1 /*! \file exif-content.h 2 * \brief Handling EXIF IFDs 3 */ 4 /* 5 * Copyright (c) 2001 Lutz Mueller <lutz (at) users.sourceforge.net> 6 * 7 * This library is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2 of the License, or (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with this library; if not, write to the 19 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 20 * Boston, MA 02110-1301 USA. 21 */ 22 23 #ifndef __EXIF_CONTENT_H__ 24 #define __EXIF_CONTENT_H__ 25 26 #ifdef __cplusplus 27 extern "C" { 28 #endif /* __cplusplus */ 29 30 /*! Holds all EXIF tags in a single IFD */ 31 typedef struct _ExifContent ExifContent; 32 typedef struct _ExifContentPrivate ExifContentPrivate; 33 34 #include <libexif/exif-tag.h> 35 #include <libexif/exif-entry.h> 36 #include <libexif/exif-data.h> 37 #include <libexif/exif-log.h> 38 #include <libexif/exif-mem.h> 39 40 struct _ExifContent 41 { 42 ExifEntry **entries; 43 unsigned int count; 44 45 /*! Data containing this content */ 46 ExifData *parent; 47 48 ExifContentPrivate *priv; 49 }; 50 51 /* Lifecycle */ 52 ExifContent *exif_content_new (void); 53 ExifContent *exif_content_new_mem (ExifMem *); 54 void exif_content_ref (ExifContent *content); 55 void exif_content_unref (ExifContent *content); 56 void exif_content_free (ExifContent *content); 57 58 /*! Add an EXIF tag to an IFD. 59 * If this tag already exists in the IFD, this function does nothing. 60 * \pre The "tag" member of the entry must be set on entry. 61 * 62 * \param[out] c IFD 63 * \param[in] entry EXIF entry to add 64 */ 65 void exif_content_add_entry (ExifContent *c, ExifEntry *entry); 66 67 /*! Remove an EXIF tag from an IFD. 68 * If this tag does not exist in the IFD, this function does nothing. 69 * 70 * \param[out] c IFD 71 * \param[in] e EXIF entry to remove 72 */ 73 void exif_content_remove_entry (ExifContent *c, ExifEntry *e); 74 75 /*! Return the #ExifEntry in this IFD corresponding to the given tag. 76 * This is a pointer into a member of the #ExifContent array and must NOT be 77 * freed or unrefed by the caller. 78 * 79 * \param[in] content EXIF content for an IFD 80 * \param[in] tag EXIF tag to return 81 * \return #ExifEntry of the tag, or NULL on error 82 */ 83 ExifEntry *exif_content_get_entry (ExifContent *content, ExifTag tag); 84 85 /*! Fix the IFD to bring it into specification. Call #exif_entry_fix on 86 * each entry in this IFD to fix existing entries, create any new entries 87 * that are mandatory in this IFD but do not yet exist, and remove any 88 * entries that are not allowed in this IFD. 89 * 90 * \param[in,out] c EXIF content for an IFD 91 */ 92 void exif_content_fix (ExifContent *c); 93 94 typedef void (* ExifContentForeachEntryFunc) (ExifEntry *, void *user_data); 95 96 /*! Executes function on each EXIF tag in this IFD in turn. 97 * The tags will not necessarily be visited in numerical order. 98 * 99 * \param[in,out] content IFD over which to iterate 100 * \param[in] func function to call for each entry 101 * \param[in] user_data data to pass into func on each call 102 */ 103 void exif_content_foreach_entry (ExifContent *content, 104 ExifContentForeachEntryFunc func, 105 void *user_data); 106 107 /*! Return the IFD number in which the given #ExifContent is found. 108 * 109 * \param[in] c an #ExifContent* 110 * \return IFD number, or #EXIF_IFD_COUNT on error 111 */ 112 ExifIfd exif_content_get_ifd (ExifContent *c); 113 114 /*! Return a textual representation of the EXIF data for a tag. 115 * 116 * \param[in] c #ExifContent* for an IFD 117 * \param[in] t #ExifTag to return 118 * \param[out] v char* buffer in which to store value 119 * \param[in] m unsigned int length of the buffer v 120 * \return the v pointer, or NULL on error 121 */ 122 #define exif_content_get_value(c,t,v,m) \ 123 (exif_content_get_entry (c,t) ? \ 124 exif_entry_get_value (exif_content_get_entry (c,t),v,m) : NULL) 125 126 /*! Dump contents of the IFD to stdout. 127 * This is intended for diagnostic purposes only. 128 * 129 * \param[in] content IFD data 130 * \param[in] indent how many levels deep to indent the data 131 */ 132 void exif_content_dump (ExifContent *content, unsigned int indent); 133 134 /*! Set the log message object for this IFD. 135 * 136 * \param[in] content IFD 137 * \param[in] log #ExifLog* 138 */ 139 void exif_content_log (ExifContent *content, ExifLog *log); 140 141 #ifdef __cplusplus 142 } 143 #endif /* __cplusplus */ 144 145 #endif /* __EXIF_CONTENT_H__ */ 146
