SDL standard library

Dependents:   H261_encoder

Revision:
0:dda4f4550403
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDL_assert.h	Wed Sep 07 18:46:53 2016 +0000
@@ -0,0 +1,284 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2014 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef _SDL_assert_h
+#define _SDL_assert_h
+
+#include "SDL_config.h"
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef SDL_ASSERT_LEVEL
+#ifdef SDL_DEFAULT_ASSERT_LEVEL
+#define SDL_ASSERT_LEVEL SDL_DEFAULT_ASSERT_LEVEL
+#elif defined(_DEBUG) || defined(DEBUG) || \
+      (defined(__GNUC__) && !defined(__OPTIMIZE__))
+#define SDL_ASSERT_LEVEL 2
+#else
+#define SDL_ASSERT_LEVEL 1
+#endif
+#endif /* SDL_ASSERT_LEVEL */
+
+/*
+These are macros and not first class functions so that the debugger breaks
+on the assertion line and not in some random guts of SDL, and so each
+assert can have unique static variables associated with it.
+*/
+
+#if defined(_MSC_VER)
+/* Don't include intrin.h here because it contains C++ code */
+    extern void __cdecl __debugbreak(void);
+    #define SDL_TriggerBreakpoint() __debugbreak()
+#elif (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)))
+    #define SDL_TriggerBreakpoint() __asm__ __volatile__ ( "int $3\n\t" )
+#elif defined(HAVE_SIGNAL_H)
+    #include <signal.h>
+    #define SDL_TriggerBreakpoint() raise(SIGTRAP)
+#else
+    /* How do we trigger breakpoints on this platform? */
+    #define SDL_TriggerBreakpoint()
+#endif
+
+#if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 supports __func__ as a standard. */
+#   define SDL_FUNCTION __func__
+#elif ((__GNUC__ >= 2) || defined(_MSC_VER))
+#   define SDL_FUNCTION __FUNCTION__
+#else
+#   define SDL_FUNCTION "???"
+#endif
+#define SDL_FILE    __FILE__
+#define SDL_LINE    __LINE__
+
+/*
+sizeof (x) makes the compiler still parse the expression even without
+assertions enabled, so the code is always checked at compile time, but
+doesn't actually generate code for it, so there are no side effects or
+expensive checks at run time, just the constant size of what x WOULD be,
+which presumably gets optimized out as unused.
+This also solves the problem of...
+
+    int somevalue = blah();
+    SDL_assert(somevalue == 1);
+
+...which would cause compiles to complain that somevalue is unused if we
+disable assertions.
+*/
+
+#ifdef _MSC_VER  /* stupid /W4 warnings. */
+#define SDL_NULL_WHILE_LOOP_CONDITION (-1 == __LINE__)
+#else
+#define SDL_NULL_WHILE_LOOP_CONDITION (0)
+#endif
+
+#define SDL_disabled_assert(condition) \
+    do { (void) sizeof ((condition)); } while (SDL_NULL_WHILE_LOOP_CONDITION)
+
+typedef enum
+{
+    SDL_ASSERTION_RETRY,  /**< Retry the assert immediately. */
+    SDL_ASSERTION_BREAK,  /**< Make the debugger trigger a breakpoint. */
+    SDL_ASSERTION_ABORT,  /**< Terminate the program. */
+    SDL_ASSERTION_IGNORE,  /**< Ignore the assert. */
+    SDL_ASSERTION_ALWAYS_IGNORE  /**< Ignore the assert from now on. */
+} SDL_assert_state;
+
+typedef struct SDL_assert_data
+{
+    int always_ignore;
+    unsigned int trigger_count;
+    const char *condition;
+    const char *filename;
+    int linenum;
+    const char *function;
+    const struct SDL_assert_data *next;
+} SDL_assert_data;
+
+#if (SDL_ASSERT_LEVEL > 0)
+
+/* Never call this directly. Use the SDL_assert* macros. */
+extern DECLSPEC SDL_assert_state SDLCALL SDL_ReportAssertion(SDL_assert_data *,
+                                                             const char *,
+                                                             const char *, int)
+#if defined(__clang__)
+#if __has_feature(attribute_analyzer_noreturn)
+/* this tells Clang's static analysis that we're a custom assert function,
+   and that the analyzer should assume the condition was always true past this
+   SDL_assert test. */
+   __attribute__((analyzer_noreturn))
+#endif
+#endif
+;
+
+/* the do {} while(0) avoids dangling else problems:
+    if (x) SDL_assert(y); else blah();
+       ... without the do/while, the "else" could attach to this macro's "if".
+   We try to handle just the minimum we need here in a macro...the loop,
+   the static vars, and break points. The heavy lifting is handled in
+   SDL_ReportAssertion(), in SDL_assert.c.
+*/
+#define SDL_enabled_assert(condition) \
+    do { \
+        while ( !(condition) ) { \
+            static struct SDL_assert_data assert_data = { \
+                0, 0, #condition, 0, 0, 0, 0 \
+            }; \
+            const SDL_assert_state state = SDL_ReportAssertion(&assert_data, \
+                                                               SDL_FUNCTION, \
+                                                               SDL_FILE, \
+                                                               SDL_LINE); \
+            if (state == SDL_ASSERTION_RETRY) { \
+                continue; /* go again. */ \
+            } else if (state == SDL_ASSERTION_BREAK) { \
+                SDL_TriggerBreakpoint(); \
+            } \
+            break; /* not retrying. */ \
+        } \
+    } while (SDL_NULL_WHILE_LOOP_CONDITION)
+
+#endif  /* enabled assertions support code */
+
+/* Enable various levels of assertions. */
+#if SDL_ASSERT_LEVEL == 0   /* assertions disabled */
+#   define SDL_assert(condition) SDL_disabled_assert(condition)
+#   define SDL_assert_release(condition) SDL_disabled_assert(condition)
+#   define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
+#elif SDL_ASSERT_LEVEL == 1  /* release settings. */
+#   define SDL_assert(condition) SDL_disabled_assert(condition)
+#   define SDL_assert_release(condition) SDL_enabled_assert(condition)
+#   define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
+#elif SDL_ASSERT_LEVEL == 2  /* normal settings. */
+#   define SDL_assert(condition) SDL_enabled_assert(condition)
+#   define SDL_assert_release(condition) SDL_enabled_assert(condition)
+#   define SDL_assert_paranoid(condition) SDL_disabled_assert(condition)
+#elif SDL_ASSERT_LEVEL == 3  /* paranoid settings. */
+#   define SDL_assert(condition) SDL_enabled_assert(condition)
+#   define SDL_assert_release(condition) SDL_enabled_assert(condition)
+#   define SDL_assert_paranoid(condition) SDL_enabled_assert(condition)
+#else
+#   error Unknown assertion level.
+#endif
+
+/* this assertion is never disabled at any level. */
+#define SDL_assert_always(condition) SDL_enabled_assert(condition)
+
+
+typedef SDL_assert_state (SDLCALL *SDL_AssertionHandler)(
+                                 const SDL_assert_data* data, void* userdata);
+
+/**
+ *  \brief Set an application-defined assertion handler.
+ *
+ *  This allows an app to show its own assertion UI and/or force the
+ *  response to an assertion failure. If the app doesn't provide this, SDL
+ *  will try to do the right thing, popping up a system-specific GUI dialog,
+ *  and probably minimizing any fullscreen windows.
+ *
+ *  This callback may fire from any thread, but it runs wrapped in a mutex, so
+ *  it will only fire from one thread at a time.
+ *
+ *  Setting the callback to NULL restores SDL's original internal handler.
+ *
+ *  This callback is NOT reset to SDL's internal handler upon SDL_Quit()!
+ *
+ *  \return SDL_assert_state value of how to handle the assertion failure.
+ *
+ *  \param handler Callback function, called when an assertion fails.
+ *  \param userdata A pointer passed to the callback as-is.
+ */
+extern DECLSPEC void SDLCALL SDL_SetAssertionHandler(
+                                            SDL_AssertionHandler handler,
+                                            void *userdata);
+
+/**
+ *  \brief Get the default assertion handler.
+ *
+ *  This returns the function pointer that is called by default when an
+ *   assertion is triggered. This is an internal function provided by SDL,
+ *   that is used for assertions when SDL_SetAssertionHandler() hasn't been
+ *   used to provide a different function.
+ *
+ *  \return The default SDL_AssertionHandler that is called when an assert triggers.
+ */
+extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetDefaultAssertionHandler(void);
+
+/**
+ *  \brief Get the current assertion handler.
+ *
+ *  This returns the function pointer that is called when an assertion is
+ *   triggered. This is either the value last passed to
+ *   SDL_SetAssertionHandler(), or if no application-specified function is
+ *   set, is equivalent to calling SDL_GetDefaultAssertionHandler().
+ *
+ *   \param puserdata Pointer to a void*, which will store the "userdata"
+ *                    pointer that was passed to SDL_SetAssertionHandler().
+ *                    This value will always be NULL for the default handler.
+ *                    If you don't care about this data, it is safe to pass
+ *                    a NULL pointer to this function to ignore it.
+ *  \return The SDL_AssertionHandler that is called when an assert triggers.
+ */
+extern DECLSPEC SDL_AssertionHandler SDLCALL SDL_GetAssertionHandler(void **puserdata);
+
+/**
+ *  \brief Get a list of all assertion failures.
+ *
+ *  Get all assertions triggered since last call to SDL_ResetAssertionReport(),
+ *  or the start of the program.
+ *
+ *  The proper way to examine this data looks something like this:
+ *
+ *  <code>
+ *  const SDL_assert_data *item = SDL_GetAssertionReport();
+ *  while (item) {
+ *      printf("'%s', %s (%s:%d), triggered %u times, always ignore: %s.\n",
+ *             item->condition, item->function, item->filename,
+ *             item->linenum, item->trigger_count,
+ *             item->always_ignore ? "yes" : "no");
+ *      item = item->next;
+ *  }
+ *  </code>
+ *
+ *  \return List of all assertions.
+ *  \sa SDL_ResetAssertionReport
+ */
+extern DECLSPEC const SDL_assert_data * SDLCALL SDL_GetAssertionReport(void);
+
+/**
+ *  \brief Reset the list of all assertion failures.
+ *
+ *  Reset list of all assertions triggered.
+ *
+ *  \sa SDL_GetAssertionReport
+ */
+extern DECLSPEC void SDLCALL SDL_ResetAssertionReport(void);
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include "close_code.h"
+
+#endif /* _SDL_assert_h */
+
+/* vi: set ts=4 sw=4 expandtab: */