src/metaflac/operations_shorthand_seektable.c

   1 /* metaflac - Command-line FLAC metadata editor
   2  * Copyright (C) 2001-2009  Josh Coalson
   3  * Copyright (C) 2011-2013  Xiph.Org Foundation
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License
   7  * as published by the Free Software Foundation; either version 2
   8  * of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #if HAVE_CONFIG_H
  21 #  include <config.h>
  22 #endif
  23
  24 #include "utils.h"
  25 #include "FLAC/assert.h"
  26 #include "FLAC/stream_decoder.h"
  27 #include "FLAC/metadata.h"
  28 #include "share/grabbag.h"
  29 #include "operations_shorthand.h"
  30
  31 static FLAC__bool populate_seekpoint_values(const char *filename, FLAC__StreamMetadata *block, FLAC__bool *needs_write);
  32
  33 FLAC__bool do_shorthand_operation__add_seekpoints(const char *filename, FLAC__Metadata_Chain *chain, const char *specification, FLAC__bool *needs_write)
  34 {
  35         FLAC__bool ok = true, found_seektable_block = false;
  36         FLAC__StreamMetadata *block = 0;
  37         FLAC__Metadata_Iterator *iterator = FLAC__metadata_iterator_new();
  38         FLAC__uint64 total_samples = 0;
  39         unsigned sample_rate = 0;
  40
  41         if(0 == iterator)
  42                 die("out of memory allocating iterator");
  43
  44         FLAC__metadata_iterator_init(iterator, chain);
  45
  46         do {
  47                 block = FLAC__metadata_iterator_get_block(iterator);
  48                 if(block->type == FLAC__METADATA_TYPE_STREAMINFO) {
  49                         sample_rate = block->data.stream_info.sample_rate;
  50                         total_samples = block->data.stream_info.total_samples;
  51                 }
  52                 else if(block->type == FLAC__METADATA_TYPE_SEEKTABLE)
  53                         found_seektable_block = true;
  54         } while(!found_seektable_block && FLAC__metadata_iterator_next(iterator));
  55
  56         if(total_samples == 0) {
  57                 flac_fprintf(stderr, "%s: ERROR: cannot add seekpoints because STREAMINFO block does not specify total_samples\n", filename);
  58                 return false;
  59         }
  60
  61         if(!found_seektable_block) {
  62                 /* create a new block */
  63                 block = FLAC__metadata_object_new(FLAC__METADATA_TYPE_SEEKTABLE);
  64                 if(0 == block)
  65                         die("out of memory allocating SEEKTABLE block");
  66                 while(FLAC__metadata_iterator_prev(iterator))
  67                         ;
  68                 if(!FLAC__metadata_iterator_insert_block_after(iterator, block)) {
  69                         print_error_with_chain_status(chain, "%s: ERROR: adding new SEEKTABLE block to metadata", filename);
  70                         FLAC__metadata_object_delete(block);
  71                         return false;
  72                 }
  73                 /* iterator is left pointing to new block */
  74                 FLAC__ASSERT(FLAC__metadata_iterator_get_block(iterator) == block);
  75         }
  76
  77         FLAC__metadata_iterator_delete(iterator);
  78
  79         FLAC__ASSERT(0 != block);
  80         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_SEEKTABLE);
  81
  82         if(!grabbag__seektable_convert_specification_to_template(specification, /*only_explicit_placeholders=*/false, total_samples, sample_rate, block, /*spec_has_real_points=*/0)) {
  83                 flac_fprintf(stderr, "%s: ERROR (internal) preparing seektable with seekpoints\n", filename);
  84                 return false;
  85         }
  86
  87         ok = populate_seekpoint_values(filename, block, needs_write);
  88
  89         if(ok)
  90                 (void) FLAC__format_seektable_sort(&block->data.seek_table);
  91
  92         return ok;
  93 }
  94
  95 /*
  96  * local routines
  97  */
  98
  99 typedef struct {
 100         FLAC__StreamMetadata_SeekTable *seektable_template;
 101         FLAC__uint64 samples_written;
 102         FLAC__uint64 audio_offset, last_offset;
 103         unsigned first_seekpoint_to_check;
 104         FLAC__bool error_occurred;
 105         FLAC__StreamDecoderErrorStatus error_status;
 106 } ClientData;
 107
 108 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 109 {
 110         ClientData *cd = (ClientData*)client_data;
 111
 112         (void)buffer;
 113         FLAC__ASSERT(0 != cd);
 114
 115         if(!cd->error_occurred) {
 116                 const unsigned blocksize = frame->header.blocksize;
 117                 const FLAC__uint64 frame_first_sample = cd->samples_written;
 118                 const FLAC__uint64 frame_last_sample = frame_first_sample + (FLAC__uint64)blocksize - 1;
 119                 FLAC__uint64 test_sample;
 120                 unsigned i;
 121                 for(i = cd->first_seekpoint_to_check; i < cd->seektable_template->num_points; i++) {
 122                         test_sample = cd->seektable_template->points[i].sample_number;
 123                         if(test_sample > frame_last_sample) {
 124                                 break;
 125                         }
 126                         else if(test_sample >= frame_first_sample) {
 127                                 cd->seektable_template->points[i].sample_number = frame_first_sample;
 128                                 cd->seektable_template->points[i].stream_offset = cd->last_offset - cd->audio_offset;
 129                                 cd->seektable_template->points[i].frame_samples = blocksize;
 130                                 cd->first_seekpoint_to_check++;
 131                                 /* DO NOT: "break;" and here's why:
 132                                  * The seektable template may contain more than one target
 133                                  * sample for any given frame; we will keep looping, generating
 134                                  * duplicate seekpoints for them, and we'll clean it up later,
 135                                  * just before writing the seektable back to the metadata.
 136                                  */
 137                         }
 138                         else {
 139                                 cd->first_seekpoint_to_check++;
 140                         }
 141                 }
 142                 cd->samples_written += blocksize;
 143                 if(!FLAC__stream_decoder_get_decode_position(decoder, &cd->last_offset))
 144                         return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 145                 return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 146         }
 147         else
 148                 return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 149 }
 150
 151 static void error_callback_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
 152 {
 153         ClientData *cd = (ClientData*)client_data;
 154
 155         (void)decoder;
 156         FLAC__ASSERT(0 != cd);
 157
 158         if(!cd->error_occurred) { /* don't let multiple errors overwrite the first one */
 159                 cd->error_occurred = true;
 160                 cd->error_status = status;
 161         }
 162 }
 163
 164 FLAC__bool populate_seekpoint_values(const char *filename, FLAC__StreamMetadata *block, FLAC__bool *needs_write)
 165 {
 166         FLAC__StreamDecoder *decoder;
 167         ClientData client_data;
 168         FLAC__bool ok = true;
 169
 170         FLAC__ASSERT(0 != block);
 171         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_SEEKTABLE);
 172
 173         client_data.seektable_template = &block->data.seek_table;
 174         client_data.samples_written = 0;
 175         /* client_data.audio_offset must be determined later */
 176         client_data.first_seekpoint_to_check = 0;
 177         client_data.error_occurred = false;
 178
 179         decoder = FLAC__stream_decoder_new();
 180
 181         if(0 == decoder) {
 182                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) creating the decoder instance\n", filename);
 183                 return false;
 184         }
 185
 186         FLAC__stream_decoder_set_md5_checking(decoder, false);
 187         FLAC__stream_decoder_set_metadata_ignore_all(decoder);
 188
 189         if(FLAC__stream_decoder_init_file(decoder, filename, write_callback_, /*metadata_callback=*/0, error_callback_, &client_data) != FLAC__STREAM_DECODER_INIT_STATUS_OK) {
 190                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) initializing the decoder instance (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 191                 ok = false;
 192         }
 193
 194         if(ok && !FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
 195                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 196                 ok = false;
 197         }
 198
 199         if(ok && !FLAC__stream_decoder_get_decode_position(decoder, &client_data.audio_offset)) {
 200                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file\n", filename);
 201                 ok = false;
 202         }
 203         client_data.last_offset = client_data.audio_offset;
 204
 205         if(ok && !FLAC__stream_decoder_process_until_end_of_stream(decoder)) {
 206                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 207                 ok = false;
 208         }
 209
 210         if(ok && client_data.error_occurred) {
 211                 flac_fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%u:%s)\n", filename, (unsigned)client_data.error_status, FLAC__StreamDecoderErrorStatusString[client_data.error_status]);
 212                 ok = false;
 213         }
 214
 215         *needs_write = true;
 216         FLAC__stream_decoder_delete(decoder);
 217         return ok;
 218 }