FFmpeg  4.0
log.h
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1 /*
2  * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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 #include "version.h"
28 
29 typedef enum {
47  AV_CLASS_CATEGORY_NB ///< not part of ABI/API
49 
50 #define AV_IS_INPUT_DEVICE(category) \
51  (((category) == AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT) || \
52  ((category) == AV_CLASS_CATEGORY_DEVICE_AUDIO_INPUT) || \
53  ((category) == AV_CLASS_CATEGORY_DEVICE_INPUT))
54 
55 #define AV_IS_OUTPUT_DEVICE(category) \
56  (((category) == AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT) || \
57  ((category) == AV_CLASS_CATEGORY_DEVICE_AUDIO_OUTPUT) || \
58  ((category) == AV_CLASS_CATEGORY_DEVICE_OUTPUT))
59 
60 struct AVOptionRanges;
61 
62 /**
63  * Describe the class of an AVClass context structure. That is an
64  * arbitrary struct of which the first field is a pointer to an
65  * AVClass struct (e.g. AVCodecContext, AVFormatContext etc.).
66  */
67 typedef struct AVClass {
68  /**
69  * The name of the class; usually it is the same name as the
70  * context structure type to which the AVClass is associated.
71  */
72  const char* class_name;
73 
74  /**
75  * A pointer to a function which returns the name of a context
76  * instance ctx associated with the class.
77  */
78  const char* (*item_name)(void* ctx);
79 
80  /**
81  * a pointer to the first option specified in the class if any or NULL
82  *
83  * @see av_set_default_options()
84  */
85  const struct AVOption *option;
86 
87  /**
88  * LIBAVUTIL_VERSION with which this structure was created.
89  * This is used to allow fields to be added without requiring major
90  * version bumps everywhere.
91  */
92 
93  int version;
94 
95  /**
96  * Offset in the structure where log_level_offset is stored.
97  * 0 means there is no such variable
98  */
100 
101  /**
102  * Offset in the structure where a pointer to the parent context for
103  * logging is stored. For example a decoder could pass its AVCodecContext
104  * to eval as such a parent context, which an av_log() implementation
105  * could then leverage to display the parent context.
106  * The offset can be NULL.
107  */
109 
110  /**
111  * Return next AVOptions-enabled child or NULL
112  */
113  void* (*child_next)(void *obj, void *prev);
114 
115  /**
116  * Return an AVClass corresponding to the next potential
117  * AVOptions-enabled child.
118  *
119  * The difference between child_next and this is that
120  * child_next iterates over _already existing_ objects, while
121  * child_class_next iterates over _all possible_ children.
122  */
123  const struct AVClass* (*child_class_next)(const struct AVClass *prev);
124 
125  /**
126  * Category used for visualization (like color)
127  * This is only set if the category is equal for all objects using this class.
128  * available since version (51 << 16 | 56 << 8 | 100)
129  */
131 
132  /**
133  * Callback to return the category.
134  * available since version (51 << 16 | 59 << 8 | 100)
135  */
137 
138  /**
139  * Callback to return the supported/allowed ranges.
140  * available since version (52.12)
141  */
142  int (*query_ranges)(struct AVOptionRanges **, void *obj, const char *key, int flags);
143 } AVClass;
144 
145 /**
146  * @addtogroup lavu_log
147  *
148  * @{
149  *
150  * @defgroup lavu_log_constants Logging Constants
151  *
152  * @{
153  */
154 
155 /**
156  * Print no output.
157  */
158 #define AV_LOG_QUIET -8
159 
160 /**
161  * Something went really wrong and we will crash now.
162  */
163 #define AV_LOG_PANIC 0
164 
165 /**
166  * Something went wrong and recovery is not possible.
167  * For example, no header was found for a format which depends
168  * on headers or an illegal combination of parameters is used.
169  */
170 #define AV_LOG_FATAL 8
171 
172 /**
173  * Something went wrong and cannot losslessly be recovered.
174  * However, not all future data is affected.
175  */
176 #define AV_LOG_ERROR 16
177 
178 /**
179  * Something somehow does not look correct. This may or may not
180  * lead to problems. An example would be the use of '-vstrict -2'.
181  */
182 #define AV_LOG_WARNING 24
183 
184 /**
185  * Standard information.
186  */
187 #define AV_LOG_INFO 32
188 
189 /**
190  * Detailed information.
191  */
192 #define AV_LOG_VERBOSE 40
193 
194 /**
195  * Stuff which is only useful for libav* developers.
196  */
197 #define AV_LOG_DEBUG 48
198 
199 /**
200  * Extremely verbose debugging, useful for libav* development.
201  */
202 #define AV_LOG_TRACE 56
203 
204 #define AV_LOG_MAX_OFFSET (AV_LOG_TRACE - AV_LOG_QUIET)
205 
206 /**
207  * @}
208  */
209 
210 /**
211  * Sets additional colors for extended debugging sessions.
212  * @code
213  av_log(ctx, AV_LOG_DEBUG|AV_LOG_C(134), "Message in purple\n");
214  @endcode
215  * Requires 256color terminal support. Uses outside debugging is not
216  * recommended.
217  */
218 #define AV_LOG_C(x) ((x) << 8)
219 
220 /**
221  * Send the specified message to the log if the level is less than or equal
222  * to the current av_log_level. By default, all logging messages are sent to
223  * stderr. This behavior can be altered by setting a different logging callback
224  * function.
225  * @see av_log_set_callback
226  *
227  * @param avcl A pointer to an arbitrary struct of which the first field is a
228  * pointer to an AVClass struct or NULL if general log.
229  * @param level The importance level of the message expressed using a @ref
230  * lavu_log_constants "Logging Constant".
231  * @param fmt The format string (printf-compatible) that specifies how
232  * subsequent arguments are converted to output.
233  */
234 void av_log(void *avcl, int level, const char *fmt, ...) av_printf_format(3, 4);
235 
236 
237 /**
238  * Send the specified message to the log if the level is less than or equal
239  * to the current av_log_level. By default, all logging messages are sent to
240  * stderr. This behavior can be altered by setting a different logging callback
241  * function.
242  * @see av_log_set_callback
243  *
244  * @param avcl A pointer to an arbitrary struct of which the first field is a
245  * pointer to an AVClass struct.
246  * @param level The importance level of the message expressed using a @ref
247  * lavu_log_constants "Logging Constant".
248  * @param fmt The format string (printf-compatible) that specifies how
249  * subsequent arguments are converted to output.
250  * @param vl The arguments referenced by the format string.
251  */
252 void av_vlog(void *avcl, int level, const char *fmt, va_list vl);
253 
254 /**
255  * Get the current log level
256  *
257  * @see lavu_log_constants
258  *
259  * @return Current log level
260  */
261 int av_log_get_level(void);
262 
263 /**
264  * Set the log level
265  *
266  * @see lavu_log_constants
267  *
268  * @param level Logging level
269  */
270 void av_log_set_level(int level);
271 
272 /**
273  * Set the logging callback
274  *
275  * @note The callback must be thread safe, even if the application does not use
276  * threads itself as some codecs are multithreaded.
277  *
278  * @see av_log_default_callback
279  *
280  * @param callback A logging function with a compatible signature.
281  */
282 void av_log_set_callback(void (*callback)(void*, int, const char*, va_list));
283 
284 /**
285  * Default logging callback
286  *
287  * It prints the message to stderr, optionally colorizing it.
288  *
289  * @param avcl A pointer to an arbitrary struct of which the first field is a
290  * pointer to an AVClass struct.
291  * @param level The importance level of the message expressed using a @ref
292  * lavu_log_constants "Logging Constant".
293  * @param fmt The format string (printf-compatible) that specifies how
294  * subsequent arguments are converted to output.
295  * @param vl The arguments referenced by the format string.
296  */
297 void av_log_default_callback(void *avcl, int level, const char *fmt,
298  va_list vl);
299 
300 /**
301  * Return the context name
302  *
303  * @param ctx The AVClass context
304  *
305  * @return The AVClass class_name
306  */
307 const char* av_default_item_name(void* ctx);
309 
310 /**
311  * Format a line of log the same way as the default callback.
312  * @param line buffer to receive the formatted line
313  * @param line_size size of the buffer
314  * @param print_prefix used to store whether the prefix must be printed;
315  * must point to a persistent integer initially set to 1
316  */
317 void av_log_format_line(void *ptr, int level, const char *fmt, va_list vl,
318  char *line, int line_size, int *print_prefix);
319 
320 /**
321  * Format a line of log the same way as the default callback.
322  * @param line buffer to receive the formatted line;
323  * may be NULL if line_size is 0
324  * @param line_size size of the buffer; at most line_size-1 characters will
325  * be written to the buffer, plus one null terminator
326  * @param print_prefix used to store whether the prefix must be printed;
327  * must point to a persistent integer initially set to 1
328  * @return Returns a negative value if an error occurred, otherwise returns
329  * the number of characters that would have been written for a
330  * sufficiently large buffer, not including the terminating null
331  * character. If the return value is not less than line_size, it means
332  * that the log message was truncated to fit the buffer.
333  */
334 int av_log_format_line2(void *ptr, int level, const char *fmt, va_list vl,
335  char *line, int line_size, int *print_prefix);
336 
337 /**
338  * Skip repeated messages, this requires the user app to use av_log() instead of
339  * (f)printf as the 2 would otherwise interfere and lead to
340  * "Last message repeated x times" messages below (f)printf messages with some
341  * bad luck.
342  * Also to receive the last, "last repeated" line if any, the user app must
343  * call av_log(NULL, AV_LOG_QUIET, "%s", ""); at the end
344  */
345 #define AV_LOG_SKIP_REPEATED 1
346 
347 /**
348  * Include the log severity in messages originating from codecs.
349  *
350  * Results in messages such as:
351  * [rawvideo @ 0xDEADBEEF] [error] encode did not produce valid pts
352  */
353 #define AV_LOG_PRINT_LEVEL 2
354 
355 void av_log_set_flags(int arg);
356 int av_log_get_flags(void);
357 
358 /**
359  * @}
360  */
361 
362 #endif /* AVUTIL_LOG_H */
AVOption.
Definition: opt.h:246
const char * fmt
Definition: avisynth_c.h:769
void av_log_set_level(int level)
Set the log level.
Definition: log.c:385
const char * av_default_item_name(void *ctx)
Return the context name.
Definition: log.c:191
void av_log(void *avcl, int level, const char *fmt,...) av_printf_format(3
Send the specified message to the log if the level is less than or equal to the current av_log_level...
Convenience header that includes libavutil&#39;s core.
const char * key
Macro definitions for various function/variable attributes.
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
const struct AVOption * option
a pointer to the first option specified in the class if any or NULL
Definition: log.h:85
int log_level_offset_offset
Offset in the structure where log_level_offset is stored.
Definition: log.h:99
static int flags
Definition: log.c:55
void av_log_format_line(void *ptr, int level, const char *fmt, va_list vl, char *line, int line_size, int *print_prefix)
Format a line of log the same way as the default callback.
Definition: log.c:282
int(* query_ranges)(struct AVOptionRanges **, void *obj, const char *key, int flags)
Callback to return the supported/allowed ranges.
Definition: log.h:142
const char * arg
Definition: jacosubdec.c:66
Definition: graph2dot.c:48
int av_log_get_level(void)
Get the current log level.
Definition: log.c:380
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:130
Libavutil version macros.
void av_log_default_callback(void *avcl, int level, const char *fmt, va_list vl)
Default logging callback.
Definition: log.c:300
#define av_printf_format(fmtpos, attrpos)
Definition: attributes.h:155
int av_log_format_line2(void *ptr, int level, const char *fmt, va_list vl, char *line, int line_size, int *print_prefix)
Format a line of log the same way as the default callback.
Definition: log.c:288
static void callback(void *priv_data, int index, uint8_t *buf, int buf_size, int64_t time, enum dshowDeviceType devtype)
Definition: dshow.c:161
void av_log_set_callback(void(*callback)(void *, int, const char *, va_list))
Set the logging callback.
Definition: log.c:400
not part of ABI/API
Definition: log.h:47
AVFormatContext * ctx
Definition: movenc.c:48
int av_log_get_flags(void)
Definition: log.c:395
Describe the class of an AVClass context structure.
Definition: log.h:67
void void av_vlog(void *avcl, int level, const char *fmt, va_list vl)
Send the specified message to the log if the level is less than or equal to the current av_log_level...
Definition: log.c:373
uint8_t level
Definition: svq3.c:207
int version
LIBAVUTIL_VERSION with which this structure was created.
Definition: log.h:93
int
int parent_log_context_offset
Offset in the structure where a pointer to the parent context for logging is stored.
Definition: log.h:108
List of AVOptionRange structs.
Definition: opt.h:328
AVClassCategory av_default_get_category(void *ptr)
Definition: log.c:196
AVClassCategory
Definition: log.h:29
void av_log_set_flags(int arg)
Definition: log.c:390
AVClassCategory(* get_category)(void *ctx)
Callback to return the category.
Definition: log.h:136