log.h (5388B)
1 /* 2 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> 3 * 4 * This file is part of Libav. 5 * 6 * Libav is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * Libav is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with Libav; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21 #ifndef AVUTIL_LOG_H 22 #define AVUTIL_LOG_H 23 24 #include <stdarg.h> 25 #include "avutil.h" 26 #include "attributes.h" 27 28 /** 29 * Describe the class of an AVClass context structure. That is an 30 * arbitrary struct of which the first field is a pointer to an 31 * AVClass struct (e.g. AVCodecContext, AVFormatContext etc.). 32 */ 33 typedef struct AVClass { 34 /** 35 * The name of the class; usually it is the same name as the 36 * context structure type to which the AVClass is associated. 37 */ 38 const char* class_name; 39 40 /** 41 * A pointer to a function which returns the name of a context 42 * instance ctx associated with the class. 43 */ 44 const char* (*item_name)(void* ctx); 45 46 /** 47 * a pointer to the first option specified in the class if any or NULL 48 * 49 * @see av_set_default_options() 50 */ 51 const struct AVOption *option; 52 53 /** 54 * LIBAVUTIL_VERSION with which this structure was created. 55 * This is used to allow fields to be added without requiring major 56 * version bumps everywhere. 57 */ 58 59 int version; 60 61 /** 62 * Offset in the structure where log_level_offset is stored. 63 * 0 means there is no such variable 64 */ 65 int log_level_offset_offset; 66 67 /** 68 * Offset in the structure where a pointer to the parent context for loging is stored. 69 * for example a decoder that uses eval.c could pass its AVCodecContext to eval as such 70 * parent context. And a av_log() implementation could then display the parent context 71 * can be NULL of course 72 */ 73 int parent_log_context_offset; 74 75 /** 76 * Return next AVOptions-enabled child or NULL 77 */ 78 void* (*child_next)(void *obj, void *prev); 79 80 /** 81 * Return an AVClass corresponding to next potential 82 * AVOptions-enabled child. 83 * 84 * The difference between child_next and this is that 85 * child_next iterates over _already existing_ objects, while 86 * child_class_next iterates over _all possible_ children. 87 */ 88 const struct AVClass* (*child_class_next)(const struct AVClass *prev); 89 } AVClass; 90 91 /* av_log API */ 92 93 #define AV_LOG_QUIET -8 94 95 /** 96 * Something went really wrong and we will crash now. 97 */ 98 #define AV_LOG_PANIC 0 99 100 /** 101 * Something went wrong and recovery is not possible. 102 * For example, no header was found for a format which depends 103 * on headers or an illegal combination of parameters is used. 104 */ 105 #define AV_LOG_FATAL 8 106 107 /** 108 * Something went wrong and cannot losslessly be recovered. 109 * However, not all future data is affected. 110 */ 111 #define AV_LOG_ERROR 16 112 113 /** 114 * Something somehow does not look correct. This may or may not 115 * lead to problems. An example would be the use of '-vstrict -2'. 116 */ 117 #define AV_LOG_WARNING 24 118 119 #define AV_LOG_INFO 32 120 #define AV_LOG_VERBOSE 40 121 122 /** 123 * Stuff which is only useful for libav* developers. 124 */ 125 #define AV_LOG_DEBUG 48 126 127 /** 128 * Send the specified message to the log if the level is less than or equal 129 * to the current av_log_level. By default, all logging messages are sent to 130 * stderr. This behavior can be altered by setting a different av_vlog callback 131 * function. 132 * 133 * @param avcl A pointer to an arbitrary struct of which the first field is a 134 * pointer to an AVClass struct. 135 * @param level The importance level of the message, lower values signifying 136 * higher importance. 137 * @param fmt The format string (printf-compatible) that specifies how 138 * subsequent arguments are converted to output. 139 * @see av_vlog 140 */ 141 void av_log(void *avcl, int level, const char *fmt, ...) av_printf_format(3, 4); 142 143 void av_vlog(void *avcl, int level, const char *fmt, va_list); 144 int av_log_get_level(void); 145 void av_log_set_level(int); 146 void av_log_set_callback(void (*)(void*, int, const char*, va_list)); 147 void av_log_default_callback(void* ptr, int level, const char* fmt, va_list vl); 148 const char* av_default_item_name(void* ctx); 149 150 /** 151 * av_dlog macros 152 * Useful to print debug messages that shouldn't get compiled in normally. 153 */ 154 155 #ifdef DEBUG 156 # define av_dlog(pctx, ...) av_log(pctx, AV_LOG_DEBUG, __VA_ARGS__) 157 #else 158 # define av_dlog(pctx, ...) 159 #endif 160 161 /** 162 * Skip repeated messages, this requires the user app to use av_log() instead of 163 * (f)printf as the 2 would otherwise interfere and lead to 164 * "Last message repeated x times" messages below (f)printf messages with some 165 * bad luck. 166 * Also to receive the last, "last repeated" line if any, the user app must 167 * call av_log(NULL, AV_LOG_QUIET, ""); at the end 168 */ 169 #define AV_LOG_SKIP_REPEATED 1 170 void av_log_set_flags(int arg); 171 172 #endif /* AVUTIL_LOG_H */