1 /*! \file exif-log.h 2 * \brief Log message infrastructure 3 */ 4 /* 5 * Copyright (c) 2004 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 * SPDX-License-Identifier: LGPL-2.0-or-later 23 */ 24 25 #ifndef LIBEXIF_EXIF_LOG_H 26 #define LIBEXIF_EXIF_LOG_H 27 28 #ifdef __cplusplus 29 extern "C" { 30 #endif /* __cplusplus */ 31 32 #include <libexif/exif-mem.h> 33 #include <stdarg.h> 34 35 /*! State maintained by the logging interface */ 36 typedef struct _ExifLog ExifLog; 37 38 /*! Create a new logging instance. 39 * \see exif_log_free 40 * 41 * \return new instance of #ExifLog 42 */ 43 ExifLog *exif_log_new (void); 44 ExifLog *exif_log_new_mem (ExifMem *); 45 void exif_log_ref (ExifLog *log); 46 void exif_log_unref (ExifLog *log); 47 48 /*! Delete instance of #ExifLog. 49 * \see exif_log_new 50 * 51 * \param[in] log #ExifLog 52 * \return new instance of #ExifLog 53 */ 54 void exif_log_free (ExifLog *log); 55 56 typedef enum { 57 EXIF_LOG_CODE_NONE, 58 EXIF_LOG_CODE_DEBUG, 59 EXIF_LOG_CODE_NO_MEMORY, 60 EXIF_LOG_CODE_CORRUPT_DATA 61 } ExifLogCode; 62 63 /*! Return a textual description of the given class of error log. 64 * 65 * \param[in] code logging message class 66 * \return textual description of the log class, or NULL if unknown 67 */ 68 const char *exif_log_code_get_title (ExifLogCode code); 69 70 /*! Return a verbose description of the given class of error log. 71 * 72 * \param[in] code logging message class 73 * \return verbose description of the log class, or NULL if unknown 74 */ 75 const char *exif_log_code_get_message (ExifLogCode code); 76 77 /*! Log callback function prototype. 78 */ 79 typedef void (* ExifLogFunc) (ExifLog *log, ExifLogCode, const char *domain, 80 const char *format, va_list args, void *data); 81 82 /*! Register log callback function. 83 * Calls to the log callback function are purely for diagnostic purposes. 84 * 85 * \param[in] log logging state variable 86 * \param[in] func callback function to set 87 * \param[in] data data to pass into callback function 88 */ 89 void exif_log_set_func (ExifLog *log, ExifLogFunc func, void *data); 90 91 #ifndef NO_VERBOSE_TAG_STRINGS 92 void exif_log (ExifLog *log, ExifLogCode, const char *domain, 93 const char *format, ...) 94 #ifdef __GNUC__ 95 __attribute__((__format__(printf,4,5))) 96 #endif 97 ; 98 #else 99 #if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L 100 #define exif_log(...) do { } while (0) 101 #elif defined(__GNUC__) 102 #define exif_log(x...) do { } while (0) 103 #else 104 #define exif_log (void) 105 #endif 106 #endif 107 108 void exif_logv (ExifLog *log, ExifLogCode, const char *domain, 109 const char *format, va_list args); 110 111 /* For your convenience */ 112 #define EXIF_LOG_NO_MEMORY(l,d,s) exif_log ((l), EXIF_LOG_CODE_NO_MEMORY, (d), "Could not allocate %lu byte(s).", (unsigned long)(s)) 113 114 #ifdef __cplusplus 115 } 116 #endif /* __cplusplus */ 117 118 #endif /* !defined(LIBEXIF_EXIF_LOG_H) */ 119