apps/codecs/demac/libdemac/parser.c

   1 /*
   2
   3 libdemac - A Monkey's Audio decoder
   4
   5 $Id$
   6
   7 Copyright (C) Dave Chapman 2007
   8
   9 This program is free software; you can redistribute it and/or modify
  10 it under the terms of the GNU General Public License as published by
  11 the Free Software Foundation; either version 2 of the License, or
  12 (at your option) any later version.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA
  22
  23 */
  24
  25 #include <inttypes.h>
  26 #include <string.h>
  27 #ifndef ROCKBOX
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include <fcntl.h>
  33 #include <unistd.h>
  34 #endif
  35
  36 #include "parser.h"
  37
  38 #ifdef APE_MAX
  39 #undef APE_MAX
  40 #endif
  41 #define APE_MAX(a,b) ((a)>(b)?(a):(b))
  42
  43
  44 static inline int16_t get_int16(unsigned char* buf)
  45 {
  46     return(buf[0] | (buf[1] << 8));
  47 }
  48
  49 static inline uint16_t get_uint16(unsigned char* buf)
  50 {
  51     return(buf[0] | (buf[1] << 8));
  52 }
  53
  54 static inline uint32_t get_uint32(unsigned char* buf)
  55 {
  56     return(buf[0] | (buf[1] << 8) | (buf[2] << 16) | (buf[3] << 24));
  57 }
  58
  59
  60 int ape_parseheaderbuf(unsigned char* buf, struct ape_ctx_t* ape_ctx)
  61 {
  62     unsigned char* header;
  63
  64     memset(ape_ctx,0,sizeof(struct ape_ctx_t));
  65     /* TODO: Skip any leading junk such as id3v2 tags */
  66     ape_ctx->junklength = 0;
  67
  68     memcpy(ape_ctx->magic, buf, 4);
  69     if (memcmp(ape_ctx->magic,"MAC ",4)!=0)
  70     {
  71         return -1;
  72     }
  73
  74     ape_ctx->fileversion = get_int16(buf + 4);
  75
  76     if (ape_ctx->fileversion >= 3980)
  77     {
  78         ape_ctx->padding1 = get_int16(buf + 6);
  79         ape_ctx->descriptorlength = get_uint32(buf + 8);
  80         ape_ctx->headerlength = get_uint32(buf + 12);
  81         ape_ctx->seektablelength = get_uint32(buf + 16);
  82         ape_ctx->wavheaderlength = get_uint32(buf + 20);
  83         ape_ctx->audiodatalength = get_uint32(buf + 24);
  84         ape_ctx->audiodatalength_high = get_uint32(buf + 28);
  85         ape_ctx->wavtaillength = get_uint32(buf + 32);
  86         memcpy(ape_ctx->md5, buf + 36, 16);
  87
  88         header = buf + ape_ctx->descriptorlength;
  89
  90         /* Read header data */
  91         ape_ctx->compressiontype = get_uint16(header + 0);
  92         ape_ctx->formatflags = get_uint16(header + 2);
  93         ape_ctx->blocksperframe = get_uint32(header + 4);
  94         ape_ctx->finalframeblocks = get_uint32(header + 8);
  95         ape_ctx->totalframes = get_uint32(header + 12);
  96         ape_ctx->bps = get_uint16(header + 16);
  97         ape_ctx->channels = get_uint16(header + 18);
  98         ape_ctx->samplerate = get_uint32(header + 20);
  99
 100         ape_ctx->seektablefilepos = ape_ctx->junklength +
 101                                     ape_ctx->descriptorlength +
 102                                     ape_ctx->headerlength;
 103
 104         ape_ctx->firstframe = ape_ctx->junklength + ape_ctx->descriptorlength +
 105                               ape_ctx->headerlength + ape_ctx->seektablelength +
 106                               ape_ctx->wavheaderlength;
 107     } else {
 108         ape_ctx->headerlength = 32;
 109         ape_ctx->compressiontype = get_uint16(buf + 6);
 110         ape_ctx->formatflags = get_uint16(buf + 8);
 111         ape_ctx->channels = get_uint16(buf + 10);
 112         ape_ctx->samplerate = get_uint32(buf + 12);
 113         ape_ctx->wavheaderlength = get_uint32(buf + 16);
 114         ape_ctx->totalframes = get_uint32(buf + 24);
 115         ape_ctx->finalframeblocks = get_uint32(buf + 28);
 116
 117         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL)
 118         {
 119             ape_ctx->headerlength += 4;
 120         }
 121
 122         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS)
 123         {
 124             ape_ctx->seektablelength = get_uint32(buf + ape_ctx->headerlength);
 125             ape_ctx->seektablelength *= sizeof(int32_t);
 126             ape_ctx->headerlength += 4;
 127         } else {
 128             ape_ctx->seektablelength = ape_ctx->totalframes * sizeof(int32_t);
 129         }
 130
 131         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_8_BIT)
 132             ape_ctx->bps = 8;
 133         else if (ape_ctx->formatflags & MAC_FORMAT_FLAG_24_BIT)
 134             ape_ctx->bps = 24;
 135         else
 136             ape_ctx->bps = 16;
 137
 138         if (ape_ctx->fileversion >= 3950)
 139             ape_ctx->blocksperframe = 73728 * 4;
 140         else if ((ape_ctx->fileversion >= 3900) || (ape_ctx->fileversion >= 3800 && ape_ctx->compressiontype >= 4000))
 141             ape_ctx->blocksperframe = 73728;
 142         else
 143             ape_ctx->blocksperframe = 9216;
 144
 145         ape_ctx->seektablefilepos = ape_ctx->junklength + ape_ctx->headerlength +
 146                                     ape_ctx->wavheaderlength;
 147
 148         ape_ctx->firstframe = ape_ctx->junklength + ape_ctx->headerlength +
 149                               ape_ctx->wavheaderlength + ape_ctx->seektablelength;
 150     }
 151
 152     ape_ctx->totalsamples = ape_ctx->finalframeblocks;
 153     if (ape_ctx->totalframes > 1)
 154         ape_ctx->totalsamples += ape_ctx->blocksperframe * (ape_ctx->totalframes-1);
 155
 156     ape_ctx->numseekpoints = APE_MAX(ape_ctx->maxseekpoints,
 157                                      ape_ctx->seektablelength / sizeof(int32_t));
 158
 159     return 0;
 160 }
 161
 162
 163 #ifndef ROCKBOX
 164 /* Helper functions */
 165
 166 static int read_uint16(int fd, uint16_t* x)
 167 {
 168     unsigned char tmp[2];
 169     int n;
 170
 171     n = read(fd,tmp,2);
 172
 173     if (n != 2)
 174         return -1;
 175
 176     *x = tmp[0] | (tmp[1] << 8);
 177
 178     return 0;
 179 }
 180
 181 static int read_int16(int fd, int16_t* x)
 182 {
 183     return read_uint16(fd, (uint16_t*)x);
 184 }
 185
 186 static int read_uint32(int fd, uint32_t* x)
 187 {
 188     unsigned char tmp[4];
 189     int n;
 190
 191     n = read(fd,tmp,4);
 192
 193     if (n != 4)
 194         return -1;
 195
 196     *x = tmp[0] | (tmp[1] << 8) | (tmp[2] << 16) | (tmp[3] << 24);
 197
 198     return 0;
 199 }
 200
 201 int ape_parseheader(int fd, struct ape_ctx_t* ape_ctx)
 202 {
 203     int i,n;
 204
 205     /* TODO: Skip any leading junk such as id3v2 tags */
 206     ape_ctx->junklength = 0;
 207
 208     lseek(fd,ape_ctx->junklength,SEEK_SET);
 209
 210     n = read(fd,&ape_ctx->magic,4);
 211     if (n != 4) return -1;
 212
 213     if (memcmp(ape_ctx->magic,"MAC ",4)!=0)
 214     {
 215         return -1;
 216     }
 217
 218     if (read_int16(fd,&ape_ctx->fileversion) < 0)
 219         return -1;
 220
 221     if (ape_ctx->fileversion >= 3980)
 222     {
 223         if (read_int16(fd,&ape_ctx->padding1) < 0)
 224             return -1;
 225         if (read_uint32(fd,&ape_ctx->descriptorlength) < 0)
 226             return -1;
 227         if (read_uint32(fd,&ape_ctx->headerlength) < 0)
 228             return -1;
 229         if (read_uint32(fd,&ape_ctx->seektablelength) < 0)
 230             return -1;
 231         if (read_uint32(fd,&ape_ctx->wavheaderlength) < 0)
 232             return -1;
 233         if (read_uint32(fd,&ape_ctx->audiodatalength) < 0)
 234             return -1;
 235         if (read_uint32(fd,&ape_ctx->audiodatalength_high) < 0)
 236             return -1;
 237         if (read_uint32(fd,&ape_ctx->wavtaillength) < 0)
 238             return -1;
 239         if (read(fd,&ape_ctx->md5,16) != 16)
 240             return -1;
 241
 242         /* Skip any unknown bytes at the end of the descriptor.  This is for future
 243            compatibility */
 244         if (ape_ctx->descriptorlength > 52)
 245             lseek(fd,ape_ctx->descriptorlength - 52, SEEK_CUR);
 246
 247         /* Read header data */
 248         if (read_uint16(fd,&ape_ctx->compressiontype) < 0)
 249             return -1;
 250         if (read_uint16(fd,&ape_ctx->formatflags) < 0)
 251             return -1;
 252         if (read_uint32(fd,&ape_ctx->blocksperframe) < 0)
 253             return -1;
 254         if (read_uint32(fd,&ape_ctx->finalframeblocks) < 0)
 255             return -1;
 256         if (read_uint32(fd,&ape_ctx->totalframes) < 0)
 257             return -1;
 258         if (read_uint16(fd,&ape_ctx->bps) < 0)
 259             return -1;
 260         if (read_uint16(fd,&ape_ctx->channels) < 0)
 261             return -1;
 262         if (read_uint32(fd,&ape_ctx->samplerate) < 0)
 263             return -1;
 264     } else {
 265         ape_ctx->descriptorlength = 0;
 266         ape_ctx->headerlength = 32;
 267
 268         if (read_uint16(fd,&ape_ctx->compressiontype) < 0)
 269             return -1;
 270         if (read_uint16(fd,&ape_ctx->formatflags) < 0)
 271             return -1;
 272         if (read_uint16(fd,&ape_ctx->channels) < 0)
 273             return -1;
 274         if (read_uint32(fd,&ape_ctx->samplerate) < 0)
 275             return -1;
 276         if (read_uint32(fd,&ape_ctx->wavheaderlength) < 0)
 277             return -1;
 278         if (read_uint32(fd,&ape_ctx->wavtaillength) < 0)
 279             return -1;
 280         if (read_uint32(fd,&ape_ctx->totalframes) < 0)
 281             return -1;
 282         if (read_uint32(fd,&ape_ctx->finalframeblocks) < 0)
 283             return -1;
 284
 285         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL)
 286         {
 287             lseek(fd, 4, SEEK_CUR);   /* Skip the peak level */
 288             ape_ctx->headerlength += 4;
 289         }
 290
 291         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS)
 292         {
 293             if (read_uint32(fd,&ape_ctx->seektablelength) < 0)
 294                 return -1;
 295             ape_ctx->headerlength += 4;
 296             ape_ctx->seektablelength *= sizeof(int32_t);
 297         } else {
 298             ape_ctx->seektablelength = ape_ctx->totalframes * sizeof(int32_t);
 299         }
 300
 301         if (ape_ctx->formatflags & MAC_FORMAT_FLAG_8_BIT)
 302             ape_ctx->bps = 8;
 303         else if (ape_ctx->formatflags & MAC_FORMAT_FLAG_24_BIT)
 304             ape_ctx->bps = 24;
 305         else
 306             ape_ctx->bps = 16;
 307
 308         if (ape_ctx->fileversion >= 3950)
 309             ape_ctx->blocksperframe = 73728 * 4;
 310         else if ((ape_ctx->fileversion >= 3900) || (ape_ctx->fileversion >= 3800 && ape_ctx->compressiontype >= 4000))
 311             ape_ctx->blocksperframe = 73728;
 312         else
 313             ape_ctx->blocksperframe = 9216;
 314
 315         /* Skip any stored wav header */
 316         if (!(ape_ctx->formatflags & MAC_FORMAT_FLAG_CREATE_WAV_HEADER))
 317         {
 318             lseek(fd, ape_ctx->wavheaderlength, SEEK_CUR);
 319         }
 320     }
 321
 322     ape_ctx->totalsamples = ape_ctx->finalframeblocks;
 323     if (ape_ctx->totalframes > 1)
 324         ape_ctx->totalsamples += ape_ctx->blocksperframe * (ape_ctx->totalframes-1);
 325
 326     if (ape_ctx->seektablelength > 0)
 327     {
 328         ape_ctx->seektable = malloc(ape_ctx->seektablelength);
 329         if (ape_ctx->seektable == NULL)
 330             return -1;
 331         for (i=0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++)
 332         {
 333             if (read_uint32(fd,&ape_ctx->seektable[i]) < 0)
 334             {
 335                  free(ape_ctx->seektable);
 336                  return -1;
 337             }
 338         }
 339     }
 340
 341     ape_ctx->firstframe = ape_ctx->junklength + ape_ctx->descriptorlength +
 342                            ape_ctx->headerlength + ape_ctx->seektablelength +
 343                            ape_ctx->wavheaderlength;
 344
 345     return 0;
 346 }
 347
 348 void ape_dumpinfo(struct ape_ctx_t* ape_ctx)
 349 {
 350   int i;
 351
 352     printf("Descriptor Block:\n\n");
 353     printf("magic                = \"%c%c%c%c\"\n",
 354             ape_ctx->magic[0],ape_ctx->magic[1],
 355             ape_ctx->magic[2],ape_ctx->magic[3]);
 356     printf("fileversion          = %d\n",ape_ctx->fileversion);
 357     printf("descriptorlength     = %d\n",ape_ctx->descriptorlength);
 358     printf("headerlength         = %d\n",ape_ctx->headerlength);
 359     printf("seektablelength      = %d\n",ape_ctx->seektablelength);
 360     printf("wavheaderlength      = %d\n",ape_ctx->wavheaderlength);
 361     printf("audiodatalength      = %d\n",ape_ctx->audiodatalength);
 362     printf("audiodatalength_high = %d\n",ape_ctx->audiodatalength_high);
 363     printf("wavtaillength        = %d\n",ape_ctx->wavtaillength);
 364     printf("md5                  = ");
 365     for (i = 0; i < 16; i++)
 366         printf("%02x",ape_ctx->md5[i]);
 367     printf("\n");
 368
 369     printf("\nHeader Block:\n\n");
 370
 371     printf("compressiontype      = %d\n",ape_ctx->compressiontype);
 372     printf("formatflags          = %d\n",ape_ctx->formatflags);
 373     printf("blocksperframe       = %d\n",ape_ctx->blocksperframe);
 374     printf("finalframeblocks     = %d\n",ape_ctx->finalframeblocks);
 375     printf("totalframes          = %d\n",ape_ctx->totalframes);
 376     printf("bps                  = %d\n",ape_ctx->bps);
 377     printf("channels             = %d\n",ape_ctx->channels);
 378     printf("samplerate           = %d\n",ape_ctx->samplerate);
 379
 380     printf("\nSeektable\n\n");
 381     if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes)
 382     {
 383         printf("No seektable\n");
 384     }
 385     else
 386     {
 387         for ( i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t) ; i++)
 388         {
 389             if (i < ape_ctx->totalframes-1) {
 390                 printf("%8d   %d (%d bytes)\n",i,ape_ctx->seektable[i],ape_ctx->seektable[i+1]-ape_ctx->seektable[i]);
 391             } else {
 392                 printf("%8d   %d\n",i,ape_ctx->seektable[i]);
 393             }
 394         }
 395     }
 396     printf("\nCalculated information:\n\n");
 397     printf("junklength           = %d\n",ape_ctx->junklength);
 398     printf("firstframe           = %d\n",ape_ctx->firstframe);
 399     printf("totalsamples         = %d\n",ape_ctx->totalsamples);
 400 }
 401
 402 #endif /* !ROCKBOX */