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1 /*
2  * encoding.c
3  */
4
5 /*
6  * Copyright (C) 2012, 2013 Eric Biggers
7  *
8  * This file is part of wimlib, a library for working with WIM files.
9  *
10  * wimlib is free software; you can redistribute it and/or modify it under the
11  * terms of the GNU General Public License as published by the Free
12  * Software Foundation; either version 3 of the License, or (at your option)
13  * any later version.
14  *
15  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
16  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
17  * A PARTICULAR PURPOSE. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with wimlib; if not, see http://www.gnu.org/licenses/.
22  */
23
24 #ifdef HAVE_CONFIG_H
25 #  include "config.h"
26 #endif
27
28 #include "wimlib.h"
29 #include "wimlib/assert.h"
30 #include "wimlib/encoding.h"
31 #include "wimlib/endianness.h"
32 #include "wimlib/error.h"
33 #include "wimlib/list.h"
34 #include "wimlib/util.h"
35
36 #include <errno.h>
37 #include <iconv.h>
38 #include <pthread.h>
39 #include <stdlib.h>
40 #include <string.h>
41
42 #ifdef HAVE_ALLOCA_H
43 #  include <alloca.h>
44 #endif
45
46 bool wimlib_mbs_is_utf8 = !TCHAR_IS_UTF16LE;
47
48 /* List of iconv_t conversion descriptors for a specific character conversion.
49  * The idea is that it is not thread-safe to have just one conversion
50  * descriptor, but it also is inefficient to open a new conversion descriptor to
51  * convert every string.  Both these problems can be solved by maintaining a
52  * list of conversion descriptors; then, a thread can use an existing conversion
53  * descriptor if available. */
54 struct iconv_list_head {
55         const char *from_encoding;
56         const char *to_encoding;
57         struct list_head list;
58         pthread_mutex_t mutex;
59 };
60
61 struct iconv_node {
62         iconv_t cd;
63         struct list_head list;
64         struct iconv_list_head *head;
65 };
66
67 #define ICONV_LIST(name, from, to)                      \
68 struct iconv_list_head name = {                         \
69         .from_encoding = from,                          \
70         .to_encoding = to,                              \
71         .list = LIST_HEAD_INIT(name.list),              \
72         .mutex = PTHREAD_MUTEX_INITIALIZER,             \
73 }
74
75 static iconv_t *
76 get_iconv(struct iconv_list_head *head)
77 {
78         iconv_t cd;
79         iconv_t *cd_p;
80         struct iconv_node *i;
81
82         pthread_mutex_lock(&head->mutex);
83         if (list_empty(&head->list)) {
84                 cd = iconv_open(head->to_encoding, head->from_encoding);
85                 if (cd == (iconv_t)-1) {
86                         ERROR_WITH_ERRNO("Failed to open iconv from %s to %s",
87                                          head->from_encoding, head->to_encoding);
88                         cd_p = NULL;
89                 } else {
90                         i = MALLOC(sizeof(struct iconv_node));
91                         if (i) {
92                                 i->head = head;
93                                 i->cd = cd;
94                                 cd_p = &i->cd;
95                         } else {
96                                 iconv_close(cd);
97                                 cd_p = NULL;
98                         }
99                 }
100         } else {
101                 i = container_of(head->list.next, struct iconv_node, list);
102                 list_del(head->list.next);
103                 cd_p = &i->cd;
104         }
105         pthread_mutex_unlock(&head->mutex);
106         return cd_p;
107 }
108
109 static void
110 put_iconv(iconv_t *cd)
111 {
112         int errno_save = errno;
113         struct iconv_node *i = container_of(cd, struct iconv_node, cd);
114         struct iconv_list_head *head = i->head;
115
116         pthread_mutex_lock(&head->mutex);
117         list_add(&i->list, &head->list);
118         pthread_mutex_unlock(&head->mutex);
119         errno = errno_save;
120 }
121
122 /* Prevent printing an error message if a character conversion error occurs
123  * while printing an error message.  (This variable is not per-thread but it
124  * doesn't matter too much since it's just the error messages.) */
125 static bool error_message_being_printed = false;
126
127 #define DEFINE_CHAR_CONVERSION_FUNCTIONS(varname1, longname1, chartype1,\
128                                          varname2, longname2, chartype2,\
129                                          earlyreturn_on_utf8_locale,    \
130                                          earlyreturn_expr,              \
131                                          worst_case_len_expr,           \
132                                          err_return,                    \
133                                          err_msg,                       \
134                                          modifier)                      \
135 static ICONV_LIST(iconv_##varname1##_to_##varname2,                     \
136                   longname1, longname2);                                \
137                                                                         \
138 modifier int                                                            \
139 varname1##_to_##varname2##_nbytes(const chartype1 *in, size_t in_nbytes,\
140                                   size_t *out_nbytes_ret)               \
141 {                                                                       \
142         iconv_t *cd = get_iconv(&iconv_##varname1##_to_##varname2);     \
143         if (cd == NULL)                                                 \
144                 return WIMLIB_ERR_ICONV_NOT_AVAILABLE;                  \
145                                                                         \
146         chartype2 *buf;                                                 \
147         size_t bufsize;                                                 \
148         bool buf_onheap;                                                \
149         bufsize = (worst_case_len_expr) * sizeof(chartype2);            \
150         /* Worst case length */                                         \
151         if (bufsize <= STACK_MAX) {                                     \
152                 buf = alloca(bufsize);                                  \
153                 buf_onheap = false;                                     \
154         } else {                                                        \
155                 buf = MALLOC(bufsize);                                  \
156                 if (!buf)                                               \
157                         return WIMLIB_ERR_NOMEM;                        \
158                 buf_onheap = true;                                      \
159         }                                                               \
160                                                                         \
161         char *inbuf = (char*)in;                                        \
162         size_t inbytesleft = in_nbytes;                                 \
163         char *outbuf = (char*)buf;                                      \
164         size_t outbytesleft = bufsize;                                  \
165         size_t len;                                                     \
166         int ret;                                                        \
167                                                                         \
168         len = iconv(*cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft); \
169         if (len == (size_t)-1) {                                        \
170                 if (!error_message_being_printed) {                     \
171                         error_message_being_printed = true;             \
172                         err_msg;                                        \
173                         error_message_being_printed = false;            \
174                 }                                                       \
175                 ret = err_return;                                       \
176         } else {                                                        \
177                 *out_nbytes_ret = bufsize - outbytesleft;               \
178                 ret = 0;                                                \
179         }                                                               \
180         put_iconv(cd);                                                  \
181         if (buf_onheap)                                                 \
182                 FREE(buf);                                              \
183         return ret;                                                     \
184 }                                                                       \
185                                                                         \
186 modifier int                                                            \
187 varname1##_to_##varname2##_buf(const chartype1 *in, size_t in_nbytes,   \
188                                chartype2 *out)                          \
189 {                                                                       \
190         iconv_t *cd = get_iconv(&iconv_##varname1##_to_##varname2);     \
191         if (cd == NULL)                                                 \
192                 return WIMLIB_ERR_ICONV_NOT_AVAILABLE;                  \
193                                                                         \
194         char *inbuf = (char*)in;                                        \
195         size_t inbytesleft = in_nbytes;                                 \
196         char *outbuf = (char*)out;                                      \
197         const size_t LARGE_NUMBER = 1000000000;                         \
198         size_t outbytesleft = LARGE_NUMBER;                             \
199         size_t len;                                                     \
200         int ret;                                                        \
201                                                                         \
202         len = iconv(*cd, &inbuf, &inbytesleft, &outbuf, &outbytesleft); \
203         if (len == (size_t)-1) {                                        \
204                 if (!error_message_being_printed) {                     \
205                         error_message_being_printed = true;             \
206                         err_msg;                                        \
207                         error_message_being_printed = false;            \
208                 }                                                       \
209                 ret = err_return;                                       \
210         } else {                                                        \
211                 out[(LARGE_NUMBER-outbytesleft)/sizeof(chartype2)] = 0; \
212                 ret = 0;                                                \
213         }                                                               \
214         put_iconv(cd);                                                  \
215         return ret;                                                     \
216 }                                                                       \
217                                                                         \
218 modifier int                                                            \
219 varname1##_to_##varname2(const chartype1 *in, size_t in_nbytes,         \
220                          chartype2 **out_ret,                           \
221                          size_t *out_nbytes_ret)                        \
222 {                                                                       \
223         int ret;                                                        \
224         chartype2 *out;                                                 \
225         size_t out_nbytes;                                              \
226                                                                         \
227         if (earlyreturn_on_utf8_locale && wimlib_mbs_is_utf8) {         \
228                 earlyreturn_expr;                                       \
229                 /* Out same as in */                                    \
230                 out = MALLOC(in_nbytes + sizeof(chartype2));            \
231                 if (!out)                                               \
232                         return WIMLIB_ERR_NOMEM;                        \
233                 memcpy(out, in, in_nbytes);                             \
234                 out[in_nbytes / sizeof(chartype2)] = 0;                 \
235                 *out_ret = out;                                         \
236                 *out_nbytes_ret = in_nbytes;                            \
237                 return 0;                                               \
238         }                                                               \
239                                                                         \
240         ret = varname1##_to_##varname2##_nbytes(in, in_nbytes,          \
241                                                 &out_nbytes);           \
242         if (ret)                                                        \
243                 return ret;                                             \
244                                                                         \
245         out = MALLOC(out_nbytes + sizeof(chartype2));                   \
246         if (!out)                                                       \
247                 return WIMLIB_ERR_NOMEM;                                \
248                                                                         \
249         ret = varname1##_to_##varname2##_buf(in, in_nbytes, out);       \
250         if (ret) {                                                      \
251                 FREE(out);                                              \
252         } else {                                                        \
253                 *out_ret = out;                                         \
254                 *out_nbytes_ret = out_nbytes;                           \
255         }                                                               \
256         return ret;                                                     \
257 }
258
259 #if !TCHAR_IS_UTF16LE
260
261 /* UNIX */
262
263 DEFINE_CHAR_CONVERSION_FUNCTIONS(utf8, "UTF-8", tchar,
264                                  utf16le, "UTF-16LE", utf16lechar,
265                                  false,
266                                  ,
267                                  in_nbytes * 2,
268                                  WIMLIB_ERR_INVALID_UTF8_STRING,
269                                  ERROR_WITH_ERRNO("Failed to convert UTF-8 string "
270                                                   "to UTF-16LE string!"),
271                                  static)
272
273 DEFINE_CHAR_CONVERSION_FUNCTIONS(utf16le, "UTF-16LE", utf16lechar,
274                                  utf8, "UTF-8", tchar,
275                                  false,
276                                  ,
277                                  in_nbytes * 2,
278                                  WIMLIB_ERR_INVALID_UTF16_STRING,
279                                  ERROR_WITH_ERRNO("Failed to convert UTF-16LE string "
280                                                   "to UTF-8 string!"),
281                                  static)
282
283 DEFINE_CHAR_CONVERSION_FUNCTIONS(tstr, "", tchar,
284                                  utf16le, "UTF-16LE", utf16lechar,
285                                  true,
286                                  return utf8_to_utf16le(in, in_nbytes, out_ret, out_nbytes_ret),
287                                  in_nbytes * 2,
288                                  WIMLIB_ERR_INVALID_MULTIBYTE_STRING,
289                                  ERROR_WITH_ERRNO("Failed to convert multibyte "
290                                                   "string \"%"TS"\" to UTF-16LE string!", in);
291                                  ERROR("If the data you provided was UTF-8, please make sure "
292                                        "the character encoding\n"
293                                        "        of your current locale is UTF-8."),
294                                  )
295
296 DEFINE_CHAR_CONVERSION_FUNCTIONS(utf16le, "UTF-16LE", utf16lechar,
297                                  tstr, "", tchar,
298                                  true,
299                                  return utf16le_to_utf8(in, in_nbytes, out_ret, out_nbytes_ret),
300                                  in_nbytes * 2,
301                                  WIMLIB_ERR_UNICODE_STRING_NOT_REPRESENTABLE,
302                                  ERROR("Failed to convert UTF-16LE string to "
303                                        "multibyte string!");
304                                  ERROR("This may be because the UTF-16LE string "
305                                        "could not be represented\n"
306                                        "        in your locale's character encoding."),
307                                  )
308 #endif
309
310 /* tchar to UTF-8 and back */
311 #if TCHAR_IS_UTF16LE
312
313 /* Windows */
314 DEFINE_CHAR_CONVERSION_FUNCTIONS(tstr, "UTF-16LE", tchar,
315                                  utf8, "UTF-8", char,
316                                  false,
317                                  ,
318                                  in_nbytes * 2,
319                                  WIMLIB_ERR_INVALID_UTF16_STRING,
320                                  ERROR_WITH_ERRNO("Failed to convert UTF-16LE "
321                                                   "string \"%"TS"\" to UTF-8 string!", in),
322                                  )
323
324 DEFINE_CHAR_CONVERSION_FUNCTIONS(utf8, "UTF-8", char,
325                                  tstr, "UTF-16LE", tchar,
326                                  false,
327                                  ,
328                                  in_nbytes * 2,
329                                  WIMLIB_ERR_INVALID_UTF8_STRING,
330                                  ERROR_WITH_ERRNO("Failed to convert UTF-8 string "
331                                                   "to UTF-16LE string!"),
332                                  )
333 #else
334
335 /* UNIX */
336
337 DEFINE_CHAR_CONVERSION_FUNCTIONS(tstr, "", tchar,
338                                  utf8, "UTF-8", char,
339                                  true,
340                                  ,
341                                  in_nbytes * 4,
342                                  WIMLIB_ERR_INVALID_MULTIBYTE_STRING,
343                                  ERROR_WITH_ERRNO("Failed to convert multibyte "
344                                                   "string \"%"TS"\" to UTF-8 string!", in);
345                                  ERROR("If the data you provided was UTF-8, please make sure "
346                                        "the character\n"
347                                        "        encoding of your current locale is UTF-8."),
348                                  )
349
350 DEFINE_CHAR_CONVERSION_FUNCTIONS(utf8, "UTF-8", char,
351                                  tstr, "", tchar,
352                                  true,
353                                  ,
354                                  in_nbytes * 4,
355                                  WIMLIB_ERR_UNICODE_STRING_NOT_REPRESENTABLE,
356                                  ERROR("Failed to convert UTF-8 string to "
357                                        "multibyte string!");
358                                  ERROR("This may be because the UTF-8 data "
359                                        "could not be represented\n"
360                                        "        in your locale's character encoding."),
361                                  )
362 #endif
363
364 int
365 tstr_to_utf8_simple(const tchar *tstr, char **out)
366 {
367         size_t out_nbytes;
368         return tstr_to_utf8(tstr, tstrlen(tstr) * sizeof(tchar),
369                             out, &out_nbytes);
370 }
371
372 int
373 utf8_to_tstr_simple(const char *utf8str, tchar **out)
374 {
375         size_t out_nbytes;
376         return utf8_to_tstr(utf8str, strlen(utf8str), out, &out_nbytes);
377 }
378
379 static void
380 iconv_cleanup(struct iconv_list_head *head)
381 {
382         pthread_mutex_destroy(&head->mutex);
383         while (!list_empty(&head->list)) {
384                 struct iconv_node *i;
385
386                 i = container_of(head->list.next, struct iconv_node, list);
387                 list_del(&i->list);
388                 iconv_close(i->cd);
389                 FREE(i);
390         }
391 }
392
393 void
394 iconv_global_cleanup(void)
395 {
396         iconv_cleanup(&iconv_utf8_to_tstr);
397         iconv_cleanup(&iconv_tstr_to_utf8);
398 #if !TCHAR_IS_UTF16LE
399         iconv_cleanup(&iconv_utf16le_to_tstr);
400         iconv_cleanup(&iconv_tstr_to_utf16le);
401         iconv_cleanup(&iconv_utf16le_to_utf8);
402         iconv_cleanup(&iconv_utf8_to_utf16le);
403 #endif
404 }
405
406 /* A table that maps from UCS-2 characters to their upper case equivalents.
407  * Index and array values are both CPU endian.
408  * Note: this is only an *approximation* of real UTF-16 case folding.
409  */
410 static u16 upcase[65536];
411
412 /*
413  * Initialize the 'upcase' table.
414  *
415  * Code modified from NTFS-3g, original copyright notices below:
416  *
417  * Copyright (c) 2000-2004 Anton Altaparmakov
418  * Copyright (c) 2002-2009 Szabolcs Szakacsits
419  * Copyright (c) 2008-2011 Jean-Pierre Andre
420  * Copyright (c) 2008      Bernhard Kaindl
421  *
422  * License GPLv2 or later.
423  *
424  * The expanded table itself is the same as that used by Windows Vista for
425  * NTFS case insensitivity.
426  */
427 void
428 init_upcase(void)
429 {
430         /*
431          *      This is the table as defined by Vista
432          */
433         /*
434          * "Start" is inclusive and "End" is exclusive, every value has the
435          * value of "Add" added to it.
436          */
437         static const u16 uc_run_table[][3] = { /* Start, End, Add */
438         {0x0061, 0x007b,   -32}, {0x00e0, 0x00f7,  -32}, {0x00f8, 0x00ff, -32},
439         {0x0256, 0x0258,  -205}, {0x028a, 0x028c, -217}, {0x037b, 0x037e, 130},
440         {0x03ac, 0x03ad,   -38}, {0x03ad, 0x03b0,  -37}, {0x03b1, 0x03c2, -32},
441         {0x03c2, 0x03c3,   -31}, {0x03c3, 0x03cc,  -32}, {0x03cc, 0x03cd, -64},
442         {0x03cd, 0x03cf,   -63}, {0x0430, 0x0450,  -32}, {0x0450, 0x0460, -80},
443         {0x0561, 0x0587,   -48}, {0x1f00, 0x1f08,    8}, {0x1f10, 0x1f16,   8},
444         {0x1f20, 0x1f28,     8}, {0x1f30, 0x1f38,    8}, {0x1f40, 0x1f46,   8},
445         {0x1f51, 0x1f52,     8}, {0x1f53, 0x1f54,    8}, {0x1f55, 0x1f56,   8},
446         {0x1f57, 0x1f58,     8}, {0x1f60, 0x1f68,    8}, {0x1f70, 0x1f72,  74},
447         {0x1f72, 0x1f76,    86}, {0x1f76, 0x1f78,  100}, {0x1f78, 0x1f7a, 128},
448         {0x1f7a, 0x1f7c,   112}, {0x1f7c, 0x1f7e,  126}, {0x1f80, 0x1f88,   8},
449         {0x1f90, 0x1f98,     8}, {0x1fa0, 0x1fa8,    8}, {0x1fb0, 0x1fb2,   8},
450         {0x1fb3, 0x1fb4,     9}, {0x1fcc, 0x1fcd,   -9}, {0x1fd0, 0x1fd2,   8},
451         {0x1fe0, 0x1fe2,     8}, {0x1fe5, 0x1fe6,    7}, {0x1ffc, 0x1ffd,  -9},
452         {0x2170, 0x2180,   -16}, {0x24d0, 0x24ea,  -26}, {0x2c30, 0x2c5f, -48},
453         {0x2d00, 0x2d26, -7264}, {0xff41, 0xff5b,  -32},
454         };
455         /*
456          * "Start" is exclusive and "End" is inclusive, every second value is
457          * decremented by one.
458          */
459         static const u16 uc_dup_table[][2] = { /* Start, End */
460         {0x0100, 0x012f}, {0x0132, 0x0137}, {0x0139, 0x0149}, {0x014a, 0x0178},
461         {0x0179, 0x017e}, {0x01a0, 0x01a6}, {0x01b3, 0x01b7}, {0x01cd, 0x01dd},
462         {0x01de, 0x01ef}, {0x01f4, 0x01f5}, {0x01f8, 0x01f9}, {0x01fa, 0x0220},
463         {0x0222, 0x0234}, {0x023b, 0x023c}, {0x0241, 0x0242}, {0x0246, 0x024f},
464         {0x03d8, 0x03ef}, {0x03f7, 0x03f8}, {0x03fa, 0x03fb}, {0x0460, 0x0481},
465         {0x048a, 0x04bf}, {0x04c1, 0x04c4}, {0x04c5, 0x04c8}, {0x04c9, 0x04ce},
466         {0x04ec, 0x04ed}, {0x04d0, 0x04eb}, {0x04ee, 0x04f5}, {0x04f6, 0x0513},
467         {0x1e00, 0x1e95}, {0x1ea0, 0x1ef9}, {0x2183, 0x2184}, {0x2c60, 0x2c61},
468         {0x2c67, 0x2c6c}, {0x2c75, 0x2c76}, {0x2c80, 0x2ce3},
469         };
470         /*
471          * Set the Unicode character at offset "Offset" to "Value".  Note,
472          * "Value" is host endian.
473          */
474         static const u16 uc_byte_table[][2] = { /* Offset, Value */
475         {0x00ff, 0x0178}, {0x0180, 0x0243}, {0x0183, 0x0182}, {0x0185, 0x0184},
476         {0x0188, 0x0187}, {0x018c, 0x018b}, {0x0192, 0x0191}, {0x0195, 0x01f6},
477         {0x0199, 0x0198}, {0x019a, 0x023d}, {0x019e, 0x0220}, {0x01a8, 0x01a7},
478         {0x01ad, 0x01ac}, {0x01b0, 0x01af}, {0x01b9, 0x01b8}, {0x01bd, 0x01bc},
479         {0x01bf, 0x01f7}, {0x01c6, 0x01c4}, {0x01c9, 0x01c7}, {0x01cc, 0x01ca},
480         {0x01dd, 0x018e}, {0x01f3, 0x01f1}, {0x023a, 0x2c65}, {0x023e, 0x2c66},
481         {0x0253, 0x0181}, {0x0254, 0x0186}, {0x0259, 0x018f}, {0x025b, 0x0190},
482         {0x0260, 0x0193}, {0x0263, 0x0194}, {0x0268, 0x0197}, {0x0269, 0x0196},
483         {0x026b, 0x2c62}, {0x026f, 0x019c}, {0x0272, 0x019d}, {0x0275, 0x019f},
484         {0x027d, 0x2c64}, {0x0280, 0x01a6}, {0x0283, 0x01a9}, {0x0288, 0x01ae},
485         {0x0289, 0x0244}, {0x028c, 0x0245}, {0x0292, 0x01b7}, {0x03f2, 0x03f9},
486         {0x04cf, 0x04c0}, {0x1d7d, 0x2c63}, {0x214e, 0x2132},
487         };
488
489         for (u32 i = 0; i < 65536; i++)
490                 upcase[i] = i;
491
492         for (u32 r = 0; r < ARRAY_LEN(uc_run_table); r++)
493                 for (u32 i = uc_run_table[r][0]; i < uc_run_table[r][1]; i++)
494                         upcase[i] = i + uc_run_table[r][2];
495
496         for (u32 r = 0; r < ARRAY_LEN(uc_dup_table); r++)
497                 for (u32 i = uc_dup_table[r][0]; i < uc_dup_table[r][1]; i += 2)
498                         upcase[i + 1] = i;
499
500         for (u32 r = 0; r < ARRAY_LEN(uc_byte_table); r++)
501                 upcase[uc_byte_table[r][0]] = uc_byte_table[r][1];
502
503 #if 0
504         /* Sanity checks  */
505         wimlib_assert(upcase['a'] == 'A');
506         wimlib_assert(upcase['A'] == 'A');
507         wimlib_assert(upcase['z'] == 'Z');
508         wimlib_assert(upcase['Z'] == 'Z');
509         wimlib_assert(upcase['1'] == '1');
510         wimlib_assert(upcase[0x00e9] == 0x00c9); /* Latin letter e, with acute accent  */
511         wimlib_assert(upcase[0x00c9] == 0x00c9);
512         wimlib_assert(upcase[0x03c1] == 0x03a1); /* Greek letter rho  */
513         wimlib_assert(upcase[0x03a1] == 0x03a1);
514         wimlib_assert(upcase[0x0436] == 0x0416); /* Cyrillic letter zhe  */
515         wimlib_assert(upcase[0x0416] == 0x0416);
516         wimlib_assert(upcase[0x0567] == 0x0537); /* Armenian letter eh  */
517         wimlib_assert(upcase[0x0537] == 0x0537);
518         wimlib_assert(upcase[0x24d0] == 0x24b6); /* Circled Latin letter A
519                                                     (is that a real character???)  */
520         wimlib_assert(upcase[0x24b6] == 0x24b6);
521         wimlib_assert(upcase[0x2603] == 0x2603); /* Note to self: Upper case
522                                                     snowman symbol does not
523                                                     exist.  */
524 #endif
525 }
526
527 /* Compare UTF-16LE strings case-sensitively (%ignore_case == false) or
528  * case-insensitively (%ignore_case == true).
529  *
530  * This is implemented using the default upper-case table used by NTFS.  It does
531  * not handle all possible cases allowed by UTF-16LE.  For example, different
532  * normalizations of the same sequence of "characters" are not considered equal.
533  * It hopefully does the right thing most of the time though.  */
534 int
535 cmp_utf16le_strings(const utf16lechar *s1, size_t n1,
536                     const utf16lechar *s2, size_t n2,
537                     bool ignore_case)
538 {
539         size_t n = min(n1, n2);
540
541         if (ignore_case) {
542                 for (size_t i = 0; i < n; i++) {
543                         u16 c1 = upcase[le16_to_cpu(s1[i])];
544                         u16 c2 = upcase[le16_to_cpu(s2[i])];
545                         if (c1 != c2)
546                                 return (c1 < c2) ? -1 : 1;
547                 }
548         } else {
549                 for (size_t i = 0; i < n; i++) {
550                         u16 c1 = le16_to_cpu(s1[i]);
551                         u16 c2 = le16_to_cpu(s2[i]);
552                         if (c1 != c2)
553                                 return (c1 < c2) ? -1 : 1;
554                 }
555         }
556         if (n1 == n2)
557                 return 0;
558         return (n1 < n2) ? -1 : 1;
559 }
560
561 /* Duplicates a string of system-dependent encoding into a UTF-16LE string and
562  * returns the string and its length, in bytes, in the pointer arguments.  Frees
563  * any existing string at the return location before overwriting it. */
564 int
565 get_utf16le_string(const tchar *name, utf16lechar **name_utf16le_ret,
566                    u16 *name_utf16le_nbytes_ret)
567 {
568         utf16lechar *name_utf16le;
569         size_t name_utf16le_nbytes;
570         int ret;
571 #if TCHAR_IS_UTF16LE
572         name_utf16le_nbytes = tstrlen(name) * sizeof(utf16lechar);
573         name_utf16le = MALLOC(name_utf16le_nbytes + sizeof(utf16lechar));
574         if (name_utf16le == NULL)
575                 return WIMLIB_ERR_NOMEM;
576         memcpy(name_utf16le, name, name_utf16le_nbytes + sizeof(utf16lechar));
577         ret = 0;
578 #else
579
580         ret = tstr_to_utf16le(name, tstrlen(name), &name_utf16le,
581                               &name_utf16le_nbytes);
582         if (ret == 0) {
583                 if (name_utf16le_nbytes > 0xffff) {
584                         FREE(name_utf16le);
585                         ERROR("Multibyte string \"%"TS"\" is too long!", name);
586                         ret = WIMLIB_ERR_INVALID_UTF8_STRING;
587                 }
588         }
589 #endif
590         if (ret == 0) {
591                 FREE(*name_utf16le_ret);
592                 *name_utf16le_ret = name_utf16le;
593                 *name_utf16le_nbytes_ret = name_utf16le_nbytes;
594         }
595         return ret;
596 }
597