src/libFLAC/ogg_encoder_aspect.c

   1 /* libFLAC - Free Lossless Audio Codec
   2  * Copyright (C) 2002-2009  Josh Coalson
   3  * Copyright (C) 2011-2013  Xiph.Org Foundation
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  *
  12  * - Redistributions in binary form must reproduce the above copyright
  13  * notice, this list of conditions and the following disclaimer in the
  14  * documentation and/or other materials provided with the distribution.
  15  *
  16  * - Neither the name of the Xiph.org Foundation nor the names of its
  17  * contributors may be used to endorse or promote products derived from
  18  * this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
  24  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  25  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  26  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  27  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  28  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  29  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  30  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #if HAVE_CONFIG_H
  34 #  include <config.h>
  35 #endif
  36
  37 #include <string.h> /* for memset() */
  38 #include "FLAC/assert.h"
  39 #include "private/ogg_encoder_aspect.h"
  40 #include "private/ogg_mapping.h"
  41
  42 static const FLAC__byte FLAC__OGG_MAPPING_VERSION_MAJOR = 1;
  43 static const FLAC__byte FLAC__OGG_MAPPING_VERSION_MINOR = 0;
  44
  45 /***********************************************************************
  46  *
  47  * Public class methods
  48  *
  49  ***********************************************************************/
  50
  51 FLAC__bool FLAC__ogg_encoder_aspect_init(FLAC__OggEncoderAspect *aspect)
  52 {
  53         /* we will determine the serial number later if necessary */
  54         if(ogg_stream_init(&aspect->stream_state, aspect->serial_number) != 0)
  55                 return false;
  56
  57         aspect->seen_magic = false;
  58         aspect->is_first_packet = true;
  59         aspect->samples_written = 0;
  60
  61         return true;
  62 }
  63
  64 void FLAC__ogg_encoder_aspect_finish(FLAC__OggEncoderAspect *aspect)
  65 {
  66         (void)ogg_stream_clear(&aspect->stream_state);
  67         /*@@@ what about the page? */
  68 }
  69
  70 void FLAC__ogg_encoder_aspect_set_serial_number(FLAC__OggEncoderAspect *aspect, long value)
  71 {
  72         aspect->serial_number = value;
  73 }
  74
  75 FLAC__bool FLAC__ogg_encoder_aspect_set_num_metadata(FLAC__OggEncoderAspect *aspect, unsigned value)
  76 {
  77         if(value < (1u << FLAC__OGG_MAPPING_NUM_HEADERS_LEN)) {
  78                 aspect->num_metadata = value;
  79                 return true;
  80         }
  81         else
  82                 return false;
  83 }
  84
  85 void FLAC__ogg_encoder_aspect_set_defaults(FLAC__OggEncoderAspect *aspect)
  86 {
  87         aspect->serial_number = 0;
  88         aspect->num_metadata = 0;
  89 }
  90
  91 /*
  92  * The basic FLAC -> Ogg mapping goes like this:
  93  *
  94  * - 'fLaC' magic and STREAMINFO block get combined into the first
  95  *   packet.  The packet is prefixed with
  96  *   + the one-byte packet type 0x7F
  97  *   + 'FLAC' magic
  98  *   + the 2 byte Ogg FLAC mapping version number
  99  *   + tne 2 byte big-endian # of header packets
 100  * - The first packet is flushed to the first page.
 101  * - Each subsequent metadata block goes into its own packet.
 102  * - Each metadata packet is flushed to page (this is not required,
 103  *   the mapping only requires that a flush must occur after all
 104  *   metadata is written).
 105  * - Each subsequent FLAC audio frame goes into its own packet.
 106  *
 107  * WATCHOUT:
 108  * This depends on the behavior of FLAC__StreamEncoder that we get a
 109  * separate write callback for the fLaC magic, and then separate write
 110  * callbacks for each metadata block and audio frame.
 111  */
 112 FLAC__StreamEncoderWriteStatus FLAC__ogg_encoder_aspect_write_callback_wrapper(FLAC__OggEncoderAspect *aspect, const FLAC__byte buffer[], size_t bytes, unsigned samples, unsigned current_frame, FLAC__bool is_last_block, FLAC__OggEncoderAspectWriteCallbackProxy write_callback, void *encoder, void *client_data)
 113 {
 114         /* WATCHOUT:
 115          * This depends on the behavior of FLAC__StreamEncoder that 'samples'
 116          * will be 0 for metadata writes.
 117          */
 118         const FLAC__bool is_metadata = (samples == 0);
 119
 120         /*
 121          * Treat fLaC magic packet specially.  We will note when we see it, then
 122          * wait until we get the STREAMINFO and prepend it in that packet
 123          */
 124         if(aspect->seen_magic) {
 125                 ogg_packet packet;
 126                 FLAC__byte synthetic_first_packet_body[
 127                         FLAC__OGG_MAPPING_PACKET_TYPE_LENGTH +
 128                         FLAC__OGG_MAPPING_MAGIC_LENGTH +
 129                         FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH +
 130                         FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH +
 131                         FLAC__OGG_MAPPING_NUM_HEADERS_LENGTH +
 132                         FLAC__STREAM_SYNC_LENGTH +
 133                         FLAC__STREAM_METADATA_HEADER_LENGTH +
 134                         FLAC__STREAM_METADATA_STREAMINFO_LENGTH
 135                 ];
 136
 137                 memset(&packet, 0, sizeof(packet));
 138                 packet.granulepos = aspect->samples_written + samples;
 139
 140                 if(aspect->is_first_packet) {
 141                         FLAC__byte *b = synthetic_first_packet_body;
 142                         if(bytes != FLAC__STREAM_METADATA_HEADER_LENGTH + FLAC__STREAM_METADATA_STREAMINFO_LENGTH) {
 143                                 /*
 144                                  * If we get here, our assumption about the way write callbacks happen
 145                                  * (explained above) is wrong
 146                                  */
 147                                 FLAC__ASSERT(0);
 148                                 return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 149                         }
 150                         /* add first header packet type */
 151                         *b = FLAC__OGG_MAPPING_FIRST_HEADER_PACKET_TYPE;
 152                         b += FLAC__OGG_MAPPING_PACKET_TYPE_LENGTH;
 153                         /* add 'FLAC' mapping magic */
 154                         memcpy(b, FLAC__OGG_MAPPING_MAGIC, FLAC__OGG_MAPPING_MAGIC_LENGTH);
 155                         b += FLAC__OGG_MAPPING_MAGIC_LENGTH;
 156                         /* add Ogg FLAC mapping major version number */
 157                         memcpy(b, &FLAC__OGG_MAPPING_VERSION_MAJOR, FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH);
 158                         b += FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH;
 159                         /* add Ogg FLAC mapping minor version number */
 160                         memcpy(b, &FLAC__OGG_MAPPING_VERSION_MINOR, FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH);
 161                         b += FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH;
 162                         /* add number of header packets */
 163                         *b = (FLAC__byte)(aspect->num_metadata >> 8);
 164                         b++;
 165                         *b = (FLAC__byte)(aspect->num_metadata);
 166                         b++;
 167                         /* add native FLAC 'fLaC' magic */
 168                         memcpy(b, FLAC__STREAM_SYNC_STRING, FLAC__STREAM_SYNC_LENGTH);
 169                         b += FLAC__STREAM_SYNC_LENGTH;
 170                         /* add STREAMINFO */
 171                         memcpy(b, buffer, bytes);
 172                         FLAC__ASSERT(b + bytes - synthetic_first_packet_body == sizeof(synthetic_first_packet_body));
 173                         packet.packet = (unsigned char *)synthetic_first_packet_body;
 174                         packet.bytes = sizeof(synthetic_first_packet_body);
 175
 176                         packet.b_o_s = 1;
 177                         aspect->is_first_packet = false;
 178                 }
 179                 else {
 180                         packet.packet = (unsigned char *)buffer;
 181                         packet.bytes = bytes;
 182                 }
 183
 184                 if(is_last_block) {
 185                         /* we used to check:
 186                          * FLAC__ASSERT(total_samples_estimate == 0 || total_samples_estimate == aspect->samples_written + samples);
 187                          * but it's really not useful since total_samples_estimate is an estimate and can be inexact
 188                          */
 189                         packet.e_o_s = 1;
 190                 }
 191
 192                 if(ogg_stream_packetin(&aspect->stream_state, &packet) != 0)
 193                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 194
 195                 /*@@@ can't figure out a way to pass a useful number for 'samples' to the write_callback, so we'll just pass 0 */
 196                 if(is_metadata) {
 197                         while(ogg_stream_flush(&aspect->stream_state, &aspect->page) != 0) {
 198                                 if(write_callback(encoder, aspect->page.header, aspect->page.header_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 199                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 200                                 if(write_callback(encoder, aspect->page.body, aspect->page.body_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 201                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 202                         }
 203                 }
 204                 else {
 205                         while(ogg_stream_pageout(&aspect->stream_state, &aspect->page) != 0) {
 206                                 if(write_callback(encoder, aspect->page.header, aspect->page.header_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 207                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 208                                 if(write_callback(encoder, aspect->page.body, aspect->page.body_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 209                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 210                         }
 211                 }
 212         }
 213         else if(is_metadata && current_frame == 0 && samples == 0 && bytes == 4 && 0 == memcmp(buffer, FLAC__STREAM_SYNC_STRING, sizeof(FLAC__STREAM_SYNC_STRING))) {
 214                 aspect->seen_magic = true;
 215         }
 216         else {
 217                 /*
 218                  * If we get here, our assumption about the way write callbacks happen
 219                  * explained above is wrong
 220                  */
 221                 FLAC__ASSERT(0);
 222                 return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 223         }
 224
 225         aspect->samples_written += samples;
 226
 227         return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
 228 }