unicode.c 9.91 KB
Newer Older
1
/*****************************************************************************
2
 * unicode.c: Unicode <-> locale functions
3
 *****************************************************************************
4
 * Copyright (C) 2005-2006 the VideoLAN team
5
 * Copyright © 2005-2008 Rémi Denis-Courmont
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
 *
 * Authors: Rémi Denis-Courmont <rem # videolan.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
dionoea's avatar
dionoea committed
21
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22
23
24
25
26
 *****************************************************************************/

/*****************************************************************************
 * Preamble
 *****************************************************************************/
27
28
29
30
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

31
#include <vlc_common.h>
zorglub's avatar
zorglub committed
32
#include <vlc_charset.h>
33

34
#include <assert.h>
35

36
#include <stdio.h>
37
#include <stdarg.h>
38
#include <stdlib.h>
39
#include <sys/types.h>
40
41
42
#ifdef UNDER_CE
#  include <tchar.h>
#endif
Laurent Aimar's avatar
Laurent Aimar committed
43
#include <errno.h>
44

45
#if defined (__APPLE__) || defined (HAVE_MAEMO)
46
47
48
49
/* Define this if the OS always use UTF-8 internally */
# define ASSUME_UTF8 1
#endif

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
50
51
52
53
54
55
56
57
#if defined (ASSUME_UTF8)
/* Cool */
#elif defined (WIN32) || defined (UNDER_CE)
# define USE_MB2MB 1
#elif defined (HAVE_ICONV)
# define USE_ICONV 1
#else
# error No UTF8 charset conversion implemented on this platform!
58
59
#endif

60
#if defined (USE_ICONV)
61
62
# include <langinfo.h>
static char charset[sizeof ("CSISO11SWEDISHFORNAMES")] = "";
63

64
static void find_charset_once (void)
65
{
66
67
68
69
    strlcpy (charset, nl_langinfo (CODESET), sizeof (charset));
    if (!strcasecmp (charset, "ASCII")
     || !strcasecmp (charset, "ANSI_X3.4-1968"))
        strcpy (charset, "UTF-8"); /* superset... */
70
71
}

72
static int find_charset (void)
73
{
74
75
    static pthread_once_t once = PTHREAD_ONCE_INIT;
    pthread_once (&once, find_charset_once);
76
    return !strcasecmp (charset, "UTF-8");
77
}
78
79
#endif

80

81
static char *locale_fast (const char *string, bool from)
82
{
83
84
85
    if( string == NULL )
        return NULL;

86
#if defined (USE_ICONV)
87
88
    if (find_charset ())
        return (char *)string;
89

90
91
    vlc_iconv_t hd = vlc_iconv_open (from ? "UTF-8" : charset,
                                     from ? charset : "UTF-8");
92
    if (hd == (vlc_iconv_t)(-1))
93
        return NULL; /* Uho! */
94
95
96
97
98
99
100
101
102
103
104
105

    const char *iptr = string;
    size_t inb = strlen (string);
    size_t outb = inb * 6 + 1;
    char output[outb], *optr = output;

    while (vlc_iconv (hd, &iptr, &inb, &optr, &outb) == (size_t)(-1))
    {
        *optr++ = '?';
        outb--;
        iptr++;
        inb--;
106
        vlc_iconv (hd, NULL, NULL, NULL, NULL); /* reset */
107
108
    }
    *optr = '\0';
109
    vlc_iconv_close (hd);
110
111
112
113
114
115
116

    assert (inb == 0);
    assert (*iptr == '\0');
    assert (*optr == '\0');
    assert (strlen (output) == (size_t)(optr - output));
    return strdup (output);
#elif defined (USE_MB2MB)
117
    char *out;
118
    int len;
119

120
121
    len = 1 + MultiByteToWideChar (from ? CP_ACP : CP_UTF8,
                                   0, string, -1, NULL, 0);
122
123
124
    wchar_t *wide = malloc (len * sizeof (wchar_t));
    if (wide == NULL)
        return NULL;
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
125

damienf's avatar
damienf committed
126
    MultiByteToWideChar (from ? CP_ACP : CP_UTF8, 0, string, -1, wide, len);
127
128
    len = 1 + WideCharToMultiByte (from ? CP_UTF8 : CP_ACP, 0, wide, -1,
                                   NULL, 0, NULL, NULL);
129
    out = malloc (len);
130
131
132
133
    if (out != NULL)
        WideCharToMultiByte (from ? CP_UTF8 : CP_ACP, 0, wide, -1, out, len,
                             NULL, NULL);
    free (wide);
134
    return out;
135
#else
136
    (void)from;
137
138
139
140
141
    return (char *)string;
#endif
}


142
static inline char *locale_dup (const char *string, bool from)
143
{
Rafaël Carré's avatar
Rafaël Carré committed
144
145
    assert( string );

146
#if defined (USE_ICONV)
147
148
149
    if (find_charset ())
        return strdup (string);
    return locale_fast (string, from);
150
#elif defined (USE_MB2MB)
151
    return locale_fast (string, from);
152
#else
153
    (void)from;
154
155
    return strdup (string);
#endif
156
}
157

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
158
159
160
161
/**
 * Releases (if needed) a localized or uniformized string.
 * @param str non-NULL return value from FromLocale() or ToLocale().
 */
162
163
164
void LocaleFree (const char *str)
{
#if defined (USE_ICONV)
165
    if (!find_charset ())
166
167
168
        free ((char *)str);
#elif defined (USE_MB2MB)
    free ((char *)str);
169
#else
170
    (void)str;
171
#endif
172
173
}

174

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
175
/**
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
176
 * Converts a string from the system locale character encoding to UTF-8.
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
177
 *
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
178
 * @param locale nul-terminated string to convert
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
179
180
181
182
183
 *
 * @return a nul-terminated UTF-8 string, or NULL in case of error.
 * To avoid memory leak, you have to pass the result to LocaleFree()
 * when it is no longer needed.
 */
184
char *FromLocale (const char *locale)
185
{
186
    return locale_fast (locale, true);
187
188
}

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
189
190
191
192
193
194
195
196
197
/**
 * converts a string from the system locale character encoding to utf-8,
 * the result is always allocated on the heap.
 *
 * @param locale nul-terminated string to convert
 *
 * @return a nul-terminated utf-8 string, or null in case of error.
 * The result must be freed using free() - as with the strdup() function.
 */
198
char *FromLocaleDup (const char *locale)
199
{
200
    return locale_dup (locale, true);
201
202
203
}


Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
204
/**
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
205
 * ToLocale: converts an UTF-8 string to local system encoding.
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
206
207
208
209
210
211
212
 *
 * @param utf8 nul-terminated string to be converted
 *
 * @return a nul-terminated string, or NULL in case of error.
 * To avoid memory leak, you have to pass the result to LocaleFree()
 * when it is no longer needed.
 */
213
char *ToLocale (const char *utf8)
214
{
215
    return locale_fast (utf8, false);
216
217
}

218

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
219
220
221
222
223
224
225
226
227
/**
 * converts a string from UTF-8 to the system locale character encoding,
 * the result is always allocated on the heap.
 *
 * @param utf8 nul-terminated string to convert
 *
 * @return a nul-terminated string, or null in case of error.
 * The result must be freed using free() - as with the strdup() function.
 */
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
228
char *ToLocaleDup (const char *utf8)
229
{
230
    return locale_dup (utf8, false);
231
232
}

233
/**
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
234
235
 * Formats an UTF-8 string as vasprintf(), then print it to stdout, with
 * appropriate conversion to local encoding.
236
 */
237
static int utf8_vasprintf( char **str, const char *fmt, va_list ap )
238
{
239
240
241
242
243
244
245
246
    char *utf8;
    int res = vasprintf( &utf8, fmt, ap );
    if( res == -1 )
        return -1;

    *str = ToLocaleDup( utf8 );
    free( utf8 );
    return res;
247
248
}

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
249
250
251
252
/**
 * Formats an UTF-8 string as vfprintf(), then print it, with
 * appropriate conversion to local encoding.
 */
253
int utf8_vfprintf( FILE *stream, const char *fmt, va_list ap )
254
{
255
256
257
258
259
260
261
262
    char *str;
    int res = utf8_vasprintf( &str, fmt, ap );
    if( res == -1 )
        return -1;

    fputs( str, stream );
    free( str );
    return res;
263
264
}

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
265
266
267
268
/**
 * Formats an UTF-8 string as fprintf(), then print it, with
 * appropriate conversion to local encoding.
 */
269
270
int utf8_fprintf( FILE *stream, const char *fmt, ... )
{
271
272
    va_list ap;
    int res;
273

274
275
276
277
    va_start( ap, fmt );
    res = utf8_vfprintf( stream, fmt, ap );
    va_end( ap );
    return res;
278
279
}

280
281

static char *CheckUTF8( char *str, char rep )
282
{
283
    uint8_t *ptr = (uint8_t *)str;
284
285
    assert (str != NULL);

286
    for (;;)
287
    {
288
289
290
291
292
        uint8_t c = ptr[0];

        if (c == '\0')
            break;

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
293
294
        if (c > 0xF4)
            goto error;
295

Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
296
        int charlen = clz8 (c ^ 0xFF);
297
        switch (charlen)
298
        {
299
300
301
302
303
            case 0: // 7-bit ASCII character -> OK
                ptr++;
                continue;

            case 1: // continuation byte -> error
304
                goto error;
305
        }
306
307
308
309
310

        assert (charlen >= 2);

        uint32_t cp = c & ~((0xff >> (7 - charlen)) << (7 - charlen));
        for (int i = 1; i < charlen; i++)
311
        {
312
313
314
            assert (cp < (1 << 26));
            c = ptr[i];

315
            if ((c >> 6) != 2) // not a continuation byte
316
                goto error;
317
318

            cp = (cp << 6) | (ptr[i] & 0x3f);
319
        }
320
321
322
323

        if (cp < 128) // overlong (special case for ASCII)
            goto error;
        if (cp < (1u << (5 * charlen - 3))) // overlong
324
325
            goto error;

326
        ptr += charlen;
327
328
        continue;

329
330
    error:
        if (rep == 0)
331
            return NULL;
332
        *ptr++ = rep;
333
        str = NULL;
334
335
336
337
    }

    return str;
}
338

339
/**
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
340
 * Replaces invalid/overlong UTF-8 sequences with question marks.
341
342
343
344
345
346
347
348
349
350
351
352
 * Note that it is not possible to convert from Latin-1 to UTF-8 on the fly,
 * so we don't try that, even though it would be less disruptive.
 *
 * @return str if it was valid UTF-8, NULL if not.
 */
char *EnsureUTF8( char *str )
{
    return CheckUTF8( str, '?' );
}


/**
Rémi Denis-Courmont's avatar
Rémi Denis-Courmont committed
353
 * Checks whether a string is a valid UTF-8 byte sequence.
354
355
356
357
358
359
360
361
362
 *
 * @param str nul-terminated string to be checked
 *
 * @return str if it was valid UTF-8, NULL if not.
 */
const char *IsUTF8( const char *str )
{
    return CheckUTF8( (char *)str, 0 );
}
Laurent Aimar's avatar
Laurent Aimar committed
363
364
365
366
367
368
369

/**
 * Converts a string from the given character encoding to utf-8.
 *
 * @return a nul-terminated utf-8 string, or null in case of error.
 * The result must be freed using free().
 */
370
char *FromCharset(const char *charset, const void *data, size_t data_size)
Laurent Aimar's avatar
Laurent Aimar committed
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
{
    vlc_iconv_t handle = vlc_iconv_open ("UTF-8", charset);
    if (handle == (vlc_iconv_t)(-1))
        return NULL;

    char *out = NULL;
    for(unsigned mul = 4; mul < 8; mul++ )
    {
        size_t in_size = data_size;
        const char *in = data;
        size_t out_max = mul * data_size;
        char *tmp = out = malloc (1 + out_max);
        if (!out)
            break;

        if (vlc_iconv (handle, &in, &in_size, &tmp, &out_max) != (size_t)(-1)) {
            *tmp = '\0';
            break;
        }
        free(out);
        out = NULL;

        if (errno != E2BIG)
            break;
    }
    vlc_iconv_close(handle);
    return out;
}