src/metaflac/operations_shorthand_seektable.c

   1 /* metaflac - Command-line FLAC metadata editor
   2  * Copyright (C) 2001,2002,2003,2004,2005  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
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  17  */
  18
  19 #include "utils.h"
  20 #include "FLAC/assert.h"
  21 #include "FLAC/file_decoder.h"
  22 #include "FLAC/metadata.h"
  23 #include "share/grabbag.h"
  24
  25 static FLAC__bool populate_seekpoint_values(const char *filename, FLAC__StreamMetadata *block, FLAC__bool *needs_write);
  26
  27 FLAC__bool do_shorthand_operation__add_seekpoints(const char *filename, FLAC__Metadata_Chain *chain, const char *specification, FLAC__bool *needs_write)
  28 {
  29         FLAC__bool ok = true, found_seektable_block = false;
  30         FLAC__StreamMetadata *block = 0;
  31         FLAC__Metadata_Iterator *iterator = FLAC__metadata_iterator_new();
  32         FLAC__uint64 total_samples = 0;
  33         unsigned sample_rate = 0;
  34
  35         if(0 == iterator)
  36                 die("out of memory allocating iterator");
  37
  38         FLAC__metadata_iterator_init(iterator, chain);
  39
  40         do {
  41                 block = FLAC__metadata_iterator_get_block(iterator);
  42                 if(block->type == FLAC__METADATA_TYPE_STREAMINFO) {
  43                         sample_rate = block->data.stream_info.sample_rate;
  44                         total_samples = block->data.stream_info.total_samples;
  45                 }
  46                 else if(block->type == FLAC__METADATA_TYPE_SEEKTABLE)
  47                         found_seektable_block = true;
  48         } while(!found_seektable_block && FLAC__metadata_iterator_next(iterator));
  49
  50         if(total_samples == 0) {
  51                 fprintf(stderr, "%s: ERROR: cannot add seekpoints because STREAMINFO block does not specify total_samples\n", filename);
  52                 return false;
  53         }
  54
  55         if(!found_seektable_block) {
  56                 /* create a new block */
  57                 block = FLAC__metadata_object_new(FLAC__METADATA_TYPE_SEEKTABLE);
  58                 if(0 == block)
  59                         die("out of memory allocating SEEKTABLE block");
  60                 while(FLAC__metadata_iterator_prev(iterator))
  61                         ;
  62                 if(!FLAC__metadata_iterator_insert_block_after(iterator, block)) {
  63                         print_error_with_chain_status(chain, "%s: ERROR: adding new SEEKTABLE block to metadata", filename);
  64                         FLAC__metadata_object_delete(block);
  65                         return false;
  66                 }
  67                 /* iterator is left pointing to new block */
  68                 FLAC__ASSERT(FLAC__metadata_iterator_get_block(iterator) == block);
  69         }
  70
  71         FLAC__metadata_iterator_delete(iterator);
  72
  73         FLAC__ASSERT(0 != block);
  74         FLAC__ASSERT(block->type == FLAC__METADATA_TYPE_SEEKTABLE);
  75
  76         if(!grabbag__seektable_convert_specification_to_template(specification, /*only_explicit_placeholders=*/false, total_samples, sample_rate, block, /*spec_has_real_points=*/0)) {
  77                 fprintf(stderr, "%s: ERROR (internal) preparing seektable with seekpoints\n", filename);
  78                 return false;
  79         }
  80
  81         ok = populate_seekpoint_values(filename, block, needs_write);
  82
  83         if(ok)
  84                 (void) FLAC__format_seektable_sort(&block->data.seek_table);
  85
  86         return ok;
  87 }
  88
  89 /*
  90  * local routines
  91  */
  92
  93 typedef struct {
  94         FLAC__StreamMetadata_SeekTable *seektable_template;
  95         FLAC__uint64 samples_written;
  96         FLAC__uint64 audio_offset, last_offset;
  97         unsigned first_seekpoint_to_check;
  98         FLAC__bool error_occurred;
  99         FLAC__StreamDecoderErrorStatus error_status;
 100 } ClientData;
 101
 102 static FLAC__StreamDecoderWriteStatus write_callback_(const FLAC__FileDecoder *decoder, const FLAC__Frame *frame, const FLAC__int32 * const buffer[], void *client_data)
 103 {
 104         ClientData *cd = (ClientData*)client_data;
 105
 106         (void)buffer;
 107         FLAC__ASSERT(0 != cd);
 108
 109         if(!cd->error_occurred && cd->seektable_template->num_points > 0) {
 110                 const unsigned blocksize = frame->header.blocksize;
 111                 const FLAC__uint64 frame_first_sample = cd->samples_written;
 112                 const FLAC__uint64 frame_last_sample = frame_first_sample + (FLAC__uint64)blocksize - 1;
 113                 FLAC__uint64 test_sample;
 114                 unsigned i;
 115                 for(i = cd->first_seekpoint_to_check; i < cd->seektable_template->num_points; i++) {
 116                         test_sample = cd->seektable_template->points[i].sample_number;
 117                         if(test_sample > frame_last_sample) {
 118                                 break;
 119                         }
 120                         else if(test_sample >= frame_first_sample) {
 121                                 cd->seektable_template->points[i].sample_number = frame_first_sample;
 122                                 cd->seektable_template->points[i].stream_offset = cd->last_offset - cd->audio_offset;
 123                                 cd->seektable_template->points[i].frame_samples = blocksize;
 124                                 cd->first_seekpoint_to_check++;
 125                                 /* DO NOT: "break;" and here's why:
 126                                  * The seektable template may contain more than one target
 127                                  * sample for any given frame; we will keep looping, generating
 128                                  * duplicate seekpoints for them, and we'll clean it up later,
 129                                  * just before writing the seektable back to the metadata.
 130                                  */
 131                         }
 132                         else {
 133                                 cd->first_seekpoint_to_check++;
 134                         }
 135                 }
 136                 cd->samples_written += blocksize;
 137                 if(!FLAC__file_decoder_get_decode_position(decoder, &cd->last_offset))
 138                         return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 139                 return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
 140         }
 141         else
 142                 return FLAC__STREAM_DECODER_WRITE_STATUS_ABORT;
 143 }
 144
 145 static void metadata_callback_(const FLAC__FileDecoder *decoder, const FLAC__StreamMetadata *metadata, void *client_data)
 146 {
 147         (void)decoder, (void)metadata, (void)client_data;
 148         FLAC__ASSERT(0); /* we asked to skip all metadata */
 149 }
 150
 151 static void error_callback_(const FLAC__FileDecoder *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__FileDecoder *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__file_decoder_new();
 180
 181         if(0 == decoder) {
 182                 fprintf(stderr, "%s: ERROR (--add-seekpoint) creating the decoder instance\n", filename);
 183                 return false;
 184         }
 185
 186         FLAC__file_decoder_set_md5_checking(decoder, false);
 187         FLAC__file_decoder_set_filename(decoder, filename);
 188         FLAC__file_decoder_set_metadata_ignore_all(decoder);
 189         FLAC__file_decoder_set_write_callback(decoder, write_callback_);
 190         FLAC__file_decoder_set_metadata_callback(decoder, metadata_callback_);
 191         FLAC__file_decoder_set_error_callback(decoder, error_callback_);
 192         FLAC__file_decoder_set_client_data(decoder, &client_data);
 193
 194         if(FLAC__file_decoder_init(decoder) != FLAC__FILE_DECODER_OK) {
 195                 fprintf(stderr, "%s: ERROR (--add-seekpoint) initializing the decoder instance (%s)\n", filename, FLAC__file_decoder_get_resolved_state_string(decoder));
 196                 ok = false;
 197         }
 198
 199         if(ok && !FLAC__file_decoder_process_until_end_of_metadata(decoder)) {
 200                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__file_decoder_get_resolved_state_string(decoder));
 201                 ok = false;
 202         }
 203
 204         if(ok && !FLAC__file_decoder_get_decode_position(decoder, &client_data.audio_offset)) {
 205                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file\n", filename);
 206                 ok = false;
 207         }
 208         client_data.last_offset = client_data.audio_offset;
 209
 210         if(ok && !FLAC__file_decoder_process_until_end_of_file(decoder)) {
 211                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%s)\n", filename, FLAC__file_decoder_get_resolved_state_string(decoder));
 212                 ok = false;
 213         }
 214
 215         if(ok && client_data.error_occurred) {
 216                 fprintf(stderr, "%s: ERROR (--add-seekpoint) decoding file (%u:%s)\n", filename, (unsigned)client_data.error_status, FLAC__StreamDecoderErrorStatusString[client_data.error_status]);
 217                 ok = false;
 218         }
 219
 220         *needs_write = true;
 221         FLAC__file_decoder_delete(decoder);
 222         return ok;
 223 }