src/metaflac/operations_shorthand_seektable.c

   1 /* metaflac - Command-line FLAC metadata editor
   2  * Copyright (C) 2001,2002,2003,2004,2005,2006,2007,2008,2009  Josh Coalson
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #if HAVE_CONFIG_H
  20 #  include <config.h>
  21 #endif
  22
  23 #include "utils.h"
  24 #include "FLAC/assert.h"
  25 #include "FLAC/stream_decoder.h"
  26 #include "FLAC/metadata.h"
  27 #include "share/grabbag.h"
  28 #include "operations_shorthand.h"
  29
  30 static FLAC__bool populate_seekpoint_values(const char *filename, FLAC__StreamMetadata *block, FLAC__bool *needs_write);
  31
  32 FLAC__bool do_shorthand_operation__add_seekpoints(const char *filename, FLAC__Metadata_Chain *chain, const char *specification, FLAC__bool *needs_write)
  33 {
  34         FLAC__bool ok = true, found_seektable_block = false;
  35         FLAC__StreamMetadata *block = 0;
  36         FLAC__Metadata_Iterator *iterator = FLAC__metadata_iterator_new();
  37         FLAC__uint64 total_samples = 0;
  38         unsigned sample_rate = 0;
  39
  40         if(0 == iterator)
  41                 die("out of memory allocating iterator");
  42
  43         FLAC__metadata_iterator_init(iterator, chain);
  44
  45         do {
  46                 block = FLAC__metadata_iterator_get_block(iterator);
  47                 if(block->type == FLAC__METADATA_TYPE_STREAMINFO) {
  48                         sample_rate = block->data.stream_info.sample_rate;
  49                         total_samples = block->data.stream_info.total_samples;
  50                 }
  51                 else if(block->type == FLAC__METADATA_TYPE_SEEKTABLE)
  52                         found_seektable_block = true;
  53         } while(!found_seektable_block && FLAC__metadata_iterator_next(iterator));
  54
  55         if(total_samples == 0) {
  56                 fprintf(stderr, "%s: ERROR: cannot add seekpoints because STREAMINFO block does not specify total_samples\n", filename);
  57                 return false;
  58         }
  59
  60         if(!found_seektable_block) {
  61                 /* create a new block */
  62                 block = FLAC__metadata_object_new(FLAC__METADATA_TYPE_SEEKTABLE);
  63                 if(0 == block)
  64                         die("out of memory allocating SEEKTABLE block");
  65                 while(FLAC__metadata_iterator_prev(iterator))
  66                         ;
  67                 if(!FLAC__metadata_iterator_insert_block_after(iterator, block)) {
  68                         print_error_with_chain_status(chain, "%s: ERROR: adding new SEEKTABLE block to metadata", filename);
  69                         FLAC__metadata_object_delete(block);
  70                         return false;
  71                 }
  72                 /* iterator is left pointing to new block */
  73                 FLAC__ASSERT(FLAC__metadata_iterator_get_block(iterator) == block);
  74         }
  75
  76         FLAC__metadata_iterator_delete(iterator);
  77
  78         FLAC__ASSERT(0 != block);
  79         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_SEEKTABLE);
  80
  81         if(!grabbag__seektable_convert_specification_to_template(specification, /*only_explicit_placeholders=*/false, total_samples, sample_rate, block, /*spec_has_real_points=*/0)) {
  82                 fprintf(stderr, "%s: ERROR (internal) preparing seektable with seekpoints\n", filename);
  83                 return false;
  84         }
  85
  86         ok = populate_seekpoint_values(filename, block, needs_write);
  87
  88         if(ok)
  89                 (void) FLAC__format_seektable_sort(&block->data.seek_table);
  90
  91         return ok;
  92 }
  93
  94 /*
  95  * local routines
  96  */
  97
  98 typedef struct {
  99         FLAC__StreamMetadata_SeekTable *seektable_template;
 100         FLAC__uint64 samples_written;
 101         FLAC__uint64 audio_offset, last_offset;
 102         unsigned first_seekpoint_to_check;
 103         FLAC__bool error_occurred;
 104         FLAC__StreamDecoderErrorStatus error_status;
 105 } ClientData;
 106
 107 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__StreamDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 108 {
 109         ClientData *cd = (ClientData*)client_data;
 110
 111         (void)buffer;
 112         FLAC__ASSERT(0 != cd);
 113
 114         if(!cd->error_occurred) {
 115                 const unsigned blocksize = frame->header.blocksize;
 116                 const FLAC__uint64 frame_first_sample = cd->samples_written;
 117                 const FLAC__uint64 frame_last_sample = frame_first_sample + (FLAC__uint64)blocksize - 1;
 118                 FLAC__uint64 test_sample;
 119                 unsigned i;
 120                 for(i = cd->first_seekpoint_to_check; i < cd->seektable_template->num_points; i++) {
 121                         test_sample = cd->seektable_template->points[i].sample_number;
 122                         if(test_sample > frame_last_sample) {
 123                                 break;
 124                         }
 125                         else if(test_sample >= frame_first_sample) {
 126                                 cd->seektable_template->points[i].sample_number = frame_first_sample;
 127                                 cd->seektable_template->points[i].stream_offset = cd->last_offset - cd->audio_offset;
 128                                 cd->seektable_template->points[i].frame_samples = blocksize;
 129                                 cd->first_seekpoint_to_check++;
 130                                 /* DO NOT: "break;" and here's why:
 131                                  * The seektable template may contain more than one target
 132                                  * sample for any given frame; we will keep looping, generating
 133                                  * duplicate seekpoints for them, and we'll clean it up later,
 134                                  * just before writing the seektable back to the metadata.
 135                                  */
 136                         }
 137                         else {
 138                                 cd->first_seekpoint_to_check++;
 139                         }
 140                 }
 141                 cd->samples_written += blocksize;
 142                 if(!FLAC__stream_decoder_get_decode_position(decoder, &cd->last_offset))
 143                         return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 144                 return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 145         }
 146         else
 147                 return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 148 }
 149
 150 static void error_callback_(const FLAC__StreamDecoder *decoder, FLAC__StreamDecoderErrorStatus status, void *client_data)
 151 {
 152         ClientData *cd = (ClientData*)client_data;
 153
 154         (void)decoder;
 155         FLAC__ASSERT(0 != cd);
 156
 157         if(!cd->error_occurred) { /* don't let multiple errors overwrite the first one */
 158                 cd->error_occurred = true;
 159                 cd->error_status = status;
 160         }
 161 }
 162
 163 FLAC__bool populate_seekpoint_values(const char *filename, FLAC__StreamMetadata *block, FLAC__bool *needs_write)
 164 {
 165         FLAC__StreamDecoder *decoder;
 166         ClientData client_data;
 167         FLAC__bool ok = true;
 168
 169         FLAC__ASSERT(0 != block);
 170         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_SEEKTABLE);
 171
 172         client_data.seektable_template = &block->data.seek_table;
 173         client_data.samples_written = 0;
 174         /* client_data.audio_offset must be determined later */
 175         client_data.first_seekpoint_to_check = 0;
 176         client_data.error_occurred = false;
 177
 178         decoder = FLAC__stream_decoder_new();
 179
 180         if(0 == decoder) {
 181                 fprintf(stderr, "%s: ERROR (--add-seekpoint) creating the decoder instance\n", filename);
 182                 return false;
 183         }
 184
 185         FLAC__stream_decoder_set_md5_checking(decoder, false);
 186         FLAC__stream_decoder_set_metadata_ignore_all(decoder);
 187
 188         if(FLAC__stream_decoder_init_file(decoder, filename, write_callback_, /*metadata_callback=*/0, error_callback_, &client_data) != FLAC__STREAM_DECODER_INIT_STATUS_OK) {
 189                 fprintf(stderr, "%s: ERROR (--add-seekpoint) initializing the decoder instance (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 190                 ok = false;
 191         }
 192
 193         if(ok && !FLAC__stream_decoder_process_until_end_of_metadata(decoder)) {
 194                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 195                 ok = false;
 196         }
 197
 198         if(ok && !FLAC__stream_decoder_get_decode_position(decoder, &client_data.audio_offset)) {
 199                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file\n", filename);
 200                 ok = false;
 201         }
 202         client_data.last_offset = client_data.audio_offset;
 203
 204         if(ok && !FLAC__stream_decoder_process_until_end_of_stream(decoder)) {
 205                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__stream_decoder_get_resolved_state_string(decoder));
 206                 ok = false;
 207         }
 208
 209         if(ok && client_data.error_occurred) {
 210                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%u:%s)\n", filename, (unsigned)client_data.error_status, FLAC__StreamDecoderErrorStatusString[client_data.error_status]);
 211                 ok = false;
 212         }
 213
 214         *needs_write = true;
 215         FLAC__stream_decoder_delete(decoder);
 216         return ok;
 217 }