xref: /vim-8.2.3635/src/mbyte.c (revision cb03397a)
1 /* vi:set ts=8 sts=4 sw=4:
2  *
3  * VIM - Vi IMproved	by Bram Moolenaar
4  * Multibyte extensions partly by Sung-Hoon Baek
5  *
6  * Do ":help uganda"  in Vim to read copying and usage conditions.
7  * Do ":help credits" in Vim to see a list of people who contributed.
8  * See README.txt for an overview of the Vim source code.
9  */
10 /*
11  * mbyte.c: Code specifically for handling multi-byte characters.
12  *
13  * The encoding used in the core is set with 'encoding'.  When 'encoding' is
14  * changed, the following four variables are set (for speed).
15  * Currently these types of character encodings are supported:
16  *
17  * "enc_dbcs"	    When non-zero it tells the type of double byte character
18  *		    encoding (Chinese, Korean, Japanese, etc.).
19  *		    The cell width on the display is equal to the number of
20  *		    bytes.  (exception: DBCS_JPNU with first byte 0x8e)
21  *		    Recognizing the first or second byte is difficult, it
22  *		    requires checking a byte sequence from the start.
23  * "enc_utf8"	    When TRUE use Unicode characters in UTF-8 encoding.
24  *		    The cell width on the display needs to be determined from
25  *		    the character value.
26  *		    Recognizing bytes is easy: 0xxx.xxxx is a single-byte
27  *		    char, 10xx.xxxx is a trailing byte, 11xx.xxxx is a leading
28  *		    byte of a multi-byte character.
29  *		    To make things complicated, up to six composing characters
30  *		    are allowed.  These are drawn on top of the first char.
31  *		    For most editing the sequence of bytes with composing
32  *		    characters included is considered to be one character.
33  * "enc_unicode"    When 2 use 16-bit Unicode characters (or UTF-16).
34  *		    When 4 use 32-but Unicode characters.
35  *		    Internally characters are stored in UTF-8 encoding to
36  *		    avoid NUL bytes.  Conversion happens when doing I/O.
37  *		    "enc_utf8" will also be TRUE.
38  *
39  * "has_mbyte" is set when "enc_dbcs" or "enc_utf8" is non-zero.
40  *
41  * If none of these is TRUE, 8-bit bytes are used for a character.  The
42  * encoding isn't currently specified (TODO).
43  *
44  * 'encoding' specifies the encoding used in the core.  This is in registers,
45  * text manipulation, buffers, etc.  Conversion has to be done when characters
46  * in another encoding are received or send:
47  *
48  *		       clipboard
49  *			   ^
50  *			   | (2)
51  *			   V
52  *		   +---------------+
53  *	      (1)  |		   | (3)
54  *  keyboard ----->|	 core	   |-----> display
55  *		   |		   |
56  *		   +---------------+
57  *			   ^
58  *			   | (4)
59  *			   V
60  *			 file
61  *
62  * (1) Typed characters arrive in the current locale.  Conversion is to be
63  *     done when 'encoding' is different from 'termencoding'.
64  * (2) Text will be made available with the encoding specified with
65  *     'encoding'.  If this is not sufficient, system-specific conversion
66  *     might be required.
67  * (3) For the GUI the correct font must be selected, no conversion done.
68  *     Otherwise, conversion is to be done when 'encoding' differs from
69  *     'termencoding'.  (Different in the GTK+ 2 port -- 'termencoding'
70  *     is always used for both input and output and must always be set to
71  *     "utf-8".  gui_mch_init() does this automatically.)
72  * (4) The encoding of the file is specified with 'fileencoding'.  Conversion
73  *     is to be done when it's different from 'encoding'.
74  *
75  * The viminfo file is a special case: Only text is converted, not file names.
76  * Vim scripts may contain an ":encoding" command.  This has an effect for
77  * some commands, like ":menutrans"
78  */
79 
80 #include "vim.h"
81 
82 #ifdef WIN32UNIX
83 # ifndef WIN32_LEAN_AND_MEAN
84 #  define WIN32_LEAN_AND_MEAN
85 # endif
86 # if defined(FEAT_GUI) || defined(FEAT_XCLIPBOARD)
87 #  include <X11/Xwindows.h>
88 #  define WINBYTE wBYTE
89 # else
90 #  include <windows.h>
91 #  define WINBYTE BYTE
92 # endif
93 # ifdef WIN32
94 #  undef WIN32	    /* Some windows.h define WIN32, we don't want that here. */
95 # endif
96 #else
97 # define WINBYTE BYTE
98 #endif
99 
100 #if (defined(WIN3264) || defined(WIN32UNIX)) && !defined(__MINGW32__)
101 # include <winnls.h>
102 #endif
103 
104 #ifdef FEAT_GUI_X11
105 # include <X11/Intrinsic.h>
106 #endif
107 #ifdef X_LOCALE
108 #include <X11/Xlocale.h>
109 #endif
110 
111 #if defined(FEAT_GUI_GTK) && defined(FEAT_XIM)
112 # if GTK_CHECK_VERSION(3,0,0)
113 #  include <gdk/gdkkeysyms-compat.h>
114 # else
115 #  include <gdk/gdkkeysyms.h>
116 # endif
117 # ifdef WIN3264
118 #  include <gdk/gdkwin32.h>
119 # else
120 #  include <gdk/gdkx.h>
121 # endif
122 #endif
123 
124 #ifdef HAVE_WCHAR_H
125 # include <wchar.h>
126 #endif
127 
128 #if 0
129 /* This has been disabled, because several people reported problems with the
130  * wcwidth() and iswprint() library functions, esp. for Hebrew. */
131 # ifdef __STDC_ISO_10646__
132 #  define USE_WCHAR_FUNCTIONS
133 # endif
134 #endif
135 
136 #if defined(FEAT_MBYTE) || defined(PROTO)
137 
138 static int enc_canon_search(char_u *name);
139 static int dbcs_char2len(int c);
140 static int dbcs_char2bytes(int c, char_u *buf);
141 static int dbcs_ptr2len(char_u *p);
142 static int dbcs_ptr2len_len(char_u *p, int size);
143 static int utf_ptr2cells_len(char_u *p, int size);
144 static int dbcs_char2cells(int c);
145 static int dbcs_ptr2cells_len(char_u *p, int size);
146 static int dbcs_ptr2char(char_u *p);
147 static int utf_safe_read_char_adv(char_u **s, size_t *n);
148 
149 /*
150  * Lookup table to quickly get the length in bytes of a UTF-8 character from
151  * the first byte of a UTF-8 string.
152  * Bytes which are illegal when used as the first byte have a 1.
153  * The NUL byte has length 1.
154  */
155 static char utf8len_tab[256] =
156 {
157     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
158     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
159     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
160     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
161     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
162     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
163     2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
164     3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1,
165 };
166 
167 /*
168  * Like utf8len_tab above, but using a zero for illegal lead bytes.
169  */
170 static char utf8len_tab_zero[256] =
171 {
172     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
173     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
174     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
175     1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
176     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
177     0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
178     2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
179     3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,0,0,
180 };
181 
182 /*
183  * XIM often causes trouble.  Define XIM_DEBUG to get a log of XIM callbacks
184  * in the "xim.log" file.
185  */
186 /* #define XIM_DEBUG */
187 #ifdef XIM_DEBUG
188     static void
189 xim_log(char *s, ...)
190 {
191     va_list arglist;
192     static FILE *fd = NULL;
193 
194     if (fd == (FILE *)-1)
195 	return;
196     if (fd == NULL)
197     {
198 	fd = mch_fopen("xim.log", "w");
199 	if (fd == NULL)
200 	{
201 	    EMSG("Cannot open xim.log");
202 	    fd = (FILE *)-1;
203 	    return;
204 	}
205     }
206 
207     va_start(arglist, s);
208     vfprintf(fd, s, arglist);
209     va_end(arglist);
210 }
211 #endif
212 
213 #endif
214 
215 #if defined(FEAT_MBYTE) || defined(FEAT_POSTSCRIPT) || defined(PROTO)
216 /*
217  * Canonical encoding names and their properties.
218  * "iso-8859-n" is handled by enc_canonize() directly.
219  */
220 static struct
221 {   char *name;		int prop;		int codepage;}
222 enc_canon_table[] =
223 {
224 #define IDX_LATIN_1	0
225     {"latin1",		ENC_8BIT + ENC_LATIN1,	1252},
226 #define IDX_ISO_2	1
227     {"iso-8859-2",	ENC_8BIT,		0},
228 #define IDX_ISO_3	2
229     {"iso-8859-3",	ENC_8BIT,		0},
230 #define IDX_ISO_4	3
231     {"iso-8859-4",	ENC_8BIT,		0},
232 #define IDX_ISO_5	4
233     {"iso-8859-5",	ENC_8BIT,		0},
234 #define IDX_ISO_6	5
235     {"iso-8859-6",	ENC_8BIT,		0},
236 #define IDX_ISO_7	6
237     {"iso-8859-7",	ENC_8BIT,		0},
238 #define IDX_ISO_8	7
239     {"iso-8859-8",	ENC_8BIT,		0},
240 #define IDX_ISO_9	8
241     {"iso-8859-9",	ENC_8BIT,		0},
242 #define IDX_ISO_10	9
243     {"iso-8859-10",	ENC_8BIT,		0},
244 #define IDX_ISO_11	10
245     {"iso-8859-11",	ENC_8BIT,		0},
246 #define IDX_ISO_13	11
247     {"iso-8859-13",	ENC_8BIT,		0},
248 #define IDX_ISO_14	12
249     {"iso-8859-14",	ENC_8BIT,		0},
250 #define IDX_ISO_15	13
251     {"iso-8859-15",	ENC_8BIT + ENC_LATIN9,	0},
252 #define IDX_KOI8_R	14
253     {"koi8-r",		ENC_8BIT,		0},
254 #define IDX_KOI8_U	15
255     {"koi8-u",		ENC_8BIT,		0},
256 #define IDX_UTF8	16
257     {"utf-8",		ENC_UNICODE,		0},
258 #define IDX_UCS2	17
259     {"ucs-2",		ENC_UNICODE + ENC_ENDIAN_B + ENC_2BYTE, 0},
260 #define IDX_UCS2LE	18
261     {"ucs-2le",		ENC_UNICODE + ENC_ENDIAN_L + ENC_2BYTE, 0},
262 #define IDX_UTF16	19
263     {"utf-16",		ENC_UNICODE + ENC_ENDIAN_B + ENC_2WORD, 0},
264 #define IDX_UTF16LE	20
265     {"utf-16le",	ENC_UNICODE + ENC_ENDIAN_L + ENC_2WORD, 0},
266 #define IDX_UCS4	21
267     {"ucs-4",		ENC_UNICODE + ENC_ENDIAN_B + ENC_4BYTE, 0},
268 #define IDX_UCS4LE	22
269     {"ucs-4le",		ENC_UNICODE + ENC_ENDIAN_L + ENC_4BYTE, 0},
270 
271     /* For debugging DBCS encoding on Unix. */
272 #define IDX_DEBUG	23
273     {"debug",		ENC_DBCS,		DBCS_DEBUG},
274 #define IDX_EUC_JP	24
275     {"euc-jp",		ENC_DBCS,		DBCS_JPNU},
276 #define IDX_SJIS	25
277     {"sjis",		ENC_DBCS,		DBCS_JPN},
278 #define IDX_EUC_KR	26
279     {"euc-kr",		ENC_DBCS,		DBCS_KORU},
280 #define IDX_EUC_CN	27
281     {"euc-cn",		ENC_DBCS,		DBCS_CHSU},
282 #define IDX_EUC_TW	28
283     {"euc-tw",		ENC_DBCS,		DBCS_CHTU},
284 #define IDX_BIG5	29
285     {"big5",		ENC_DBCS,		DBCS_CHT},
286 
287     /* MS-DOS and MS-Windows codepages are included here, so that they can be
288      * used on Unix too.  Most of them are similar to ISO-8859 encodings, but
289      * not exactly the same. */
290 #define IDX_CP437	30
291     {"cp437",		ENC_8BIT,		437}, /* like iso-8859-1 */
292 #define IDX_CP737	31
293     {"cp737",		ENC_8BIT,		737}, /* like iso-8859-7 */
294 #define IDX_CP775	32
295     {"cp775",		ENC_8BIT,		775}, /* Baltic */
296 #define IDX_CP850	33
297     {"cp850",		ENC_8BIT,		850}, /* like iso-8859-4 */
298 #define IDX_CP852	34
299     {"cp852",		ENC_8BIT,		852}, /* like iso-8859-1 */
300 #define IDX_CP855	35
301     {"cp855",		ENC_8BIT,		855}, /* like iso-8859-2 */
302 #define IDX_CP857	36
303     {"cp857",		ENC_8BIT,		857}, /* like iso-8859-5 */
304 #define IDX_CP860	37
305     {"cp860",		ENC_8BIT,		860}, /* like iso-8859-9 */
306 #define IDX_CP861	38
307     {"cp861",		ENC_8BIT,		861}, /* like iso-8859-1 */
308 #define IDX_CP862	39
309     {"cp862",		ENC_8BIT,		862}, /* like iso-8859-1 */
310 #define IDX_CP863	40
311     {"cp863",		ENC_8BIT,		863}, /* like iso-8859-8 */
312 #define IDX_CP865	41
313     {"cp865",		ENC_8BIT,		865}, /* like iso-8859-1 */
314 #define IDX_CP866	42
315     {"cp866",		ENC_8BIT,		866}, /* like iso-8859-5 */
316 #define IDX_CP869	43
317     {"cp869",		ENC_8BIT,		869}, /* like iso-8859-7 */
318 #define IDX_CP874	44
319     {"cp874",		ENC_8BIT,		874}, /* Thai */
320 #define IDX_CP932	45
321     {"cp932",		ENC_DBCS,		DBCS_JPN},
322 #define IDX_CP936	46
323     {"cp936",		ENC_DBCS,		DBCS_CHS},
324 #define IDX_CP949	47
325     {"cp949",		ENC_DBCS,		DBCS_KOR},
326 #define IDX_CP950	48
327     {"cp950",		ENC_DBCS,		DBCS_CHT},
328 #define IDX_CP1250	49
329     {"cp1250",		ENC_8BIT,		1250}, /* Czech, Polish, etc. */
330 #define IDX_CP1251	50
331     {"cp1251",		ENC_8BIT,		1251}, /* Cyrillic */
332     /* cp1252 is considered to be equal to latin1 */
333 #define IDX_CP1253	51
334     {"cp1253",		ENC_8BIT,		1253}, /* Greek */
335 #define IDX_CP1254	52
336     {"cp1254",		ENC_8BIT,		1254}, /* Turkish */
337 #define IDX_CP1255	53
338     {"cp1255",		ENC_8BIT,		1255}, /* Hebrew */
339 #define IDX_CP1256	54
340     {"cp1256",		ENC_8BIT,		1256}, /* Arabic */
341 #define IDX_CP1257	55
342     {"cp1257",		ENC_8BIT,		1257}, /* Baltic */
343 #define IDX_CP1258	56
344     {"cp1258",		ENC_8BIT,		1258}, /* Vietnamese */
345 
346 #define IDX_MACROMAN	57
347     {"macroman",	ENC_8BIT + ENC_MACROMAN, 0},	/* Mac OS */
348 #define IDX_DECMCS	58
349     {"dec-mcs",		ENC_8BIT,		0},	/* DEC MCS */
350 #define IDX_HPROMAN8	59
351     {"hp-roman8",	ENC_8BIT,		0},	/* HP Roman8 */
352 #define IDX_COUNT	60
353 };
354 
355 /*
356  * Aliases for encoding names.
357  */
358 static struct
359 {   char *name;		int canon;}
360 enc_alias_table[] =
361 {
362     {"ansi",		IDX_LATIN_1},
363     {"iso-8859-1",	IDX_LATIN_1},
364     {"latin2",		IDX_ISO_2},
365     {"latin3",		IDX_ISO_3},
366     {"latin4",		IDX_ISO_4},
367     {"cyrillic",	IDX_ISO_5},
368     {"arabic",		IDX_ISO_6},
369     {"greek",		IDX_ISO_7},
370 #ifdef WIN3264
371     {"hebrew",		IDX_CP1255},
372 #else
373     {"hebrew",		IDX_ISO_8},
374 #endif
375     {"latin5",		IDX_ISO_9},
376     {"turkish",		IDX_ISO_9}, /* ? */
377     {"latin6",		IDX_ISO_10},
378     {"nordic",		IDX_ISO_10}, /* ? */
379     {"thai",		IDX_ISO_11}, /* ? */
380     {"latin7",		IDX_ISO_13},
381     {"latin8",		IDX_ISO_14},
382     {"latin9",		IDX_ISO_15},
383     {"utf8",		IDX_UTF8},
384     {"unicode",		IDX_UCS2},
385     {"ucs2",		IDX_UCS2},
386     {"ucs2be",		IDX_UCS2},
387     {"ucs-2be",		IDX_UCS2},
388     {"ucs2le",		IDX_UCS2LE},
389     {"utf16",		IDX_UTF16},
390     {"utf16be",		IDX_UTF16},
391     {"utf-16be",	IDX_UTF16},
392     {"utf16le",		IDX_UTF16LE},
393     {"ucs4",		IDX_UCS4},
394     {"ucs4be",		IDX_UCS4},
395     {"ucs-4be",		IDX_UCS4},
396     {"ucs4le",		IDX_UCS4LE},
397     {"utf32",		IDX_UCS4},
398     {"utf-32",		IDX_UCS4},
399     {"utf32be",		IDX_UCS4},
400     {"utf-32be",	IDX_UCS4},
401     {"utf32le",		IDX_UCS4LE},
402     {"utf-32le",	IDX_UCS4LE},
403     {"932",		IDX_CP932},
404     {"949",		IDX_CP949},
405     {"936",		IDX_CP936},
406     {"gbk",		IDX_CP936},
407     {"950",		IDX_CP950},
408     {"eucjp",		IDX_EUC_JP},
409     {"unix-jis",	IDX_EUC_JP},
410     {"ujis",		IDX_EUC_JP},
411     {"shift-jis",	IDX_SJIS},
412     {"pck",		IDX_SJIS},	/* Sun: PCK */
413     {"euckr",		IDX_EUC_KR},
414     {"5601",		IDX_EUC_KR},	/* Sun: KS C 5601 */
415     {"euccn",		IDX_EUC_CN},
416     {"gb2312",		IDX_EUC_CN},
417     {"euctw",		IDX_EUC_TW},
418 #if defined(WIN3264) || defined(WIN32UNIX) || defined(MACOS)
419     {"japan",		IDX_CP932},
420     {"korea",		IDX_CP949},
421     {"prc",		IDX_CP936},
422     {"chinese",		IDX_CP936},
423     {"taiwan",		IDX_CP950},
424     {"big5",		IDX_CP950},
425 #else
426     {"japan",		IDX_EUC_JP},
427     {"korea",		IDX_EUC_KR},
428     {"prc",		IDX_EUC_CN},
429     {"chinese",		IDX_EUC_CN},
430     {"taiwan",		IDX_EUC_TW},
431     {"cp950",		IDX_BIG5},
432     {"950",		IDX_BIG5},
433 #endif
434     {"mac",		IDX_MACROMAN},
435     {"mac-roman",	IDX_MACROMAN},
436     {NULL,		0}
437 };
438 
439 #ifndef CP_UTF8
440 # define CP_UTF8 65001	/* magic number from winnls.h */
441 #endif
442 
443 /*
444  * Find encoding "name" in the list of canonical encoding names.
445  * Returns -1 if not found.
446  */
447     static int
448 enc_canon_search(char_u *name)
449 {
450     int		i;
451 
452     for (i = 0; i < IDX_COUNT; ++i)
453 	if (STRCMP(name, enc_canon_table[i].name) == 0)
454 	    return i;
455     return -1;
456 }
457 
458 #endif
459 
460 #if defined(FEAT_MBYTE) || defined(PROTO)
461 
462 /*
463  * Find canonical encoding "name" in the list and return its properties.
464  * Returns 0 if not found.
465  */
466     int
467 enc_canon_props(char_u *name)
468 {
469     int		i;
470 
471     i = enc_canon_search(name);
472     if (i >= 0)
473 	return enc_canon_table[i].prop;
474 #ifdef WIN3264
475     if (name[0] == 'c' && name[1] == 'p' && VIM_ISDIGIT(name[2]))
476     {
477 	CPINFO	cpinfo;
478 
479 	/* Get info on this codepage to find out what it is. */
480 	if (GetCPInfo(atoi((char *)name + 2), &cpinfo) != 0)
481 	{
482 	    if (cpinfo.MaxCharSize == 1) /* some single-byte encoding */
483 		return ENC_8BIT;
484 	    if (cpinfo.MaxCharSize == 2
485 		    && (cpinfo.LeadByte[0] != 0 || cpinfo.LeadByte[1] != 0))
486 		/* must be a DBCS encoding */
487 		return ENC_DBCS;
488 	}
489 	return 0;
490     }
491 #endif
492     if (STRNCMP(name, "2byte-", 6) == 0)
493 	return ENC_DBCS;
494     if (STRNCMP(name, "8bit-", 5) == 0 || STRNCMP(name, "iso-8859-", 9) == 0)
495 	return ENC_8BIT;
496     return 0;
497 }
498 
499 /*
500  * Set up for using multi-byte characters.
501  * Called in three cases:
502  * - by main() to initialize (p_enc == NULL)
503  * - by set_init_1() after 'encoding' was set to its default.
504  * - by do_set() when 'encoding' has been set.
505  * p_enc must have been passed through enc_canonize() already.
506  * Sets the "enc_unicode", "enc_utf8", "enc_dbcs" and "has_mbyte" flags.
507  * Fills mb_bytelen_tab[] and returns NULL when there are no problems.
508  * When there is something wrong: Returns an error message and doesn't change
509  * anything.
510  */
511     char_u *
512 mb_init(void)
513 {
514     int		i;
515     int		idx;
516     int		n;
517     int		enc_dbcs_new = 0;
518 #if defined(USE_ICONV) && !defined(WIN3264) && !defined(WIN32UNIX) \
519 	&& !defined(MACOS)
520 # define LEN_FROM_CONV
521     vimconv_T	vimconv;
522     char_u	*p;
523 #endif
524 
525     if (p_enc == NULL)
526     {
527 	/* Just starting up: set the whole table to one's. */
528 	for (i = 0; i < 256; ++i)
529 	    mb_bytelen_tab[i] = 1;
530 	input_conv.vc_type = CONV_NONE;
531 	input_conv.vc_factor = 1;
532 	output_conv.vc_type = CONV_NONE;
533 	return NULL;
534     }
535 
536 #ifdef WIN3264
537     if (p_enc[0] == 'c' && p_enc[1] == 'p' && VIM_ISDIGIT(p_enc[2]))
538     {
539 	CPINFO	cpinfo;
540 
541 	/* Get info on this codepage to find out what it is. */
542 	if (GetCPInfo(atoi((char *)p_enc + 2), &cpinfo) != 0)
543 	{
544 	    if (cpinfo.MaxCharSize == 1)
545 	    {
546 		/* some single-byte encoding */
547 		enc_unicode = 0;
548 		enc_utf8 = FALSE;
549 	    }
550 	    else if (cpinfo.MaxCharSize == 2
551 		    && (cpinfo.LeadByte[0] != 0 || cpinfo.LeadByte[1] != 0))
552 	    {
553 		/* must be a DBCS encoding, check below */
554 		enc_dbcs_new = atoi((char *)p_enc + 2);
555 	    }
556 	    else
557 		goto codepage_invalid;
558 	}
559 	else if (GetLastError() == ERROR_INVALID_PARAMETER)
560 	{
561 codepage_invalid:
562 	    return (char_u *)N_("E543: Not a valid codepage");
563 	}
564     }
565 #endif
566     else if (STRNCMP(p_enc, "8bit-", 5) == 0
567 	    || STRNCMP(p_enc, "iso-8859-", 9) == 0)
568     {
569 	/* Accept any "8bit-" or "iso-8859-" name. */
570 	enc_unicode = 0;
571 	enc_utf8 = FALSE;
572     }
573     else if (STRNCMP(p_enc, "2byte-", 6) == 0)
574     {
575 #ifdef WIN3264
576 	/* Windows: accept only valid codepage numbers, check below. */
577 	if (p_enc[6] != 'c' || p_enc[7] != 'p'
578 			      || (enc_dbcs_new = atoi((char *)p_enc + 8)) == 0)
579 	    return e_invarg;
580 #else
581 	/* Unix: accept any "2byte-" name, assume current locale. */
582 	enc_dbcs_new = DBCS_2BYTE;
583 #endif
584     }
585     else if ((idx = enc_canon_search(p_enc)) >= 0)
586     {
587 	i = enc_canon_table[idx].prop;
588 	if (i & ENC_UNICODE)
589 	{
590 	    /* Unicode */
591 	    enc_utf8 = TRUE;
592 	    if (i & (ENC_2BYTE | ENC_2WORD))
593 		enc_unicode = 2;
594 	    else if (i & ENC_4BYTE)
595 		enc_unicode = 4;
596 	    else
597 		enc_unicode = 0;
598 	}
599 	else if (i & ENC_DBCS)
600 	{
601 	    /* 2byte, handle below */
602 	    enc_dbcs_new = enc_canon_table[idx].codepage;
603 	}
604 	else
605 	{
606 	    /* Must be 8-bit. */
607 	    enc_unicode = 0;
608 	    enc_utf8 = FALSE;
609 	}
610     }
611     else    /* Don't know what encoding this is, reject it. */
612 	return e_invarg;
613 
614     if (enc_dbcs_new != 0)
615     {
616 #ifdef WIN3264
617 	/* Check if the DBCS code page is OK. */
618 	if (!IsValidCodePage(enc_dbcs_new))
619 	    goto codepage_invalid;
620 #endif
621 	enc_unicode = 0;
622 	enc_utf8 = FALSE;
623     }
624     enc_dbcs = enc_dbcs_new;
625     has_mbyte = (enc_dbcs != 0 || enc_utf8);
626 
627 #if defined(WIN3264) || defined(FEAT_CYGWIN_WIN32_CLIPBOARD)
628     enc_codepage = encname2codepage(p_enc);
629     enc_latin9 = (STRCMP(p_enc, "iso-8859-15") == 0);
630 #endif
631 
632     /* Detect an encoding that uses latin1 characters. */
633     enc_latin1like = (enc_utf8 || STRCMP(p_enc, "latin1") == 0
634 					|| STRCMP(p_enc, "iso-8859-15") == 0);
635 
636     /*
637      * Set the function pointers.
638      */
639     if (enc_utf8)
640     {
641 	mb_ptr2len = utfc_ptr2len;
642 	mb_ptr2len_len = utfc_ptr2len_len;
643 	mb_char2len = utf_char2len;
644 	mb_char2bytes = utf_char2bytes;
645 	mb_ptr2cells = utf_ptr2cells;
646 	mb_ptr2cells_len = utf_ptr2cells_len;
647 	mb_char2cells = utf_char2cells;
648 	mb_off2cells = utf_off2cells;
649 	mb_ptr2char = utf_ptr2char;
650 	mb_head_off = utf_head_off;
651     }
652     else if (enc_dbcs != 0)
653     {
654 	mb_ptr2len = dbcs_ptr2len;
655 	mb_ptr2len_len = dbcs_ptr2len_len;
656 	mb_char2len = dbcs_char2len;
657 	mb_char2bytes = dbcs_char2bytes;
658 	mb_ptr2cells = dbcs_ptr2cells;
659 	mb_ptr2cells_len = dbcs_ptr2cells_len;
660 	mb_char2cells = dbcs_char2cells;
661 	mb_off2cells = dbcs_off2cells;
662 	mb_ptr2char = dbcs_ptr2char;
663 	mb_head_off = dbcs_head_off;
664     }
665     else
666     {
667 	mb_ptr2len = latin_ptr2len;
668 	mb_ptr2len_len = latin_ptr2len_len;
669 	mb_char2len = latin_char2len;
670 	mb_char2bytes = latin_char2bytes;
671 	mb_ptr2cells = latin_ptr2cells;
672 	mb_ptr2cells_len = latin_ptr2cells_len;
673 	mb_char2cells = latin_char2cells;
674 	mb_off2cells = latin_off2cells;
675 	mb_ptr2char = latin_ptr2char;
676 	mb_head_off = latin_head_off;
677     }
678 
679     /*
680      * Fill the mb_bytelen_tab[] for MB_BYTE2LEN().
681      */
682 #ifdef LEN_FROM_CONV
683     /* When 'encoding' is different from the current locale mblen() won't
684      * work.  Use conversion to "utf-8" instead. */
685     vimconv.vc_type = CONV_NONE;
686     if (enc_dbcs)
687     {
688 	p = enc_locale();
689 	if (p == NULL || STRCMP(p, p_enc) != 0)
690 	{
691 	    convert_setup(&vimconv, p_enc, (char_u *)"utf-8");
692 	    vimconv.vc_fail = TRUE;
693 	}
694 	vim_free(p);
695     }
696 #endif
697 
698     for (i = 0; i < 256; ++i)
699     {
700 	/* Our own function to reliably check the length of UTF-8 characters,
701 	 * independent of mblen(). */
702 	if (enc_utf8)
703 	    n = utf8len_tab[i];
704 	else if (enc_dbcs == 0)
705 	    n = 1;
706 	else
707 	{
708 #if defined(WIN3264) || defined(WIN32UNIX)
709 	    /* enc_dbcs is set by setting 'fileencoding'.  It becomes a Windows
710 	     * CodePage identifier, which we can pass directly in to Windows
711 	     * API */
712 	    n = IsDBCSLeadByteEx(enc_dbcs, (WINBYTE)i) ? 2 : 1;
713 #else
714 # if defined(MACOS) || defined(__amigaos4__) || defined(__ANDROID__)
715 	    /*
716 	     * if mblen() is not available, character which MSB is turned on
717 	     * are treated as leading byte character. (note : This assumption
718 	     * is not always true.)
719 	     */
720 	    n = (i & 0x80) ? 2 : 1;
721 # else
722 	    char buf[MB_MAXBYTES + 1];
723 # ifdef X_LOCALE
724 #  ifndef mblen
725 #   define mblen _Xmblen
726 #  endif
727 # endif
728 	    if (i == NUL)	/* just in case mblen() can't handle "" */
729 		n = 1;
730 	    else
731 	    {
732 		buf[0] = i;
733 		buf[1] = 0;
734 #ifdef LEN_FROM_CONV
735 		if (vimconv.vc_type != CONV_NONE)
736 		{
737 		    /*
738 		     * string_convert() should fail when converting the first
739 		     * byte of a double-byte character.
740 		     */
741 		    p = string_convert(&vimconv, (char_u *)buf, NULL);
742 		    if (p != NULL)
743 		    {
744 			vim_free(p);
745 			n = 1;
746 		    }
747 		    else
748 			n = 2;
749 		}
750 		else
751 #endif
752 		{
753 		    /*
754 		     * mblen() should return -1 for invalid (means the leading
755 		     * multibyte) character.  However there are some platforms
756 		     * where mblen() returns 0 for invalid character.
757 		     * Therefore, following condition includes 0.
758 		     */
759 		    ignored = mblen(NULL, 0);	/* First reset the state. */
760 		    if (mblen(buf, (size_t)1) <= 0)
761 			n = 2;
762 		    else
763 			n = 1;
764 		}
765 	    }
766 # endif
767 #endif
768 	}
769 
770 	mb_bytelen_tab[i] = n;
771     }
772 
773 #ifdef LEN_FROM_CONV
774     convert_setup(&vimconv, NULL, NULL);
775 #endif
776 
777     /* The cell width depends on the type of multi-byte characters. */
778     (void)init_chartab();
779 
780     /* When enc_utf8 is set or reset, (de)allocate ScreenLinesUC[] */
781     screenalloc(FALSE);
782 
783     /* When using Unicode, set default for 'fileencodings'. */
784     if (enc_utf8 && !option_was_set((char_u *)"fencs"))
785 	set_string_option_direct((char_u *)"fencs", -1,
786 		       (char_u *)"ucs-bom,utf-8,default,latin1", OPT_FREE, 0);
787 
788 #if defined(HAVE_BIND_TEXTDOMAIN_CODESET) && defined(FEAT_GETTEXT)
789     /* GNU gettext 0.10.37 supports this feature: set the codeset used for
790      * translated messages independently from the current locale. */
791     (void)bind_textdomain_codeset(VIMPACKAGE,
792 					  enc_utf8 ? "utf-8" : (char *)p_enc);
793 #endif
794 
795 #ifdef WIN32
796     /* When changing 'encoding' while starting up, then convert the command
797      * line arguments from the active codepage to 'encoding'. */
798     if (starting != 0)
799 	fix_arg_enc();
800 #endif
801 
802 #ifdef FEAT_AUTOCMD
803     /* Fire an autocommand to let people do custom font setup. This must be
804      * after Vim has been setup for the new encoding. */
805     apply_autocmds(EVENT_ENCODINGCHANGED, NULL, (char_u *)"", FALSE, curbuf);
806 #endif
807 
808 #ifdef FEAT_SPELL
809     /* Need to reload spell dictionaries */
810     spell_reload();
811 #endif
812 
813     return NULL;
814 }
815 
816 /*
817  * Return the size of the BOM for the current buffer:
818  * 0 - no BOM
819  * 2 - UCS-2 or UTF-16 BOM
820  * 4 - UCS-4 BOM
821  * 3 - UTF-8 BOM
822  */
823     int
824 bomb_size(void)
825 {
826     int n = 0;
827 
828     if (curbuf->b_p_bomb && !curbuf->b_p_bin)
829     {
830 	if (*curbuf->b_p_fenc == NUL)
831 	{
832 	    if (enc_utf8)
833 	    {
834 		if (enc_unicode != 0)
835 		    n = enc_unicode;
836 		else
837 		    n = 3;
838 	    }
839 	}
840 	else if (STRCMP(curbuf->b_p_fenc, "utf-8") == 0)
841 	    n = 3;
842 	else if (STRNCMP(curbuf->b_p_fenc, "ucs-2", 5) == 0
843 		|| STRNCMP(curbuf->b_p_fenc, "utf-16", 6) == 0)
844 	    n = 2;
845 	else if (STRNCMP(curbuf->b_p_fenc, "ucs-4", 5) == 0)
846 	    n = 4;
847     }
848     return n;
849 }
850 
851 /*
852  * Remove all BOM from "s" by moving remaining text.
853  */
854     void
855 remove_bom(char_u *s)
856 {
857     if (enc_utf8)
858     {
859 	char_u *p = s;
860 
861 	while ((p = vim_strbyte(p, 0xef)) != NULL)
862 	{
863 	    if (p[1] == 0xbb && p[2] == 0xbf)
864 		STRMOVE(p, p + 3);
865 	    else
866 		++p;
867 	}
868     }
869 }
870 
871 /*
872  * Get class of pointer:
873  * 0 for blank or NUL
874  * 1 for punctuation
875  * 2 for an (ASCII) word character
876  * >2 for other word characters
877  */
878     int
879 mb_get_class(char_u *p)
880 {
881     return mb_get_class_buf(p, curbuf);
882 }
883 
884     int
885 mb_get_class_buf(char_u *p, buf_T *buf)
886 {
887     if (MB_BYTE2LEN(p[0]) == 1)
888     {
889 	if (p[0] == NUL || vim_iswhite(p[0]))
890 	    return 0;
891 	if (vim_iswordc_buf(p[0], buf))
892 	    return 2;
893 	return 1;
894     }
895     if (enc_dbcs != 0 && p[0] != NUL && p[1] != NUL)
896 	return dbcs_class(p[0], p[1]);
897     if (enc_utf8)
898 	return utf_class(utf_ptr2char(p));
899     return 0;
900 }
901 
902 /*
903  * Get class of a double-byte character.  This always returns 3 or bigger.
904  * TODO: Should return 1 for punctuation.
905  */
906     int
907 dbcs_class(unsigned lead, unsigned trail)
908 {
909     switch (enc_dbcs)
910     {
911 	/* please add classify routine for your language in here */
912 
913 	case DBCS_JPNU:	/* ? */
914 	case DBCS_JPN:
915 	    {
916 		/* JIS code classification */
917 		unsigned char lb = lead;
918 		unsigned char tb = trail;
919 
920 		/* convert process code to JIS */
921 # if defined(WIN3264) || defined(WIN32UNIX) || defined(MACOS)
922 		/* process code is SJIS */
923 		if (lb <= 0x9f)
924 		    lb = (lb - 0x81) * 2 + 0x21;
925 		else
926 		    lb = (lb - 0xc1) * 2 + 0x21;
927 		if (tb <= 0x7e)
928 		    tb -= 0x1f;
929 		else if (tb <= 0x9e)
930 		    tb -= 0x20;
931 		else
932 		{
933 		    tb -= 0x7e;
934 		    lb += 1;
935 		}
936 # else
937 		/*
938 		 * XXX: Code page identification can not use with all
939 		 *	    system! So, some other encoding information
940 		 *	    will be needed.
941 		 *	    In japanese: SJIS,EUC,UNICODE,(JIS)
942 		 *	    Note that JIS-code system don't use as
943 		 *	    process code in most system because it uses
944 		 *	    escape sequences(JIS is context depend encoding).
945 		 */
946 		/* assume process code is JAPANESE-EUC */
947 		lb &= 0x7f;
948 		tb &= 0x7f;
949 # endif
950 		/* exceptions */
951 		switch (lb << 8 | tb)
952 		{
953 		    case 0x2121: /* ZENKAKU space */
954 			return 0;
955 		    case 0x2122: /* TOU-TEN (Japanese comma) */
956 		    case 0x2123: /* KU-TEN (Japanese period) */
957 		    case 0x2124: /* ZENKAKU comma */
958 		    case 0x2125: /* ZENKAKU period */
959 			return 1;
960 		    case 0x213c: /* prolongedsound handled as KATAKANA */
961 			return 13;
962 		}
963 		/* sieved by KU code */
964 		switch (lb)
965 		{
966 		    case 0x21:
967 		    case 0x22:
968 			/* special symbols */
969 			return 10;
970 		    case 0x23:
971 			/* alpha-numeric */
972 			return 11;
973 		    case 0x24:
974 			/* hiragana */
975 			return 12;
976 		    case 0x25:
977 			/* katakana */
978 			return 13;
979 		    case 0x26:
980 			/* greek */
981 			return 14;
982 		    case 0x27:
983 			/* russian */
984 			return 15;
985 		    case 0x28:
986 			/* lines */
987 			return 16;
988 		    default:
989 			/* kanji */
990 			return 17;
991 		}
992 	    }
993 
994 	case DBCS_KORU:	/* ? */
995 	case DBCS_KOR:
996 	    {
997 		/* KS code classification */
998 		unsigned char c1 = lead;
999 		unsigned char c2 = trail;
1000 
1001 		/*
1002 		 * 20 : Hangul
1003 		 * 21 : Hanja
1004 		 * 22 : Symbols
1005 		 * 23 : Alpha-numeric/Roman Letter (Full width)
1006 		 * 24 : Hangul Letter(Alphabet)
1007 		 * 25 : Roman Numeral/Greek Letter
1008 		 * 26 : Box Drawings
1009 		 * 27 : Unit Symbols
1010 		 * 28 : Circled/Parenthesized Letter
1011 		 * 29 : Hiragana/Katakana
1012 		 * 30 : Cyrillic Letter
1013 		 */
1014 
1015 		if (c1 >= 0xB0 && c1 <= 0xC8)
1016 		    /* Hangul */
1017 		    return 20;
1018 #if defined(WIN3264) || defined(WIN32UNIX)
1019 		else if (c1 <= 0xA0 || c2 <= 0xA0)
1020 		    /* Extended Hangul Region : MS UHC(Unified Hangul Code) */
1021 		    /* c1: 0x81-0xA0 with c2: 0x41-0x5A, 0x61-0x7A, 0x81-0xFE
1022 		     * c1: 0xA1-0xC6 with c2: 0x41-0x5A, 0x61-0x7A, 0x81-0xA0
1023 		     */
1024 		    return 20;
1025 #endif
1026 
1027 		else if (c1 >= 0xCA && c1 <= 0xFD)
1028 		    /* Hanja */
1029 		    return 21;
1030 		else switch (c1)
1031 		{
1032 		    case 0xA1:
1033 		    case 0xA2:
1034 			/* Symbols */
1035 			return 22;
1036 		    case 0xA3:
1037 			/* Alpha-numeric */
1038 			return 23;
1039 		    case 0xA4:
1040 			/* Hangul Letter(Alphabet) */
1041 			return 24;
1042 		    case 0xA5:
1043 			/* Roman Numeral/Greek Letter */
1044 			return 25;
1045 		    case 0xA6:
1046 			/* Box Drawings */
1047 			return 26;
1048 		    case 0xA7:
1049 			/* Unit Symbols */
1050 			return 27;
1051 		    case 0xA8:
1052 		    case 0xA9:
1053 			if (c2 <= 0xAF)
1054 			    return 25;  /* Roman Letter */
1055 			else if (c2 >= 0xF6)
1056 			    return 22;  /* Symbols */
1057 			else
1058 			    /* Circled/Parenthesized Letter */
1059 			    return 28;
1060 		    case 0xAA:
1061 		    case 0xAB:
1062 			/* Hiragana/Katakana */
1063 			return 29;
1064 		    case 0xAC:
1065 			/* Cyrillic Letter */
1066 			return 30;
1067 		}
1068 	    }
1069 	default:
1070 	    break;
1071     }
1072     return 3;
1073 }
1074 
1075 /*
1076  * mb_char2len() function pointer.
1077  * Return length in bytes of character "c".
1078  * Returns 1 for a single-byte character.
1079  */
1080     int
1081 latin_char2len(int c UNUSED)
1082 {
1083     return 1;
1084 }
1085 
1086     static int
1087 dbcs_char2len(
1088     int		c)
1089 {
1090     if (c >= 0x100)
1091 	return 2;
1092     return 1;
1093 }
1094 
1095 /*
1096  * mb_char2bytes() function pointer.
1097  * Convert a character to its bytes.
1098  * Returns the length in bytes.
1099  */
1100     int
1101 latin_char2bytes(int c, char_u *buf)
1102 {
1103     buf[0] = c;
1104     return 1;
1105 }
1106 
1107     static int
1108 dbcs_char2bytes(int c, char_u *buf)
1109 {
1110     if (c >= 0x100)
1111     {
1112 	buf[0] = (unsigned)c >> 8;
1113 	buf[1] = c;
1114 	/* Never use a NUL byte, it causes lots of trouble.  It's an invalid
1115 	 * character anyway. */
1116 	if (buf[1] == NUL)
1117 	    buf[1] = '\n';
1118 	return 2;
1119     }
1120     buf[0] = c;
1121     return 1;
1122 }
1123 
1124 /*
1125  * mb_ptr2len() function pointer.
1126  * Get byte length of character at "*p" but stop at a NUL.
1127  * For UTF-8 this includes following composing characters.
1128  * Returns 0 when *p is NUL.
1129  */
1130     int
1131 latin_ptr2len(char_u *p)
1132 {
1133  return MB_BYTE2LEN(*p);
1134 }
1135 
1136     static int
1137 dbcs_ptr2len(
1138     char_u	*p)
1139 {
1140     int		len;
1141 
1142     /* Check if second byte is not missing. */
1143     len = MB_BYTE2LEN(*p);
1144     if (len == 2 && p[1] == NUL)
1145 	len = 1;
1146     return len;
1147 }
1148 
1149 /*
1150  * mb_ptr2len_len() function pointer.
1151  * Like mb_ptr2len(), but limit to read "size" bytes.
1152  * Returns 0 for an empty string.
1153  * Returns 1 for an illegal char or an incomplete byte sequence.
1154  */
1155     int
1156 latin_ptr2len_len(char_u *p, int size)
1157 {
1158     if (size < 1 || *p == NUL)
1159 	return 0;
1160     return 1;
1161 }
1162 
1163     static int
1164 dbcs_ptr2len_len(char_u *p, int size)
1165 {
1166     int		len;
1167 
1168     if (size < 1 || *p == NUL)
1169 	return 0;
1170     if (size == 1)
1171 	return 1;
1172     /* Check that second byte is not missing. */
1173     len = MB_BYTE2LEN(*p);
1174     if (len == 2 && p[1] == NUL)
1175 	len = 1;
1176     return len;
1177 }
1178 
1179 struct interval
1180 {
1181     long first;
1182     long last;
1183 };
1184 
1185 /*
1186  * Return TRUE if "c" is in "table[size / sizeof(struct interval)]".
1187  */
1188     static int
1189 intable(struct interval *table, size_t size, int c)
1190 {
1191     int mid, bot, top;
1192 
1193     /* first quick check for Latin1 etc. characters */
1194     if (c < table[0].first)
1195 	return FALSE;
1196 
1197     /* binary search in table */
1198     bot = 0;
1199     top = (int)(size / sizeof(struct interval) - 1);
1200     while (top >= bot)
1201     {
1202 	mid = (bot + top) / 2;
1203 	if (table[mid].last < c)
1204 	    bot = mid + 1;
1205 	else if (table[mid].first > c)
1206 	    top = mid - 1;
1207 	else
1208 	    return TRUE;
1209     }
1210     return FALSE;
1211 }
1212 
1213 /* Sorted list of non-overlapping intervals of East Asian Ambiguous
1214  * characters, generated with ../runtime/tools/unicode.vim. */
1215 static struct interval ambiguous[] =
1216 {
1217     {0x00a1, 0x00a1},
1218     {0x00a4, 0x00a4},
1219     {0x00a7, 0x00a8},
1220     {0x00aa, 0x00aa},
1221     {0x00ad, 0x00ae},
1222     {0x00b0, 0x00b4},
1223     {0x00b6, 0x00ba},
1224     {0x00bc, 0x00bf},
1225     {0x00c6, 0x00c6},
1226     {0x00d0, 0x00d0},
1227     {0x00d7, 0x00d8},
1228     {0x00de, 0x00e1},
1229     {0x00e6, 0x00e6},
1230     {0x00e8, 0x00ea},
1231     {0x00ec, 0x00ed},
1232     {0x00f0, 0x00f0},
1233     {0x00f2, 0x00f3},
1234     {0x00f7, 0x00fa},
1235     {0x00fc, 0x00fc},
1236     {0x00fe, 0x00fe},
1237     {0x0101, 0x0101},
1238     {0x0111, 0x0111},
1239     {0x0113, 0x0113},
1240     {0x011b, 0x011b},
1241     {0x0126, 0x0127},
1242     {0x012b, 0x012b},
1243     {0x0131, 0x0133},
1244     {0x0138, 0x0138},
1245     {0x013f, 0x0142},
1246     {0x0144, 0x0144},
1247     {0x0148, 0x014b},
1248     {0x014d, 0x014d},
1249     {0x0152, 0x0153},
1250     {0x0166, 0x0167},
1251     {0x016b, 0x016b},
1252     {0x01ce, 0x01ce},
1253     {0x01d0, 0x01d0},
1254     {0x01d2, 0x01d2},
1255     {0x01d4, 0x01d4},
1256     {0x01d6, 0x01d6},
1257     {0x01d8, 0x01d8},
1258     {0x01da, 0x01da},
1259     {0x01dc, 0x01dc},
1260     {0x0251, 0x0251},
1261     {0x0261, 0x0261},
1262     {0x02c4, 0x02c4},
1263     {0x02c7, 0x02c7},
1264     {0x02c9, 0x02cb},
1265     {0x02cd, 0x02cd},
1266     {0x02d0, 0x02d0},
1267     {0x02d8, 0x02db},
1268     {0x02dd, 0x02dd},
1269     {0x02df, 0x02df},
1270     {0x0300, 0x036f},
1271     {0x0391, 0x03a1},
1272     {0x03a3, 0x03a9},
1273     {0x03b1, 0x03c1},
1274     {0x03c3, 0x03c9},
1275     {0x0401, 0x0401},
1276     {0x0410, 0x044f},
1277     {0x0451, 0x0451},
1278     {0x2010, 0x2010},
1279     {0x2013, 0x2016},
1280     {0x2018, 0x2019},
1281     {0x201c, 0x201d},
1282     {0x2020, 0x2022},
1283     {0x2024, 0x2027},
1284     {0x2030, 0x2030},
1285     {0x2032, 0x2033},
1286     {0x2035, 0x2035},
1287     {0x203b, 0x203b},
1288     {0x203e, 0x203e},
1289     {0x2074, 0x2074},
1290     {0x207f, 0x207f},
1291     {0x2081, 0x2084},
1292     {0x20ac, 0x20ac},
1293     {0x2103, 0x2103},
1294     {0x2105, 0x2105},
1295     {0x2109, 0x2109},
1296     {0x2113, 0x2113},
1297     {0x2116, 0x2116},
1298     {0x2121, 0x2122},
1299     {0x2126, 0x2126},
1300     {0x212b, 0x212b},
1301     {0x2153, 0x2154},
1302     {0x215b, 0x215e},
1303     {0x2160, 0x216b},
1304     {0x2170, 0x2179},
1305     {0x2189, 0x2189},
1306     {0x2190, 0x2199},
1307     {0x21b8, 0x21b9},
1308     {0x21d2, 0x21d2},
1309     {0x21d4, 0x21d4},
1310     {0x21e7, 0x21e7},
1311     {0x2200, 0x2200},
1312     {0x2202, 0x2203},
1313     {0x2207, 0x2208},
1314     {0x220b, 0x220b},
1315     {0x220f, 0x220f},
1316     {0x2211, 0x2211},
1317     {0x2215, 0x2215},
1318     {0x221a, 0x221a},
1319     {0x221d, 0x2220},
1320     {0x2223, 0x2223},
1321     {0x2225, 0x2225},
1322     {0x2227, 0x222c},
1323     {0x222e, 0x222e},
1324     {0x2234, 0x2237},
1325     {0x223c, 0x223d},
1326     {0x2248, 0x2248},
1327     {0x224c, 0x224c},
1328     {0x2252, 0x2252},
1329     {0x2260, 0x2261},
1330     {0x2264, 0x2267},
1331     {0x226a, 0x226b},
1332     {0x226e, 0x226f},
1333     {0x2282, 0x2283},
1334     {0x2286, 0x2287},
1335     {0x2295, 0x2295},
1336     {0x2299, 0x2299},
1337     {0x22a5, 0x22a5},
1338     {0x22bf, 0x22bf},
1339     {0x2312, 0x2312},
1340     {0x2460, 0x24e9},
1341     {0x24eb, 0x254b},
1342     {0x2550, 0x2573},
1343     {0x2580, 0x258f},
1344     {0x2592, 0x2595},
1345     {0x25a0, 0x25a1},
1346     {0x25a3, 0x25a9},
1347     {0x25b2, 0x25b3},
1348     {0x25b6, 0x25b7},
1349     {0x25bc, 0x25bd},
1350     {0x25c0, 0x25c1},
1351     {0x25c6, 0x25c8},
1352     {0x25cb, 0x25cb},
1353     {0x25ce, 0x25d1},
1354     {0x25e2, 0x25e5},
1355     {0x25ef, 0x25ef},
1356     {0x2605, 0x2606},
1357     {0x2609, 0x2609},
1358     {0x260e, 0x260f},
1359     {0x261c, 0x261c},
1360     {0x261e, 0x261e},
1361     {0x2640, 0x2640},
1362     {0x2642, 0x2642},
1363     {0x2660, 0x2661},
1364     {0x2663, 0x2665},
1365     {0x2667, 0x266a},
1366     {0x266c, 0x266d},
1367     {0x266f, 0x266f},
1368     {0x269e, 0x269f},
1369     {0x26bf, 0x26bf},
1370     {0x26c6, 0x26cd},
1371     {0x26cf, 0x26d3},
1372     {0x26d5, 0x26e1},
1373     {0x26e3, 0x26e3},
1374     {0x26e8, 0x26e9},
1375     {0x26eb, 0x26f1},
1376     {0x26f4, 0x26f4},
1377     {0x26f6, 0x26f9},
1378     {0x26fb, 0x26fc},
1379     {0x26fe, 0x26ff},
1380     {0x273d, 0x273d},
1381     {0x2776, 0x277f},
1382     {0x2b56, 0x2b59},
1383     {0x3248, 0x324f},
1384     {0xe000, 0xf8ff},
1385     {0xfe00, 0xfe0f},
1386     {0xfffd, 0xfffd},
1387     {0x1f100, 0x1f10a},
1388     {0x1f110, 0x1f12d},
1389     {0x1f130, 0x1f169},
1390     {0x1f170, 0x1f18d},
1391     {0x1f18f, 0x1f190},
1392     {0x1f19b, 0x1f1ac},
1393     {0xe0100, 0xe01ef},
1394     {0xf0000, 0xffffd},
1395     {0x100000, 0x10fffd}
1396 };
1397 
1398 /*
1399  * For UTF-8 character "c" return 2 for a double-width character, 1 for others.
1400  * Returns 4 or 6 for an unprintable character.
1401  * Is only correct for characters >= 0x80.
1402  * When p_ambw is "double", return 2 for a character with East Asian Width
1403  * class 'A'(mbiguous).
1404  */
1405     int
1406 utf_char2cells(int c)
1407 {
1408     /* Sorted list of non-overlapping intervals of East Asian double width
1409      * characters, generated with ../runtime/tools/unicode.vim. */
1410     static struct interval doublewidth[] =
1411     {
1412 	{0x1100, 0x115f},
1413 	{0x231a, 0x231b},
1414 	{0x2329, 0x232a},
1415 	{0x23e9, 0x23ec},
1416 	{0x23f0, 0x23f0},
1417 	{0x23f3, 0x23f3},
1418 	{0x25fd, 0x25fe},
1419 	{0x2614, 0x2615},
1420 	{0x2648, 0x2653},
1421 	{0x267f, 0x267f},
1422 	{0x2693, 0x2693},
1423 	{0x26a1, 0x26a1},
1424 	{0x26aa, 0x26ab},
1425 	{0x26bd, 0x26be},
1426 	{0x26c4, 0x26c5},
1427 	{0x26ce, 0x26ce},
1428 	{0x26d4, 0x26d4},
1429 	{0x26ea, 0x26ea},
1430 	{0x26f2, 0x26f3},
1431 	{0x26f5, 0x26f5},
1432 	{0x26fa, 0x26fa},
1433 	{0x26fd, 0x26fd},
1434 	{0x2705, 0x2705},
1435 	{0x270a, 0x270b},
1436 	{0x2728, 0x2728},
1437 	{0x274c, 0x274c},
1438 	{0x274e, 0x274e},
1439 	{0x2753, 0x2755},
1440 	{0x2757, 0x2757},
1441 	{0x2795, 0x2797},
1442 	{0x27b0, 0x27b0},
1443 	{0x27bf, 0x27bf},
1444 	{0x2b1b, 0x2b1c},
1445 	{0x2b50, 0x2b50},
1446 	{0x2b55, 0x2b55},
1447 	{0x2e80, 0x2e99},
1448 	{0x2e9b, 0x2ef3},
1449 	{0x2f00, 0x2fd5},
1450 	{0x2ff0, 0x2ffb},
1451 	{0x3000, 0x303e},
1452 	{0x3041, 0x3096},
1453 	{0x3099, 0x30ff},
1454 	{0x3105, 0x312d},
1455 	{0x3131, 0x318e},
1456 	{0x3190, 0x31ba},
1457 	{0x31c0, 0x31e3},
1458 	{0x31f0, 0x321e},
1459 	{0x3220, 0x3247},
1460 	{0x3250, 0x32fe},
1461 	{0x3300, 0x4dbf},
1462 	{0x4e00, 0xa48c},
1463 	{0xa490, 0xa4c6},
1464 	{0xa960, 0xa97c},
1465 	{0xac00, 0xd7a3},
1466 	{0xf900, 0xfaff},
1467 	{0xfe10, 0xfe19},
1468 	{0xfe30, 0xfe52},
1469 	{0xfe54, 0xfe66},
1470 	{0xfe68, 0xfe6b},
1471 	{0xff01, 0xff60},
1472 	{0xffe0, 0xffe6},
1473 	{0x16fe0, 0x16fe0},
1474 	{0x17000, 0x187ec},
1475 	{0x18800, 0x18af2},
1476 	{0x1b000, 0x1b001},
1477 	{0x1f004, 0x1f004},
1478 	{0x1f0cf, 0x1f0cf},
1479 	{0x1f18e, 0x1f18e},
1480 	{0x1f191, 0x1f19a},
1481 	{0x1f200, 0x1f202},
1482 	{0x1f210, 0x1f23b},
1483 	{0x1f240, 0x1f248},
1484 	{0x1f250, 0x1f251},
1485 	{0x1f300, 0x1f320},
1486 	{0x1f32d, 0x1f335},
1487 	{0x1f337, 0x1f37c},
1488 	{0x1f37e, 0x1f393},
1489 	{0x1f3a0, 0x1f3ca},
1490 	{0x1f3cf, 0x1f3d3},
1491 	{0x1f3e0, 0x1f3f0},
1492 	{0x1f3f4, 0x1f3f4},
1493 	{0x1f3f8, 0x1f43e},
1494 	{0x1f440, 0x1f440},
1495 	{0x1f442, 0x1f4fc},
1496 	{0x1f4ff, 0x1f53d},
1497 	{0x1f54b, 0x1f54e},
1498 	{0x1f550, 0x1f567},
1499 	{0x1f57a, 0x1f57a},
1500 	{0x1f595, 0x1f596},
1501 	{0x1f5a4, 0x1f5a4},
1502 	{0x1f5fb, 0x1f64f},
1503 	{0x1f680, 0x1f6c5},
1504 	{0x1f6cc, 0x1f6cc},
1505 	{0x1f6d0, 0x1f6d2},
1506 	{0x1f6eb, 0x1f6ec},
1507 	{0x1f6f4, 0x1f6f6},
1508 	{0x1f910, 0x1f91e},
1509 	{0x1f920, 0x1f927},
1510 	{0x1f930, 0x1f930},
1511 	{0x1f933, 0x1f93e},
1512 	{0x1f940, 0x1f94b},
1513 	{0x1f950, 0x1f95e},
1514 	{0x1f980, 0x1f991},
1515 	{0x1f9c0, 0x1f9c0},
1516 	{0x20000, 0x2fffd},
1517 	{0x30000, 0x3fffd}
1518     };
1519 
1520     /* Sorted list of non-overlapping intervals of Emoji characters that don't
1521      * have ambiguous or double width,
1522      * based on http://unicode.org/emoji/charts/emoji-list.html */
1523     static struct interval emoji_width[] =
1524     {
1525 	{0x1f004, 0x1f004},
1526 	{0x1f0cf, 0x1f0cf},
1527 	{0x1f1e6, 0x1f1ff},
1528 	{0x1f300, 0x1f320},
1529 	{0x1f330, 0x1f335},
1530 	{0x1f337, 0x1f37c},
1531 	{0x1f380, 0x1f393},
1532 	{0x1f3a0, 0x1f3c4},
1533 	{0x1f3c6, 0x1f3ca},
1534 	{0x1f3e0, 0x1f3f0},
1535 	{0x1f400, 0x1f43e},
1536 	{0x1f440, 0x1f440},
1537 	{0x1f442, 0x1f4f7},
1538 	{0x1f4f9, 0x1f4fc},
1539 	{0x1f500, 0x1f53d},
1540 	{0x1f550, 0x1f567},
1541 	{0x1f5fb, 0x1f640},
1542 	{0x1f645, 0x1f64f},
1543 	{0x1f680, 0x1f6c5}
1544     };
1545 
1546     if (c >= 0x100)
1547     {
1548 #ifdef USE_WCHAR_FUNCTIONS
1549 	/*
1550 	 * Assume the library function wcwidth() works better than our own
1551 	 * stuff.  It should return 1 for ambiguous width chars!
1552 	 */
1553 	int	n = wcwidth(c);
1554 
1555 	if (n < 0)
1556 	    return 6;		/* unprintable, displays <xxxx> */
1557 	if (n > 1)
1558 	    return n;
1559 #else
1560 	if (!utf_printable(c))
1561 	    return 6;		/* unprintable, displays <xxxx> */
1562 	if (intable(doublewidth, sizeof(doublewidth), c))
1563 	    return 2;
1564 #endif
1565 	if (p_emoji && intable(emoji_width, sizeof(emoji_width), c))
1566 	    return 2;
1567     }
1568 
1569     /* Characters below 0x100 are influenced by 'isprint' option */
1570     else if (c >= 0x80 && !vim_isprintc(c))
1571 	return 4;		/* unprintable, displays <xx> */
1572 
1573     if (c >= 0x80 && *p_ambw == 'd' && intable(ambiguous, sizeof(ambiguous), c))
1574 	return 2;
1575 
1576     return 1;
1577 }
1578 
1579 /*
1580  * mb_ptr2cells() function pointer.
1581  * Return the number of display cells character at "*p" occupies.
1582  * This doesn't take care of unprintable characters, use ptr2cells() for that.
1583  */
1584     int
1585 latin_ptr2cells(char_u *p UNUSED)
1586 {
1587     return 1;
1588 }
1589 
1590     int
1591 utf_ptr2cells(
1592     char_u	*p)
1593 {
1594     int		c;
1595 
1596     /* Need to convert to a wide character. */
1597     if (*p >= 0x80)
1598     {
1599 	c = utf_ptr2char(p);
1600 	/* An illegal byte is displayed as <xx>. */
1601 	if (utf_ptr2len(p) == 1 || c == NUL)
1602 	    return 4;
1603 	/* If the char is ASCII it must be an overlong sequence. */
1604 	if (c < 0x80)
1605 	    return char2cells(c);
1606 	return utf_char2cells(c);
1607     }
1608     return 1;
1609 }
1610 
1611     int
1612 dbcs_ptr2cells(char_u *p)
1613 {
1614     /* Number of cells is equal to number of bytes, except for euc-jp when
1615      * the first byte is 0x8e. */
1616     if (enc_dbcs == DBCS_JPNU && *p == 0x8e)
1617 	return 1;
1618     return MB_BYTE2LEN(*p);
1619 }
1620 
1621 /*
1622  * mb_ptr2cells_len() function pointer.
1623  * Like mb_ptr2cells(), but limit string length to "size".
1624  * For an empty string or truncated character returns 1.
1625  */
1626     int
1627 latin_ptr2cells_len(char_u *p UNUSED, int size UNUSED)
1628 {
1629     return 1;
1630 }
1631 
1632     static int
1633 utf_ptr2cells_len(char_u *p, int size)
1634 {
1635     int		c;
1636 
1637     /* Need to convert to a wide character. */
1638     if (size > 0 && *p >= 0x80)
1639     {
1640 	if (utf_ptr2len_len(p, size) < utf8len_tab[*p])
1641 	    return 1;  /* truncated */
1642 	c = utf_ptr2char(p);
1643 	/* An illegal byte is displayed as <xx>. */
1644 	if (utf_ptr2len(p) == 1 || c == NUL)
1645 	    return 4;
1646 	/* If the char is ASCII it must be an overlong sequence. */
1647 	if (c < 0x80)
1648 	    return char2cells(c);
1649 	return utf_char2cells(c);
1650     }
1651     return 1;
1652 }
1653 
1654     static int
1655 dbcs_ptr2cells_len(char_u *p, int size)
1656 {
1657     /* Number of cells is equal to number of bytes, except for euc-jp when
1658      * the first byte is 0x8e. */
1659     if (size <= 1 || (enc_dbcs == DBCS_JPNU && *p == 0x8e))
1660 	return 1;
1661     return MB_BYTE2LEN(*p);
1662 }
1663 
1664 /*
1665  * mb_char2cells() function pointer.
1666  * Return the number of display cells character "c" occupies.
1667  * Only takes care of multi-byte chars, not "^C" and such.
1668  */
1669     int
1670 latin_char2cells(int c UNUSED)
1671 {
1672     return 1;
1673 }
1674 
1675     static int
1676 dbcs_char2cells(int c)
1677 {
1678     /* Number of cells is equal to number of bytes, except for euc-jp when
1679      * the first byte is 0x8e. */
1680     if (enc_dbcs == DBCS_JPNU && ((unsigned)c >> 8) == 0x8e)
1681 	return 1;
1682     /* use the first byte */
1683     return MB_BYTE2LEN((unsigned)c >> 8);
1684 }
1685 
1686 /*
1687  * Return the number of cells occupied by string "p".
1688  * Stop at a NUL character.  When "len" >= 0 stop at character "p[len]".
1689  */
1690     int
1691 mb_string2cells(char_u *p, int len)
1692 {
1693     int i;
1694     int clen = 0;
1695 
1696     for (i = 0; (len < 0 || i < len) && p[i] != NUL; i += (*mb_ptr2len)(p + i))
1697 	clen += (*mb_ptr2cells)(p + i);
1698     return clen;
1699 }
1700 
1701 /*
1702  * mb_off2cells() function pointer.
1703  * Return number of display cells for char at ScreenLines[off].
1704  * We make sure that the offset used is less than "max_off".
1705  */
1706     int
1707 latin_off2cells(unsigned off UNUSED, unsigned max_off UNUSED)
1708 {
1709     return 1;
1710 }
1711 
1712     int
1713 dbcs_off2cells(unsigned off, unsigned max_off)
1714 {
1715     /* never check beyond end of the line */
1716     if (off >= max_off)
1717 	return 1;
1718 
1719     /* Number of cells is equal to number of bytes, except for euc-jp when
1720      * the first byte is 0x8e. */
1721     if (enc_dbcs == DBCS_JPNU && ScreenLines[off] == 0x8e)
1722 	return 1;
1723     return MB_BYTE2LEN(ScreenLines[off]);
1724 }
1725 
1726     int
1727 utf_off2cells(unsigned off, unsigned max_off)
1728 {
1729     return (off + 1 < max_off && ScreenLines[off + 1] == 0) ? 2 : 1;
1730 }
1731 
1732 /*
1733  * mb_ptr2char() function pointer.
1734  * Convert a byte sequence into a character.
1735  */
1736     int
1737 latin_ptr2char(char_u *p)
1738 {
1739     return *p;
1740 }
1741 
1742     static int
1743 dbcs_ptr2char(char_u *p)
1744 {
1745     if (MB_BYTE2LEN(*p) > 1 && p[1] != NUL)
1746 	return (p[0] << 8) + p[1];
1747     return *p;
1748 }
1749 
1750 /*
1751  * Convert a UTF-8 byte sequence to a wide character.
1752  * If the sequence is illegal or truncated by a NUL the first byte is
1753  * returned.
1754  * Does not include composing characters, of course.
1755  */
1756     int
1757 utf_ptr2char(char_u *p)
1758 {
1759     int		len;
1760 
1761     if (p[0] < 0x80)	/* be quick for ASCII */
1762 	return p[0];
1763 
1764     len = utf8len_tab_zero[p[0]];
1765     if (len > 1 && (p[1] & 0xc0) == 0x80)
1766     {
1767 	if (len == 2)
1768 	    return ((p[0] & 0x1f) << 6) + (p[1] & 0x3f);
1769 	if ((p[2] & 0xc0) == 0x80)
1770 	{
1771 	    if (len == 3)
1772 		return ((p[0] & 0x0f) << 12) + ((p[1] & 0x3f) << 6)
1773 		    + (p[2] & 0x3f);
1774 	    if ((p[3] & 0xc0) == 0x80)
1775 	    {
1776 		if (len == 4)
1777 		    return ((p[0] & 0x07) << 18) + ((p[1] & 0x3f) << 12)
1778 			+ ((p[2] & 0x3f) << 6) + (p[3] & 0x3f);
1779 		if ((p[4] & 0xc0) == 0x80)
1780 		{
1781 		    if (len == 5)
1782 			return ((p[0] & 0x03) << 24) + ((p[1] & 0x3f) << 18)
1783 			    + ((p[2] & 0x3f) << 12) + ((p[3] & 0x3f) << 6)
1784 			    + (p[4] & 0x3f);
1785 		    if ((p[5] & 0xc0) == 0x80 && len == 6)
1786 			return ((p[0] & 0x01) << 30) + ((p[1] & 0x3f) << 24)
1787 			    + ((p[2] & 0x3f) << 18) + ((p[3] & 0x3f) << 12)
1788 			    + ((p[4] & 0x3f) << 6) + (p[5] & 0x3f);
1789 		}
1790 	    }
1791 	}
1792     }
1793     /* Illegal value, just return the first byte */
1794     return p[0];
1795 }
1796 
1797 /*
1798  * Convert a UTF-8 byte sequence to a wide character.
1799  * String is assumed to be terminated by NUL or after "n" bytes, whichever
1800  * comes first.
1801  * The function is safe in the sense that it never accesses memory beyond the
1802  * first "n" bytes of "s".
1803  *
1804  * On success, returns decoded codepoint, advances "s" to the beginning of
1805  * next character and decreases "n" accordingly.
1806  *
1807  * If end of string was reached, returns 0 and, if "n" > 0, advances "s" past
1808  * NUL byte.
1809  *
1810  * If byte sequence is illegal or incomplete, returns -1 and does not advance
1811  * "s".
1812  */
1813     static int
1814 utf_safe_read_char_adv(char_u **s, size_t *n)
1815 {
1816     int		c, k;
1817 
1818     if (*n == 0) /* end of buffer */
1819 	return 0;
1820 
1821     k = utf8len_tab_zero[**s];
1822 
1823     if (k == 1)
1824     {
1825 	/* ASCII character or NUL */
1826 	(*n)--;
1827 	return *(*s)++;
1828     }
1829 
1830     if ((size_t)k <= *n)
1831     {
1832 	/* We have a multibyte sequence and it isn't truncated by buffer
1833 	 * limits so utf_ptr2char() is safe to use. Or the first byte is
1834 	 * illegal (k=0), and it's also safe to use utf_ptr2char(). */
1835 	c = utf_ptr2char(*s);
1836 
1837 	/* On failure, utf_ptr2char() returns the first byte, so here we
1838 	 * check equality with the first byte. The only non-ASCII character
1839 	 * which equals the first byte of its own UTF-8 representation is
1840 	 * U+00C3 (UTF-8: 0xC3 0x83), so need to check that special case too.
1841 	 * It's safe even if n=1, else we would have k=2 > n. */
1842 	if (c != (int)(**s) || (c == 0xC3 && (*s)[1] == 0x83))
1843 	{
1844 	    /* byte sequence was successfully decoded */
1845 	    *s += k;
1846 	    *n -= k;
1847 	    return c;
1848 	}
1849     }
1850 
1851     /* byte sequence is incomplete or illegal */
1852     return -1;
1853 }
1854 
1855 /*
1856  * Get character at **pp and advance *pp to the next character.
1857  * Note: composing characters are skipped!
1858  */
1859     int
1860 mb_ptr2char_adv(char_u **pp)
1861 {
1862     int		c;
1863 
1864     c = (*mb_ptr2char)(*pp);
1865     *pp += (*mb_ptr2len)(*pp);
1866     return c;
1867 }
1868 
1869 /*
1870  * Get character at **pp and advance *pp to the next character.
1871  * Note: composing characters are returned as separate characters.
1872  */
1873     int
1874 mb_cptr2char_adv(char_u **pp)
1875 {
1876     int		c;
1877 
1878     c = (*mb_ptr2char)(*pp);
1879     if (enc_utf8)
1880 	*pp += utf_ptr2len(*pp);
1881     else
1882 	*pp += (*mb_ptr2len)(*pp);
1883     return c;
1884 }
1885 
1886 #if defined(FEAT_ARABIC) || defined(PROTO)
1887 /*
1888  * Check whether we are dealing with Arabic combining characters.
1889  * Note: these are NOT really composing characters!
1890  */
1891     int
1892 arabic_combine(
1893     int		one,	    /* first character */
1894     int		two)	    /* character just after "one" */
1895 {
1896     if (one == a_LAM)
1897 	return arabic_maycombine(two);
1898     return FALSE;
1899 }
1900 
1901 /*
1902  * Check whether we are dealing with a character that could be regarded as an
1903  * Arabic combining character, need to check the character before this.
1904  */
1905     int
1906 arabic_maycombine(int two)
1907 {
1908     if (p_arshape && !p_tbidi)
1909 	return (two == a_ALEF_MADDA
1910 		    || two == a_ALEF_HAMZA_ABOVE
1911 		    || two == a_ALEF_HAMZA_BELOW
1912 		    || two == a_ALEF);
1913     return FALSE;
1914 }
1915 
1916 /*
1917  * Check if the character pointed to by "p2" is a composing character when it
1918  * comes after "p1".  For Arabic sometimes "ab" is replaced with "c", which
1919  * behaves like a composing character.
1920  */
1921     int
1922 utf_composinglike(char_u *p1, char_u *p2)
1923 {
1924     int		c2;
1925 
1926     c2 = utf_ptr2char(p2);
1927     if (utf_iscomposing(c2))
1928 	return TRUE;
1929     if (!arabic_maycombine(c2))
1930 	return FALSE;
1931     return arabic_combine(utf_ptr2char(p1), c2);
1932 }
1933 #endif
1934 
1935 /*
1936  * Convert a UTF-8 byte string to a wide character.  Also get up to MAX_MCO
1937  * composing characters.
1938  */
1939     int
1940 utfc_ptr2char(
1941     char_u	*p,
1942     int		*pcc)	/* return: composing chars, last one is 0 */
1943 {
1944     int		len;
1945     int		c;
1946     int		cc;
1947     int		i = 0;
1948 
1949     c = utf_ptr2char(p);
1950     len = utf_ptr2len(p);
1951 
1952     /* Only accept a composing char when the first char isn't illegal. */
1953     if ((len > 1 || *p < 0x80)
1954 	    && p[len] >= 0x80
1955 	    && UTF_COMPOSINGLIKE(p, p + len))
1956     {
1957 	cc = utf_ptr2char(p + len);
1958 	for (;;)
1959 	{
1960 	    pcc[i++] = cc;
1961 	    if (i == MAX_MCO)
1962 		break;
1963 	    len += utf_ptr2len(p + len);
1964 	    if (p[len] < 0x80 || !utf_iscomposing(cc = utf_ptr2char(p + len)))
1965 		break;
1966 	}
1967     }
1968 
1969     if (i < MAX_MCO)	/* last composing char must be 0 */
1970 	pcc[i] = 0;
1971 
1972     return c;
1973 }
1974 
1975 /*
1976  * Convert a UTF-8 byte string to a wide character.  Also get up to MAX_MCO
1977  * composing characters.  Use no more than p[maxlen].
1978  */
1979     int
1980 utfc_ptr2char_len(
1981     char_u	*p,
1982     int		*pcc,	/* return: composing chars, last one is 0 */
1983     int		maxlen)
1984 {
1985     int		len;
1986     int		c;
1987     int		cc;
1988     int		i = 0;
1989 
1990     c = utf_ptr2char(p);
1991     len = utf_ptr2len_len(p, maxlen);
1992     /* Only accept a composing char when the first char isn't illegal. */
1993     if ((len > 1 || *p < 0x80)
1994 	    && len < maxlen
1995 	    && p[len] >= 0x80
1996 	    && UTF_COMPOSINGLIKE(p, p + len))
1997     {
1998 	cc = utf_ptr2char(p + len);
1999 	for (;;)
2000 	{
2001 	    pcc[i++] = cc;
2002 	    if (i == MAX_MCO)
2003 		break;
2004 	    len += utf_ptr2len_len(p + len, maxlen - len);
2005 	    if (len >= maxlen
2006 		    || p[len] < 0x80
2007 		    || !utf_iscomposing(cc = utf_ptr2char(p + len)))
2008 		break;
2009 	}
2010     }
2011 
2012     if (i < MAX_MCO)	/* last composing char must be 0 */
2013 	pcc[i] = 0;
2014 
2015     return c;
2016 }
2017 
2018 /*
2019  * Convert the character at screen position "off" to a sequence of bytes.
2020  * Includes the composing characters.
2021  * "buf" must at least have the length MB_MAXBYTES + 1.
2022  * Only to be used when ScreenLinesUC[off] != 0.
2023  * Returns the produced number of bytes.
2024  */
2025     int
2026 utfc_char2bytes(int off, char_u *buf)
2027 {
2028     int		len;
2029     int		i;
2030 
2031     len = utf_char2bytes(ScreenLinesUC[off], buf);
2032     for (i = 0; i < Screen_mco; ++i)
2033     {
2034 	if (ScreenLinesC[i][off] == 0)
2035 	    break;
2036 	len += utf_char2bytes(ScreenLinesC[i][off], buf + len);
2037     }
2038     return len;
2039 }
2040 
2041 /*
2042  * Get the length of a UTF-8 byte sequence, not including any following
2043  * composing characters.
2044  * Returns 0 for "".
2045  * Returns 1 for an illegal byte sequence.
2046  */
2047     int
2048 utf_ptr2len(char_u *p)
2049 {
2050     int		len;
2051     int		i;
2052 
2053     if (*p == NUL)
2054 	return 0;
2055     len = utf8len_tab[*p];
2056     for (i = 1; i < len; ++i)
2057 	if ((p[i] & 0xc0) != 0x80)
2058 	    return 1;
2059     return len;
2060 }
2061 
2062 /*
2063  * Return length of UTF-8 character, obtained from the first byte.
2064  * "b" must be between 0 and 255!
2065  * Returns 1 for an invalid first byte value.
2066  */
2067     int
2068 utf_byte2len(int b)
2069 {
2070     return utf8len_tab[b];
2071 }
2072 
2073 /*
2074  * Get the length of UTF-8 byte sequence "p[size]".  Does not include any
2075  * following composing characters.
2076  * Returns 1 for "".
2077  * Returns 1 for an illegal byte sequence (also in incomplete byte seq.).
2078  * Returns number > "size" for an incomplete byte sequence.
2079  * Never returns zero.
2080  */
2081     int
2082 utf_ptr2len_len(char_u *p, int size)
2083 {
2084     int		len;
2085     int		i;
2086     int		m;
2087 
2088     len = utf8len_tab[*p];
2089     if (len == 1)
2090 	return 1;	/* NUL, ascii or illegal lead byte */
2091     if (len > size)
2092 	m = size;	/* incomplete byte sequence. */
2093     else
2094 	m = len;
2095     for (i = 1; i < m; ++i)
2096 	if ((p[i] & 0xc0) != 0x80)
2097 	    return 1;
2098     return len;
2099 }
2100 
2101 /*
2102  * Return the number of bytes the UTF-8 encoding of the character at "p" takes.
2103  * This includes following composing characters.
2104  */
2105     int
2106 utfc_ptr2len(char_u *p)
2107 {
2108     int		len;
2109     int		b0 = *p;
2110 #ifdef FEAT_ARABIC
2111     int		prevlen;
2112 #endif
2113 
2114     if (b0 == NUL)
2115 	return 0;
2116     if (b0 < 0x80 && p[1] < 0x80)	/* be quick for ASCII */
2117 	return 1;
2118 
2119     /* Skip over first UTF-8 char, stopping at a NUL byte. */
2120     len = utf_ptr2len(p);
2121 
2122     /* Check for illegal byte. */
2123     if (len == 1 && b0 >= 0x80)
2124 	return 1;
2125 
2126     /*
2127      * Check for composing characters.  We can handle only the first six, but
2128      * skip all of them (otherwise the cursor would get stuck).
2129      */
2130 #ifdef FEAT_ARABIC
2131     prevlen = 0;
2132 #endif
2133     for (;;)
2134     {
2135 	if (p[len] < 0x80 || !UTF_COMPOSINGLIKE(p + prevlen, p + len))
2136 	    return len;
2137 
2138 	/* Skip over composing char */
2139 #ifdef FEAT_ARABIC
2140 	prevlen = len;
2141 #endif
2142 	len += utf_ptr2len(p + len);
2143     }
2144 }
2145 
2146 /*
2147  * Return the number of bytes the UTF-8 encoding of the character at "p[size]"
2148  * takes.  This includes following composing characters.
2149  * Returns 0 for an empty string.
2150  * Returns 1 for an illegal char or an incomplete byte sequence.
2151  */
2152     int
2153 utfc_ptr2len_len(char_u *p, int size)
2154 {
2155     int		len;
2156 #ifdef FEAT_ARABIC
2157     int		prevlen;
2158 #endif
2159 
2160     if (size < 1 || *p == NUL)
2161 	return 0;
2162     if (p[0] < 0x80 && (size == 1 || p[1] < 0x80)) /* be quick for ASCII */
2163 	return 1;
2164 
2165     /* Skip over first UTF-8 char, stopping at a NUL byte. */
2166     len = utf_ptr2len_len(p, size);
2167 
2168     /* Check for illegal byte and incomplete byte sequence. */
2169     if ((len == 1 && p[0] >= 0x80) || len > size)
2170 	return 1;
2171 
2172     /*
2173      * Check for composing characters.  We can handle only the first six, but
2174      * skip all of them (otherwise the cursor would get stuck).
2175      */
2176 #ifdef FEAT_ARABIC
2177     prevlen = 0;
2178 #endif
2179     while (len < size)
2180     {
2181 	int	len_next_char;
2182 
2183 	if (p[len] < 0x80)
2184 	    break;
2185 
2186 	/*
2187 	 * Next character length should not go beyond size to ensure that
2188 	 * UTF_COMPOSINGLIKE(...) does not read beyond size.
2189 	 */
2190 	len_next_char = utf_ptr2len_len(p + len, size - len);
2191 	if (len_next_char > size - len)
2192 	    break;
2193 
2194 	if (!UTF_COMPOSINGLIKE(p + prevlen, p + len))
2195 	    break;
2196 
2197 	/* Skip over composing char */
2198 #ifdef FEAT_ARABIC
2199 	prevlen = len;
2200 #endif
2201 	len += len_next_char;
2202     }
2203     return len;
2204 }
2205 
2206 /*
2207  * Return the number of bytes the UTF-8 encoding of character "c" takes.
2208  * This does not include composing characters.
2209  */
2210     int
2211 utf_char2len(int c)
2212 {
2213     if (c < 0x80)
2214 	return 1;
2215     if (c < 0x800)
2216 	return 2;
2217     if (c < 0x10000)
2218 	return 3;
2219     if (c < 0x200000)
2220 	return 4;
2221     if (c < 0x4000000)
2222 	return 5;
2223     return 6;
2224 }
2225 
2226 /*
2227  * Convert Unicode character "c" to UTF-8 string in "buf[]".
2228  * Returns the number of bytes.
2229  * This does not include composing characters.
2230  */
2231     int
2232 utf_char2bytes(int c, char_u *buf)
2233 {
2234     if (c < 0x80)		/* 7 bits */
2235     {
2236 	buf[0] = c;
2237 	return 1;
2238     }
2239     if (c < 0x800)		/* 11 bits */
2240     {
2241 	buf[0] = 0xc0 + ((unsigned)c >> 6);
2242 	buf[1] = 0x80 + (c & 0x3f);
2243 	return 2;
2244     }
2245     if (c < 0x10000)		/* 16 bits */
2246     {
2247 	buf[0] = 0xe0 + ((unsigned)c >> 12);
2248 	buf[1] = 0x80 + (((unsigned)c >> 6) & 0x3f);
2249 	buf[2] = 0x80 + (c & 0x3f);
2250 	return 3;
2251     }
2252     if (c < 0x200000)		/* 21 bits */
2253     {
2254 	buf[0] = 0xf0 + ((unsigned)c >> 18);
2255 	buf[1] = 0x80 + (((unsigned)c >> 12) & 0x3f);
2256 	buf[2] = 0x80 + (((unsigned)c >> 6) & 0x3f);
2257 	buf[3] = 0x80 + (c & 0x3f);
2258 	return 4;
2259     }
2260     if (c < 0x4000000)		/* 26 bits */
2261     {
2262 	buf[0] = 0xf8 + ((unsigned)c >> 24);
2263 	buf[1] = 0x80 + (((unsigned)c >> 18) & 0x3f);
2264 	buf[2] = 0x80 + (((unsigned)c >> 12) & 0x3f);
2265 	buf[3] = 0x80 + (((unsigned)c >> 6) & 0x3f);
2266 	buf[4] = 0x80 + (c & 0x3f);
2267 	return 5;
2268     }
2269 				/* 31 bits */
2270     buf[0] = 0xfc + ((unsigned)c >> 30);
2271     buf[1] = 0x80 + (((unsigned)c >> 24) & 0x3f);
2272     buf[2] = 0x80 + (((unsigned)c >> 18) & 0x3f);
2273     buf[3] = 0x80 + (((unsigned)c >> 12) & 0x3f);
2274     buf[4] = 0x80 + (((unsigned)c >> 6) & 0x3f);
2275     buf[5] = 0x80 + (c & 0x3f);
2276     return 6;
2277 }
2278 
2279 /*
2280  * Return TRUE if "c" is a composing UTF-8 character.  This means it will be
2281  * drawn on top of the preceding character.
2282  * Based on code from Markus Kuhn.
2283  */
2284     int
2285 utf_iscomposing(int c)
2286 {
2287     /* Sorted list of non-overlapping intervals.
2288      * Generated by ../runtime/tools/unicode.vim. */
2289     static struct interval combining[] =
2290     {
2291 	{0x0300, 0x036f},
2292 	{0x0483, 0x0489},
2293 	{0x0591, 0x05bd},
2294 	{0x05bf, 0x05bf},
2295 	{0x05c1, 0x05c2},
2296 	{0x05c4, 0x05c5},
2297 	{0x05c7, 0x05c7},
2298 	{0x0610, 0x061a},
2299 	{0x064b, 0x065f},
2300 	{0x0670, 0x0670},
2301 	{0x06d6, 0x06dc},
2302 	{0x06df, 0x06e4},
2303 	{0x06e7, 0x06e8},
2304 	{0x06ea, 0x06ed},
2305 	{0x0711, 0x0711},
2306 	{0x0730, 0x074a},
2307 	{0x07a6, 0x07b0},
2308 	{0x07eb, 0x07f3},
2309 	{0x0816, 0x0819},
2310 	{0x081b, 0x0823},
2311 	{0x0825, 0x0827},
2312 	{0x0829, 0x082d},
2313 	{0x0859, 0x085b},
2314 	{0x08d4, 0x08e1},
2315 	{0x08e3, 0x0903},
2316 	{0x093a, 0x093c},
2317 	{0x093e, 0x094f},
2318 	{0x0951, 0x0957},
2319 	{0x0962, 0x0963},
2320 	{0x0981, 0x0983},
2321 	{0x09bc, 0x09bc},
2322 	{0x09be, 0x09c4},
2323 	{0x09c7, 0x09c8},
2324 	{0x09cb, 0x09cd},
2325 	{0x09d7, 0x09d7},
2326 	{0x09e2, 0x09e3},
2327 	{0x0a01, 0x0a03},
2328 	{0x0a3c, 0x0a3c},
2329 	{0x0a3e, 0x0a42},
2330 	{0x0a47, 0x0a48},
2331 	{0x0a4b, 0x0a4d},
2332 	{0x0a51, 0x0a51},
2333 	{0x0a70, 0x0a71},
2334 	{0x0a75, 0x0a75},
2335 	{0x0a81, 0x0a83},
2336 	{0x0abc, 0x0abc},
2337 	{0x0abe, 0x0ac5},
2338 	{0x0ac7, 0x0ac9},
2339 	{0x0acb, 0x0acd},
2340 	{0x0ae2, 0x0ae3},
2341 	{0x0b01, 0x0b03},
2342 	{0x0b3c, 0x0b3c},
2343 	{0x0b3e, 0x0b44},
2344 	{0x0b47, 0x0b48},
2345 	{0x0b4b, 0x0b4d},
2346 	{0x0b56, 0x0b57},
2347 	{0x0b62, 0x0b63},
2348 	{0x0b82, 0x0b82},
2349 	{0x0bbe, 0x0bc2},
2350 	{0x0bc6, 0x0bc8},
2351 	{0x0bca, 0x0bcd},
2352 	{0x0bd7, 0x0bd7},
2353 	{0x0c00, 0x0c03},
2354 	{0x0c3e, 0x0c44},
2355 	{0x0c46, 0x0c48},
2356 	{0x0c4a, 0x0c4d},
2357 	{0x0c55, 0x0c56},
2358 	{0x0c62, 0x0c63},
2359 	{0x0c81, 0x0c83},
2360 	{0x0cbc, 0x0cbc},
2361 	{0x0cbe, 0x0cc4},
2362 	{0x0cc6, 0x0cc8},
2363 	{0x0cca, 0x0ccd},
2364 	{0x0cd5, 0x0cd6},
2365 	{0x0ce2, 0x0ce3},
2366 	{0x0d01, 0x0d03},
2367 	{0x0d3e, 0x0d44},
2368 	{0x0d46, 0x0d48},
2369 	{0x0d4a, 0x0d4d},
2370 	{0x0d57, 0x0d57},
2371 	{0x0d62, 0x0d63},
2372 	{0x0d82, 0x0d83},
2373 	{0x0dca, 0x0dca},
2374 	{0x0dcf, 0x0dd4},
2375 	{0x0dd6, 0x0dd6},
2376 	{0x0dd8, 0x0ddf},
2377 	{0x0df2, 0x0df3},
2378 	{0x0e31, 0x0e31},
2379 	{0x0e34, 0x0e3a},
2380 	{0x0e47, 0x0e4e},
2381 	{0x0eb1, 0x0eb1},
2382 	{0x0eb4, 0x0eb9},
2383 	{0x0ebb, 0x0ebc},
2384 	{0x0ec8, 0x0ecd},
2385 	{0x0f18, 0x0f19},
2386 	{0x0f35, 0x0f35},
2387 	{0x0f37, 0x0f37},
2388 	{0x0f39, 0x0f39},
2389 	{0x0f3e, 0x0f3f},
2390 	{0x0f71, 0x0f84},
2391 	{0x0f86, 0x0f87},
2392 	{0x0f8d, 0x0f97},
2393 	{0x0f99, 0x0fbc},
2394 	{0x0fc6, 0x0fc6},
2395 	{0x102b, 0x103e},
2396 	{0x1056, 0x1059},
2397 	{0x105e, 0x1060},
2398 	{0x1062, 0x1064},
2399 	{0x1067, 0x106d},
2400 	{0x1071, 0x1074},
2401 	{0x1082, 0x108d},
2402 	{0x108f, 0x108f},
2403 	{0x109a, 0x109d},
2404 	{0x135d, 0x135f},
2405 	{0x1712, 0x1714},
2406 	{0x1732, 0x1734},
2407 	{0x1752, 0x1753},
2408 	{0x1772, 0x1773},
2409 	{0x17b4, 0x17d3},
2410 	{0x17dd, 0x17dd},
2411 	{0x180b, 0x180d},
2412 	{0x1885, 0x1886},
2413 	{0x18a9, 0x18a9},
2414 	{0x1920, 0x192b},
2415 	{0x1930, 0x193b},
2416 	{0x1a17, 0x1a1b},
2417 	{0x1a55, 0x1a5e},
2418 	{0x1a60, 0x1a7c},
2419 	{0x1a7f, 0x1a7f},
2420 	{0x1ab0, 0x1abe},
2421 	{0x1b00, 0x1b04},
2422 	{0x1b34, 0x1b44},
2423 	{0x1b6b, 0x1b73},
2424 	{0x1b80, 0x1b82},
2425 	{0x1ba1, 0x1bad},
2426 	{0x1be6, 0x1bf3},
2427 	{0x1c24, 0x1c37},
2428 	{0x1cd0, 0x1cd2},
2429 	{0x1cd4, 0x1ce8},
2430 	{0x1ced, 0x1ced},
2431 	{0x1cf2, 0x1cf4},
2432 	{0x1cf8, 0x1cf9},
2433 	{0x1dc0, 0x1df5},
2434 	{0x1dfb, 0x1dff},
2435 	{0x20d0, 0x20f0},
2436 	{0x2cef, 0x2cf1},
2437 	{0x2d7f, 0x2d7f},
2438 	{0x2de0, 0x2dff},
2439 	{0x302a, 0x302f},
2440 	{0x3099, 0x309a},
2441 	{0xa66f, 0xa672},
2442 	{0xa674, 0xa67d},
2443 	{0xa69e, 0xa69f},
2444 	{0xa6f0, 0xa6f1},
2445 	{0xa802, 0xa802},
2446 	{0xa806, 0xa806},
2447 	{0xa80b, 0xa80b},
2448 	{0xa823, 0xa827},
2449 	{0xa880, 0xa881},
2450 	{0xa8b4, 0xa8c5},
2451 	{0xa8e0, 0xa8f1},
2452 	{0xa926, 0xa92d},
2453 	{0xa947, 0xa953},
2454 	{0xa980, 0xa983},
2455 	{0xa9b3, 0xa9c0},
2456 	{0xa9e5, 0xa9e5},
2457 	{0xaa29, 0xaa36},
2458 	{0xaa43, 0xaa43},
2459 	{0xaa4c, 0xaa4d},
2460 	{0xaa7b, 0xaa7d},
2461 	{0xaab0, 0xaab0},
2462 	{0xaab2, 0xaab4},
2463 	{0xaab7, 0xaab8},
2464 	{0xaabe, 0xaabf},
2465 	{0xaac1, 0xaac1},
2466 	{0xaaeb, 0xaaef},
2467 	{0xaaf5, 0xaaf6},
2468 	{0xabe3, 0xabea},
2469 	{0xabec, 0xabed},
2470 	{0xfb1e, 0xfb1e},
2471 	{0xfe00, 0xfe0f},
2472 	{0xfe20, 0xfe2f},
2473 	{0x101fd, 0x101fd},
2474 	{0x102e0, 0x102e0},
2475 	{0x10376, 0x1037a},
2476 	{0x10a01, 0x10a03},
2477 	{0x10a05, 0x10a06},
2478 	{0x10a0c, 0x10a0f},
2479 	{0x10a38, 0x10a3a},
2480 	{0x10a3f, 0x10a3f},
2481 	{0x10ae5, 0x10ae6},
2482 	{0x11000, 0x11002},
2483 	{0x11038, 0x11046},
2484 	{0x1107f, 0x11082},
2485 	{0x110b0, 0x110ba},
2486 	{0x11100, 0x11102},
2487 	{0x11127, 0x11134},
2488 	{0x11173, 0x11173},
2489 	{0x11180, 0x11182},
2490 	{0x111b3, 0x111c0},
2491 	{0x111ca, 0x111cc},
2492 	{0x1122c, 0x11237},
2493 	{0x1123e, 0x1123e},
2494 	{0x112df, 0x112ea},
2495 	{0x11300, 0x11303},
2496 	{0x1133c, 0x1133c},
2497 	{0x1133e, 0x11344},
2498 	{0x11347, 0x11348},
2499 	{0x1134b, 0x1134d},
2500 	{0x11357, 0x11357},
2501 	{0x11362, 0x11363},
2502 	{0x11366, 0x1136c},
2503 	{0x11370, 0x11374},
2504 	{0x11435, 0x11446},
2505 	{0x114b0, 0x114c3},
2506 	{0x115af, 0x115b5},
2507 	{0x115b8, 0x115c0},
2508 	{0x115dc, 0x115dd},
2509 	{0x11630, 0x11640},
2510 	{0x116ab, 0x116b7},
2511 	{0x1171d, 0x1172b},
2512 	{0x11c2f, 0x11c36},
2513 	{0x11c38, 0x11c3f},
2514 	{0x11c92, 0x11ca7},
2515 	{0x11ca9, 0x11cb6},
2516 	{0x16af0, 0x16af4},
2517 	{0x16b30, 0x16b36},
2518 	{0x16f51, 0x16f7e},
2519 	{0x16f8f, 0x16f92},
2520 	{0x1bc9d, 0x1bc9e},
2521 	{0x1d165, 0x1d169},
2522 	{0x1d16d, 0x1d172},
2523 	{0x1d17b, 0x1d182},
2524 	{0x1d185, 0x1d18b},
2525 	{0x1d1aa, 0x1d1ad},
2526 	{0x1d242, 0x1d244},
2527 	{0x1da00, 0x1da36},
2528 	{0x1da3b, 0x1da6c},
2529 	{0x1da75, 0x1da75},
2530 	{0x1da84, 0x1da84},
2531 	{0x1da9b, 0x1da9f},
2532 	{0x1daa1, 0x1daaf},
2533 	{0x1e000, 0x1e006},
2534 	{0x1e008, 0x1e018},
2535 	{0x1e01b, 0x1e021},
2536 	{0x1e023, 0x1e024},
2537 	{0x1e026, 0x1e02a},
2538 	{0x1e8d0, 0x1e8d6},
2539 	{0x1e944, 0x1e94a},
2540 	{0xe0100, 0xe01ef}
2541     };
2542 
2543     return intable(combining, sizeof(combining), c);
2544 }
2545 
2546 /*
2547  * Return TRUE for characters that can be displayed in a normal way.
2548  * Only for characters of 0x100 and above!
2549  */
2550     int
2551 utf_printable(int c)
2552 {
2553 #ifdef USE_WCHAR_FUNCTIONS
2554     /*
2555      * Assume the iswprint() library function works better than our own stuff.
2556      */
2557     return iswprint(c);
2558 #else
2559     /* Sorted list of non-overlapping intervals.
2560      * 0xd800-0xdfff is reserved for UTF-16, actually illegal. */
2561     static struct interval nonprint[] =
2562     {
2563 	{0x070f, 0x070f}, {0x180b, 0x180e}, {0x200b, 0x200f}, {0x202a, 0x202e},
2564 	{0x206a, 0x206f}, {0xd800, 0xdfff}, {0xfeff, 0xfeff}, {0xfff9, 0xfffb},
2565 	{0xfffe, 0xffff}
2566     };
2567 
2568     return !intable(nonprint, sizeof(nonprint), c);
2569 #endif
2570 }
2571 
2572 /* Sorted list of non-overlapping intervals of all Emoji characters,
2573  * based on http://unicode.org/emoji/charts/emoji-list.html */
2574 static struct interval emoji_all[] =
2575 {
2576     {0x203c, 0x203c},
2577     {0x2049, 0x2049},
2578     {0x2122, 0x2122},
2579     {0x2139, 0x2139},
2580     {0x2194, 0x2199},
2581     {0x21a9, 0x21aa},
2582     {0x231a, 0x231b},
2583     {0x2328, 0x2328},
2584     {0x23cf, 0x23cf},
2585     {0x23e9, 0x23f3},
2586     {0x24c2, 0x24c2},
2587     {0x25aa, 0x25ab},
2588     {0x25b6, 0x25b6},
2589     {0x25c0, 0x25c0},
2590     {0x25fb, 0x25fe},
2591     {0x2600, 0x2604},
2592     {0x260e, 0x260e},
2593     {0x2611, 0x2611},
2594     {0x2614, 0x2615},
2595     {0x2618, 0x2618},
2596     {0x261d, 0x261d},
2597     {0x2620, 0x2620},
2598     {0x2622, 0x2623},
2599     {0x2626, 0x2626},
2600     {0x262a, 0x262a},
2601     {0x262e, 0x262f},
2602     {0x2638, 0x263a},
2603     {0x2648, 0x2653},
2604     {0x2660, 0x2660},
2605     {0x2663, 0x2663},
2606     {0x2665, 0x2666},
2607     {0x2668, 0x2668},
2608     {0x267b, 0x267b},
2609     {0x267f, 0x267f},
2610     {0x2692, 0x2694},
2611     {0x2696, 0x2697},
2612     {0x2699, 0x2699},
2613     {0x269b, 0x269c},
2614     {0x26a0, 0x26a1},
2615     {0x26aa, 0x26ab},
2616     {0x26b0, 0x26b1},
2617     {0x26bd, 0x26be},
2618     {0x26c4, 0x26c5},
2619     {0x26c8, 0x26c8},
2620     {0x26ce, 0x26cf},
2621     {0x26d1, 0x26d1},
2622     {0x26d3, 0x26d4},
2623     {0x26e9, 0x26ea},
2624     {0x26f0, 0x26f5},
2625     {0x26f7, 0x26fa},
2626     {0x26fd, 0x26fd},
2627     {0x2702, 0x2702},
2628     {0x2705, 0x2705},
2629     {0x2708, 0x270d},
2630     {0x270f, 0x270f},
2631     {0x2712, 0x2712},
2632     {0x2714, 0x2714},
2633     {0x2716, 0x2716},
2634     {0x271d, 0x271d},
2635     {0x2721, 0x2721},
2636     {0x2728, 0x2728},
2637     {0x2733, 0x2734},
2638     {0x2744, 0x2744},
2639     {0x2747, 0x2747},
2640     {0x274c, 0x274c},
2641     {0x274e, 0x274e},
2642     {0x2753, 0x2755},
2643     {0x2757, 0x2757},
2644     {0x2763, 0x2764},
2645     {0x2795, 0x2797},
2646     {0x27a1, 0x27a1},
2647     {0x27b0, 0x27b0},
2648     {0x27bf, 0x27bf},
2649     {0x2934, 0x2935},
2650     {0x2b05, 0x2b07},
2651     {0x2b1b, 0x2b1c},
2652     {0x2b50, 0x2b50},
2653     {0x2b55, 0x2b55},
2654     {0x3030, 0x3030},
2655     {0x303d, 0x303d},
2656     {0x3297, 0x3297},
2657     {0x3299, 0x3299},
2658     {0x1f004, 0x1f004},
2659     {0x1f0cf, 0x1f0cf},
2660     {0x1f170, 0x1f171},
2661     {0x1f17e, 0x1f17f},
2662     {0x1f18e, 0x1f18e},
2663     {0x1f191, 0x1f19a},
2664     {0x1f1e6, 0x1f1ff},
2665     {0x1f201, 0x1f202},
2666     {0x1f21a, 0x1f21a},
2667     {0x1f22f, 0x1f22f},
2668     {0x1f232, 0x1f23a},
2669     {0x1f250, 0x1f251},
2670     {0x1f300, 0x1f320},
2671     {0x1f330, 0x1f335},
2672     {0x1f337, 0x1f37c},
2673     {0x1f380, 0x1f393},
2674     {0x1f3a0, 0x1f3c4},
2675     {0x1f3c6, 0x1f3ca},
2676     {0x1f3e0, 0x1f3f0},
2677     {0x1f400, 0x1f43e},
2678     {0x1f440, 0x1f440},
2679     {0x1f442, 0x1f4f7},
2680     {0x1f4f9, 0x1f4fc},
2681     {0x1f500, 0x1f53d},
2682     {0x1f550, 0x1f567},
2683     {0x1f5fb, 0x1f640},
2684     {0x1f645, 0x1f64f},
2685     {0x1f680, 0x1f6c5}
2686 };
2687 
2688 /*
2689  * Get class of a Unicode character.
2690  * 0: white space
2691  * 1: punctuation
2692  * 2 or bigger: some class of word character.
2693  */
2694     int
2695 utf_class(int c)
2696 {
2697     /* sorted list of non-overlapping intervals */
2698     static struct clinterval
2699     {
2700 	unsigned int first;
2701 	unsigned int last;
2702 	unsigned int class;
2703     } classes[] =
2704     {
2705 	{0x037e, 0x037e, 1},		/* Greek question mark */
2706 	{0x0387, 0x0387, 1},		/* Greek ano teleia */
2707 	{0x055a, 0x055f, 1},		/* Armenian punctuation */
2708 	{0x0589, 0x0589, 1},		/* Armenian full stop */
2709 	{0x05be, 0x05be, 1},
2710 	{0x05c0, 0x05c0, 1},
2711 	{0x05c3, 0x05c3, 1},
2712 	{0x05f3, 0x05f4, 1},
2713 	{0x060c, 0x060c, 1},
2714 	{0x061b, 0x061b, 1},
2715 	{0x061f, 0x061f, 1},
2716 	{0x066a, 0x066d, 1},
2717 	{0x06d4, 0x06d4, 1},
2718 	{0x0700, 0x070d, 1},		/* Syriac punctuation */
2719 	{0x0964, 0x0965, 1},
2720 	{0x0970, 0x0970, 1},
2721 	{0x0df4, 0x0df4, 1},
2722 	{0x0e4f, 0x0e4f, 1},
2723 	{0x0e5a, 0x0e5b, 1},
2724 	{0x0f04, 0x0f12, 1},
2725 	{0x0f3a, 0x0f3d, 1},
2726 	{0x0f85, 0x0f85, 1},
2727 	{0x104a, 0x104f, 1},		/* Myanmar punctuation */
2728 	{0x10fb, 0x10fb, 1},		/* Georgian punctuation */
2729 	{0x1361, 0x1368, 1},		/* Ethiopic punctuation */
2730 	{0x166d, 0x166e, 1},		/* Canadian Syl. punctuation */
2731 	{0x1680, 0x1680, 0},
2732 	{0x169b, 0x169c, 1},
2733 	{0x16eb, 0x16ed, 1},
2734 	{0x1735, 0x1736, 1},
2735 	{0x17d4, 0x17dc, 1},		/* Khmer punctuation */
2736 	{0x1800, 0x180a, 1},		/* Mongolian punctuation */
2737 	{0x2000, 0x200b, 0},		/* spaces */
2738 	{0x200c, 0x2027, 1},		/* punctuation and symbols */
2739 	{0x2028, 0x2029, 0},
2740 	{0x202a, 0x202e, 1},		/* punctuation and symbols */
2741 	{0x202f, 0x202f, 0},
2742 	{0x2030, 0x205e, 1},		/* punctuation and symbols */
2743 	{0x205f, 0x205f, 0},
2744 	{0x2060, 0x27ff, 1},		/* punctuation and symbols */
2745 	{0x2070, 0x207f, 0x2070},	/* superscript */
2746 	{0x2080, 0x2094, 0x2080},	/* subscript */
2747 	{0x20a0, 0x27ff, 1},		/* all kinds of symbols */
2748 	{0x2800, 0x28ff, 0x2800},	/* braille */
2749 	{0x2900, 0x2998, 1},		/* arrows, brackets, etc. */
2750 	{0x29d8, 0x29db, 1},
2751 	{0x29fc, 0x29fd, 1},
2752 	{0x2e00, 0x2e7f, 1},		/* supplemental punctuation */
2753 	{0x3000, 0x3000, 0},		/* ideographic space */
2754 	{0x3001, 0x3020, 1},		/* ideographic punctuation */
2755 	{0x3030, 0x3030, 1},
2756 	{0x303d, 0x303d, 1},
2757 	{0x3040, 0x309f, 0x3040},	/* Hiragana */
2758 	{0x30a0, 0x30ff, 0x30a0},	/* Katakana */
2759 	{0x3300, 0x9fff, 0x4e00},	/* CJK Ideographs */
2760 	{0xac00, 0xd7a3, 0xac00},	/* Hangul Syllables */
2761 	{0xf900, 0xfaff, 0x4e00},	/* CJK Ideographs */
2762 	{0xfd3e, 0xfd3f, 1},
2763 	{0xfe30, 0xfe6b, 1},		/* punctuation forms */
2764 	{0xff00, 0xff0f, 1},		/* half/fullwidth ASCII */
2765 	{0xff1a, 0xff20, 1},		/* half/fullwidth ASCII */
2766 	{0xff3b, 0xff40, 1},		/* half/fullwidth ASCII */
2767 	{0xff5b, 0xff65, 1},		/* half/fullwidth ASCII */
2768 	{0x20000, 0x2a6df, 0x4e00},	/* CJK Ideographs */
2769 	{0x2a700, 0x2b73f, 0x4e00},	/* CJK Ideographs */
2770 	{0x2b740, 0x2b81f, 0x4e00},	/* CJK Ideographs */
2771 	{0x2f800, 0x2fa1f, 0x4e00},	/* CJK Ideographs */
2772     };
2773 
2774     int bot = 0;
2775     int top = sizeof(classes) / sizeof(struct clinterval) - 1;
2776     int mid;
2777 
2778     /* First quick check for Latin1 characters, use 'iskeyword'. */
2779     if (c < 0x100)
2780     {
2781 	if (c == ' ' || c == '\t' || c == NUL || c == 0xa0)
2782 	    return 0;	    /* blank */
2783 	if (vim_iswordc(c))
2784 	    return 2;	    /* word character */
2785 	return 1;	    /* punctuation */
2786     }
2787 
2788     /* binary search in table */
2789     while (top >= bot)
2790     {
2791 	mid = (bot + top) / 2;
2792 	if (classes[mid].last < (unsigned int)c)
2793 	    bot = mid + 1;
2794 	else if (classes[mid].first > (unsigned int)c)
2795 	    top = mid - 1;
2796 	else
2797 	    return (int)classes[mid].class;
2798     }
2799 
2800     /* emoji */
2801     if (intable(emoji_all, sizeof(emoji_all), c))
2802 	return 3;
2803 
2804     /* most other characters are "word" characters */
2805     return 2;
2806 }
2807 
2808     int
2809 utf_ambiguous_width(int c)
2810 {
2811     return c >= 0x80 && (intable(ambiguous, sizeof(ambiguous), c)
2812 	    || intable(emoji_all, sizeof(emoji_all), c));
2813 }
2814 
2815 /*
2816  * Code for Unicode case-dependent operations.  Based on notes in
2817  * http://www.unicode.org/Public/UNIDATA/CaseFolding.txt
2818  * This code uses simple case folding, not full case folding.
2819  * Last updated for Unicode 5.2.
2820  */
2821 
2822 /*
2823  * The following tables are built by ../runtime/tools/unicode.vim.
2824  * They must be in numeric order, because we use binary search.
2825  * An entry such as {0x41,0x5a,1,32} means that Unicode characters in the
2826  * range from 0x41 to 0x5a inclusive, stepping by 1, are changed to
2827  * folded/upper/lower by adding 32.
2828  */
2829 typedef struct
2830 {
2831     int rangeStart;
2832     int rangeEnd;
2833     int step;
2834     int offset;
2835 } convertStruct;
2836 
2837 static convertStruct foldCase[] =
2838 {
2839 	{0x41,0x5a,1,32},
2840 	{0xb5,0xb5,-1,775},
2841 	{0xc0,0xd6,1,32},
2842 	{0xd8,0xde,1,32},
2843 	{0x100,0x12e,2,1},
2844 	{0x132,0x136,2,1},
2845 	{0x139,0x147,2,1},
2846 	{0x14a,0x176,2,1},
2847 	{0x178,0x178,-1,-121},
2848 	{0x179,0x17d,2,1},
2849 	{0x17f,0x17f,-1,-268},
2850 	{0x181,0x181,-1,210},
2851 	{0x182,0x184,2,1},
2852 	{0x186,0x186,-1,206},
2853 	{0x187,0x187,-1,1},
2854 	{0x189,0x18a,1,205},
2855 	{0x18b,0x18b,-1,1},
2856 	{0x18e,0x18e,-1,79},
2857 	{0x18f,0x18f,-1,202},
2858 	{0x190,0x190,-1,203},
2859 	{0x191,0x191,-1,1},
2860 	{0x193,0x193,-1,205},
2861 	{0x194,0x194,-1,207},
2862 	{0x196,0x196,-1,211},
2863 	{0x197,0x197,-1,209},
2864 	{0x198,0x198,-1,1},
2865 	{0x19c,0x19c,-1,211},
2866 	{0x19d,0x19d,-1,213},
2867 	{0x19f,0x19f,-1,214},
2868 	{0x1a0,0x1a4,2,1},
2869 	{0x1a6,0x1a6,-1,218},
2870 	{0x1a7,0x1a7,-1,1},
2871 	{0x1a9,0x1a9,-1,218},
2872 	{0x1ac,0x1ac,-1,1},
2873 	{0x1ae,0x1ae,-1,218},
2874 	{0x1af,0x1af,-1,1},
2875 	{0x1b1,0x1b2,1,217},
2876 	{0x1b3,0x1b5,2,1},
2877 	{0x1b7,0x1b7,-1,219},
2878 	{0x1b8,0x1bc,4,1},
2879 	{0x1c4,0x1c4,-1,2},
2880 	{0x1c5,0x1c5,-1,1},
2881 	{0x1c7,0x1c7,-1,2},
2882 	{0x1c8,0x1c8,-1,1},
2883 	{0x1ca,0x1ca,-1,2},
2884 	{0x1cb,0x1db,2,1},
2885 	{0x1de,0x1ee,2,1},
2886 	{0x1f1,0x1f1,-1,2},
2887 	{0x1f2,0x1f4,2,1},
2888 	{0x1f6,0x1f6,-1,-97},
2889 	{0x1f7,0x1f7,-1,-56},
2890 	{0x1f8,0x21e,2,1},
2891 	{0x220,0x220,-1,-130},
2892 	{0x222,0x232,2,1},
2893 	{0x23a,0x23a,-1,10795},
2894 	{0x23b,0x23b,-1,1},
2895 	{0x23d,0x23d,-1,-163},
2896 	{0x23e,0x23e,-1,10792},
2897 	{0x241,0x241,-1,1},
2898 	{0x243,0x243,-1,-195},
2899 	{0x244,0x244,-1,69},
2900 	{0x245,0x245,-1,71},
2901 	{0x246,0x24e,2,1},
2902 	{0x345,0x345,-1,116},
2903 	{0x370,0x372,2,1},
2904 	{0x376,0x376,-1,1},
2905 	{0x37f,0x37f,-1,116},
2906 	{0x386,0x386,-1,38},
2907 	{0x388,0x38a,1,37},
2908 	{0x38c,0x38c,-1,64},
2909 	{0x38e,0x38f,1,63},
2910 	{0x391,0x3a1,1,32},
2911 	{0x3a3,0x3ab,1,32},
2912 	{0x3c2,0x3c2,-1,1},
2913 	{0x3cf,0x3cf,-1,8},
2914 	{0x3d0,0x3d0,-1,-30},
2915 	{0x3d1,0x3d1,-1,-25},
2916 	{0x3d5,0x3d5,-1,-15},
2917 	{0x3d6,0x3d6,-1,-22},
2918 	{0x3d8,0x3ee,2,1},
2919 	{0x3f0,0x3f0,-1,-54},
2920 	{0x3f1,0x3f1,-1,-48},
2921 	{0x3f4,0x3f4,-1,-60},
2922 	{0x3f5,0x3f5,-1,-64},
2923 	{0x3f7,0x3f7,-1,1},
2924 	{0x3f9,0x3f9,-1,-7},
2925 	{0x3fa,0x3fa,-1,1},
2926 	{0x3fd,0x3ff,1,-130},
2927 	{0x400,0x40f,1,80},
2928 	{0x410,0x42f,1,32},
2929 	{0x460,0x480,2,1},
2930 	{0x48a,0x4be,2,1},
2931 	{0x4c0,0x4c0,-1,15},
2932 	{0x4c1,0x4cd,2,1},
2933 	{0x4d0,0x52e,2,1},
2934 	{0x531,0x556,1,48},
2935 	{0x10a0,0x10c5,1,7264},
2936 	{0x10c7,0x10cd,6,7264},
2937 	{0x13f8,0x13fd,1,-8},
2938 	{0x1c80,0x1c80,-1,-6222},
2939 	{0x1c81,0x1c81,-1,-6221},
2940 	{0x1c82,0x1c82,-1,-6212},
2941 	{0x1c83,0x1c84,1,-6210},
2942 	{0x1c85,0x1c85,-1,-6211},
2943 	{0x1c86,0x1c86,-1,-6204},
2944 	{0x1c87,0x1c87,-1,-6180},
2945 	{0x1c88,0x1c88,-1,35267},
2946 	{0x1e00,0x1e94,2,1},
2947 	{0x1e9b,0x1e9b,-1,-58},
2948 	{0x1e9e,0x1e9e,-1,-7615},
2949 	{0x1ea0,0x1efe,2,1},
2950 	{0x1f08,0x1f0f,1,-8},
2951 	{0x1f18,0x1f1d,1,-8},
2952 	{0x1f28,0x1f2f,1,-8},
2953 	{0x1f38,0x1f3f,1,-8},
2954 	{0x1f48,0x1f4d,1,-8},
2955 	{0x1f59,0x1f5f,2,-8},
2956 	{0x1f68,0x1f6f,1,-8},
2957 	{0x1f88,0x1f8f,1,-8},
2958 	{0x1f98,0x1f9f,1,-8},
2959 	{0x1fa8,0x1faf,1,-8},
2960 	{0x1fb8,0x1fb9,1,-8},
2961 	{0x1fba,0x1fbb,1,-74},
2962 	{0x1fbc,0x1fbc,-1,-9},
2963 	{0x1fbe,0x1fbe,-1,-7173},
2964 	{0x1fc8,0x1fcb,1,-86},
2965 	{0x1fcc,0x1fcc,-1,-9},
2966 	{0x1fd8,0x1fd9,1,-8},
2967 	{0x1fda,0x1fdb,1,-100},
2968 	{0x1fe8,0x1fe9,1,-8},
2969 	{0x1fea,0x1feb,1,-112},
2970 	{0x1fec,0x1fec,-1,-7},
2971 	{0x1ff8,0x1ff9,1,-128},
2972 	{0x1ffa,0x1ffb,1,-126},
2973 	{0x1ffc,0x1ffc,-1,-9},
2974 	{0x2126,0x2126,-1,-7517},
2975 	{0x212a,0x212a,-1,-8383},
2976 	{0x212b,0x212b,-1,-8262},
2977 	{0x2132,0x2132,-1,28},
2978 	{0x2160,0x216f,1,16},
2979 	{0x2183,0x2183,-1,1},
2980 	{0x24b6,0x24cf,1,26},
2981 	{0x2c00,0x2c2e,1,48},
2982 	{0x2c60,0x2c60,-1,1},
2983 	{0x2c62,0x2c62,-1,-10743},
2984 	{0x2c63,0x2c63,-1,-3814},
2985 	{0x2c64,0x2c64,-1,-10727},
2986 	{0x2c67,0x2c6b,2,1},
2987 	{0x2c6d,0x2c6d,-1,-10780},
2988 	{0x2c6e,0x2c6e,-1,-10749},
2989 	{0x2c6f,0x2c6f,-1,-10783},
2990 	{0x2c70,0x2c70,-1,-10782},
2991 	{0x2c72,0x2c75,3,1},
2992 	{0x2c7e,0x2c7f,1,-10815},
2993 	{0x2c80,0x2ce2,2,1},
2994 	{0x2ceb,0x2ced,2,1},
2995 	{0x2cf2,0xa640,31054,1},
2996 	{0xa642,0xa66c,2,1},
2997 	{0xa680,0xa69a,2,1},
2998 	{0xa722,0xa72e,2,1},
2999 	{0xa732,0xa76e,2,1},
3000 	{0xa779,0xa77b,2,1},
3001 	{0xa77d,0xa77d,-1,-35332},
3002 	{0xa77e,0xa786,2,1},
3003 	{0xa78b,0xa78b,-1,1},
3004 	{0xa78d,0xa78d,-1,-42280},
3005 	{0xa790,0xa792,2,1},
3006 	{0xa796,0xa7a8,2,1},
3007 	{0xa7aa,0xa7aa,-1,-42308},
3008 	{0xa7ab,0xa7ab,-1,-42319},
3009 	{0xa7ac,0xa7ac,-1,-42315},
3010 	{0xa7ad,0xa7ad,-1,-42305},
3011 	{0xa7ae,0xa7ae,-1,-42308},
3012 	{0xa7b0,0xa7b0,-1,-42258},
3013 	{0xa7b1,0xa7b1,-1,-42282},
3014 	{0xa7b2,0xa7b2,-1,-42261},
3015 	{0xa7b3,0xa7b3,-1,928},
3016 	{0xa7b4,0xa7b6,2,1},
3017 	{0xab70,0xabbf,1,-38864},
3018 	{0xff21,0xff3a,1,32},
3019 	{0x10400,0x10427,1,40},
3020 	{0x104b0,0x104d3,1,40},
3021 	{0x10c80,0x10cb2,1,64},
3022 	{0x118a0,0x118bf,1,32},
3023 	{0x1e900,0x1e921,1,34}
3024 };
3025 
3026 static int utf_convert(int a, convertStruct table[], int tableSize);
3027 static int utf_strnicmp(char_u *s1, char_u *s2, size_t n1, size_t n2);
3028 
3029 /*
3030  * Generic conversion function for case operations.
3031  * Return the converted equivalent of "a", which is a UCS-4 character.  Use
3032  * the given conversion "table".  Uses binary search on "table".
3033  */
3034     static int
3035 utf_convert(
3036     int			a,
3037     convertStruct	table[],
3038     int			tableSize)
3039 {
3040     int start, mid, end; /* indices into table */
3041     int entries = tableSize / sizeof(convertStruct);
3042 
3043     start = 0;
3044     end = entries;
3045     while (start < end)
3046     {
3047 	/* need to search further */
3048 	mid = (end + start) / 2;
3049 	if (table[mid].rangeEnd < a)
3050 	    start = mid + 1;
3051 	else
3052 	    end = mid;
3053     }
3054     if (start < entries
3055 	    && table[start].rangeStart <= a
3056 	    && a <= table[start].rangeEnd
3057 	    && (a - table[start].rangeStart) % table[start].step == 0)
3058 	return (a + table[start].offset);
3059     else
3060 	return a;
3061 }
3062 
3063 /*
3064  * Return the folded-case equivalent of "a", which is a UCS-4 character.  Uses
3065  * simple case folding.
3066  */
3067     int
3068 utf_fold(int a)
3069 {
3070     if (a < 0x80)
3071 	/* be fast for ASCII */
3072 	return a >= 0x41 && a <= 0x5a ? a + 32 : a;
3073     return utf_convert(a, foldCase, (int)sizeof(foldCase));
3074 }
3075 
3076 static convertStruct toLower[] =
3077 {
3078 	{0x41,0x5a,1,32},
3079 	{0xc0,0xd6,1,32},
3080 	{0xd8,0xde,1,32},
3081 	{0x100,0x12e,2,1},
3082 	{0x130,0x130,-1,-199},
3083 	{0x132,0x136,2,1},
3084 	{0x139,0x147,2,1},
3085 	{0x14a,0x176,2,1},
3086 	{0x178,0x178,-1,-121},
3087 	{0x179,0x17d,2,1},
3088 	{0x181,0x181,-1,210},
3089 	{0x182,0x184,2,1},
3090 	{0x186,0x186,-1,206},
3091 	{0x187,0x187,-1,1},
3092 	{0x189,0x18a,1,205},
3093 	{0x18b,0x18b,-1,1},
3094 	{0x18e,0x18e,-1,79},
3095 	{0x18f,0x18f,-1,202},
3096 	{0x190,0x190,-1,203},
3097 	{0x191,0x191,-1,1},
3098 	{0x193,0x193,-1,205},
3099 	{0x194,0x194,-1,207},
3100 	{0x196,0x196,-1,211},
3101 	{0x197,0x197,-1,209},
3102 	{0x198,0x198,-1,1},
3103 	{0x19c,0x19c,-1,211},
3104 	{0x19d,0x19d,-1,213},
3105 	{0x19f,0x19f,-1,214},
3106 	{0x1a0,0x1a4,2,1},
3107 	{0x1a6,0x1a6,-1,218},
3108 	{0x1a7,0x1a7,-1,1},
3109 	{0x1a9,0x1a9,-1,218},
3110 	{0x1ac,0x1ac,-1,1},
3111 	{0x1ae,0x1ae,-1,218},
3112 	{0x1af,0x1af,-1,1},
3113 	{0x1b1,0x1b2,1,217},
3114 	{0x1b3,0x1b5,2,1},
3115 	{0x1b7,0x1b7,-1,219},
3116 	{0x1b8,0x1bc,4,1},
3117 	{0x1c4,0x1c4,-1,2},
3118 	{0x1c5,0x1c5,-1,1},
3119 	{0x1c7,0x1c7,-1,2},
3120 	{0x1c8,0x1c8,-1,1},
3121 	{0x1ca,0x1ca,-1,2},
3122 	{0x1cb,0x1db,2,1},
3123 	{0x1de,0x1ee,2,1},
3124 	{0x1f1,0x1f1,-1,2},
3125 	{0x1f2,0x1f4,2,1},
3126 	{0x1f6,0x1f6,-1,-97},
3127 	{0x1f7,0x1f7,-1,-56},
3128 	{0x1f8,0x21e,2,1},
3129 	{0x220,0x220,-1,-130},
3130 	{0x222,0x232,2,1},
3131 	{0x23a,0x23a,-1,10795},
3132 	{0x23b,0x23b,-1,1},
3133 	{0x23d,0x23d,-1,-163},
3134 	{0x23e,0x23e,-1,10792},
3135 	{0x241,0x241,-1,1},
3136 	{0x243,0x243,-1,-195},
3137 	{0x244,0x244,-1,69},
3138 	{0x245,0x245,-1,71},
3139 	{0x246,0x24e,2,1},
3140 	{0x370,0x372,2,1},
3141 	{0x376,0x376,-1,1},
3142 	{0x37f,0x37f,-1,116},
3143 	{0x386,0x386,-1,38},
3144 	{0x388,0x38a,1,37},
3145 	{0x38c,0x38c,-1,64},
3146 	{0x38e,0x38f,1,63},
3147 	{0x391,0x3a1,1,32},
3148 	{0x3a3,0x3ab,1,32},
3149 	{0x3cf,0x3cf,-1,8},
3150 	{0x3d8,0x3ee,2,1},
3151 	{0x3f4,0x3f4,-1,-60},
3152 	{0x3f7,0x3f7,-1,1},
3153 	{0x3f9,0x3f9,-1,-7},
3154 	{0x3fa,0x3fa,-1,1},
3155 	{0x3fd,0x3ff,1,-130},
3156 	{0x400,0x40f,1,80},
3157 	{0x410,0x42f,1,32},
3158 	{0x460,0x480,2,1},
3159 	{0x48a,0x4be,2,1},
3160 	{0x4c0,0x4c0,-1,15},
3161 	{0x4c1,0x4cd,2,1},
3162 	{0x4d0,0x52e,2,1},
3163 	{0x531,0x556,1,48},
3164 	{0x10a0,0x10c5,1,7264},
3165 	{0x10c7,0x10cd,6,7264},
3166 	{0x13a0,0x13ef,1,38864},
3167 	{0x13f0,0x13f5,1,8},
3168 	{0x1e00,0x1e94,2,1},
3169 	{0x1e9e,0x1e9e,-1,-7615},
3170 	{0x1ea0,0x1efe,2,1},
3171 	{0x1f08,0x1f0f,1,-8},
3172 	{0x1f18,0x1f1d,1,-8},
3173 	{0x1f28,0x1f2f,1,-8},
3174 	{0x1f38,0x1f3f,1,-8},
3175 	{0x1f48,0x1f4d,1,-8},
3176 	{0x1f59,0x1f5f,2,-8},
3177 	{0x1f68,0x1f6f,1,-8},
3178 	{0x1f88,0x1f8f,1,-8},
3179 	{0x1f98,0x1f9f,1,-8},
3180 	{0x1fa8,0x1faf,1,-8},
3181 	{0x1fb8,0x1fb9,1,-8},
3182 	{0x1fba,0x1fbb,1,-74},
3183 	{0x1fbc,0x1fbc,-1,-9},
3184 	{0x1fc8,0x1fcb,1,-86},
3185 	{0x1fcc,0x1fcc,-1,-9},
3186 	{0x1fd8,0x1fd9,1,-8},
3187 	{0x1fda,0x1fdb,1,-100},
3188 	{0x1fe8,0x1fe9,1,-8},
3189 	{0x1fea,0x1feb,1,-112},
3190 	{0x1fec,0x1fec,-1,-7},
3191 	{0x1ff8,0x1ff9,1,-128},
3192 	{0x1ffa,0x1ffb,1,-126},
3193 	{0x1ffc,0x1ffc,-1,-9},
3194 	{0x2126,0x2126,-1,-7517},
3195 	{0x212a,0x212a,-1,-8383},
3196 	{0x212b,0x212b,-1,-8262},
3197 	{0x2132,0x2132,-1,28},
3198 	{0x2160,0x216f,1,16},
3199 	{0x2183,0x2183,-1,1},
3200 	{0x24b6,0x24cf,1,26},
3201 	{0x2c00,0x2c2e,1,48},
3202 	{0x2c60,0x2c60,-1,1},
3203 	{0x2c62,0x2c62,-1,-10743},
3204 	{0x2c63,0x2c63,-1,-3814},
3205 	{0x2c64,0x2c64,-1,-10727},
3206 	{0x2c67,0x2c6b,2,1},
3207 	{0x2c6d,0x2c6d,-1,-10780},
3208 	{0x2c6e,0x2c6e,-1,-10749},
3209 	{0x2c6f,0x2c6f,-1,-10783},
3210 	{0x2c70,0x2c70,-1,-10782},
3211 	{0x2c72,0x2c75,3,1},
3212 	{0x2c7e,0x2c7f,1,-10815},
3213 	{0x2c80,0x2ce2,2,1},
3214 	{0x2ceb,0x2ced,2,1},
3215 	{0x2cf2,0xa640,31054,1},
3216 	{0xa642,0xa66c,2,1},
3217 	{0xa680,0xa69a,2,1},
3218 	{0xa722,0xa72e,2,1},
3219 	{0xa732,0xa76e,2,1},
3220 	{0xa779,0xa77b,2,1},
3221 	{0xa77d,0xa77d,-1,-35332},
3222 	{0xa77e,0xa786,2,1},
3223 	{0xa78b,0xa78b,-1,1},
3224 	{0xa78d,0xa78d,-1,-42280},
3225 	{0xa790,0xa792,2,1},
3226 	{0xa796,0xa7a8,2,1},
3227 	{0xa7aa,0xa7aa,-1,-42308},
3228 	{0xa7ab,0xa7ab,-1,-42319},
3229 	{0xa7ac,0xa7ac,-1,-42315},
3230 	{0xa7ad,0xa7ad,-1,-42305},
3231 	{0xa7ae,0xa7ae,-1,-42308},
3232 	{0xa7b0,0xa7b0,-1,-42258},
3233 	{0xa7b1,0xa7b1,-1,-42282},
3234 	{0xa7b2,0xa7b2,-1,-42261},
3235 	{0xa7b3,0xa7b3,-1,928},
3236 	{0xa7b4,0xa7b6,2,1},
3237 	{0xff21,0xff3a,1,32},
3238 	{0x10400,0x10427,1,40},
3239 	{0x104b0,0x104d3,1,40},
3240 	{0x10c80,0x10cb2,1,64},
3241 	{0x118a0,0x118bf,1,32},
3242 	{0x1e900,0x1e921,1,34}
3243 };
3244 
3245 static convertStruct toUpper[] =
3246 {
3247 	{0x61,0x7a,1,-32},
3248 	{0xb5,0xb5,-1,743},
3249 	{0xe0,0xf6,1,-32},
3250 	{0xf8,0xfe,1,-32},
3251 	{0xff,0xff,-1,121},
3252 	{0x101,0x12f,2,-1},
3253 	{0x131,0x131,-1,-232},
3254 	{0x133,0x137,2,-1},
3255 	{0x13a,0x148,2,-1},
3256 	{0x14b,0x177,2,-1},
3257 	{0x17a,0x17e,2,-1},
3258 	{0x17f,0x17f,-1,-300},
3259 	{0x180,0x180,-1,195},
3260 	{0x183,0x185,2,-1},
3261 	{0x188,0x18c,4,-1},
3262 	{0x192,0x192,-1,-1},
3263 	{0x195,0x195,-1,97},
3264 	{0x199,0x199,-1,-1},
3265 	{0x19a,0x19a,-1,163},
3266 	{0x19e,0x19e,-1,130},
3267 	{0x1a1,0x1a5,2,-1},
3268 	{0x1a8,0x1ad,5,-1},
3269 	{0x1b0,0x1b4,4,-1},
3270 	{0x1b6,0x1b9,3,-1},
3271 	{0x1bd,0x1bd,-1,-1},
3272 	{0x1bf,0x1bf,-1,56},
3273 	{0x1c5,0x1c5,-1,-1},
3274 	{0x1c6,0x1c6,-1,-2},
3275 	{0x1c8,0x1c8,-1,-1},
3276 	{0x1c9,0x1c9,-1,-2},
3277 	{0x1cb,0x1cb,-1,-1},
3278 	{0x1cc,0x1cc,-1,-2},
3279 	{0x1ce,0x1dc,2,-1},
3280 	{0x1dd,0x1dd,-1,-79},
3281 	{0x1df,0x1ef,2,-1},
3282 	{0x1f2,0x1f2,-1,-1},
3283 	{0x1f3,0x1f3,-1,-2},
3284 	{0x1f5,0x1f9,4,-1},
3285 	{0x1fb,0x21f,2,-1},
3286 	{0x223,0x233,2,-1},
3287 	{0x23c,0x23c,-1,-1},
3288 	{0x23f,0x240,1,10815},
3289 	{0x242,0x247,5,-1},
3290 	{0x249,0x24f,2,-1},
3291 	{0x250,0x250,-1,10783},
3292 	{0x251,0x251,-1,10780},
3293 	{0x252,0x252,-1,10782},
3294 	{0x253,0x253,-1,-210},
3295 	{0x254,0x254,-1,-206},
3296 	{0x256,0x257,1,-205},
3297 	{0x259,0x259,-1,-202},
3298 	{0x25b,0x25b,-1,-203},
3299 	{0x25c,0x25c,-1,42319},
3300 	{0x260,0x260,-1,-205},
3301 	{0x261,0x261,-1,42315},
3302 	{0x263,0x263,-1,-207},
3303 	{0x265,0x265,-1,42280},
3304 	{0x266,0x266,-1,42308},
3305 	{0x268,0x268,-1,-209},
3306 	{0x269,0x269,-1,-211},
3307 	{0x26a,0x26a,-1,42308},
3308 	{0x26b,0x26b,-1,10743},
3309 	{0x26c,0x26c,-1,42305},
3310 	{0x26f,0x26f,-1,-211},
3311 	{0x271,0x271,-1,10749},
3312 	{0x272,0x272,-1,-213},
3313 	{0x275,0x275,-1,-214},
3314 	{0x27d,0x27d,-1,10727},
3315 	{0x280,0x283,3,-218},
3316 	{0x287,0x287,-1,42282},
3317 	{0x288,0x288,-1,-218},
3318 	{0x289,0x289,-1,-69},
3319 	{0x28a,0x28b,1,-217},
3320 	{0x28c,0x28c,-1,-71},
3321 	{0x292,0x292,-1,-219},
3322 	{0x29d,0x29d,-1,42261},
3323 	{0x29e,0x29e,-1,42258},
3324 	{0x345,0x345,-1,84},
3325 	{0x371,0x373,2,-1},
3326 	{0x377,0x377,-1,-1},
3327 	{0x37b,0x37d,1,130},
3328 	{0x3ac,0x3ac,-1,-38},
3329 	{0x3ad,0x3af,1,-37},
3330 	{0x3b1,0x3c1,1,-32},
3331 	{0x3c2,0x3c2,-1,-31},
3332 	{0x3c3,0x3cb,1,-32},
3333 	{0x3cc,0x3cc,-1,-64},
3334 	{0x3cd,0x3ce,1,-63},
3335 	{0x3d0,0x3d0,-1,-62},
3336 	{0x3d1,0x3d1,-1,-57},
3337 	{0x3d5,0x3d5,-1,-47},
3338 	{0x3d6,0x3d6,-1,-54},
3339 	{0x3d7,0x3d7,-1,-8},
3340 	{0x3d9,0x3ef,2,-1},
3341 	{0x3f0,0x3f0,-1,-86},
3342 	{0x3f1,0x3f1,-1,-80},
3343 	{0x3f2,0x3f2,-1,7},
3344 	{0x3f3,0x3f3,-1,-116},
3345 	{0x3f5,0x3f5,-1,-96},
3346 	{0x3f8,0x3fb,3,-1},
3347 	{0x430,0x44f,1,-32},
3348 	{0x450,0x45f,1,-80},
3349 	{0x461,0x481,2,-1},
3350 	{0x48b,0x4bf,2,-1},
3351 	{0x4c2,0x4ce,2,-1},
3352 	{0x4cf,0x4cf,-1,-15},
3353 	{0x4d1,0x52f,2,-1},
3354 	{0x561,0x586,1,-48},
3355 	{0x13f8,0x13fd,1,-8},
3356 	{0x1c80,0x1c80,-1,-6254},
3357 	{0x1c81,0x1c81,-1,-6253},
3358 	{0x1c82,0x1c82,-1,-6244},
3359 	{0x1c83,0x1c84,1,-6242},
3360 	{0x1c85,0x1c85,-1,-6243},
3361 	{0x1c86,0x1c86,-1,-6236},
3362 	{0x1c87,0x1c87,-1,-6181},
3363 	{0x1c88,0x1c88,-1,35266},
3364 	{0x1d79,0x1d79,-1,35332},
3365 	{0x1d7d,0x1d7d,-1,3814},
3366 	{0x1e01,0x1e95,2,-1},
3367 	{0x1e9b,0x1e9b,-1,-59},
3368 	{0x1ea1,0x1eff,2,-1},
3369 	{0x1f00,0x1f07,1,8},
3370 	{0x1f10,0x1f15,1,8},
3371 	{0x1f20,0x1f27,1,8},
3372 	{0x1f30,0x1f37,1,8},
3373 	{0x1f40,0x1f45,1,8},
3374 	{0x1f51,0x1f57,2,8},
3375 	{0x1f60,0x1f67,1,8},
3376 	{0x1f70,0x1f71,1,74},
3377 	{0x1f72,0x1f75,1,86},
3378 	{0x1f76,0x1f77,1,100},
3379 	{0x1f78,0x1f79,1,128},
3380 	{0x1f7a,0x1f7b,1,112},
3381 	{0x1f7c,0x1f7d,1,126},
3382 	{0x1f80,0x1f87,1,8},
3383 	{0x1f90,0x1f97,1,8},
3384 	{0x1fa0,0x1fa7,1,8},
3385 	{0x1fb0,0x1fb1,1,8},
3386 	{0x1fb3,0x1fb3,-1,9},
3387 	{0x1fbe,0x1fbe,-1,-7205},
3388 	{0x1fc3,0x1fc3,-1,9},
3389 	{0x1fd0,0x1fd1,1,8},
3390 	{0x1fe0,0x1fe1,1,8},
3391 	{0x1fe5,0x1fe5,-1,7},
3392 	{0x1ff3,0x1ff3,-1,9},
3393 	{0x214e,0x214e,-1,-28},
3394 	{0x2170,0x217f,1,-16},
3395 	{0x2184,0x2184,-1,-1},
3396 	{0x24d0,0x24e9,1,-26},
3397 	{0x2c30,0x2c5e,1,-48},
3398 	{0x2c61,0x2c61,-1,-1},
3399 	{0x2c65,0x2c65,-1,-10795},
3400 	{0x2c66,0x2c66,-1,-10792},
3401 	{0x2c68,0x2c6c,2,-1},
3402 	{0x2c73,0x2c76,3,-1},
3403 	{0x2c81,0x2ce3,2,-1},
3404 	{0x2cec,0x2cee,2,-1},
3405 	{0x2cf3,0x2cf3,-1,-1},
3406 	{0x2d00,0x2d25,1,-7264},
3407 	{0x2d27,0x2d2d,6,-7264},
3408 	{0xa641,0xa66d,2,-1},
3409 	{0xa681,0xa69b,2,-1},
3410 	{0xa723,0xa72f,2,-1},
3411 	{0xa733,0xa76f,2,-1},
3412 	{0xa77a,0xa77c,2,-1},
3413 	{0xa77f,0xa787,2,-1},
3414 	{0xa78c,0xa791,5,-1},
3415 	{0xa793,0xa797,4,-1},
3416 	{0xa799,0xa7a9,2,-1},
3417 	{0xa7b5,0xa7b7,2,-1},
3418 	{0xab53,0xab53,-1,-928},
3419 	{0xab70,0xabbf,1,-38864},
3420 	{0xff41,0xff5a,1,-32},
3421 	{0x10428,0x1044f,1,-40},
3422 	{0x104d8,0x104fb,1,-40},
3423 	{0x10cc0,0x10cf2,1,-64},
3424 	{0x118c0,0x118df,1,-32},
3425 	{0x1e922,0x1e943,1,-34}
3426 };
3427 
3428 /*
3429  * Return the upper-case equivalent of "a", which is a UCS-4 character.  Use
3430  * simple case folding.
3431  */
3432     int
3433 utf_toupper(int a)
3434 {
3435     /* If 'casemap' contains "keepascii" use ASCII style toupper(). */
3436     if (a < 128 && (cmp_flags & CMP_KEEPASCII))
3437 	return TOUPPER_ASC(a);
3438 
3439 #if defined(HAVE_TOWUPPER) && defined(__STDC_ISO_10646__)
3440     /* If towupper() is available and handles Unicode, use it. */
3441     if (!(cmp_flags & CMP_INTERNAL))
3442 	return towupper(a);
3443 #endif
3444 
3445     /* For characters below 128 use locale sensitive toupper(). */
3446     if (a < 128)
3447 	return TOUPPER_LOC(a);
3448 
3449     /* For any other characters use the above mapping table. */
3450     return utf_convert(a, toUpper, (int)sizeof(toUpper));
3451 }
3452 
3453     int
3454 utf_islower(int a)
3455 {
3456     /* German sharp s is lower case but has no upper case equivalent. */
3457     return (utf_toupper(a) != a) || a == 0xdf;
3458 }
3459 
3460 /*
3461  * Return the lower-case equivalent of "a", which is a UCS-4 character.  Use
3462  * simple case folding.
3463  */
3464     int
3465 utf_tolower(int a)
3466 {
3467     /* If 'casemap' contains "keepascii" use ASCII style tolower(). */
3468     if (a < 128 && (cmp_flags & CMP_KEEPASCII))
3469 	return TOLOWER_ASC(a);
3470 
3471 #if defined(HAVE_TOWLOWER) && defined(__STDC_ISO_10646__)
3472     /* If towlower() is available and handles Unicode, use it. */
3473     if (!(cmp_flags & CMP_INTERNAL))
3474 	return towlower(a);
3475 #endif
3476 
3477     /* For characters below 128 use locale sensitive tolower(). */
3478     if (a < 128)
3479 	return TOLOWER_LOC(a);
3480 
3481     /* For any other characters use the above mapping table. */
3482     return utf_convert(a, toLower, (int)sizeof(toLower));
3483 }
3484 
3485     int
3486 utf_isupper(int a)
3487 {
3488     return (utf_tolower(a) != a);
3489 }
3490 
3491     static int
3492 utf_strnicmp(
3493     char_u      *s1,
3494     char_u      *s2,
3495     size_t      n1,
3496     size_t      n2)
3497 {
3498     int		c1, c2, cdiff;
3499     char_u	buffer[6];
3500 
3501     for (;;)
3502     {
3503 	c1 = utf_safe_read_char_adv(&s1, &n1);
3504 	c2 = utf_safe_read_char_adv(&s2, &n2);
3505 
3506 	if (c1 <= 0 || c2 <= 0)
3507 	    break;
3508 
3509 	if (c1 == c2)
3510 	    continue;
3511 
3512 	cdiff = utf_fold(c1) - utf_fold(c2);
3513 	if (cdiff != 0)
3514 	    return cdiff;
3515     }
3516 
3517     /* some string ended or has an incomplete/illegal character sequence */
3518 
3519     if (c1 == 0 || c2 == 0)
3520     {
3521 	/* some string ended. shorter string is smaller */
3522 	if (c1 == 0 && c2 == 0)
3523 	    return 0;
3524 	return c1 == 0 ? -1 : 1;
3525     }
3526 
3527     /* Continue with bytewise comparison to produce some result that
3528      * would make comparison operations involving this function transitive.
3529      *
3530      * If only one string had an error, comparison should be made with
3531      * folded version of the other string. In this case it is enough
3532      * to fold just one character to determine the result of comparison. */
3533 
3534     if (c1 != -1 && c2 == -1)
3535     {
3536 	n1 = utf_char2bytes(utf_fold(c1), buffer);
3537 	s1 = buffer;
3538     }
3539     else if (c2 != -1 && c1 == -1)
3540     {
3541 	n2 = utf_char2bytes(utf_fold(c2), buffer);
3542 	s2 = buffer;
3543     }
3544 
3545     while (n1 > 0 && n2 > 0 && *s1 != NUL && *s2 != NUL)
3546     {
3547 	cdiff = (int)(*s1) - (int)(*s2);
3548 	if (cdiff != 0)
3549 	    return cdiff;
3550 
3551 	s1++;
3552 	s2++;
3553 	n1--;
3554 	n2--;
3555     }
3556 
3557     if (n1 > 0 && *s1 == NUL)
3558 	n1 = 0;
3559     if (n2 > 0 && *s2 == NUL)
3560 	n2 = 0;
3561 
3562     if (n1 == 0 && n2 == 0)
3563 	return 0;
3564     return n1 == 0 ? -1 : 1;
3565 }
3566 
3567 /*
3568  * Version of strnicmp() that handles multi-byte characters.
3569  * Needed for Big5, Shift-JIS and UTF-8 encoding.  Other DBCS encodings can
3570  * probably use strnicmp(), because there are no ASCII characters in the
3571  * second byte.
3572  * Returns zero if s1 and s2 are equal (ignoring case), the difference between
3573  * two characters otherwise.
3574  */
3575     int
3576 mb_strnicmp(char_u *s1, char_u *s2, size_t nn)
3577 {
3578     int		i, l;
3579     int		cdiff;
3580     int		n = (int)nn;
3581 
3582     if (enc_utf8)
3583     {
3584 	return utf_strnicmp(s1, s2, nn, nn);
3585     }
3586     else
3587     {
3588 	for (i = 0; i < n; i += l)
3589 	{
3590 	    if (s1[i] == NUL && s2[i] == NUL)	/* both strings end */
3591 		return 0;
3592 
3593 	    l = (*mb_ptr2len)(s1 + i);
3594 	    if (l <= 1)
3595 	    {
3596 		/* Single byte: first check normally, then with ignore case. */
3597 		if (s1[i] != s2[i])
3598 		{
3599 		    cdiff = MB_TOLOWER(s1[i]) - MB_TOLOWER(s2[i]);
3600 		    if (cdiff != 0)
3601 			return cdiff;
3602 		}
3603 	    }
3604 	    else
3605 	    {
3606 		/* For non-Unicode multi-byte don't ignore case. */
3607 		if (l > n - i)
3608 		    l = n - i;
3609 		cdiff = STRNCMP(s1 + i, s2 + i, l);
3610 		if (cdiff != 0)
3611 		    return cdiff;
3612 	    }
3613 	}
3614     }
3615     return 0;
3616 }
3617 
3618 /*
3619  * "g8": show bytes of the UTF-8 char under the cursor.  Doesn't matter what
3620  * 'encoding' has been set to.
3621  */
3622     void
3623 show_utf8(void)
3624 {
3625     int		len;
3626     int		rlen = 0;
3627     char_u	*line;
3628     int		clen;
3629     int		i;
3630 
3631     /* Get the byte length of the char under the cursor, including composing
3632      * characters. */
3633     line = ml_get_cursor();
3634     len = utfc_ptr2len(line);
3635     if (len == 0)
3636     {
3637 	MSG("NUL");
3638 	return;
3639     }
3640 
3641     clen = 0;
3642     for (i = 0; i < len; ++i)
3643     {
3644 	if (clen == 0)
3645 	{
3646 	    /* start of (composing) character, get its length */
3647 	    if (i > 0)
3648 	    {
3649 		STRCPY(IObuff + rlen, "+ ");
3650 		rlen += 2;
3651 	    }
3652 	    clen = utf_ptr2len(line + i);
3653 	}
3654 	sprintf((char *)IObuff + rlen, "%02x ",
3655 		(line[i] == NL) ? NUL : line[i]);  /* NUL is stored as NL */
3656 	--clen;
3657 	rlen += (int)STRLEN(IObuff + rlen);
3658 	if (rlen > IOSIZE - 20)
3659 	    break;
3660     }
3661 
3662     msg(IObuff);
3663 }
3664 
3665 /*
3666  * mb_head_off() function pointer.
3667  * Return offset from "p" to the first byte of the character it points into.
3668  * If "p" points to the NUL at the end of the string return 0.
3669  * Returns 0 when already at the first byte of a character.
3670  */
3671     int
3672 latin_head_off(char_u *base UNUSED, char_u *p UNUSED)
3673 {
3674     return 0;
3675 }
3676 
3677     int
3678 dbcs_head_off(char_u *base, char_u *p)
3679 {
3680     char_u	*q;
3681 
3682     /* It can't be a trailing byte when not using DBCS, at the start of the
3683      * string or the previous byte can't start a double-byte. */
3684     if (p <= base || MB_BYTE2LEN(p[-1]) == 1 || *p == NUL)
3685 	return 0;
3686 
3687     /* This is slow: need to start at the base and go forward until the
3688      * byte we are looking for.  Return 1 when we went past it, 0 otherwise. */
3689     q = base;
3690     while (q < p)
3691 	q += dbcs_ptr2len(q);
3692     return (q == p) ? 0 : 1;
3693 }
3694 
3695 /*
3696  * Special version of dbcs_head_off() that works for ScreenLines[], where
3697  * single-width DBCS_JPNU characters are stored separately.
3698  */
3699     int
3700 dbcs_screen_head_off(char_u *base, char_u *p)
3701 {
3702     char_u	*q;
3703 
3704     /* It can't be a trailing byte when not using DBCS, at the start of the
3705      * string or the previous byte can't start a double-byte.
3706      * For euc-jp an 0x8e byte in the previous cell always means we have a
3707      * lead byte in the current cell. */
3708     if (p <= base
3709 	    || (enc_dbcs == DBCS_JPNU && p[-1] == 0x8e)
3710 	    || MB_BYTE2LEN(p[-1]) == 1
3711 	    || *p == NUL)
3712 	return 0;
3713 
3714     /* This is slow: need to start at the base and go forward until the
3715      * byte we are looking for.  Return 1 when we went past it, 0 otherwise.
3716      * For DBCS_JPNU look out for 0x8e, which means the second byte is not
3717      * stored as the next byte. */
3718     q = base;
3719     while (q < p)
3720     {
3721 	if (enc_dbcs == DBCS_JPNU && *q == 0x8e)
3722 	    ++q;
3723 	else
3724 	    q += dbcs_ptr2len(q);
3725     }
3726     return (q == p) ? 0 : 1;
3727 }
3728 
3729     int
3730 utf_head_off(char_u *base, char_u *p)
3731 {
3732     char_u	*q;
3733     char_u	*s;
3734     int		c;
3735     int		len;
3736 #ifdef FEAT_ARABIC
3737     char_u	*j;
3738 #endif
3739 
3740     if (*p < 0x80)		/* be quick for ASCII */
3741 	return 0;
3742 
3743     /* Skip backwards over trailing bytes: 10xx.xxxx
3744      * Skip backwards again if on a composing char. */
3745     for (q = p; ; --q)
3746     {
3747 	/* Move s to the last byte of this char. */
3748 	for (s = q; (s[1] & 0xc0) == 0x80; ++s)
3749 	    ;
3750 	/* Move q to the first byte of this char. */
3751 	while (q > base && (*q & 0xc0) == 0x80)
3752 	    --q;
3753 	/* Check for illegal sequence. Do allow an illegal byte after where we
3754 	 * started. */
3755 	len = utf8len_tab[*q];
3756 	if (len != (int)(s - q + 1) && len != (int)(p - q + 1))
3757 	    return 0;
3758 
3759 	if (q <= base)
3760 	    break;
3761 
3762 	c = utf_ptr2char(q);
3763 	if (utf_iscomposing(c))
3764 	    continue;
3765 
3766 #ifdef FEAT_ARABIC
3767 	if (arabic_maycombine(c))
3768 	{
3769 	    /* Advance to get a sneak-peak at the next char */
3770 	    j = q;
3771 	    --j;
3772 	    /* Move j to the first byte of this char. */
3773 	    while (j > base && (*j & 0xc0) == 0x80)
3774 		--j;
3775 	    if (arabic_combine(utf_ptr2char(j), c))
3776 		continue;
3777 	}
3778 #endif
3779 	break;
3780     }
3781 
3782     return (int)(p - q);
3783 }
3784 
3785 /*
3786  * Copy a character from "*fp" to "*tp" and advance the pointers.
3787  */
3788     void
3789 mb_copy_char(char_u **fp, char_u **tp)
3790 {
3791     int	    l = (*mb_ptr2len)(*fp);
3792 
3793     mch_memmove(*tp, *fp, (size_t)l);
3794     *tp += l;
3795     *fp += l;
3796 }
3797 
3798 /*
3799  * Return the offset from "p" to the first byte of a character.  When "p" is
3800  * at the start of a character 0 is returned, otherwise the offset to the next
3801  * character.  Can start anywhere in a stream of bytes.
3802  */
3803     int
3804 mb_off_next(char_u *base, char_u *p)
3805 {
3806     int		i;
3807     int		j;
3808 
3809     if (enc_utf8)
3810     {
3811 	if (*p < 0x80)		/* be quick for ASCII */
3812 	    return 0;
3813 
3814 	/* Find the next character that isn't 10xx.xxxx */
3815 	for (i = 0; (p[i] & 0xc0) == 0x80; ++i)
3816 	    ;
3817 	if (i > 0)
3818 	{
3819 	    /* Check for illegal sequence. */
3820 	    for (j = 0; p - j > base; ++j)
3821 		if ((p[-j] & 0xc0) != 0x80)
3822 		    break;
3823 	    if (utf8len_tab[p[-j]] != i + j)
3824 		return 0;
3825 	}
3826 	return i;
3827     }
3828 
3829     /* Only need to check if we're on a trail byte, it doesn't matter if we
3830      * want the offset to the next or current character. */
3831     return (*mb_head_off)(base, p);
3832 }
3833 
3834 /*
3835  * Return the offset from "p" to the last byte of the character it points
3836  * into.  Can start anywhere in a stream of bytes.
3837  */
3838     int
3839 mb_tail_off(char_u *base, char_u *p)
3840 {
3841     int		i;
3842     int		j;
3843 
3844     if (*p == NUL)
3845 	return 0;
3846 
3847     if (enc_utf8)
3848     {
3849 	/* Find the last character that is 10xx.xxxx */
3850 	for (i = 0; (p[i + 1] & 0xc0) == 0x80; ++i)
3851 	    ;
3852 	/* Check for illegal sequence. */
3853 	for (j = 0; p - j > base; ++j)
3854 	    if ((p[-j] & 0xc0) != 0x80)
3855 		break;
3856 	if (utf8len_tab[p[-j]] != i + j + 1)
3857 	    return 0;
3858 	return i;
3859     }
3860 
3861     /* It can't be the first byte if a double-byte when not using DBCS, at the
3862      * end of the string or the byte can't start a double-byte. */
3863     if (enc_dbcs == 0 || p[1] == NUL || MB_BYTE2LEN(*p) == 1)
3864 	return 0;
3865 
3866     /* Return 1 when on the lead byte, 0 when on the tail byte. */
3867     return 1 - dbcs_head_off(base, p);
3868 }
3869 
3870 /*
3871  * Find the next illegal byte sequence.
3872  */
3873     void
3874 utf_find_illegal(void)
3875 {
3876     pos_T	pos = curwin->w_cursor;
3877     char_u	*p;
3878     int		len;
3879     vimconv_T	vimconv;
3880     char_u	*tofree = NULL;
3881 
3882     vimconv.vc_type = CONV_NONE;
3883     if (enc_utf8 && (enc_canon_props(curbuf->b_p_fenc) & ENC_8BIT))
3884     {
3885 	/* 'encoding' is "utf-8" but we are editing a 8-bit encoded file,
3886 	 * possibly a utf-8 file with illegal bytes.  Setup for conversion
3887 	 * from utf-8 to 'fileencoding'. */
3888 	convert_setup(&vimconv, p_enc, curbuf->b_p_fenc);
3889     }
3890 
3891 #ifdef FEAT_VIRTUALEDIT
3892     curwin->w_cursor.coladd = 0;
3893 #endif
3894     for (;;)
3895     {
3896 	p = ml_get_cursor();
3897 	if (vimconv.vc_type != CONV_NONE)
3898 	{
3899 	    vim_free(tofree);
3900 	    tofree = string_convert(&vimconv, p, NULL);
3901 	    if (tofree == NULL)
3902 		break;
3903 	    p = tofree;
3904 	}
3905 
3906 	while (*p != NUL)
3907 	{
3908 	    /* Illegal means that there are not enough trail bytes (checked by
3909 	     * utf_ptr2len()) or too many of them (overlong sequence). */
3910 	    len = utf_ptr2len(p);
3911 	    if (*p >= 0x80 && (len == 1
3912 				     || utf_char2len(utf_ptr2char(p)) != len))
3913 	    {
3914 		if (vimconv.vc_type == CONV_NONE)
3915 		    curwin->w_cursor.col += (colnr_T)(p - ml_get_cursor());
3916 		else
3917 		{
3918 		    int	    l;
3919 
3920 		    len = (int)(p - tofree);
3921 		    for (p = ml_get_cursor(); *p != NUL && len-- > 0; p += l)
3922 		    {
3923 			l = utf_ptr2len(p);
3924 			curwin->w_cursor.col += l;
3925 		    }
3926 		}
3927 		goto theend;
3928 	    }
3929 	    p += len;
3930 	}
3931 	if (curwin->w_cursor.lnum == curbuf->b_ml.ml_line_count)
3932 	    break;
3933 	++curwin->w_cursor.lnum;
3934 	curwin->w_cursor.col = 0;
3935     }
3936 
3937     /* didn't find it: don't move and beep */
3938     curwin->w_cursor = pos;
3939     beep_flush();
3940 
3941 theend:
3942     vim_free(tofree);
3943     convert_setup(&vimconv, NULL, NULL);
3944 }
3945 
3946 #if defined(FEAT_GUI_GTK) || defined(PROTO)
3947 /*
3948  * Return TRUE if string "s" is a valid utf-8 string.
3949  * When "end" is NULL stop at the first NUL.
3950  * When "end" is positive stop there.
3951  */
3952     int
3953 utf_valid_string(char_u *s, char_u *end)
3954 {
3955     int		l;
3956     char_u	*p = s;
3957 
3958     while (end == NULL ? *p != NUL : p < end)
3959     {
3960 	l = utf8len_tab_zero[*p];
3961 	if (l == 0)
3962 	    return FALSE;	/* invalid lead byte */
3963 	if (end != NULL && p + l > end)
3964 	    return FALSE;	/* incomplete byte sequence */
3965 	++p;
3966 	while (--l > 0)
3967 	    if ((*p++ & 0xc0) != 0x80)
3968 		return FALSE;	/* invalid trail byte */
3969     }
3970     return TRUE;
3971 }
3972 #endif
3973 
3974 #if defined(FEAT_GUI) || defined(PROTO)
3975 /*
3976  * Special version of mb_tail_off() for use in ScreenLines[].
3977  */
3978     int
3979 dbcs_screen_tail_off(char_u *base, char_u *p)
3980 {
3981     /* It can't be the first byte if a double-byte when not using DBCS, at the
3982      * end of the string or the byte can't start a double-byte.
3983      * For euc-jp an 0x8e byte always means we have a lead byte in the current
3984      * cell. */
3985     if (*p == NUL || p[1] == NUL
3986 	    || (enc_dbcs == DBCS_JPNU && *p == 0x8e)
3987 	    || MB_BYTE2LEN(*p) == 1)
3988 	return 0;
3989 
3990     /* Return 1 when on the lead byte, 0 when on the tail byte. */
3991     return 1 - dbcs_screen_head_off(base, p);
3992 }
3993 #endif
3994 
3995 /*
3996  * If the cursor moves on an trail byte, set the cursor on the lead byte.
3997  * Thus it moves left if necessary.
3998  * Return TRUE when the cursor was adjusted.
3999  */
4000     void
4001 mb_adjust_cursor(void)
4002 {
4003     mb_adjustpos(curbuf, &curwin->w_cursor);
4004 }
4005 
4006 /*
4007  * Adjust position "*lp" to point to the first byte of a multi-byte character.
4008  * If it points to a tail byte it's moved backwards to the head byte.
4009  */
4010     void
4011 mb_adjustpos(buf_T *buf, pos_T *lp)
4012 {
4013     char_u	*p;
4014 
4015     if (lp->col > 0
4016 #ifdef FEAT_VIRTUALEDIT
4017 	    || lp->coladd > 1
4018 #endif
4019 	    )
4020     {
4021 	p = ml_get_buf(buf, lp->lnum, FALSE);
4022 	lp->col -= (*mb_head_off)(p, p + lp->col);
4023 #ifdef FEAT_VIRTUALEDIT
4024 	/* Reset "coladd" when the cursor would be on the right half of a
4025 	 * double-wide character. */
4026 	if (lp->coladd == 1
4027 		&& p[lp->col] != TAB
4028 		&& vim_isprintc((*mb_ptr2char)(p + lp->col))
4029 		&& ptr2cells(p + lp->col) > 1)
4030 	    lp->coladd = 0;
4031 #endif
4032     }
4033 }
4034 
4035 /*
4036  * Return a pointer to the character before "*p", if there is one.
4037  */
4038     char_u *
4039 mb_prevptr(
4040     char_u *line,	/* start of the string */
4041     char_u *p)
4042 {
4043     if (p > line)
4044 	mb_ptr_back(line, p);
4045     return p;
4046 }
4047 
4048 /*
4049  * Return the character length of "str".  Each multi-byte character (with
4050  * following composing characters) counts as one.
4051  */
4052     int
4053 mb_charlen(char_u *str)
4054 {
4055     char_u	*p = str;
4056     int		count;
4057 
4058     if (p == NULL)
4059 	return 0;
4060 
4061     for (count = 0; *p != NUL; count++)
4062 	p += (*mb_ptr2len)(p);
4063 
4064     return count;
4065 }
4066 
4067 #if defined(FEAT_SPELL) || defined(PROTO)
4068 /*
4069  * Like mb_charlen() but for a string with specified length.
4070  */
4071     int
4072 mb_charlen_len(char_u *str, int len)
4073 {
4074     char_u	*p = str;
4075     int		count;
4076 
4077     for (count = 0; *p != NUL && p < str + len; count++)
4078 	p += (*mb_ptr2len)(p);
4079 
4080     return count;
4081 }
4082 #endif
4083 
4084 /*
4085  * Try to un-escape a multi-byte character.
4086  * Used for the "to" and "from" part of a mapping.
4087  * Return the un-escaped string if it is a multi-byte character, and advance
4088  * "pp" to just after the bytes that formed it.
4089  * Return NULL if no multi-byte char was found.
4090  */
4091     char_u *
4092 mb_unescape(char_u **pp)
4093 {
4094     static char_u	buf[6];
4095     int			n;
4096     int			m = 0;
4097     char_u		*str = *pp;
4098 
4099     /* Must translate K_SPECIAL KS_SPECIAL KE_FILLER to K_SPECIAL and CSI
4100      * KS_EXTRA KE_CSI to CSI.
4101      * Maximum length of a utf-8 character is 4 bytes. */
4102     for (n = 0; str[n] != NUL && m < 4; ++n)
4103     {
4104 	if (str[n] == K_SPECIAL
4105 		&& str[n + 1] == KS_SPECIAL
4106 		&& str[n + 2] == KE_FILLER)
4107 	{
4108 	    buf[m++] = K_SPECIAL;
4109 	    n += 2;
4110 	}
4111 	else if ((str[n] == K_SPECIAL
4112 # ifdef FEAT_GUI
4113 		    || str[n] == CSI
4114 # endif
4115 		 )
4116 		&& str[n + 1] == KS_EXTRA
4117 		&& str[n + 2] == (int)KE_CSI)
4118 	{
4119 	    buf[m++] = CSI;
4120 	    n += 2;
4121 	}
4122 	else if (str[n] == K_SPECIAL
4123 # ifdef FEAT_GUI
4124 		|| str[n] == CSI
4125 # endif
4126 		)
4127 	    break;		/* a special key can't be a multibyte char */
4128 	else
4129 	    buf[m++] = str[n];
4130 	buf[m] = NUL;
4131 
4132 	/* Return a multi-byte character if it's found.  An illegal sequence
4133 	 * will result in a 1 here. */
4134 	if ((*mb_ptr2len)(buf) > 1)
4135 	{
4136 	    *pp = str + n + 1;
4137 	    return buf;
4138 	}
4139 
4140 	/* Bail out quickly for ASCII. */
4141 	if (buf[0] < 128)
4142 	    break;
4143     }
4144     return NULL;
4145 }
4146 
4147 /*
4148  * Return TRUE if the character at "row"/"col" on the screen is the left side
4149  * of a double-width character.
4150  * Caller must make sure "row" and "col" are not invalid!
4151  */
4152     int
4153 mb_lefthalve(int row, int col)
4154 {
4155 #ifdef FEAT_HANGULIN
4156     if (composing_hangul)
4157 	return TRUE;
4158 #endif
4159     return (*mb_off2cells)(LineOffset[row] + col,
4160 					LineOffset[row] + screen_Columns) > 1;
4161 }
4162 
4163 /*
4164  * Correct a position on the screen, if it's the right half of a double-wide
4165  * char move it to the left half.  Returns the corrected column.
4166  */
4167     int
4168 mb_fix_col(int col, int row)
4169 {
4170     col = check_col(col);
4171     row = check_row(row);
4172     if (has_mbyte && ScreenLines != NULL && col > 0
4173 	    && ((enc_dbcs
4174 		    && ScreenLines[LineOffset[row] + col] != NUL
4175 		    && dbcs_screen_head_off(ScreenLines + LineOffset[row],
4176 					 ScreenLines + LineOffset[row] + col))
4177 		|| (enc_utf8 && ScreenLines[LineOffset[row] + col] == 0)))
4178 	return col - 1;
4179     return col;
4180 }
4181 #endif
4182 
4183 #if defined(FEAT_MBYTE) || defined(FEAT_POSTSCRIPT) || defined(PROTO)
4184 static int enc_alias_search(char_u *name);
4185 
4186 /*
4187  * Skip the Vim specific head of a 'encoding' name.
4188  */
4189     char_u *
4190 enc_skip(char_u *p)
4191 {
4192     if (STRNCMP(p, "2byte-", 6) == 0)
4193 	return p + 6;
4194     if (STRNCMP(p, "8bit-", 5) == 0)
4195 	return p + 5;
4196     return p;
4197 }
4198 
4199 /*
4200  * Find the canonical name for encoding "enc".
4201  * When the name isn't recognized, returns "enc" itself, but with all lower
4202  * case characters and '_' replaced with '-'.
4203  * Returns an allocated string.  NULL for out-of-memory.
4204  */
4205     char_u *
4206 enc_canonize(char_u *enc)
4207 {
4208     char_u	*r;
4209     char_u	*p, *s;
4210     int		i;
4211 
4212 # ifdef FEAT_MBYTE
4213     if (STRCMP(enc, "default") == 0)
4214     {
4215 	/* Use the default encoding as it's found by set_init_1(). */
4216 	r = get_encoding_default();
4217 	if (r == NULL)
4218 	    r = (char_u *)"latin1";
4219 	return vim_strsave(r);
4220     }
4221 # endif
4222 
4223     /* copy "enc" to allocated memory, with room for two '-' */
4224     r = alloc((unsigned)(STRLEN(enc) + 3));
4225     if (r != NULL)
4226     {
4227 	/* Make it all lower case and replace '_' with '-'. */
4228 	p = r;
4229 	for (s = enc; *s != NUL; ++s)
4230 	{
4231 	    if (*s == '_')
4232 		*p++ = '-';
4233 	    else
4234 		*p++ = TOLOWER_ASC(*s);
4235 	}
4236 	*p = NUL;
4237 
4238 	/* Skip "2byte-" and "8bit-". */
4239 	p = enc_skip(r);
4240 
4241 	/* Change "microsoft-cp" to "cp".  Used in some spell files. */
4242 	if (STRNCMP(p, "microsoft-cp", 12) == 0)
4243 	    STRMOVE(p, p + 10);
4244 
4245 	/* "iso8859" -> "iso-8859" */
4246 	if (STRNCMP(p, "iso8859", 7) == 0)
4247 	{
4248 	    STRMOVE(p + 4, p + 3);
4249 	    p[3] = '-';
4250 	}
4251 
4252 	/* "iso-8859n" -> "iso-8859-n" */
4253 	if (STRNCMP(p, "iso-8859", 8) == 0 && p[8] != '-')
4254 	{
4255 	    STRMOVE(p + 9, p + 8);
4256 	    p[8] = '-';
4257 	}
4258 
4259 	/* "latin-N" -> "latinN" */
4260 	if (STRNCMP(p, "latin-", 6) == 0)
4261 	    STRMOVE(p + 5, p + 6);
4262 
4263 	if (enc_canon_search(p) >= 0)
4264 	{
4265 	    /* canonical name can be used unmodified */
4266 	    if (p != r)
4267 		STRMOVE(r, p);
4268 	}
4269 	else if ((i = enc_alias_search(p)) >= 0)
4270 	{
4271 	    /* alias recognized, get canonical name */
4272 	    vim_free(r);
4273 	    r = vim_strsave((char_u *)enc_canon_table[i].name);
4274 	}
4275     }
4276     return r;
4277 }
4278 
4279 /*
4280  * Search for an encoding alias of "name".
4281  * Returns -1 when not found.
4282  */
4283     static int
4284 enc_alias_search(char_u *name)
4285 {
4286     int		i;
4287 
4288     for (i = 0; enc_alias_table[i].name != NULL; ++i)
4289 	if (STRCMP(name, enc_alias_table[i].name) == 0)
4290 	    return enc_alias_table[i].canon;
4291     return -1;
4292 }
4293 #endif
4294 
4295 #if defined(FEAT_MBYTE) || defined(PROTO)
4296 
4297 #ifdef HAVE_LANGINFO_H
4298 # include <langinfo.h>
4299 #endif
4300 
4301 /*
4302  * Get the canonicalized encoding of the current locale.
4303  * Returns an allocated string when successful, NULL when not.
4304  */
4305     char_u *
4306 enc_locale(void)
4307 {
4308 #ifndef WIN3264
4309     char	*s;
4310     char	*p;
4311     int		i;
4312 #endif
4313     char	buf[50];
4314 #ifdef WIN3264
4315     long	acp = GetACP();
4316 
4317     if (acp == 1200)
4318 	STRCPY(buf, "ucs-2le");
4319     else if (acp == 1252)	    /* cp1252 is used as latin1 */
4320 	STRCPY(buf, "latin1");
4321     else
4322 	sprintf(buf, "cp%ld", acp);
4323 #else
4324 # ifdef HAVE_NL_LANGINFO_CODESET
4325     if ((s = nl_langinfo(CODESET)) == NULL || *s == NUL)
4326 # endif
4327 #  if defined(HAVE_LOCALE_H) || defined(X_LOCALE)
4328 	if ((s = setlocale(LC_CTYPE, NULL)) == NULL || *s == NUL)
4329 #  endif
4330 	    if ((s = getenv("LC_ALL")) == NULL || *s == NUL)
4331 		if ((s = getenv("LC_CTYPE")) == NULL || *s == NUL)
4332 		    s = getenv("LANG");
4333 
4334     if (s == NULL || *s == NUL)
4335 	return FAIL;
4336 
4337     /* The most generic locale format is:
4338      * language[_territory][.codeset][@modifier][+special][,[sponsor][_revision]]
4339      * If there is a '.' remove the part before it.
4340      * if there is something after the codeset, remove it.
4341      * Make the name lowercase and replace '_' with '-'.
4342      * Exception: "ja_JP.EUC" == "euc-jp", "zh_CN.EUC" = "euc-cn",
4343      * "ko_KR.EUC" == "euc-kr"
4344      */
4345     if ((p = (char *)vim_strchr((char_u *)s, '.')) != NULL)
4346     {
4347 	if (p > s + 2 && STRNICMP(p + 1, "EUC", 3) == 0
4348 			&& !isalnum((int)p[4]) && p[4] != '-' && p[-3] == '_')
4349 	{
4350 	    /* copy "XY.EUC" to "euc-XY" to buf[10] */
4351 	    STRCPY(buf + 10, "euc-");
4352 	    buf[14] = p[-2];
4353 	    buf[15] = p[-1];
4354 	    buf[16] = 0;
4355 	    s = buf + 10;
4356 	}
4357 	else
4358 	    s = p + 1;
4359     }
4360     for (i = 0; i < (int)sizeof(buf) - 1 && s[i] != NUL; ++i)
4361     {
4362 	if (s[i] == '_' || s[i] == '-')
4363 	    buf[i] = '-';
4364 	else if (isalnum((int)s[i]))
4365 	    buf[i] = TOLOWER_ASC(s[i]);
4366 	else
4367 	    break;
4368     }
4369     buf[i] = NUL;
4370 #endif
4371 
4372     return enc_canonize((char_u *)buf);
4373 }
4374 
4375 #if defined(WIN3264) || defined(PROTO) || defined(FEAT_CYGWIN_WIN32_CLIPBOARD)
4376 /*
4377  * Convert an encoding name to an MS-Windows codepage.
4378  * Returns zero if no codepage can be figured out.
4379  */
4380     int
4381 encname2codepage(char_u *name)
4382 {
4383     int		cp;
4384     char_u	*p = name;
4385     int		idx;
4386 
4387     if (STRNCMP(p, "8bit-", 5) == 0)
4388 	p += 5;
4389     else if (STRNCMP(p_enc, "2byte-", 6) == 0)
4390 	p += 6;
4391 
4392     if (p[0] == 'c' && p[1] == 'p')
4393 	cp = atoi((char *)p + 2);
4394     else if ((idx = enc_canon_search(p)) >= 0)
4395 	cp = enc_canon_table[idx].codepage;
4396     else
4397 	return 0;
4398     if (IsValidCodePage(cp))
4399 	return cp;
4400     return 0;
4401 }
4402 #endif
4403 
4404 # if defined(USE_ICONV) || defined(PROTO)
4405 
4406 static char_u *iconv_string(vimconv_T *vcp, char_u *str, int slen, int *unconvlenp, int *resultlenp);
4407 
4408 /*
4409  * Call iconv_open() with a check if iconv() works properly (there are broken
4410  * versions).
4411  * Returns (void *)-1 if failed.
4412  * (should return iconv_t, but that causes problems with prototypes).
4413  */
4414     void *
4415 my_iconv_open(char_u *to, char_u *from)
4416 {
4417     iconv_t	fd;
4418 #define ICONV_TESTLEN 400
4419     char_u	tobuf[ICONV_TESTLEN];
4420     char	*p;
4421     size_t	tolen;
4422     static int	iconv_ok = -1;
4423 
4424     if (iconv_ok == FALSE)
4425 	return (void *)-1;	/* detected a broken iconv() previously */
4426 
4427 #ifdef DYNAMIC_ICONV
4428     /* Check if the iconv.dll can be found. */
4429     if (!iconv_enabled(TRUE))
4430 	return (void *)-1;
4431 #endif
4432 
4433     fd = iconv_open((char *)enc_skip(to), (char *)enc_skip(from));
4434 
4435     if (fd != (iconv_t)-1 && iconv_ok == -1)
4436     {
4437 	/*
4438 	 * Do a dummy iconv() call to check if it actually works.  There is a
4439 	 * version of iconv() on Linux that is broken.  We can't ignore it,
4440 	 * because it's wide-spread.  The symptoms are that after outputting
4441 	 * the initial shift state the "to" pointer is NULL and conversion
4442 	 * stops for no apparent reason after about 8160 characters.
4443 	 */
4444 	p = (char *)tobuf;
4445 	tolen = ICONV_TESTLEN;
4446 	(void)iconv(fd, NULL, NULL, &p, &tolen);
4447 	if (p == NULL)
4448 	{
4449 	    iconv_ok = FALSE;
4450 	    iconv_close(fd);
4451 	    fd = (iconv_t)-1;
4452 	}
4453 	else
4454 	    iconv_ok = TRUE;
4455     }
4456 
4457     return (void *)fd;
4458 }
4459 
4460 /*
4461  * Convert the string "str[slen]" with iconv().
4462  * If "unconvlenp" is not NULL handle the string ending in an incomplete
4463  * sequence and set "*unconvlenp" to the length of it.
4464  * Returns the converted string in allocated memory.  NULL for an error.
4465  * If resultlenp is not NULL, sets it to the result length in bytes.
4466  */
4467     static char_u *
4468 iconv_string(
4469     vimconv_T	*vcp,
4470     char_u	*str,
4471     int		slen,
4472     int		*unconvlenp,
4473     int		*resultlenp)
4474 {
4475     const char	*from;
4476     size_t	fromlen;
4477     char	*to;
4478     size_t	tolen;
4479     size_t	len = 0;
4480     size_t	done = 0;
4481     char_u	*result = NULL;
4482     char_u	*p;
4483     int		l;
4484 
4485     from = (char *)str;
4486     fromlen = slen;
4487     for (;;)
4488     {
4489 	if (len == 0 || ICONV_ERRNO == ICONV_E2BIG)
4490 	{
4491 	    /* Allocate enough room for most conversions.  When re-allocating
4492 	     * increase the buffer size. */
4493 	    len = len + fromlen * 2 + 40;
4494 	    p = alloc((unsigned)len);
4495 	    if (p != NULL && done > 0)
4496 		mch_memmove(p, result, done);
4497 	    vim_free(result);
4498 	    result = p;
4499 	    if (result == NULL)	/* out of memory */
4500 		break;
4501 	}
4502 
4503 	to = (char *)result + done;
4504 	tolen = len - done - 2;
4505 	/* Avoid a warning for systems with a wrong iconv() prototype by
4506 	 * casting the second argument to void *. */
4507 	if (iconv(vcp->vc_fd, (void *)&from, &fromlen, &to, &tolen)
4508 								!= (size_t)-1)
4509 	{
4510 	    /* Finished, append a NUL. */
4511 	    *to = NUL;
4512 	    break;
4513 	}
4514 
4515 	/* Check both ICONV_EINVAL and EINVAL, because the dynamically loaded
4516 	 * iconv library may use one of them. */
4517 	if (!vcp->vc_fail && unconvlenp != NULL
4518 		&& (ICONV_ERRNO == ICONV_EINVAL || ICONV_ERRNO == EINVAL))
4519 	{
4520 	    /* Handle an incomplete sequence at the end. */
4521 	    *to = NUL;
4522 	    *unconvlenp = (int)fromlen;
4523 	    break;
4524 	}
4525 
4526 	/* Check both ICONV_EILSEQ and EILSEQ, because the dynamically loaded
4527 	 * iconv library may use one of them. */
4528 	else if (!vcp->vc_fail
4529 		&& (ICONV_ERRNO == ICONV_EILSEQ || ICONV_ERRNO == EILSEQ
4530 		    || ICONV_ERRNO == ICONV_EINVAL || ICONV_ERRNO == EINVAL))
4531 	{
4532 	    /* Can't convert: insert a '?' and skip a character.  This assumes
4533 	     * conversion from 'encoding' to something else.  In other
4534 	     * situations we don't know what to skip anyway. */
4535 	    *to++ = '?';
4536 	    if ((*mb_ptr2cells)((char_u *)from) > 1)
4537 		*to++ = '?';
4538 	    if (enc_utf8)
4539 		l = utfc_ptr2len_len((char_u *)from, (int)fromlen);
4540 	    else
4541 	    {
4542 		l = (*mb_ptr2len)((char_u *)from);
4543 		if (l > (int)fromlen)
4544 		    l = (int)fromlen;
4545 	    }
4546 	    from += l;
4547 	    fromlen -= l;
4548 	}
4549 	else if (ICONV_ERRNO != ICONV_E2BIG)
4550 	{
4551 	    /* conversion failed */
4552 	    vim_free(result);
4553 	    result = NULL;
4554 	    break;
4555 	}
4556 	/* Not enough room or skipping illegal sequence. */
4557 	done = to - (char *)result;
4558     }
4559 
4560     if (resultlenp != NULL && result != NULL)
4561 	*resultlenp = (int)(to - (char *)result);
4562     return result;
4563 }
4564 
4565 #  if defined(DYNAMIC_ICONV) || defined(PROTO)
4566 /*
4567  * Dynamically load the "iconv.dll" on Win32.
4568  */
4569 
4570 #   ifndef DYNAMIC_ICONV	    /* must be generating prototypes */
4571 #    define HINSTANCE int
4572 #   endif
4573 static HINSTANCE hIconvDLL = 0;
4574 static HINSTANCE hMsvcrtDLL = 0;
4575 
4576 #   ifndef DYNAMIC_ICONV_DLL
4577 #    define DYNAMIC_ICONV_DLL "iconv.dll"
4578 #    define DYNAMIC_ICONV_DLL_ALT1 "libiconv.dll"
4579 #    define DYNAMIC_ICONV_DLL_ALT2 "libiconv2.dll"
4580 #    define DYNAMIC_ICONV_DLL_ALT3 "libiconv-2.dll"
4581 #   endif
4582 #   ifndef DYNAMIC_MSVCRT_DLL
4583 #    define DYNAMIC_MSVCRT_DLL "msvcrt.dll"
4584 #   endif
4585 
4586 /*
4587  * Get the address of 'funcname' which is imported by 'hInst' DLL.
4588  */
4589     static void *
4590 get_iconv_import_func(HINSTANCE hInst, const char *funcname)
4591 {
4592     PBYTE			pImage = (PBYTE)hInst;
4593     PIMAGE_DOS_HEADER		pDOS = (PIMAGE_DOS_HEADER)hInst;
4594     PIMAGE_NT_HEADERS		pPE;
4595     PIMAGE_IMPORT_DESCRIPTOR	pImpDesc;
4596     PIMAGE_THUNK_DATA		pIAT;	    /* Import Address Table */
4597     PIMAGE_THUNK_DATA		pINT;	    /* Import Name Table */
4598     PIMAGE_IMPORT_BY_NAME	pImpName;
4599 
4600     if (pDOS->e_magic != IMAGE_DOS_SIGNATURE)
4601 	return NULL;
4602     pPE = (PIMAGE_NT_HEADERS)(pImage + pDOS->e_lfanew);
4603     if (pPE->Signature != IMAGE_NT_SIGNATURE)
4604 	return NULL;
4605     pImpDesc = (PIMAGE_IMPORT_DESCRIPTOR)(pImage
4606 	    + pPE->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT]
4607 							    .VirtualAddress);
4608     for (; pImpDesc->FirstThunk; ++pImpDesc)
4609     {
4610 	if (!pImpDesc->OriginalFirstThunk)
4611 	    continue;
4612 	pIAT = (PIMAGE_THUNK_DATA)(pImage + pImpDesc->FirstThunk);
4613 	pINT = (PIMAGE_THUNK_DATA)(pImage + pImpDesc->OriginalFirstThunk);
4614 	for (; pIAT->u1.Function; ++pIAT, ++pINT)
4615 	{
4616 	    if (IMAGE_SNAP_BY_ORDINAL(pINT->u1.Ordinal))
4617 		continue;
4618 	    pImpName = (PIMAGE_IMPORT_BY_NAME)(pImage
4619 					+ (UINT_PTR)(pINT->u1.AddressOfData));
4620 	    if (strcmp((char *)pImpName->Name, funcname) == 0)
4621 		return (void *)pIAT->u1.Function;
4622 	}
4623     }
4624     return NULL;
4625 }
4626 
4627 /*
4628  * Try opening the iconv.dll and return TRUE if iconv() can be used.
4629  */
4630     int
4631 iconv_enabled(int verbose)
4632 {
4633     if (hIconvDLL != 0 && hMsvcrtDLL != 0)
4634 	return TRUE;
4635 
4636     /* The iconv DLL file goes under different names, try them all.
4637      * Do the "2" version first, it's newer. */
4638 #ifdef DYNAMIC_ICONV_DLL_ALT2
4639     if (hIconvDLL == 0)
4640 	hIconvDLL = vimLoadLib(DYNAMIC_ICONV_DLL_ALT2);
4641 #endif
4642 #ifdef DYNAMIC_ICONV_DLL_ALT3
4643     if (hIconvDLL == 0)
4644 	hIconvDLL = vimLoadLib(DYNAMIC_ICONV_DLL_ALT3);
4645 #endif
4646     if (hIconvDLL == 0)
4647 	hIconvDLL = vimLoadLib(DYNAMIC_ICONV_DLL);
4648 #ifdef DYNAMIC_ICONV_DLL_ALT1
4649     if (hIconvDLL == 0)
4650 	hIconvDLL = vimLoadLib(DYNAMIC_ICONV_DLL_ALT1);
4651 #endif
4652 
4653     if (hIconvDLL != 0)
4654 	hMsvcrtDLL = vimLoadLib(DYNAMIC_MSVCRT_DLL);
4655     if (hIconvDLL == 0 || hMsvcrtDLL == 0)
4656     {
4657 	/* Only give the message when 'verbose' is set, otherwise it might be
4658 	 * done whenever a conversion is attempted. */
4659 	if (verbose && p_verbose > 0)
4660 	{
4661 	    verbose_enter();
4662 	    EMSG2(_(e_loadlib),
4663 		    hIconvDLL == 0 ? DYNAMIC_ICONV_DLL : DYNAMIC_MSVCRT_DLL);
4664 	    verbose_leave();
4665 	}
4666 	iconv_end();
4667 	return FALSE;
4668     }
4669 
4670     iconv	= (void *)GetProcAddress(hIconvDLL, "libiconv");
4671     iconv_open	= (void *)GetProcAddress(hIconvDLL, "libiconv_open");
4672     iconv_close	= (void *)GetProcAddress(hIconvDLL, "libiconv_close");
4673     iconvctl	= (void *)GetProcAddress(hIconvDLL, "libiconvctl");
4674     iconv_errno	= get_iconv_import_func(hIconvDLL, "_errno");
4675     if (iconv_errno == NULL)
4676 	iconv_errno = (void *)GetProcAddress(hMsvcrtDLL, "_errno");
4677     if (iconv == NULL || iconv_open == NULL || iconv_close == NULL
4678 	    || iconvctl == NULL || iconv_errno == NULL)
4679     {
4680 	iconv_end();
4681 	if (verbose && p_verbose > 0)
4682 	{
4683 	    verbose_enter();
4684 	    EMSG2(_(e_loadfunc), "for libiconv");
4685 	    verbose_leave();
4686 	}
4687 	return FALSE;
4688     }
4689     return TRUE;
4690 }
4691 
4692     void
4693 iconv_end(void)
4694 {
4695     /* Don't use iconv() when inputting or outputting characters. */
4696     if (input_conv.vc_type == CONV_ICONV)
4697 	convert_setup(&input_conv, NULL, NULL);
4698     if (output_conv.vc_type == CONV_ICONV)
4699 	convert_setup(&output_conv, NULL, NULL);
4700 
4701     if (hIconvDLL != 0)
4702 	FreeLibrary(hIconvDLL);
4703     if (hMsvcrtDLL != 0)
4704 	FreeLibrary(hMsvcrtDLL);
4705     hIconvDLL = 0;
4706     hMsvcrtDLL = 0;
4707 }
4708 #  endif /* DYNAMIC_ICONV */
4709 # endif /* USE_ICONV */
4710 
4711 #endif /* FEAT_MBYTE */
4712 
4713 #if defined(FEAT_XIM) || defined(PROTO)
4714 
4715 # if defined(FEAT_GUI_GTK) || defined(PROTO)
4716 static int xim_has_preediting INIT(= FALSE);  /* IM current status */
4717 
4718 /*
4719  * Set preedit_start_col to the current cursor position.
4720  */
4721     static void
4722 init_preedit_start_col(void)
4723 {
4724     if (State & CMDLINE)
4725 	preedit_start_col = cmdline_getvcol_cursor();
4726     else if (curwin != NULL && curwin->w_buffer != NULL)
4727 	getvcol(curwin, &curwin->w_cursor, &preedit_start_col, NULL, NULL);
4728     /* Prevent that preediting marks the buffer as changed. */
4729     xim_changed_while_preediting = curbuf->b_changed;
4730 }
4731 
4732 static int im_is_active	       = FALSE;	/* IM is enabled for current mode    */
4733 static int preedit_is_active   = FALSE;
4734 static int im_preedit_cursor   = 0;	/* cursor offset in characters       */
4735 static int im_preedit_trailing = 0;	/* number of characters after cursor */
4736 
4737 static unsigned long im_commit_handler_id  = 0;
4738 static unsigned int  im_activatekey_keyval = GDK_VoidSymbol;
4739 static unsigned int  im_activatekey_state  = 0;
4740 
4741     void
4742 im_set_active(int active)
4743 {
4744     int was_active;
4745 
4746     was_active = !!im_get_status();
4747     im_is_active = (active && !p_imdisable);
4748 
4749     if (im_is_active != was_active)
4750 	xim_reset();
4751 }
4752 
4753     void
4754 xim_set_focus(int focus)
4755 {
4756     if (xic != NULL)
4757     {
4758 	if (focus)
4759 	    gtk_im_context_focus_in(xic);
4760 	else
4761 	    gtk_im_context_focus_out(xic);
4762     }
4763 }
4764 
4765     void
4766 im_set_position(int row, int col)
4767 {
4768     if (xic != NULL)
4769     {
4770 	GdkRectangle area;
4771 
4772 	area.x = FILL_X(col);
4773 	area.y = FILL_Y(row);
4774 	area.width  = gui.char_width * (mb_lefthalve(row, col) ? 2 : 1);
4775 	area.height = gui.char_height;
4776 
4777 	gtk_im_context_set_cursor_location(xic, &area);
4778     }
4779 }
4780 
4781 #  if 0 || defined(PROTO) /* apparently only used in gui_x11.c */
4782     void
4783 xim_set_preedit(void)
4784 {
4785     im_set_position(gui.row, gui.col);
4786 }
4787 #  endif
4788 
4789     static void
4790 im_add_to_input(char_u *str, int len)
4791 {
4792     /* Convert from 'termencoding' (always "utf-8") to 'encoding' */
4793     if (input_conv.vc_type != CONV_NONE)
4794     {
4795 	str = string_convert(&input_conv, str, &len);
4796 	g_return_if_fail(str != NULL);
4797     }
4798 
4799     add_to_input_buf_csi(str, len);
4800 
4801     if (input_conv.vc_type != CONV_NONE)
4802 	vim_free(str);
4803 
4804     if (p_mh) /* blank out the pointer if necessary */
4805 	gui_mch_mousehide(TRUE);
4806 }
4807 
4808     static void
4809 im_delete_preedit(void)
4810 {
4811     char_u bskey[]  = {CSI, 'k', 'b'};
4812     char_u delkey[] = {CSI, 'k', 'D'};
4813 
4814     if (State & NORMAL)
4815     {
4816 	im_preedit_cursor = 0;
4817 	return;
4818     }
4819     for (; im_preedit_cursor > 0; --im_preedit_cursor)
4820 	add_to_input_buf(bskey, (int)sizeof(bskey));
4821 
4822     for (; im_preedit_trailing > 0; --im_preedit_trailing)
4823 	add_to_input_buf(delkey, (int)sizeof(delkey));
4824 }
4825 
4826 /*
4827  * Move the cursor left by "num_move_back" characters.
4828  * Note that ins_left() checks im_is_preediting() to avoid breaking undo for
4829  * these K_LEFT keys.
4830  */
4831     static void
4832 im_correct_cursor(int num_move_back)
4833 {
4834     char_u backkey[] = {CSI, 'k', 'l'};
4835 
4836     if (State & NORMAL)
4837 	return;
4838 #  ifdef FEAT_RIGHTLEFT
4839     if ((State & CMDLINE) == 0 && curwin != NULL && curwin->w_p_rl)
4840 	backkey[2] = 'r';
4841 #  endif
4842     for (; num_move_back > 0; --num_move_back)
4843 	add_to_input_buf(backkey, (int)sizeof(backkey));
4844 }
4845 
4846 static int xim_expected_char = NUL;
4847 static int xim_ignored_char = FALSE;
4848 
4849 /*
4850  * Update the mode and cursor while in an IM callback.
4851  */
4852     static void
4853 im_show_info(void)
4854 {
4855     int	    old_vgetc_busy;
4856 
4857     old_vgetc_busy = vgetc_busy;
4858     vgetc_busy = TRUE;
4859     showmode();
4860     vgetc_busy = old_vgetc_busy;
4861     if ((State & NORMAL) || (State & INSERT))
4862 	setcursor();
4863     out_flush();
4864 }
4865 
4866 /*
4867  * Callback invoked when the user finished preediting.
4868  * Put the final string into the input buffer.
4869  */
4870     static void
4871 im_commit_cb(GtkIMContext *context UNUSED,
4872 	     const gchar *str,
4873 	     gpointer data UNUSED)
4874 {
4875     int		slen = (int)STRLEN(str);
4876     int		add_to_input = TRUE;
4877     int		clen;
4878     int		len = slen;
4879     int		commit_with_preedit = TRUE;
4880     char_u	*im_str;
4881 
4882 #ifdef XIM_DEBUG
4883     xim_log("im_commit_cb(): %s\n", str);
4884 #endif
4885 
4886     /* The imhangul module doesn't reset the preedit string before
4887      * committing.  Call im_delete_preedit() to work around that. */
4888     im_delete_preedit();
4889 
4890     /* Indicate that preediting has finished. */
4891     if (preedit_start_col == MAXCOL)
4892     {
4893 	init_preedit_start_col();
4894 	commit_with_preedit = FALSE;
4895     }
4896 
4897     /* The thing which setting "preedit_start_col" to MAXCOL means that
4898      * "preedit_start_col" will be set forcedly when calling
4899      * preedit_changed_cb() next time.
4900      * "preedit_start_col" should not reset with MAXCOL on this part. Vim
4901      * is simulating the preediting by using add_to_input_str(). when
4902      * preedit begin immediately before committed, the typebuf is not
4903      * flushed to screen, then it can't get correct "preedit_start_col".
4904      * Thus, it should calculate the cells by adding cells of the committed
4905      * string. */
4906     if (input_conv.vc_type != CONV_NONE)
4907     {
4908 	im_str = string_convert(&input_conv, (char_u *)str, &len);
4909 	g_return_if_fail(im_str != NULL);
4910     }
4911     else
4912 	im_str = (char_u *)str;
4913 
4914     clen = mb_string2cells(im_str, len);
4915 
4916     if (input_conv.vc_type != CONV_NONE)
4917 	vim_free(im_str);
4918     preedit_start_col += clen;
4919 
4920     /* Is this a single character that matches a keypad key that's just
4921      * been pressed?  If so, we don't want it to be entered as such - let
4922      * us carry on processing the raw keycode so that it may be used in
4923      * mappings as <kSomething>. */
4924     if (xim_expected_char != NUL)
4925     {
4926 	/* We're currently processing a keypad or other special key */
4927 	if (slen == 1 && str[0] == xim_expected_char)
4928 	{
4929 	    /* It's a match - don't do it here */
4930 	    xim_ignored_char = TRUE;
4931 	    add_to_input = FALSE;
4932 	}
4933 	else
4934 	{
4935 	    /* Not a match */
4936 	    xim_ignored_char = FALSE;
4937 	}
4938     }
4939 
4940     if (add_to_input)
4941 	im_add_to_input((char_u *)str, slen);
4942 
4943     /* Inserting chars while "im_is_active" is set does not cause a change of
4944      * buffer.  When the chars are committed the buffer must be marked as
4945      * changed. */
4946     if (!commit_with_preedit)
4947 	preedit_start_col = MAXCOL;
4948 
4949     /* This flag is used in changed() at next call. */
4950     xim_changed_while_preediting = TRUE;
4951 
4952     if (gtk_main_level() > 0)
4953 	gtk_main_quit();
4954 }
4955 
4956 /*
4957  * Callback invoked after start to the preedit.
4958  */
4959     static void
4960 im_preedit_start_cb(GtkIMContext *context UNUSED, gpointer data UNUSED)
4961 {
4962 #ifdef XIM_DEBUG
4963     xim_log("im_preedit_start_cb()\n");
4964 #endif
4965 
4966     im_is_active = TRUE;
4967     preedit_is_active = TRUE;
4968     gui_update_cursor(TRUE, FALSE);
4969     im_show_info();
4970 }
4971 
4972 /*
4973  * Callback invoked after end to the preedit.
4974  */
4975     static void
4976 im_preedit_end_cb(GtkIMContext *context UNUSED, gpointer data UNUSED)
4977 {
4978 #ifdef XIM_DEBUG
4979     xim_log("im_preedit_end_cb()\n");
4980 #endif
4981     im_delete_preedit();
4982 
4983     /* Indicate that preediting has finished */
4984     preedit_start_col = MAXCOL;
4985     xim_has_preediting = FALSE;
4986 
4987 #if 0
4988     /* Removal of this line suggested by Takuhiro Nishioka.  Fixes that IM was
4989      * switched off unintentionally.  We now use preedit_is_active (added by
4990      * SungHyun Nam). */
4991     im_is_active = FALSE;
4992 #endif
4993     preedit_is_active = FALSE;
4994     gui_update_cursor(TRUE, FALSE);
4995     im_show_info();
4996 }
4997 
4998 /*
4999  * Callback invoked after changes to the preedit string.  If the preedit
5000  * string was empty before, remember the preedit start column so we know
5001  * where to apply feedback attributes.  Delete the previous preedit string
5002  * if there was one, save the new preedit cursor offset, and put the new
5003  * string into the input buffer.
5004  *
5005  * TODO: The pragmatic "put into input buffer" approach used here has
5006  *       several fundamental problems:
5007  *
5008  * - The characters in the preedit string are subject to remapping.
5009  *   That's broken, only the finally committed string should be remapped.
5010  *
5011  * - There is a race condition involved:  The retrieved value for the
5012  *   current cursor position will be wrong if any unprocessed characters
5013  *   are still queued in the input buffer.
5014  *
5015  * - Due to the lack of synchronization between the file buffer in memory
5016  *   and any typed characters, it's practically impossible to implement the
5017  *   "retrieve_surrounding" and "delete_surrounding" signals reliably.  IM
5018  *   modules for languages such as Thai are likely to rely on this feature
5019  *   for proper operation.
5020  *
5021  * Conclusions:  I think support for preediting needs to be moved to the
5022  * core parts of Vim.  Ideally, until it has been committed, the preediting
5023  * string should only be displayed and not affect the buffer content at all.
5024  * The question how to deal with the synchronization issue still remains.
5025  * Circumventing the input buffer is probably not desirable.  Anyway, I think
5026  * implementing "retrieve_surrounding" is the only hard problem.
5027  *
5028  * One way to solve all of this in a clean manner would be to queue all key
5029  * press/release events "as is" in the input buffer, and apply the IM filtering
5030  * at the receiving end of the queue.  This, however, would have a rather large
5031  * impact on the code base.  If there is an easy way to force processing of all
5032  * remaining input from within the "retrieve_surrounding" signal handler, this
5033  * might not be necessary.  Gotta ask on vim-dev for opinions.
5034  */
5035     static void
5036 im_preedit_changed_cb(GtkIMContext *context, gpointer data UNUSED)
5037 {
5038     char    *preedit_string = NULL;
5039     int	    cursor_index    = 0;
5040     int	    num_move_back   = 0;
5041     char_u  *str;
5042     char_u  *p;
5043     int	    i;
5044 
5045     gtk_im_context_get_preedit_string(context,
5046 				      &preedit_string, NULL,
5047 				      &cursor_index);
5048 
5049 #ifdef XIM_DEBUG
5050     xim_log("im_preedit_changed_cb(): %s\n", preedit_string);
5051 #endif
5052 
5053     g_return_if_fail(preedit_string != NULL); /* just in case */
5054 
5055     /* If preedit_start_col is MAXCOL set it to the current cursor position. */
5056     if (preedit_start_col == MAXCOL && preedit_string[0] != '\0')
5057     {
5058 	xim_has_preediting = TRUE;
5059 
5060 	/* Urgh, this breaks if the input buffer isn't empty now */
5061 	init_preedit_start_col();
5062     }
5063     else if (cursor_index == 0 && preedit_string[0] == '\0')
5064     {
5065 	xim_has_preediting = FALSE;
5066 
5067 	/* If at the start position (after typing backspace)
5068 	 * preedit_start_col must be reset. */
5069 	preedit_start_col = MAXCOL;
5070     }
5071 
5072     im_delete_preedit();
5073 
5074     /*
5075      * Compute the end of the preediting area: "preedit_end_col".
5076      * According to the documentation of gtk_im_context_get_preedit_string(),
5077      * the cursor_pos output argument returns the offset in bytes.  This is
5078      * unfortunately not true -- real life shows the offset is in characters,
5079      * and the GTK+ source code agrees with me.  Will file a bug later.
5080      */
5081     if (preedit_start_col != MAXCOL)
5082 	preedit_end_col = preedit_start_col;
5083     str = (char_u *)preedit_string;
5084     for (p = str, i = 0; *p != NUL; p += utf_byte2len(*p), ++i)
5085     {
5086 	int is_composing;
5087 
5088 	is_composing = ((*p & 0x80) != 0 && utf_iscomposing(utf_ptr2char(p)));
5089 	/*
5090 	 * These offsets are used as counters when generating <BS> and <Del>
5091 	 * to delete the preedit string.  So don't count composing characters
5092 	 * unless 'delcombine' is enabled.
5093 	 */
5094 	if (!is_composing || p_deco)
5095 	{
5096 	    if (i < cursor_index)
5097 		++im_preedit_cursor;
5098 	    else
5099 		++im_preedit_trailing;
5100 	}
5101 	if (!is_composing && i >= cursor_index)
5102 	{
5103 	    /* This is essentially the same as im_preedit_trailing, except
5104 	     * composing characters are not counted even if p_deco is set. */
5105 	    ++num_move_back;
5106 	}
5107 	if (preedit_start_col != MAXCOL)
5108 	    preedit_end_col += utf_ptr2cells(p);
5109     }
5110 
5111     if (p > str)
5112     {
5113 	im_add_to_input(str, (int)(p - str));
5114 	im_correct_cursor(num_move_back);
5115     }
5116 
5117     g_free(preedit_string);
5118 
5119     if (gtk_main_level() > 0)
5120 	gtk_main_quit();
5121 }
5122 
5123 /*
5124  * Translate the Pango attributes at iter to Vim highlighting attributes.
5125  * Ignore attributes not supported by Vim highlighting.  This shouldn't have
5126  * too much impact -- right now we handle even more attributes than necessary
5127  * for the IM modules I tested with.
5128  */
5129     static int
5130 translate_pango_attributes(PangoAttrIterator *iter)
5131 {
5132     PangoAttribute  *attr;
5133     int		    char_attr = HL_NORMAL;
5134 
5135     attr = pango_attr_iterator_get(iter, PANGO_ATTR_UNDERLINE);
5136     if (attr != NULL && ((PangoAttrInt *)attr)->value
5137 						 != (int)PANGO_UNDERLINE_NONE)
5138 	char_attr |= HL_UNDERLINE;
5139 
5140     attr = pango_attr_iterator_get(iter, PANGO_ATTR_WEIGHT);
5141     if (attr != NULL && ((PangoAttrInt *)attr)->value >= (int)PANGO_WEIGHT_BOLD)
5142 	char_attr |= HL_BOLD;
5143 
5144     attr = pango_attr_iterator_get(iter, PANGO_ATTR_STYLE);
5145     if (attr != NULL && ((PangoAttrInt *)attr)->value
5146 						   != (int)PANGO_STYLE_NORMAL)
5147 	char_attr |= HL_ITALIC;
5148 
5149     attr = pango_attr_iterator_get(iter, PANGO_ATTR_BACKGROUND);
5150     if (attr != NULL)
5151     {
5152 	const PangoColor *color = &((PangoAttrColor *)attr)->color;
5153 
5154 	/* Assume inverse if black background is requested */
5155 	if ((color->red | color->green | color->blue) == 0)
5156 	    char_attr |= HL_INVERSE;
5157     }
5158 
5159     return char_attr;
5160 }
5161 
5162 /*
5163  * Retrieve the highlighting attributes at column col in the preedit string.
5164  * Return -1 if not in preediting mode or if col is out of range.
5165  */
5166     int
5167 im_get_feedback_attr(int col)
5168 {
5169     char	    *preedit_string = NULL;
5170     PangoAttrList   *attr_list	    = NULL;
5171     int		    char_attr	    = -1;
5172 
5173     if (xic == NULL)
5174 	return char_attr;
5175 
5176     gtk_im_context_get_preedit_string(xic, &preedit_string, &attr_list, NULL);
5177 
5178     if (preedit_string != NULL && attr_list != NULL)
5179     {
5180 	int idx;
5181 
5182 	/* Get the byte index as used by PangoAttrIterator */
5183 	for (idx = 0; col > 0 && preedit_string[idx] != '\0'; --col)
5184 	    idx += utfc_ptr2len((char_u *)preedit_string + idx);
5185 
5186 	if (preedit_string[idx] != '\0')
5187 	{
5188 	    PangoAttrIterator	*iter;
5189 	    int			start, end;
5190 
5191 	    char_attr = HL_NORMAL;
5192 	    iter = pango_attr_list_get_iterator(attr_list);
5193 
5194 	    /* Extract all relevant attributes from the list. */
5195 	    do
5196 	    {
5197 		pango_attr_iterator_range(iter, &start, &end);
5198 
5199 		if (idx >= start && idx < end)
5200 		    char_attr |= translate_pango_attributes(iter);
5201 	    }
5202 	    while (pango_attr_iterator_next(iter));
5203 
5204 	    pango_attr_iterator_destroy(iter);
5205 	}
5206     }
5207 
5208     if (attr_list != NULL)
5209 	pango_attr_list_unref(attr_list);
5210     g_free(preedit_string);
5211 
5212     return char_attr;
5213 }
5214 
5215     void
5216 xim_init(void)
5217 {
5218 #ifdef XIM_DEBUG
5219     xim_log("xim_init()\n");
5220 #endif
5221 
5222     g_return_if_fail(gui.drawarea != NULL);
5223 #if GTK_CHECK_VERSION(3,0,0)
5224     g_return_if_fail(gtk_widget_get_window(gui.drawarea) != NULL);
5225 #else
5226     g_return_if_fail(gui.drawarea->window != NULL);
5227 #endif
5228 
5229     xic = gtk_im_multicontext_new();
5230     g_object_ref(xic);
5231 
5232     im_commit_handler_id = g_signal_connect(G_OBJECT(xic), "commit",
5233 					    G_CALLBACK(&im_commit_cb), NULL);
5234     g_signal_connect(G_OBJECT(xic), "preedit_changed",
5235 		     G_CALLBACK(&im_preedit_changed_cb), NULL);
5236     g_signal_connect(G_OBJECT(xic), "preedit_start",
5237 		     G_CALLBACK(&im_preedit_start_cb), NULL);
5238     g_signal_connect(G_OBJECT(xic), "preedit_end",
5239 		     G_CALLBACK(&im_preedit_end_cb), NULL);
5240 
5241 #if GTK_CHECK_VERSION(3,0,0)
5242     gtk_im_context_set_client_window(xic, gtk_widget_get_window(gui.drawarea));
5243 #else
5244     gtk_im_context_set_client_window(xic, gui.drawarea->window);
5245 #endif
5246 }
5247 
5248     void
5249 im_shutdown(void)
5250 {
5251 #ifdef XIM_DEBUG
5252     xim_log("im_shutdown()\n");
5253 #endif
5254 
5255     if (xic != NULL)
5256     {
5257 	gtk_im_context_focus_out(xic);
5258 	g_object_unref(xic);
5259 	xic = NULL;
5260     }
5261     im_is_active = FALSE;
5262     im_commit_handler_id = 0;
5263     preedit_start_col = MAXCOL;
5264     xim_has_preediting = FALSE;
5265 }
5266 
5267 /*
5268  * Convert the string argument to keyval and state for GdkEventKey.
5269  * If str is valid return TRUE, otherwise FALSE.
5270  *
5271  * See 'imactivatekey' for documentation of the format.
5272  */
5273     static int
5274 im_string_to_keyval(const char *str, unsigned int *keyval, unsigned int *state)
5275 {
5276     const char	    *mods_end;
5277     unsigned	    tmp_keyval;
5278     unsigned	    tmp_state = 0;
5279 
5280     mods_end = strrchr(str, '-');
5281     mods_end = (mods_end != NULL) ? mods_end + 1 : str;
5282 
5283     /* Parse modifier keys */
5284     while (str < mods_end)
5285 	switch (*str++)
5286 	{
5287 	    case '-':							break;
5288 	    case 'S': case 's': tmp_state |= (unsigned)GDK_SHIFT_MASK;	break;
5289 	    case 'L': case 'l': tmp_state |= (unsigned)GDK_LOCK_MASK;	break;
5290 	    case 'C': case 'c': tmp_state |= (unsigned)GDK_CONTROL_MASK;break;
5291 	    case '1':		tmp_state |= (unsigned)GDK_MOD1_MASK;	break;
5292 	    case '2':		tmp_state |= (unsigned)GDK_MOD2_MASK;	break;
5293 	    case '3':		tmp_state |= (unsigned)GDK_MOD3_MASK;	break;
5294 	    case '4':		tmp_state |= (unsigned)GDK_MOD4_MASK;	break;
5295 	    case '5':		tmp_state |= (unsigned)GDK_MOD5_MASK;	break;
5296 	    default:
5297 		return FALSE;
5298 	}
5299 
5300     tmp_keyval = gdk_keyval_from_name(str);
5301 
5302     if (tmp_keyval == 0 || tmp_keyval == GDK_VoidSymbol)
5303 	return FALSE;
5304 
5305     if (keyval != NULL)
5306 	*keyval = tmp_keyval;
5307     if (state != NULL)
5308 	*state = tmp_state;
5309 
5310     return TRUE;
5311 }
5312 
5313 /*
5314  * Return TRUE if p_imak is valid, otherwise FALSE.  As a special case, an
5315  * empty string is also regarded as valid.
5316  *
5317  * Note: The numerical key value of p_imak is cached if it was valid; thus
5318  * boldly assuming im_xim_isvalid_imactivate() will always be called whenever
5319  * 'imak' changes.  This is currently the case but not obvious -- should
5320  * probably rename the function for clarity.
5321  */
5322     int
5323 im_xim_isvalid_imactivate(void)
5324 {
5325     if (p_imak[0] == NUL)
5326     {
5327 	im_activatekey_keyval = GDK_VoidSymbol;
5328 	im_activatekey_state  = 0;
5329 	return TRUE;
5330     }
5331 
5332     return im_string_to_keyval((const char *)p_imak,
5333 			       &im_activatekey_keyval,
5334 			       &im_activatekey_state);
5335 }
5336 
5337     static void
5338 im_synthesize_keypress(unsigned int keyval, unsigned int state)
5339 {
5340     GdkEventKey *event;
5341 
5342 #  ifdef HAVE_GTK_MULTIHEAD
5343     event = (GdkEventKey *)gdk_event_new(GDK_KEY_PRESS);
5344 #   if GTK_CHECK_VERSION(3,0,0)
5345     g_object_ref(gtk_widget_get_window(gui.drawarea));
5346 					/* unreffed by gdk_event_free() */
5347 #   else
5348     g_object_ref(gui.drawarea->window); /* unreffed by gdk_event_free() */
5349 #   endif
5350 #  else
5351     event = (GdkEventKey *)g_malloc0((gulong)sizeof(GdkEvent));
5352     event->type = GDK_KEY_PRESS;
5353 #  endif
5354 #  if GTK_CHECK_VERSION(3,0,0)
5355     event->window = gtk_widget_get_window(gui.drawarea);
5356 #  else
5357     event->window = gui.drawarea->window;
5358 #  endif
5359     event->send_event = TRUE;
5360     event->time = GDK_CURRENT_TIME;
5361     event->state  = state;
5362     event->keyval = keyval;
5363     event->hardware_keycode = /* needed for XIM */
5364 	XKeysymToKeycode(GDK_WINDOW_XDISPLAY(event->window), (KeySym)keyval);
5365     event->length = 0;
5366     event->string = NULL;
5367 
5368     gtk_im_context_filter_keypress(xic, event);
5369 
5370     /* For consistency, also send the corresponding release event. */
5371     event->type = GDK_KEY_RELEASE;
5372     event->send_event = FALSE;
5373     gtk_im_context_filter_keypress(xic, event);
5374 
5375 #  ifdef HAVE_GTK_MULTIHEAD
5376     gdk_event_free((GdkEvent *)event);
5377 #  else
5378     g_free(event);
5379 #  endif
5380 }
5381 
5382     void
5383 xim_reset(void)
5384 {
5385     if (xic != NULL)
5386     {
5387 	gtk_im_context_reset(xic);
5388 
5389 	if (p_imdisable)
5390 	    im_shutdown();
5391 	else
5392 	{
5393 	    xim_set_focus(gui.in_focus);
5394 
5395 #  ifdef FEAT_EVAL
5396 	    if (p_imaf[0] != NUL)
5397 	    {
5398 		char_u *argv[1];
5399 
5400 		if (im_is_active)
5401 		    argv[0] = (char_u *)"1";
5402 		else
5403 		    argv[0] = (char_u *)"0";
5404 		(void)call_func_retnr(p_imaf, 1, argv, FALSE);
5405 	    }
5406 	    else
5407 #  endif
5408 		if (im_activatekey_keyval != GDK_VoidSymbol)
5409 	    {
5410 		if (im_is_active)
5411 		{
5412 		    g_signal_handler_block(xic, im_commit_handler_id);
5413 		    im_synthesize_keypress(im_activatekey_keyval,
5414 						    im_activatekey_state);
5415 		    g_signal_handler_unblock(xic, im_commit_handler_id);
5416 		}
5417 	    }
5418 	    else
5419 	    {
5420 		im_shutdown();
5421 		xim_init();
5422 		xim_set_focus(gui.in_focus);
5423 	    }
5424 	}
5425     }
5426 
5427     preedit_start_col = MAXCOL;
5428     xim_has_preediting = FALSE;
5429 }
5430 
5431     int
5432 xim_queue_key_press_event(GdkEventKey *event, int down)
5433 {
5434     if (down)
5435     {
5436 	/*
5437 	 * Workaround GTK2 XIM 'feature' that always converts keypad keys to
5438 	 * chars., even when not part of an IM sequence (ref. feature of
5439 	 * gdk/gdkkeyuni.c).
5440 	 * Flag any keypad keys that might represent a single char.
5441 	 * If this (on its own - i.e., not part of an IM sequence) is
5442 	 * committed while we're processing one of these keys, we can ignore
5443 	 * that commit and go ahead & process it ourselves.  That way we can
5444 	 * still distinguish keypad keys for use in mappings.
5445 	 * Also add GDK_space to make <S-Space> work.
5446 	 */
5447 	switch (event->keyval)
5448 	{
5449 	    case GDK_KP_Add:      xim_expected_char = '+';  break;
5450 	    case GDK_KP_Subtract: xim_expected_char = '-';  break;
5451 	    case GDK_KP_Divide:   xim_expected_char = '/';  break;
5452 	    case GDK_KP_Multiply: xim_expected_char = '*';  break;
5453 	    case GDK_KP_Decimal:  xim_expected_char = '.';  break;
5454 	    case GDK_KP_Equal:    xim_expected_char = '=';  break;
5455 	    case GDK_KP_0:	  xim_expected_char = '0';  break;
5456 	    case GDK_KP_1:	  xim_expected_char = '1';  break;
5457 	    case GDK_KP_2:	  xim_expected_char = '2';  break;
5458 	    case GDK_KP_3:	  xim_expected_char = '3';  break;
5459 	    case GDK_KP_4:	  xim_expected_char = '4';  break;
5460 	    case GDK_KP_5:	  xim_expected_char = '5';  break;
5461 	    case GDK_KP_6:	  xim_expected_char = '6';  break;
5462 	    case GDK_KP_7:	  xim_expected_char = '7';  break;
5463 	    case GDK_KP_8:	  xim_expected_char = '8';  break;
5464 	    case GDK_KP_9:	  xim_expected_char = '9';  break;
5465 	    case GDK_space:	  xim_expected_char = ' ';  break;
5466 	    default:		  xim_expected_char = NUL;
5467 	}
5468 	xim_ignored_char = FALSE;
5469     }
5470 
5471     /*
5472      * When typing fFtT, XIM may be activated. Thus it must pass
5473      * gtk_im_context_filter_keypress() in Normal mode.
5474      * And while doing :sh too.
5475      */
5476     if (xic != NULL && !p_imdisable
5477 		    && (State & (INSERT | CMDLINE | NORMAL | EXTERNCMD)) != 0)
5478     {
5479 	/*
5480 	 * Filter 'imactivatekey' and map it to CTRL-^.  This way, Vim is
5481 	 * always aware of the current status of IM, and can even emulate
5482 	 * the activation key for modules that don't support one.
5483 	 */
5484 	if (event->keyval == im_activatekey_keyval
5485 	     && (event->state & im_activatekey_state) == im_activatekey_state)
5486 	{
5487 	    unsigned int state_mask;
5488 
5489 	    /* Require the state of the 3 most used modifiers to match exactly.
5490 	     * Otherwise e.g. <S-C-space> would be unusable for other purposes
5491 	     * if the IM activate key is <S-space>. */
5492 	    state_mask  = im_activatekey_state;
5493 	    state_mask |= ((int)GDK_SHIFT_MASK | (int)GDK_CONTROL_MASK
5494 							| (int)GDK_MOD1_MASK);
5495 
5496 	    if ((event->state & state_mask) != im_activatekey_state)
5497 		return FALSE;
5498 
5499 	    /* Don't send it a second time on GDK_KEY_RELEASE. */
5500 	    if (event->type != GDK_KEY_PRESS)
5501 		return TRUE;
5502 
5503 	    if (map_to_exists_mode((char_u *)"", LANGMAP, FALSE))
5504 	    {
5505 		im_set_active(FALSE);
5506 
5507 		/* ":lmap" mappings exists, toggle use of mappings. */
5508 		State ^= LANGMAP;
5509 		if (State & LANGMAP)
5510 		{
5511 		    curbuf->b_p_iminsert = B_IMODE_NONE;
5512 		    State &= ~LANGMAP;
5513 		}
5514 		else
5515 		{
5516 		    curbuf->b_p_iminsert = B_IMODE_LMAP;
5517 		    State |= LANGMAP;
5518 		}
5519 		return TRUE;
5520 	    }
5521 
5522 	    return gtk_im_context_filter_keypress(xic, event);
5523 	}
5524 
5525 	/* Don't filter events through the IM context if IM isn't active
5526 	 * right now.  Unlike with GTK+ 1.2 we cannot rely on the IM module
5527 	 * not doing anything before the activation key was sent. */
5528 	if (im_activatekey_keyval == GDK_VoidSymbol || im_is_active)
5529 	{
5530 	    int imresult = gtk_im_context_filter_keypress(xic, event);
5531 
5532 	    /* Some XIM send following sequence:
5533 	     * 1. preedited string.
5534 	     * 2. committed string.
5535 	     * 3. line changed key.
5536 	     * 4. preedited string.
5537 	     * 5. remove preedited string.
5538 	     * if 3, Vim can't move back the above line for 5.
5539 	     * thus, this part should not parse the key. */
5540 	    if (!imresult && preedit_start_col != MAXCOL
5541 					       && event->keyval == GDK_Return)
5542 	    {
5543 		im_synthesize_keypress(GDK_Return, 0U);
5544 		return FALSE;
5545 	    }
5546 
5547 	    /* If XIM tried to commit a keypad key as a single char.,
5548 	     * ignore it so we can use the keypad key 'raw', for mappings. */
5549 	    if (xim_expected_char != NUL && xim_ignored_char)
5550 		/* We had a keypad key, and XIM tried to thieve it */
5551 		return FALSE;
5552 
5553 	    /* This is supposed to fix a problem with iBus, that space
5554 	     * characters don't work in input mode. */
5555 	    xim_expected_char = NUL;
5556 
5557 	    /* Normal processing */
5558 	    return imresult;
5559 	}
5560     }
5561 
5562     return FALSE;
5563 }
5564 
5565     int
5566 im_get_status(void)
5567 {
5568 #  ifdef FEAT_EVAL
5569     if (p_imsf[0] != NUL)
5570     {
5571 	int is_active;
5572 
5573 	/* FIXME: Don't execute user function in unsafe situation. */
5574 	if (exiting
5575 #   ifdef FEAT_AUTOCMD
5576 		|| is_autocmd_blocked()
5577 #   endif
5578 		)
5579 	    return FALSE;
5580 	/* FIXME: :py print 'xxx' is shown duplicate result.
5581 	 * Use silent to avoid it. */
5582 	++msg_silent;
5583 	is_active = call_func_retnr(p_imsf, 0, NULL, FALSE);
5584 	--msg_silent;
5585 	return (is_active > 0);
5586     }
5587 #  endif
5588     return im_is_active;
5589 }
5590 
5591     int
5592 preedit_get_status(void)
5593 {
5594     return preedit_is_active;
5595 }
5596 
5597     int
5598 im_is_preediting(void)
5599 {
5600     return xim_has_preediting;
5601 }
5602 
5603 # else /* !FEAT_GUI_GTK */
5604 
5605 static int	xim_is_active = FALSE;  /* XIM should be active in the current
5606 					   mode */
5607 static int	xim_has_focus = FALSE;	/* XIM is really being used for Vim */
5608 #ifdef FEAT_GUI_X11
5609 static XIMStyle	input_style;
5610 static int	status_area_enabled = TRUE;
5611 #endif
5612 
5613 /*
5614  * Switch using XIM on/off.  This is used by the code that changes "State".
5615  */
5616     void
5617 im_set_active(int active)
5618 {
5619     if (xic == NULL)
5620 	return;
5621 
5622     /* If 'imdisable' is set, XIM is never active. */
5623     if (p_imdisable)
5624 	active = FALSE;
5625 #if !defined(FEAT_GUI_GTK)
5626     else if (input_style & XIMPreeditPosition)
5627 	/* There is a problem in switching XIM off when preediting is used,
5628 	 * and it is not clear how this can be solved.  For now, keep XIM on
5629 	 * all the time, like it was done in Vim 5.8. */
5630 	active = TRUE;
5631 #endif
5632 
5633     /* Remember the active state, it is needed when Vim gets keyboard focus. */
5634     xim_is_active = active;
5635     xim_set_preedit();
5636 }
5637 
5638 /*
5639  * Adjust using XIM for gaining or losing keyboard focus.  Also called when
5640  * "xim_is_active" changes.
5641  */
5642     void
5643 xim_set_focus(int focus)
5644 {
5645     if (xic == NULL)
5646 	return;
5647 
5648     /*
5649      * XIM only gets focus when the Vim window has keyboard focus and XIM has
5650      * been set active for the current mode.
5651      */
5652     if (focus && xim_is_active)
5653     {
5654 	if (!xim_has_focus)
5655 	{
5656 	    xim_has_focus = TRUE;
5657 	    XSetICFocus(xic);
5658 	}
5659     }
5660     else
5661     {
5662 	if (xim_has_focus)
5663 	{
5664 	    xim_has_focus = FALSE;
5665 	    XUnsetICFocus(xic);
5666 	}
5667     }
5668 }
5669 
5670     void
5671 im_set_position(int row UNUSED, int col UNUSED)
5672 {
5673     xim_set_preedit();
5674 }
5675 
5676 /*
5677  * Set the XIM to the current cursor position.
5678  */
5679     void
5680 xim_set_preedit(void)
5681 {
5682     XVaNestedList attr_list;
5683     XRectangle spot_area;
5684     XPoint over_spot;
5685     int line_space;
5686 
5687     if (xic == NULL)
5688 	return;
5689 
5690     xim_set_focus(TRUE);
5691 
5692     if (!xim_has_focus)
5693     {
5694 	/* hide XIM cursor */
5695 	over_spot.x = 0;
5696 	over_spot.y = -100; /* arbitrary invisible position */
5697 	attr_list = (XVaNestedList) XVaCreateNestedList(0,
5698 							XNSpotLocation,
5699 							&over_spot,
5700 							NULL);
5701 	XSetICValues(xic, XNPreeditAttributes, attr_list, NULL);
5702 	XFree(attr_list);
5703 	return;
5704     }
5705 
5706     if (input_style & XIMPreeditPosition)
5707     {
5708 	if (xim_fg_color == INVALCOLOR)
5709 	{
5710 	    xim_fg_color = gui.def_norm_pixel;
5711 	    xim_bg_color = gui.def_back_pixel;
5712 	}
5713 	over_spot.x = TEXT_X(gui.col);
5714 	over_spot.y = TEXT_Y(gui.row);
5715 	spot_area.x = 0;
5716 	spot_area.y = 0;
5717 	spot_area.height = gui.char_height * Rows;
5718 	spot_area.width  = gui.char_width * Columns;
5719 	line_space = gui.char_height;
5720 	attr_list = (XVaNestedList) XVaCreateNestedList(0,
5721 					XNSpotLocation, &over_spot,
5722 					XNForeground, (Pixel) xim_fg_color,
5723 					XNBackground, (Pixel) xim_bg_color,
5724 					XNArea, &spot_area,
5725 					XNLineSpace, line_space,
5726 					NULL);
5727 	if (XSetICValues(xic, XNPreeditAttributes, attr_list, NULL))
5728 	    EMSG(_("E284: Cannot set IC values"));
5729 	XFree(attr_list);
5730     }
5731 }
5732 
5733 #if defined(FEAT_GUI_X11)
5734 static char e_xim[] = N_("E285: Failed to create input context");
5735 #endif
5736 
5737 #if defined(FEAT_GUI_X11) || defined(PROTO)
5738 # if defined(XtSpecificationRelease) && XtSpecificationRelease >= 6 && !defined(sun)
5739 #  define USE_X11R6_XIM
5740 # endif
5741 
5742 static int xim_real_init(Window x11_window, Display *x11_display);
5743 
5744 
5745 #ifdef USE_X11R6_XIM
5746 static void xim_instantiate_cb(Display *display, XPointer client_data, XPointer	call_data);
5747 static void xim_destroy_cb(XIM im, XPointer client_data, XPointer call_data);
5748 
5749     static void
5750 xim_instantiate_cb(
5751     Display	*display,
5752     XPointer	client_data UNUSED,
5753     XPointer	call_data UNUSED)
5754 {
5755     Window	x11_window;
5756     Display	*x11_display;
5757 
5758 #ifdef XIM_DEBUG
5759     xim_log("xim_instantiate_cb()\n");
5760 #endif
5761 
5762     gui_get_x11_windis(&x11_window, &x11_display);
5763     if (display != x11_display)
5764 	return;
5765 
5766     xim_real_init(x11_window, x11_display);
5767     gui_set_shellsize(FALSE, FALSE, RESIZE_BOTH);
5768     if (xic != NULL)
5769 	XUnregisterIMInstantiateCallback(x11_display, NULL, NULL, NULL,
5770 					 xim_instantiate_cb, NULL);
5771 }
5772 
5773     static void
5774 xim_destroy_cb(
5775     XIM		im UNUSED,
5776     XPointer	client_data UNUSED,
5777     XPointer	call_data UNUSED)
5778 {
5779     Window	x11_window;
5780     Display	*x11_display;
5781 
5782 #ifdef XIM_DEBUG
5783     xim_log("xim_destroy_cb()\n");
5784 #endif
5785     gui_get_x11_windis(&x11_window, &x11_display);
5786 
5787     xic = NULL;
5788     status_area_enabled = FALSE;
5789 
5790     gui_set_shellsize(FALSE, FALSE, RESIZE_BOTH);
5791 
5792     XRegisterIMInstantiateCallback(x11_display, NULL, NULL, NULL,
5793 				   xim_instantiate_cb, NULL);
5794 }
5795 #endif
5796 
5797     void
5798 xim_init(void)
5799 {
5800     Window	x11_window;
5801     Display	*x11_display;
5802 
5803 #ifdef XIM_DEBUG
5804     xim_log("xim_init()\n");
5805 #endif
5806 
5807     gui_get_x11_windis(&x11_window, &x11_display);
5808 
5809     xic = NULL;
5810 
5811     if (xim_real_init(x11_window, x11_display))
5812 	return;
5813 
5814     gui_set_shellsize(FALSE, FALSE, RESIZE_BOTH);
5815 
5816 #ifdef USE_X11R6_XIM
5817     XRegisterIMInstantiateCallback(x11_display, NULL, NULL, NULL,
5818 				   xim_instantiate_cb, NULL);
5819 #endif
5820 }
5821 
5822     static int
5823 xim_real_init(Window x11_window, Display *x11_display)
5824 {
5825     int		i;
5826     char	*p,
5827 		*s,
5828 		*ns,
5829 		*end,
5830 		tmp[1024];
5831 #define IMLEN_MAX 40
5832     char	buf[IMLEN_MAX + 7];
5833     XIM		xim = NULL;
5834     XIMStyles	*xim_styles;
5835     XIMStyle	this_input_style = 0;
5836     Boolean	found;
5837     XPoint	over_spot;
5838     XVaNestedList preedit_list, status_list;
5839 
5840     input_style = 0;
5841     status_area_enabled = FALSE;
5842 
5843     if (xic != NULL)
5844 	return FALSE;
5845 
5846     if (gui.rsrc_input_method != NULL && *gui.rsrc_input_method != NUL)
5847     {
5848 	strcpy(tmp, gui.rsrc_input_method);
5849 	for (ns = s = tmp; ns != NULL && *s != NUL;)
5850 	{
5851 	    s = (char *)skipwhite((char_u *)s);
5852 	    if (*s == NUL)
5853 		break;
5854 	    if ((ns = end = strchr(s, ',')) == NULL)
5855 		end = s + strlen(s);
5856 	    while (isspace(((char_u *)end)[-1]))
5857 		end--;
5858 	    *end = NUL;
5859 
5860 	    if (strlen(s) <= IMLEN_MAX)
5861 	    {
5862 		strcpy(buf, "@im=");
5863 		strcat(buf, s);
5864 		if ((p = XSetLocaleModifiers(buf)) != NULL && *p != NUL
5865 			&& (xim = XOpenIM(x11_display, NULL, NULL, NULL))
5866 								      != NULL)
5867 		    break;
5868 	    }
5869 
5870 	    s = ns + 1;
5871 	}
5872     }
5873 
5874     if (xim == NULL && (p = XSetLocaleModifiers("")) != NULL && *p != NUL)
5875 	xim = XOpenIM(x11_display, NULL, NULL, NULL);
5876 
5877     /* This is supposed to be useful to obtain characters through
5878      * XmbLookupString() without really using a XIM. */
5879     if (xim == NULL && (p = XSetLocaleModifiers("@im=none")) != NULL
5880 								 && *p != NUL)
5881 	xim = XOpenIM(x11_display, NULL, NULL, NULL);
5882 
5883     if (xim == NULL)
5884     {
5885 	/* Only give this message when verbose is set, because too many people
5886 	 * got this message when they didn't want to use a XIM. */
5887 	if (p_verbose > 0)
5888 	{
5889 	    verbose_enter();
5890 	    EMSG(_("E286: Failed to open input method"));
5891 	    verbose_leave();
5892 	}
5893 	return FALSE;
5894     }
5895 
5896 #ifdef USE_X11R6_XIM
5897     {
5898 	XIMCallback destroy_cb;
5899 
5900 	destroy_cb.callback = xim_destroy_cb;
5901 	destroy_cb.client_data = NULL;
5902 	if (XSetIMValues(xim, XNDestroyCallback, &destroy_cb, NULL))
5903 	    EMSG(_("E287: Warning: Could not set destroy callback to IM"));
5904     }
5905 #endif
5906 
5907     if (XGetIMValues(xim, XNQueryInputStyle, &xim_styles, NULL) || !xim_styles)
5908     {
5909 	EMSG(_("E288: input method doesn't support any style"));
5910 	XCloseIM(xim);
5911 	return FALSE;
5912     }
5913 
5914     found = False;
5915     strcpy(tmp, gui.rsrc_preedit_type_name);
5916     for (s = tmp; s && !found; )
5917     {
5918 	while (*s && isspace((unsigned char)*s))
5919 	    s++;
5920 	if (!*s)
5921 	    break;
5922 	if ((ns = end = strchr(s, ',')) != 0)
5923 	    ns++;
5924 	else
5925 	    end = s + strlen(s);
5926 	while (isspace((unsigned char)*end))
5927 	    end--;
5928 	*end = '\0';
5929 
5930 	if (!strcmp(s, "OverTheSpot"))
5931 	    this_input_style = (XIMPreeditPosition | XIMStatusArea);
5932 	else if (!strcmp(s, "OffTheSpot"))
5933 	    this_input_style = (XIMPreeditArea | XIMStatusArea);
5934 	else if (!strcmp(s, "Root"))
5935 	    this_input_style = (XIMPreeditNothing | XIMStatusNothing);
5936 
5937 	for (i = 0; (unsigned short)i < xim_styles->count_styles; i++)
5938 	{
5939 	    if (this_input_style == xim_styles->supported_styles[i])
5940 	    {
5941 		found = True;
5942 		break;
5943 	    }
5944 	}
5945 	if (!found)
5946 	    for (i = 0; (unsigned short)i < xim_styles->count_styles; i++)
5947 	    {
5948 		if ((xim_styles->supported_styles[i] & this_input_style)
5949 			== (this_input_style & ~XIMStatusArea))
5950 		{
5951 		    this_input_style &= ~XIMStatusArea;
5952 		    found = True;
5953 		    break;
5954 		}
5955 	    }
5956 
5957 	s = ns;
5958     }
5959     XFree(xim_styles);
5960 
5961     if (!found)
5962     {
5963 	/* Only give this message when verbose is set, because too many people
5964 	 * got this message when they didn't want to use a XIM. */
5965 	if (p_verbose > 0)
5966 	{
5967 	    verbose_enter();
5968 	    EMSG(_("E289: input method doesn't support my preedit type"));
5969 	    verbose_leave();
5970 	}
5971 	XCloseIM(xim);
5972 	return FALSE;
5973     }
5974 
5975     over_spot.x = TEXT_X(gui.col);
5976     over_spot.y = TEXT_Y(gui.row);
5977     input_style = this_input_style;
5978 
5979     /* A crash was reported when trying to pass gui.norm_font as XNFontSet,
5980      * thus that has been removed.  Hopefully the default works... */
5981 #ifdef FEAT_XFONTSET
5982     if (gui.fontset != NOFONTSET)
5983     {
5984 	preedit_list = XVaCreateNestedList(0,
5985 				XNSpotLocation, &over_spot,
5986 				XNForeground, (Pixel)gui.def_norm_pixel,
5987 				XNBackground, (Pixel)gui.def_back_pixel,
5988 				XNFontSet, (XFontSet)gui.fontset,
5989 				NULL);
5990 	status_list = XVaCreateNestedList(0,
5991 				XNForeground, (Pixel)gui.def_norm_pixel,
5992 				XNBackground, (Pixel)gui.def_back_pixel,
5993 				XNFontSet, (XFontSet)gui.fontset,
5994 				NULL);
5995     }
5996     else
5997 #endif
5998     {
5999 	preedit_list = XVaCreateNestedList(0,
6000 				XNSpotLocation, &over_spot,
6001 				XNForeground, (Pixel)gui.def_norm_pixel,
6002 				XNBackground, (Pixel)gui.def_back_pixel,
6003 				NULL);
6004 	status_list = XVaCreateNestedList(0,
6005 				XNForeground, (Pixel)gui.def_norm_pixel,
6006 				XNBackground, (Pixel)gui.def_back_pixel,
6007 				NULL);
6008     }
6009 
6010     xic = XCreateIC(xim,
6011 		    XNInputStyle, input_style,
6012 		    XNClientWindow, x11_window,
6013 		    XNFocusWindow, gui.wid,
6014 		    XNPreeditAttributes, preedit_list,
6015 		    XNStatusAttributes, status_list,
6016 		    NULL);
6017     XFree(status_list);
6018     XFree(preedit_list);
6019     if (xic != NULL)
6020     {
6021 	if (input_style & XIMStatusArea)
6022 	{
6023 	    xim_set_status_area();
6024 	    status_area_enabled = TRUE;
6025 	}
6026 	else
6027 	    gui_set_shellsize(FALSE, FALSE, RESIZE_BOTH);
6028     }
6029     else
6030     {
6031 	EMSG(_(e_xim));
6032 	XCloseIM(xim);
6033 	return FALSE;
6034     }
6035 
6036     return TRUE;
6037 }
6038 
6039 #endif /* FEAT_GUI_X11 */
6040 
6041 /*
6042  * Get IM status.  When IM is on, return TRUE.  Else return FALSE.
6043  * FIXME: This doesn't work correctly: Having focus doesn't always mean XIM is
6044  * active, when not having focus XIM may still be active (e.g., when using a
6045  * tear-off menu item).
6046  */
6047     int
6048 im_get_status(void)
6049 {
6050     return xim_has_focus;
6051 }
6052 
6053 # endif /* !FEAT_GUI_GTK */
6054 
6055 # if !defined(FEAT_GUI_GTK) || defined(PROTO)
6056 /*
6057  * Set up the status area.
6058  *
6059  * This should use a separate Widget, but that seems not possible, because
6060  * preedit_area and status_area should be set to the same window as for the
6061  * text input.  Unfortunately this means the status area pollutes the text
6062  * window...
6063  */
6064     void
6065 xim_set_status_area(void)
6066 {
6067     XVaNestedList preedit_list = 0, status_list = 0, list = 0;
6068     XRectangle pre_area, status_area;
6069 
6070     if (xic == NULL)
6071 	return;
6072 
6073     if (input_style & XIMStatusArea)
6074     {
6075 	if (input_style & XIMPreeditArea)
6076 	{
6077 	    XRectangle *needed_rect;
6078 
6079 	    /* to get status_area width */
6080 	    status_list = XVaCreateNestedList(0, XNAreaNeeded,
6081 					      &needed_rect, NULL);
6082 	    XGetICValues(xic, XNStatusAttributes, status_list, NULL);
6083 	    XFree(status_list);
6084 
6085 	    status_area.width = needed_rect->width;
6086 	}
6087 	else
6088 	    status_area.width = gui.char_width * Columns;
6089 
6090 	status_area.x = 0;
6091 	status_area.y = gui.char_height * Rows + gui.border_offset;
6092 	if (gui.which_scrollbars[SBAR_BOTTOM])
6093 	    status_area.y += gui.scrollbar_height;
6094 #ifdef FEAT_MENU
6095 	if (gui.menu_is_active)
6096 	    status_area.y += gui.menu_height;
6097 #endif
6098 	status_area.height = gui.char_height;
6099 	status_list = XVaCreateNestedList(0, XNArea, &status_area, NULL);
6100     }
6101     else
6102     {
6103 	status_area.x = 0;
6104 	status_area.y = gui.char_height * Rows + gui.border_offset;
6105 	if (gui.which_scrollbars[SBAR_BOTTOM])
6106 	    status_area.y += gui.scrollbar_height;
6107 #ifdef FEAT_MENU
6108 	if (gui.menu_is_active)
6109 	    status_area.y += gui.menu_height;
6110 #endif
6111 	status_area.width = 0;
6112 	status_area.height = gui.char_height;
6113     }
6114 
6115     if (input_style & XIMPreeditArea)   /* off-the-spot */
6116     {
6117 	pre_area.x = status_area.x + status_area.width;
6118 	pre_area.y = gui.char_height * Rows + gui.border_offset;
6119 	pre_area.width = gui.char_width * Columns - pre_area.x;
6120 	if (gui.which_scrollbars[SBAR_BOTTOM])
6121 	    pre_area.y += gui.scrollbar_height;
6122 #ifdef FEAT_MENU
6123 	if (gui.menu_is_active)
6124 	    pre_area.y += gui.menu_height;
6125 #endif
6126 	pre_area.height = gui.char_height;
6127 	preedit_list = XVaCreateNestedList(0, XNArea, &pre_area, NULL);
6128     }
6129     else if (input_style & XIMPreeditPosition)   /* over-the-spot */
6130     {
6131 	pre_area.x = 0;
6132 	pre_area.y = 0;
6133 	pre_area.height = gui.char_height * Rows;
6134 	pre_area.width = gui.char_width * Columns;
6135 	preedit_list = XVaCreateNestedList(0, XNArea, &pre_area, NULL);
6136     }
6137 
6138     if (preedit_list && status_list)
6139 	list = XVaCreateNestedList(0, XNPreeditAttributes, preedit_list,
6140 				   XNStatusAttributes, status_list, NULL);
6141     else if (preedit_list)
6142 	list = XVaCreateNestedList(0, XNPreeditAttributes, preedit_list,
6143 				   NULL);
6144     else if (status_list)
6145 	list = XVaCreateNestedList(0, XNStatusAttributes, status_list,
6146 				   NULL);
6147     else
6148 	list = NULL;
6149 
6150     if (list)
6151     {
6152 	XSetICValues(xic, XNVaNestedList, list, NULL);
6153 	XFree(list);
6154     }
6155     if (status_list)
6156 	XFree(status_list);
6157     if (preedit_list)
6158 	XFree(preedit_list);
6159 }
6160 
6161     int
6162 xim_get_status_area_height(void)
6163 {
6164     if (status_area_enabled)
6165 	return gui.char_height;
6166     return 0;
6167 }
6168 # endif
6169 
6170 #endif /* FEAT_XIM */
6171 
6172 #if defined(FEAT_MBYTE) || defined(PROTO)
6173 
6174 /*
6175  * Setup "vcp" for conversion from "from" to "to".
6176  * The names must have been made canonical with enc_canonize().
6177  * vcp->vc_type must have been initialized to CONV_NONE.
6178  * Note: cannot be used for conversion from/to ucs-2 and ucs-4 (will use utf-8
6179  * instead).
6180  * Afterwards invoke with "from" and "to" equal to NULL to cleanup.
6181  * Return FAIL when conversion is not supported, OK otherwise.
6182  */
6183     int
6184 convert_setup(vimconv_T *vcp, char_u *from, char_u *to)
6185 {
6186     return convert_setup_ext(vcp, from, TRUE, to, TRUE);
6187 }
6188 
6189 /*
6190  * As convert_setup(), but only when from_unicode_is_utf8 is TRUE will all
6191  * "from" unicode charsets be considered utf-8.  Same for "to".
6192  */
6193     int
6194 convert_setup_ext(
6195     vimconv_T	*vcp,
6196     char_u	*from,
6197     int		from_unicode_is_utf8,
6198     char_u	*to,
6199     int		to_unicode_is_utf8)
6200 {
6201     int		from_prop;
6202     int		to_prop;
6203     int		from_is_utf8;
6204     int		to_is_utf8;
6205 
6206     /* Reset to no conversion. */
6207 # ifdef USE_ICONV
6208     if (vcp->vc_type == CONV_ICONV && vcp->vc_fd != (iconv_t)-1)
6209 	iconv_close(vcp->vc_fd);
6210 # endif
6211     vcp->vc_type = CONV_NONE;
6212     vcp->vc_factor = 1;
6213     vcp->vc_fail = FALSE;
6214 
6215     /* No conversion when one of the names is empty or they are equal. */
6216     if (from == NULL || *from == NUL || to == NULL || *to == NUL
6217 						     || STRCMP(from, to) == 0)
6218 	return OK;
6219 
6220     from_prop = enc_canon_props(from);
6221     to_prop = enc_canon_props(to);
6222     if (from_unicode_is_utf8)
6223 	from_is_utf8 = from_prop & ENC_UNICODE;
6224     else
6225 	from_is_utf8 = from_prop == ENC_UNICODE;
6226     if (to_unicode_is_utf8)
6227 	to_is_utf8 = to_prop & ENC_UNICODE;
6228     else
6229 	to_is_utf8 = to_prop == ENC_UNICODE;
6230 
6231     if ((from_prop & ENC_LATIN1) && to_is_utf8)
6232     {
6233 	/* Internal latin1 -> utf-8 conversion. */
6234 	vcp->vc_type = CONV_TO_UTF8;
6235 	vcp->vc_factor = 2;	/* up to twice as long */
6236     }
6237     else if ((from_prop & ENC_LATIN9) && to_is_utf8)
6238     {
6239 	/* Internal latin9 -> utf-8 conversion. */
6240 	vcp->vc_type = CONV_9_TO_UTF8;
6241 	vcp->vc_factor = 3;	/* up to three as long (euro sign) */
6242     }
6243     else if (from_is_utf8 && (to_prop & ENC_LATIN1))
6244     {
6245 	/* Internal utf-8 -> latin1 conversion. */
6246 	vcp->vc_type = CONV_TO_LATIN1;
6247     }
6248     else if (from_is_utf8 && (to_prop & ENC_LATIN9))
6249     {
6250 	/* Internal utf-8 -> latin9 conversion. */
6251 	vcp->vc_type = CONV_TO_LATIN9;
6252     }
6253 #ifdef WIN3264
6254     /* Win32-specific codepage <-> codepage conversion without iconv. */
6255     else if ((from_is_utf8 || encname2codepage(from) > 0)
6256 	    && (to_is_utf8 || encname2codepage(to) > 0))
6257     {
6258 	vcp->vc_type = CONV_CODEPAGE;
6259 	vcp->vc_factor = 2;	/* up to twice as long */
6260 	vcp->vc_cpfrom = from_is_utf8 ? 0 : encname2codepage(from);
6261 	vcp->vc_cpto = to_is_utf8 ? 0 : encname2codepage(to);
6262     }
6263 #endif
6264 #ifdef MACOS_X
6265     else if ((from_prop & ENC_MACROMAN) && (to_prop & ENC_LATIN1))
6266     {
6267 	vcp->vc_type = CONV_MAC_LATIN1;
6268     }
6269     else if ((from_prop & ENC_MACROMAN) && to_is_utf8)
6270     {
6271 	vcp->vc_type = CONV_MAC_UTF8;
6272 	vcp->vc_factor = 2;	/* up to twice as long */
6273     }
6274     else if ((from_prop & ENC_LATIN1) && (to_prop & ENC_MACROMAN))
6275     {
6276 	vcp->vc_type = CONV_LATIN1_MAC;
6277     }
6278     else if (from_is_utf8 && (to_prop & ENC_MACROMAN))
6279     {
6280 	vcp->vc_type = CONV_UTF8_MAC;
6281     }
6282 #endif
6283 # ifdef USE_ICONV
6284     else
6285     {
6286 	/* Use iconv() for conversion. */
6287 	vcp->vc_fd = (iconv_t)my_iconv_open(
6288 		to_is_utf8 ? (char_u *)"utf-8" : to,
6289 		from_is_utf8 ? (char_u *)"utf-8" : from);
6290 	if (vcp->vc_fd != (iconv_t)-1)
6291 	{
6292 	    vcp->vc_type = CONV_ICONV;
6293 	    vcp->vc_factor = 4;	/* could be longer too... */
6294 	}
6295     }
6296 # endif
6297     if (vcp->vc_type == CONV_NONE)
6298 	return FAIL;
6299 
6300     return OK;
6301 }
6302 
6303 #if defined(FEAT_GUI) || defined(AMIGA) || defined(WIN3264) \
6304 	|| defined(PROTO)
6305 /*
6306  * Do conversion on typed input characters in-place.
6307  * The input and output are not NUL terminated!
6308  * Returns the length after conversion.
6309  */
6310     int
6311 convert_input(char_u *ptr, int len, int maxlen)
6312 {
6313     return convert_input_safe(ptr, len, maxlen, NULL, NULL);
6314 }
6315 #endif
6316 
6317 /*
6318  * Like convert_input(), but when there is an incomplete byte sequence at the
6319  * end return that as an allocated string in "restp" and set "*restlenp" to
6320  * the length.  If "restp" is NULL it is not used.
6321  */
6322     int
6323 convert_input_safe(
6324     char_u	*ptr,
6325     int		len,
6326     int		maxlen,
6327     char_u	**restp,
6328     int		*restlenp)
6329 {
6330     char_u	*d;
6331     int		dlen = len;
6332     int		unconvertlen = 0;
6333 
6334     d = string_convert_ext(&input_conv, ptr, &dlen,
6335 					restp == NULL ? NULL : &unconvertlen);
6336     if (d != NULL)
6337     {
6338 	if (dlen <= maxlen)
6339 	{
6340 	    if (unconvertlen > 0)
6341 	    {
6342 		/* Move the unconverted characters to allocated memory. */
6343 		*restp = alloc(unconvertlen);
6344 		if (*restp != NULL)
6345 		    mch_memmove(*restp, ptr + len - unconvertlen, unconvertlen);
6346 		*restlenp = unconvertlen;
6347 	    }
6348 	    mch_memmove(ptr, d, dlen);
6349 	}
6350 	else
6351 	    /* result is too long, keep the unconverted text (the caller must
6352 	     * have done something wrong!) */
6353 	    dlen = len;
6354 	vim_free(d);
6355     }
6356     return dlen;
6357 }
6358 
6359 /*
6360  * Convert text "ptr[*lenp]" according to "vcp".
6361  * Returns the result in allocated memory and sets "*lenp".
6362  * When "lenp" is NULL, use NUL terminated strings.
6363  * Illegal chars are often changed to "?", unless vcp->vc_fail is set.
6364  * When something goes wrong, NULL is returned and "*lenp" is unchanged.
6365  */
6366     char_u *
6367 string_convert(
6368     vimconv_T	*vcp,
6369     char_u	*ptr,
6370     int		*lenp)
6371 {
6372     return string_convert_ext(vcp, ptr, lenp, NULL);
6373 }
6374 
6375 /*
6376  * Like string_convert(), but when "unconvlenp" is not NULL and there are is
6377  * an incomplete sequence at the end it is not converted and "*unconvlenp" is
6378  * set to the number of remaining bytes.
6379  */
6380     char_u *
6381 string_convert_ext(
6382     vimconv_T	*vcp,
6383     char_u	*ptr,
6384     int		*lenp,
6385     int		*unconvlenp)
6386 {
6387     char_u	*retval = NULL;
6388     char_u	*d;
6389     int		len;
6390     int		i;
6391     int		l;
6392     int		c;
6393 
6394     if (lenp == NULL)
6395 	len = (int)STRLEN(ptr);
6396     else
6397 	len = *lenp;
6398     if (len == 0)
6399 	return vim_strsave((char_u *)"");
6400 
6401     switch (vcp->vc_type)
6402     {
6403 	case CONV_TO_UTF8:	/* latin1 to utf-8 conversion */
6404 	    retval = alloc(len * 2 + 1);
6405 	    if (retval == NULL)
6406 		break;
6407 	    d = retval;
6408 	    for (i = 0; i < len; ++i)
6409 	    {
6410 		c = ptr[i];
6411 		if (c < 0x80)
6412 		    *d++ = c;
6413 		else
6414 		{
6415 		    *d++ = 0xc0 + ((unsigned)c >> 6);
6416 		    *d++ = 0x80 + (c & 0x3f);
6417 		}
6418 	    }
6419 	    *d = NUL;
6420 	    if (lenp != NULL)
6421 		*lenp = (int)(d - retval);
6422 	    break;
6423 
6424 	case CONV_9_TO_UTF8:	/* latin9 to utf-8 conversion */
6425 	    retval = alloc(len * 3 + 1);
6426 	    if (retval == NULL)
6427 		break;
6428 	    d = retval;
6429 	    for (i = 0; i < len; ++i)
6430 	    {
6431 		c = ptr[i];
6432 		switch (c)
6433 		{
6434 		    case 0xa4: c = 0x20ac; break;   /* euro */
6435 		    case 0xa6: c = 0x0160; break;   /* S hat */
6436 		    case 0xa8: c = 0x0161; break;   /* S -hat */
6437 		    case 0xb4: c = 0x017d; break;   /* Z hat */
6438 		    case 0xb8: c = 0x017e; break;   /* Z -hat */
6439 		    case 0xbc: c = 0x0152; break;   /* OE */
6440 		    case 0xbd: c = 0x0153; break;   /* oe */
6441 		    case 0xbe: c = 0x0178; break;   /* Y */
6442 		}
6443 		d += utf_char2bytes(c, d);
6444 	    }
6445 	    *d = NUL;
6446 	    if (lenp != NULL)
6447 		*lenp = (int)(d - retval);
6448 	    break;
6449 
6450 	case CONV_TO_LATIN1:	/* utf-8 to latin1 conversion */
6451 	case CONV_TO_LATIN9:	/* utf-8 to latin9 conversion */
6452 	    retval = alloc(len + 1);
6453 	    if (retval == NULL)
6454 		break;
6455 	    d = retval;
6456 	    for (i = 0; i < len; ++i)
6457 	    {
6458 		l = utf_ptr2len_len(ptr + i, len - i);
6459 		if (l == 0)
6460 		    *d++ = NUL;
6461 		else if (l == 1)
6462 		{
6463 		    int l_w = utf8len_tab_zero[ptr[i]];
6464 
6465 		    if (l_w == 0)
6466 		    {
6467 			/* Illegal utf-8 byte cannot be converted */
6468 			vim_free(retval);
6469 			return NULL;
6470 		    }
6471 		    if (unconvlenp != NULL && l_w > len - i)
6472 		    {
6473 			/* Incomplete sequence at the end. */
6474 			*unconvlenp = len - i;
6475 			break;
6476 		    }
6477 		    *d++ = ptr[i];
6478 		}
6479 		else
6480 		{
6481 		    c = utf_ptr2char(ptr + i);
6482 		    if (vcp->vc_type == CONV_TO_LATIN9)
6483 			switch (c)
6484 			{
6485 			    case 0x20ac: c = 0xa4; break;   /* euro */
6486 			    case 0x0160: c = 0xa6; break;   /* S hat */
6487 			    case 0x0161: c = 0xa8; break;   /* S -hat */
6488 			    case 0x017d: c = 0xb4; break;   /* Z hat */
6489 			    case 0x017e: c = 0xb8; break;   /* Z -hat */
6490 			    case 0x0152: c = 0xbc; break;   /* OE */
6491 			    case 0x0153: c = 0xbd; break;   /* oe */
6492 			    case 0x0178: c = 0xbe; break;   /* Y */
6493 			    case 0xa4:
6494 			    case 0xa6:
6495 			    case 0xa8:
6496 			    case 0xb4:
6497 			    case 0xb8:
6498 			    case 0xbc:
6499 			    case 0xbd:
6500 			    case 0xbe: c = 0x100; break; /* not in latin9 */
6501 			}
6502 		    if (!utf_iscomposing(c))	/* skip composing chars */
6503 		    {
6504 			if (c < 0x100)
6505 			    *d++ = c;
6506 			else if (vcp->vc_fail)
6507 			{
6508 			    vim_free(retval);
6509 			    return NULL;
6510 			}
6511 			else
6512 			{
6513 			    *d++ = 0xbf;
6514 			    if (utf_char2cells(c) > 1)
6515 				*d++ = '?';
6516 			}
6517 		    }
6518 		    i += l - 1;
6519 		}
6520 	    }
6521 	    *d = NUL;
6522 	    if (lenp != NULL)
6523 		*lenp = (int)(d - retval);
6524 	    break;
6525 
6526 # ifdef MACOS_CONVERT
6527 	case CONV_MAC_LATIN1:
6528 	    retval = mac_string_convert(ptr, len, lenp, vcp->vc_fail,
6529 					'm', 'l', unconvlenp);
6530 	    break;
6531 
6532 	case CONV_LATIN1_MAC:
6533 	    retval = mac_string_convert(ptr, len, lenp, vcp->vc_fail,
6534 					'l', 'm', unconvlenp);
6535 	    break;
6536 
6537 	case CONV_MAC_UTF8:
6538 	    retval = mac_string_convert(ptr, len, lenp, vcp->vc_fail,
6539 					'm', 'u', unconvlenp);
6540 	    break;
6541 
6542 	case CONV_UTF8_MAC:
6543 	    retval = mac_string_convert(ptr, len, lenp, vcp->vc_fail,
6544 					'u', 'm', unconvlenp);
6545 	    break;
6546 # endif
6547 
6548 # ifdef USE_ICONV
6549 	case CONV_ICONV:	/* conversion with output_conv.vc_fd */
6550 	    retval = iconv_string(vcp, ptr, len, unconvlenp, lenp);
6551 	    break;
6552 # endif
6553 # ifdef WIN3264
6554 	case CONV_CODEPAGE:		/* codepage -> codepage */
6555 	{
6556 	    int		retlen;
6557 	    int		tmp_len;
6558 	    short_u	*tmp;
6559 
6560 	    /* 1. codepage/UTF-8  ->  ucs-2. */
6561 	    if (vcp->vc_cpfrom == 0)
6562 		tmp_len = utf8_to_utf16(ptr, len, NULL, NULL);
6563 	    else
6564 	    {
6565 		tmp_len = MultiByteToWideChar(vcp->vc_cpfrom,
6566 					unconvlenp ? MB_ERR_INVALID_CHARS : 0,
6567 					(char *)ptr, len, 0, 0);
6568 		if (tmp_len == 0
6569 			&& GetLastError() == ERROR_NO_UNICODE_TRANSLATION)
6570 		{
6571 		    if (lenp != NULL)
6572 			*lenp = 0;
6573 		    if (unconvlenp != NULL)
6574 			*unconvlenp = len;
6575 		    retval = alloc(1);
6576 		    if (retval)
6577 			retval[0] = NUL;
6578 		    return retval;
6579 		}
6580 	    }
6581 	    tmp = (short_u *)alloc(sizeof(short_u) * tmp_len);
6582 	    if (tmp == NULL)
6583 		break;
6584 	    if (vcp->vc_cpfrom == 0)
6585 		utf8_to_utf16(ptr, len, tmp, unconvlenp);
6586 	    else
6587 		MultiByteToWideChar(vcp->vc_cpfrom, 0,
6588 			(char *)ptr, len, tmp, tmp_len);
6589 
6590 	    /* 2. ucs-2  ->  codepage/UTF-8. */
6591 	    if (vcp->vc_cpto == 0)
6592 		retlen = utf16_to_utf8(tmp, tmp_len, NULL);
6593 	    else
6594 		retlen = WideCharToMultiByte(vcp->vc_cpto, 0,
6595 						    tmp, tmp_len, 0, 0, 0, 0);
6596 	    retval = alloc(retlen + 1);
6597 	    if (retval != NULL)
6598 	    {
6599 		if (vcp->vc_cpto == 0)
6600 		    utf16_to_utf8(tmp, tmp_len, retval);
6601 		else
6602 		    WideCharToMultiByte(vcp->vc_cpto, 0,
6603 					  tmp, tmp_len,
6604 					  (char *)retval, retlen, 0, 0);
6605 		retval[retlen] = NUL;
6606 		if (lenp != NULL)
6607 		    *lenp = retlen;
6608 	    }
6609 	    vim_free(tmp);
6610 	    break;
6611 	}
6612 # endif
6613     }
6614 
6615     return retval;
6616 }
6617 #endif
6618