FFmpeg
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 #if FF_API_CHILD_CLASS_NEXT
116  /**
117  * Return an AVClass corresponding to the next potential
118  * AVOptions-enabled child.
119  *
120  * The difference between child_next and this is that
121  * child_next iterates over _already existing_ objects, while
122  * child_class_next iterates over _all possible_ children.
123  */
125  const struct AVClass* (*child_class_next)(const struct AVClass *prev);
126 #endif
127 
128  /**
129  * Category used for visualization (like color)
130  * This is only set if the category is equal for all objects using this class.
131  * available since version (51 << 16 | 56 << 8 | 100)
132  */
134 
135  /**
136  * Callback to return the category.
137  * available since version (51 << 16 | 59 << 8 | 100)
138  */
140 
141  /**
142  * Callback to return the supported/allowed ranges.
143  * available since version (52.12)
144  */
145  int (*query_ranges)(struct AVOptionRanges **, void *obj, const char *key, int flags);
146 
147  /**
148  * Iterate over the AVClasses corresponding to potential AVOptions-enabled
149  * children.
150  *
151  * @param iter pointer to opaque iteration state. The caller must initialize
152  * *iter to NULL before the first call.
153  * @return AVClass for the next AVOptions-enabled child or NULL if there are
154  * no more such children.
155  *
156  * @note The difference between child_next and this is that child_next
157  * iterates over _already existing_ objects, while child_class_iterate
158  * iterates over _all possible_ children.
159  */
160  const struct AVClass* (*child_class_iterate)(void **iter);
161 } AVClass;
162 
163 /**
164  * @addtogroup lavu_log
165  *
166  * @{
167  *
168  * @defgroup lavu_log_constants Logging Constants
169  *
170  * @{
171  */
172 
173 /**
174  * Print no output.
175  */
176 #define AV_LOG_QUIET -8
177 
178 /**
179  * Something went really wrong and we will crash now.
180  */
181 #define AV_LOG_PANIC 0
182 
183 /**
184  * Something went wrong and recovery is not possible.
185  * For example, no header was found for a format which depends
186  * on headers or an illegal combination of parameters is used.
187  */
188 #define AV_LOG_FATAL 8
189 
190 /**
191  * Something went wrong and cannot losslessly be recovered.
192  * However, not all future data is affected.
193  */
194 #define AV_LOG_ERROR 16
195 
196 /**
197  * Something somehow does not look correct. This may or may not
198  * lead to problems. An example would be the use of '-vstrict -2'.
199  */
200 #define AV_LOG_WARNING 24
201 
202 /**
203  * Standard information.
204  */
205 #define AV_LOG_INFO 32
206 
207 /**
208  * Detailed information.
209  */
210 #define AV_LOG_VERBOSE 40
211 
212 /**
213  * Stuff which is only useful for libav* developers.
214  */
215 #define AV_LOG_DEBUG 48
216 
217 /**
218  * Extremely verbose debugging, useful for libav* development.
219  */
220 #define AV_LOG_TRACE 56
221 
222 #define AV_LOG_MAX_OFFSET (AV_LOG_TRACE - AV_LOG_QUIET)
223 
224 /**
225  * @}
226  */
227 
228 /**
229  * Sets additional colors for extended debugging sessions.
230  * @code
231  av_log(ctx, AV_LOG_DEBUG|AV_LOG_C(134), "Message in purple\n");
232  @endcode
233  * Requires 256color terminal support. Uses outside debugging is not
234  * recommended.
235  */
236 #define AV_LOG_C(x) ((x) << 8)
237 
238 /**
239  * Send the specified message to the log if the level is less than or equal
240  * to the current av_log_level. By default, all logging messages are sent to
241  * stderr. This behavior can be altered by setting a different logging callback
242  * function.
243  * @see av_log_set_callback
244  *
245  * @param avcl A pointer to an arbitrary struct of which the first field is a
246  * pointer to an AVClass struct or NULL if general log.
247  * @param level The importance level of the message expressed using a @ref
248  * lavu_log_constants "Logging Constant".
249  * @param fmt The format string (printf-compatible) that specifies how
250  * subsequent arguments are converted to output.
251  */
252 void av_log(void *avcl, int level, const char *fmt, ...) av_printf_format(3, 4);
253 
254 /**
255  * Send the specified message to the log once with the initial_level and then with
256  * the subsequent_level. By default, all logging messages are sent to
257  * stderr. This behavior can be altered by setting a different logging callback
258  * function.
259  * @see av_log
260  *
261  * @param avcl A pointer to an arbitrary struct of which the first field is a
262  * pointer to an AVClass struct or NULL if general log.
263  * @param initial_level importance level of the message expressed using a @ref
264  * lavu_log_constants "Logging Constant" for the first occurance.
265  * @param subsequent_level importance level of the message expressed using a @ref
266  * lavu_log_constants "Logging Constant" after the first occurance.
267  * @param fmt The format string (printf-compatible) that specifies how
268  * subsequent arguments are converted to output.
269  * @param state a variable to keep trak of if a message has already been printed
270  * this must be initialized to 0 before the first use. The same state
271  * must not be accessed by 2 Threads simultaneously.
272  */
273 void av_log_once(void* avcl, int initial_level, int subsequent_level, int *state, const char *fmt, ...) av_printf_format(5, 6);
274 
275 
276 /**
277  * Send the specified message to the log if the level is less than or equal
278  * to the current av_log_level. By default, all logging messages are sent to
279  * stderr. This behavior can be altered by setting a different logging callback
280  * function.
281  * @see av_log_set_callback
282  *
283  * @param avcl A pointer to an arbitrary struct of which the first field is a
284  * pointer to an AVClass struct.
285  * @param level The importance level of the message expressed using a @ref
286  * lavu_log_constants "Logging Constant".
287  * @param fmt The format string (printf-compatible) that specifies how
288  * subsequent arguments are converted to output.
289  * @param vl The arguments referenced by the format string.
290  */
291 void av_vlog(void *avcl, int level, const char *fmt, va_list vl);
292 
293 /**
294  * Get the current log level
295  *
296  * @see lavu_log_constants
297  *
298  * @return Current log level
299  */
300 int av_log_get_level(void);
301 
302 /**
303  * Set the log level
304  *
305  * @see lavu_log_constants
306  *
307  * @param level Logging level
308  */
309 void av_log_set_level(int level);
310 
311 /**
312  * Set the logging callback
313  *
314  * @note The callback must be thread safe, even if the application does not use
315  * threads itself as some codecs are multithreaded.
316  *
317  * @see av_log_default_callback
318  *
319  * @param callback A logging function with a compatible signature.
320  */
321 void av_log_set_callback(void (*callback)(void*, int, const char*, va_list));
322 
323 /**
324  * Default logging callback
325  *
326  * It prints the message to stderr, optionally colorizing it.
327  *
328  * @param avcl A pointer to an arbitrary struct of which the first field is a
329  * pointer to an AVClass struct.
330  * @param level The importance level of the message expressed using a @ref
331  * lavu_log_constants "Logging Constant".
332  * @param fmt The format string (printf-compatible) that specifies how
333  * subsequent arguments are converted to output.
334  * @param vl The arguments referenced by the format string.
335  */
336 void av_log_default_callback(void *avcl, int level, const char *fmt,
337  va_list vl);
338 
339 /**
340  * Return the context name
341  *
342  * @param ctx The AVClass context
343  *
344  * @return The AVClass class_name
345  */
346 const char* av_default_item_name(void* ctx);
348 
349 /**
350  * Format a line of log the same way as the default callback.
351  * @param line buffer to receive the formatted line
352  * @param line_size size of the buffer
353  * @param print_prefix used to store whether the prefix must be printed;
354  * must point to a persistent integer initially set to 1
355  */
356 void av_log_format_line(void *ptr, int level, const char *fmt, va_list vl,
357  char *line, int line_size, int *print_prefix);
358 
359 /**
360  * Format a line of log the same way as the default callback.
361  * @param line buffer to receive the formatted line;
362  * may be NULL if line_size is 0
363  * @param line_size size of the buffer; at most line_size-1 characters will
364  * be written to the buffer, plus one null terminator
365  * @param print_prefix used to store whether the prefix must be printed;
366  * must point to a persistent integer initially set to 1
367  * @return Returns a negative value if an error occurred, otherwise returns
368  * the number of characters that would have been written for a
369  * sufficiently large buffer, not including the terminating null
370  * character. If the return value is not less than line_size, it means
371  * that the log message was truncated to fit the buffer.
372  */
373 int av_log_format_line2(void *ptr, int level, const char *fmt, va_list vl,
374  char *line, int line_size, int *print_prefix);
375 
376 /**
377  * Skip repeated messages, this requires the user app to use av_log() instead of
378  * (f)printf as the 2 would otherwise interfere and lead to
379  * "Last message repeated x times" messages below (f)printf messages with some
380  * bad luck.
381  * Also to receive the last, "last repeated" line if any, the user app must
382  * call av_log(NULL, AV_LOG_QUIET, "%s", ""); at the end
383  */
384 #define AV_LOG_SKIP_REPEATED 1
385 
386 /**
387  * Include the log severity in messages originating from codecs.
388  *
389  * Results in messages such as:
390  * [rawvideo @ 0xDEADBEEF] [error] encode did not produce valid pts
391  */
392 #define AV_LOG_PRINT_LEVEL 2
393 
394 void av_log_set_flags(int arg);
395 int av_log_get_flags(void);
396 
397 /**
398  * @}
399  */
400 
401 #endif /* AVUTIL_LOG_H */
AVOption.
Definition: opt.h:248
void av_log_set_level(int level)
Set the log level.
Definition: log.c:440
const char * av_default_item_name(void *ctx)
Return the context name.
Definition: log.c:235
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
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:328
int(* query_ranges)(struct AVOptionRanges **, void *obj, const char *key, int flags)
Callback to return the supported/allowed ranges.
Definition: log.h:145
void 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:424
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:435
AVClassCategory category
Category used for visualization (like color) This is only set if the category is equal for all object...
Definition: log.h:133
Libavutil version macros.
void av_log_default_callback(void *avcl, int level, const char *fmt, va_list vl)
Default logging callback.
Definition: log.c:346
#define av_printf_format(fmtpos, attrpos)
Definition: attributes.h:161
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:334
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:455
not part of ABI/API
Definition: log.h:47
AVFormatContext * ctx
Definition: movenc.c:48
static struct @318 state
int av_log_get_flags(void)
Definition: log.c:450
Describe the class of an AVClass context structure.
Definition: log.h:67
#define flags(name, subs,...)
Definition: cbs_av1.c:560
uint8_t level
Definition: svq3.c:209
#define attribute_deprecated
Definition: attributes.h:100
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:333
AVClassCategory av_default_get_category(void *ptr)
Definition: log.c:240
AVClassCategory
Definition: log.h:29
void av_log_set_flags(int arg)
Definition: log.c:445
AVClassCategory(* get_category)(void *ctx)
Callback to return the category.
Definition: log.h:139
void void av_log_once(void *avcl, int initial_level, int subsequent_level, int *state, const char *fmt,...) av_printf_format(5
Send the specified message to the log once with the initial_level and then with the subsequent_level...