SDL 3.0
SDL_assert.h
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2023 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#ifndef SDL_assert_h_
23#define SDL_assert_h_
24
25#include <SDL3/SDL_stdinc.h>
26
27#include <SDL3/SDL_begin_code.h>
28/* Set up for C function definitions, even when using C++ */
29#ifdef __cplusplus
30extern "C" {
31#endif
32
33#ifndef SDL_ASSERT_LEVEL
34#ifdef SDL_DEFAULT_ASSERT_LEVEL
35#define SDL_ASSERT_LEVEL SDL_DEFAULT_ASSERT_LEVEL
36#elif defined(_DEBUG) || defined(DEBUG) || \
37 (defined(__GNUC__) && !defined(__OPTIMIZE__))
38#define SDL_ASSERT_LEVEL 2
39#else
40#define SDL_ASSERT_LEVEL 1
41#endif
42#endif /* SDL_ASSERT_LEVEL */
43
44/*
45These are macros and not first class functions so that the debugger breaks
46on the assertion line and not in some random guts of SDL, and so each
47assert can have unique static variables associated with it.
48*/
49
50#if defined(_MSC_VER)
51/* Don't include intrin.h here because it contains C++ code */
52 extern void __cdecl __debugbreak(void);
53 #define SDL_TriggerBreakpoint() __debugbreak()
54#elif defined(ANDROID)
55 #include <assert.h>
56 #define SDL_TriggerBreakpoint() assert(0)
57#elif SDL_HAS_BUILTIN(__builtin_debugtrap)
58 #define SDL_TriggerBreakpoint() __builtin_debugtrap()
59#elif (defined(__GNUC__) || defined(__clang__)) && (defined(__i386__) || defined(__x86_64__))
60 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
61#elif ( defined(__APPLE__) && (defined(__arm64__) || defined(__aarch64__)) ) /* this might work on other ARM targets, but this is a known quantity... */
62 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "brk #22\n\t" )
63#elif defined(__APPLE__) && defined(__arm__)
64 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "bkpt #22\n\t" )
65#elif defined(__386__) && defined(__WATCOMC__)
66 #define SDL_TriggerBreakpoint() { _asm { int 0x03 } }
67#elif defined(HAVE_SIGNAL_H) && !defined(__WATCOMC__)
68 #include <signal.h>
69 #define SDL_TriggerBreakpoint() raise(SIGTRAP)
70#else
71 /* How do we trigger breakpoints on this platform? */
72 #define SDL_TriggerBreakpoint()
73#endif
74
75#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
76# define SDL_FUNCTION __func__
77#elif ((defined(__GNUC__) && (__GNUC__ >= 2)) || defined(_MSC_VER) || defined (__WATCOMC__))
78# define SDL_FUNCTION __FUNCTION__
79#else
80# define SDL_FUNCTION "???"
81#endif
82#define SDL_FILE __FILE__
83#define SDL_LINE __LINE__
84
85/*
86sizeof (x) makes the compiler still parse the expression even without
87assertions enabled, so the code is always checked at compile time, but
88doesn't actually generate code for it, so there are no side effects or
89expensive checks at run time, just the constant size of what x WOULD be,
90which presumably gets optimized out as unused.
91This also solves the problem of...
92
93 int somevalue = blah();
94 SDL_assert(somevalue == 1);
95
96...which would cause compiles to complain that somevalue is unused if we
97disable assertions.
98*/
99
100/* "while (0,0)" fools Microsoft's compiler's /W4 warning level into thinking
101 this condition isn't constant. And looks like an owl's face! */
102#ifdef _MSC_VER /* stupid /W4 warnings. */
103#define SDL_NULL_WHILE_LOOP_CONDITION (0,0)
104#else
105#define SDL_NULL_WHILE_LOOP_CONDITION (0)
106#endif
107
108#define SDL_disabled_assert(condition) \
109 do { (void) sizeof ((condition)); } while (SDL_NULL_WHILE_LOOP_CONDITION)
110
111typedef enum
112{
113 SDL_ASSERTION_RETRY, /**< Retry the assert immediately. */
114 SDL_ASSERTION_BREAK, /**< Make the debugger trigger a breakpoint. */
115 SDL_ASSERTION_ABORT, /**< Terminate the program. */
116 SDL_ASSERTION_IGNORE, /**< Ignore the assert. */
117 SDL_ASSERTION_ALWAYS_IGNORE /**< Ignore the assert from now on. */
119
120typedef struct SDL_AssertData
121{
123 unsigned int trigger_count;
124 const char *condition;
125 const char *filename;
127 const char *function;
128 const struct SDL_AssertData *next;
130
131#if (SDL_ASSERT_LEVEL > 0)
132
133/* Never call this directly. Use the SDL_assert* macros. */
135 const char *,
136 const char *, int)
137#if defined(__clang__)
138#if __has_feature(attribute_analyzer_noreturn)
139/* this tells Clang's static analysis that we're a custom assert function,
140 and that the analyzer should assume the condition was always true past this
141 SDL_assert test. */
142 __attribute__((analyzer_noreturn))
143#endif
144#endif
145;
146
147/* the do {} while(0) avoids dangling else problems:
148 if (x) SDL_assert(y); else blah();
149 ... without the do/while, the "else" could attach to this macro's "if".
150 We try to handle just the minimum we need here in a macro...the loop,
151 the static vars, and break points. The heavy lifting is handled in
152 SDL_ReportAssertion(), in SDL_assert.c.
153*/
154#define SDL_enabled_assert(condition) \
155 do { \
156 while ( !(condition) ) { \
157 static struct SDL_AssertData sdl_assert_data = { \
158 0, 0, #condition, 0, 0, 0, 0 \
159 }; \
160 const SDL_AssertState sdl_assert_state = SDL_ReportAssertion(&sdl_assert_data, SDL_FUNCTION, SDL_FILE, SDL_LINE); \
161 if (sdl_assert_state == SDL_ASSERTION_RETRY) { \
162 continue; /* go again. */ \
163 } else if (sdl_assert_state == SDL_ASSERTION_BREAK) { \
164 SDL_TriggerBreakpoint(); \
165 } \
166 break; /* not retrying. */ \
167 } \
168 } while (SDL_NULL_WHILE_LOOP_CONDITION)
169
170#endif /* enabled assertions support code */
171
172/* Enable various levels of assertions. */
173#if SDL_ASSERT_LEVEL == 0 /* assertions disabled */
174# define SDL_assert(condition) SDL_disabled_assert(condition)
175# define SDL_assert_release(condition) SDL_disabled_assert(condition)
176# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
177#elif SDL_ASSERT_LEVEL == 1 /* release settings. */
178# define SDL_assert(condition) SDL_disabled_assert(condition)
179# define SDL_assert_release(condition) SDL_enabled_assert(condition)
180# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
181#elif SDL_ASSERT_LEVEL == 2 /* normal settings. */
182# define SDL_assert(condition) SDL_enabled_assert(condition)
183# define SDL_assert_release(condition) SDL_enabled_assert(condition)
184# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
185#elif SDL_ASSERT_LEVEL == 3 /* paranoid settings. */
186# define SDL_assert(condition) SDL_enabled_assert(condition)
187# define SDL_assert_release(condition) SDL_enabled_assert(condition)
188# define SDL_assert_paranoid(condition) SDL_enabled_assert(condition)
189#else
190# error Unknown assertion level.
191#endif
192
193/* this assertion is never disabled at any level. */
194#define SDL_assert_always(condition) SDL_enabled_assert(condition)
195
196
197/**
198 * A callback that fires when an SDL assertion fails.
199 *
200 * \param data a pointer to the SDL_AssertData structure corresponding to the
201 * current assertion
202 * \param userdata what was passed as `userdata` to SDL_SetAssertionHandler()
203 * \returns an SDL_AssertState value indicating how to handle the failure.
204 */
206 const SDL_AssertData* data, void* userdata);
207
208/**
209 * Set an application-defined assertion handler.
210 *
211 * This function allows an application to show its own assertion UI and/or
212 * force the response to an assertion failure. If the application doesn't
213 * provide this, SDL will try to do the right thing, popping up a
214 * system-specific GUI dialog, and probably minimizing any fullscreen windows.
215 *
216 * This callback may fire from any thread, but it runs wrapped in a mutex, so
217 * it will only fire from one thread at a time.
218 *
219 * This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
220 *
221 * \param handler the SDL_AssertionHandler function to call when an assertion
222 * fails or NULL for the default handler
223 * \param userdata a pointer that is passed to `handler`
224 *
225 * \since This function is available since SDL 3.0.0.
226 *
227 * \sa SDL_GetAssertionHandler
228 */
229extern DECLSPEC void SDLCALL SDL_SetAssertionHandler(
230 SDL_AssertionHandler handler,
231 void *userdata);
232
233/**
234 * Get the default assertion handler.
235 *
236 * This returns the function pointer that is called by default when an
237 * assertion is triggered. This is an internal function provided by SDL, that
238 * is used for assertions when SDL_SetAssertionHandler() hasn't been used to
239 * provide a different function.
240 *
241 * \returns the default SDL_AssertionHandler that is called when an assert
242 * triggers.
243 *
244 * \since This function is available since SDL 3.0.0.
245 *
246 * \sa SDL_GetAssertionHandler
247 */
249
250/**
251 * Get the current assertion handler.
252 *
253 * This returns the function pointer that is called when an assertion is
254 * triggered. This is either the value last passed to
255 * SDL_SetAssertionHandler(), or if no application-specified function is set,
256 * is equivalent to calling SDL_GetDefaultAssertionHandler().
257 *
258 * The parameter `puserdata` is a pointer to a void*, which will store the
259 * "userdata" pointer that was passed to SDL_SetAssertionHandler(). This value
260 * will always be NULL for the default handler. If you don't care about this
261 * data, it is safe to pass a NULL pointer to this function to ignore it.
262 *
263 * \param puserdata pointer which is filled with the "userdata" pointer that
264 * was passed to SDL_SetAssertionHandler()
265 * \returns the SDL_AssertionHandler that is called when an assert triggers.
266 *
267 * \since This function is available since SDL 3.0.0.
268 *
269 * \sa SDL_SetAssertionHandler
270 */
271extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata);
272
273/**
274 * Get a list of all assertion failures.
275 *
276 * This function gets all assertions triggered since the last call to
277 * SDL_ResetAssertionReport(), or the start of the program.
278 *
279 * The proper way to examine this data looks something like this:
280 *
281 * ```c
282 * const SDL_AssertData *item = SDL_GetAssertionReport();
283 * while (item) {
284 * printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\\n",
285 * item->condition, item->function, item->filename,
286 * item->linenum, item->trigger_count,
287 * item->always_ignore ? "yes" : "no");
288 * item = item->next;
289 * }
290 * ```
291 *
292 * \returns a list of all failed assertions or NULL if the list is empty. This
293 * memory should not be modified or freed by the application.
294 *
295 * \since This function is available since SDL 3.0.0.
296 *
297 * \sa SDL_ResetAssertionReport
298 */
299extern DECLSPEC const SDL_AssertData * SDLCALL SDL_GetAssertionReport(void);
300
301/**
302 * Clear the list of all assertion failures.
303 *
304 * This function will clear the list of all assertions triggered up to that
305 * point. Immediately following this call, SDL_GetAssertionReport will return
306 * no items. In addition, any previously-triggered assertions will be reset to
307 * a trigger_count of zero, and their always_ignore state will be false.
308 *
309 * \since This function is available since SDL 3.0.0.
310 *
311 * \sa SDL_GetAssertionReport
312 */
313extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
314
315/* Ends C function definitions when using C++ */
316#ifdef __cplusplus
317}
318#endif
319#include <SDL3/SDL_close_code.h>
320
321#endif /* SDL_assert_h_ */
SDL_AssertState
Definition: SDL_assert.h:112
@ SDL_ASSERTION_RETRY
Definition: SDL_assert.h:113
@ SDL_ASSERTION_ABORT
Definition: SDL_assert.h:115
@ SDL_ASSERTION_IGNORE
Definition: SDL_assert.h:116
@ SDL_ASSERTION_BREAK
Definition: SDL_assert.h:114
@ SDL_ASSERTION_ALWAYS_IGNORE
Definition: SDL_assert.h:117
SDL_AssertState(* SDL_AssertionHandler)(const SDL_AssertData *data, void *userdata)
Definition: SDL_assert.h:205
SDL_AssertState SDL_ReportAssertion(SDL_AssertData *, const char *, const char *, int)
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)
GLint GLenum GLsizei GLsizei GLsizei GLint GLsizei const GLvoid * data
Definition: SDL_opengl.h:1967
const struct SDL_AssertData * next
Definition: SDL_assert.h:128
unsigned int trigger_count
Definition: SDL_assert.h:123
const char * function
Definition: SDL_assert.h:127
const char * filename
Definition: SDL_assert.h:125
const char * condition
Definition: SDL_assert.h:124