1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2022 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 "SDL_config.h"
26
27#include "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(__NACL__)) && ((defined(__GNUC__) || defined(__clang__)) && (defined(__i386__) || defined(__x86_64__))) )
55 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
56#elif ( defined(__APPLE__) && (defined(__arm64__) || defined(__aarch64__)) ) /* this might work on other ARM targets, but this is a known quantity... */
57 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "brk #22\n\t" )
58#elif defined(__APPLE__) && defined(__arm__)
59 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "bkpt #22\n\t" )
60#elif defined(__386__) && defined(__WATCOMC__)
61 #define SDL_TriggerBreakpoint() { _asm { int 0x03 } }
62#elif defined(HAVE_SIGNAL_H) && !defined(__WATCOMC__)
63 #include <signal.h>
64 #define SDL_TriggerBreakpoint() raise(SIGTRAP)
65#else
66 /* How do we trigger breakpoints on this platform? */
67 #define SDL_TriggerBreakpoint()
68#endif
69
70#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
71# define SDL_FUNCTION __func__
72#elif ((__GNUC__ >= 2) || defined(_MSC_VER) || defined (__WATCOMC__))
73# define SDL_FUNCTION __FUNCTION__
74#else
75# define SDL_FUNCTION "???"
76#endif
77#define SDL_FILE __FILE__
78#define SDL_LINE __LINE__
79
80/*
81sizeof (x) makes the compiler still parse the expression even without
82assertions enabled, so the code is always checked at compile time, but
83doesn't actually generate code for it, so there are no side effects or
84expensive checks at run time, just the constant size of what x WOULD be,
85which presumably gets optimized out as unused.
86This also solves the problem of...
87
88 int somevalue = blah();
89 SDL_assert(somevalue == 1);
90
91...which would cause compiles to complain that somevalue is unused if we
92disable assertions.
93*/
94
95/* "while (0,0)" fools Microsoft's compiler's /W4 warning level into thinking
96 this condition isn't constant. And looks like an owl's face! */
97#ifdef _MSC_VER /* stupid /W4 warnings. */
98#define SDL_NULL_WHILE_LOOP_CONDITION (0,0)
99#else
100#define SDL_NULL_WHILE_LOOP_CONDITION (0)
101#endif
102
103#define SDL_disabled_assert(condition) \
104 do { (void) sizeof ((condition)); } while (SDL_NULL_WHILE_LOOP_CONDITION)
105
106typedef enum
107{
108 SDL_ASSERTION_RETRY, /**< Retry the assert immediately. */
109 SDL_ASSERTION_BREAK, /**< Make the debugger trigger a breakpoint. */
110 SDL_ASSERTION_ABORT, /**< Terminate the program. */
111 SDL_ASSERTION_IGNORE, /**< Ignore the assert. */
112 SDL_ASSERTION_ALWAYS_IGNORE /**< Ignore the assert from now on. */
113} SDL_AssertState;
114
115typedef struct SDL_AssertData
116{
117 int always_ignore;
118 unsigned int trigger_count;
119 const char *condition;
120 const char *filename;
121 int linenum;
122 const char *function;
123 const struct SDL_AssertData *next;
124} SDL_AssertData;
125
126#if (SDL_ASSERT_LEVEL > 0)
127
128/* Never call this directly. Use the SDL_assert* macros. */
129extern DECLSPEC SDL_AssertState SDLCALL SDL_ReportAssertion(SDL_AssertData *,
130 const char *,
131 const char *, int)
132#if defined(__clang__)
133#if __has_feature(attribute_analyzer_noreturn)
134/* this tells Clang's static analysis that we're a custom assert function,
135 and that the analyzer should assume the condition was always true past this
136 SDL_assert test. */
137 __attribute__((analyzer_noreturn))
138#endif
139#endif
140;
141
142/* the do {} while(0) avoids dangling else problems:
143 if (x) SDL_assert(y); else blah();
144 ... without the do/while, the "else" could attach to this macro's "if".
145 We try to handle just the minimum we need here in a macro...the loop,
146 the static vars, and break points. The heavy lifting is handled in
147 SDL_ReportAssertion(), in SDL_assert.c.
148*/
149#define SDL_enabled_assert(condition) \
150 do { \
151 while ( !(condition) ) { \
152 static struct SDL_AssertData sdl_assert_data = { \
153 0, 0, #condition, 0, 0, 0, 0 \
154 }; \
155 const SDL_AssertState sdl_assert_state = SDL_ReportAssertion(&sdl_assert_data, SDL_FUNCTION, SDL_FILE, SDL_LINE); \
156 if (sdl_assert_state == SDL_ASSERTION_RETRY) { \
157 continue; /* go again. */ \
158 } else if (sdl_assert_state == SDL_ASSERTION_BREAK) { \
159 SDL_TriggerBreakpoint(); \
160 } \
161 break; /* not retrying. */ \
162 } \
163 } while (SDL_NULL_WHILE_LOOP_CONDITION)
164
165#endif /* enabled assertions support code */
166
167/* Enable various levels of assertions. */
168#if SDL_ASSERT_LEVEL == 0 /* assertions disabled */
169# define SDL_assert(condition) SDL_disabled_assert(condition)
170# define SDL_assert_release(condition) SDL_disabled_assert(condition)
171# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
172#elif SDL_ASSERT_LEVEL == 1 /* release settings. */
173# define SDL_assert(condition) SDL_disabled_assert(condition)
174# define SDL_assert_release(condition) SDL_enabled_assert(condition)
175# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
176#elif SDL_ASSERT_LEVEL == 2 /* normal settings. */
177# define SDL_assert(condition) SDL_enabled_assert(condition)
178# define SDL_assert_release(condition) SDL_enabled_assert(condition)
179# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
180#elif SDL_ASSERT_LEVEL == 3 /* paranoid settings. */
181# define SDL_assert(condition) SDL_enabled_assert(condition)
182# define SDL_assert_release(condition) SDL_enabled_assert(condition)
183# define SDL_assert_paranoid(condition) SDL_enabled_assert(condition)
184#else
185# error Unknown assertion level.
186#endif
187
188/* this assertion is never disabled at any level. */
189#define SDL_assert_always(condition) SDL_enabled_assert(condition)
190
191
192/**
193 * A callback that fires when an SDL assertion fails.
194 *
195 * \param data a pointer to the SDL_AssertData structure corresponding to the
196 * current assertion
197 * \param userdata what was passed as `userdata` to SDL_SetAssertionHandler()
198 * \returns an SDL_AssertState value indicating how to handle the failure.
199 */
200typedef SDL_AssertState (SDLCALL *SDL_AssertionHandler)(
201 const SDL_AssertData* data, void* userdata);
202
203/**
204 * Set an application-defined assertion handler.
205 *
206 * This function allows an application to show its own assertion UI and/or
207 * force the response to an assertion failure. If the application doesn't
208 * provide this, SDL will try to do the right thing, popping up a
209 * system-specific GUI dialog, and probably minimizing any fullscreen windows.
210 *
211 * This callback may fire from any thread, but it runs wrapped in a mutex, so
212 * it will only fire from one thread at a time.
213 *
214 * This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
215 *
216 * \param handler the SDL_AssertionHandler function to call when an assertion
217 * fails or NULL for the default handler
218 * \param userdata a pointer that is passed to `handler`
219 *
220 * \since This function is available since SDL 2.0.0.
221 *
222 * \sa SDL_GetAssertionHandler
223 */
224extern DECLSPEC void SDLCALL SDL_SetAssertionHandler(
225 SDL_AssertionHandler handler,
226 void *userdata);
227
228/**
229 * Get the default assertion handler.
230 *
231 * This returns the function pointer that is called by default when an
232 * assertion is triggered. This is an internal function provided by SDL, that
233 * is used for assertions when SDL_SetAssertionHandler() hasn't been used to
234 * provide a different function.
235 *
236 * \returns the default SDL_AssertionHandler that is called when an assert
237 * triggers.
238 *
239 * \since This function is available since SDL 2.0.2.
240 *
241 * \sa SDL_GetAssertionHandler
242 */
243extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetDefaultAssertionHandler(void);
244
245/**
246 * Get the current assertion handler.
247 *
248 * This returns the function pointer that is called when an assertion is
249 * triggered. This is either the value last passed to
250 * SDL_SetAssertionHandler(), or if no application-specified function is set,
251 * is equivalent to calling SDL_GetDefaultAssertionHandler().
252 *
253 * The parameter `puserdata` is a pointer to a void*, which will store the
254 * "userdata" pointer that was passed to SDL_SetAssertionHandler(). This value
255 * will always be NULL for the default handler. If you don't care about this
256 * data, it is safe to pass a NULL pointer to this function to ignore it.
257 *
258 * \param puserdata pointer which is filled with the "userdata" pointer that
259 * was passed to SDL_SetAssertionHandler()
260 * \returns the SDL_AssertionHandler that is called when an assert triggers.
261 *
262 * \since This function is available since SDL 2.0.2.
263 *
264 * \sa SDL_SetAssertionHandler
265 */
266extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata);
267
268/**
269 * Get a list of all assertion failures.
270 *
271 * This function gets all assertions triggered since the last call to
272 * SDL_ResetAssertionReport(), or the start of the program.
273 *
274 * The proper way to examine this data looks something like this:
275 *
276 * ```c
277 * const SDL_AssertData *item = SDL_GetAssertionReport();
278 * while (item) {
279 * printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\\n",
280 * item->condition, item->function, item->filename,
281 * item->linenum, item->trigger_count,
282 * item->always_ignore ? "yes" : "no");
283 * item = item->next;
284 * }
285 * ```
286 *
287 * \returns a list of all failed assertions or NULL if the list is empty. This
288 * memory should not be modified or freed by the application.
289 *
290 * \since This function is available since SDL 2.0.0.
291 *
292 * \sa SDL_ResetAssertionReport
293 */
294extern DECLSPEC const SDL_AssertData * SDLCALL SDL_GetAssertionReport(void);
295
296/**
297 * Clear the list of all assertion failures.
298 *
299 * This function will clear the list of all assertions triggered up to that
300 * point. Immediately following this call, SDL_GetAssertionReport will return
301 * no items. In addition, any previously-triggered assertions will be reset to
302 * a trigger_count of zero, and their always_ignore state will be false.
303 *
304 * \since This function is available since SDL 2.0.0.
305 *
306 * \sa SDL_GetAssertionReport
307 */
308extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
309
310
311/* these had wrong naming conventions until 2.0.4. Please update your app! */
312#define SDL_assert_state SDL_AssertState
313#define SDL_assert_data SDL_AssertData
314
315
316/* Ends C function definitions when using C++ */
317#ifdef __cplusplus
318}
319#endif
320#include "close_code.h"
321
322#endif /* SDL_assert_h_ */
323
324/* vi: set ts=4 sw=4 expandtab: */
325