2 Simple DirectMedia Layer
3 Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>
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.
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:
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.
25 #include "SDL_config.h"
27 #include "begin_code.h"
28 /* Set up for C function definitions, even when using C++ */
35 #ifndef SDL_ASSERT_LEVEL
36 #ifdef SDL_DEFAULT_ASSERT_LEVEL
37 #define SDL_ASSERT_LEVEL SDL_DEFAULT_ASSERT_LEVEL
38 #elif defined(_DEBUG) || defined(DEBUG) || \
39 (defined(__GNUC__) && !defined(__OPTIMIZE__))
40 #define SDL_ASSERT_LEVEL 2
42 #define SDL_ASSERT_LEVEL 1
44 #endif /* SDL_ASSERT_LEVEL */
47 These are macros and not first class functions so that the debugger breaks
48 on the assertion line and not in some random guts of SDL, and so each
49 assert can have unique static variables associated with it.
52 #if defined(_MSC_VER) && !defined(_WIN32_WCE)
53 /* Don't include intrin.h here because it contains C++ code */
54 extern void __cdecl __debugbreak(void);
55 #define SDL_TriggerBreakpoint() __debugbreak()
56 #elif (defined(__GNUC__) && ((__i386__) || (__x86_64__)))
57 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
58 #elif defined(HAVE_SIGNAL_H)
60 #define SDL_TriggerBreakpoint() raise(SIGTRAP)
62 /* How do we trigger breakpoints on this platform? */
63 #define SDL_TriggerBreakpoint()
66 #if (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
67 # define SDL_FUNCTION __func__
68 #elif ((__GNUC__ >= 2) || defined(_MSC_VER))
69 # define SDL_FUNCTION __FUNCTION__
71 # define SDL_FUNCTION "???"
73 #define SDL_FILE __FILE__
74 #define SDL_LINE __LINE__
77 sizeof (x) makes the compiler still parse the expression even without
78 assertions enabled, so the code is always checked at compile time, but
79 doesn't actually generate code for it, so there are no side effects or
80 expensive checks at run time, just the constant size of what x WOULD be,
81 which presumably gets optimized out as unused.
82 This also solves the problem of...
84 int somevalue = blah();
85 SDL_assert(somevalue == 1);
87 ...which would cause compiles to complain that somevalue is unused if we
91 #define SDL_disabled_assert(condition) \
92 do { (void) sizeof ((condition)); } while (0)
94 #if (SDL_ASSERT_LEVEL > 0)
98 SDL_ASSERTION_RETRY, /**< Retry the assert immediately. */
99 SDL_ASSERTION_BREAK, /**< Make the debugger trigger a breakpoint. */
100 SDL_ASSERTION_ABORT, /**< Terminate the program. */
101 SDL_ASSERTION_IGNORE, /**< Ignore the assert. */
102 SDL_ASSERTION_ALWAYS_IGNORE, /**< Ignore the assert from now on. */
105 typedef struct SDL_assert_data
108 unsigned int trigger_count;
109 const char *condition;
110 const char *filename;
112 const char *function;
113 const struct SDL_assert_data *next;
116 /* Never call this directly. Use the SDL_assert* macros. */
117 extern DECLSPEC SDL_assert_state SDLCALL SDL_ReportAssertion(SDL_assert_data *,
121 /* the do {} while(0) avoids dangling else problems:
122 if (x) SDL_assert(y); else blah();
123 ... without the do/while, the "else" could attach to this macro's "if".
124 We try to handle just the minimum we need here in a macro...the loop,
125 the static vars, and break points. The heavy lifting is handled in
126 SDL_ReportAssertion(), in SDL_assert.c.
128 #define SDL_enabled_assert(condition) \
130 while ( !(condition) ) { \
131 static struct SDL_assert_data assert_data = { \
132 0, 0, #condition, 0, 0, 0, 0 \
134 const SDL_assert_state state = SDL_ReportAssertion(&assert_data, \
138 if (state == SDL_ASSERTION_RETRY) { \
139 continue; /* go again. */ \
140 } else if (state == SDL_ASSERTION_BREAK) { \
141 SDL_TriggerBreakpoint(); \
143 break; /* not retrying. */ \
147 #endif /* enabled assertions support code */
149 /* Enable various levels of assertions. */
150 #if SDL_ASSERT_LEVEL == 0 /* assertions disabled */
151 # define SDL_assert(condition) SDL_disabled_assert(condition)
152 # define SDL_assert_release(condition) SDL_disabled_assert(condition)
153 # define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
154 #elif SDL_ASSERT_LEVEL == 1 /* release settings. */
155 # define SDL_assert(condition) SDL_disabled_assert(condition)
156 # define SDL_assert_release(condition) SDL_enabled_assert(condition)
157 # define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
158 #elif SDL_ASSERT_LEVEL == 2 /* normal settings. */
159 # define SDL_assert(condition) SDL_enabled_assert(condition)
160 # define SDL_assert_release(condition) SDL_enabled_assert(condition)
161 # define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
162 #elif SDL_ASSERT_LEVEL == 3 /* paranoid settings. */
163 # define SDL_assert(condition) SDL_enabled_assert(condition)
164 # define SDL_assert_release(condition) SDL_enabled_assert(condition)
165 # define SDL_assert_paranoid(condition) SDL_enabled_assert(condition)
167 # error Unknown assertion level.
171 typedef SDL_assert_state (SDLCALL *SDL_AssertionHandler)(
172 const SDL_assert_data* data, void* userdata);
175 * \brief Set an application-defined assertion handler.
177 * This allows an app to show its own assertion UI and/or force the
178 * response to an assertion failure. If the app doesn't provide this, SDL
179 * will try to do the right thing, popping up a system-specific GUI dialog,
180 * and probably minimizing any fullscreen windows.
182 * This callback may fire from any thread, but it runs wrapped in a mutex, so
183 * it will only fire from one thread at a time.
185 * Setting the callback to NULL restores SDL's original internal handler.
187 * This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
189 * \return SDL_assert_state value of how to handle the assertion failure.
191 * \param handler Callback function, called when an assertion fails.
192 * \param userdata A pointer passed to the callback as-is.
194 extern DECLSPEC void SDLCALL SDL_SetAssertionHandler(
195 SDL_AssertionHandler handler,
199 * \brief Get a list of all assertion failures.
201 * Get all assertions triggered since last call to SDL_ResetAssertionReport(),
202 * or the start of the program.
204 * The proper way to examine this data looks something like this:
207 * const SDL_assert_data *item = SDL_GetAssertionReport();
208 * while (item->condition) {
209 * printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\n",
210 * item->condition, item->function, item->filename,
211 * item->linenum, item->trigger_count,
212 * item->always_ignore ? "yes" : "no");
217 * \return List of all assertions. This never returns NULL,
218 * even if there are no items.
219 * \sa SDL_ResetAssertionReport
221 extern DECLSPEC const SDL_assert_data * SDLCALL SDL_GetAssertionReport(void);
224 * \brief Reset the list of all assertion failures.
226 * Reset list of all assertions triggered.
228 * \sa SDL_GetAssertionReport
230 extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
232 /* Ends C function definitions when using C++ */
238 #include "close_code.h"
240 #endif /* _SDL_assert_h */
242 /* vi: set ts=4 sw=4 expandtab: */