/* libSoX MP3 utilities  Copyright (c) 2007-9 SoX contributors * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or (at * your option) any later version. * * This library 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 Lesser * General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA */ #include <sys/stat.h> #if defined(HAVE_LAME) static void write_comments(sox_format_t * ft){  priv_t *p = (priv_t *) ft->priv;  const char* comment;   p->id3tag_init(p->gfp);  p->id3tag_set_pad(p->gfp, (size_t)ID3PADDING);   /* Note: id3tag_set_fieldvalue is not present in LAME 3.97, so we're using     the 3.97-compatible methods for all of the tags that 3.97 supported. */  /* FIXME: This is no more necessary, since support for LAME 3.97 has ended. */  if ((comment = sox_find_comment(ft->oob.comments, "Title")))    p->id3tag_set_title(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Artist")))    p->id3tag_set_artist(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Album")))    p->id3tag_set_album(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Tracknumber")))    p->id3tag_set_track(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Year")))    p->id3tag_set_year(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Comment")))    p->id3tag_set_comment(p->gfp, comment);  if ((comment = sox_find_comment(ft->oob.comments, "Genre")))  {    if (p->id3tag_set_genre(p->gfp, comment))      lsx_warn("\"%s\" is not a recognized ID3v1 genre.", comment);  }   if ((comment = sox_find_comment(ft->oob.comments, "Discnumber")))  {    char* id3tag_buf = lsx_malloc(strlen(comment) + 6);    if (id3tag_buf)    {      sprintf(id3tag_buf, "TPOS=%s", comment);      p->id3tag_set_fieldvalue(p->gfp, id3tag_buf);      free(id3tag_buf);    }  }} #endif /* HAVE_LAME */ #ifdef HAVE_MAD_H static unsigned long xing_frames(priv_t * p, struct mad_bitptr ptr, unsigned bitlen){  #define XING_MAGIC ( ('X' << 24) | ('i' << 16) | ('n' << 8) | 'g' )  if (bitlen >= 96 && p->mad_bit_read(&ptr, 32) == XING_MAGIC &&      (p->mad_bit_read(&ptr, 32) & 1 )) /* XING_FRAMES */    return p->mad_bit_read(&ptr, 32);  return 0;} static size_t mp3_duration(sox_format_t * ft){  priv_t              * p = (priv_t *) ft->priv;  struct mad_stream   mad_stream;  struct mad_header   mad_header;  struct mad_frame    mad_frame;  size_t              initial_bitrate = 0; /* Initialised to prevent warning */  size_t              tagsize = 0, consumed = 0, frames = 0;  sox_bool            vbr = sox_false, depadded = sox_false;  size_t              num_samples = 0;   p->mad_stream_init(&mad_stream);  p->mad_header_init(&mad_header);  p->mad_frame_init(&mad_frame);   do {  /* Read data from the MP3 file */    int read, padding = 0;    size_t leftover = mad_stream.bufend - mad_stream.next_frame;     memmove(p->mp3_buffer, mad_stream.this_frame, leftover);    read = lsx_readbuf(ft, p->mp3_buffer + leftover, p->mp3_buffer_size - leftover);    if (read <= 0) {      lsx_debug("got exact duration by scan to EOF (frames=%" PRIuPTR " leftover=%" PRIuPTR ")", frames, leftover);      break;    }    for (; !depadded && padding < read && !p->mp3_buffer[padding]; ++padding);    depadded = sox_true;    p->mad_stream_buffer(&mad_stream, p->mp3_buffer + padding, leftover + read - padding);     while (sox_true) {  /* Decode frame headers */      mad_stream.error = MAD_ERROR_NONE;      if (p->mad_header_decode(&mad_header, &mad_stream) == -1) {        if (mad_stream.error == MAD_ERROR_BUFLEN)          break;  /* Normal behaviour; get some more data from the file */        if (!MAD_RECOVERABLE(mad_stream.error)) {          lsx_warn("unrecoverable MAD error");          break;        }        if (mad_stream.error == MAD_ERROR_LOSTSYNC) {          unsigned available = (mad_stream.bufend - mad_stream.this_frame);          tagsize = tagtype(mad_stream.this_frame, (size_t) available);          if (tagsize) {   /* It's some ID3 tags, so just skip */            if (tagsize >= available) {              lsx_seeki(ft, (off_t)(tagsize - available), SEEK_CUR);              depadded = sox_false;            }            p->mad_stream_skip(&mad_stream, min(tagsize, available));          }          else lsx_warn("MAD lost sync");        }        else lsx_warn("recoverable MAD error");        continue; /* Not an audio frame */      }       num_samples += MAD_NSBSAMPLES(&mad_header) * 32;      consumed += mad_stream.next_frame - mad_stream.this_frame;       lsx_debug_more("bitrate=%lu", mad_header.bitrate);      if (!frames) {        initial_bitrate = mad_header.bitrate;         /* Get the precise frame count from the XING header if present */        mad_frame.header = mad_header;        if (p->mad_frame_decode(&mad_frame, &mad_stream) == -1)          if (!MAD_RECOVERABLE(mad_stream.error)) {            lsx_warn("unrecoverable MAD error");            break;          }        if ((frames = xing_frames(p, mad_stream.anc_ptr, mad_stream.anc_bitlen))) {          num_samples *= frames;          lsx_debug("got exact duration from XING frame count (%" PRIuPTR ")", frames);          break;        }      }      else vbr |= mad_header.bitrate != initial_bitrate;       /* If not VBR, we can time just a few frames then extrapolate */      if (++frames == 25 && !vbr) {        double frame_size = (double) consumed / frames;        size_t num_frames = (lsx_filelength(ft) - tagsize) / frame_size;        num_samples = num_samples / frames * num_frames;        lsx_debug("got approx. duration by CBR extrapolation");        break;      }    }  } while (mad_stream.error == MAD_ERROR_BUFLEN);   p->mad_frame_finish(&mad_frame);  mad_header_finish(&mad_header);  p->mad_stream_finish(&mad_stream);  lsx_rewind(ft);   return num_samples;} #endif /* HAVE_MAD_H */