ogg_afh_common.c

   1 /*
   2  * Copyright (C) 2004-2010 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         ret = -E_SYNC_PAGEOUT;
  68         if (ogg_sync_pageout(oss, &page) != 1)
  69                 goto out;
  70
  71         ret = ogg_page_serialno(&page);
  72         ogg_stream_init(&stream, ret);
  73
  74         ret = -E_STREAM_PAGEIN;
  75         if (ogg_stream_pagein(&stream, &page) < 0)
  76                 goto out;
  77
  78         ret = -E_STREAM_PACKETOUT;
  79         if (ogg_stream_packetout(&stream, &packet) != 1)
  80                 goto out;
  81         ret = ci->packet_callback(&packet, 0, afhi, ci->private_data);
  82         if (ret < 0)
  83                 goto out;
  84         ret = process_packets_2_and_3(oss, &stream, afhi, ci);
  85         if (ret < 0)
  86                 goto out;
  87         afhi->header_offset = 0;
  88         afhi->header_len = oss->returned;
  89         ret = 1;
  90 out:
  91         ogg_stream_clear(&stream);
  92         return ret;
  93 }
  94
  95 static void set_chunk_tv(int num_frames, int num_chunks, int frequency,
  96                 struct timeval *result)
  97 {
  98         uint64_t x = (uint64_t)num_frames * 1000 * 1000
  99                 / frequency / num_chunks;
 100
 101         result->tv_sec = x / 1000 / 1000;
 102         result->tv_usec = x % (1000 * 1000);
 103         PARA_INFO_LOG("%d chunks, chunk time: %lums\n", num_chunks,
 104                 tv2ms(result));
 105 }
 106
 107 /**
 108  * Pass first three ogg packets to callback and build the chunk table.
 109  *
 110  * This function extracts the first three ogg packets of the audio data
 111  * given by \a map and \a numbytes and passes each packet to the callback
 112  * defined by \a ci.
 113  *
 114  * If the packet callback indicates success, the chunk table is built.  Chunk
 115  * zero contains the first three ogg packets while all other chunks consist of
 116  * exactly one ogg page.
 117  *
 118  * \param map Audio file data.
 119  * \param numbytes The length of \a map.
 120  * \param afhi Passed to the packet callback, contains chunk table.
 121  * \param ci The callback structure.
 122  *
 123  * \return Standard.
 124  */
 125 int ogg_get_file_info(char *map, size_t numbytes, struct afh_info *afhi,
 126                 struct ogg_afh_callback_info *ci)
 127 {
 128         ogg_sync_state oss;
 129         ogg_page op;
 130         long len = numbytes;
 131         char *buf;
 132         int ret, i, j, frames_per_chunk, ct_size;
 133         long long unsigned num_frames = 0;
 134
 135         ogg_sync_init(&oss);
 136         ret = -E_OGG_SYNC;
 137         buf = ogg_sync_buffer(&oss, len);
 138         if (!buf)
 139                 goto out;
 140         memcpy(buf, map, len);
 141         ret = -E_OGG_SYNC;
 142         if (ogg_sync_wrote(&oss, len) < 0)
 143                 goto out;
 144         ret = process_ogg_packets(&oss, afhi, ci);
 145         if (ret < 0)
 146                 goto out;
 147         oss.returned = 0;
 148         oss.fill = numbytes;
 149         /* count ogg packages and get duration of the file */
 150         for (i = 0; ogg_sync_pageseek(&oss, &op) > 0; i++)
 151                 num_frames = ogg_page_granulepos(&op);
 152         PARA_INFO_LOG("%d pages, %llu frames\n", i, num_frames);
 153         ret = -E_OGG_EMPTY;
 154         if (i == 0)
 155                 goto out;
 156         afhi->seconds_total = num_frames / afhi->frequency;
 157         /* use roughly one page per chunk */
 158         frames_per_chunk = num_frames / i;
 159         PARA_INFO_LOG("%lu seconds, %d frames/chunk\n",
 160                 afhi->seconds_total, frames_per_chunk);
 161         ct_size = 250;
 162         afhi->chunk_table = para_malloc(ct_size * sizeof(uint32_t));
 163         afhi->chunk_table[0] = 0;
 164         afhi->chunk_table[1] = afhi->header_len;
 165         oss.returned = afhi->header_len;
 166         oss.fill = numbytes;
 167         for (i = 0, j = 1; ogg_sync_pageseek(&oss, &op) > 0; i++) {
 168                 int granule = ogg_page_granulepos(&op);
 169
 170                 while (granule > j * frames_per_chunk) {
 171                         j++;
 172                         if (j >= ct_size) {
 173                                 ct_size *= 2;
 174                                 afhi->chunk_table = para_realloc(
 175                                         afhi->chunk_table,
 176                                         ct_size * sizeof(uint32_t));
 177                         }
 178                         afhi->chunk_table[j] = oss.returned;
 179                 }
 180         }
 181         afhi->chunks_total = j;
 182         set_chunk_tv(num_frames, j, afhi->frequency, &afhi->chunk_tv);
 183         ret = 0;
 184 out:
 185         ogg_sync_clear(&oss);
 186         return ret;
 187 }