785 	    else if (got_int)
4786 		errmsg = (char_u *)_(e_interr);
4787 	    else
4788 		errmsg = (char_u *)_("E514: write error (file system full?)");
4789 	}
4790 
4791 	/*
4792 	 * If we have a backup file, try to put it in place of the new file,
4793 	 * because the new file is probably corrupt.  This avoids losing the
4794 	 * original file when trying to make a backup when writing the file a
4795 	 * second time.
4796 	 * When "backup_copy" is set we need to copy the backup over the new
4797 	 * file.  Otherwise rename the backup file.
4798 	 * If this is OK, don't give the extra warning message.
4799 	 */
4800 	if (backup != NULL)
4801 	{
4802 	    if (backup_copy)
4803 	    {
4804 		/* This may take a while, if we were interrupted let the user
4805 		 * know we got the message. */
4806 		if (got_int)
4807 		{
4808 		    msg(_(e_interr));
4809 		    out_flush();
4810 		}
4811 		if ((fd = mch_open((char *)backup, O_RDONLY | O_EXTRA, 0)) >= 0)
4812 		{
4813 		    if ((write_info.bw_fd = mch_open((char *)fname,
4814 				    O_WRONLY | O_CREAT | O_TRUNC | O_EXTRA,
4815 							   perm & 0777)) >= 0)
4816 		    {
4817 			/* copy the file. */
4818 			write_info.bw_buf = smallbuf;
4819 #ifdef HAS_BW_FLAGS
4820 			write_info.bw_flags = FIO_NOCONVERT;
4821 #endif
4822 			while ((write_info.bw_len = read_eintr(fd, smallbuf,
4823 						      SMBUFSIZE)) > 0)
4824 			    if (buf_write_bytes(&write_info) == FAIL)
4825 				break;
4826 
4827 			if (close(write_info.bw_fd) >= 0
4828 						   && write_info.bw_len == 0)
4829 			    end = 1;		/* success */
4830 		    }
4831 		    close(fd);	/* ignore errors for closing read file */
4832 		}
4833 	    }
4834 	    else
4835 	    {
4836 		if (vim_rename(backup, fname) == 0)
4837 		    end = 1;
4838 	    }
4839 	}
4840 	goto fail;
4841     }
4842 
4843     lnum -= start;	    /* compute number of written lines */
4844     --no_wait_return;	    /* may wait for return now */
4845 
4846 #if !(defined(UNIX) || defined(VMS))
4847     fname = sfname;	    /* use shortname now, for the messages */
4848 #endif
4849     if (!filtering)
4850     {
4851 	msg_add_fname(buf, fname);	/* put fname in IObuff with quotes */
4852 	c = FALSE;
4853 	if (write_info.bw_conv_error)
4854 	{
4855 	    STRCAT(IObuff, _(" CONVERSION ERROR"));
4856 	    c = TRUE;
4857 	    if (write_info.bw_conv_error_lnum != 0)
4858 		vim_snprintf_add((char *)IObuff, IOSIZE, _(" in line %ld;"),
4859 			(long)write_info.bw_conv_error_lnum);
4860 	}
4861 	else if (notconverted)
4862 	{
4863 	    STRCAT(IObuff, _("[NOT converted]"));
4864 	    c = TRUE;
4865 	}
4866 	else if (converted)
4867 	{
4868 	    STRCAT(IObuff, _("[converted]"));
4869 	    c = TRUE;
4870 	}
4871 	if (device)
4872 	{
4873 	    STRCAT(IObuff, _("[Device]"));
4874 	    c = TRUE;
4875 	}
4876 	else if (newfile)
4877 	{
4878 	    STRCAT(IObuff, shortmess(SHM_NEW) ? _("[New]") : _("[New File]"));
4879 	    c = TRUE;
4880 	}
4881 	if (no_eol)
4882 	{
4883 	    msg_add_eol();
4884 	    c = TRUE;
4885 	}
4886 	/* may add [unix/dos/mac] */
4887 	if (msg_add_fileformat(fileformat))
4888 	    c = TRUE;
4889 #ifdef FEAT_CRYPT
4890 	if (wb_flags & FIO_ENCRYPTED)
4891 	{
4892 	    crypt_append_msg(buf);
4893 	    c = TRUE;
4894 	}
4895 #endif
4896 	msg_add_lines(c, (long)lnum, nchars);	/* add line/char count */
4897 	if (!shortmess(SHM_WRITE))
4898 	{
4899 	    if (append)
4900 		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [a]") : _(" appended"));
4901 	    else
4902 		STRCAT(IObuff, shortmess(SHM_WRI) ? _(" [w]") : _(" written"));
4903 	}
4904 
4905 	set_keep_msg((char_u *)msg_trunc_attr((char *)IObuff, FALSE, 0), 0);
4906     }
4907 
4908     /* When written everything correctly: reset 'modified'.  Unless not
4909      * writing to the original file and '+' is not in 'cpoptions'. */
4910     if (reset_changed && whole && !append
4911 	    && !write_info.bw_conv_error
4912 	    && (overwriting || vim_strchr(p_cpo, CPO_PLUS) != NULL))
4913     {
4914 	unchanged(buf, TRUE);
4915 	/* b:changedtick is always incremented in unchanged() but that
4916 	 * should not trigger a TextChanged event. */
4917 	if (buf->b_last_changedtick + 1 == CHANGEDTICK(buf))
4918 	    buf->b_last_changedtick = CHANGEDTICK(buf);
4919 	u_unchanged(buf);
4920 	u_update_save_nr(buf);
4921     }
4922 
4923     /*
4924      * If written to the current file, update the timestamp of the swap file
4925      * and reset the BF_WRITE_MASK flags. Also sets buf->b_mtime.
4926      */
4927     if (overwriting)
4928     {
4929 	ml_timestamp(buf);
4930 	if (append)
4931 	    buf->b_flags &= ~BF_NEW;
4932 	else
4933 	    buf->b_flags &= ~BF_WRITE_MASK;
4934     }
4935 
4936     /*
4937      * If we kept a backup until now, and we are in patch mode, then we make
4938      * the backup file our 'original' file.
4939      */
4940     if (*p_pm && dobackup)
4941     {
4942 	char *org = (char *)buf_modname((buf->b_p_sn || buf->b_shortname),
4943 							  fname, p_pm, FALSE);
4944 
4945 	if (backup != NULL)
4946 	{
4947 	    stat_T	st;
4948 
4949 	    /*
4950 	     * If the original file does not exist yet
4951 	     * the current backup file becomes the original file
4952 	     */
4953 	    if (org == NULL)
4954 		emsg(_("E205: Patchmode: can't save original file"));
4955 	    else if (mch_stat(org, &st) < 0)
4956 	    {
4957 		vim_rename(backup, (char_u *)org);
4958 		VIM_CLEAR(backup);	    /* don't delete the file */
4959 #ifdef UNIX
4960 		set_file_time((char_u *)org, st_old.st_atime, st_old.st_mtime);
4961 #endif
4962 	    }
4963 	}
4964 	/*
4965 	 * If there is no backup file, remember that a (new) file was
4966 	 * created.
4967 	 */
4968 	else
4969 	{
4970 	    int empty_fd;
4971 
4972 	    if (org == NULL
4973 		    || (empty_fd = mch_open(org,
4974 				      O_CREAT | O_EXTRA | O_EXCL | O_NOFOLLOW,
4975 					perm < 0 ? 0666 : (perm & 0777))) < 0)
4976 	      emsg(_("E206: patchmode: can't touch empty original file"));
4977 	    else
4978 	      close(empty_fd);
4979 	}
4980 	if (org != NULL)
4981 	{
4982 	    mch_setperm((char_u *)org, mch_getperm(fname) & 0777);
4983 	    vim_free(org);
4984 	}
4985     }
4986 
4987     /*
4988      * Remove the backup unless 'backup' option is set
4989      */
4990     if (!p_bk && backup != NULL && mch_remove(backup) != 0)
4991 	emsg(_("E207: Can't delete backup file"));
4992 
4993     goto nofail;
4994 
4995     /*
4996      * Finish up.  We get here either after failure or success.
4997      */
4998 fail:
4999     --no_wait_return;		/* may wait for return now */
5000 nofail:
5001 
5002     /* Done saving, we accept changed buffer warnings again */
5003     buf->b_saving = FALSE;
5004 
5005     vim_free(backup);
5006     if (buffer != smallbuf)
5007 	vim_free(buffer);
5008     vim_free(fenc_tofree);
5009     vim_free(write_info.bw_conv_buf);
5010 #ifdef USE_ICONV
5011     if (write_info.bw_iconv_fd != (iconv_t)-1)
5012     {
5013 	iconv_close(write_info.bw_iconv_fd);
5014 	write_info.bw_iconv_fd = (iconv_t)-1;
5015     }
5016 #endif
5017 #ifdef HAVE_ACL
5018     mch_free_acl(acl);
5019 #endif
5020 
5021     if (errmsg != NULL)
5022     {
5023 	int numlen = errnum != NULL ? (int)STRLEN(errnum) : 0;
5024 
5025 	attr = HL_ATTR(HLF_E);	/* set highlight for error messages */
5026 	msg_add_fname(buf,
5027 #ifndef UNIX
5028 		sfname
5029 #else
5030 		fname
5031 #endif
5032 		     );		/* put file name in IObuff with quotes */
5033 	if (STRLEN(IObuff) + STRLEN(errmsg) + numlen >= IOSIZE)
5034 	    IObuff[IOSIZE - STRLEN(errmsg) - numlen - 1] = NUL;
5035 	/* If the error message has the form "is ...", put the error number in
5036 	 * front of the file name. */
5037 	if (errnum != NULL)
5038 	{
5039 	    STRMOVE(IObuff + numlen, IObuff);
5040 	    mch_memmove(IObuff, errnum, (size_t)numlen);
5041 	}
5042 	STRCAT(IObuff, errmsg);
5043 	emsg((char *)IObuff);
5044 	if (errmsg_allocated)
5045 	    vim_free(errmsg);
5046 
5047 	retval = FAIL;
5048 	if (end == 0)
5049 	{
5050 	    msg_puts_attr(_("\nWARNING: Original file may be lost or damaged\n"),
5051 		    attr | MSG_HIST);
5052 	    msg_puts_attr(_("don't quit the editor until the file is successfully written!"),
5053 		    attr | MSG_HIST);
5054 
5055 	    /* Update the timestamp to avoid an "overwrite changed file"
5056 	     * prompt when writing again. */
5057 	    if (mch_stat((char *)fname, &st_old) >= 0)
5058 	    {
5059 		buf_store_time(buf, &st_old, fname);
5060 		buf->b_mtime_read = buf->b_mtime;
5061 	    }
5062 	}
5063     }
5064     msg_scroll = msg_save;
5065 
5066 #ifdef FEAT_PERSISTENT_UNDO
5067     /*
5068      * When writing the whole file and 'undofile' is set, also write the undo
5069      * file.
5070      */
5071     if (retval == OK && write_undo_file)
5072     {
5073 	char_u	    hash[UNDO_HASH_SIZE];
5074 
5075 	sha256_finish(&sha_ctx, hash);
5076 	u_write_undo(NULL, FALSE, buf, hash);
5077     }
5078 #endif
5079 
5080 #ifdef FEAT_EVAL
5081     if (!should_abort(retval))
5082 #else
5083     if (!got_int)
5084 #endif
5085     {
5086 	aco_save_T	aco;
5087 
5088 	curbuf->b_no_eol_lnum = 0;  /* in case it was set by the previous read */
5089 
5090 	/*
5091 	 * Apply POST autocommands.
5092 	 * Careful: The autocommands may call buf_write() recursively!
5093 	 */
5094 	aucmd_prepbuf(&aco, buf);
5095 
5096 	if (append)
5097 	    apply_autocmds_exarg(EVENT_FILEAPPENDPOST, fname, fname,
5098 							  FALSE, curbuf, eap);
5099 	else if (filtering)
5100 	    apply_autocmds_exarg(EVENT_FILTERWRITEPOST, NULL, fname,
5101 							  FALSE, curbuf, eap);
5102 	else if (reset_changed && whole)
5103 	    apply_autocmds_exarg(EVENT_BUFWRITEPOST, fname, fname,
5104 							  FALSE, curbuf, eap);
5105 	else
5106 	    apply_autocmds_exarg(EVENT_FILEWRITEPOST, fname, fname,
5107 							  FALSE, curbuf, eap);
5108 
5109 	/* restore curwin/curbuf and a few other things */
5110 	aucmd_restbuf(&aco);
5111 
5112 #ifdef FEAT_EVAL
5113 	if (aborting())	    /* autocmds may abort script processing */
5114 	    retval = FALSE;
5115 #endif
5116     }
5117 
5118     got_int |= prev_got_int;
5119 
5120     return retval;
5121 }
5122 
5123 #if defined(HAVE_FSYNC) || defined(PROTO)
5124 /*
5125  * Call fsync() with Mac-specific exception.
5126  * Return fsync() result: zero for success.
5127  */
5128     int
5129 vim_fsync(int fd)
5130 {
5131     int r;
5132 
5133 # ifdef MACOS_X
5134     r = fcntl(fd, F_FULLFSYNC);
5135     if (r != 0)  // F_FULLFSYNC not working or not supported
5136 # endif
5137 	r = fsync(fd);
5138     return r;
5139 }
5140 #endif
5141 
5142 /*
5143  * Set the name of the current buffer.  Use when the buffer doesn't have a
5144  * name and a ":r" or ":w" command with a file name is used.
5145  */
5146     static int
5147 set_rw_fname(char_u *fname, char_u *sfname)
5148 {
5149     buf_T	*buf = curbuf;
5150 
5151     /* It's like the unnamed buffer is deleted.... */
5152     if (curbuf->b_p_bl)
5153 	apply_autocmds(EVENT_BUFDELETE, NULL, NULL, FALSE, curbuf);
5154     apply_autocmds(EVENT_BUFWIPEOUT, NULL, NULL, FALSE, curbuf);
5155 #ifdef FEAT_EVAL
5156     if (aborting())	    /* autocmds may abort script processing */
5157 	return FAIL;
5158 #endif
5159     if (curbuf != buf)
5160     {
5161 	/* We are in another buffer now, don't do the renaming. */
5162 	emsg(_(e_auchangedbuf));
5163 	return FAIL;
5164     }
5165 
5166     if (setfname(curbuf, fname, sfname, FALSE) == OK)
5167 	curbuf->b_flags |= BF_NOTEDITED;
5168 
5169     /* ....and a new named one is created */
5170     apply_autocmds(EVENT_BUFNEW, NULL, NULL, FALSE, curbuf);
5171     if (curbuf->b_p_bl)
5172 	apply_autocmds(EVENT_BUFADD, NULL, NULL, FALSE, curbuf);
5173 #ifdef FEAT_EVAL
5174     if (aborting())	    /* autocmds may abort script processing */
5175 	return FAIL;
5176 #endif
5177 
5178     /* Do filetype detection now if 'filetype' is empty. */
5179     if (*curbuf->b_p_ft == NUL)
5180     {
5181 	if (au_has_group((char_u *)"filetypedetect"))
5182 	    (void)do_doautocmd((char_u *)"filetypedetect BufRead", FALSE, NULL);
5183 	do_modelines(0);
5184     }
5185 
5186     return OK;
5187 }
5188 
5189 /*
5190  * Put file name into IObuff with quotes.
5191  */
5192     void
5193 msg_add_fname(buf_T *buf, char_u *fname)
5194 {
5195     if (fname == NULL)
5196 	fname = (char_u *)"-stdin-";
5197     home_replace(buf, fname, IObuff + 1, IOSIZE - 4, TRUE);
5198     IObuff[0] = '"';
5199     STRCAT(IObuff, "\" ");
5200 }
5201 
5202 /*
5203  * Append message for text mode to IObuff.
5204  * Return TRUE if something appended.
5205  */
5206     static int
5207 msg_add_fileformat(int eol_type)
5208 {
5209 #ifndef USE_CRNL
5210     if (eol_type == EOL_DOS)
5211     {
5212 	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[dos]") : _("[dos format]"));
5213 	return TRUE;
5214     }
5215 #endif
5216     if (eol_type == EOL_MAC)
5217     {
5218 	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[mac]") : _("[mac format]"));
5219 	return TRUE;
5220     }
5221 #ifdef USE_CRNL
5222     if (eol_type == EOL_UNIX)
5223     {
5224 	STRCAT(IObuff, shortmess(SHM_TEXT) ? _("[unix]") : _("[unix format]"));
5225 	return TRUE;
5226     }
5227 #endif
5228     return FALSE;
5229 }
5230 
5231 /*
5232  * Append line and character count to IObuff.
5233  */
5234     void
5235 msg_add_lines(
5236     int	    insert_space,
5237     long    lnum,
5238     off_T   nchars)
5239 {
5240     char_u  *p;
5241 
5242     p = IObuff + STRLEN(IObuff);
5243 
5244     if (insert_space)
5245 	*p++ = ' ';
5246     if (shortmess(SHM_LINES))
5247 	vim_snprintf((char *)p, IOSIZE - (p - IObuff),
5248 		"%ldL, %lldC", lnum, (long_long_T)nchars);
5249     else
5250     {
5251 	sprintf((char *)p, NGETTEXT("%ld line, ", "%ld lines, ", lnum), lnum);
5252 	p += STRLEN(p);
5253 	vim_snprintf((char *)p, IOSIZE - (p - IObuff),
5254 		NGETTEXT("%lld character", "%lld characters", nchars),
5255 		(long_long_T)nchars);
5256     }
5257 }
5258 
5259 /*
5260  * Append message for missing line separator to IObuff.
5261  */
5262     static void
5263 msg_add_eol(void)
5264 {
5265     STRCAT(IObuff, shortmess(SHM_LAST) ? _("[noeol]") : _("[Incomplete last line]"));
5266 }
5267 
5268 /*
5269  * Check modification time of file, before writing to it.
5270  * The size isn't checked, because using a tool like "gzip" takes care of
5271  * using the same timestamp but can't set the size.
5272  */
5273     static int
5274 check_mtime(buf_T *buf, stat_T *st)
5275 {
5276     if (buf->b_mtime_read != 0
5277 	    && time_differs((long)st->st_mtime, buf->b_mtime_read))
5278     {
5279 	msg_scroll = TRUE;	    /* don't overwrite messages here */
5280 	msg_silent = 0;		    /* must give this prompt */
5281 	/* don't use emsg() here, don't want to flush the buffers */
5282 	msg_attr(_("WARNING: The file has been changed since reading it!!!"),
5283 						       HL_ATTR(HLF_E));
5284 	if (ask_yesno((char_u *)_("Do you really want to write to it"),
5285 								 TRUE) == 'n')
5286 	    return FAIL;
5287 	msg_scroll = FALSE;	    /* always overwrite the file message now */
5288     }
5289     return OK;
5290 }
5291 
5292     static int
5293 time_differs(long t1, long t2)
5294 {
5295 #if defined(__linux__) || defined(MSWIN)
5296     /* On a FAT filesystem, esp. under Linux, there are only 5 bits to store
5297      * the seconds.  Since the roundoff is done when flushing the inode, the
5298      * time may change unexpectedly by one second!!! */
5299     return (t1 - t2 > 1 || t2 - t1 > 1);
5300 #else
5301     return (t1 != t2);
5302 #endif
5303 }
5304 
5305 /*
5306  * Call write() to write a number of bytes to the file.
5307  * Handles encryption and 'encoding' conversion.
5308  *
5309  * Return FAIL for failure, OK otherwise.
5310  */
5311     static int
5312 buf_write_bytes(struct bw_info *ip)
5313 {
5314     int		wlen;
5315     char_u	*buf = ip->bw_buf;	/* data to write */
5316     int		len = ip->bw_len;	/* length of data */
5317 #ifdef HAS_BW_FLAGS
5318     int		flags = ip->bw_flags;	/* extra flags */
5319 #endif
5320 
5321     /*
5322      * Skip conversion when writing the crypt magic number or the BOM.
5323      */
5324     if (!(flags & FIO_NOCONVERT))
5325     {
5326 	char_u		*p;
5327 	unsigned	c;
5328 	int		n;
5329 
5330 	if (flags & FIO_UTF8)
5331 	{
5332 	    /*
5333 	     * Convert latin1 in the buffer to UTF-8 in the file.
5334 	     */
5335 	    p = ip->bw_conv_buf;	/* translate to buffer */
5336 	    for (wlen = 0; wlen < len; ++wlen)
5337 		p += utf_char2bytes(buf[wlen], p);
5338 	    buf = ip->bw_conv_buf;
5339 	    len = (int)(p - ip->bw_conv_buf);
5340 	}
5341 	else if (flags & (FIO_UCS4 | FIO_UTF16 | FIO_UCS2 | FIO_LATIN1))
5342 	{
5343 	    /*
5344 	     * Convert UTF-8 bytes in the buffer to UCS-2, UCS-4, UTF-16 or
5345 	     * Latin1 chars in the file.
5346 	     */
5347 	    if (flags & FIO_LATIN1)
5348 		p = buf;	/* translate in-place (can only get shorter) */
5349 	    else
5350 		p = ip->bw_conv_buf;	/* translate to buffer */
5351 	    for (wlen = 0; wlen < len; wlen += n)
5352 	    {
5353 		if (wlen == 0 && ip->bw_restlen != 0)
5354 		{
5355 		    int		l;
5356 
5357 		    /* Use remainder of previous call.  Append the start of
5358 		     * buf[] to get a full sequence.  Might still be too
5359 		     * short! */
5360 		    l = CONV_RESTLEN - ip->bw_restlen;
5361 		    if (l > len)
5362 			l = len;
5363 		    mch_memmove(ip->bw_rest + ip->bw_restlen, buf, (size_t)l);
5364 		    n = utf_ptr2len_len(ip->bw_rest, ip->bw_restlen + l);
5365 		    if (n > ip->bw_restlen + len)
5366 		    {
5367 			/* We have an incomplete byte sequence at the end to
5368 			 * be written.  We can't convert it without the
5369 			 * remaining bytes.  Keep them for the next call. */
5370 			if (ip->bw_restlen + len > CONV_RESTLEN)
5371 			    return FAIL;
5372 			ip->bw_restlen += len;
5373 			break;
5374 		    }
5375 		    if (n > 1)
5376 			c = utf_ptr2char(ip->bw_rest);
5377 		    else
5378 			c = ip->bw_rest[0];
5379 		    if (n >= ip->bw_restlen)
5380 		    {
5381 			n -= ip->bw_restlen;
5382 			ip->bw_restlen = 0;
5383 		    }
5384 		    else
5385 		    {
5386 			ip->bw_restlen -= n;
5387 			mch_memmove(ip->bw_rest, ip->bw_rest + n,
5388 						      (size_t)ip->bw_restlen);
5389 			n = 0;
5390 		    }
5391 		}
5392 		else
5393 		{
5394 		    n = utf_ptr2len_len(buf + wlen, len - wlen);
5395 		    if (n > len - wlen)
5396 		    {
5397 			/* We have an incomplete byte sequence at the end to
5398 			 * be written.  We can't convert it without the
5399 			 * remaining bytes.  Keep them for the next call. */
5400 			if (len - wlen > CONV_RESTLEN)
5401 			    return FAIL;
5402 			ip->bw_restlen = len - wlen;
5403 			mch_memmove(ip->bw_rest, buf + wlen,
5404 						      (size_t)ip->bw_restlen);
5405 			break;
5406 		    }
5407 		    if (n > 1)
5408 			c = utf_ptr2char(buf + wlen);
5409 		    else
5410 			c = buf[wlen];
5411 		}
5412 
5413 		if (ucs2bytes(c, &p, flags) && !ip->bw_conv_error)
5414 		{
5415 		    ip->bw_conv_error = TRUE;
5416 		    ip->bw_conv_error_lnum = ip->bw_start_lnum;
5417 		}
5418 		if (c == NL)
5419 		    ++ip->bw_start_lnum;
5420 	    }
5421 	    if (flags & FIO_LATIN1)
5422 		len = (int)(p - buf);
5423 	    else
5424 	    {
5425 		buf = ip->bw_conv_buf;
5426 		len = (int)(p - ip->bw_conv_buf);
5427 	    }
5428 	}
5429 
5430 #ifdef MSWIN
5431 	else if (flags & FIO_CODEPAGE)
5432 	{
5433 	    /*
5434 	     * Convert UTF-8 or codepage to UCS-2 and then to MS-Windows
5435 	     * codepage.
5436 	     */
5437 	    char_u	*from;
5438 	    size_t	fromlen;
5439 	    char_u	*to;
5440 	    int		u8c;
5441 	    BOOL	bad = FALSE;
5442 	    int		needed;
5443 
5444 	    if (ip->bw_restlen > 0)
5445 	    {
5446 		/* Need to concatenate the remainder of the previous call and
5447 		 * the bytes of the current call.  Use the end of the
5448 		 * conversion buffer for this. */
5449 		fromlen = len + ip->bw_restlen;
5450 		from = ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
5451 		mch_memmove(from, ip->bw_rest, (size_t)ip->bw_restlen);
5452 		mch_memmove(from + ip->bw_restlen, buf, (size_t)len);
5453 	    }
5454 	    else
5455 	    {
5456 		from = buf;
5457 		fromlen = len;
5458 	    }
5459 
5460 	    to = ip->bw_conv_buf;
5461 	    if (enc_utf8)
5462 	    {
5463 		/* Convert from UTF-8 to UCS-2, to the start of the buffer.
5464 		 * The buffer has been allocated to be big enough. */
5465 		while (fromlen > 0)
5466 		{
5467 		    n = (int)utf_ptr2len_len(from, (int)fromlen);
5468 		    if (n > (int)fromlen)	/* incomplete byte sequence */
5469 			break;
5470 		    u8c = utf_ptr2char(from);
5471 		    *to++ = (u8c & 0xff);
5472 		    *to++ = (u8c >> 8);
5473 		    fromlen -= n;
5474 		    from += n;
5475 		}
5476 
5477 		/* Copy remainder to ip->bw_rest[] to be used for the next
5478 		 * call. */
5479 		if (fromlen > CONV_RESTLEN)
5480 		{
5481 		    /* weird overlong sequence */
5482 		    ip->bw_conv_error = TRUE;
5483 		    return FAIL;
5484 		}
5485 		mch_memmove(ip->bw_rest, from, fromlen);
5486 		ip->bw_restlen = (int)fromlen;
5487 	    }
5488 	    else
5489 	    {
5490 		/* Convert from enc_codepage to UCS-2, to the start of the
5491 		 * buffer.  The buffer has been allocated to be big enough. */
5492 		ip->bw_restlen = 0;
5493 		needed = MultiByteToWideChar(enc_codepage,
5494 			     MB_ERR_INVALID_CHARS, (LPCSTR)from, (int)fromlen,
5495 								     NULL, 0);
5496 		if (needed == 0)
5497 		{
5498 		    /* When conversion fails there may be a trailing byte. */
5499 		    needed = MultiByteToWideChar(enc_codepage,
5500 			 MB_ERR_INVALID_CHARS, (LPCSTR)from, (int)fromlen - 1,
5501 								     NULL, 0);
5502 		    if (needed == 0)
5503 		    {
5504 			/* Conversion doesn't work. */
5505 			ip->bw_conv_error = TRUE;
5506 			return FAIL;
5507 		    }
5508 		    /* Save the trailing byte for the next call. */
5509 		    ip->bw_rest[0] = from[fromlen - 1];
5510 		    ip->bw_restlen = 1;
5511 		}
5512 		needed = MultiByteToWideChar(enc_codepage, MB_ERR_INVALID_CHARS,
5513 				(LPCSTR)from, (int)(fromlen - ip->bw_restlen),
5514 							  (LPWSTR)to, needed);
5515 		if (needed == 0)
5516 		{
5517 		    /* Safety check: Conversion doesn't work. */
5518 		    ip->bw_conv_error = TRUE;
5519 		    return FAIL;
5520 		}
5521 		to += needed * 2;
5522 	    }
5523 
5524 	    fromlen = to - ip->bw_conv_buf;
5525 	    buf = to;
5526 # ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
5527 	    if (FIO_GET_CP(flags) == CP_UTF8)
5528 	    {
5529 		/* Convert from UCS-2 to UTF-8, using the remainder of the
5530 		 * conversion buffer.  Fails when out of space. */
5531 		for (from = ip->bw_conv_buf; fromlen > 1; fromlen -= 2)
5532 		{
5533 		    u8c = *from++;
5534 		    u8c += (*from++ << 8);
5535 		    to += utf_char2bytes(u8c, to);
5536 		    if (to + 6 >= ip->bw_conv_buf + ip->bw_conv_buflen)
5537 		    {
5538 			ip->bw_conv_error = TRUE;
5539 			return FAIL;
5540 		    }
5541 		}
5542 		len = (int)(to - buf);
5543 	    }
5544 	    else
5545 # endif
5546 	    {
5547 		/* Convert from UCS-2 to the codepage, using the remainder of
5548 		 * the conversion buffer.  If the conversion uses the default
5549 		 * character "0", the data doesn't fit in this encoding, so
5550 		 * fail. */
5551 		len = WideCharToMultiByte(FIO_GET_CP(flags), 0,
5552 			(LPCWSTR)ip->bw_conv_buf, (int)fromlen / sizeof(WCHAR),
5553 			(LPSTR)to, (int)(ip->bw_conv_buflen - fromlen), 0,
5554 									&bad);
5555 		if (bad)
5556 		{
5557 		    ip->bw_conv_error = TRUE;
5558 		    return FAIL;
5559 		}
5560 	    }
5561 	}
5562 #endif
5563 
5564 #ifdef MACOS_CONVERT
5565 	else if (flags & FIO_MACROMAN)
5566 	{
5567 	    /*
5568 	     * Convert UTF-8 or latin1 to Apple MacRoman.
5569 	     */
5570 	    char_u	*from;
5571 	    size_t	fromlen;
5572 
5573 	    if (ip->bw_restlen > 0)
5574 	    {
5575 		/* Need to concatenate the remainder of the previous call and
5576 		 * the bytes of the current call.  Use the end of the
5577 		 * conversion buffer for this. */
5578 		fromlen = len + ip->bw_restlen;
5579 		from = ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
5580 		mch_memmove(from, ip->bw_rest, (size_t)ip->bw_restlen);
5581 		mch_memmove(from + ip->bw_restlen, buf, (size_t)len);
5582 	    }
5583 	    else
5584 	    {
5585 		from = buf;
5586 		fromlen = len;
5587 	    }
5588 
5589 	    if (enc2macroman(from, fromlen,
5590 			ip->bw_conv_buf, &len, ip->bw_conv_buflen,
5591 			ip->bw_rest, &ip->bw_restlen) == FAIL)
5592 	    {
5593 		ip->bw_conv_error = TRUE;
5594 		return FAIL;
5595 	    }
5596 	    buf = ip->bw_conv_buf;
5597 	}
5598 #endif
5599 
5600 #ifdef USE_ICONV
5601 	if (ip->bw_iconv_fd != (iconv_t)-1)
5602 	{
5603 	    const char	*from;
5604 	    size_t	fromlen;
5605 	    char	*to;
5606 	    size_t	tolen;
5607 
5608 	    /* Convert with iconv(). */
5609 	    if (ip->bw_restlen > 0)
5610 	    {
5611 		char *fp;
5612 
5613 		/* Need to concatenate the remainder of the previous call and
5614 		 * the bytes of the current call.  Use the end of the
5615 		 * conversion buffer for this. */
5616 		fromlen = len + ip->bw_restlen;
5617 		fp = (char *)ip->bw_conv_buf + ip->bw_conv_buflen - fromlen;
5618 		mch_memmove(fp, ip->bw_rest, (size_t)ip->bw_restlen);
5619 		mch_memmove(fp + ip->bw_restlen, buf, (size_t)len);
5620 		from = fp;
5621 		tolen = ip->bw_conv_buflen - fromlen;
5622 	    }
5623 	    else
5624 	    {
5625 		from = (const char *)buf;
5626 		fromlen = len;
5627 		tolen = ip->bw_conv_buflen;
5628 	    }
5629 	    to = (char *)ip->bw_conv_buf;
5630 
5631 	    if (ip->bw_first)
5632 	    {
5633 		size_t	save_len = tolen;
5634 
5635 		/* output the initial shift state sequence */
5636 		(void)iconv(ip->bw_iconv_fd, NULL, NULL, &to, &tolen);
5637 
5638 		/* There is a bug in iconv() on Linux (which appears to be
5639 		 * wide-spread) which sets "to" to NULL and messes up "tolen".
5640 		 */
5641 		if (to == NULL)
5642 		{
5643 		    to = (char *)ip->bw_conv_buf;
5644 		    tolen = save_len;
5645 		}
5646 		ip->bw_first = FALSE;
5647 	    }
5648 
5649 	    /*
5650 	     * If iconv() has an error or there is not enough room, fail.
5651 	     */
5652 	    if ((iconv(ip->bw_iconv_fd, (void *)&from, &fromlen, &to, &tolen)
5653 			== (size_t)-1 && ICONV_ERRNO != ICONV_EINVAL)
5654 						    || fromlen > CONV_RESTLEN)
5655 	    {
5656 		ip->bw_conv_error = TRUE;
5657 		return FAIL;
5658 	    }
5659 
5660 	    /* copy remainder to ip->bw_rest[] to be used for the next call. */
5661 	    if (fromlen > 0)
5662 		mch_memmove(ip->bw_rest, (void *)from, fromlen);
5663 	    ip->bw_restlen = (int)fromlen;
5664 
5665 	    buf = ip->bw_conv_buf;
5666 	    len = (int)((char_u *)to - ip->bw_conv_buf);
5667 	}
5668 #endif
5669     }
5670 
5671     if (ip->bw_fd < 0)
5672 	/* Only checking conversion, which is OK if we get here. */
5673 	return OK;
5674 
5675 #ifdef FEAT_CRYPT
5676     if (flags & FIO_ENCRYPTED)
5677     {
5678 	/* Encrypt the data. Do it in-place if possible, otherwise use an
5679 	 * allocated buffer. */
5680 # ifdef CRYPT_NOT_INPLACE
5681 	if (crypt_works_inplace(ip->bw_buffer->b_cryptstate))
5682 	{
5683 # endif
5684 	    crypt_encode_inplace(ip->bw_buffer->b_cryptstate, buf, len);
5685 # ifdef CRYPT_NOT_INPLACE
5686 	}
5687 	else
5688 	{
5689 	    char_u *outbuf;
5690 
5691 	    len = crypt_encode_alloc(curbuf->b_cryptstate, buf, len, &outbuf);
5692 	    if (len == 0)
5693 		return OK;  /* Crypt layer is buffering, will flush later. */
5694 	    wlen = write_eintr(ip->bw_fd, outbuf, len);
5695 	    vim_free(outbuf);
5696 	    return (wlen < len) ? FAIL : OK;
5697 	}
5698 # endif
5699     }
5700 #endif
5701 
5702     wlen = write_eintr(ip->bw_fd, buf, len);
5703     return (wlen < len) ? FAIL : OK;
5704 }
5705 
5706 /*
5707  * Convert a Unicode character to bytes.
5708  * Return TRUE for an error, FALSE when it's OK.
5709  */
5710     static int
5711 ucs2bytes(
5712     unsigned	c,		/* in: character */
5713     char_u	**pp,		/* in/out: pointer to result */
5714     int		flags)		/* FIO_ flags */
5715 {
5716     char_u	*p = *pp;
5717     int		error = FALSE;
5718     int		cc;
5719 
5720 
5721     if (flags & FIO_UCS4)
5722     {
5723 	if (flags & FIO_ENDIAN_L)
5724 	{
5725 	    *p++ = c;
5726 	    *p++ = (c >> 8);
5727 	    *p++ = (c >> 16);
5728 	    *p++ = (c >> 24);
5729 	}
5730 	else
5731 	{
5732 	    *p++ = (c >> 24);
5733 	    *p++ = (c >> 16);
5734 	    *p++ = (c >> 8);
5735 	    *p++ = c;
5736 	}
5737     }
5738     else if (flags & (FIO_UCS2 | FIO_UTF16))
5739     {
5740 	if (c >= 0x10000)
5741 	{
5742 	    if (flags & FIO_UTF16)
5743 	    {
5744 		/* Make two words, ten bits of the character in each.  First
5745 		 * word is 0xd800 - 0xdbff, second one 0xdc00 - 0xdfff */
5746 		c -= 0x10000;
5747 		if (c >= 0x100000)
5748 		    error = TRUE;
5749 		cc = ((c >> 10) & 0x3ff) + 0xd800;
5750 		if (flags & FIO_ENDIAN_L)
5751 		{
5752 		    *p++ = cc;
5753 		    *p++ = ((unsigned)cc >> 8);
5754 		}
5755 		else
5756 		{
5757 		    *p++ = ((unsigned)cc >> 8);
5758 		    *p++ = cc;
5759 		}
5760 		c = (c & 0x3ff) + 0xdc00;
5761 	    }
5762 	    else
5763 		error = TRUE;
5764 	}
5765 	if (flags & FIO_ENDIAN_L)
5766 	{
5767 	    *p++ = c;
5768 	    *p++ = (c >> 8);
5769 	}
5770 	else
5771 	{
5772 	    *p++ = (c >> 8);
5773 	    *p++ = c;
5774 	}
5775     }
5776     else    /* Latin1 */
5777     {
5778 	if (c >= 0x100)
5779 	{
5780 	    error = TRUE;
5781 	    *p++ = 0xBF;
5782 	}
5783 	else
5784 	    *p++ = c;
5785     }
5786 
5787     *pp = p;
5788     return error;
5789 }
5790 
5791 /*
5792  * Return TRUE if file encoding "fenc" requires conversion from or to
5793  * 'encoding'.
5794  */
5795     static int
5796 need_conversion(char_u *fenc)
5797 {
5798     int		same_encoding;
5799     int		enc_flags;
5800     int		fenc_flags;
5801 
5802     if (*fenc == NUL || STRCMP(p_enc, fenc) == 0)
5803     {
5804 	same_encoding = TRUE;
5805 	fenc_flags = 0;
5806     }
5807     else
5808     {
5809 	/* Ignore difference between "ansi" and "latin1", "ucs-4" and
5810 	 * "ucs-4be", etc. */
5811 	enc_flags = get_fio_flags(p_enc);
5812 	fenc_flags = get_fio_flags(fenc);
5813 	same_encoding = (enc_flags != 0 && fenc_flags == enc_flags);
5814     }
5815     if (same_encoding)
5816     {
5817 	/* Specified encoding matches with 'encoding'.  This requires
5818 	 * conversion when 'encoding' is Unicode but not UTF-8. */
5819 	return enc_unicode != 0;
5820     }
5821 
5822     /* Encodings differ.  However, conversion is not needed when 'enc' is any
5823      * Unicode encoding and the file is UTF-8. */
5824     return !(enc_utf8 && fenc_flags == FIO_UTF8);
5825 }
5826 
5827 /*
5828  * Check "ptr" for a unicode encoding and return the FIO_ flags needed for the
5829  * internal conversion.
5830  * if "ptr" is an empty string, use 'encoding'.
5831  */
5832     static int
5833 get_fio_flags(char_u *ptr)
5834 {
5835     int		prop;
5836 
5837     if (*ptr == NUL)
5838 	ptr = p_enc;
5839 
5840     prop = enc_canon_props(ptr);
5841     if (prop & ENC_UNICODE)
5842     {
5843 	if (prop & ENC_2BYTE)
5844 	{
5845 	    if (prop & ENC_ENDIAN_L)
5846 		return FIO_UCS2 | FIO_ENDIAN_L;
5847 	    return FIO_UCS2;
5848 	}
5849 	if (prop & ENC_4BYTE)
5850 	{
5851 	    if (prop & ENC_ENDIAN_L)
5852 		return FIO_UCS4 | FIO_ENDIAN_L;
5853 	    return FIO_UCS4;
5854 	}
5855 	if (prop & ENC_2WORD)
5856 	{
5857 	    if (prop & ENC_ENDIAN_L)
5858 		return FIO_UTF16 | FIO_ENDIAN_L;
5859 	    return FIO_UTF16;
5860 	}
5861 	return FIO_UTF8;
5862     }
5863     if (prop & ENC_LATIN1)
5864 	return FIO_LATIN1;
5865     /* must be ENC_DBCS, requires iconv() */
5866     return 0;
5867 }
5868 
5869 #ifdef MSWIN
5870 /*
5871  * Check "ptr" for a MS-Windows codepage name and return the FIO_ flags needed
5872  * for the conversion MS-Windows can do for us.  Also accept "utf-8".
5873  * Used for conversion between 'encoding' and 'fileencoding'.
5874  */
5875     static int
5876 get_win_fio_flags(char_u *ptr)
5877 {
5878     int		cp;
5879 
5880     /* Cannot do this when 'encoding' is not utf-8 and not a codepage. */
5881     if (!enc_utf8 && enc_codepage <= 0)
5882 	return 0;
5883 
5884     cp = encname2codepage(ptr);
5885     if (cp == 0)
5886     {
5887 #  ifdef CP_UTF8	/* VC 4.1 doesn't define CP_UTF8 */
5888 	if (STRCMP(ptr, "utf-8") == 0)
5889 	    cp = CP_UTF8;
5890 	else
5891 #  endif
5892 	    return 0;
5893     }
5894     return FIO_PUT_CP(cp) | FIO_CODEPAGE;
5895 }
5896 #endif
5897 
5898 #ifdef MACOS_CONVERT
5899 /*
5900  * Check "ptr" for a Carbon supported encoding and return the FIO_ flags
5901  * needed for the internal conversion to/from utf-8 or latin1.
5902  */
5903     static int
5904 get_mac_fio_flags(char_u *ptr)
5905 {
5906     if ((enc_utf8 || STRCMP(p_enc, "latin1") == 0)
5907 				     && (enc_canon_props(ptr) & ENC_MACROMAN))
5908 	return FIO_MACROMAN;
5909     return 0;
5910 }
5911 #endif
5912 
5913 /*
5914  * Check for a Unicode BOM (Byte Order Mark) at the start of p[size].
5915  * "size" must be at least 2.
5916  * Return the name of the encoding and set "*lenp" to the length.
5917  * Returns NULL when no BOM found.
5918  */
5919     static char_u *
5920 check_for_bom(
5921     char_u	*p,
5922     long	size,
5923     int		*lenp,
5924     int		flags)
5925 {
5926     char	*name = NULL;
5927     int		len = 2;
5928 
5929     if (p[0] == 0xef && p[1] == 0xbb && size >= 3 && p[2] == 0xbf
5930 	    && (flags == FIO_ALL || flags == FIO_UTF8 || flags == 0))
5931     {
5932 	name = "utf-8";		/* EF BB BF */
5933 	len = 3;
5934     }
5935     else if (p[0] == 0xff && p[1] == 0xfe)
5936     {
5937 	if (size >= 4 && p[2] == 0 && p[3] == 0
5938 	    && (flags == FIO_ALL || flags == (FIO_UCS4 | FIO_ENDIAN_L)))
5939 	{
5940 	    name = "ucs-4le";	/* FF FE 00 00 */
5941 	    len = 4;
5942 	}
5943 	else if (flags == (FIO_UCS2 | FIO_ENDIAN_L))
5944 	    name = "ucs-2le";	/* FF FE */
5945 	else if (flags == FIO_ALL || flags == (FIO_UTF16 | FIO_ENDIAN_L))
5946 	    /* utf-16le is preferred, it also works for ucs-2le text */
5947 	    name = "utf-16le";	/* FF FE */
5948     }
5949     else if (p[0] == 0xfe && p[1] == 0xff
5950 	    && (flags == FIO_ALL || flags == FIO_UCS2 || flags == FIO_UTF16))
5951     {
5952 	/* Default to utf-16, it works also for ucs-2 text. */
5953 	if (flags == FIO_UCS2)
5954 	    name = "ucs-2";	/* FE FF */
5955 	else
5956 	    name = "utf-16";	/* FE FF */
5957     }
5958     else if (size >= 4 && p[0] == 0 && p[1] == 0 && p[2] == 0xfe
5959 	    && p[3] == 0xff && (flags == FIO_ALL || flags == FIO_UCS4))
5960     {
5961 	name = "ucs-4";		/* 00 00 FE FF */
5962 	len = 4;
5963     }
5964 
5965     *lenp = len;
5966     return (char_u *)name;
5967 }
5968 
5969 /*
5970  * Generate a BOM in "buf[4]" for encoding "name".
5971  * Return the length of the BOM (zero when no BOM).
5972  */
5973     static int
5974 make_bom(char_u *buf, char_u *name)
5975 {
5976     int		flags;
5977     char_u	*p;
5978 
5979     flags = get_fio_flags(name);
5980 
5981     /* Can't put a BOM in a non-Unicode file. */
5982     if (flags == FIO_LATIN1 || flags == 0)
5983 	return 0;
5984 
5985     if (flags == FIO_UTF8)	/* UTF-8 */
5986     {
5987 	buf[0] = 0xef;
5988 	buf[1] = 0xbb;
5989 	buf[2] = 0xbf;
5990 	return 3;
5991     }
5992     p = buf;
5993     (void)ucs2bytes(0xfeff, &p, flags);
5994     return (int)(p - buf);
5995 }
5996 
5997 /*
5998  * Try to find a shortname by comparing the fullname with the current
5999  * directory.
6000  * Returns "full_path" or pointer into "full_path" if shortened.
6001  */
6002     char_u *
6003 shorten_fname1(char_u *full_path)
6004 {
6005     char_u	*dirname;
6006     char_u	*p = full_path;
6007 
6008     dirname = alloc(MAXPATHL);
6009     if (dirname == NULL)
6010 	return full_path;
6011     if (mch_dirname(dirname, MAXPATHL) == OK)
6012     {
6013 	p = shorten_fname(full_path, dirname);
6014 	if (p == NULL || *p == NUL)
6015 	    p = full_path;
6016     }
6017     vim_free(dirname);
6018     return p;
6019 }
6020 
6021 /*
6022  * Try to find a shortname by comparing the fullname with the current
6023  * directory.
6024  * Returns NULL if not shorter name possible, pointer into "full_path"
6025  * otherwise.
6026  */
6027     char_u *
6028 shorten_fname(char_u *full_path, char_u *dir_name)
6029 {
6030     int		len;
6031     char_u	*p;
6032 
6033     if (full_path == NULL)
6034 	return NULL;
6035     len = (int)STRLEN(dir_name);
6036     if (fnamencmp(dir_name, full_path, len) == 0)
6037     {
6038 	p = full_path + len;
6039 #if defined(MSWIN)
6040 	/*
6041 	 * MS-Windows: when a file is in the root directory, dir_name will end
6042 	 * in a slash, since C: by itself does not define a specific dir. In
6043 	 * this case p may already be correct. <negri>
6044 	 */
6045 	if (!((len > 2) && (*(p - 2) == ':')))
6046 #endif
6047 	{
6048 	    if (vim_ispathsep(*p))
6049 		++p;
6050 #ifndef VMS   /* the path separator is always part of the path */
6051 	    else
6052 		p = NULL;
6053 #endif
6054 	}
6055     }
6056 #if defined(MSWIN)
6057     /*
6058      * When using a file in the current drive, remove the drive name:
6059      * "A:\dir\file" -> "\dir\file".  This helps when moving a session file on
6060      * a floppy from "A:\dir" to "B:\dir".
6061      */
6062     else if (len > 3
6063 	    && TOUPPER_LOC(full_path[0]) == TOUPPER_LOC(dir_name[0])
6064 	    && full_path[1] == ':'
6065 	    && vim_ispathsep(full_path[2]))
6066 	p = full_path + 2;
6067 #endif
6068     else
6069 	p = NULL;
6070     return p;
6071 }
6072 
6073 /*
6074  * Shorten filename of a buffer.
6075  * When "force" is TRUE: Use full path from now on for files currently being
6076  * edited, both for file name and swap file name.  Try to shorten the file
6077  * names a bit, if safe to do so.
6078  * When "force" is FALSE: Only try to shorten absolute file names.
6079  * For buffers that have buftype "nofile" or "scratch": never change the file
6080  * name.
6081  */
6082     void
6083 shorten_buf_fname(buf_T *buf, char_u *dirname, int force)
6084 {
6085     char_u	*p;
6086 
6087     if (buf->b_fname != NULL
6088 #ifdef FEAT_QUICKFIX
6089 	    && !bt_nofile(buf)
6090 #endif
6091 	    && !path_with_url(buf->b_fname)
6092 	    && (force
6093 		|| buf->b_sfname == NULL
6094 		|| mch_isFullName(buf->b_sfname)))
6095     {
6096 	if (buf->b_sfname != buf->b_ffname)
6097 	    VIM_CLEAR(buf->b_sfname);
6098 	p = shorten_fname(buf->b_ffname, dirname);
6099 	if (p != NULL)
6100 	{
6101 	    buf->b_sfname = vim_strsave(p);
6102 	    buf->b_fname = buf->b_sfname;
6103 	}
6104 	if (p == NULL || buf->b_fname == NULL)
6105 	    buf->b_fname = buf->b_ffname;
6106     }
6107 }
6108 
6109 /*
6110  * Shorten filenames for all buffers.
6111  */
6112     void
6113 shorten_fnames(int force)
6114 {
6115     char_u	dirname[MAXPATHL];
6116     buf_T	*buf;
6117 
6118     mch_dirname(dirname, MAXPATHL);
6119     FOR_ALL_BUFFERS(buf)
6120     {
6121 	shorten_buf_fname(buf, dirname, force);
6122 
6123 	/* Always make the swap file name a full path, a "nofile" buffer may
6124 	 * also have a swap file. */
6125 	mf_fullname(buf->b_ml.ml_mfp);
6126     }
6127     status_redraw_all();
6128     redraw_tabline = TRUE;
6129 }
6130 
6131 #if (defined(FEAT_DND) && defined(FEAT_GUI_GTK)) \
6132 	|| defined(FEAT_GUI_MSWIN) \
6133 	|| defined(FEAT_GUI_MAC) \
6134 	|| defined(PROTO)
6135 /*
6136  * Shorten all filenames in "fnames[count]" by current directory.
6137  */
6138     void
6139 shorten_filenames(char_u **fnames, int count)
6140 {
6141     int		i;
6142     char_u	dirname[MAXPATHL];
6143     char_u	*p;
6144 
6145     if (fnames == NULL || count < 1)
6146 	return;
6147     mch_dirname(dirname, sizeof(dirname));
6148     for (i = 0; i < count; ++i)
6149     {
6150 	if ((p = shorten_fname(fnames[i], dirname)) != NULL)
6151 	{
6152 	    /* shorten_fname() returns pointer in given "fnames[i]".  If free
6153 	     * "fnames[i]" first, "p" becomes invalid.  So we need to copy
6154 	     * "p" first then free fnames[i]. */
6155 	    p = vim_strsave(p);
6156 	    vim_free(fnames[i]);
6157 	    fnames[i] = p;
6158 	}
6159     }
6160 }
6161 #endif
6162 
6163 /*
6164  * Add extension to file name - change path/fo.o.h to path/fo.o.h.ext or
6165  * fo_o_h.ext for MSDOS or when shortname option set.
6166  *
6167  * Assumed that fname is a valid name found in the filesystem we assure that
6168  * the return value is a different name and ends in 'ext'.
6169  * "ext" MUST be at most 4 characters long if it starts with a dot, 3
6170  * characters otherwise.
6171  * Space for the returned name is allocated, must be freed later.
6172  * Returns NULL when out of memory.
6173  */
6174     char_u *
6175 modname(
6176     char_u *fname,
6177     char_u *ext,
6178     int	    prepend_dot)	/* may prepend a '.' to file name */
6179 {
6180     return buf_modname((curbuf->b_p_sn || curbuf->b_shortname),
6181 						     fname, ext, prepend_dot);
6182 }
6183 
6184     char_u *
6185 buf_modname(
6186     int	    shortname,		/* use 8.3 file name */
6187     char_u  *fname,
6188     char_u  *ext,
6189     int	    prepend_dot)	/* may prepend a '.' to file name */
6190 {
6191     char_u	*retval;
6192     char_u	*s;
6193     char_u	*e;
6194     char_u	*ptr;
6195     int		fnamelen, extlen;
6196 
6197     extlen = (int)STRLEN(ext);
6198 
6199     /*
6200      * If there is no file name we must get the name of the current directory
6201      * (we need the full path in case :cd is used).
6202      */
6203     if (fname == NULL || *fname == NUL)
6204     {
6205 	retval = alloc((unsigned)(MAXPATHL + extlen + 3));
6206 	if (retval == NULL)
6207 	    return NULL;
6208 	if (mch_dirname(retval, MAXPATHL) == FAIL ||
6209 				     (fnamelen = (int)STRLEN(retval)) == 0)
6210 	{
6211 	    vim_free(retval);
6212 	    return NULL;
6213 	}
6214 	if (!after_pathsep(retval, retval + fnamelen))
6215 	{
6216 	    retval[fnamelen++] = PATHSEP;
6217 	    retval[fnamelen] = NUL;
6218 	}
6219 	prepend_dot = FALSE;	    /* nothing to prepend a dot to */
6220     }
6221     else
6222     {
6223 	fnamelen = (int)STRLEN(fname);
6224 	retval = alloc((unsigned)(fnamelen + extlen + 3));
6225 	if (retval == NULL)
6226 	    return NULL;
6227 	STRCPY(retval, fname);
6228 #ifdef VMS
6229 	vms_remove_version(retval); /* we do not need versions here */
6230 #endif
6231     }
6232 
6233     /*
6234      * search backwards until we hit a '/', '\' or ':' replacing all '.'
6235      * by '_' for MSDOS or when shortname option set and ext starts with a dot.
6236      * Then truncate what is after the '/', '\' or ':' to 8 characters for
6237      * MSDOS and 26 characters for AMIGA, a lot more for UNIX.
6238      */
6239     for (ptr = retval + fnamelen; ptr > retval; MB_PTR_BACK(retval, ptr))
6240     {
6241 	if (*ext == '.' && shortname)
6242 	    if (*ptr == '.')	/* replace '.' by '_' */
6243 		*ptr = '_';
6244 	if (vim_ispathsep(*ptr))
6245 	{
6246 	    ++ptr;
6247 	    break;
6248 	}
6249     }
6250 
6251     /* the file name has at most BASENAMELEN characters. */
6252     if (STRLEN(ptr) > (unsigned)BASENAMELEN)
6253 	ptr[BASENAMELEN] = '\0';
6254 
6255     s = ptr + STRLEN(ptr);
6256 
6257     /*
6258      * For 8.3 file names we may have to reduce the length.
6259      */
6260     if (shortname)
6261     {
6262 	/*
6263 	 * If there is no file name, or the file name ends in '/', and the
6264 	 * extension starts with '.', put a '_' before the dot, because just
6265 	 * ".ext" is invalid.
6266 	 */
6267 	if (fname == NULL || *fname == NUL
6268 				   || vim_ispathsep(fname[STRLEN(fname) - 1]))
6269 	{
6270 	    if (*ext == '.')
6271 		*s++ = '_';
6272 	}
6273 	/*
6274 	 * If the extension starts with '.', truncate the base name at 8
6275 	 * characters
6276 	 */
6277 	else if (*ext == '.')
6278 	{
6279 	    if ((size_t)(s - ptr) > (size_t)8)
6280 	    {
6281 		s = ptr + 8;
6282 		*s = '\0';
6283 	    }
6284 	}
6285 	/*
6286 	 * If the extension doesn't start with '.', and the file name
6287 	 * doesn't have an extension yet, append a '.'
6288 	 */
6289 	else if ((e = vim_strchr(ptr, '.')) == NULL)
6290 	    *s++ = '.';
6291 	/*
6292 	 * If the extension doesn't start with '.', and there already is an
6293 	 * extension, it may need to be truncated
6294 	 */
6295 	else if ((int)STRLEN(e) + extlen > 4)
6296 	    s = e + 4 - extlen;
6297     }
6298 #ifdef MSWIN
6299     /*
6300      * If there is no file name, and the extension starts with '.', put a
6301      * '_' before the dot, because just ".ext" may be invalid if it's on a
6302      * FAT partition, and on HPFS it doesn't matter.
6303      */
6304     else if ((fname == NULL || *fname == NUL) && *ext == '.')
6305 	*s++ = '_';
6306 #endif
6307 
6308     /*
6309      * Append the extension.
6310      * ext can start with '.' and cannot exceed 3 more characters.
6311      */
6312     STRCPY(s, ext);
6313 
6314     /*
6315      * Prepend the dot.
6316      */
6317     if (prepend_dot && !shortname && *(e = gettail(retval)) != '.')
6318     {
6319 	STRMOVE(e + 1, e);
6320 	*e = '.';
6321     }
6322 
6323     /*
6324      * Check that, after appending the extension, the file name is really
6325      * different.
6326      */
6327     if (fname != NULL && STRCMP(fname, retval) == 0)
6328     {
6329 	/* we search for a character that can be replaced by '_' */
6330 	while (--s >= ptr)
6331 	{
6332 	    if (*s != '_')
6333 	    {
6334 		*s = '_';
6335 		break;
6336 	    }
6337 	}
6338 	if (s < ptr)	/* fname was "________.<ext>", how tricky! */
6339 	    *ptr = 'v';
6340     }
6341     return retval;
6342 }
6343 
6344 /*
6345  * Like fgets(), but if the file line is too long, it is truncated and the
6346  * rest of the line is thrown away.  Returns TRUE for end-of-file.
6347  * If the line is truncated then buf[size - 2] will not be NUL.
6348  */
6349     int
6350 vim_fgets(char_u *buf, int size, FILE *fp)
6351 {
6352     char	*eof;
6353 #define FGETS_SIZE 200
6354     char	tbuf[FGETS_SIZE];
6355 
6356     buf[size - 2] = NUL;
6357     eof = fgets((char *)buf, size, fp);
6358     if (buf[size - 2] != NUL && buf[size - 2] != '\n')
6359     {
6360 	buf[size - 1] = NUL;	    /* Truncate the line */
6361 
6362 	/* Now throw away the rest of the line: */
6363 	do
6364 	{
6365 	    tbuf[FGETS_SIZE - 2] = NUL;
6366 	    vim_ignoredp = fgets((char *)tbuf, FGETS_SIZE, fp);
6367 	} while (tbuf[FGETS_SIZE - 2] != NUL && tbuf[FGETS_SIZE - 2] != '\n');
6368     }
6369     return (eof == NULL);
6370 }
6371 
6372 /*
6373  * rename() only works if both files are on the same file system, this
6374  * function will (attempts to?) copy the file across if rename fails -- webb
6375  * Return -1 for failure, 0 for success.
6376  */
6377     int
6378 vim_rename(char_u *from, char_u *to)
6379 {
6380     int		fd_in;
6381     int		fd_out;
6382     int		n;
6383     char	*errmsg = NULL;
6384     char	*buffer;
6385 #ifdef AMIGA
6386     BPTR	flock;
6387 #endif
6388     stat_T	st;
6389     long	perm;
6390 #ifdef HAVE_ACL
6391     vim_acl_T	acl;		/* ACL from original file */
6392 #endif
6393     int		use_tmp_file = FALSE;
6394 
6395     /*
6396      * When the names are identical, there is nothing to do.  When they refer
6397      * to the same file (ignoring case and slash/backslash differences) but
6398      * the file name differs we need to go through a temp file.
6399      */
6400     if (fnamecmp(from, to) == 0)
6401     {
6402 	if (p_fic && STRCMP(gettail(from), gettail(to)) != 0)
6403 	    use_tmp_file = TRUE;
6404 	else
6405 	    return 0;
6406     }
6407 
6408     /*
6409      * Fail if the "from" file doesn't exist.  Avoids that "to" is deleted.
6410      */
6411     if (mch_stat((char *)from, &st) < 0)
6412 	return -1;
6413 
6414 #ifdef UNIX
6415     {
6416 	stat_T	st_to;
6417 
6418 	/* It's possible for the source and destination to be the same file.
6419 	 * This happens when "from" and "to" differ in case and are on a FAT32
6420 	 * filesystem.  In that case go through a temp file name. */
6421 	if (mch_stat((char *)to, &st_to) >= 0
6422 		&& st.st_dev == st_to.st_dev
6423 		&& st.st_ino == st_to.st_ino)
6424 	    use_tmp_file = TRUE;
6425     }
6426 #endif
6427 #ifdef MSWIN
6428     {
6429 	BY_HANDLE_FILE_INFORMATION info1, info2;
6430 
6431 	/* It's possible for the source and destination to be the same file.
6432 	 * In that case go through a temp file name.  This makes rename("foo",
6433 	 * "./foo") a no-op (in a complicated way). */
6434 	if (win32_fileinfo(from, &info1) == FILEINFO_OK
6435 		&& win32_fileinfo(to, &info2) == FILEINFO_OK
6436 		&& info1.dwVolumeSerialNumber == info2.dwVolumeSerialNumber
6437 		&& info1.nFileIndexHigh == info2.nFileIndexHigh
6438 		&& info1.nFileIndexLow == info2.nFileIndexLow)
6439 	    use_tmp_file = TRUE;
6440     }
6441 #endif
6442 
6443     if (use_tmp_file)
6444     {
6445 	char	tempname[MAXPATHL + 1];
6446 
6447 	/*
6448 	 * Find a name that doesn't exist and is in the same directory.
6449 	 * Rename "from" to "tempname" and then rename "tempname" to "to".
6450 	 */
6451 	if (STRLEN(from) >= MAXPATHL - 5)
6452 	    return -1;
6453 	STRCPY(tempname, from);
6454 	for (n = 123; n < 99999; ++n)
6455 	{
6456 	    sprintf((char *)gettail((char_u *)tempname), "%d", n);
6457 	    if (mch_stat(tempname, &st) < 0)
6458 	    {
6459 		if (mch_rename((char *)from, tempname) == 0)
6460 		{
6461 		    if (mch_rename(tempname, (char *)to) == 0)
6462 			return 0;
6463 		    /* Strange, the second step failed.  Try moving the
6464 		     * file back and return failure. */
6465 		    mch_rename(tempname, (char *)from);
6466 		    return -1;
6467 		}
6468 		/* If it fails for one temp name it will most likely fail
6469 		 * for any temp name, give up. */
6470 		return -1;
6471 	    }
6472 	}
6473 	return -1;
6474     }
6475 
6476     /*
6477      * Delete the "to" file, this is required on some systems to make the
6478      * mch_rename() work, on other systems it makes sure that we don't have
6479      * two files when the mch_rename() fails.
6480      */
6481 
6482 #ifdef AMIGA
6483     /*
6484      * With MSDOS-compatible filesystems (crossdos, messydos) it is possible
6485      * that the name of the "to" file is the same as the "from" file, even
6486      * though the names are different. To avoid the chance of accidentally
6487      * deleting the "from" file (horror!) we lock it during the remove.
6488      *
6489      * When used for making a backup before writing the file: This should not
6490      * happen with ":w", because startscript() should detect this problem and
6491      * set buf->b_shortname, causing modname() to return a correct ".bak" file
6492      * name.  This problem does exist with ":w filename", but then the
6493      * original file will be somewhere else so the backup isn't really
6494      * important. If autoscripting is off the rename may fail.
6495      */
6496     flock = Lock((UBYTE *)from, (long)ACCESS_READ);
6497 #endif
6498     mch_remove(to);
6499 #ifdef AMIGA
6500     if (flock)
6501 	UnLock(flock);
6502 #endif
6503 
6504     /*
6505      * First try a normal rename, return if it works.
6506      */
6507     if (mch_rename((char *)from, (char *)to) == 0)
6508 	return 0;
6509 
6510     /*
6511      * Rename() failed, try copying the file.
6512      */
6513     perm = mch_getperm(from);
6514 #ifdef HAVE_ACL
6515     /* For systems that support ACL: get the ACL from the original file. */
6516     acl = mch_get_acl(from);
6517 #endif
6518     fd_in = mch_open((char *)from, O_RDONLY|O_EXTRA, 0);
6519     if (fd_in == -1)
6520     {
6521 #ifdef HAVE_ACL
6522 	mch_free_acl(acl);
6523 #endif
6524 	return -1;
6525     }
6526 
6527     /* Create the new file with same permissions as the original. */
6528     fd_out = mch_open((char *)to,
6529 		       O_CREAT|O_EXCL|O_WRONLY|O_EXTRA|O_NOFOLLOW, (int)perm);
6530     if (fd_out == -1)
6531     {
6532 	close(fd_in);
6533 #ifdef HAVE_ACL
6534 	mch_free_acl(acl);
6535 #endif
6536 	return -1;
6537     }
6538 
6539     buffer = (char *)alloc(BUFSIZE);
6540     if (buffer == NULL)
6541     {
6542 	close(fd_out);
6543 	close(fd_in);
6544 #ifdef HAVE_ACL
6545 	mch_free_acl(acl);
6546 #endif
6547 	return -1;
6548     }
6549 
6550     while ((n = read_eintr(fd_in, buffer, BUFSIZE)) > 0)
6551 	if (write_eintr(fd_out, buffer, n) != n)
6552 	{
6553 	    errmsg = _("E208: Error writing to \"%s\"");
6554 	    break;
6555 	}
6556 
6557     vim_free(buffer);
6558     close(fd_in);
6559     if (close(fd_out) < 0)
6560 	errmsg = _("E209: Error closing \"%s\"");
6561     if (n < 0)
6562     {
6563 	errmsg = _("E210: Error reading \"%s\"");
6564 	to = from;
6565     }
6566 #ifndef UNIX	    /* for Unix mch_open() already set the permission */
6567     mch_setperm(to, perm);
6568 #endif
6569 #ifdef HAVE_ACL
6570     mch_set_acl(to, acl);
6571     mch_free_acl(acl);
6572 #endif
6573 #if defined(HAVE_SELINUX) || defined(HAVE_SMACK)
6574     mch_copy_sec(from, to);
6575 #endif
6576     if (errmsg != NULL)
6577     {
6578 	semsg(errmsg, to);
6579 	return -1;
6580     }
6581     mch_remove(from);
6582     return 0;
6583 }
6584 
6585 static int already_warned = FALSE;
6586 
6587 /*
6588  * Check if any not hidden buffer has been changed.
6589  * Postpone the check if there are characters in the stuff buffer, a global
6590  * command is being executed, a mapping is being executed or an autocommand is
6591  * busy.
6592  * Returns TRUE if some message was written (screen should be redrawn and
6593  * cursor positioned).
6594  */
6595     int
6596 check_timestamps(
6597     int		focus)		/* called for GUI focus event */
6598 {
6599     buf_T	*buf;
6600     int		didit = 0;
6601     int		n;
6602 
6603     /* Don't check timestamps while system() or another low-level function may
6604      * cause us to lose and gain focus. */
6605     if (no_check_timestamps > 0)
6606 	return FALSE;
6607 
6608     /* Avoid doing a check twice.  The OK/Reload dialog can cause a focus
6609      * event and we would keep on checking if the file is steadily growing.
6610      * Do check again after typing something. */
6611     if (focus && did_check_timestamps)
6612     {
6613 	need_check_timestamps = TRUE;
6614 	return FALSE;
6615     }
6616 
6617     if (!stuff_empty() || global_busy || !typebuf_typed()
6618 			|| autocmd_busy || curbuf_lock > 0 || allbuf_lock > 0)
6619 	need_check_timestamps = TRUE;		/* check later */
6620     else
6621     {
6622 	++no_wait_return;
6623 	did_check_timestamps = TRUE;
6624 	already_warned = FALSE;
6625 	FOR_ALL_BUFFERS(buf)
6626 	{
6627 	    /* Only check buffers in a window. */
6628 	    if (buf->b_nwindows > 0)
6629 	    {
6630 		bufref_T bufref;
6631 
6632 		set_bufref(&bufref, buf);
6633 		n = buf_check_timestamp(buf, focus);
6634 		if (didit < n)
6635 		    didit = n;
6636 		if (n > 0 && !bufref_valid(&bufref))
6637 		{
6638 		    /* Autocommands have removed the buffer, start at the
6639 		     * first one again. */
6640 		    buf = firstbuf;
6641 		    continue;
6642 		}
6643 	    }
6644 	}
6645 	--no_wait_return;
6646 	need_check_timestamps = FALSE;
6647 	if (need_wait_return && didit == 2)
6648 	{
6649 	    /* make sure msg isn't overwritten */
6650 	    msg_puts("\n");
6651 	    out_flush();
6652 	}
6653     }
6654     return didit;
6655 }
6656 
6657 /*
6658  * Move all the lines from buffer "frombuf" to buffer "tobuf".
6659  * Return OK or FAIL.  When FAIL "tobuf" is incomplete and/or "frombuf" is not
6660  * empty.
6661  */
6662     static int
6663 move_lines(buf_T *frombuf, buf_T *tobuf)
6664 {
6665     buf_T	*tbuf = curbuf;
6666     int		retval = OK;
6667     linenr_T	lnum;
6668     char_u	*p;
6669 
6670     /* Copy the lines in "frombuf" to "tobuf". */
6671     curbuf = tobuf;
6672     for (lnum = 1; lnum <= frombuf->b_ml.ml_line_count; ++lnum)
6673     {
6674 	p = vim_strsave(ml_get_buf(frombuf, lnum, FALSE));
6675 	if (p == NULL || ml_append(lnum - 1, p, 0, FALSE) == FAIL)
6676 	{
6677 	    vim_free(p);
6678 	    retval = FAIL;
6679 	    break;
6680 	}
6681 	vim_free(p);
6682     }
6683 
6684     /* Delete all the lines in "frombuf". */
6685     if (retval != FAIL)
6686     {
6687 	curbuf = frombuf;
6688 	for (lnum = curbuf->b_ml.ml_line_count; lnum > 0; --lnum)
6689 	    if (ml_delete(lnum, FALSE) == FAIL)
6690 	    {
6691 		/* Oops!  We could try putting back the saved lines, but that
6692 		 * might fail again... */
6693 		retval = FAIL;
6694 		break;
6695 	    }
6696     }
6697 
6698     curbuf = tbuf;
6699     return retval;
6700 }
6701 
6702 /*
6703  * Check if buffer "buf" has been changed.
6704  * Also check if the file for a new buffer unexpectedly appeared.
6705  * return 1 if a changed buffer was found.
6706  * return 2 if a message has been displayed.
6707  * return 0 otherwise.
6708  */
6709     int
6710 buf_check_timestamp(
6711     buf_T	*buf,
6712     int		focus UNUSED)	/* called for GUI focus event */
6713 {
6714     stat_T	st;
6715     int		stat_res;
6716     int		retval = 0;
6717     char_u	*path;
6718     char	*tbuf;
6719     char	*mesg = NULL;
6720     char	*mesg2 = "";
6721     int		helpmesg = FALSE;
6722     int		reload = FALSE;
6723     char	*reason;
6724 #if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
6725     int		can_reload = FALSE;
6726 #endif
6727     off_T	orig_size = buf->b_orig_size;
6728     int		orig_mode = buf->b_orig_mode;
6729 #ifdef FEAT_GUI
6730     int		save_mouse_correct = need_mouse_correct;
6731 #endif
6732     static int	busy = FALSE;
6733     int		n;
6734 #ifdef FEAT_EVAL
6735     char_u	*s;
6736 #endif
6737     bufref_T	bufref;
6738 
6739     set_bufref(&bufref, buf);
6740 
6741     /* If there is no file name, the buffer is not loaded, 'buftype' is
6742      * set, we are in the middle of a save or being called recursively: ignore
6743      * this buffer. */
6744     if (buf->b_ffname == NULL
6745 	    || buf->b_ml.ml_mfp == NULL
6746 	    || !bt_normal(buf)
6747 	    || buf->b_saving
6748 	    || busy
6749 #ifdef FEAT_NETBEANS_INTG
6750 	    || isNetbeansBuffer(buf)
6751 #endif
6752 #ifdef FEAT_TERMINAL
6753 	    || buf->b_term != NULL
6754 #endif
6755 	    )
6756 	return 0;
6757 
6758     if (       !(buf->b_flags & BF_NOTEDITED)
6759 	    && buf->b_mtime != 0
6760 	    && ((stat_res = mch_stat((char *)buf->b_ffname, &st)) < 0
6761 		|| time_differs((long)st.st_mtime, buf->b_mtime)
6762 		|| st.st_size != buf->b_orig_size
6763 #ifdef HAVE_ST_MODE
6764 		|| (int)st.st_mode != buf->b_orig_mode
6765 #else
6766 		|| mch_getperm(buf->b_ffname) != buf->b_orig_mode
6767 #endif
6768 		))
6769     {
6770 	retval = 1;
6771 
6772 	// set b_mtime to stop further warnings (e.g., when executing
6773 	// FileChangedShell autocmd)
6774 	if (stat_res < 0)
6775 	{
6776 	    // When 'autoread' is set we'll check the file again to see if it
6777 	    // re-appears.
6778 	    buf->b_mtime = buf->b_p_ar;
6779 	    buf->b_orig_size = 0;
6780 	    buf->b_orig_mode = 0;
6781 	}
6782 	else
6783 	    buf_store_time(buf, &st, buf->b_ffname);
6784 
6785 	/* Don't do anything for a directory.  Might contain the file
6786 	 * explorer. */
6787 	if (mch_isdir(buf->b_fname))
6788 	    ;
6789 
6790 	/*
6791 	 * If 'autoread' is set, the buffer has no changes and the file still
6792 	 * exists, reload the buffer.  Use the buffer-local option value if it
6793 	 * was set, the global option value otherwise.
6794 	 */
6795 	else if ((buf->b_p_ar >= 0 ? buf->b_p_ar : p_ar)
6796 				       && !bufIsChanged(buf) && stat_res >= 0)
6797 	    reload = TRUE;
6798 	else
6799 	{
6800 	    if (stat_res < 0)
6801 		reason = "deleted";
6802 	    else if (bufIsChanged(buf))
6803 		reason = "conflict";
6804 	    /*
6805 	     * Check if the file contents really changed to avoid giving a
6806 	     * warning when only the timestamp was set (e.g., checked out of
6807 	     * CVS).  Always warn when the buffer was changed.
6808 	     */
6809 	    else if (orig_size != buf->b_orig_size || buf_contents_changed(buf))
6810 		reason = "changed";
6811 	    else if (orig_mode != buf->b_orig_mode)
6812 		reason = "mode";
6813 	    else
6814 		reason = "time";
6815 
6816 	    /*
6817 	     * Only give the warning if there are no FileChangedShell
6818 	     * autocommands.
6819 	     * Avoid being called recursively by setting "busy".
6820 	     */
6821 	    busy = TRUE;
6822 #ifdef FEAT_EVAL
6823 	    set_vim_var_string(VV_FCS_REASON, (char_u *)reason, -1);
6824 	    set_vim_var_string(VV_FCS_CHOICE, (char_u *)"", -1);
6825 #endif
6826 	    ++allbuf_lock;
6827 	    n = apply_autocmds(EVENT_FILECHANGEDSHELL,
6828 				      buf->b_fname, buf->b_fname, FALSE, buf);
6829 	    --allbuf_lock;
6830 	    busy = FALSE;
6831 	    if (n)
6832 	    {
6833 		if (!bufref_valid(&bufref))
6834 		    emsg(_("E246: FileChangedShell autocommand deleted buffer"));
6835 #ifdef FEAT_EVAL
6836 		s = get_vim_var_str(VV_FCS_CHOICE);
6837 		if (STRCMP(s, "reload") == 0 && *reason != 'd')
6838 		    reload = TRUE;
6839 		else if (STRCMP(s, "ask") == 0)
6840 		    n = FALSE;
6841 		else
6842 #endif
6843 		    return 2;
6844 	    }
6845 	    if (!n)
6846 	    {
6847 		if (*reason == 'd')
6848 		    mesg = _("E211: File \"%s\" no longer available");
6849 		else
6850 		{
6851 		    helpmesg = TRUE;
6852 #if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
6853 		    can_reload = TRUE;
6854 #endif
6855 		    if (reason[2] == 'n')
6856 		    {
6857 			mesg = _("W12: Warning: File \"%s\" has changed and the buffer was changed in Vim as well");
6858 			mesg2 = _("See \":help W12\" for more info.");
6859 		    }
6860 		    else if (reason[1] == 'h')
6861 		    {
6862 			mesg = _("W11: Warning: File \"%s\" has changed since editing started");
6863 			mesg2 = _("See \":help W11\" for more info.");
6864 		    }
6865 		    else if (*reason == 'm')
6866 		    {
6867 			mesg = _("W16: Warning: Mode of file \"%s\" has changed since editing started");
6868 			mesg2 = _("See \":help W16\" for more info.");
6869 		    }
6870 		    else
6871 			/* Only timestamp changed, store it to avoid a warning
6872 			 * in check_mtime() later. */
6873 			buf->b_mtime_read = buf->b_mtime;
6874 		}
6875 	    }
6876 	}
6877 
6878     }
6879     else if ((buf->b_flags & BF_NEW) && !(buf->b_flags & BF_NEW_W)
6880 						&& vim_fexists(buf->b_ffname))
6881     {
6882 	retval = 1;
6883 	mesg = _("W13: Warning: File \"%s\" has been created after editing started");
6884 	buf->b_flags |= BF_NEW_W;
6885 #if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
6886 	can_reload = TRUE;
6887 #endif
6888     }
6889 
6890     if (mesg != NULL)
6891     {
6892 	path = home_replace_save(buf, buf->b_fname);
6893 	if (path != NULL)
6894 	{
6895 	    if (!helpmesg)
6896 		mesg2 = "";
6897 	    tbuf = (char *)alloc((unsigned)(STRLEN(path) + STRLEN(mesg)
6898 							+ STRLEN(mesg2) + 2));
6899 	    sprintf(tbuf, mesg, path);
6900 #ifdef FEAT_EVAL
6901 	    /* Set warningmsg here, before the unimportant and output-specific
6902 	     * mesg2 has been appended. */
6903 	    set_vim_var_string(VV_WARNINGMSG, (char_u *)tbuf, -1);
6904 #endif
6905 #if defined(FEAT_CON_DIALOG) || defined(FEAT_GUI_DIALOG)
6906 	    if (can_reload)
6907 	    {
6908 		if (*mesg2 != NUL)
6909 		{
6910 		    STRCAT(tbuf, "\n");
6911 		    STRCAT(tbuf, mesg2);
6912 		}
6913 		if (do_dialog(VIM_WARNING, (char_u *)_("Warning"),
6914 			    (char_u *)tbuf,
6915 			  (char_u *)_("&OK\n&Load File"), 1, NULL, TRUE) == 2)
6916 		    reload = TRUE;
6917 	    }
6918 	    else
6919 #endif
6920 	    if (State > NORMAL_BUSY || (State & CMDLINE) || already_warned)
6921 	    {
6922 		if (*mesg2 != NUL)
6923 		{
6924 		    STRCAT(tbuf, "; ");
6925 		    STRCAT(tbuf, mesg2);
6926 		}
6927 		emsg(tbuf);
6928 		retval = 2;
6929 	    }
6930 	    else
6931 	    {
6932 		if (!autocmd_busy)
6933 		{
6934 		    msg_start();
6935 		    msg_puts_attr(tbuf, HL_ATTR(HLF_E) + MSG_HIST);
6936 		    if (*mesg2 != NUL)
6937 			msg_puts_attr(mesg2, HL_ATTR(HLF_W) + MSG_HIST);
6938 		    msg_clr_eos();
6939 		    (void)msg_end();
6940 		    if (emsg_silent == 0)
6941 		    {
6942 			out_flush();
6943 #ifdef FEAT_GUI
6944 			if (!focus)
6945 #endif
6946 			    /* give the user some time to think about it */
6947 			    ui_delay(1000L, TRUE);
6948 
6949 			/* don't redraw and erase the message */
6950 			redraw_cmdline = FALSE;
6951 		    }
6952 		}
6953 		already_warned = TRUE;
6954 	    }
6955 
6956 	    vim_free(path);
6957 	    vim_free(tbuf);
6958 	}
6959     }
6960 
6961     if (reload)
6962     {
6963 	/* Reload the buffer. */
6964 	buf_reload(buf, orig_mode);
6965 #ifdef FEAT_PERSISTENT_UNDO
6966 	if (buf->b_p_udf && buf->b_ffname != NULL)
6967 	{
6968 	    char_u	    hash[UNDO_HASH_SIZE];
6969 	    buf_T	    *save_curbuf = curbuf;
6970 
6971 	    /* Any existing undo file is unusable, write it now. */
6972 	    curbuf = buf;
6973 	    u_compute_hash(hash);
6974 	    u_write_undo(NULL, FALSE, buf, hash);
6975 	    curbuf = save_curbuf;
6976 	}
6977 #endif
6978     }
6979 
6980     /* Trigger FileChangedShell when the file was changed in any way. */
6981     if (bufref_valid(&bufref) && retval != 0)
6982 	(void)apply_autocmds(EVENT_FILECHANGEDSHELLPOST,
6983 				      buf->b_fname, buf->b_fname, FALSE, buf);
6984 #ifdef FEAT_GUI
6985     /* restore this in case an autocommand has set it; it would break
6986      * 'mousefocus' */
6987     need_mouse_correct = save_mouse_correct;
6988 #endif
6989 
6990     return retval;
6991 }
6992 
6993 /*
6994  * Reload a buffer that is already loaded.
6995  * Used when the file was changed outside of Vim.
6996  * "orig_mode" is buf->b_orig_mode before the need for reloading was detected.
6997  * buf->b_orig_mode may have been reset already.
6998  */
6999     void
7000 buf_reload(buf_T *buf, int orig_mode)
7001 {
7002     exarg_T	ea;
7003     pos_T	old_cursor;
7004     linenr_T	old_topline;
7005     int		old_ro = buf->b_p_ro;
7006     buf_T	*savebuf;
7007     bufref_T	bufref;
7008     int		saved = OK;
7009     aco_save_T	aco;
7010     int		flags = READ_NEW;
7011 
7012     /* set curwin/curbuf for "buf" and save some things */
7013     aucmd_prepbuf(&aco, buf);
7014 
7015     /* We only want to read the text from the file, not reset the syntax
7016      * highlighting, clear marks, diff status, etc.  Force the fileformat
7017      * and encoding to be the same. */
7018     if (prep_exarg(&ea, buf) == OK)
7019     {
7020 	old_cursor = curwin->w_cursor;
7021 	old_topline = curwin->w_topline;
7022 
7023 	if (p_ur < 0 || curbuf->b_ml.ml_line_count <= p_ur)
7024 	{
7025 	    /* Save all the text, so that the reload can be undone.
7026 	     * Sync first so that this is a separate undo-able action. */
7027 	    u_sync(FALSE);
7028 	    saved = u_savecommon(0, curbuf->b_ml.ml_line_count + 1, 0, TRUE);
7029 	    flags |= READ_KEEP_UNDO;
7030 	}
7031 
7032 	/*
7033 	 * To behave like when a new file is edited (matters for
7034 	 * BufReadPost autocommands) we first need to delete the current
7035 	 * buffer contents.  But if reading the file fails we should keep
7036 	 * the old contents.  Can't use memory only, the file might be
7037 	 * too big.  Use a hidden buffer to move the buffer contents to.
7038 	 */
7039 	if (BUFEMPTY() || saved == FAIL)
7040 	    savebuf = NULL;
7041 	else
7042 	{
7043 	    /* Allocate a buffer without putting it in the buffer list. */
7044 	    savebuf = buflist_new(NULL, NULL, (linenr_T)1, BLN_DUMMY);
7045 	    set_bufref(&bufref, savebuf);
7046 	    if (savebuf != NULL && buf == curbuf)
7047 	    {
7048 		/* Open the memline. */
7049 		curbuf = savebuf;
7050 		curwin->w_buffer = savebuf;
7051 		saved = ml_open(curbuf);
7052 		curbuf = buf;
7053 		curwin->w_buffer = buf;
7054 	    }
7055 	    if (savebuf == NULL || saved == FAIL || buf != curbuf
7056 				      || move_lines(buf, savebuf) == FAIL)
7057 	    {
7058 		semsg(_("E462: Could not prepare for reloading \"%s\""),
7059 							    buf->b_fname);
7060 		saved = FAIL;
7061 	    }
7062 	}
7063 
7064 	if (saved == OK)
7065 	{
7066 	    curbuf->b_flags |= BF_CHECK_RO;	/* check for RO again */
7067 	    keep_filetype = TRUE;		/* don't detect 'filetype' */
7068 	    if (readfile(buf->b_ffname, buf->b_fname, (linenr_T)0,
7069 			(linenr_T)0,
7070 			(linenr_T)MAXLNUM, &ea, flags) != OK)
7071 	    {
7072 #if defined(FEAT_EVAL)
7073 		if (!aborting())
7074 #endif
7075 		    semsg(_("E321: Could not reload \"%s\""), buf->b_fname);
7076 		if (savebuf != NULL && bufref_valid(&bufref) && buf == curbuf)
7077 		{
7078 		    /* Put the text back from the save buffer.  First
7079 		     * delete any lines that readfile() added. */
7080 		    while (!BUFEMPTY())
7081 			if (ml_delete(buf->b_ml.ml_line_count, FALSE) == FAIL)
7082 			    break;
7083 		    (void)move_lines(savebuf, buf);
7084 		}
7085 	    }
7086 	    else if (buf == curbuf)  /* "buf" still valid */
7087 	    {
7088 		/* Mark the buffer as unmodified and free undo info. */
7089 		unchanged(buf, TRUE);
7090 		if ((flags & READ_KEEP_UNDO) == 0)
7091 		{
7092 		    u_blockfree(buf);
7093 		    u_clearall(buf);
7094 		}
7095 		else
7096 		{
7097 		    /* Mark all undo states as changed. */
7098 		    u_unchanged(curbuf);
7099 		}
7100 	    }
7101 	}
7102 	vim_free(ea.cmd);
7103 
7104 	if (savebuf != NULL && bufref_valid(&bufref))
7105 	    wipe_buffer(savebuf, FALSE);
7106 
7107 #ifdef FEAT_DIFF
7108 	/* Invalidate diff info if necessary. */
7109 	diff_invalidate(curbuf);
7110 #endif
7111 
7112 	/* Restore the topline and cursor position and check it (lines may
7113 	 * have been removed). */
7114 	if (old_topline > curbuf->b_ml.ml_line_count)
7115 	    curwin->w_topline = curbuf->b_ml.ml_line_count;
7116 	else
7117 	    curwin->w_topline = old_topline;
7118 	curwin->w_cursor = old_cursor;
7119 	check_cursor();
7120 	update_topline();
7121 	keep_filetype = FALSE;
7122 #ifdef FEAT_FOLDING
7123 	{
7124 	    win_T	*wp;
7125 	    tabpage_T	*tp;
7126 
7127 	    /* Update folds unless they are defined manually. */
7128 	    FOR_ALL_TAB_WINDOWS(tp, wp)
7129 		if (wp->w_buffer == curwin->w_buffer
7130 			&& !foldmethodIsManual(wp))
7131 		    foldUpdateAll(wp);
7132 	}
7133 #endif
7134 	/* If the mode didn't change and 'readonly' was set, keep the old
7135 	 * value; the user probably used the ":view" command.  But don't
7136 	 * reset it, might have had a read error. */
7137 	if (orig_mode == curbuf->b_orig_mode)
7138 	    curbuf->b_p_ro |= old_ro;
7139 
7140 	/* Modelines must override settings done by autocommands. */
7141 	do_modelines(0);
7142     }
7143 
7144     /* restore curwin/curbuf and a few other things */
7145     aucmd_restbuf(&aco);
7146     /* Careful: autocommands may have made "buf" invalid! */
7147 }
7148 
7149     void
7150 buf_store_time(buf_T *buf, stat_T *st, char_u *fname UNUSED)
7151 {
7152     buf->b_mtime = (long)st->st_mtime;
7153     buf->b_orig_size = st->st_size;
7154 #ifdef HAVE_ST_MODE
7155     buf->b_orig_mode = (int)st->st_mode;
7156 #else
7157     buf->b_orig_mode = mch_getperm(fname);
7158 #endif
7159 }
7160 
7161 /*
7162  * Adjust the line with missing eol, used for the next write.
7163  * Used for do_filter(), when the input lines for the filter are deleted.
7164  */
7165     void
7166 write_lnum_adjust(linenr_T offset)
7167 {
7168     if (curbuf->b_no_eol_lnum != 0)	/* only if there is a missing eol */
7169 	curbuf->b_no_eol_lnum += offset;
7170 }
7171 
7172 #if defined(TEMPDIRNAMES) || defined(FEAT_EVAL) || defined(PROTO)
7173 /*
7174  * Delete "name" and everything in it, recursively.
7175  * return 0 for succes, -1 if some file was not deleted.
7176  */
7177     int
7178 delete_recursive(char_u *name)
7179 {
7180     int result = 0;
7181     char_u	**files;
7182     int		file_count;
7183     int		i;
7184     char_u	*exp;
7185 
7186     /* A symbolic link to a directory itself is deleted, not the directory it
7187      * points to. */
7188     if (
7189 # if defined(UNIX) || defined(MSWIN)
7190 	 mch_isrealdir(name)
7191 # else
7192 	 mch_isdir(name)
7193 # endif
7194 	    )
7195     {
7196 	vim_snprintf((char *)NameBuff, MAXPATHL, "%s/*", name);
7197 	exp = vim_strsave(NameBuff);
7198 	if (exp == NULL)
7199 	    return -1;
7200 	if (gen_expand_wildcards(1, &exp, &file_count, &files,
7201 	      EW_DIR|EW_FILE|EW_SILENT|EW_ALLLINKS|EW_DODOT|EW_EMPTYOK) == OK)
7202 	{
7203 	    for (i = 0; i < file_count; ++i)
7204 		if (delete_recursive(files[i]) != 0)
7205 		    result = -1;
7206 	    FreeWild(file_count, files);
7207 	}
7208 	else
7209 	    result = -1;
7210 	vim_free(exp);
7211 	(void)mch_rmdir(name);
7212     }
7213     else
7214 	result = mch_remove(name) == 0 ? 0 : -1;
7215 
7216     return result;
7217 }
7218 #endif
7219 
7220 #if defined(TEMPDIRNAMES) || defined(PROTO)
7221 static long	temp_count = 0;		/* Temp filename counter. */
7222 
7223 /*
7224  * Delete the temp directory and all files it contains.
7225  */
7226     void
7227 vim_deltempdir(void)
7228 {
7229     if (vim_tempdir != NULL)
7230     {
7231 	/* remove the trailing path separator */
7232 	gettail(vim_tempdir)[-1] = NUL;
7233 	delete_recursive(vim_tempdir);
7234 	VIM_CLEAR(vim_tempdir);
7235     }
7236 }
7237 
7238 /*
7239  * Directory "tempdir" was created.  Expand this name to a full path and put
7240  * it in "vim_tempdir".  This avoids that using ":cd" would confuse us.
7241  * "tempdir" must be no longer than MAXPATHL.
7242  */
7243     static void
7244 vim_settempdir(char_u *tempdir)
7245 {
7246     char_u	*buf;
7247 
7248     buf = alloc((unsigned)MAXPATHL + 2);
7249     if (buf != NULL)
7250     {
7251 	if (vim_FullName(tempdir, buf, MAXPATHL, FALSE) == FAIL)
7252 	    STRCPY(buf, tempdir);
7253 	add_pathsep(buf);
7254 	vim_tempdir = vim_strsave(buf);
7255 	vim_free(buf);
7256     }
7257 }
7258 #endif
7259 
7260 /*
7261  * vim_tempname(): Return a unique name that can be used for a temp file.
7262  *
7263  * The temp file is NOT guaranteed to be created.  If "keep" is FALSE it is
7264  * guaranteed to NOT be created.
7265  *
7266  * The returned pointer is to allocated memory.
7267  * The returned pointer is NULL if no valid name was found.
7268  */
7269     char_u  *
7270 vim_tempname(
7271     int	    extra_char UNUSED,  /* char to use in the name instead of '?' */
7272     int	    keep UNUSED)
7273 {
7274 #ifdef USE_TMPNAM
7275     char_u	itmp[L_tmpnam];	/* use tmpnam() */
7276 #elif defined(MSWIN)
7277     WCHAR	itmp[TEMPNAMELEN];
7278 #else
7279     char_u	itmp[TEMPNAMELEN];
7280 #endif
7281 
7282 #ifdef TEMPDIRNAMES
7283     static char	*(tempdirs[]) = {TEMPDIRNAMES};
7284     int		i;
7285 # ifndef EEXIST
7286     stat_T	st;
7287 # endif
7288 
7289     /*
7290      * This will create a directory for private use by this instance of Vim.
7291      * This is done once, and the same directory is used for all temp files.
7292      * This method avoids security problems because of symlink attacks et al.
7293      * It's also a bit faster, because we only need to check for an existing
7294      * file when creating the directory and not for each temp file.
7295      */
7296     if (vim_tempdir == NULL)
7297     {
7298 	/*
7299 	 * Try the entries in TEMPDIRNAMES to create the temp directory.
7300 	 */
7301 	for (i = 0; i < (int)(sizeof(tempdirs) / sizeof(char *)); ++i)
7302 	{
7303 # ifndef HAVE_MKDTEMP
7304 	    size_t	itmplen;
7305 	    long	nr;
7306 	    long	off;
7307 # endif
7308 
7309 	    /* Expand $TMP, leave room for "/v1100000/999999999".
7310 	     * Skip the directory check if the expansion fails. */
7311 	    expand_env((char_u *)tempdirs[i], itmp, TEMPNAMELEN - 20);
7312 	    if (itmp[0] != '$' && mch_isdir(itmp))
7313 	    {
7314 		/* directory exists */
7315 		add_pathsep(itmp);
7316 
7317 # ifdef HAVE_MKDTEMP
7318 		{
7319 #  if defined(UNIX) || defined(VMS)
7320 		    /* Make sure the umask doesn't remove the executable bit.
7321 		     * "repl" has been reported to use "177". */
7322 		    mode_t	umask_save = umask(077);
7323 #  endif
7324 		    /* Leave room for filename */
7325 		    STRCAT(itmp, "vXXXXXX");
7326 		    if (mkdtemp((char *)itmp) != NULL)
7327 			vim_settempdir(itmp);
7328 #  if defined(UNIX) || defined(VMS)
7329 		    (void)umask(umask_save);
7330 #  endif
7331 		}
7332 # else
7333 		/* Get an arbitrary number of up to 6 digits.  When it's
7334 		 * unlikely that it already exists it will be faster,
7335 		 * otherwise it doesn't matter.  The use of mkdir() avoids any
7336 		 * security problems because of the predictable number. */
7337 		nr = (mch_get_pid() + (long)time(NULL)) % 1000000L;
7338 		itmplen = STRLEN(itmp);
7339 
7340 		/* Try up to 10000 different values until we find a name that
7341 		 * doesn't exist. */
7342 		for (off = 0; off < 10000L; ++off)
7343 		{
7344 		    int		r;
7345 #  if defined(UNIX) || defined(VMS)
7346 		    mode_t	umask_save;
7347 #  endif
7348 
7349 		    sprintf((char *)itmp + itmplen, "v%ld", nr + off);
7350 #  ifndef EEXIST
7351 		    /* If mkdir() does not set errno to EEXIST, check for
7352 		     * existing file here.  There is a race condition then,
7353 		     * although it's fail-safe. */
7354 		    if (mch_stat((char *)itmp, &st) >= 0)
7355 			continue;
7356 #  endif
7357 #  if defined(UNIX) || defined(VMS)
7358 		    /* Make sure the umask doesn't remove the executable bit.
7359 		     * "repl" has been reported to use "177". */
7360 		    umask_save = umask(077);
7361 #  endif
7362 		    r = vim_mkdir(itmp, 0700);
7363 #  if defined(UNIX) || defined(VMS)
7364 		    (void)umask(umask_save);
7365 #  endif
7366 		    if (r == 0)
7367 		    {
7368 			vim_settempdir(itmp);
7369 			break;
7370 		    }
7371 #  ifdef EEXIST
7372 		    /* If the mkdir() didn't fail because the file/dir exists,
7373 		     * we probably can't create any dir here, try another
7374 		     * place. */
7375 		    if (errno != EEXIST)
7376 #  endif
7377 			break;
7378 		}
7379 # endif /* HAVE_MKDTEMP */
7380 		if (vim_tempdir != NULL)
7381 		    break;
7382 	    }
7383 	}
7384     }
7385 
7386     if (vim_tempdir != NULL)
7387     {
7388 	/* There is no need to check if the file exists, because we own the
7389 	 * directory and nobody else creates a file in it. */
7390 	sprintf((char *)itmp, "%s%ld", vim_tempdir, temp_count++);
7391 	return vim_strsave(itmp);
7392     }
7393 
7394     return NULL;
7395 
7396 #else /* TEMPDIRNAMES */
7397 
7398 # ifdef MSWIN
7399     WCHAR	wszTempFile[_MAX_PATH + 1];
7400     WCHAR	buf4[4];
7401     char_u	*retval;
7402     char_u	*p;
7403 
7404     wcscpy(itmp, L"");
7405     if (GetTempPathW(_MAX_PATH, wszTempFile) == 0)
7406     {
7407 	wszTempFile[0] = L'.';	// GetTempPathW() failed, use current dir
7408 	wszTempFile[1] = NUL;
7409     }
7410     wcscpy(buf4, L"VIM");
7411     buf4[2] = extra_char;   /* make it "VIa", "VIb", etc. */
7412     if (GetTempFileNameW(wszTempFile, buf4, 0, itmp) == 0)
7413 	return NULL;
7414     if (!keep)
7415 	// GetTempFileName() will create the file, we don't want that
7416 	(void)DeleteFileW(itmp);
7417 
7418     // Backslashes in a temp file name cause problems when filtering with
7419     // "sh".  NOTE: This also checks 'shellcmdflag' to help those people who
7420     // didn't set 'shellslash'.
7421     retval = utf16_to_enc(itmp, NULL);
7422     if (*p_shcf == '-' || p_ssl)
7423 	for (p = retval; *p; ++p)
7424 	    if (*p == '\\')
7425 		*p = '/';
7426     return retval;
7427 
7428 # else // MSWIN
7429 
7430 #  ifdef USE_TMPNAM
7431     char_u	*p;
7432 
7433     /* tmpnam() will make its own name */
7434     p = tmpnam((char *)itmp);
7435     if (p == NULL || *p == NUL)
7436 	return NULL;
7437 #  else
7438     char_u	*p;
7439 
7440 #   ifdef VMS_TEMPNAM
7441     /* mktemp() is not working on VMS.  It seems to be
7442      * a do-nothing function. Therefore we use tempnam().
7443      */
7444     sprintf((char *)itmp, "VIM%c", extra_char);
7445     p = (char_u *)tempnam("tmp:", (char *)itmp);
7446     if (p != NULL)
7447     {
7448 	/* VMS will use '.LIS' if we don't explicitly specify an extension,
7449 	 * and VIM will then be unable to find the file later */
7450 	STRCPY(itmp, p);
7451 	STRCAT(itmp, ".txt");
7452 	free(p);
7453     }
7454     else
7455 	return NULL;
7456 #   else
7457     STRCPY(itmp, TEMPNAME);
7458     if ((p = vim_strchr(itmp, '?')) != NULL)
7459 	*p = extra_char;
7460     if (mktemp((char *)itmp) == NULL)
7461 	return NULL;
7462 #   endif
7463 #  endif
7464 
7465     return vim_strsave(itmp);
7466 # endif // MSWIN
7467 #endif /* TEMPDIRNAMES */
7468 }
7469 
7470 #if defined(BACKSLASH_IN_FILENAME) || defined(PROTO)
7471 /*
7472  * Convert all backslashes in fname to forward slashes in-place, unless when
7473  * it looks like a URL.
7474  */
7475     void
7476 forward_slash(char_u *fname)
7477 {
7478     char_u	*p;
7479 
7480     if (path_with_url(fname))
7481 	return;
7482     for (p = fname; *p != NUL; ++p)
7483 	/* The Big5 encoding can have '\' in the trail byte. */
7484 	if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
7485 	    ++p;
7486 	else if (*p == '\\')
7487 	    *p = '/';
7488 }
7489 #endif
7490 
7491 /*
7492  * Try matching a filename with a "pattern" ("prog" is NULL), or use the
7493  * precompiled regprog "prog" ("pattern" is NULL).  That avoids calling
7494  * vim_regcomp() often.
7495  * Used for autocommands and 'wildignore'.
7496  * Returns TRUE if there is a match, FALSE otherwise.
7497  */
7498     int
7499 match_file_pat(
7500     char_u	*pattern,		/* pattern to match with */
7501     regprog_T	**prog,			/* pre-compiled regprog or NULL */
7502     char_u	*fname,			/* full path of file name */
7503     char_u	*sfname,		/* short file name or NULL */
7504     char_u	*tail,			/* tail of path */
7505     int		allow_dirs)		/* allow matching with dir */
7506 {
7507     regmatch_T	regmatch;
7508     int		result = FALSE;
7509 
7510     regmatch.rm_ic = p_fic; /* ignore case if 'fileignorecase' is set */
7511     if (prog != NULL)
7512 	regmatch.regprog = *prog;
7513     else
7514 	regmatch.regprog = vim_regcomp(pattern, RE_MAGIC);
7515 
7516     /*
7517      * Try for a match with the pattern with:
7518      * 1. the full file name, when the pattern has a '/'.
7519      * 2. the short file name, when the pattern has a '/'.
7520      * 3. the tail of the file name, when the pattern has no '/'.
7521      */
7522     if (regmatch.regprog != NULL
7523 	     && ((allow_dirs
7524 		     && (vim_regexec(&regmatch, fname, (colnr_T)0)
7525 			 || (sfname != NULL
7526 			     && vim_regexec(&regmatch, sfname, (colnr_T)0))))
7527 		 || (!allow_dirs && vim_regexec(&regmatch, tail, (colnr_T)0))))
7528 	result = TRUE;
7529 
7530     if (prog != NULL)
7531 	*prog = regmatch.regprog;
7532     else
7533 	vim_regfree(regmatch.regprog);
7534     return result;
7535 }
7536 
7537 #if defined(FEAT_WILDIGN) || defined(PROTO)
7538 /*
7539  * Return TRUE if a file matches with a pattern in "list".
7540  * "list" is a comma-separated list of patterns, like 'wildignore'.
7541  * "sfname" is the short file name or NULL, "ffname" the long file name.
7542  */
7543     int
7544 match_file_list(char_u *list, char_u *sfname, char_u *ffname)
7545 {
7546     char_u	buf[100];
7547     char_u	*tail;
7548     char_u	*regpat;
7549     char	allow_dirs;
7550     int		match;
7551     char_u	*p;
7552 
7553     tail = gettail(sfname);
7554 
7555     /* try all patterns in 'wildignore' */
7556     p = list;
7557     while (*p)
7558     {
7559 	copy_option_part(&p, buf, 100, ",");
7560 	regpat = file_pat_to_reg_pat(buf, NULL, &allow_dirs, FALSE);
7561 	if (regpat == NULL)
7562 	    break;
7563 	match = match_file_pat(regpat, NULL, ffname, sfname,
7564 						       tail, (int)allow_dirs);
7565 	vim_free(regpat);
7566 	if (match)
7567 	    return TRUE;
7568     }
7569     return FALSE;
7570 }
7571 #endif
7572 
7573 /*
7574  * Convert the given pattern "pat" which has shell style wildcards in it, into
7575  * a regular expression, and return the result in allocated memory.  If there
7576  * is a directory path separator to be matched, then TRUE is put in
7577  * allow_dirs, otherwise FALSE is put there -- webb.
7578  * Handle backslashes before special characters, like "\*" and "\ ".
7579  *
7580  * Returns NULL when out of memory.
7581  */
7582     char_u *
7583 file_pat_to_reg_pat(
7584     char_u	*pat,
7585     char_u	*pat_end,	/* first char after pattern or NULL */
7586     char	*allow_dirs,	/* Result passed back out in here */
7587     int		no_bslash UNUSED) /* Don't use a backward slash as pathsep */
7588 {
7589     int		size = 2; /* '^' at start, '$' at end */
7590     char_u	*endp;
7591     char_u	*reg_pat;
7592     char_u	*p;
7593     int		i;
7594     int		nested = 0;
7595     int		add_dollar = TRUE;
7596 
7597     if (allow_dirs != NULL)
7598 	*allow_dirs = FALSE;
7599     if (pat_end == NULL)
7600 	pat_end = pat + STRLEN(pat);
7601 
7602     for (p = pat; p < pat_end; p++)
7603     {
7604 	switch (*p)
7605 	{
7606 	    case '*':
7607 	    case '.':
7608 	    case ',':
7609 	    case '{':
7610 	    case '}':
7611 	    case '~':
7612 		size += 2;	/* extra backslash */
7613 		break;
7614 #ifdef BACKSLASH_IN_FILENAME
7615 	    case '\\':
7616 	    case '/':
7617 		size += 4;	/* could become "[\/]" */
7618 		break;
7619 #endif
7620 	    default:
7621 		size++;
7622 		if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
7623 		{
7624 		    ++p;
7625 		    ++size;
7626 		}
7627 		break;
7628 	}
7629     }
7630     reg_pat = alloc(size + 1);
7631     if (reg_pat == NULL)
7632 	return NULL;
7633 
7634     i = 0;
7635 
7636     if (pat[0] == '*')
7637 	while (pat[0] == '*' && pat < pat_end - 1)
7638 	    pat++;
7639     else
7640 	reg_pat[i++] = '^';
7641     endp = pat_end - 1;
7642     if (endp >= pat && *endp == '*')
7643     {
7644 	while (endp - pat > 0 && *endp == '*')
7645 	    endp--;
7646 	add_dollar = FALSE;
7647     }
7648     for (p = pat; *p && nested >= 0 && p <= endp; p++)
7649     {
7650 	switch (*p)
7651 	{
7652 	    case '*':
7653 		reg_pat[i++] = '.';
7654 		reg_pat[i++] = '*';
7655 		while (p[1] == '*')	/* "**" matches like "*" */
7656 		    ++p;
7657 		break;
7658 	    case '.':
7659 	    case '~':
7660 		reg_pat[i++] = '\\';
7661 		reg_pat[i++] = *p;
7662 		break;
7663 	    case '?':
7664 		reg_pat[i++] = '.';
7665 		break;
7666 	    case '\\':
7667 		if (p[1] == NUL)
7668 		    break;
7669 #ifdef BACKSLASH_IN_FILENAME
7670 		if (!no_bslash)
7671 		{
7672 		    /* translate:
7673 		     * "\x" to "\\x"  e.g., "dir\file"
7674 		     * "\*" to "\\.*" e.g., "dir\*.c"
7675 		     * "\?" to "\\."  e.g., "dir\??.c"
7676 		     * "\+" to "\+"   e.g., "fileX\+.c"
7677 		     */
7678 		    if ((vim_isfilec(p[1]) || p[1] == '*' || p[1] == '?')
7679 			    && p[1] != '+')
7680 		    {
7681 			reg_pat[i++] = '[';
7682 			reg_pat[i++] = '\\';
7683 			reg_pat[i++] = '/';
7684 			reg_pat[i++] = ']';
7685 			if (allow_dirs != NULL)
7686 			    *allow_dirs = TRUE;
7687 			break;
7688 		    }
7689 		}
7690 #endif
7691 		/* Undo escaping from ExpandEscape():
7692 		 * foo\?bar -> foo?bar
7693 		 * foo\%bar -> foo%bar
7694 		 * foo\,bar -> foo,bar
7695 		 * foo\ bar -> foo bar
7696 		 * Don't unescape \, * and others that are also special in a
7697 		 * regexp.
7698 		 * An escaped { must be unescaped since we use magic not
7699 		 * verymagic.  Use "\\\{n,m\}"" to get "\{n,m}".
7700 		 */
7701 		if (*++p == '?'
7702 #ifdef BACKSLASH_IN_FILENAME
7703 			&& no_bslash
7704 #endif
7705 			)
7706 		    reg_pat[i++] = '?';
7707 		else
7708 		    if (*p == ',' || *p == '%' || *p == '#'
7709 			       || vim_isspace(*p) || *p == '{' || *p == '}')
7710 			reg_pat[i++] = *p;
7711 		    else if (*p == '\\' && p[1] == '\\' && p[2] == '{')
7712 		    {
7713 			reg_pat[i++] = '\\';
7714 			reg_pat[i++] = '{';
7715 			p += 2;
7716 		    }
7717 		    else
7718 		    {
7719 			if (allow_dirs != NULL && vim_ispathsep(*p)
7720 #ifdef BACKSLASH_IN_FILENAME
7721 				&& (!no_bslash || *p != '\\')
7722 #endif
7723 				)
7724 			    *allow_dirs = TRUE;
7725 			reg_pat[i++] = '\\';
7726 			reg_pat[i++] = *p;
7727 		    }
7728 		break;
7729 #ifdef BACKSLASH_IN_FILENAME
7730 	    case '/':
7731 		reg_pat[i++] = '[';
7732 		reg_pat[i++] = '\\';
7733 		reg_pat[i++] = '/';
7734 		reg_pat[i++] = ']';
7735 		if (allow_dirs != NULL)
7736 		    *allow_dirs = TRUE;
7737 		break;
7738 #endif
7739 	    case '{':
7740 		reg_pat[i++] = '\\';
7741 		reg_pat[i++] = '(';
7742 		nested++;
7743 		break;
7744 	    case '}':
7745 		reg_pat[i++] = '\\';
7746 		reg_pat[i++] = ')';
7747 		--nested;
7748 		break;
7749 	    case ',':
7750 		if (nested)
7751 		{
7752 		    reg_pat[i++] = '\\';
7753 		    reg_pat[i++] = '|';
7754 		}
7755 		else
7756 		    reg_pat[i++] = ',';
7757 		break;
7758 	    default:
7759 		if (enc_dbcs != 0 && (*mb_ptr2len)(p) > 1)
7760 		    reg_pat[i++] = *p++;
7761 		else if (allow_dirs != NULL && vim_ispathsep(*p))
7762 		    *allow_dirs = TRUE;
7763 		reg_pat[i++] = *p;
7764 		break;
7765 	}
7766     }
7767     if (add_dollar)
7768 	reg_pat[i++] = '$';
7769     reg_pat[i] = NUL;
7770     if (nested != 0)
7771     {
7772 	if (nested < 0)
7773 	    emsg(_("E219: Missing {."));
7774 	else
7775 	    emsg(_("E220: Missing }."));
7776 	VIM_CLEAR(reg_pat);
7777     }
7778     return reg_pat;
7779 }
7780 
7781 #if defined(EINTR) || defined(PROTO)
7782 /*
7783  * Version of read() that retries when interrupted by EINTR (possibly
7784  * by a SIGWINCH).
7785  */
7786     long
7787 read_eintr(int fd, void *buf, size_t bufsize)
7788 {
7789     long ret;
7790 
7791     for (;;)
7792     {
7793 	ret = vim_read(fd, buf, bufsize);
7794 	if (ret >= 0 || errno != EINTR)
7795 	    break;
7796     }
7797     return ret;
7798 }
7799 
7800 /*
7801  * Version of write() that retries when interrupted by EINTR (possibly
7802  * by a SIGWINCH).
7803  */
7804     long
7805 write_eintr(int fd, void *buf, size_t bufsize)
7806 {
7807     long    ret = 0;
7808     long    wlen;
7809 
7810     /* Repeat the write() so long it didn't fail, other than being interrupted
7811      * by a signal. */
7812     while (ret < (long)bufsize)
7813     {
7814 	wlen = vim_write(fd, (char *)buf + ret, bufsize - ret);
7815 	if (wlen < 0)
7816 	{
7817 	    if (errno != EINTR)
7818 		break;
7819 	}
7820 	else
7821 	    ret += wlen;
7822     }
7823     return ret;
7824 }
7825 #endif
7826