Fix buffer overflow by replacing strcpy with memcpy.
[flac.git] / 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
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 #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 }