xref: /haiku/src/libs/iconv/loop_wchar.h (revision 58481f0f6ef1a61ba07283f012cafbc2ed874ead)
1 /*
2  * Copyright (C) 2000-2002, 2005-2006 Free Software Foundation, Inc.
3  * This file is part of the GNU LIBICONV Library.
4  *
5  * The GNU LIBICONV Library is free software; you can redistribute it
6  * and/or modify it under the terms of the GNU Library General Public
7  * License as published by the Free Software Foundation; either version 2
8  * of the License, or (at your option) any later version.
9  *
10  * The GNU LIBICONV Library is distributed in the hope that it will be
11  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Library General Public License for more details.
14  *
15  * You should have received a copy of the GNU Library General Public
16  * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
17  * If not, write to the Free Software Foundation, Inc., 51 Franklin Street,
18  * Fifth Floor, Boston, MA 02110-1301, USA.
19  */
20 
21 /* This file defines three conversion loops:
22      - from wchar_t to anything else,
23      - from anything else to wchar_t,
24      - from wchar_t to wchar_t.
25  */
26 
27 #if HAVE_WCRTOMB || HAVE_MBRTOWC
28 # include <wchar.h>
29 # define BUF_SIZE 64  /* assume MB_LEN_MAX <= 64 */
30   /* Some systems, like BeOS, have multibyte encodings but lack mbstate_t.  */
31   extern size_t mbrtowc ();
32 # ifdef mbstate_t
33 #  define mbrtowc(pwc, s, n, ps) (mbrtowc)(pwc, s, n, 0)
34 #  define mbsinit(ps) 1
35 # endif
36 # ifndef mbsinit
37 #  if !HAVE_MBSINIT
38 #   define mbsinit(ps) 1
39 #  endif
40 # endif
41 #else
42 # ifndef mbstate_t
43    typedef int mbstate_t;
44 # endif
45 #endif
46 
47 /*
48  * The first two conversion loops have an extended conversion descriptor.
49  */
50 struct wchar_conv_struct {
51   struct conv_struct parent;
52   mbstate_t state;
53 };
54 
55 
56 #if HAVE_WCRTOMB
57 
58 /* From wchar_t to anything else. */
59 
60 #ifndef LIBICONV_PLUG
61 
62 #if 0
63 
64 struct wc_to_mb_fallback_locals {
65   struct wchar_conv_struct * l_wcd;
66   char* l_outbuf;
67   size_t l_outbytesleft;
68   int l_errno;
69 };
70 
71 /* A callback that writes a string given in the locale encoding. */
72 static void wc_to_mb_write_replacement (const char *buf, size_t buflen,
73                                         void* callback_arg)
74 {
75   struct wc_to_mb_fallback_locals * plocals =
76     (struct wc_to_mb_fallback_locals *) callback_arg;
77   /* Do nothing if already encountered an error in a previous call. */
78   if (plocals->l_errno == 0) {
79     /* Attempt to convert the passed buffer to the target encoding.
80        Here we don't support characters split across multiple calls. */
81     const char* bufptr = buf;
82     size_t bufleft = buflen;
83     size_t res = unicode_loop_convert(&plocals->l_wcd->parent,
84                                       &bufptr,&bufleft,
85                                       &plocals->l_outbuf,&plocals->l_outbytesleft);
86     if (res == (size_t)(-1)) {
87       if (errno == EILSEQ || errno == EINVAL)
88         /* Invalid buf contents. */
89         plocals->l_errno = EILSEQ;
90       else if (errno == E2BIG)
91         /* Output buffer too small. */
92         plocals->l_errno = E2BIG;
93       else
94         abort();
95     } else {
96       /* Successful conversion. */
97       if (bufleft > 0)
98         abort();
99     }
100   }
101 }
102 
103 #else
104 
105 struct wc_to_mb_fallback_locals {
106   char* l_outbuf;
107   size_t l_outbytesleft;
108   int l_errno;
109 };
110 
111 /* A callback that writes a string given in the target encoding. */
112 static void wc_to_mb_write_replacement (const char *buf, size_t buflen,
113                                         void* callback_arg)
114 {
115   struct wc_to_mb_fallback_locals * plocals =
116     (struct wc_to_mb_fallback_locals *) callback_arg;
117   /* Do nothing if already encountered an error in a previous call. */
118   if (plocals->l_errno == 0) {
119     /* Attempt to copy the passed buffer to the output buffer. */
120     if (plocals->l_outbytesleft < buflen)
121       plocals->l_errno = E2BIG;
122     else {
123       memcpy(plocals->l_outbuf, buf, buflen);
124       plocals->l_outbuf += buflen;
125       plocals->l_outbytesleft -= buflen;
126     }
127   }
128 }
129 
130 #endif
131 
132 #endif /* !LIBICONV_PLUG */
133 
134 static size_t wchar_from_loop_convert (iconv_t icd,
135                                        const char* * inbuf, size_t *inbytesleft,
136                                        char* * outbuf, size_t *outbytesleft)
137 {
138   struct wchar_conv_struct * wcd = (struct wchar_conv_struct *) icd;
139   size_t result = 0;
140   while (*inbytesleft >= sizeof(wchar_t)) {
141     const wchar_t * inptr = (const wchar_t *) *inbuf;
142     size_t inleft = *inbytesleft;
143     char buf[BUF_SIZE];
144     mbstate_t state = wcd->state;
145     size_t bufcount = 0;
146     while (inleft >= sizeof(wchar_t)) {
147       /* Convert one wchar_t to multibyte representation. */
148       size_t count = wcrtomb(buf+bufcount,*inptr,&state);
149       if (count == (size_t)(-1)) {
150         /* Invalid input. */
151         if (wcd->parent.discard_ilseq) {
152           count = 0;
153         }
154         #ifndef LIBICONV_PLUG
155         else if (wcd->parent.fallbacks.wc_to_mb_fallback != NULL) {
156           /* Drop the contents of buf[] accumulated so far, and instead
157              pass all queued wide characters to the fallback handler. */
158           struct wc_to_mb_fallback_locals locals;
159           const wchar_t * fallback_inptr;
160           #if 0
161           locals.l_wcd = wcd;
162           #endif
163           locals.l_outbuf = *outbuf;
164           locals.l_outbytesleft = *outbytesleft;
165           locals.l_errno = 0;
166           for (fallback_inptr = (const wchar_t *) *inbuf;
167                fallback_inptr <= inptr;
168                fallback_inptr++)
169             wcd->parent.fallbacks.wc_to_mb_fallback(*fallback_inptr,
170                                                     wc_to_mb_write_replacement,
171                                                     &locals,
172                                                     wcd->parent.fallbacks.data);
173           if (locals.l_errno != 0) {
174             errno = locals.l_errno;
175             return -1;
176           }
177           wcd->state = state;
178           *inbuf = (const char *) (inptr + 1);
179           *inbytesleft = inleft - sizeof(wchar_t);
180           *outbuf = locals.l_outbuf;
181           *outbytesleft = locals.l_outbytesleft;
182           result += 1;
183           break;
184         }
185         #endif
186         else {
187           errno = EILSEQ;
188           return -1;
189         }
190       }
191       inptr++;
192       inleft -= sizeof(wchar_t);
193       bufcount += count;
194       if (count == 0) {
195         /* Continue, append next wchar_t. */
196       } else {
197         /* Attempt to convert the accumulated multibyte representations
198            to the target encoding. */
199         const char* bufptr = buf;
200         size_t bufleft = bufcount;
201         char* outptr = *outbuf;
202         size_t outleft = *outbytesleft;
203         size_t res = unicode_loop_convert(&wcd->parent,
204                                           &bufptr,&bufleft,
205                                           &outptr,&outleft);
206         if (res == (size_t)(-1)) {
207           if (errno == EILSEQ)
208             /* Invalid input. */
209             return -1;
210           else if (errno == E2BIG)
211             /* Output buffer too small. */
212             return -1;
213           else if (errno == EINVAL) {
214             /* Continue, append next wchar_t, but avoid buffer overrun. */
215             if (bufcount + MB_CUR_MAX > BUF_SIZE)
216               abort();
217           } else
218             abort();
219         } else {
220           /* Successful conversion. */
221           wcd->state = state;
222           *inbuf = (const char *) inptr;
223           *inbytesleft = inleft;
224           *outbuf = outptr;
225           *outbytesleft = outleft;
226           result += res;
227           break;
228         }
229       }
230     }
231   }
232   return result;
233 }
234 
235 static size_t wchar_from_loop_reset (iconv_t icd,
236                                      char* * outbuf, size_t *outbytesleft)
237 {
238   struct wchar_conv_struct * wcd = (struct wchar_conv_struct *) icd;
239   if (outbuf == NULL || *outbuf == NULL) {
240     /* Reset the states. */
241     memset(&wcd->state,'\0',sizeof(mbstate_t));
242     return unicode_loop_reset(&wcd->parent,NULL,NULL);
243   } else {
244     if (!mbsinit(&wcd->state)) {
245       mbstate_t state = wcd->state;
246       char buf[BUF_SIZE];
247       size_t bufcount = wcrtomb(buf,(wchar_t)0,&state);
248       if (bufcount == (size_t)(-1) || bufcount == 0 || buf[bufcount-1] != '\0')
249         abort();
250       else {
251         const char* bufptr = buf;
252         size_t bufleft = bufcount-1;
253         char* outptr = *outbuf;
254         size_t outleft = *outbytesleft;
255         size_t res = unicode_loop_convert(&wcd->parent,
256                                           &bufptr,&bufleft,
257                                           &outptr,&outleft);
258         if (res == (size_t)(-1)) {
259           if (errno == E2BIG)
260             return -1;
261           else
262             abort();
263         } else {
264           res = unicode_loop_reset(&wcd->parent,&outptr,&outleft);
265           if (res == (size_t)(-1))
266             return res;
267           else {
268             /* Successful. */
269             wcd->state = state;
270             *outbuf = outptr;
271             *outbytesleft = outleft;
272             return 0;
273           }
274         }
275       }
276     } else
277       return unicode_loop_reset(&wcd->parent,outbuf,outbytesleft);
278   }
279 }
280 
281 #endif
282 
283 
284 #if HAVE_MBRTOWC
285 
286 /* From anything else to wchar_t. */
287 
288 #ifndef LIBICONV_PLUG
289 
290 struct mb_to_wc_fallback_locals {
291   char* l_outbuf;
292   size_t l_outbytesleft;
293   int l_errno;
294 };
295 
296 static void mb_to_wc_write_replacement (const wchar_t *buf, size_t buflen,
297                                         void* callback_arg)
298 {
299   struct mb_to_wc_fallback_locals * plocals =
300     (struct mb_to_wc_fallback_locals *) callback_arg;
301   /* Do nothing if already encountered an error in a previous call. */
302   if (plocals->l_errno == 0) {
303     /* Attempt to copy the passed buffer to the output buffer. */
304     if (plocals->l_outbytesleft < sizeof(wchar_t)*buflen)
305       plocals->l_errno = E2BIG;
306     else {
307       for (; buflen > 0; buf++, buflen--) {
308         *(wchar_t*) plocals->l_outbuf = *buf;
309         plocals->l_outbuf += sizeof(wchar_t);
310         plocals->l_outbytesleft -= sizeof(wchar_t);
311       }
312     }
313   }
314 }
315 
316 #endif /* !LIBICONV_PLUG */
317 
318 static size_t wchar_to_loop_convert (iconv_t icd,
319                                      const char* * inbuf, size_t *inbytesleft,
320                                      char* * outbuf, size_t *outbytesleft)
321 {
322   struct wchar_conv_struct * wcd = (struct wchar_conv_struct *) icd;
323   size_t result = 0;
324   while (*inbytesleft > 0) {
325     size_t incount;
326     for (incount = 1; incount <= *inbytesleft; incount++) {
327       char buf[BUF_SIZE];
328       const char* inptr = *inbuf;
329       size_t inleft = incount;
330       char* bufptr = buf;
331       size_t bufleft = BUF_SIZE;
332       size_t res = unicode_loop_convert(&wcd->parent,
333                                         &inptr,&inleft,
334                                         &bufptr,&bufleft);
335       if (res == (size_t)(-1)) {
336         if (errno == EILSEQ)
337           /* Invalid input. */
338           return -1;
339         else if (errno == EINVAL) {
340           /* Incomplete input. Next try with one more input byte. */
341         } else
342           /* E2BIG shouldn't occur. */
343           abort();
344       } else {
345         /* Successful conversion. */
346         size_t bufcount = bufptr-buf; /* = BUF_SIZE-bufleft */
347         mbstate_t state = wcd->state;
348         wchar_t wc;
349         res = mbrtowc(&wc,buf,bufcount,&state);
350         if (res == (size_t)(-2)) {
351           /* Next try with one more input byte. */
352         } else {
353           if (res == (size_t)(-1)) {
354             /* Invalid input. */
355             if (wcd->parent.discard_ilseq) {
356             }
357             #ifndef LIBICONV_PLUG
358             else if (wcd->parent.fallbacks.mb_to_wc_fallback != NULL) {
359               /* Drop the contents of buf[] accumulated so far, and instead
360                  pass all queued chars to the fallback handler. */
361               struct mb_to_wc_fallback_locals locals;
362               locals.l_outbuf = *outbuf;
363               locals.l_outbytesleft = *outbytesleft;
364               locals.l_errno = 0;
365               wcd->parent.fallbacks.mb_to_wc_fallback(*inbuf, incount,
366                                                       mb_to_wc_write_replacement,
367                                                       &locals,
368                                                       wcd->parent.fallbacks.data);
369               if (locals.l_errno != 0) {
370                 errno = locals.l_errno;
371                 return -1;
372               }
373               /* Restoring the state is not needed because it is the initial
374                  state anyway: For all known locale encodings, the multibyte
375                  to wchar_t conversion doesn't have shift state, and we have
376                  excluded partial accumulated characters. */
377               /* wcd->state = state; */
378               *inbuf += incount;
379               *inbytesleft -= incount;
380               *outbuf = locals.l_outbuf;
381               *outbytesleft = locals.l_outbytesleft;
382               result += 1;
383               break;
384             }
385             #endif
386             else
387               return -1;
388           } else {
389             if (*outbytesleft < sizeof(wchar_t)) {
390               errno = E2BIG;
391               return -1;
392             }
393             *(wchar_t*) *outbuf = wc;
394             /* Restoring the state is not needed because it is the initial
395                state anyway: For all known locale encodings, the multibyte
396                to wchar_t conversion doesn't have shift state, and we have
397                excluded partial accumulated characters. */
398             /* wcd->state = state; */
399             *outbuf += sizeof(wchar_t);
400             *outbytesleft -= sizeof(wchar_t);
401           }
402           *inbuf += incount;
403           *inbytesleft -= incount;
404           result += res;
405           break;
406         }
407       }
408     }
409   }
410   return result;
411 }
412 
413 static size_t wchar_to_loop_reset (iconv_t icd,
414                                    char* * outbuf, size_t *outbytesleft)
415 {
416   struct wchar_conv_struct * wcd = (struct wchar_conv_struct *) icd;
417   size_t res = unicode_loop_reset(&wcd->parent,outbuf,outbytesleft);
418   if (res == (size_t)(-1))
419     return res;
420   memset(&wcd->state,0,sizeof(mbstate_t));
421   return 0;
422 }
423 
424 #endif
425 
426 
427 /* From wchar_t to wchar_t. */
428 
429 static size_t wchar_id_loop_convert (iconv_t icd,
430                                      const char* * inbuf, size_t *inbytesleft,
431                                      char* * outbuf, size_t *outbytesleft)
432 {
433   struct conv_struct * cd = (struct conv_struct *) icd;
434   const wchar_t* inptr = (const wchar_t*) *inbuf;
435   size_t inleft = *inbytesleft / sizeof(wchar_t);
436   wchar_t* outptr = (wchar_t*) *outbuf;
437   size_t outleft = *outbytesleft / sizeof(wchar_t);
438   size_t count = (inleft <= outleft ? inleft : outleft);
439   if (count > 0) {
440     *inbytesleft -= count * sizeof(wchar_t);
441     *outbytesleft -= count * sizeof(wchar_t);
442     do {
443       wchar_t wc = *inptr++;
444       *outptr++ = wc;
445       #ifndef LIBICONV_PLUG
446       if (cd->hooks.wc_hook)
447         (*cd->hooks.wc_hook)(wc, cd->hooks.data);
448       #endif
449     } while (--count > 0);
450     *inbuf = (const char*) inptr;
451     *outbuf = (char*) outptr;
452   }
453   return 0;
454 }
455 
456 static size_t wchar_id_loop_reset (iconv_t icd,
457                                    char* * outbuf, size_t *outbytesleft)
458 {
459   return 0;
460 }
461