1 /*! \file exif-loader.h 2 * \brief Defines the ExifLoader type 3 */ 4 /* 5 * Copyright (c) 2003 Lutz Mueller <lutz@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_LOADER_H__ 24 #define __EXIF_LOADER_H__ 25 26 #include <libexif/exif-data.h> 27 #include <libexif/exif-log.h> 28 #include <libexif/exif-mem.h> 29 30 #ifdef __cplusplus 31 extern "C" { 32 #endif /* __cplusplus */ 33 34 /*! Data used by the loader interface */ 35 typedef struct _ExifLoader ExifLoader; 36 37 /*! Allocate a new #ExifLoader. 38 * 39 * \return allocated ExifLoader 40 */ 41 ExifLoader *exif_loader_new (void); 42 43 /*! Allocate a new #ExifLoader using the specified memory allocator. 44 * 45 * \param[in] mem the ExifMem 46 * \return allocated ExifLoader 47 */ 48 ExifLoader *exif_loader_new_mem (ExifMem *mem); 49 50 /*! Increase the refcount of the #ExifLoader. 51 * 52 * \param[in] loader the ExifLoader to increase the refcount of. 53 */ 54 void exif_loader_ref (ExifLoader *loader); 55 56 /*! Decrease the refcount of the #ExifLoader. 57 * If the refcount reaches 0, the loader is freed. 58 * 59 * \param[in] loader ExifLoader for which to decrease the refcount 60 */ 61 void exif_loader_unref (ExifLoader *loader); 62 63 /*! Load a file into the given #ExifLoader from the filesystem. 64 * The relevant data is copied in raw form into the #ExifLoader. 65 * 66 * \param[in] loader loader to write to 67 * \param[in] fname path to the file to read 68 */ 69 void exif_loader_write_file (ExifLoader *loader, const char *fname); 70 71 /*! Load a buffer into the #ExifLoader from a memory buffer. 72 * The relevant data is copied in raw form into the #ExifLoader. 73 * 74 * \param[in] loader loader to write to 75 * \param[in] buf buffer to read from 76 * \param[in] sz size of the buffer 77 * \return 1 while EXIF data is read (or while there is still hope that 78 * there will be EXIF data later on), 0 otherwise. 79 */ 80 unsigned char exif_loader_write (ExifLoader *loader, unsigned char *buf, unsigned int sz); 81 82 /*! Free any data previously loaded and reset the #ExifLoader to its 83 * newly-initialized state. 84 * 85 * \param[in] loader the loader 86 */ 87 void exif_loader_reset (ExifLoader *loader); 88 89 /*! Create an #ExifData from the data in the loader. The loader must 90 * already contain data from a previous call to #exif_loader_write_file 91 * or #exif_loader_write. 92 * 93 * \note The #ExifData returned is created using its default options, which 94 * may take effect before the data is returned. If other options are desired, 95 * an #ExifData must be created explicitly and data extracted from the loader 96 * using #exif_loader_get_buf instead. 97 * 98 * \param[in] loader the loader 99 * \return allocated ExifData 100 * 101 * \see exif_loader_get_buf 102 */ 103 ExifData *exif_loader_get_data (ExifLoader *loader); 104 105 /*! Return the raw data read by the loader. The returned pointer is only 106 * guaranteed to be valid until the next call to a function modifying 107 * this #ExifLoader. Either or both of buf and buf_size may be NULL on 108 * entry, in which case that value is not returned. 109 * 110 * \param[in] loader the loader 111 * \param[out] buf read-only pointer to the data read by the loader, or NULL 112 * in case of error 113 * \param[out] buf_size size of the data at buf, or 0 in case of error 114 */ 115 void exif_loader_get_buf (ExifLoader *loader, const unsigned char **buf, 116 unsigned int *buf_size); 117 118 /*! Set the log message object used by this #ExifLoader. 119 * \param[in] loader the loader 120 * \param[in] log #ExifLog 121 */ 122 void exif_loader_log (ExifLoader *loader, ExifLog *log); 123 124 #ifdef __cplusplus 125 } 126 #endif /* __cplusplus */ 127 128 #endif /* __EXIF_LOADER_H__ */ 129