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 num_frames, int num_chunks, int frequency,
  95                 struct timeval *result)
  96 {
  97         uint64_t x = (uint64_t)num_frames * 1000 * 1000
  98                 / frequency / num_chunks;
  99
 100         result->tv_sec = x / 1000 / 1000;
 101         result->tv_usec = x % (1000 * 1000);
 102         PARA_INFO_LOG("%d chunks, chunk time: %lums\n", num_chunks,
 103                 tv2ms(result));
 104 }
 105
 106 /**
 107  * Pass first three ogg packets to callback and build the chunk table.
 108  *
 109  * This function extracts the first three ogg packets of the audio data
 110  * given by \a map and \a numbytes and passes each packet to the callback
 111  * defined by \a ci.
 112  *
 113  * If the packet callback indicates success, the chunk table is built.  Chunk
 114  * zero contains the first three ogg packets while all other chunks consist of
 115  * exactly one ogg page.
 116  *
 117  * \param map Audio file data.
 118  * \param numbytes The length of \a map.
 119  * \param afhi Passed to the packet callback, contains chunk table.
 120  * \param ci The callback structure.
 121  *
 122  * \return Standard.
 123  */
 124 int ogg_get_file_info(char *map, size_t numbytes, struct afh_info *afhi,
 125                 struct ogg_afh_callback_info *ci)
 126 {
 127         ogg_sync_state oss;
 128         ogg_page op;
 129         long len = numbytes;
 130         char *buf;
 131         int ret, i, j, frames_per_chunk, ct_size;
 132         long long unsigned num_frames = 0;
 133
 134         ogg_sync_init(&oss);
 135         ret = -E_OGG_SYNC;
 136         buf = ogg_sync_buffer(&oss, len);
 137         if (!buf)
 138                 goto out;
 139         memcpy(buf, map, len);
 140         ret = -E_OGG_SYNC;
 141         if (ogg_sync_wrote(&oss, len) < 0)
 142                 goto out;
 143         ret = process_ogg_packets(&oss, afhi, ci);
 144         if (ret < 0)
 145                 goto out;
 146         oss.returned = 0;
 147         oss.fill = numbytes;
 148         /* count ogg pages and get duration of the file */
 149         for (i = 0; ogg_sync_pageseek(&oss, &op) > 0; i++)
 150                 num_frames = ogg_page_granulepos(&op);
 151         PARA_INFO_LOG("%d pages, %llu frames\n", i, num_frames);
 152         ret = -E_OGG_EMPTY;
 153         if (i == 0)
 154                 goto out;
 155         afhi->seconds_total = num_frames / afhi->frequency;
 156         /* use roughly one page per chunk */
 157         frames_per_chunk = num_frames / i;
 158         PARA_INFO_LOG("%lu seconds, %d frames/chunk\n",
 159                 afhi->seconds_total, frames_per_chunk);
 160         ct_size = 250;
 161         afhi->chunk_table = para_malloc(ct_size * sizeof(uint32_t));
 162         afhi->chunk_table[0] = 0;
 163         afhi->chunk_table[1] = afhi->header_len;
 164         oss.returned = afhi->header_len;
 165         oss.fill = numbytes;
 166         for (j = 1; ogg_sync_pageseek(&oss, &op) > 0; /* nothing */) {
 167                 int granule = ogg_page_granulepos(&op);
 168
 169                 while (granule > j * frames_per_chunk) {
 170                         j++;
 171                         if (j >= ct_size) {
 172                                 ct_size *= 2;
 173                                 afhi->chunk_table = para_realloc(
 174                                         afhi->chunk_table,
 175                                         ct_size * sizeof(uint32_t));
 176                         }
 177                         afhi->chunk_table[j] = oss.returned;
 178                 }
 179         }
 180         afhi->chunks_total = j;
 181         set_chunk_tv(num_frames, j, afhi->frequency, &afhi->chunk_tv);
 182         ret = 0;
 183 out:
 184         ogg_sync_clear(&oss);
 185         return ret;
 186 }