ogg_afh_common.c

   1 /*
   2  * Copyright (C) 2004-2011 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file ogg_afh_common.c Functions common to ogg/vorbis and ogg/speex. */
   8
   9 #include <ogg/ogg.h>
  10 #include <regex.h>
  11
  12 #include "para.h"
  13 #include "afh.h"
  14 #include "error.h"
  15 #include "string.h"
  16 #include "ogg_afh_common.h"
  17
  18
  19 /* Taken from decoder_example.c of libvorbis-1.2.3. */
  20 static int process_packets_2_and_3(ogg_sync_state *oss,
  21                 ogg_stream_state *stream, struct afh_info *afhi,
  22                 struct ogg_afh_callback_info *ci)
  23 {
  24         ogg_page page;
  25         ogg_packet packet;
  26         int i = 0;
  27
  28         while (i < 2) {
  29                 while (i < 2) {
  30                         int ret = ogg_sync_pageout(oss, &page);
  31                         if (ret == 0)
  32                                 break; /* Need more data */
  33                         if (ret != 1)
  34                                 continue;
  35                         /*
  36                          * We can ignore any errors here as they'll also become
  37                          * apparent at packetout.
  38                          */
  39                         ogg_stream_pagein(stream, &page);
  40                         while (i < 2) {
  41                                 ret = ogg_stream_packetout(stream, &packet);
  42                                 if (ret == 0)
  43                                         break;
  44                                 if (ret < 0)
  45                                         return -E_STREAM_PACKETOUT;
  46                                 ret = ci->packet_callback(&packet, i + 1, afhi,
  47                                         ci->private_data);
  48                                 if (ret < 0)
  49                                         return ret;
  50                                 if (ret == 0) /* header complete */
  51                                         return 1;
  52                                 i++;
  53                         }
  54                 }
  55         }
  56         return 1;
  57 }
  58
  59 static int process_ogg_packets(ogg_sync_state *oss, struct afh_info *afhi,
  60                 struct ogg_afh_callback_info *ci)
  61 {
  62         ogg_packet packet;
  63         ogg_stream_state stream;
  64         ogg_page page;
  65         int ret;
  66
  67         if (ogg_sync_pageout(oss, &page) != 1)
  68                 return -E_SYNC_PAGEOUT;
  69
  70         ret = ogg_page_serialno(&page);
  71         ogg_stream_init(&stream, ret);
  72
  73         ret = -E_STREAM_PAGEIN;
  74         if (ogg_stream_pagein(&stream, &page) < 0)
  75                 goto out;
  76
  77         ret = -E_STREAM_PACKETOUT;
  78         if (ogg_stream_packetout(&stream, &packet) != 1)
  79                 goto out;
  80         ret = ci->packet_callback(&packet, 0, afhi, ci->private_data);
  81         if (ret < 0)
  82                 goto out;
  83         ret = process_packets_2_and_3(oss, &stream, afhi, ci);
  84         if (ret < 0)
  85                 goto out;
  86         afhi->header_offset = 0;
  87         afhi->header_len = oss->returned;
  88         ret = 1;
  89 out:
  90         ogg_stream_clear(&stream);
  91         return ret;
  92 }
  93
  94 static void set_chunk_tv(int frames_per_chunk, int frequency,
  95                 struct timeval *result)
  96 {
  97         uint64_t x = (uint64_t)frames_per_chunk * 1000 * 1000 / frequency;
  98
  99         result->tv_sec = x / 1000 / 1000;
 100         result->tv_usec = x % (1000 * 1000);
 101         PARA_INFO_LOG("%d frames per chunk, chunk time: %lums\n",
 102                 frames_per_chunk, tv2ms(result));
 103 }
 104
 105 /**
 106  * Pass first three ogg packets to callback and build the chunk table.
 107  *
 108  * This function extracts the first three ogg packets of the audio data
 109  * given by \a map and \a numbytes and passes each packet to the callback
 110  * defined by \a ci.
 111  *
 112  * If the packet callback indicates success, the chunk table is built.  Chunk
 113  * zero contains the first three ogg packets while all other chunks consist of
 114  * exactly one ogg page.
 115  *
 116  * \param map Audio file data.
 117  * \param numbytes The length of \a map.
 118  * \param afhi Passed to the packet callback, contains chunk table.
 119  * \param ci The callback structure.
 120  *
 121  * \return Standard.
 122  */
 123 int ogg_get_file_info(char *map, size_t numbytes, struct afh_info *afhi,
 124                 struct ogg_afh_callback_info *ci)
 125 {
 126         ogg_sync_state oss;
 127         ogg_page op;
 128         long len = numbytes;
 129         char *buf;
 130         int ret, i, j, frames_per_chunk, ct_size;
 131         long long unsigned num_frames = 0;
 132
 133         ogg_sync_init(&oss);
 134         ret = -E_OGG_SYNC;
 135         buf = ogg_sync_buffer(&oss, len);
 136         if (!buf)
 137                 goto out;
 138         memcpy(buf, map, len);
 139         ret = -E_OGG_SYNC;
 140         if (ogg_sync_wrote(&oss, len) < 0)
 141                 goto out;
 142         ret = process_ogg_packets(&oss, afhi, ci);
 143         if (ret < 0)
 144                 goto out;
 145         oss.returned = 0;
 146         oss.fill = numbytes;
 147         /* count ogg pages and get duration of the file */
 148         for (i = 0; ogg_sync_pageseek(&oss, &op) > 0; i++)
 149                 num_frames = ogg_page_granulepos(&op);
 150         PARA_INFO_LOG("%d pages, %llu frames\n", i, num_frames);
 151         ret = -E_OGG_EMPTY;
 152         if (i == 0)
 153                 goto out;
 154         afhi->seconds_total = num_frames / afhi->frequency;
 155         /* use roughly one page per chunk */
 156         frames_per_chunk = num_frames / i;
 157         PARA_INFO_LOG("%lu seconds, %d frames/chunk\n",
 158                 afhi->seconds_total, frames_per_chunk);
 159         ct_size = 250;
 160         afhi->chunk_table = para_malloc(ct_size * sizeof(uint32_t));
 161         afhi->chunk_table[0] = 0;
 162         afhi->chunk_table[1] = afhi->header_len;
 163         oss.returned = afhi->header_len;
 164         oss.fill = numbytes;
 165         for (j = 1; ogg_sync_pageseek(&oss, &op) > 0; /* nothing */) {
 166                 int granule = ogg_page_granulepos(&op);
 167
 168                 while (granule > j * frames_per_chunk) {
 169                         j++;
 170                         if (j >= ct_size) {
 171                                 ct_size *= 2;
 172                                 afhi->chunk_table = para_realloc(
 173                                         afhi->chunk_table,
 174                                         ct_size * sizeof(uint32_t));
 175                         }
 176                         afhi->chunk_table[j] = oss.returned;
 177                 }
 178         }
 179         afhi->chunks_total = j;
 180         set_chunk_tv(frames_per_chunk, afhi->frequency, &afhi->chunk_tv);
 181         ret = 0;
 182 out:
 183         ogg_sync_clear(&oss);
 184         return ret;
 185 }