xref: /vim-8.2.3635/src/winclip.c (revision ba3ff539)
1 /* vi:set ts=8 sts=4 sw=4 noet:
2  *
3  * VIM - Vi IMproved by Bram Moolenaar
4  *
5  * Do ":help uganda"  in Vim to read copying and usage conditions.
6  * Do ":help credits" in Vim to see a list of people who contributed.
7  * See README.txt for an overview of the Vim source code.
8  */
9 
10 /*
11  * winclip.c
12  *
13  * Routines for Win32 clipboard handling.
14  * Also used by Cygwin, using os_unix.c.
15  */
16 
17 #include "vimio.h"
18 #include "vim.h"
19 
20 /*
21  * Compile only the clipboard handling features when compiling for cygwin
22  * posix environment.
23  */
24 #ifdef FEAT_CYGWIN_WIN32_CLIPBOARD
25 # define WIN3264
26 # define WIN32_LEAN_AND_MEAN
27 # include <windows.h>
28 # include "winclip.pro"
29 #endif
30 
31 /*
32  * When generating prototypes for Win32 on Unix, these lines make the syntax
33  * errors disappear.  They do not need to be correct.
34  */
35 #ifdef PROTO
36 #define WINAPI
37 #define WINBASEAPI
38 typedef int DWORD;
39 typedef int LPBOOL;
40 typedef int LPCSTR;
41 typedef int LPCWSTR;
42 typedef int LPSTR;
43 typedef int LPWSTR;
44 typedef int UINT;
45 #endif
46 
47 #if defined(FEAT_MBYTE) || defined(PROTO)
48 /*
49  * Convert an UTF-8 string to UTF-16.
50  * "instr[inlen]" is the input.  "inlen" is in bytes.
51  * When "outstr" is NULL only return the number of UTF-16 words produced.
52  * Otherwise "outstr" must be a buffer of sufficient size.
53  * Returns the number of UTF-16 words produced.
54  */
55     int
56 utf8_to_utf16(char_u *instr, int inlen, short_u *outstr, int *unconvlenp)
57 {
58     int		outlen = 0;
59     char_u	*p = instr;
60     int		todo = inlen;
61     int		l;
62     int		ch;
63 
64     while (todo > 0)
65     {
66 	/* Only convert if we have a complete sequence. */
67 	l = utf_ptr2len_len(p, todo);
68 	if (l > todo)
69 	{
70 	    /* Return length of incomplete sequence. */
71 	    if (unconvlenp != NULL)
72 		*unconvlenp = todo;
73 	    break;
74 	}
75 
76 	ch = utf_ptr2char(p);
77 	if (ch >= 0x10000)
78 	{
79 	    /* non-BMP character, encoding with surrogate pairs */
80 	    ++outlen;
81 	    if (outstr != NULL)
82 	    {
83 		*outstr++ = (0xD800 - (0x10000 >> 10)) + (ch >> 10);
84 		*outstr++ = 0xDC00 | (ch & 0x3FF);
85 	    }
86 	}
87 	else if (outstr != NULL)
88 	    *outstr++ = ch;
89 	++outlen;
90 	p += l;
91 	todo -= l;
92     }
93 
94     return outlen;
95 }
96 
97 /*
98  * Convert an UTF-16 string to UTF-8.
99  * The input is "instr[inlen]" with "inlen" in number of UTF-16 words.
100  * When "outstr" is NULL only return the required number of bytes.
101  * Otherwise "outstr" must be a buffer of sufficient size.
102  * Return the number of bytes produced.
103  */
104     int
105 utf16_to_utf8(short_u *instr, int inlen, char_u *outstr)
106 {
107     int		outlen = 0;
108     int		todo = inlen;
109     short_u	*p = instr;
110     int		l;
111     int		ch, ch2;
112 
113     while (todo > 0)
114     {
115 	ch = *p;
116 	if (ch >= 0xD800 && ch <= 0xDBFF && todo > 1)
117 	{
118 	    /* surrogate pairs handling */
119 	    ch2 = p[1];
120 	    if (ch2 >= 0xDC00 && ch2 <= 0xDFFF)
121 	    {
122 		ch = ((ch - 0xD800) << 10) + (ch2 & 0x3FF) + 0x10000;
123 		++p;
124 		--todo;
125 	    }
126 	}
127 	if (outstr != NULL)
128 	{
129 	    l = utf_char2bytes(ch, outstr);
130 	    outstr += l;
131 	}
132 	else
133 	    l = utf_char2len(ch);
134 	++p;
135 	outlen += l;
136 	--todo;
137     }
138 
139     return outlen;
140 }
141 
142 /*
143  * Call MultiByteToWideChar() and allocate memory for the result.
144  * Returns the result in "*out[*outlen]" with an extra zero appended.
145  * "outlen" is in words.
146  */
147     void
148 MultiByteToWideChar_alloc(UINT cp, DWORD flags,
149 	LPCSTR in, int inlen,
150 	LPWSTR *out, int *outlen)
151 {
152     *outlen = MultiByteToWideChar(cp, flags, in, inlen, 0, 0);
153     /* Add one one word to avoid a zero-length alloc(). */
154     *out = (LPWSTR)alloc(sizeof(WCHAR) * (*outlen + 1));
155     if (*out != NULL)
156     {
157 	MultiByteToWideChar(cp, flags, in, inlen, *out, *outlen);
158 	(*out)[*outlen] = 0;
159     }
160 }
161 
162 /*
163  * Call WideCharToMultiByte() and allocate memory for the result.
164  * Returns the result in "*out[*outlen]" with an extra NUL appended.
165  */
166     void
167 WideCharToMultiByte_alloc(UINT cp, DWORD flags,
168 	LPCWSTR in, int inlen,
169 	LPSTR *out, int *outlen,
170 	LPCSTR def, LPBOOL useddef)
171 {
172     *outlen = WideCharToMultiByte(cp, flags, in, inlen, NULL, 0, def, useddef);
173     /* Add one one byte to avoid a zero-length alloc(). */
174     *out = (LPSTR)alloc((unsigned)*outlen + 1);
175     if (*out != NULL)
176     {
177 	WideCharToMultiByte(cp, flags, in, inlen, *out, *outlen, def, useddef);
178 	(*out)[*outlen] = 0;
179     }
180 }
181 
182 #endif /* FEAT_MBYTE */
183 
184 #ifdef FEAT_CLIPBOARD
185 /*
186  * Clipboard stuff, for cutting and pasting text to other windows.
187  */
188 
189     void
190 win_clip_init(void)
191 {
192     clip_init(TRUE);
193 
194     /*
195      * Vim's own clipboard format recognises whether the text is char, line,
196      * or rectangular block.  Only useful for copying between two Vims.
197      * "VimClipboard" was used for previous versions, using the first
198      * character to specify MCHAR, MLINE or MBLOCK.
199      */
200     clip_star.format = RegisterClipboardFormat("VimClipboard2");
201     clip_star.format_raw = RegisterClipboardFormat("VimRawBytes");
202 }
203 
204 /* Type used for the clipboard type of Vim's data. */
205 typedef struct
206 {
207     int type;		/* MCHAR, MBLOCK or MLINE */
208     int txtlen;		/* length of CF_TEXT in bytes */
209     int ucslen;		/* length of CF_UNICODETEXT in words */
210     int rawlen;		/* length of clip_star.format_raw, including encoding,
211 			   excluding terminating NUL */
212 } VimClipType_t;
213 
214 /*
215  * Make vim the owner of the current selection.  Return OK upon success.
216  */
217     int
218 clip_mch_own_selection(VimClipboard *cbd UNUSED)
219 {
220     /*
221      * Never actually own the clipboard.  If another application sets the
222      * clipboard, we don't want to think that we still own it.
223      */
224     return FAIL;
225 }
226 
227 /*
228  * Make vim NOT the owner of the current selection.
229  */
230     void
231 clip_mch_lose_selection(VimClipboard *cbd UNUSED)
232 {
233     /* Nothing needs to be done here */
234 }
235 
236 /*
237  * Copy "str[*size]" into allocated memory, changing CR-NL to NL.
238  * Return the allocated result and the size in "*size".
239  * Returns NULL when out of memory.
240  */
241     static char_u *
242 crnl_to_nl(const char_u *str, int *size)
243 {
244     int		pos = 0;
245     int		str_len = *size;
246     char_u	*ret;
247     char_u	*retp;
248 
249     /* Avoid allocating zero bytes, it generates an error message. */
250     ret = lalloc((long_u)(str_len == 0 ? 1 : str_len), TRUE);
251     if (ret != NULL)
252     {
253 	retp = ret;
254 	for (pos = 0; pos < str_len; ++pos)
255 	{
256 	    if (str[pos] == '\r' && str[pos + 1] == '\n')
257 	    {
258 		++pos;
259 		--(*size);
260 	    }
261 	    *retp++ = str[pos];
262 	}
263     }
264 
265     return ret;
266 }
267 
268 /*
269  * Wait for another process to Close the Clipboard.
270  * Returns TRUE for success.
271  */
272     static int
273 vim_open_clipboard(void)
274 {
275     int delay = 10;
276 
277     while (!OpenClipboard(NULL))
278     {
279 	if (delay > 500)
280 	    return FALSE;  /* waited too long, give up */
281 	Sleep(delay);
282 	delay *= 2;	/* wait for 10, 20, 40, 80, etc. msec */
283     }
284     return TRUE;
285 }
286 
287 /*
288  * Get the current selection and put it in the clipboard register.
289  *
290  * NOTE: Must use GlobalLock/Unlock here to ensure Win32s compatibility.
291  * On NT/W95 the clipboard data is a fixed global memory object and
292  * so its handle = its pointer.
293  * On Win32s, however, co-operation with the Win16 system means that
294  * the clipboard data is moveable and its handle is not a pointer at all,
295  * so we can't just cast the return value of GetClipboardData to (char_u*).
296  * <VN>
297  */
298     void
299 clip_mch_request_selection(VimClipboard *cbd)
300 {
301     VimClipType_t	metadata = { -1, -1, -1, -1 };
302     HGLOBAL		hMem = NULL;
303     char_u		*str = NULL;
304 #if defined(FEAT_MBYTE) && defined(WIN3264)
305     char_u		*to_free = NULL;
306 #endif
307 #ifdef FEAT_MBYTE
308     HGLOBAL		rawh = NULL;
309 #endif
310     int			str_size = 0;
311     int			maxlen;
312     size_t		n;
313 
314     /*
315      * Don't pass GetActiveWindow() as an argument to OpenClipboard() because
316      * then we can't paste back into the same window for some reason - webb.
317      */
318     if (!vim_open_clipboard())
319 	return;
320 
321     /* Check for vim's own clipboard format first.  This only gets the type of
322      * the data, still need to use CF_UNICODETEXT or CF_TEXT for the text. */
323     if (IsClipboardFormatAvailable(cbd->format))
324     {
325 	VimClipType_t	*meta_p;
326 	HGLOBAL		meta_h;
327 
328 	/* We have metadata on the clipboard; try to get it. */
329 	if ((meta_h = GetClipboardData(cbd->format)) != NULL
330 		&& (meta_p = (VimClipType_t *)GlobalLock(meta_h)) != NULL)
331 	{
332 	    /* The size of "VimClipType_t" changed, "rawlen" was added later.
333 	     * Only copy what is available for backwards compatibility. */
334 	    n = sizeof(VimClipType_t);
335 	    if (GlobalSize(meta_h) < n)
336 		n = GlobalSize(meta_h);
337 	    memcpy(&metadata, meta_p, n);
338 	    GlobalUnlock(meta_h);
339 	}
340     }
341 
342 #ifdef FEAT_MBYTE
343     /* Check for Vim's raw clipboard format first.  This is used without
344      * conversion, but only if 'encoding' matches. */
345     if (IsClipboardFormatAvailable(cbd->format_raw)
346 				      && metadata.rawlen > (int)STRLEN(p_enc))
347     {
348 	/* We have raw data on the clipboard; try to get it. */
349 	if ((rawh = GetClipboardData(cbd->format_raw)) != NULL)
350 	{
351 	    char_u	*rawp;
352 
353 	    rawp = (char_u *)GlobalLock(rawh);
354 	    if (rawp != NULL && STRCMP(p_enc, rawp) == 0)
355 	    {
356 		n = STRLEN(p_enc) + 1;
357 		str = rawp + n;
358 		str_size = (int)(metadata.rawlen - n);
359 	    }
360 	    else
361 	    {
362 		GlobalUnlock(rawh);
363 		rawh = NULL;
364 	    }
365 	}
366     }
367     if (str == NULL)
368     {
369 #endif
370 
371 #if defined(FEAT_MBYTE) && defined(WIN3264)
372     /* Try to get the clipboard in Unicode if it's not an empty string. */
373     if (IsClipboardFormatAvailable(CF_UNICODETEXT) && metadata.ucslen != 0)
374     {
375 	HGLOBAL hMemW;
376 
377 	if ((hMemW = GetClipboardData(CF_UNICODETEXT)) != NULL)
378 	{
379 	    WCHAR *hMemWstr = (WCHAR *)GlobalLock(hMemW);
380 
381 	    /* Use the length of our metadata if possible, but limit it to the
382 	     * GlobalSize() for safety. */
383 	    maxlen = (int)(GlobalSize(hMemW) / sizeof(WCHAR));
384 	    if (metadata.ucslen >= 0)
385 	    {
386 		if (metadata.ucslen > maxlen)
387 		    str_size = maxlen;
388 		else
389 		    str_size = metadata.ucslen;
390 	    }
391 	    else
392 	    {
393 		for (str_size = 0; str_size < maxlen; ++str_size)
394 		    if (hMemWstr[str_size] == NUL)
395 			break;
396 	    }
397 	    to_free = str = utf16_to_enc((short_u *)hMemWstr, &str_size);
398 	    GlobalUnlock(hMemW);
399 	}
400     }
401     else
402 #endif
403     /* Get the clipboard in the Active codepage. */
404     if (IsClipboardFormatAvailable(CF_TEXT))
405     {
406 	if ((hMem = GetClipboardData(CF_TEXT)) != NULL)
407 	{
408 	    str = (char_u *)GlobalLock(hMem);
409 
410 	    /* The length is either what our metadata says or the strlen().
411 	     * But limit it to the GlobalSize() for safety. */
412 	    maxlen = (int)GlobalSize(hMem);
413 	    if (metadata.txtlen >= 0)
414 	    {
415 		if (metadata.txtlen > maxlen)
416 		    str_size = maxlen;
417 		else
418 		    str_size = metadata.txtlen;
419 	    }
420 	    else
421 	    {
422 		for (str_size = 0; str_size < maxlen; ++str_size)
423 		    if (str[str_size] == NUL)
424 			break;
425 	    }
426 
427 # if defined(FEAT_MBYTE) && defined(WIN3264)
428 	    /* The text is in the active codepage.  Convert to 'encoding',
429 	     * going through UTF-16. */
430 	    acp_to_enc(str, str_size, &to_free, &maxlen);
431 	    if (to_free != NULL)
432 	    {
433 		str_size = maxlen;
434 		str = to_free;
435 	    }
436 # endif
437 	}
438     }
439 #ifdef FEAT_MBYTE
440     }
441 #endif
442 
443     if (str != NULL && *str != NUL)
444     {
445 	char_u *temp_clipboard;
446 
447 	/* If the type is not known detect it. */
448 	if (metadata.type == -1)
449 	    metadata.type = MAUTO;
450 
451 	/* Translate <CR><NL> into <NL>. */
452 	temp_clipboard = crnl_to_nl(str, &str_size);
453 	if (temp_clipboard != NULL)
454 	{
455 	    clip_yank_selection(metadata.type, temp_clipboard, str_size, cbd);
456 	    vim_free(temp_clipboard);
457 	}
458     }
459 
460     /* unlock the global object */
461     if (hMem != NULL)
462 	GlobalUnlock(hMem);
463 #ifdef FEAT_MBYTE
464     if (rawh != NULL)
465 	GlobalUnlock(rawh);
466 #endif
467     CloseClipboard();
468 #if defined(FEAT_MBYTE) && defined(WIN3264)
469     vim_free(to_free);
470 #endif
471 }
472 
473 /*
474  * Send the current selection to the clipboard.
475  */
476     void
477 clip_mch_set_selection(VimClipboard *cbd)
478 {
479     char_u		*str = NULL;
480     VimClipType_t	metadata;
481     long_u		txtlen;
482     HGLOBAL		hMemRaw = NULL;
483     HGLOBAL		hMem = NULL;
484     HGLOBAL		hMemVim = NULL;
485 # if defined(FEAT_MBYTE) && defined(WIN3264)
486     HGLOBAL		hMemW = NULL;
487 # endif
488 
489     /* If the '*' register isn't already filled in, fill it in now */
490     cbd->owned = TRUE;
491     clip_get_selection(cbd);
492     cbd->owned = FALSE;
493 
494     /* Get the text to be put on the clipboard, with CR-LF. */
495     metadata.type = clip_convert_selection(&str, &txtlen, cbd);
496     if (metadata.type < 0)
497 	return;
498     metadata.txtlen = (int)txtlen;
499     metadata.ucslen = 0;
500     metadata.rawlen = 0;
501 
502 #ifdef FEAT_MBYTE
503     /* Always set the raw bytes: 'encoding', NUL and the text.  This is used
504      * when copy/paste from/to Vim with the same 'encoding', so that illegal
505      * bytes can also be copied and no conversion is needed. */
506     {
507 	LPSTR lpszMemRaw;
508 
509 	metadata.rawlen = (int)(txtlen + STRLEN(p_enc) + 1);
510 	hMemRaw = (LPSTR)GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE,
511 							 metadata.rawlen + 1);
512 	lpszMemRaw = (LPSTR)GlobalLock(hMemRaw);
513 	if (lpszMemRaw != NULL)
514 	{
515 	    STRCPY(lpszMemRaw, p_enc);
516 	    memcpy(lpszMemRaw + STRLEN(p_enc) + 1, str, txtlen + 1);
517 	    GlobalUnlock(hMemRaw);
518 	}
519 	else
520 	    metadata.rawlen = 0;
521     }
522 #endif
523 
524 # if defined(FEAT_MBYTE) && defined(WIN3264)
525     {
526 	WCHAR		*out;
527 	int		len = metadata.txtlen;
528 
529 	/* Convert the text to UTF-16. This is put on the clipboard as
530 	 * CF_UNICODETEXT. */
531 	out = (WCHAR *)enc_to_utf16(str, &len);
532 	if (out != NULL)
533 	{
534 	    WCHAR *lpszMemW;
535 
536 	    /* Convert the text for CF_TEXT to Active codepage. Otherwise it's
537 	     * p_enc, which has no relation to the Active codepage. */
538 	    metadata.txtlen = WideCharToMultiByte(GetACP(), 0, out, len,
539 							       NULL, 0, 0, 0);
540 	    vim_free(str);
541 	    str = (char_u *)alloc((unsigned)(metadata.txtlen == 0 ? 1
542 							  : metadata.txtlen));
543 	    if (str == NULL)
544 	    {
545 		vim_free(out);
546 		return;		/* out of memory */
547 	    }
548 	    WideCharToMultiByte(GetACP(), 0, out, len,
549 					   (LPSTR)str, metadata.txtlen, 0, 0);
550 
551 	    /* Allocate memory for the UTF-16 text, add one NUL word to
552 	     * terminate the string. */
553 	    hMemW = (LPSTR)GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE,
554 						   (len + 1) * sizeof(WCHAR));
555 	    lpszMemW = (WCHAR *)GlobalLock(hMemW);
556 	    if (lpszMemW != NULL)
557 	    {
558 		memcpy(lpszMemW, out, len * sizeof(WCHAR));
559 		lpszMemW[len] = NUL;
560 		GlobalUnlock(hMemW);
561 	    }
562 	    vim_free(out);
563 	    metadata.ucslen = len;
564 	}
565     }
566 # endif
567 
568     /* Allocate memory for the text, add one NUL byte to terminate the string.
569      */
570     hMem = GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE, metadata.txtlen + 1);
571     {
572 	LPSTR lpszMem = (LPSTR)GlobalLock(hMem);
573 
574 	if (lpszMem)
575 	{
576 	    vim_strncpy((char_u *)lpszMem, str, metadata.txtlen);
577 	    GlobalUnlock(hMem);
578 	}
579     }
580 
581     /* Set up metadata: */
582     {
583 	VimClipType_t *lpszMemVim = NULL;
584 
585 	hMemVim = GlobalAlloc(GMEM_MOVEABLE|GMEM_DDESHARE,
586 						       sizeof(VimClipType_t));
587 	lpszMemVim = (VimClipType_t *)GlobalLock(hMemVim);
588 	memcpy(lpszMemVim, &metadata, sizeof(metadata));
589 	GlobalUnlock(hMemVim);
590     }
591 
592     /*
593      * Open the clipboard, clear it and put our text on it.
594      * Always set our Vim format.  Put Unicode and plain text on it.
595      *
596      * Don't pass GetActiveWindow() as an argument to OpenClipboard()
597      * because then we can't paste back into the same window for some
598      * reason - webb.
599      */
600     if (vim_open_clipboard())
601     {
602 	if (EmptyClipboard())
603 	{
604 	    SetClipboardData(cbd->format, hMemVim);
605 	    hMemVim = 0;
606 # if defined(FEAT_MBYTE) && defined(WIN3264)
607 	    if (hMemW != NULL)
608 	    {
609 		if (SetClipboardData(CF_UNICODETEXT, hMemW) != NULL)
610 		    hMemW = NULL;
611 	    }
612 # endif
613 	    /* Always use CF_TEXT.  On Win98 Notepad won't obtain the
614 	     * CF_UNICODETEXT text, only CF_TEXT. */
615 	    SetClipboardData(CF_TEXT, hMem);
616 	    hMem = 0;
617 	}
618 	CloseClipboard();
619     }
620 
621     vim_free(str);
622     /* Free any allocations we didn't give to the clipboard: */
623     if (hMemRaw)
624 	GlobalFree(hMemRaw);
625     if (hMem)
626 	GlobalFree(hMem);
627 # if defined(FEAT_MBYTE) && defined(WIN3264)
628     if (hMemW)
629 	GlobalFree(hMemW);
630 # endif
631     if (hMemVim)
632 	GlobalFree(hMemVim);
633 }
634 
635 #endif /* FEAT_CLIPBOARD */
636 
637 #if defined(FEAT_MBYTE) || defined(PROTO)
638 /*
639  * Note: the following two functions are only guaranteed to work when using
640  * valid MS-Windows codepages or when iconv() is available.
641  */
642 
643 /*
644  * Convert "str" from 'encoding' to UTF-16.
645  * Input in "str" with length "*lenp".  When "lenp" is NULL, use strlen().
646  * Output is returned as an allocated string.  "*lenp" is set to the length of
647  * the result.  A trailing NUL is always added.
648  * Returns NULL when out of memory.
649  */
650     short_u *
651 enc_to_utf16(char_u *str, int *lenp)
652 {
653     vimconv_T	conv;
654     WCHAR	*ret;
655     char_u	*allocbuf = NULL;
656     int		len_loc;
657     int		length;
658 
659     if (lenp == NULL)
660     {
661 	len_loc = (int)STRLEN(str) + 1;
662 	lenp = &len_loc;
663     }
664 
665     if (enc_codepage > 0)
666     {
667 	/* We can do any CP### -> UTF-16 in one pass, and we can do it
668 	 * without iconv() (convert_* may need iconv). */
669 	MultiByteToWideChar_alloc(enc_codepage, 0, (LPCSTR)str, *lenp,
670 							       &ret, &length);
671     }
672     else
673     {
674 	/* Use "latin1" by default, we might be called before we have p_enc
675 	 * set up.  Convert to utf-8 first, works better with iconv().  Does
676 	 * nothing if 'encoding' is "utf-8". */
677 	conv.vc_type = CONV_NONE;
678 	if (convert_setup(&conv, p_enc ? p_enc : (char_u *)"latin1",
679 						   (char_u *)"utf-8") == FAIL)
680 	    return NULL;
681 	if (conv.vc_type != CONV_NONE)
682 	{
683 	    str = allocbuf = string_convert(&conv, str, lenp);
684 	    if (str == NULL)
685 		return NULL;
686 	}
687 	convert_setup(&conv, NULL, NULL);
688 
689 	length = utf8_to_utf16(str, *lenp, NULL, NULL);
690 	ret = (WCHAR *)alloc((unsigned)((length + 1) * sizeof(WCHAR)));
691 	if (ret != NULL)
692 	{
693 	    utf8_to_utf16(str, *lenp, (short_u *)ret, NULL);
694 	    ret[length] = 0;
695 	}
696 
697 	vim_free(allocbuf);
698     }
699 
700     *lenp = length;
701     return (short_u *)ret;
702 }
703 
704 /*
705  * Convert an UTF-16 string to 'encoding'.
706  * Input in "str" with length (counted in wide characters) "*lenp".  When
707  * "lenp" is NULL, use wcslen().
708  * Output is returned as an allocated string.  If "*lenp" is not NULL it is
709  * set to the length of the result.
710  * Returns NULL when out of memory.
711  */
712     char_u *
713 utf16_to_enc(short_u *str, int *lenp)
714 {
715     vimconv_T	conv;
716     char_u	*utf8_str = NULL, *enc_str = NULL;
717     int		len_loc;
718 
719     if (lenp == NULL)
720     {
721 	len_loc = (int)wcslen(str) + 1;
722 	lenp = &len_loc;
723     }
724 
725     if (enc_codepage > 0)
726     {
727 	/* We can do any UTF-16 -> CP### in one pass. */
728 	int length;
729 
730 	WideCharToMultiByte_alloc(enc_codepage, 0, str, *lenp,
731 					    (LPSTR *)&enc_str, &length, 0, 0);
732 	*lenp = length;
733 	return enc_str;
734     }
735 
736     /* Avoid allocating zero bytes, it generates an error message. */
737     utf8_str = alloc(utf16_to_utf8(str, *lenp == 0 ? 1 : *lenp, NULL));
738     if (utf8_str != NULL)
739     {
740 	*lenp = utf16_to_utf8(str, *lenp, utf8_str);
741 
742 	/* We might be called before we have p_enc set up. */
743 	conv.vc_type = CONV_NONE;
744 	convert_setup(&conv, (char_u *)"utf-8",
745 					    p_enc? p_enc: (char_u *)"latin1");
746 	if (conv.vc_type == CONV_NONE)
747 	{
748 	    /* p_enc is utf-8, so we're done. */
749 	    enc_str = utf8_str;
750 	}
751 	else
752 	{
753 	    enc_str = string_convert(&conv, utf8_str, lenp);
754 	    vim_free(utf8_str);
755 	}
756 
757 	convert_setup(&conv, NULL, NULL);
758     }
759 
760     return enc_str;
761 }
762 #endif /* FEAT_MBYTE */
763 
764 #if (defined(FEAT_MBYTE) && defined(WIN3264)) || defined(PROTO)
765 /*
766  * Convert from the active codepage to 'encoding'.
767  * Input is "str[str_size]".
768  * The result is in allocated memory: "out[outlen]".  With terminating NUL.
769  */
770     void
771 acp_to_enc(
772     char_u	*str,
773     int		str_size,
774     char_u	**out,
775     int		*outlen)
776 
777 {
778     LPWSTR	widestr;
779 
780     MultiByteToWideChar_alloc(GetACP(), 0, (LPCSTR)str, str_size,
781 							    &widestr, outlen);
782     if (widestr != NULL)
783     {
784 	++*outlen;	/* Include the 0 after the string */
785 	*out = utf16_to_enc((short_u *)widestr, outlen);
786 	vim_free(widestr);
787     }
788 }
789 
790 /*
791  * Convert from 'encoding' to the active codepage.
792  * Input is "str[str_size]".
793  * The result is in allocated memory: "out[outlen]".  With terminating NUL.
794  */
795     void
796 enc_to_acp(
797     char_u	*str,
798     int		str_size,
799     char_u	**out,
800     int		*outlen)
801 
802 {
803     LPWSTR	widestr;
804     int		len = str_size;
805 
806     widestr = (WCHAR *)enc_to_utf16(str, &len);
807     if (widestr != NULL)
808     {
809 	WideCharToMultiByte_alloc(GetACP(), 0, widestr, len,
810 						(LPSTR *)out, outlen, 0, 0);
811 	vim_free(widestr);
812     }
813 }
814 #endif
815