1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20*/
21
22/**
23 * # CategoryLog
24 *
25 * Simple log messages with priorities and categories. A message's
26 * SDL_LogPriority signifies how important the message is. A message's
27 * SDL_LogCategory signifies from what domain it belongs to. Every category
28 * has a minimum priority specified: when a message belongs to that category,
29 * it will only be sent out if it has that minimum priority or higher.
30 *
31 * SDL's own logs are sent below the default priority threshold, so they are
32 * quiet by default.
33 *
34 * You can change the log verbosity programmatically using
35 * SDL_SetLogPriority() or with SDL_SetHint(SDL_HINT_LOGGING, ...), or with
36 * the "SDL_LOGGING" environment variable. This variable is a comma separated
37 * set of category=level tokens that define the default logging levels for SDL
38 * applications.
39 *
40 * The category can be a numeric category, one of "app", "error", "assert",
41 * "system", "audio", "video", "render", "input", "test", or `*` for any
42 * unspecified category.
43 *
44 * The level can be a numeric level, one of "trace", "verbose", "debug",
45 * "info", "warn", "error", "critical", or "quiet" to disable that category.
46 *
47 * You can omit the category if you want to set the logging level for all
48 * categories.
49 *
50 * If this hint isn't set, the default log levels are equivalent to:
51 *
52 * `app=info,assert=warn,test=verbose,*=error`
53 *
54 * Here's where the messages go on different platforms:
55 *
56 * - Windows: debug output stream
57 * - Android: log output
58 * - Others: standard error output (stderr)
59 *
60 * You don't need to have a newline (`\n`) on the end of messages, the
61 * functions will do that for you. For consistent behavior cross-platform, you
62 * shouldn't have any newlines in messages, such as to log multiple lines in
63 * one call; unusual platform-specific behavior can be observed in such usage.
64 * Do one log call per line instead, with no newlines in messages.
65 *
66 * Each log call is atomic, so you won't see log messages cut off one another
67 * when logging from multiple threads.
68 */
69
70#ifndef SDL_log_h_
71#define SDL_log_h_
72
73#include <SDL3/SDL_stdinc.h>
74
75#include <SDL3/SDL_begin_code.h>
76/* Set up for C function definitions, even when using C++ */
77#ifdef __cplusplus
78extern "C" {
79#endif
80
81/**
82 * The predefined log categories
83 *
84 * By default the application and gpu categories are enabled at the INFO
85 * level, the assert category is enabled at the WARN level, test is enabled at
86 * the VERBOSE level and all other categories are enabled at the ERROR level.
87 *
88 * \since This enum is available since SDL 3.2.0.
89 */
90typedef enum SDL_LogCategory
91{
92 SDL_LOG_CATEGORY_APPLICATION,
93 SDL_LOG_CATEGORY_ERROR,
94 SDL_LOG_CATEGORY_ASSERT,
95 SDL_LOG_CATEGORY_SYSTEM,
96 SDL_LOG_CATEGORY_AUDIO,
97 SDL_LOG_CATEGORY_VIDEO,
98 SDL_LOG_CATEGORY_RENDER,
99 SDL_LOG_CATEGORY_INPUT,
100 SDL_LOG_CATEGORY_TEST,
101 SDL_LOG_CATEGORY_GPU,
102
103 /* Reserved for future SDL library use */
104 SDL_LOG_CATEGORY_RESERVED2,
105 SDL_LOG_CATEGORY_RESERVED3,
106 SDL_LOG_CATEGORY_RESERVED4,
107 SDL_LOG_CATEGORY_RESERVED5,
108 SDL_LOG_CATEGORY_RESERVED6,
109 SDL_LOG_CATEGORY_RESERVED7,
110 SDL_LOG_CATEGORY_RESERVED8,
111 SDL_LOG_CATEGORY_RESERVED9,
112 SDL_LOG_CATEGORY_RESERVED10,
113
114 /* Beyond this point is reserved for application use, e.g.
115 enum {
116 MYAPP_CATEGORY_AWESOME1 = SDL_LOG_CATEGORY_CUSTOM,
117 MYAPP_CATEGORY_AWESOME2,
118 MYAPP_CATEGORY_AWESOME3,
119 ...
120 };
121 */
122 SDL_LOG_CATEGORY_CUSTOM
123} SDL_LogCategory;
124
125/**
126 * The predefined log priorities
127 *
128 * \since This enum is available since SDL 3.2.0.
129 */
130typedef enum SDL_LogPriority
131{
132 SDL_LOG_PRIORITY_INVALID,
133 SDL_LOG_PRIORITY_TRACE,
134 SDL_LOG_PRIORITY_VERBOSE,
135 SDL_LOG_PRIORITY_DEBUG,
136 SDL_LOG_PRIORITY_INFO,
137 SDL_LOG_PRIORITY_WARN,
138 SDL_LOG_PRIORITY_ERROR,
139 SDL_LOG_PRIORITY_CRITICAL,
140 SDL_LOG_PRIORITY_COUNT
141} SDL_LogPriority;
142
143
144/**
145 * Set the priority of all log categories.
146 *
147 * \param priority the SDL_LogPriority to assign.
148 *
149 * \threadsafety It is safe to call this function from any thread.
150 *
151 * \since This function is available since SDL 3.2.0.
152 *
153 * \sa SDL_ResetLogPriorities
154 * \sa SDL_SetLogPriority
155 */
156extern SDL_DECLSPEC void SDLCALL SDL_SetLogPriorities(SDL_LogPriority priority);
157
158/**
159 * Set the priority of a particular log category.
160 *
161 * \param category the category to assign a priority to.
162 * \param priority the SDL_LogPriority to assign.
163 *
164 * \threadsafety It is safe to call this function from any thread.
165 *
166 * \since This function is available since SDL 3.2.0.
167 *
168 * \sa SDL_GetLogPriority
169 * \sa SDL_ResetLogPriorities
170 * \sa SDL_SetLogPriorities
171 */
172extern SDL_DECLSPEC void SDLCALL SDL_SetLogPriority(int category, SDL_LogPriority priority);
173
174/**
175 * Get the priority of a particular log category.
176 *
177 * \param category the category to query.
178 * \returns the SDL_LogPriority for the requested category.
179 *
180 * \threadsafety It is safe to call this function from any thread.
181 *
182 * \since This function is available since SDL 3.2.0.
183 *
184 * \sa SDL_SetLogPriority
185 */
186extern SDL_DECLSPEC SDL_LogPriority SDLCALL SDL_GetLogPriority(int category);
187
188/**
189 * Reset all priorities to default.
190 *
191 * This is called by SDL_Quit().
192 *
193 * \threadsafety It is safe to call this function from any thread.
194 *
195 * \since This function is available since SDL 3.2.0.
196 *
197 * \sa SDL_SetLogPriorities
198 * \sa SDL_SetLogPriority
199 */
200extern SDL_DECLSPEC void SDLCALL SDL_ResetLogPriorities(void);
201
202/**
203 * Set the text prepended to log messages of a given priority.
204 *
205 * By default SDL_LOG_PRIORITY_INFO and below have no prefix, and
206 * SDL_LOG_PRIORITY_WARN and higher have a prefix showing their priority, e.g.
207 * "WARNING: ".
208 *
209 * \param priority the SDL_LogPriority to modify.
210 * \param prefix the prefix to use for that log priority, or NULL to use no
211 * prefix.
212 * \returns true on success or false on failure; call SDL_GetError() for more
213 * information.
214 *
215 * \threadsafety It is safe to call this function from any thread.
216 *
217 * \since This function is available since SDL 3.2.0.
218 *
219 * \sa SDL_SetLogPriorities
220 * \sa SDL_SetLogPriority
221 */
222extern SDL_DECLSPEC bool SDLCALL SDL_SetLogPriorityPrefix(SDL_LogPriority priority, const char *prefix);
223
224/**
225 * Log a message with SDL_LOG_CATEGORY_APPLICATION and SDL_LOG_PRIORITY_INFO.
226 *
227 * \param fmt a printf() style message format string.
228 * \param ... additional parameters matching % tokens in the `fmt` string, if
229 * any.
230 *
231 * \threadsafety It is safe to call this function from any thread.
232 *
233 * \since This function is available since SDL 3.2.0.
234 *
235 * \sa SDL_LogCritical
236 * \sa SDL_LogDebug
237 * \sa SDL_LogError
238 * \sa SDL_LogInfo
239 * \sa SDL_LogMessage
240 * \sa SDL_LogMessageV
241 * \sa SDL_LogTrace
242 * \sa SDL_LogVerbose
243 * \sa SDL_LogWarn
244 */
245extern SDL_DECLSPEC void SDLCALL SDL_Log(SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(1);
246
247/**
248 * Log a message with SDL_LOG_PRIORITY_TRACE.
249 *
250 * \param category the category of the message.
251 * \param fmt a printf() style message format string.
252 * \param ... additional parameters matching % tokens in the **fmt** string,
253 * if any.
254 *
255 * \threadsafety It is safe to call this function from any thread.
256 *
257 * \since This function is available since SDL 3.2.0.
258 *
259 * \sa SDL_Log
260 * \sa SDL_LogCritical
261 * \sa SDL_LogDebug
262 * \sa SDL_LogError
263 * \sa SDL_LogInfo
264 * \sa SDL_LogMessage
265 * \sa SDL_LogMessageV
266 * \sa SDL_LogTrace
267 * \sa SDL_LogVerbose
268 * \sa SDL_LogWarn
269 */
270extern SDL_DECLSPEC void SDLCALL SDL_LogTrace(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
271
272/**
273 * Log a message with SDL_LOG_PRIORITY_VERBOSE.
274 *
275 * \param category the category of the message.
276 * \param fmt a printf() style message format string.
277 * \param ... additional parameters matching % tokens in the **fmt** string,
278 * if any.
279 *
280 * \threadsafety It is safe to call this function from any thread.
281 *
282 * \since This function is available since SDL 3.2.0.
283 *
284 * \sa SDL_Log
285 * \sa SDL_LogCritical
286 * \sa SDL_LogDebug
287 * \sa SDL_LogError
288 * \sa SDL_LogInfo
289 * \sa SDL_LogMessage
290 * \sa SDL_LogMessageV
291 * \sa SDL_LogWarn
292 */
293extern SDL_DECLSPEC void SDLCALL SDL_LogVerbose(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
294
295/**
296 * Log a message with SDL_LOG_PRIORITY_DEBUG.
297 *
298 * \param category the category of the message.
299 * \param fmt a printf() style message format string.
300 * \param ... additional parameters matching % tokens in the **fmt** string,
301 * if any.
302 *
303 * \threadsafety It is safe to call this function from any thread.
304 *
305 * \since This function is available since SDL 3.2.0.
306 *
307 * \sa SDL_Log
308 * \sa SDL_LogCritical
309 * \sa SDL_LogError
310 * \sa SDL_LogInfo
311 * \sa SDL_LogMessage
312 * \sa SDL_LogMessageV
313 * \sa SDL_LogTrace
314 * \sa SDL_LogVerbose
315 * \sa SDL_LogWarn
316 */
317extern SDL_DECLSPEC void SDLCALL SDL_LogDebug(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
318
319/**
320 * Log a message with SDL_LOG_PRIORITY_INFO.
321 *
322 * \param category the category of the message.
323 * \param fmt a printf() style message format string.
324 * \param ... additional parameters matching % tokens in the **fmt** string,
325 * if any.
326 *
327 * \threadsafety It is safe to call this function from any thread.
328 *
329 * \since This function is available since SDL 3.2.0.
330 *
331 * \sa SDL_Log
332 * \sa SDL_LogCritical
333 * \sa SDL_LogDebug
334 * \sa SDL_LogError
335 * \sa SDL_LogMessage
336 * \sa SDL_LogMessageV
337 * \sa SDL_LogTrace
338 * \sa SDL_LogVerbose
339 * \sa SDL_LogWarn
340 */
341extern SDL_DECLSPEC void SDLCALL SDL_LogInfo(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
342
343/**
344 * Log a message with SDL_LOG_PRIORITY_WARN.
345 *
346 * \param category the category of the message.
347 * \param fmt a printf() style message format string.
348 * \param ... additional parameters matching % tokens in the **fmt** string,
349 * if any.
350 *
351 * \threadsafety It is safe to call this function from any thread.
352 *
353 * \since This function is available since SDL 3.2.0.
354 *
355 * \sa SDL_Log
356 * \sa SDL_LogCritical
357 * \sa SDL_LogDebug
358 * \sa SDL_LogError
359 * \sa SDL_LogInfo
360 * \sa SDL_LogMessage
361 * \sa SDL_LogMessageV
362 * \sa SDL_LogTrace
363 * \sa SDL_LogVerbose
364 */
365extern SDL_DECLSPEC void SDLCALL SDL_LogWarn(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
366
367/**
368 * Log a message with SDL_LOG_PRIORITY_ERROR.
369 *
370 * \param category the category of the message.
371 * \param fmt a printf() style message format string.
372 * \param ... additional parameters matching % tokens in the **fmt** string,
373 * if any.
374 *
375 * \threadsafety It is safe to call this function from any thread.
376 *
377 * \since This function is available since SDL 3.2.0.
378 *
379 * \sa SDL_Log
380 * \sa SDL_LogCritical
381 * \sa SDL_LogDebug
382 * \sa SDL_LogInfo
383 * \sa SDL_LogMessage
384 * \sa SDL_LogMessageV
385 * \sa SDL_LogTrace
386 * \sa SDL_LogVerbose
387 * \sa SDL_LogWarn
388 */
389extern SDL_DECLSPEC void SDLCALL SDL_LogError(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
390
391/**
392 * Log a message with SDL_LOG_PRIORITY_CRITICAL.
393 *
394 * \param category the category of the message.
395 * \param fmt a printf() style message format string.
396 * \param ... additional parameters matching % tokens in the **fmt** string,
397 * if any.
398 *
399 * \threadsafety It is safe to call this function from any thread.
400 *
401 * \since This function is available since SDL 3.2.0.
402 *
403 * \sa SDL_Log
404 * \sa SDL_LogDebug
405 * \sa SDL_LogError
406 * \sa SDL_LogInfo
407 * \sa SDL_LogMessage
408 * \sa SDL_LogMessageV
409 * \sa SDL_LogTrace
410 * \sa SDL_LogVerbose
411 * \sa SDL_LogWarn
412 */
413extern SDL_DECLSPEC void SDLCALL SDL_LogCritical(int category, SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(2);
414
415/**
416 * Log a message with the specified category and priority.
417 *
418 * \param category the category of the message.
419 * \param priority the priority of the message.
420 * \param fmt a printf() style message format string.
421 * \param ... additional parameters matching % tokens in the **fmt** string,
422 * if any.
423 *
424 * \threadsafety It is safe to call this function from any thread.
425 *
426 * \since This function is available since SDL 3.2.0.
427 *
428 * \sa SDL_Log
429 * \sa SDL_LogCritical
430 * \sa SDL_LogDebug
431 * \sa SDL_LogError
432 * \sa SDL_LogInfo
433 * \sa SDL_LogMessageV
434 * \sa SDL_LogTrace
435 * \sa SDL_LogVerbose
436 * \sa SDL_LogWarn
437 */
438extern SDL_DECLSPEC void SDLCALL SDL_LogMessage(int category,
439 SDL_LogPriority priority,
440 SDL_PRINTF_FORMAT_STRING const char *fmt, ...) SDL_PRINTF_VARARG_FUNC(3);
441
442/**
443 * Log a message with the specified category and priority.
444 *
445 * \param category the category of the message.
446 * \param priority the priority of the message.
447 * \param fmt a printf() style message format string.
448 * \param ap a variable argument list.
449 *
450 * \threadsafety It is safe to call this function from any thread.
451 *
452 * \since This function is available since SDL 3.2.0.
453 *
454 * \sa SDL_Log
455 * \sa SDL_LogCritical
456 * \sa SDL_LogDebug
457 * \sa SDL_LogError
458 * \sa SDL_LogInfo
459 * \sa SDL_LogMessage
460 * \sa SDL_LogTrace
461 * \sa SDL_LogVerbose
462 * \sa SDL_LogWarn
463 */
464extern SDL_DECLSPEC void SDLCALL SDL_LogMessageV(int category,
465 SDL_LogPriority priority,
466 SDL_PRINTF_FORMAT_STRING const char *fmt, va_list ap) SDL_PRINTF_VARARG_FUNCV(3);
467
468/**
469 * The prototype for the log output callback function.
470 *
471 * This function is called by SDL when there is new text to be logged. A mutex
472 * is held so that this function is never called by more than one thread at
473 * once.
474 *
475 * \param userdata what was passed as `userdata` to
476 * SDL_SetLogOutputFunction().
477 * \param category the category of the message.
478 * \param priority the priority of the message.
479 * \param message the message being output.
480 *
481 * \since This datatype is available since SDL 3.2.0.
482 */
483typedef void (SDLCALL *SDL_LogOutputFunction)(void *userdata, int category, SDL_LogPriority priority, const char *message);
484
485/**
486 * Get the default log output function.
487 *
488 * \returns the default log output callback.
489 *
490 * \threadsafety It is safe to call this function from any thread.
491 *
492 * \since This function is available since SDL 3.2.0.
493 *
494 * \sa SDL_SetLogOutputFunction
495 * \sa SDL_GetLogOutputFunction
496 */
497extern SDL_DECLSPEC SDL_LogOutputFunction SDLCALL SDL_GetDefaultLogOutputFunction(void);
498
499/**
500 * Get the current log output function.
501 *
502 * \param callback an SDL_LogOutputFunction filled in with the current log
503 * callback.
504 * \param userdata a pointer filled in with the pointer that is passed to
505 * `callback`.
506 *
507 * \threadsafety It is safe to call this function from any thread.
508 *
509 * \since This function is available since SDL 3.2.0.
510 *
511 * \sa SDL_GetDefaultLogOutputFunction
512 * \sa SDL_SetLogOutputFunction
513 */
514extern SDL_DECLSPEC void SDLCALL SDL_GetLogOutputFunction(SDL_LogOutputFunction *callback, void **userdata);
515
516/**
517 * Replace the default log output function with one of your own.
518 *
519 * \param callback an SDL_LogOutputFunction to call instead of the default.
520 * \param userdata a pointer that is passed to `callback`.
521 *
522 * \threadsafety It is safe to call this function from any thread.
523 *
524 * \since This function is available since SDL 3.2.0.
525 *
526 * \sa SDL_GetDefaultLogOutputFunction
527 * \sa SDL_GetLogOutputFunction
528 */
529extern SDL_DECLSPEC void SDLCALL SDL_SetLogOutputFunction(SDL_LogOutputFunction callback, void *userdata);
530
531
532/* Ends C function definitions when using C++ */
533#ifdef __cplusplus
534}
535#endif
536#include <SDL3/SDL_close_code.h>
537
538#endif /* SDL_log_h_ */
539