ogg_afh.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.c Audio format handler for ogg/vorbis files. */
   8
   9 #include <vorbis/codec.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 struct private_vorbis_data {
  19         vorbis_info vi;
  20         vorbis_comment vc;
  21 };
  22
  23 static int vorbis_packet_callback(ogg_packet *packet, int packet_num,
  24                 __a_unused int serial, struct afh_info *afhi, void *private_data)
  25 {
  26         struct private_vorbis_data *pvd = private_data;
  27
  28         if (vorbis_synthesis_headerin(&pvd->vi, &pvd->vc, packet) < 0)
  29                 return -E_VORBIS;
  30         if (packet_num == 0) {
  31                 if (pvd->vi.rate == 0)
  32                         return -E_VORBIS;
  33                 afhi->channels = pvd->vi.channels;
  34                 afhi->frequency = pvd->vi.rate;
  35                 afhi->bitrate = pvd->vi.bitrate_nominal / 1000;
  36                 PARA_DEBUG_LOG("channels: %i, sampling rate: %i, bitrate: %i\n",
  37                         afhi->channels, afhi->frequency, afhi->bitrate);
  38                 return 1;
  39         }
  40         if (packet_num == 1)
  41                 return 1; /* we also want to have packet #2 */
  42         afhi->tags.artist = para_strdup(vorbis_comment_query(&pvd->vc, "artist", 0));
  43         afhi->tags.title = para_strdup(vorbis_comment_query(&pvd->vc, "title", 0));
  44         afhi->tags.album = para_strdup(vorbis_comment_query(&pvd->vc, "album", 0));
  45         afhi->tags.year = para_strdup(vorbis_comment_query(&pvd->vc, "year", 0));
  46         afhi->tags.comment = para_strdup(vorbis_comment_query(&pvd->vc, "comment", 0));
  47         return 0;
  48 }
  49
  50 static int ogg_vorbis_get_file_info(char *map, size_t numbytes, __a_unused int fd,
  51                 struct afh_info *afhi)
  52 {
  53         int ret;
  54         struct private_vorbis_data pvd;
  55         struct ogg_afh_callback_info vorbis_callback_info = {
  56                 .packet_callback = vorbis_packet_callback,
  57                 .private_data = &pvd,
  58         };
  59
  60         vorbis_info_init(&pvd.vi);
  61         vorbis_comment_init(&pvd.vc);
  62         ret = ogg_get_file_info(map, numbytes, afhi, &vorbis_callback_info);
  63         vorbis_info_clear(&pvd.vi);
  64         vorbis_comment_clear(&pvd.vc);
  65         return ret;
  66 }
  67
  68 struct vorbis_get_header_data {
  69         ogg_stream_state os;
  70         char *buf;
  71         size_t len;
  72 };
  73
  74 static void add_ogg_page(ogg_page *og, struct vorbis_get_header_data *vghd)
  75 {
  76         size_t old_len = vghd->len;
  77         size_t new_len = vghd->len + og->header_len + og->body_len;
  78         char *buf = para_realloc(vghd->buf, new_len), *p = buf + old_len;
  79
  80         memcpy(p, og->header, og->header_len);
  81         memcpy(p + og->header_len, og->body, og->body_len);
  82         vghd->buf = buf;
  83         vghd->len = new_len;
  84         PARA_DEBUG_LOG("header/body/old/new: %lu/%lu/%zu/%zu\n",
  85                 og->header_len, og->body_len, old_len, new_len);
  86 }
  87
  88 /*
  89  * Process the first three ogg packets.
  90  *
  91  * This creates chunk zero (the audio file header) from the first three ogg
  92  * packets of the input file with metadata (vorbis comments) stripped off. Page
  93  * 0 of the input file always contains only ogg packet #0 while page 1 usually
  94  * contains both packets 1 (comments) and 2 (setup).  However, we always create
  95  * an separate ogg page for each packet to circumvent a bug in older libogg
  96  * versions which causes too little data being copied to the second ogg page.
  97  * This affects at least Ubuntu Hardy, and there is no real disadvantage in
  98  * creating three pages instead of two.
  99  */
 100 static int vorbis_get_header_callback(ogg_packet *packet, int packet_num,
 101                 int serial, __a_unused struct afh_info *afhi, void *private_data)
 102 {
 103         int ret;
 104         struct vorbis_get_header_data *vghd = private_data;
 105         ogg_page og;
 106         static unsigned char dummy_packet[] = {
 107                 0x03,
 108                 'v', 'o', 'r', 'b', 'i', 's',
 109                 0x06, 0x00, 0x00, 0x00,
 110                 'd', 'u', 'm', 'm', 'y', '\0',
 111                 0x00, 0x00, 0x00, 0x00, /* no comment :) */
 112                 0xff /* framing bit */
 113         };
 114
 115         PARA_DEBUG_LOG("processing ogg packet #%d (%li bytes)\n",
 116                 packet_num, packet->bytes);
 117         if (packet_num > 2)
 118                 return 0;
 119         if (packet_num == 0) {
 120                 ogg_stream_init(&vghd->os, serial);
 121                 ret = -E_OGG_PACKET_IN;
 122                 ret = ogg_stream_packetin(&vghd->os, packet);
 123                 if (ret < 0)
 124                         goto out;
 125                 ret = -E_OGG_STREAM_FLUSH;
 126                 if (ogg_stream_flush(&vghd->os, &og) == 0)
 127                         goto out;
 128                 add_ogg_page(&og, vghd);
 129                 return 1;
 130         }
 131         if (packet_num == 1) {
 132                 PARA_INFO_LOG("replacing metadata packet (saved %ld bytes)\n",
 133                         packet->bytes - sizeof(dummy_packet));
 134                 ogg_packet replacement = *packet;
 135                 replacement.packet = dummy_packet;
 136                 replacement.bytes = sizeof(dummy_packet);
 137                 ret = -E_OGG_PACKET_IN;
 138                 if (ogg_stream_packetin(&vghd->os, &replacement) < 0)
 139                         goto out;
 140                 ret = -E_OGG_STREAM_FLUSH;
 141                 if (ogg_stream_flush(&vghd->os, &og) == 0)
 142                         goto out;
 143                 add_ogg_page(&og, vghd);
 144                 return 1;
 145         }
 146         ret = -E_OGG_PACKET_IN;
 147         if (ogg_stream_packetin(&vghd->os, packet) < 0)
 148                 goto out;
 149         ret = -E_OGG_STREAM_FLUSH;
 150         if (ogg_stream_flush(&vghd->os, &og) == 0)
 151                 goto out;
 152         add_ogg_page(&og, vghd);
 153         ret = 0;
 154 out:
 155         ogg_stream_clear(&vghd->os);
 156         return ret;
 157 }
 158
 159 static void vorbis_get_header(void *map, size_t mapsize, char **buf,
 160                 size_t *len)
 161 {
 162         int ret;
 163         struct vorbis_get_header_data vghd = {.len = 0};
 164         struct ogg_afh_callback_info cb = {
 165                 .packet_callback = vorbis_get_header_callback,
 166                 .private_data = &vghd,
 167         };
 168
 169         ret = ogg_get_file_info(map, mapsize, NULL, &cb);
 170         if (ret < 0)
 171                 goto fail;
 172         *buf = vghd.buf;
 173         *len = vghd.len;
 174         PARA_INFO_LOG("created %zu byte ogg/vorbis header chunk\n", *len);
 175         return;
 176 fail:
 177         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 178 }
 179
 180 static const char* ogg_suffixes[] = {"ogg", NULL};
 181
 182 /**
 183  * The init function of the ogg vorbis audio format handler.
 184  *
 185  * \param afh Pointer to the struct to initialize.
 186  */
 187 void ogg_init(struct audio_format_handler *afh)
 188 {
 189         afh->get_file_info = ogg_vorbis_get_file_info;
 190         afh->get_header = vorbis_get_header;
 191         afh->suffixes = ogg_suffixes;
 192 }