src/lib/doslib/ext/flac/ogg_encoder_aspect.c

   1 /* libFLAC - Free Lossless Audio Codec
   2  * Copyright (C) 2002,2003,2004,2005,2006,2007  Josh Coalson
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  * - Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *
  11  * - Redistributions in binary form must reproduce the above copyright
  12  * notice, this list of conditions and the following disclaimer in the
  13  * documentation and/or other materials provided with the distribution.
  14  *
  15  * - Neither the name of the Xiph.org Foundation nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
  23  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  24  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  25  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  26  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  27  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  28  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #if HAVE_CONFIG_H
  33 #  include "config.h"
  34 #endif
  35
  36 #include <string.h> /* for memset() */
  37 #include "flac/assert.h"
  38 #include "private/ogg_encoder_aspect.h"
  39 #include "private/ogg_mapping.h"
  40
  41 static const FLAC__byte FLAC__OGG_MAPPING_VERSION_MAJOR = 1;
  42 static const FLAC__byte FLAC__OGG_MAPPING_VERSION_MINOR = 0;
  43
  44 /***********************************************************************
  45  *
  46  * Public class methods
  47  *
  48  ***********************************************************************/
  49
  50 FLAC__bool FLAC__ogg_encoder_aspect_init(FLAC__OggEncoderAspect *aspect)
  51 {
  52         /* we will determine the serial number later if necessary */
  53         if(ogg_stream_init(&aspect->stream_state, aspect->serial_number) != 0)
  54                 return false;
  55
  56         aspect->seen_magic = false;
  57         aspect->is_first_packet = true;
  58         aspect->samples_written = 0;
  59
  60         return true;
  61 }
  62
  63 void FLAC__ogg_encoder_aspect_finish(FLAC__OggEncoderAspect *aspect)
  64 {
  65         (void)ogg_stream_clear(&aspect->stream_state);
  66         /*@@@ what about the page? */
  67 }
  68
  69 void FLAC__ogg_encoder_aspect_set_serial_number(FLAC__OggEncoderAspect *aspect, long value)
  70 {
  71         aspect->serial_number = value;
  72 }
  73
  74 FLAC__bool FLAC__ogg_encoder_aspect_set_num_metadata(FLAC__OggEncoderAspect *aspect, unsigned value)
  75 {
  76         if(value < (1u << FLAC__OGG_MAPPING_NUM_HEADERS_LEN)) {
  77                 aspect->num_metadata = value;
  78                 return true;
  79         }
  80         else
  81                 return false;
  82 }
  83
  84 void FLAC__ogg_encoder_aspect_set_defaults(FLAC__OggEncoderAspect *aspect)
  85 {
  86         aspect->serial_number = 0;
  87         aspect->num_metadata = 0;
  88 }
  89
  90 /*
  91  * The basic FLAC -> Ogg mapping goes like this:
  92  *
  93  * - 'fLaC' magic and STREAMINFO block get combined into the first
  94  *   packet.  The packet is prefixed with
  95  *   + the one-byte packet type 0x7F
  96  *   + 'FLAC' magic
  97  *   + the 2 byte Ogg FLAC mapping version number
  98  *   + tne 2 byte big-endian # of header packets
  99  * - The first packet is flushed to the first page.
 100  * - Each subsequent metadata block goes into its own packet.
 101  * - Each metadata packet is flushed to page (this is not required,
 102  *   the mapping only requires that a flush must occur after all
 103  *   metadata is written).
 104  * - Each subsequent FLAC audio frame goes into its own packet.
 105  *
 106  * WATCHOUT:
 107  * This depends on the behavior of FLAC__StreamEncoder that we get a
 108  * separate write callback for the fLaC magic, and then separate write
 109  * callbacks for each metadata block and audio frame.
 110  */
 111 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)
 112 {
 113         /* WATCHOUT:
 114          * This depends on the behavior of FLAC__StreamEncoder that 'samples'
 115          * will be 0 for metadata writes.
 116          */
 117         const FLAC__bool is_metadata = (samples == 0);
 118
 119         /*
 120          * Treat fLaC magic packet specially.  We will note when we see it, then
 121          * wait until we get the STREAMINFO and prepend it in that packet
 122          */
 123         if(aspect->seen_magic) {
 124                 ogg_packet packet;
 125                 FLAC__byte synthetic_first_packet_body[
 126                         FLAC__OGG_MAPPING_PACKET_TYPE_LENGTH +
 127                         FLAC__OGG_MAPPING_MAGIC_LENGTH +
 128                         FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH +
 129                         FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH +
 130                         FLAC__OGG_MAPPING_NUM_HEADERS_LENGTH +
 131                         FLAC__STREAM_SYNC_LENGTH +
 132                         FLAC__STREAM_METADATA_HEADER_LENGTH +
 133                         FLAC__STREAM_METADATA_STREAMINFO_LENGTH
 134                 ];
 135
 136                 memset(&packet, 0, sizeof(packet));
 137                 packet.granulepos = aspect->samples_written + samples;
 138
 139                 if(aspect->is_first_packet) {
 140                         FLAC__byte *b = synthetic_first_packet_body;
 141                         if(bytes != FLAC__STREAM_METADATA_HEADER_LENGTH + FLAC__STREAM_METADATA_STREAMINFO_LENGTH) {
 142                                 /*
 143                                  * If we get here, our assumption about the way write callbacks happen
 144                                  * (explained above) is wrong
 145                                  */
 146                                 FLAC__ASSERT(0);
 147                                 return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 148                         }
 149                         /* add first header packet type */
 150                         *b = FLAC__OGG_MAPPING_FIRST_HEADER_PACKET_TYPE;
 151                         b += FLAC__OGG_MAPPING_PACKET_TYPE_LENGTH;
 152                         /* add 'FLAC' mapping magic */
 153                         memcpy(b, FLAC__OGG_MAPPING_MAGIC, FLAC__OGG_MAPPING_MAGIC_LENGTH);
 154                         b += FLAC__OGG_MAPPING_MAGIC_LENGTH;
 155                         /* add Ogg FLAC mapping major version number */
 156                         memcpy(b, &FLAC__OGG_MAPPING_VERSION_MAJOR, FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH);
 157                         b += FLAC__OGG_MAPPING_VERSION_MAJOR_LENGTH;
 158                         /* add Ogg FLAC mapping minor version number */
 159                         memcpy(b, &FLAC__OGG_MAPPING_VERSION_MINOR, FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH);
 160                         b += FLAC__OGG_MAPPING_VERSION_MINOR_LENGTH;
 161                         /* add number of header packets */
 162                         *b = (FLAC__byte)(aspect->num_metadata >> 8);
 163                         b++;
 164                         *b = (FLAC__byte)(aspect->num_metadata);
 165                         b++;
 166                         /* add native FLAC 'fLaC' magic */
 167                         memcpy(b, FLAC__STREAM_SYNC_STRING, FLAC__STREAM_SYNC_LENGTH);
 168                         b += FLAC__STREAM_SYNC_LENGTH;
 169                         /* add STREAMINFO */
 170                         memcpy(b, buffer, bytes);
 171                         FLAC__ASSERT(b + bytes - synthetic_first_packet_body == sizeof(synthetic_first_packet_body));
 172                         packet.packet = (unsigned char *)synthetic_first_packet_body;
 173                         packet.bytes = sizeof(synthetic_first_packet_body);
 174
 175                         packet.b_o_s = 1;
 176                         aspect->is_first_packet = false;
 177                 }
 178                 else {
 179                         packet.packet = (unsigned char *)buffer;
 180                         packet.bytes = bytes;
 181                 }
 182
 183                 if(is_last_block) {
 184                         /* we used to check:
 185                          * FLAC__ASSERT(total_samples_estimate == 0 || total_samples_estimate == aspect->samples_written + samples);
 186                          * but it's really not useful since total_samples_estimate is an estimate and can be inexact
 187                          */
 188                         packet.e_o_s = 1;
 189                 }
 190
 191                 if(ogg_stream_packetin(&aspect->stream_state, &packet) != 0)
 192                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 193
 194                 /*@@@ can't figure out a way to pass a useful number for 'samples' to the write_callback, so we'll just pass 0 */
 195                 if(is_metadata) {
 196                         while(ogg_stream_flush(&aspect->stream_state, &aspect->page) != 0) {
 197                                 if(write_callback(encoder, aspect->page.header, aspect->page.header_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 198                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 199                                 if(write_callback(encoder, aspect->page.body, aspect->page.body_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 200                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 201                         }
 202                 }
 203                 else {
 204                         while(ogg_stream_pageout(&aspect->stream_state, &aspect->page) != 0) {
 205                                 if(write_callback(encoder, aspect->page.header, aspect->page.header_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 206                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 207                                 if(write_callback(encoder, aspect->page.body, aspect->page.body_len, 0, current_frame, client_data) != FLAC__STREAM_ENCODER_WRITE_STATUS_OK)
 208                                         return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 209                         }
 210                 }
 211         }
 212         else if(is_metadata && current_frame == 0 && samples == 0 && bytes == 4 && 0 == memcmp(buffer, FLAC__STREAM_SYNC_STRING, sizeof(FLAC__STREAM_SYNC_STRING))) {
 213                 aspect->seen_magic = true;
 214         }
 215         else {
 216                 /*
 217                  * If we get here, our assumption about the way write callbacks happen
 218                  * explained above is wrong
 219                  */
 220                 FLAC__ASSERT(0);
 221                 return FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
 222         }
 223
 224         aspect->samples_written += samples;
 225
 226         return FLAC__STREAM_ENCODER_WRITE_STATUS_OK;
 227 }