SDL 3.0
SDL_assert.h
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2026 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 * # CategoryAssert
24 *
25 * A helpful assertion macro!
26 *
27 * SDL assertions operate like your usual `assert` macro, but with some added
28 * features:
29 *
30 * - It uses a trick with the `sizeof` operator, so disabled assertions
31 * vaporize out of the compiled code, but variables only referenced in the
32 * assertion won't trigger compiler warnings about being unused.
33 * - It is safe to use with a dangling-else: `if (x) SDL_assert(y); else
34 * do_something();`
35 * - It works the same everywhere, instead of counting on various platforms'
36 * compiler and C runtime to behave.
37 * - It provides multiple levels of assertion (SDL_assert, SDL_assert_release,
38 * SDL_assert_paranoid) instead of a single all-or-nothing option.
39 * - It offers a variety of responses when an assertion fails (retry, trigger
40 * the debugger, abort the program, ignore the failure once, ignore it for
41 * the rest of the program's run).
42 * - It tries to show the user a dialog by default, if possible, but the app
43 * can provide a callback to handle assertion failures however they like.
44 * - It lets failed assertions be retried. Perhaps you had a network failure
45 * and just want to retry the test after plugging your network cable back
46 * in? You can.
47 * - It lets the user ignore an assertion failure, if there's a harmless
48 * problem that one can continue past.
49 * - It lets the user mark an assertion as ignored for the rest of the
50 * program's run; if there's a harmless problem that keeps popping up.
51 * - It provides statistics and data on all failed assertions to the app.
52 * - It allows the default assertion handler to be controlled with environment
53 * variables, in case an automated script needs to control it.
54 * - It can be used as an aid to Clang's static analysis; it will treat SDL
55 * assertions as universally true (under the assumption that you are serious
56 * about the asserted claims and that your debug builds will detect when
57 * these claims were wrong). This can help the analyzer avoid false
58 * positives.
59 *
60 * To use it: compile a debug build and just sprinkle around tests to check
61 * your code!
62 */
63
64#ifndef SDL_assert_h_
65#define SDL_assert_h_
66
67#include <SDL3/SDL_stdinc.h>
68
69#include <SDL3/SDL_begin_code.h>
70/* Set up for C function definitions, even when using C++ */
71#ifdef __cplusplus
72extern "C" {
73#endif
74
75#ifdef SDL_WIKI_DOCUMENTATION_SECTION
76
77/**
78 * The level of assertion aggressiveness.
79 *
80 * This value changes depending on compiler options and other preprocessor
81 * defines.
82 *
83 * It is currently one of the following values, but future SDL releases might
84 * add more:
85 *
86 * - 0: All SDL assertion macros are disabled.
87 * - 1: Release settings: SDL_assert disabled, SDL_assert_release enabled.
88 * - 2: Debug settings: SDL_assert and SDL_assert_release enabled.
89 * - 3: Paranoid settings: All SDL assertion macros enabled, including
90 * SDL_assert_paranoid.
91 *
92 * \since This macro is available since SDL 3.2.0.
93 */
94#define SDL_ASSERT_LEVEL SomeNumberBasedOnVariousFactors
95
96#elif !defined(SDL_ASSERT_LEVEL)
97#ifdef SDL_DEFAULT_ASSERT_LEVEL
98#define SDL_ASSERT_LEVEL SDL_DEFAULT_ASSERT_LEVEL
99#elif defined(_DEBUG) || defined(DEBUG) || \
100 (defined(__GNUC__) && !defined(__OPTIMIZE__))
101#define SDL_ASSERT_LEVEL 2
102#else
103#define SDL_ASSERT_LEVEL 1
104#endif
105#endif
106
107#ifdef SDL_WIKI_DOCUMENTATION_SECTION
108
109/**
110 * Attempt to tell an attached debugger to pause.
111 *
112 * This allows an app to programmatically halt ("break") the debugger as if it
113 * had hit a breakpoint, allowing the developer to examine program state, etc.
114 *
115 * This is a macro--not a function--so that the debugger breaks on the source
116 * code line that used SDL_TriggerBreakpoint and not in some random guts of
117 * SDL. SDL_assert uses this macro for the same reason.
118 *
119 * If the program is not running under a debugger, SDL_TriggerBreakpoint will
120 * likely terminate the app, possibly without warning. If the current platform
121 * isn't supported, this macro is left undefined.
122 *
123 * \threadsafety It is safe to call this macro from any thread.
124 *
125 * \since This macro is available since SDL 3.2.0.
126 */
127#define SDL_TriggerBreakpoint() TriggerABreakpointInAPlatformSpecificManner
128
129#elif defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER >= 1310)
130 /* Don't include intrin.h here because it contains C++ code */
131 extern void __cdecl __debugbreak(void);
132 #define SDL_TriggerBreakpoint() __debugbreak()
133#elif defined(_MSC_VER) && defined(_M_IX86)
134 #define SDL_TriggerBreakpoint() { _asm { int 0x03 } }
135#elif SDL_HAS_BUILTIN(__builtin_debugtrap)
136 #define SDL_TriggerBreakpoint() __builtin_debugtrap()
137#elif SDL_HAS_BUILTIN(__builtin_trap)
138 #define SDL_TriggerBreakpoint() __builtin_trap()
139#elif (defined(__GNUC__) || defined(__clang__) || defined(__TINYC__) || defined(__slimcc__)) && (defined(__i386__) || defined(__x86_64__))
140 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
141#elif (defined(__GNUC__) || defined(__clang__)) && defined(__riscv)
142 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "ebreak\n\t" )
143#elif ( defined(SDL_PLATFORM_APPLE) && (defined(__arm64__) || defined(__aarch64__)) ) /* this might work on other ARM targets, but this is a known quantity... */
144 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "brk #22\n\t" )
145#elif defined(SDL_PLATFORM_APPLE) && defined(__arm__)
146 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "bkpt #22\n\t" )
147#elif defined(_WIN32) && ((defined(__GNUC__) || defined(__clang__)) && (defined(__arm64__) || defined(__aarch64__)) )
148 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "brk #0xF000\n\t" )
149#elif defined(__GNUC__) || defined(__clang__)
150 #define SDL_TriggerBreakpoint() __builtin_trap() /* older gcc may not support SDL_HAS_BUILTIN(__builtin_trap) above */
151#elif defined(__386__) && defined(__WATCOMC__)
152 #define SDL_TriggerBreakpoint() { _asm { int 0x03 } }
153#elif defined(HAVE_SIGNAL_H) && !defined(__WATCOMC__)
154 #include <signal.h>
155 #define SDL_TriggerBreakpoint() raise(SIGTRAP)
156#else
157 /* SDL_TriggerBreakpoint is intentionally left undefined on unknown platforms. */
158#endif
159
160#ifdef SDL_WIKI_DOCUMENTATION_SECTION
161
162/**
163 * A constant that contains the current function being compiled.
164 *
165 * If SDL can't figure how the compiler reports this, it will use "???".
166 *
167 * \since This macro is available since SDL 3.2.0.
168 */
169#define SDL_FUNCTION __FUNCTION__
170
171#elif !defined(SDL_FUNCTION)
172#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
173# define SDL_FUNCTION __func__
174#elif ((defined(__GNUC__) && (__GNUC__ >= 2)) || defined(_MSC_VER) || defined (__WATCOMC__))
175# define SDL_FUNCTION __FUNCTION__
176#else
177# define SDL_FUNCTION "???"
178#endif
179#endif
180
181#ifdef SDL_WIKI_DOCUMENTATION_SECTION
182
183/**
184 * A macro that reports the current file being compiled.
185 *
186 * This macro is only defined if it isn't already defined, so to override it
187 * (perhaps with something that doesn't provide path information at all, so
188 * build machine information doesn't leak into public binaries), apps can
189 * define this macro before including SDL.h or SDL_assert.h.
190 *
191 * \since This macro is available since SDL 3.2.0.
192 */
193#define SDL_FILE __FILE_NAME__
194
195#elif !defined(SDL_FILE)
196#ifdef __FILE_NAME__
197#define SDL_FILE __FILE_NAME__
198#else
199#define SDL_FILE __FILE__
200#endif
201#endif
202
203#ifdef SDL_WIKI_DOCUMENTATION_SECTION
204
205/**
206 * A macro that reports the current file being compiled, for use in
207 * assertions.
208 *
209 * This macro is only defined if it isn't already defined, so to override it
210 * (perhaps with something that doesn't provide path information at all, so
211 * build machine information doesn't leak into public binaries), apps can
212 * define this macro before including SDL_assert.h. For example, defining this
213 * to `""` will make sure no source path information is included in asserts.
214 *
215 * \since This macro is available since SDL 3.4.0.
216 */
217#define SDL_ASSERT_FILE SDL_FILE
218
219#elif !defined(SDL_ASSERT_FILE)
220#define SDL_ASSERT_FILE SDL_FILE
221#endif
222
223
224/**
225 * A macro that reports the current line number of the file being compiled.
226 *
227 * \since This macro is available since SDL 3.2.0.
228 */
229#define SDL_LINE __LINE__
230
231/*
232sizeof (x) makes the compiler still parse the expression even without
233assertions enabled, so the code is always checked at compile time, but
234doesn't actually generate code for it, so there are no side effects or
235expensive checks at run time, just the constant size of what x WOULD be,
236which presumably gets optimized out as unused.
237This also solves the problem of...
238
239 int somevalue = blah();
240 SDL_assert(somevalue == 1);
241
242...which would cause compiles to complain that somevalue is unused if we
243disable assertions.
244*/
245
246#ifdef SDL_WIKI_DOCUMENTATION_SECTION
247
248/**
249 * A macro for wrapping code in `do {} while (0);` without compiler warnings.
250 *
251 * Visual Studio with really aggressive warnings enabled needs this to avoid
252 * compiler complaints.
253 *
254 * the `do {} while (0);` trick is useful for wrapping code in a macro that
255 * may or may not be a single statement, to avoid various C language
256 * accidents.
257 *
258 * To use:
259 *
260 * ```c
261 * do { SomethingOnce(); } while (SDL_NULL_WHILE_LOOP_CONDITION (0));
262 * ```
263 *
264 * \since This macro is available since SDL 3.2.0.
265 */
266#define SDL_NULL_WHILE_LOOP_CONDITION (0)
267
268#elif defined(_MSC_VER) /* Avoid /W4 warnings. */
269/* "while (0,0)" fools Microsoft's compiler's /W4 warning level into thinking
270 this condition isn't constant. And looks like an owl's face! */
271#define SDL_NULL_WHILE_LOOP_CONDITION (0,0)
272#else
273#define SDL_NULL_WHILE_LOOP_CONDITION (0)
274#endif
275
276/**
277 * The macro used when an assertion is disabled.
278 *
279 * This isn't for direct use by apps, but this is the code that is inserted
280 * when an SDL_assert is disabled (perhaps in a release build).
281 *
282 * The code does nothing, but wraps `condition` in a sizeof operator, which
283 * generates no code and has no side effects, but avoid compiler warnings
284 * about unused variables.
285 *
286 * \param condition the condition to assert (but not actually run here).
287 *
288 * \since This macro is available since SDL 3.2.0.
289 */
290#define SDL_disabled_assert(condition) \
291 do { (void) sizeof ((condition)); } while (SDL_NULL_WHILE_LOOP_CONDITION)
292
293/**
294 * Possible outcomes from a triggered assertion.
295 *
296 * When an enabled assertion triggers, it may call the assertion handler
297 * (possibly one provided by the app via SDL_SetAssertionHandler), which will
298 * return one of these values, possibly after asking the user.
299 *
300 * Then SDL will respond based on this outcome (loop around to retry the
301 * condition, try to break in a debugger, kill the program, or ignore the
302 * problem).
303 *
304 * \since This enum is available since SDL 3.2.0.
305 */
306typedef enum SDL_AssertState
307{
308 SDL_ASSERTION_RETRY, /**< Retry the assert immediately. */
309 SDL_ASSERTION_BREAK, /**< Make the debugger trigger a breakpoint. */
310 SDL_ASSERTION_ABORT, /**< Terminate the program. */
311 SDL_ASSERTION_IGNORE, /**< Ignore the assert. */
312 SDL_ASSERTION_ALWAYS_IGNORE /**< Ignore the assert from now on. */
314
315/**
316 * Information about an assertion failure.
317 *
318 * This structure is filled in with information about a triggered assertion,
319 * used by the assertion handler, then added to the assertion report. This is
320 * returned as a linked list from SDL_GetAssertionReport().
321 *
322 * \since This struct is available since SDL 3.2.0.
323 */
324typedef struct SDL_AssertData
325{
326 bool always_ignore; /**< true if app should always continue when assertion is triggered. */
327 unsigned int trigger_count; /**< Number of times this assertion has been triggered. */
328 const char *condition; /**< A string of this assert's test code. */
329 const char *filename; /**< The source file where this assert lives. */
330 int linenum; /**< The line in `filename` where this assert lives. */
331 const char *function; /**< The name of the function where this assert lives. */
332 const struct SDL_AssertData *next; /**< next item in the linked list. */
334
335/**
336 * Never call this directly.
337 *
338 * Use the SDL_assert macros instead.
339 *
340 * \param data assert data structure.
341 * \param func function name.
342 * \param file file name.
343 * \param line line number.
344 * \returns assert state.
345 *
346 * \threadsafety It is safe to call this function from any thread.
347 *
348 * \since This function is available since SDL 3.2.0.
349 */
350extern SDL_DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *data,
351 const char *func,
352 const char *file, int line) SDL_ANALYZER_NORETURN;
353
354
355#ifdef SDL_WIKI_DOCUMENTATION_SECTION
356
357/**
358 * The macro used when an assertion triggers a breakpoint.
359 *
360 * This isn't for direct use by apps; use SDL_assert or SDL_TriggerBreakpoint
361 * instead.
362 *
363 * \since This macro is available since SDL 3.2.0.
364 */
365#define SDL_AssertBreakpoint() SDL_TriggerBreakpoint()
366
367#elif !defined(SDL_AssertBreakpoint)
368# if defined(ANDROID) && defined(assert)
369 /* Define this as empty in case assert() is defined as SDL_assert */
370# define SDL_AssertBreakpoint()
371# else
372# define SDL_AssertBreakpoint() SDL_TriggerBreakpoint()
373# endif
374#endif /* !SDL_AssertBreakpoint */
375
376/**
377 * The macro used when an assertion is enabled.
378 *
379 * This isn't for direct use by apps, but this is the code that is inserted
380 * when an SDL_assert is enabled.
381 *
382 * The `do {} while(0)` avoids dangling else problems:
383 *
384 * ```c
385 * if (x) SDL_assert(y); else blah();
386 * ```
387 *
388 * ... without the do/while, the "else" could attach to this macro's "if". We
389 * try to handle just the minimum we need here in a macro...the loop, the
390 * static vars, and break points. The heavy lifting is handled in
391 * SDL_ReportAssertion().
392 *
393 * \param condition the condition to assert.
394 *
395 * \since This macro is available since SDL 3.2.0.
396 */
397#define SDL_enabled_assert(condition) \
398 do { \
399 while ( !(condition) ) { \
400 static struct SDL_AssertData sdl_assert_data = { false, 0, #condition, NULL, 0, NULL, NULL }; \
401 const SDL_AssertState sdl_assert_state = SDL_ReportAssertion(&sdl_assert_data, SDL_FUNCTION, SDL_ASSERT_FILE, SDL_LINE); \
402 if (sdl_assert_state == SDL_ASSERTION_RETRY) { \
403 continue; /* go again. */ \
404 } else if (sdl_assert_state == SDL_ASSERTION_BREAK) { \
405 SDL_AssertBreakpoint(); \
406 } \
407 break; /* not retrying. */ \
408 } \
409 } while (SDL_NULL_WHILE_LOOP_CONDITION)
410
411#ifdef SDL_WIKI_DOCUMENTATION_SECTION
412
413/**
414 * An assertion test that is normally performed only in debug builds.
415 *
416 * This macro is enabled when the SDL_ASSERT_LEVEL is >= 2, otherwise it is
417 * disabled. This is meant to only do these tests in debug builds, so they can
418 * tend to be more expensive, and they are meant to bring everything to a halt
419 * when they fail, with the programmer there to assess the problem.
420 *
421 * In short: you can sprinkle these around liberally and assume they will
422 * evaporate out of the build when building for end-users.
423 *
424 * When assertions are disabled, this wraps `condition` in a `sizeof`
425 * operator, which means any function calls and side effects will not run, but
426 * the compiler will not complain about any otherwise-unused variables that
427 * are only referenced in the assertion.
428 *
429 * One can set the environment variable "SDL_ASSERT" to one of several strings
430 * ("abort", "break", "retry", "ignore", "always_ignore") to force a default
431 * behavior, which may be desirable for automation purposes. If your platform
432 * requires GUI interfaces to happen on the main thread but you're debugging
433 * an assertion in a background thread, it might be desirable to set this to
434 * "break" so that your debugger takes control as soon as assert is triggered,
435 * instead of risking a bad UI interaction (deadlock, etc) in the application.
436 *
437 * \param condition boolean value to test.
438 *
439 * \threadsafety It is safe to call this macro from any thread.
440 *
441 * \since This macro is available since SDL 3.2.0.
442 */
443#define SDL_assert(condition) if (assertion_enabled && (condition)) { trigger_assertion; }
444
445/**
446 * An assertion test that is performed even in release builds.
447 *
448 * This macro is enabled when the SDL_ASSERT_LEVEL is >= 1, otherwise it is
449 * disabled. This is meant to be for tests that are cheap to make and
450 * extremely unlikely to fail; generally it is frowned upon to have an
451 * assertion failure in a release build, so these assertions generally need to
452 * be of more than life-and-death importance if there's a chance they might
453 * trigger. You should almost always consider handling these cases more
454 * gracefully than an assert allows.
455 *
456 * When assertions are disabled, this wraps `condition` in a `sizeof`
457 * operator, which means any function calls and side effects will not run, but
458 * the compiler will not complain about any otherwise-unused variables that
459 * are only referenced in the assertion.
460 *
461 * One can set the environment variable "SDL_ASSERT" to one of several strings
462 * ("abort", "break", "retry", "ignore", "always_ignore") to force a default
463 * behavior, which may be desirable for automation purposes. If your platform
464 * requires GUI interfaces to happen on the main thread but you're debugging
465 * an assertion in a background thread, it might be desirable to set this to
466 * "break" so that your debugger takes control as soon as assert is triggered,
467 * instead of risking a bad UI interaction (deadlock, etc) in the application.
468 * *
469 *
470 * \param condition boolean value to test.
471 *
472 * \threadsafety It is safe to call this macro from any thread.
473 *
474 * \since This macro is available since SDL 3.2.0.
475 */
476#define SDL_assert_release(condition) SDL_disabled_assert(condition)
477
478/**
479 * An assertion test that is performed only when built with paranoid settings.
480 *
481 * This macro is enabled when the SDL_ASSERT_LEVEL is >= 3, otherwise it is
482 * disabled. This is a higher level than both release and debug, so these
483 * tests are meant to be expensive and only run when specifically looking for
484 * extremely unexpected failure cases in a special build.
485 *
486 * When assertions are disabled, this wraps `condition` in a `sizeof`
487 * operator, which means any function calls and side effects will not run, but
488 * the compiler will not complain about any otherwise-unused variables that
489 * are only referenced in the assertion.
490 *
491 * One can set the environment variable "SDL_ASSERT" to one of several strings
492 * ("abort", "break", "retry", "ignore", "always_ignore") to force a default
493 * behavior, which may be desirable for automation purposes. If your platform
494 * requires GUI interfaces to happen on the main thread but you're debugging
495 * an assertion in a background thread, it might be desirable to set this to
496 * "break" so that your debugger takes control as soon as assert is triggered,
497 * instead of risking a bad UI interaction (deadlock, etc) in the application.
498 *
499 * \param condition boolean value to test.
500 *
501 * \threadsafety It is safe to call this macro from any thread.
502 *
503 * \since This macro is available since SDL 3.2.0.
504 */
505#define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
506
507/* Enable various levels of assertions. */
508#elif SDL_ASSERT_LEVEL == 0 /* assertions disabled */
509# define SDL_assert(condition) SDL_disabled_assert(condition)
510# define SDL_assert_release(condition) SDL_disabled_assert(condition)
511# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
512#elif SDL_ASSERT_LEVEL == 1 /* release settings. */
513# define SDL_assert(condition) SDL_disabled_assert(condition)
514# define SDL_assert_release(condition) SDL_enabled_assert(condition)
515# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
516#elif SDL_ASSERT_LEVEL == 2 /* debug settings. */
517# define SDL_assert(condition) SDL_enabled_assert(condition)
518# define SDL_assert_release(condition) SDL_enabled_assert(condition)
519# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
520#elif SDL_ASSERT_LEVEL == 3 /* paranoid settings. */
521# define SDL_assert(condition) SDL_enabled_assert(condition)
522# define SDL_assert_release(condition) SDL_enabled_assert(condition)
523# define SDL_assert_paranoid(condition) SDL_enabled_assert(condition)
524#else
525# error Unknown assertion level.
526#endif
527
528/**
529 * An assertion test that is always performed.
530 *
531 * This macro is always enabled no matter what SDL_ASSERT_LEVEL is set to. You
532 * almost never want to use this, as it could trigger on an end-user's system,
533 * crashing your program.
534 *
535 * One can set the environment variable "SDL_ASSERT" to one of several strings
536 * ("abort", "break", "retry", "ignore", "always_ignore") to force a default
537 * behavior, which may be desirable for automation purposes. If your platform
538 * requires GUI interfaces to happen on the main thread but you're debugging
539 * an assertion in a background thread, it might be desirable to set this to
540 * "break" so that your debugger takes control as soon as assert is triggered,
541 * instead of risking a bad UI interaction (deadlock, etc) in the application.
542 *
543 * \param condition boolean value to test.
544 *
545 * \threadsafety It is safe to call this macro from any thread.
546 *
547 * \since This macro is available since SDL 3.2.0.
548 */
549#define SDL_assert_always(condition) SDL_enabled_assert(condition)
550
551
552/**
553 * A callback that fires when an SDL assertion fails.
554 *
555 * \param data a pointer to the SDL_AssertData structure corresponding to the
556 * current assertion.
557 * \param userdata what was passed as `userdata` to SDL_SetAssertionHandler().
558 * \returns an SDL_AssertState value indicating how to handle the failure.
559 *
560 * \threadsafety This callback may be called from any thread that triggers an
561 * assert at any time.
562 *
563 * \since This datatype is available since SDL 3.2.0.
564 */
566 const SDL_AssertData *data, void *userdata);
567
568/**
569 * Set an application-defined assertion handler.
570 *
571 * This function allows an application to show its own assertion UI and/or
572 * force the response to an assertion failure. If the application doesn't
573 * provide this, SDL will try to do the right thing, popping up a
574 * system-specific GUI dialog, and probably minimizing any fullscreen windows.
575 *
576 * This callback may fire from any thread, but it runs wrapped in a mutex, so
577 * it will only fire from one thread at a time.
578 *
579 * This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
580 *
581 * \param handler the SDL_AssertionHandler function to call when an assertion
582 * fails or NULL for the default handler.
583 * \param userdata a pointer that is passed to `handler`.
584 *
585 * \threadsafety It is safe to call this function from any thread.
586 *
587 * \since This function is available since SDL 3.2.0.
588 *
589 * \sa SDL_GetAssertionHandler
590 */
591extern SDL_DECLSPEC void SDLCALL SDL_SetAssertionHandler(
592 SDL_AssertionHandler handler,
593 void *userdata);
594
595/**
596 * Get the default assertion handler.
597 *
598 * This returns the function pointer that is called by default when an
599 * assertion is triggered. This is an internal function provided by SDL, that
600 * is used for assertions when SDL_SetAssertionHandler() hasn't been used to
601 * provide a different function.
602 *
603 * \returns the default SDL_AssertionHandler that is called when an assert
604 * triggers.
605 *
606 * \threadsafety It is safe to call this function from any thread.
607 *
608 * \since This function is available since SDL 3.2.0.
609 *
610 * \sa SDL_GetAssertionHandler
611 */
612extern SDL_DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetDefaultAssertionHandler(void);
613
614/**
615 * Get the current assertion handler.
616 *
617 * This returns the function pointer that is called when an assertion is
618 * triggered. This is either the value last passed to
619 * SDL_SetAssertionHandler(), or if no application-specified function is set,
620 * is equivalent to calling SDL_GetDefaultAssertionHandler().
621 *
622 * The parameter `puserdata` is a pointer to a void*, which will store the
623 * "userdata" pointer that was passed to SDL_SetAssertionHandler(). This value
624 * will always be NULL for the default handler. If you don't care about this
625 * data, it is safe to pass a NULL pointer to this function to ignore it.
626 *
627 * \param puserdata pointer which is filled with the "userdata" pointer that
628 * was passed to SDL_SetAssertionHandler().
629 * \returns the SDL_AssertionHandler that is called when an assert triggers.
630 *
631 * \threadsafety It is safe to call this function from any thread.
632 *
633 * \since This function is available since SDL 3.2.0.
634 *
635 * \sa SDL_SetAssertionHandler
636 */
637extern SDL_DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata);
638
639/**
640 * Get a list of all assertion failures.
641 *
642 * This function gets all assertions triggered since the last call to
643 * SDL_ResetAssertionReport(), or the start of the program.
644 *
645 * The proper way to examine this data looks something like this:
646 *
647 * ```c
648 * const SDL_AssertData *item = SDL_GetAssertionReport();
649 * while (item) {
650 * printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\\n",
651 * item->condition, item->function, item->filename,
652 * item->linenum, item->trigger_count,
653 * item->always_ignore ? "yes" : "no");
654 * item = item->next;
655 * }
656 * ```
657 *
658 * \returns a list of all failed assertions or NULL if the list is empty. This
659 * memory should not be modified or freed by the application. This
660 * pointer remains valid until the next call to SDL_Quit() or
661 * SDL_ResetAssertionReport().
662 *
663 * \threadsafety This function is not thread safe. Other threads calling
664 * SDL_ResetAssertionReport() simultaneously, may render the
665 * returned pointer invalid.
666 *
667 * \since This function is available since SDL 3.2.0.
668 *
669 * \sa SDL_ResetAssertionReport
670 */
671extern SDL_DECLSPEC const SDL_AssertData * SDLCALL SDL_GetAssertionReport(void);
672
673/**
674 * Clear the list of all assertion failures.
675 *
676 * This function will clear the list of all assertions triggered up to that
677 * point. Immediately following this call, SDL_GetAssertionReport will return
678 * no items. In addition, any previously-triggered assertions will be reset to
679 * a trigger_count of zero, and their always_ignore state will be false.
680 *
681 * \threadsafety This function is not thread safe. Other threads triggering an
682 * assertion, or simultaneously calling this function may cause
683 * memory leaks or crashes.
684 *
685 * \since This function is available since SDL 3.2.0.
686 *
687 * \sa SDL_GetAssertionReport
688 */
689extern SDL_DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
690
691/* Ends C function definitions when using C++ */
692#ifdef __cplusplus
693}
694#endif
695#include <SDL3/SDL_close_code.h>
696
697#endif /* SDL_assert_h_ */
SDL_AssertState
Definition SDL_assert.h:307
@ SDL_ASSERTION_RETRY
Definition SDL_assert.h:308
@ SDL_ASSERTION_ABORT
Definition SDL_assert.h:310
@ SDL_ASSERTION_IGNORE
Definition SDL_assert.h:311
@ SDL_ASSERTION_BREAK
Definition SDL_assert.h:309
@ SDL_ASSERTION_ALWAYS_IGNORE
Definition SDL_assert.h:312
SDL_AssertState(* SDL_AssertionHandler)(const SDL_AssertData *data, void *userdata)
Definition SDL_assert.h:565
SDL_AssertState SDL_ReportAssertion(SDL_AssertData *data, const char *func, const char *file, int line) SDL_ANALYZER_NORETURN
const SDL_AssertData * SDL_GetAssertionReport(void)
void SDL_ResetAssertionReport(void)
void SDL_SetAssertionHandler(SDL_AssertionHandler handler, void *userdata)
SDL_AssertionHandler SDL_GetDefaultAssertionHandler(void)
SDL_AssertionHandler SDL_GetAssertionHandler(void **puserdata)
#define SDL_ANALYZER_NORETURN
const struct SDL_AssertData * next
Definition SDL_assert.h:332
unsigned int trigger_count
Definition SDL_assert.h:327
const char * function
Definition SDL_assert.h:331
const char * filename
Definition SDL_assert.h:329
const char * condition
Definition SDL_assert.h:328