dlls/winemp3.acm/interface.c

   1 /*
   2  * Copyright (c) Michael Hipp and other authors of the mpglib project.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18
  19 #include <stdlib.h>
  20 #include <stdio.h>
  21
  22 #include "mpg123.h"
  23 #include "mpglib.h"
  24
  25
  26 BOOL InitMP3(struct mpstr *mp)
  27 {
  28         static int init = 0;
  29
  30         memset(mp,0,sizeof(struct mpstr));
  31
  32         mp->framesize = 0;
  33         mp->fsizeold = -1;
  34         mp->bsize = 0;
  35         mp->head = mp->tail = NULL;
  36         mp->fr.single = -1;
  37         mp->bsnum = 0;
  38         mp->synth_bo = 1;
  39         mp->fr.mp = mp;
  40
  41         if(!init) {
  42                 init = 1;
  43                 make_decode_tables(32767);
  44                 init_layer2();
  45                 init_layer3(SBLIMIT);
  46         }
  47
  48         return !0;
  49 }
  50
  51 void ExitMP3(struct mpstr *mp)
  52 {
  53         struct buf *b,*bn;
  54
  55         b = mp->tail;
  56         while(b) {
  57                 free(b->pnt);
  58                 bn = b->next;
  59                 free(b);
  60                 b = bn;
  61         }
  62 }
  63
  64 static struct buf *addbuf(struct mpstr *mp,const unsigned char *buf,int size)
  65 {
  66         struct buf *nbuf;
  67
  68         nbuf = malloc( sizeof(struct buf) );
  69         if(!nbuf) {
  70                 fprintf(stderr,"Out of memory!\n");
  71                 return NULL;
  72         }
  73         nbuf->pnt = malloc(size);
  74         if(!nbuf->pnt) {
  75                 free(nbuf);
  76                 return NULL;
  77         }
  78         nbuf->size = size;
  79         memcpy(nbuf->pnt,buf,size);
  80         nbuf->next = NULL;
  81         nbuf->prev = mp->head;
  82         nbuf->pos = 0;
  83
  84         if(!mp->tail) {
  85                 mp->tail = nbuf;
  86         }
  87         else {
  88           mp->head->next = nbuf;
  89         }
  90
  91         mp->head = nbuf;
  92         mp->bsize += size;
  93
  94         return nbuf;
  95 }
  96
  97 static void remove_buf(struct mpstr *mp)
  98 {
  99   struct buf *buf = mp->tail;
 100
 101   mp->tail = buf->next;
 102   if(mp->tail)
 103     mp->tail->prev = NULL;
 104   else {
 105     mp->tail = mp->head = NULL;
 106   }
 107
 108   free(buf->pnt);
 109   free(buf);
 110
 111 }
 112
 113 static int read_buf_byte(struct mpstr *mp)
 114 {
 115         unsigned int b;
 116
 117         int pos;
 118
 119         pos = mp->tail->pos;
 120         while(pos >= mp->tail->size) {
 121                 remove_buf(mp);
 122                 pos = mp->tail->pos;
 123         }
 124
 125         b = mp->tail->pnt[pos];
 126         mp->bsize--;
 127         mp->tail->pos++;
 128
 129
 130         return b;
 131 }
 132
 133 static void read_head(struct mpstr *mp)
 134 {
 135         unsigned long head;
 136
 137         head = read_buf_byte(mp);
 138         head <<= 8;
 139         head |= read_buf_byte(mp);
 140         head <<= 8;
 141         head |= read_buf_byte(mp);
 142         head <<= 8;
 143         head |= read_buf_byte(mp);
 144
 145         mp->header = head;
 146 }
 147
 148 int decodeMP3(struct mpstr *mp,const unsigned char *in,int isize,unsigned char *out,
 149                 int osize,int *done)
 150 {
 151         int len;
 152
 153         if(osize < 4608) {
 154                 fprintf(stderr,"To less out space\n");
 155                 return MP3_ERR;
 156         }
 157
 158         if(in) {
 159                 if(addbuf(mp,in,isize) == NULL) {
 160                         return MP3_ERR;
 161                 }
 162         }
 163
 164         /* First decode header */
 165         if(mp->framesize == 0) {
 166                 if(mp->bsize < 4) {
 167                         return MP3_NEED_MORE;
 168                 }
 169                 read_head(mp);
 170                 if (decode_header(&mp->fr,mp->header) == 0) {
 171                         return MP3_ERR;
 172                 }
 173                 mp->framesize = mp->fr.framesize;
 174         }
 175
 176         if(mp->fr.framesize > mp->bsize)
 177                 return MP3_NEED_MORE;
 178
 179         wordpointer = mp->bsspace[mp->bsnum] + 512;
 180         mp->bsnum = (mp->bsnum + 1) & 0x1;
 181         bitindex = 0;
 182
 183         len = 0;
 184         while(len < mp->framesize) {
 185                 int nlen;
 186                 int blen = mp->tail->size - mp->tail->pos;
 187                 if( (mp->framesize - len) <= blen) {
 188                   nlen = mp->framesize-len;
 189                 }
 190                 else {
 191                   nlen = blen;
 192                 }
 193                 memcpy(wordpointer+len,mp->tail->pnt+mp->tail->pos,nlen);
 194                 len += nlen;
 195                 mp->tail->pos += nlen;
 196                 mp->bsize -= nlen;
 197                 if(mp->tail->pos == mp->tail->size) {
 198                    remove_buf(mp);
 199                 }
 200         }
 201
 202         *done = 0;
 203         if(mp->fr.error_protection)
 204            getbits(16);
 205         switch(mp->fr.lay) {
 206           case 1:
 207             do_layer1(&mp->fr,out,done);
 208             break;
 209           case 2:
 210             do_layer2(&mp->fr,out,done);
 211             break;
 212           case 3:
 213             do_layer3(&mp->fr,out,done);
 214             break;
 215         }
 216
 217         mp->fsizeold = mp->framesize;
 218         mp->framesize = 0;
 219
 220         return MP3_OK;
 221 }
 222
 223 int set_pointer(struct mpstr *mp, long backstep)
 224 {
 225   unsigned char *bsbufold;
 226   if(mp->fsizeold < 0 && backstep > 0) {
 227     fprintf(stderr,"Can't step back %ld!\n",backstep);
 228     return MP3_ERR;
 229   }
 230   bsbufold = mp->bsspace[mp->bsnum] + 512;
 231   wordpointer -= backstep;
 232   if (backstep)
 233     memcpy(wordpointer,bsbufold+mp->fsizeold-backstep,backstep);
 234   bitindex = 0;
 235   return MP3_OK;
 236 }