1 /* exif-content.c 2 * 3 * Copyright (c) 2001 Lutz Mueller <lutz (at) users.sourceforge.net> 4 * 5 * This library is free software; you can redistribute it and/or 6 * modify it under the terms of the GNU Lesser General Public 7 * License as published by the Free Software Foundation; either 8 * version 2 of the License, or (at your option) any later version. 9 * 10 * This library 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 GNU 13 * Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public 16 * License along with this library; if not, write to the 17 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 18 * Boston, MA 02110-1301 USA. 19 */ 20 21 #include <config.h> 22 23 #include <libexif/exif-content.h> 24 #include <libexif/exif-system.h> 25 26 #include <stdlib.h> 27 #include <stdio.h> 28 #include <string.h> 29 30 /* unused constant 31 * static const unsigned char ExifHeader[] = {0x45, 0x78, 0x69, 0x66, 0x00, 0x00}; 32 */ 33 34 struct _ExifContentPrivate 35 { 36 unsigned int ref_count; 37 38 ExifMem *mem; 39 ExifLog *log; 40 }; 41 42 ExifContent * 43 exif_content_new (void) 44 { 45 ExifMem *mem = exif_mem_new_default (); 46 ExifContent *content = exif_content_new_mem (mem); 47 48 exif_mem_unref (mem); 49 50 return content; 51 } 52 53 ExifContent * 54 exif_content_new_mem (ExifMem *mem) 55 { 56 ExifContent *content; 57 58 if (!mem) return NULL; 59 60 content = exif_mem_alloc (mem, (ExifLong) sizeof (ExifContent)); 61 if (!content) 62 return NULL; 63 content->priv = exif_mem_alloc (mem, 64 (ExifLong) sizeof (ExifContentPrivate)); 65 if (!content->priv) { 66 exif_mem_free (mem, content); 67 return NULL; 68 } 69 70 content->priv->ref_count = 1; 71 72 content->priv->mem = mem; 73 exif_mem_ref (mem); 74 75 return content; 76 } 77 78 void 79 exif_content_ref (ExifContent *content) 80 { 81 content->priv->ref_count++; 82 } 83 84 void 85 exif_content_unref (ExifContent *content) 86 { 87 content->priv->ref_count--; 88 if (!content->priv->ref_count) 89 exif_content_free (content); 90 } 91 92 void 93 exif_content_free (ExifContent *content) 94 { 95 ExifMem *mem = (content && content->priv) ? content->priv->mem : NULL; 96 unsigned int i; 97 98 if (!content) return; 99 100 for (i = 0; i < content->count; i++) 101 exif_entry_unref (content->entries[i]); 102 exif_mem_free (mem, content->entries); 103 104 if (content->priv) { 105 exif_log_unref (content->priv->log); 106 } 107 108 exif_mem_free (mem, content->priv); 109 exif_mem_free (mem, content); 110 exif_mem_unref (mem); 111 } 112 113 void 114 exif_content_dump (ExifContent *content, unsigned int indent) 115 { 116 char buf[1024]; 117 unsigned int i; 118 119 for (i = 0; i < 2 * indent; i++) 120 buf[i] = ' '; 121 buf[i] = '\0'; 122 123 if (!content) 124 return; 125 126 printf ("%sDumping exif content (%u entries)...\n", buf, 127 content->count); 128 for (i = 0; i < content->count; i++) 129 exif_entry_dump (content->entries[i], indent + 1); 130 } 131 132 void 133 exif_content_add_entry (ExifContent *c, ExifEntry *entry) 134 { 135 ExifEntry **entries; 136 if (!c || !c->priv || !entry || entry->parent) return; 137 138 /* One tag can only be added once to an IFD. */ 139 if (exif_content_get_entry (c, entry->tag)) { 140 exif_log (c->priv->log, EXIF_LOG_CODE_DEBUG, "ExifContent", 141 "An attempt has been made to add " 142 "the tag '%s' twice to an IFD. This is against " 143 "specification.", exif_tag_get_name (entry->tag)); 144 return; 145 } 146 147 entries = exif_mem_realloc (c->priv->mem, 148 c->entries, sizeof (ExifEntry*) * (c->count + 1)); 149 if (!entries) return; 150 entry->parent = c; 151 entries[c->count++] = entry; 152 c->entries = entries; 153 exif_entry_ref (entry); 154 } 155 156 void 157 exif_content_remove_entry (ExifContent *c, ExifEntry *e) 158 { 159 unsigned int i; 160 ExifEntry **t, *temp; 161 162 if (!c || !c->priv || !e || (e->parent != c)) return; 163 164 /* Search the entry */ 165 for (i = 0; i < c->count; i++) 166 if (c->entries[i] == e) 167 break; 168 169 if (i == c->count) 170 return; 171 172 /* Remove the entry */ 173 temp = c->entries[c->count-1]; 174 if (c->count > 1) { 175 t = exif_mem_realloc (c->priv->mem, c->entries, 176 sizeof(ExifEntry*) * (c->count - 1)); 177 if (!t) { 178 return; 179 } 180 c->entries = t; 181 c->count--; 182 if (i != c->count) { /* we deallocated the last slot already */ 183 memmove (&t[i], &t[i + 1], sizeof (ExifEntry*) * (c->count - i - 1)); 184 t[c->count-1] = temp; 185 } 186 } else { 187 exif_mem_free (c->priv->mem, c->entries); 188 c->entries = NULL; 189 c->count = 0; 190 } 191 e->parent = NULL; 192 exif_entry_unref (e); 193 } 194 195 ExifEntry * 196 exif_content_get_entry (ExifContent *content, ExifTag tag) 197 { 198 unsigned int i; 199 200 if (!content) 201 return (NULL); 202 203 for (i = 0; i < content->count; i++) 204 if (content->entries[i]->tag == tag) 205 return (content->entries[i]); 206 return (NULL); 207 } 208 209 void 210 exif_content_foreach_entry (ExifContent *content, 211 ExifContentForeachEntryFunc func, void *data) 212 { 213 unsigned int i; 214 215 if (!content || !func) 216 return; 217 218 for (i = 0; i < content->count; i++) 219 func (content->entries[i], data); 220 } 221 222 void 223 exif_content_log (ExifContent *content, ExifLog *log) 224 { 225 if (!content || !content->priv || !log || content->priv->log == log) 226 return; 227 228 if (content->priv->log) exif_log_unref (content->priv->log); 229 content->priv->log = log; 230 exif_log_ref (log); 231 } 232 233 ExifIfd 234 exif_content_get_ifd (ExifContent *c) 235 { 236 if (!c || !c->parent) return EXIF_IFD_COUNT; 237 238 return 239 ((c)->parent->ifd[EXIF_IFD_EXIF] == (c)) ? EXIF_IFD_EXIF : 240 ((c)->parent->ifd[EXIF_IFD_0] == (c)) ? EXIF_IFD_0 : 241 ((c)->parent->ifd[EXIF_IFD_1] == (c)) ? EXIF_IFD_1 : 242 ((c)->parent->ifd[EXIF_IFD_GPS] == (c)) ? EXIF_IFD_GPS : 243 ((c)->parent->ifd[EXIF_IFD_INTEROPERABILITY] == (c)) ? EXIF_IFD_INTEROPERABILITY : 244 EXIF_IFD_COUNT; 245 } 246 247 static void 248 fix_func (ExifEntry *e, void *UNUSED(data)) 249 { 250 exif_entry_fix (e); 251 } 252 253 /*! 254 * Check if this entry is unknown and if so, delete it. 255 * \note Be careful calling this function in a loop. Deleting an entry from 256 * an ExifContent changes the index of subsequent entries, as well as the 257 * total size of the entries array. 258 */ 259 static void 260 remove_not_recorded (ExifEntry *e, void *UNUSED(data)) 261 { 262 ExifIfd ifd = exif_entry_get_ifd(e) ; 263 ExifContent *c = e->parent; 264 ExifDataType dt = exif_data_get_data_type (c->parent); 265 ExifTag t = e->tag; 266 267 if (exif_tag_get_support_level_in_ifd (t, ifd, dt) == 268 EXIF_SUPPORT_LEVEL_NOT_RECORDED) { 269 exif_log (c->priv->log, EXIF_LOG_CODE_DEBUG, "exif-content", 270 "Tag 0x%04x is not recorded in IFD '%s' and has therefore been " 271 "removed.", t, exif_ifd_get_name (ifd)); 272 exif_content_remove_entry (c, e); 273 } 274 275 } 276 277 void 278 exif_content_fix (ExifContent *c) 279 { 280 ExifIfd ifd = exif_content_get_ifd (c); 281 ExifDataType dt; 282 ExifEntry *e; 283 unsigned int i, num; 284 285 if (!c) 286 return; 287 288 dt = exif_data_get_data_type (c->parent); 289 290 /* 291 * First of all, fix all existing entries. 292 */ 293 exif_content_foreach_entry (c, fix_func, NULL); 294 295 /* 296 * Go through each tag and if it's not recorded, remove it. If one 297 * is removed, exif_content_foreach_entry() will skip the next entry, 298 * so if this happens do the loop again from the beginning to ensure 299 * they're all checked. This could be avoided if we stop relying on 300 * exif_content_foreach_entry but loop intelligently here. 301 */ 302 do { 303 num = c->count; 304 exif_content_foreach_entry (c, remove_not_recorded, NULL); 305 } while (num != c->count); 306 307 /* 308 * Then check for non-existing mandatory tags and create them if needed 309 */ 310 num = exif_tag_table_count(); 311 for (i = 0; i < num; ++i) { 312 const ExifTag t = exif_tag_table_get_tag (i); 313 if (exif_tag_get_support_level_in_ifd (t, ifd, dt) == 314 EXIF_SUPPORT_LEVEL_MANDATORY) { 315 if (exif_content_get_entry (c, t)) 316 /* This tag already exists */ 317 continue; 318 exif_log (c->priv->log, EXIF_LOG_CODE_DEBUG, "exif-content", 319 "Tag '%s' is mandatory in IFD '%s' and has therefore been added.", 320 exif_tag_get_name_in_ifd (t, ifd), exif_ifd_get_name (ifd)); 321 e = exif_entry_new (); 322 exif_content_add_entry (c, e); 323 exif_entry_initialize (e, t); 324 exif_entry_unref (e); 325 } 326 } 327 } 328
