icy2utf8.c

Go to the documentation of this file.

/* mpg123 note: This is BSD-licensed code that is no problem for mpg123 usage under LGPL.
   It's Free, understood? ;-) */
 
/* Another note: This code is basically written by Thorsten Glaser,
   Thomas Orgis did just some rearrangements and comments. */
 
/*-
 * Copyright (c) 2008
 *  Thorsten Glaser <tg@mirbsd.org>
 *
 * Provided that these terms and disclaimer and all copyright notices
 * are retained or reproduced in an accompanying document, permission
 * is granted to deal in this work without restriction, including un-
 * limited rights to use, publicly perform, distribute, sell, modify,
 * merge, give away, or sublicence.
 *
 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
 * the utmost extent permitted by applicable law, neither express nor
 * implied; without malicious intent or gross negligence. In no event
 * may a licensor, author or contributor be held liable for indirect,
 * direct, other damage, loss, or other issues arising in any way out
 * of dealing in the work, even if advised of the possibility of such
 * damage or existence of a defect, except proven that it results out
 * of said person's immediate fault when using the work as intended.
 *-
 * Convert from ICY encoding (windows-1252 codepage) to UTF-8
 */
 
#include "config.h"
#include "intsym.h"
/* Includes string and stdlib headers... */
#include "compat.h"
 
/* ThOr: too lazy for this type check; also we use char/short all around anyway.
   Of cource, it would be the proper way to use _these_ kind of types all around. */
#define uint8_t  unsigned char
#define uint16_t unsigned short
 
static const uint8_t cp1252_utf8[] = {
    /* 0x00 @   0 */    0x00,
    /* 0x01 @   1 */    0x01,
    /* 0x02 @   2 */    0x02,
    /* 0x03 @   3 */    0x03,
    /* 0x04 @   4 */    0x04,
    /* 0x05 @   5 */    0x05,
    /* 0x06 @   6 */    0x06,
    /* 0x07 @   7 */    0x07,
    /* 0x08 @   8 */    0x08,
    /* 0x09 @   9 */    0x09,
    /* 0x0A @  10 */    0x0A,
    /* 0x0B @  11 */    0x0B,
    /* 0x0C @  12 */    0x0C,
    /* 0x0D @  13 */    0x0D,
    /* 0x0E @  14 */    0x0E,
    /* 0x0F @  15 */    0x0F,
    /* 0x10 @  16 */    0x10,
    /* 0x11 @  17 */    0x11,
    /* 0x12 @  18 */    0x12,
    /* 0x13 @  19 */    0x13,
    /* 0x14 @  20 */    0x14,
    /* 0x15 @  21 */    0x15,
    /* 0x16 @  22 */    0x16,
    /* 0x17 @  23 */    0x17,
    /* 0x18 @  24 */    0x18,
    /* 0x19 @  25 */    0x19,
    /* 0x1A @  26 */    0x1A,
    /* 0x1B @  27 */    0x1B,
    /* 0x1C @  28 */    0x1C,
    /* 0x1D @  29 */    0x1D,
    /* 0x1E @  30 */    0x1E,
    /* 0x1F @  31 */    0x1F,
    /* 0x20 @  32 */    0x20,
    /* 0x21 @  33 */    0x21,
    /* 0x22 @  34 */    0x22,
    /* 0x23 @  35 */    0x23,
    /* 0x24 @  36 */    0x24,
    /* 0x25 @  37 */    0x25,
    /* 0x26 @  38 */    0x26,
    /* 0x27 @  39 */    0x27,
    /* 0x28 @  40 */    0x28,
    /* 0x29 @  41 */    0x29,
    /* 0x2A @  42 */    0x2A,
    /* 0x2B @  43 */    0x2B,
    /* 0x2C @  44 */    0x2C,
    /* 0x2D @  45 */    0x2D,
    /* 0x2E @  46 */    0x2E,
    /* 0x2F @  47 */    0x2F,
    /* 0x30 @  48 */    0x30,
    /* 0x31 @  49 */    0x31,
    /* 0x32 @  50 */    0x32,
    /* 0x33 @  51 */    0x33,
    /* 0x34 @  52 */    0x34,
    /* 0x35 @  53 */    0x35,
    /* 0x36 @  54 */    0x36,
    /* 0x37 @  55 */    0x37,
    /* 0x38 @  56 */    0x38,
    /* 0x39 @  57 */    0x39,
    /* 0x3A @  58 */    0x3A,
    /* 0x3B @  59 */    0x3B,
    /* 0x3C @  60 */    0x3C,
    /* 0x3D @  61 */    0x3D,
    /* 0x3E @  62 */    0x3E,
    /* 0x3F @  63 */    0x3F,
    /* 0x40 @  64 */    0x40,
    /* 0x41 @  65 */    0x41,
    /* 0x42 @  66 */    0x42,
    /* 0x43 @  67 */    0x43,
    /* 0x44 @  68 */    0x44,
    /* 0x45 @  69 */    0x45,
    /* 0x46 @  70 */    0x46,
    /* 0x47 @  71 */    0x47,
    /* 0x48 @  72 */    0x48,
    /* 0x49 @  73 */    0x49,
    /* 0x4A @  74 */    0x4A,
    /* 0x4B @  75 */    0x4B,
    /* 0x4C @  76 */    0x4C,
    /* 0x4D @  77 */    0x4D,
    /* 0x4E @  78 */    0x4E,
    /* 0x4F @  79 */    0x4F,
    /* 0x50 @  80 */    0x50,
    /* 0x51 @  81 */    0x51,
    /* 0x52 @  82 */    0x52,
    /* 0x53 @  83 */    0x53,
    /* 0x54 @  84 */    0x54,
    /* 0x55 @  85 */    0x55,
    /* 0x56 @  86 */    0x56,
    /* 0x57 @  87 */    0x57,
    /* 0x58 @  88 */    0x58,
    /* 0x59 @  89 */    0x59,
    /* 0x5A @  90 */    0x5A,
    /* 0x5B @  91 */    0x5B,
    /* 0x5C @  92 */    0x5C,
    /* 0x5D @  93 */    0x5D,
    /* 0x5E @  94 */    0x5E,
    /* 0x5F @  95 */    0x5F,
    /* 0x60 @  96 */    0x60,
    /* 0x61 @  97 */    0x61,
    /* 0x62 @  98 */    0x62,
    /* 0x63 @  99 */    0x63,
    /* 0x64 @ 100 */    0x64,
    /* 0x65 @ 101 */    0x65,
    /* 0x66 @ 102 */    0x66,
    /* 0x67 @ 103 */    0x67,
    /* 0x68 @ 104 */    0x68,
    /* 0x69 @ 105 */    0x69,
    /* 0x6A @ 106 */    0x6A,
    /* 0x6B @ 107 */    0x6B,
    /* 0x6C @ 108 */    0x6C,
    /* 0x6D @ 109 */    0x6D,
    /* 0x6E @ 110 */    0x6E,
    /* 0x6F @ 111 */    0x6F,
    /* 0x70 @ 112 */    0x70,
    /* 0x71 @ 113 */    0x71,
    /* 0x72 @ 114 */    0x72,
    /* 0x73 @ 115 */    0x73,
    /* 0x74 @ 116 */    0x74,
    /* 0x75 @ 117 */    0x75,
    /* 0x76 @ 118 */    0x76,
    /* 0x77 @ 119 */    0x77,
    /* 0x78 @ 120 */    0x78,
    /* 0x79 @ 121 */    0x79,
    /* 0x7A @ 122 */    0x7A,
    /* 0x7B @ 123 */    0x7B,
    /* 0x7C @ 124 */    0x7C,
    /* 0x7D @ 125 */    0x7D,
    /* 0x7E @ 126 */    0x7E,
    /* 0x7F @ 127 */    0x7F,
    /* 0x80 @ 128 */    0xE2, 0x82, 0xAC,
    /* 0x81 @ 131 */    0xEF, 0xBF, 0xBD,
    /* 0x82 @ 134 */    0xE2, 0x80, 0x9A,
    /* 0x83 @ 137 */    0xC6, 0x92,
    /* 0x84 @ 139 */    0xE2, 0x80, 0x9E,
    /* 0x85 @ 142 */    0xE2, 0x80, 0xA6,
    /* 0x86 @ 145 */    0xE2, 0x80, 0xA0,
    /* 0x87 @ 148 */    0xE2, 0x80, 0xA1,
    /* 0x88 @ 151 */    0xCB, 0x86,
    /* 0x89 @ 153 */    0xE2, 0x80, 0xB0,
    /* 0x8A @ 156 */    0xC5, 0xA0,
    /* 0x8B @ 158 */    0xE2, 0x80, 0xB9,
    /* 0x8C @ 161 */    0xC5, 0x92,
    /* 0x8D @ 163 */    0xEF, 0xBF, 0xBD,
    /* 0x8E @ 166 */    0xC5, 0xBD,
    /* 0x8F @ 168 */    0xEF, 0xBF, 0xBD,
    /* 0x90 @ 171 */    0xEF, 0xBF, 0xBD,
    /* 0x91 @ 174 */    0xE2, 0x80, 0x98,
    /* 0x92 @ 177 */    0xE2, 0x80, 0x99,
    /* 0x93 @ 180 */    0xE2, 0x80, 0x9C,
    /* 0x94 @ 183 */    0xE2, 0x80, 0x9D,
    /* 0x95 @ 186 */    0xE2, 0x80, 0xA2,
    /* 0x96 @ 189 */    0xE2, 0x80, 0x93,
    /* 0x97 @ 192 */    0xE2, 0x80, 0x94,
    /* 0x98 @ 195 */    0xCB, 0x9C,
    /* 0x99 @ 197 */    0xE2, 0x84, 0xA2,
    /* 0x9A @ 200 */    0xC5, 0xA1,
    /* 0x9B @ 202 */    0xE2, 0x80, 0xBA,
    /* 0x9C @ 205 */    0xC5, 0x93,
    /* 0x9D @ 207 */    0xEF, 0xBF, 0xBD,
    /* 0x9E @ 210 */    0xC5, 0xBE,
    /* 0x9F @ 212 */    0xC5, 0xB8,
    /* 0xA0 @ 214 */    0xC2, 0xA0,
    /* 0xA1 @ 216 */    0xC2, 0xA1,
    /* 0xA2 @ 218 */    0xC2, 0xA2,
    /* 0xA3 @ 220 */    0xC2, 0xA3,
    /* 0xA4 @ 222 */    0xC2, 0xA4,
    /* 0xA5 @ 224 */    0xC2, 0xA5,
    /* 0xA6 @ 226 */    0xC2, 0xA6,
    /* 0xA7 @ 228 */    0xC2, 0xA7,
    /* 0xA8 @ 230 */    0xC2, 0xA8,
    /* 0xA9 @ 232 */    0xC2, 0xA9,
    /* 0xAA @ 234 */    0xC2, 0xAA,
    /* 0xAB @ 236 */    0xC2, 0xAB,
    /* 0xAC @ 238 */    0xC2, 0xAC,
    /* 0xAD @ 240 */    0xC2, 0xAD,
    /* 0xAE @ 242 */    0xC2, 0xAE,
    /* 0xAF @ 244 */    0xC2, 0xAF,
    /* 0xB0 @ 246 */    0xC2, 0xB0,
    /* 0xB1 @ 248 */    0xC2, 0xB1,
    /* 0xB2 @ 250 */    0xC2, 0xB2,
    /* 0xB3 @ 252 */    0xC2, 0xB3,
    /* 0xB4 @ 254 */    0xC2, 0xB4,
    /* 0xB5 @ 256 */    0xC2, 0xB5,
    /* 0xB6 @ 258 */    0xC2, 0xB6,
    /* 0xB7 @ 260 */    0xC2, 0xB7,
    /* 0xB8 @ 262 */    0xC2, 0xB8,
    /* 0xB9 @ 264 */    0xC2, 0xB9,
    /* 0xBA @ 266 */    0xC2, 0xBA,
    /* 0xBB @ 268 */    0xC2, 0xBB,
    /* 0xBC @ 270 */    0xC2, 0xBC,
    /* 0xBD @ 272 */    0xC2, 0xBD,
    /* 0xBE @ 274 */    0xC2, 0xBE,
    /* 0xBF @ 276 */    0xC2, 0xBF,
    /* 0xC0 @ 278 */    0xC3, 0x80,
    /* 0xC1 @ 280 */    0xC3, 0x81,
    /* 0xC2 @ 282 */    0xC3, 0x82,
    /* 0xC3 @ 284 */    0xC3, 0x83,
    /* 0xC4 @ 286 */    0xC3, 0x84,
    /* 0xC5 @ 288 */    0xC3, 0x85,
    /* 0xC6 @ 290 */    0xC3, 0x86,
    /* 0xC7 @ 292 */    0xC3, 0x87,
    /* 0xC8 @ 294 */    0xC3, 0x88,
    /* 0xC9 @ 296 */    0xC3, 0x89,
    /* 0xCA @ 298 */    0xC3, 0x8A,
    /* 0xCB @ 300 */    0xC3, 0x8B,
    /* 0xCC @ 302 */    0xC3, 0x8C,
    /* 0xCD @ 304 */    0xC3, 0x8D,
    /* 0xCE @ 306 */    0xC3, 0x8E,
    /* 0xCF @ 308 */    0xC3, 0x8F,
    /* 0xD0 @ 310 */    0xC3, 0x90,
    /* 0xD1 @ 312 */    0xC3, 0x91,
    /* 0xD2 @ 314 */    0xC3, 0x92,
    /* 0xD3 @ 316 */    0xC3, 0x93,
    /* 0xD4 @ 318 */    0xC3, 0x94,
    /* 0xD5 @ 320 */    0xC3, 0x95,
    /* 0xD6 @ 322 */    0xC3, 0x96,
    /* 0xD7 @ 324 */    0xC3, 0x97,
    /* 0xD8 @ 326 */    0xC3, 0x98,
    /* 0xD9 @ 328 */    0xC3, 0x99,
    /* 0xDA @ 330 */    0xC3, 0x9A,
    /* 0xDB @ 332 */    0xC3, 0x9B,
    /* 0xDC @ 334 */    0xC3, 0x9C,
    /* 0xDD @ 336 */    0xC3, 0x9D,
    /* 0xDE @ 338 */    0xC3, 0x9E,
    /* 0xDF @ 340 */    0xC3, 0x9F,
    /* 0xE0 @ 342 */    0xC3, 0xA0,
    /* 0xE1 @ 344 */    0xC3, 0xA1,
    /* 0xE2 @ 346 */    0xC3, 0xA2,
    /* 0xE3 @ 348 */    0xC3, 0xA3,
    /* 0xE4 @ 350 */    0xC3, 0xA4,
    /* 0xE5 @ 352 */    0xC3, 0xA5,
    /* 0xE6 @ 354 */    0xC3, 0xA6,
    /* 0xE7 @ 356 */    0xC3, 0xA7,
    /* 0xE8 @ 358 */    0xC3, 0xA8,
    /* 0xE9 @ 360 */    0xC3, 0xA9,
    /* 0xEA @ 362 */    0xC3, 0xAA,
    /* 0xEB @ 364 */    0xC3, 0xAB,
    /* 0xEC @ 366 */    0xC3, 0xAC,
    /* 0xED @ 368 */    0xC3, 0xAD,
    /* 0xEE @ 370 */    0xC3, 0xAE,
    /* 0xEF @ 372 */    0xC3, 0xAF,
    /* 0xF0 @ 374 */    0xC3, 0xB0,
    /* 0xF1 @ 376 */    0xC3, 0xB1,
    /* 0xF2 @ 378 */    0xC3, 0xB2,
    /* 0xF3 @ 380 */    0xC3, 0xB3,
    /* 0xF4 @ 382 */    0xC3, 0xB4,
    /* 0xF5 @ 384 */    0xC3, 0xB5,
    /* 0xF6 @ 386 */    0xC3, 0xB6,
    /* 0xF7 @ 388 */    0xC3, 0xB7,
    /* 0xF8 @ 390 */    0xC3, 0xB8,
    /* 0xF9 @ 392 */    0xC3, 0xB9,
    /* 0xFA @ 394 */    0xC3, 0xBA,
    /* 0xFB @ 396 */    0xC3, 0xBB,
    /* 0xFC @ 398 */    0xC3, 0xBC,
    /* 0xFD @ 400 */    0xC3, 0xBD,
    /* 0xFE @ 402 */    0xC3, 0xBE,
    /* 0xFF @ 404 */    0xC3, 0xBF,
};
 
static const uint16_t tblofs[257] = {
    /* 0x00 */   0,   1,   2,   3,   4,   5,   6,   7,
    /* 0x08 */   8,   9,  10,  11,  12,  13,  14,  15,
    /* 0x10 */  16,  17,  18,  19,  20,  21,  22,  23,
    /* 0x18 */  24,  25,  26,  27,  28,  29,  30,  31,
    /* 0x20 */  32,  33,  34,  35,  36,  37,  38,  39,
    /* 0x28 */  40,  41,  42,  43,  44,  45,  46,  47,
    /* 0x30 */  48,  49,  50,  51,  52,  53,  54,  55,
    /* 0x38 */  56,  57,  58,  59,  60,  61,  62,  63,
    /* 0x40 */  64,  65,  66,  67,  68,  69,  70,  71,
    /* 0x48 */  72,  73,  74,  75,  76,  77,  78,  79,
    /* 0x50 */  80,  81,  82,  83,  84,  85,  86,  87,
    /* 0x58 */  88,  89,  90,  91,  92,  93,  94,  95,
    /* 0x60 */  96,  97,  98,  99, 100, 101, 102, 103,
    /* 0x68 */ 104, 105, 106, 107, 108, 109, 110, 111,
    /* 0x70 */ 112, 113, 114, 115, 116, 117, 118, 119,
    /* 0x78 */ 120, 121, 122, 123, 124, 125, 126, 127,
    /* 0x80 */ 128, 131, 134, 137, 139, 142, 145, 148,
    /* 0x88 */ 151, 153, 156, 158, 161, 163, 166, 168,
    /* 0x90 */ 171, 174, 177, 180, 183, 186, 189, 192,
    /* 0x98 */ 195, 197, 200, 202, 205, 207, 210, 212,
    /* 0xA0 */ 214, 216, 218, 220, 222, 224, 226, 228,
    /* 0xA8 */ 230, 232, 234, 236, 238, 240, 242, 244,
    /* 0xB0 */ 246, 248, 250, 252, 254, 256, 258, 260,
    /* 0xB8 */ 262, 264, 266, 268, 270, 272, 274, 276,
    /* 0xC0 */ 278, 280, 282, 284, 286, 288, 290, 292,
    /* 0xC8 */ 294, 296, 298, 300, 302, 304, 306, 308,
    /* 0xD0 */ 310, 312, 314, 316, 318, 320, 322, 324,
    /* 0xD8 */ 326, 328, 330, 332, 334, 336, 338, 340,
    /* 0xE0 */ 342, 344, 346, 348, 350, 352, 354, 356,
    /* 0xE8 */ 358, 360, 362, 364, 366, 368, 370, 372,
    /* 0xF0 */ 374, 376, 378, 380, 382, 384, 386, 388,
    /* 0xF8 */ 390, 392, 394, 396, 398, 400, 402, 404,
    /* sizeof (cp1252_utf8) */ 406
};
 
/* Check if a string qualifies as UTF-8. */
static int
is_utf8(const char* src)
{
    uint8_t ch;
    size_t i;
    const uint8_t* s = (const uint8_t*) src;
 
    /* We make a loop over every character, until we find a null one.
       Remember: The string is supposed to end with a NUL, so ahead checks are safe. */
    while ((ch = *s++)) {
        /* Ye olde 7bit ASCII chars 'rr fine for anything */
        if(ch < 0x80) continue;
 
        /* Now, we watch out for non-UTF conform sequences. */
        else if ((ch < 0xC2) || (ch > 0xFD))
            return 0;
        /* check for some misformed sequences */
        if (((ch == 0xC2) && (s[0] < 0xA0)) ||
            ((ch == 0xEF) && (s[0] == 0xBF) && (s[1] > 0xBD)))
            /* XXX add more for outside the BMP */
            return 0;
 
        /* Check the continuation bytes. */
        if      (ch < 0xE0) i = 1;
        else if (ch < 0xF0) i = 2;
        else if (ch < 0xF8) i = 3;
        else if (ch < 0xFC) i = 4;
        else
            i = 5;
 
        while (i--)
            if ((*s++ & 0xC0) != 0x80)
                return 0;
    }
 
    /* If no check failed, the string indeed looks like valid UTF-8. */
    return 1;
}
 
/* The main conversion routine.
   ICY in CP-1252 (or UTF-8 alreay) to UTF-8 encoded string.
   If force is applied, it will always encode to UTF-8, without checking. */
char *
icy2utf8(const char *src, int force)
{
    const uint8_t *s = (const uint8_t *)src;
    size_t srclen, dstlen, i, k;
    uint8_t ch, *d;
    char *dst;
 
    /* Some funny streams from Apple/iTunes give ICY info in UTF-8 already.
       So, be prepared and don't try to re-encode such. Unless forced. */
    if(!force && is_utf8(src)) return (compat_strdup(src));
 
    srclen = strlen(src) + 1;
    /* allocate conservatively */
    if ((d = malloc(srclen * 3)) == NULL)
        return (NULL);
 
    i = 0;
    dstlen = 0;
    while (i < srclen) {
        ch = s[i++];
        k = tblofs[ch];
        while (k < tblofs[ch + 1])
            d[dstlen++] = cp1252_utf8[k++];
    }
 
    /* dstlen includes trailing NUL since srclen also does */
    if ((dst = realloc(d, dstlen)) == NULL) {
        free(d);
        return (NULL);
    }
    return (dst);
}
 
/* This stuff is for testing only. */
#ifdef TEST
static const char intext[] = "\225 Gr\374\337e kosten 0,55 \200\205";
 
#include <stdio.h>
 
int
main(void)
{
    char *t, *t2;
 
    if ((t = icy2utf8(intext, 0)) == NULL) {
        fprintf(stderr, "out of memory\n");
        return (1);
    }
 
    /* make sure it won't be converted twice */
    if ((t2 = icy2utf8(t), 0) == NULL) {
        fprintf(stderr, "out of memory\n");
        return (1);
    }
 
    printf("Result is:\t\343\200\214%s\343\200\215\n"
        "\t\t\343\200\214%s\343\200\215\n", t, t2);
 
    free(t);
    free(t2);
    return (0);
}
#endif