src/flac/utils.c

   1 /* flac - Command-line FLAC encoder/decoder
   2  * Copyright (C) 2002,2003,2004  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 <math.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 static FLAC__bool local__parse_uint64_(const char *s, FLAC__uint64 *value)
  30 {
  31         FLAC__uint64 ret = 0;
  32         char c;
  33
  34         if(*s == '\0')
  35                 return false;
  36
  37         while('\0' != (c = *s++))
  38                 if(c >= '0' && c <= '9')
  39                         ret = ret * 10 + (c - '0');
  40                 else
  41                         return false;
  42
  43         *value = ret;
  44         return true;
  45 }
  46
  47 static FLAC__bool local__parse_timecode_(const char *s, double *value)
  48 {
  49         double ret;
  50         unsigned i;
  51         char c;
  52
  53         /* parse [0-9][0-9]*: */
  54         c = *s++;
  55         if(c >= '0' && c <= '9')
  56                 i = (c - '0');
  57         else
  58                 return false;
  59         while(':' != (c = *s++)) {
  60                 if(c >= '0' && c <= '9')
  61                         i = i * 10 + (c - '0');
  62                 else
  63                         return false;
  64         }
  65         ret = (double)i * 60.;
  66
  67         /* parse [0-9]*[.]?[0-9]* i.e. a sign-less rational number */
  68         if(strspn(s, "1234567890.") != strlen(s))
  69                 return false;
  70         {
  71                 const char *p = strchr(s, '.');
  72                 if(p && 0 != strchr(++p, '.'))
  73                         return false;
  74         }
  75         ret += atof(s);
  76
  77         *value = ret;
  78         return true;
  79 }
  80
  81 static FLAC__bool local__parse_cue_(const char *s, const char *end, unsigned *track, unsigned *index)
  82 {
  83         FLAC__bool got_track = false, got_index = false;
  84         unsigned t = 0, i = 0;
  85         char c;
  86
  87         while(end? s < end : *s != '\0') {
  88                 c = *s++;
  89                 if(c >= '0' && c <= '9') {
  90                         t = t * 10 + (c - '0');
  91                         got_track = true;
  92                 }
  93                 else if(c == '.')
  94                         break;
  95                 else
  96                         return false;
  97         }
  98         while(end? s < end : *s != '\0') {
  99                 c = *s++;
 100                 if(c >= '0' && c <= '9') {
 101                         i = i * 10 + (c - '0');
 102                         got_index = true;
 103                 }
 104                 else
 105                         return false;
 106         }
 107         *track = t;
 108         *index = i;
 109         return got_track && got_index;
 110 }
 111
 112 /*
 113  * @@@ this only works with sorted cuesheets (the spec strongly recommends but
 114  * does not require sorted cuesheets).  but if it's not sorted, picking a
 115  * nearest cue point has no significance.
 116  */
 117 static FLAC__uint64 local__find_closest_cue_(const FLAC__StreamMetadata_CueSheet *cuesheet, unsigned track, unsigned index, FLAC__uint64 total_samples, FLAC__bool look_forward)
 118 {
 119         int t, i;
 120         if(look_forward) {
 121                 for(t = 0; t < (int)cuesheet->num_tracks; t++)
 122                         for(i = 0; i < (int)cuesheet->tracks[t].num_indices; i++)
 123                                 if(cuesheet->tracks[t].number > track || (cuesheet->tracks[t].number == track && cuesheet->tracks[t].indices[i].number >= index))
 124                                         return cuesheet->tracks[t].offset + cuesheet->tracks[t].indices[i].offset;
 125                 return total_samples;
 126         }
 127         else {
 128                 for(t = (int)cuesheet->num_tracks - 1; t >= 0; t--)
 129                         for(i = (int)cuesheet->tracks[t].num_indices - 1; i >= 0; i--)
 130                                 if(cuesheet->tracks[t].number < track || (cuesheet->tracks[t].number == track && cuesheet->tracks[t].indices[i].number <= index))
 131                                         return cuesheet->tracks[t].offset + cuesheet->tracks[t].indices[i].offset;
 132                 return 0;
 133         }
 134 }
 135
 136 #ifdef FLAC__VALGRIND_TESTING
 137 size_t flac__utils_fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream)
 138 {
 139         size_t ret = fwrite(ptr, size, nmemb, stream);
 140         if(!ferror(stream))
 141                 fflush(stream);
 142         return ret;
 143 }
 144 #endif
 145
 146 FLAC__bool flac__utils_parse_skip_until_specification(const char *s, utils__SkipUntilSpecification *spec)
 147 {
 148         FLAC__uint64 val;
 149         FLAC__bool is_negative = false;
 150
 151         FLAC__ASSERT(0 != spec);
 152
 153         spec->is_relative = false;
 154         spec->value_is_samples = true;
 155         spec->value.samples = 0;
 156
 157         if(0 != s) {
 158                 if(s[0] == '-') {
 159                         is_negative = true;
 160                         spec->is_relative = true;
 161                         s++;
 162                 }
 163                 else if(s[0] == '+') {
 164                         spec->is_relative = true;
 165                         s++;
 166                 }
 167
 168                 if(local__parse_uint64_(s, &val)) {
 169                         spec->value_is_samples = true;
 170                         spec->value.samples = (FLAC__int64)val;
 171                         if(is_negative)
 172                                 spec->value.samples = -(spec->value.samples);
 173                 }
 174                 else {
 175                         double d;
 176                         if(!local__parse_timecode_(s, &d))
 177                                 return false;
 178                         spec->value_is_samples = false;
 179                         spec->value.seconds = d;
 180                         if(is_negative)
 181                                 spec->value.seconds = -(spec->value.seconds);
 182                 }
 183         }
 184
 185         return true;
 186 }
 187
 188 void flac__utils_canonicalize_skip_until_specification(utils__SkipUntilSpecification *spec, unsigned sample_rate)
 189 {
 190         FLAC__ASSERT(0 != spec);
 191         if(!spec->value_is_samples) {
 192                 spec->value.samples = (FLAC__int64)(spec->value.seconds * (double)sample_rate);
 193                 spec->value_is_samples = true;
 194         }
 195 }
 196
 197 FLAC__bool flac__utils_parse_cue_specification(const char *s, utils__CueSpecification *spec)
 198 {
 199         const char *start = s, *end = 0;
 200
 201         FLAC__ASSERT(0 != spec);
 202
 203         spec->has_start_point = spec->has_end_point = false;
 204
 205         s = strchr(s, '-');
 206
 207         if(0 != s) {
 208                 if(s == start)
 209                         start = 0;
 210                 end = s+1;
 211                 if(*end == '\0')
 212                         end = 0;
 213         }
 214
 215         if(start) {
 216                 if(!local__parse_cue_(start, s, &spec->start_track, &spec->start_index))
 217                         return false;
 218                 spec->has_start_point = true;
 219         }
 220
 221         if(end) {
 222                 if(!local__parse_cue_(end, 0, &spec->end_track, &spec->end_index))
 223                         return false;
 224                 spec->has_end_point = true;
 225         }
 226
 227         return true;
 228 }
 229
 230 void flac__utils_canonicalize_cue_specification(const utils__CueSpecification *cue_spec, const FLAC__StreamMetadata_CueSheet *cuesheet, FLAC__uint64 total_samples, utils__SkipUntilSpecification *skip_spec, utils__SkipUntilSpecification *until_spec)
 231 {
 232         FLAC__ASSERT(0 != cue_spec);
 233         FLAC__ASSERT(0 != cuesheet);
 234         FLAC__ASSERT(0 != total_samples);
 235         FLAC__ASSERT(0 != skip_spec);
 236         FLAC__ASSERT(0 != until_spec);
 237
 238         skip_spec->is_relative = false;
 239         skip_spec->value_is_samples = true;
 240
 241         until_spec->is_relative = false;
 242         until_spec->value_is_samples = true;
 243
 244         if(cue_spec->has_start_point)
 245                 skip_spec->value.samples = local__find_closest_cue_(cuesheet, cue_spec->start_track, cue_spec->start_index, total_samples, /*look_forward=*/false);
 246         else
 247                 skip_spec->value.samples = 0;
 248
 249         if(cue_spec->has_end_point)
 250                 until_spec->value.samples = local__find_closest_cue_(cuesheet, cue_spec->end_track, cue_spec->end_index, total_samples, /*look_forward=*/true);
 251         else
 252                 until_spec->value.samples = total_samples;
 253 }