SDL_assert.h (10577B)
1/* 2 Simple DirectMedia Layer 3 Copyright (C) 1997-2014 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(__i386__) || defined(__x86_64__))) 55 #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" ) 56#elif defined(HAVE_SIGNAL_H) 57 #include <signal.h> 58 #define SDL_TriggerBreakpoint() raise(SIGTRAP) 59#else 60 /* How do we trigger breakpoints on this platform? */ 61 #define SDL_TriggerBreakpoint() 62#endif 63 64#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */ 65# define SDL_FUNCTION __func__ 66#elif ((__GNUC__ >= 2) || defined(_MSC_VER)) 67# define SDL_FUNCTION __FUNCTION__ 68#else 69# define SDL_FUNCTION "???" 70#endif 71#define SDL_FILE __FILE__ 72#define SDL_LINE __LINE__ 73 74/* 75sizeof (x) makes the compiler still parse the expression even without 76assertions enabled, so the code is always checked at compile time, but 77doesn't actually generate code for it, so there are no side effects or 78expensive checks at run time, just the constant size of what x WOULD be, 79which presumably gets optimized out as unused. 80This also solves the problem of... 81 82 int somevalue = blah(); 83 SDL_assert(somevalue == 1); 84 85...which would cause compiles to complain that somevalue is unused if we 86disable assertions. 87*/ 88 89#ifdef _MSC_VER /* stupid /W4 warnings. */ 90#define SDL_NULL_WHILE_LOOP_CONDITION (-1 == __LINE__) 91#else 92#define SDL_NULL_WHILE_LOOP_CONDITION (0) 93#endif 94 95#define SDL_disabled_assert(condition) \ 96 do { (void) sizeof ((condition)); } while (SDL_NULL_WHILE_LOOP_CONDITION) 97 98typedef enum 99{ 100 SDL_ASSERTION_RETRY, /**< Retry the assert immediately. */ 101 SDL_ASSERTION_BREAK, /**< Make the debugger trigger a breakpoint. */ 102 SDL_ASSERTION_ABORT, /**< Terminate the program. */ 103 SDL_ASSERTION_IGNORE, /**< Ignore the assert. */ 104 SDL_ASSERTION_ALWAYS_IGNORE /**< Ignore the assert from now on. */ 105} SDL_assert_state; 106 107typedef struct SDL_assert_data 108{ 109 int always_ignore; 110 unsigned int trigger_count; 111 const char *condition; 112 const char *filename; 113 int linenum; 114 const char *function; 115 const struct SDL_assert_data *next; 116} SDL_assert_data; 117 118#if (SDL_ASSERT_LEVEL > 0) 119 120/* Never call this directly. Use the SDL_assert* macros. */ 121extern DECLSPEC SDL_assert_state SDLCALL SDL_ReportAssertion(SDL_assert_data *, 122 const char *, 123 const char *, int) 124#if defined(__clang__) 125#if __has_feature(attribute_analyzer_noreturn) 126/* this tells Clang's static analysis that we're a custom assert function, 127 and that the analyzer should assume the condition was always true past this 128 SDL_assert test. */ 129 __attribute__((analyzer_noreturn)) 130#endif 131#endif 132; 133 134/* the do {} while(0) avoids dangling else problems: 135 if (x) SDL_assert(y); else blah(); 136 ... without the do/while, the "else" could attach to this macro's "if". 137 We try to handle just the minimum we need here in a macro...the loop, 138 the static vars, and break points. The heavy lifting is handled in 139 SDL_ReportAssertion(), in SDL_assert.c. 140*/ 141#define SDL_enabled_assert(condition) \ 142 do { \ 143 while ( !(condition) ) { \ 144 static struct SDL_assert_data sdl_assert_data = { \ 145 0, 0, #condition, 0, 0, 0, 0 \ 146 }; \ 147 const SDL_assert_state sdl_assert_state = SDL_ReportAssertion(&sdl_assert_data, SDL_FUNCTION, SDL_FILE, SDL_LINE); \ 148 if (sdl_assert_state == SDL_ASSERTION_RETRY) { \ 149 continue; /* go again. */ \ 150 } else if (sdl_assert_state == SDL_ASSERTION_BREAK) { \ 151 SDL_TriggerBreakpoint(); \ 152 } \ 153 break; /* not retrying. */ \ 154 } \ 155 } while (SDL_NULL_WHILE_LOOP_CONDITION) 156 157#endif /* enabled assertions support code */ 158 159/* Enable various levels of assertions. */ 160#if SDL_ASSERT_LEVEL == 0 /* assertions disabled */ 161# define SDL_assert(condition) SDL_disabled_assert(condition) 162# define SDL_assert_release(condition) SDL_disabled_assert(condition) 163# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition) 164#elif SDL_ASSERT_LEVEL == 1 /* release settings. */ 165# define SDL_assert(condition) SDL_disabled_assert(condition) 166# define SDL_assert_release(condition) SDL_enabled_assert(condition) 167# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition) 168#elif SDL_ASSERT_LEVEL == 2 /* normal settings. */ 169# define SDL_assert(condition) SDL_enabled_assert(condition) 170# define SDL_assert_release(condition) SDL_enabled_assert(condition) 171# define SDL_assert_paranoid(condition) SDL_disabled_assert(condition) 172#elif SDL_ASSERT_LEVEL == 3 /* paranoid settings. */ 173# define SDL_assert(condition) SDL_enabled_assert(condition) 174# define SDL_assert_release(condition) SDL_enabled_assert(condition) 175# define SDL_assert_paranoid(condition) SDL_enabled_assert(condition) 176#else 177# error Unknown assertion level. 178#endif 179 180/* this assertion is never disabled at any level. */ 181#define SDL_assert_always(condition) SDL_enabled_assert(condition) 182 183 184typedef SDL_assert_state (SDLCALL *SDL_AssertionHandler)( 185 const SDL_assert_data* data, void* userdata); 186 187/** 188 * \brief Set an application-defined assertion handler. 189 * 190 * This allows an app to show its own assertion UI and/or force the 191 * response to an assertion failure. If the app doesn't provide this, SDL 192 * will try to do the right thing, popping up a system-specific GUI dialog, 193 * and probably minimizing any fullscreen windows. 194 * 195 * This callback may fire from any thread, but it runs wrapped in a mutex, so 196 * it will only fire from one thread at a time. 197 * 198 * Setting the callback to NULL restores SDL's original internal handler. 199 * 200 * This callback is NOT reset to SDL's internal handler upon SDL_Quit()! 201 * 202 * \return SDL_assert_state value of how to handle the assertion failure. 203 * 204 * \param handler Callback function, called when an assertion fails. 205 * \param userdata A pointer passed to the callback as-is. 206 */ 207extern DECLSPEC void SDLCALL SDL_SetAssertionHandler( 208 SDL_AssertionHandler handler, 209 void *userdata); 210 211/** 212 * \brief Get the default assertion handler. 213 * 214 * This returns the function pointer that is called by default when an 215 * assertion is triggered. This is an internal function provided by SDL, 216 * that is used for assertions when SDL_SetAssertionHandler() hasn't been 217 * used to provide a different function. 218 * 219 * \return The default SDL_AssertionHandler that is called when an assert triggers. 220 */ 221extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetDefaultAssertionHandler(void); 222 223/** 224 * \brief Get the current assertion handler. 225 * 226 * This returns the function pointer that is called when an assertion is 227 * triggered. This is either the value last passed to 228 * SDL_SetAssertionHandler(), or if no application-specified function is 229 * set, is equivalent to calling SDL_GetDefaultAssertionHandler(). 230 * 231 * \param puserdata Pointer to a void*, which will store the "userdata" 232 * pointer that was passed to SDL_SetAssertionHandler(). 233 * This value will always be NULL for the default handler. 234 * If you don't care about this data, it is safe to pass 235 * a NULL pointer to this function to ignore it. 236 * \return The SDL_AssertionHandler that is called when an assert triggers. 237 */ 238extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata); 239 240/** 241 * \brief Get a list of all assertion failures. 242 * 243 * Get all assertions triggered since last call to SDL_ResetAssertionReport(), 244 * or the start of the program. 245 * 246 * The proper way to examine this data looks something like this: 247 * 248 * <code> 249 * const SDL_assert_data *item = SDL_GetAssertionReport(); 250 * while (item) { 251 * printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\n", 252 * item->condition, item->function, item->filename, 253 * item->linenum, item->trigger_count, 254 * item->always_ignore ? "yes" : "no"); 255 * item = item->next; 256 * } 257 * </code> 258 * 259 * \return List of all assertions. 260 * \sa SDL_ResetAssertionReport 261 */ 262extern DECLSPEC const SDL_assert_data * SDLCALL SDL_GetAssertionReport(void); 263 264/** 265 * \brief Reset the list of all assertion failures. 266 * 267 * Reset list of all assertions triggered. 268 * 269 * \sa SDL_GetAssertionReport 270 */ 271extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void); 272 273/* Ends C function definitions when using C++ */ 274#ifdef __cplusplus 275} 276#endif 277#include "close_code.h" 278 279#endif /* _SDL_assert_h */ 280 281/* vi: set ts=4 sw=4 expandtab: */