// Name: wx/debug.h
// Purpose: Misc debug functions and macros
// Author: Vadim Zeitlin
-// Modified by:
// Created: 29/01/98
// RCS-ID: $Id$
-// Copyright: (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
-// Licence: wxWindows license
+// Copyright: (c) 1998-2009 Vadim Zeitlin <vadim@wxwidgets.org>
+// Licence: wxWindows licence
/////////////////////////////////////////////////////////////////////////////
-#ifndef _WX_DEBUG_H_
-#define _WX_DEBUG_H_
+#ifndef _WX_DEBUG_H_
+#define _WX_DEBUG_H_
-#include <assert.h>
+#if !defined(__WXPALMOS5__) && !defined(__WXWINCE__)
+ #include <assert.h>
+#endif // systems without assert.h
-#include "wx/wxchar.h"
+#include <limits.h> // for CHAR_BIT used below
+
+#include "wx/chartype.h" // for __TFILE__ and wxChar
+#include "wx/cpp.h" // for __WXFUNCTION__
+
+class WXDLLIMPEXP_FWD_BASE wxString;
+class WXDLLIMPEXP_FWD_BASE wxCStrData;
// ----------------------------------------------------------------------------
// Defines controlling the debugging macros
// ----------------------------------------------------------------------------
+/*
+ wxWidgets can be built with several different levels of debug support
+ specified by the value of wxDEBUG_LEVEL constant:
+
+ 0: No assertion macros at all, this should only be used when optimizing
+ for resource-constrained systems (typically embedded ones).
+ 1: Default level, most of the assertions are enabled.
+ 2: Maximal (at least for now): asserts which are "expensive"
+ (performance-wise) or only make sense for finding errors in wxWidgets
+ itself, as opposed to bugs in applications using it, are also enabled.
+
+ For compatibility reasons, currently wxDEBUG_LEVEL is defined if
+ __WXDEBUG__ is defined but in the near future (2.9.1) the role of the flags
+ will change and wxDEBUG_LEVEL will be the primary value with __WXDEBUG__
+ only used for compatibility.
+ */
+
// if _DEBUG is defined (MS VC++ and others use it in debug builds), define
// __WXDEBUG__ too
#ifdef _DEBUG
#endif // !WXDEBUG
#endif // __WXDEBUG__
+// temporarily define wxDEBUG_LEVEL as function of __WXDEBUG__
+#if !defined(wxDEBUG_LEVEL)
+ #ifdef __WXDEBUG__
+ #define wxDEBUG_LEVEL 1
+ #else
+ #define wxDEBUG_LEVEL 0
+ #endif
+#endif // !defined(wxDEBUG_LEVEL)
+
// ----------------------------------------------------------------------------
-// Debugging macros
-//
-// All debugging macros rely on ASSERT() which in turn calls user-defined
-// OnAssert() function. To keep things simple, it's called even when the
-// expression is TRUE (i.e. everything is ok) and by default does nothing: just
-// returns the same value back. But if you redefine it to do something more sexy
-// (popping up a message box in your favourite GUI, sending you e-mail or
-// whatever) it will affect all ASSERTs, FAILs and CHECKs in your code.
+// Handling assertion failures
+// ----------------------------------------------------------------------------
+
+/*
+ Type for the function called in case of assert failure, see
+ wxSetAssertHandler().
+ */
+typedef void (*wxAssertHandler_t)(const wxString& file,
+ int line,
+ const wxString& func,
+ const wxString& cond,
+ const wxString& msg);
+
+#if wxDEBUG_LEVEL
+
+// the global assert handler function, if it is NULL asserts don't check their
+// conditions
+extern WXDLLIMPEXP_DATA_BASE(wxAssertHandler_t) wxTheAssertHandler;
+
+/*
+ Sets the function to be called in case of assertion failure.
+
+ The default assert handler forwards to wxApp::OnAssertFailure() whose
+ default behaviour is, in turn, to show the standard assertion failure
+ dialog if a wxApp object exists or shows the same dialog itself directly
+ otherwise.
+
+ While usually it is enough -- and more convenient -- to just override
+ OnAssertFailure(), to handle all assertion failures, including those
+ occurring even before wxApp object creation or after its destruction you
+ need to provide your assertion handler function.
+
+ This function also provides a simple way to disable all asserts: simply
+ pass NULL pointer to it. Doing this will result in not even evaluating
+ assert conditions at all, avoiding almost all run-time cost of asserts.
+
+ Notice that this function is not MT-safe, so you should call it before
+ starting any other threads.
+
+ The return value of this function is the previous assertion handler. It can
+ be called after any pre-processing by your handler and can also be restored
+ later if you uninstall your handler.
+ */
+inline wxAssertHandler_t wxSetAssertHandler(wxAssertHandler_t handler)
+{
+ const wxAssertHandler_t old = wxTheAssertHandler;
+ wxTheAssertHandler = handler;
+ return old;
+}
+
+#else // !wxDEBUG_LEVEL
+
+// provide empty stubs in case assertions are completely disabled
//
-// Warning: if you don't like advices on programming style, don't read
-// further! ;-)
+// NB: can't use WXUNUSED() here as we're included from wx/defs.h before it is
+// defined
+inline wxAssertHandler_t wxSetAssertHandler(wxAssertHandler_t /* handler */)
+{
+ return NULL;
+}
+
+#endif // wxDEBUG_LEVEL/!wxDEBUG_LEVEL
+
+// simply a synonym for wxSetAssertHandler(NULL)
+inline void wxDisableAsserts() { wxSetAssertHandler(NULL); }
+
+#if wxDEBUG_LEVEL
+
+/*
+ wxOnAssert() is used by the debugging macros defined below. Different
+ overloads are needed because these macros can be used with or without _T().
+
+ All of them are implemented in src/common/appcmn.cpp and unconditionally
+ call wxTheAssertHandler so the caller must check that it is non-NULL
+ (assert macros do it).
+ */
+
+#if wxUSE_UNICODE
+
+// these overloads are the ones typically used by debugging macros: we have to
+// provide wxChar* msg version because it's common to use _T() in the macros
+// and finally, we can't use const wx(char)* msg = NULL, because that would
+// be ambiguous
//
-// Extensive use of these macros is recommended! Remember that ASSERTs are
-// disabled in final (without __WXDEBUG__ defined) build, so they add strictly
-// nothing to your program's code. On the other hand, CHECK macros do stay
-// even in release builds, but in general are not much of a burden, while
-// a judicious use of them might increase your program's stability.
+// also notice that these functions can't be inline as wxString is not defined
+// yet (and can't be as wxString code itself may use assertions)
+extern void WXDLLIMPEXP_BASE wxOnAssert(const char *file,
+ int line,
+ const char *func,
+ const char *cond);
+
+extern void WXDLLIMPEXP_BASE wxOnAssert(const char *file,
+ int line,
+ const char *func,
+ const char *cond,
+ const char *msg);
+
+extern void WXDLLIMPEXP_BASE wxOnAssert(const char *file,
+ int line,
+ const char *func,
+ const char *cond,
+ const wxChar *msg);
+#endif /* wxUSE_UNICODE */
+
+// this version is for compatibility with wx 2.8 Unicode build only, we don't
+// use it ourselves any more except in ANSI-only build in which case it is all
+// we need
+extern void WXDLLIMPEXP_BASE wxOnAssert(const wxChar *file,
+ int line,
+ const char *func,
+ const wxChar *cond,
+ const wxChar *msg = NULL);
+
+// these overloads work when msg passed to debug macro is a string and we
+// also have to provide wxCStrData overload to resolve ambiguity which would
+// otherwise arise from wxASSERT( s.c_str() )
+extern void WXDLLIMPEXP_BASE wxOnAssert(const wxString& file,
+ int line,
+ const wxString& func,
+ const wxString& cond,
+ const wxString& msg);
+
+extern void WXDLLIMPEXP_BASE wxOnAssert(const wxString& file,
+ int line,
+ const wxString& func,
+ const wxString& cond);
+
+extern void WXDLLIMPEXP_BASE wxOnAssert(const char *file,
+ int line,
+ const char *func,
+ const char *cond,
+ const wxCStrData& msg);
+
+extern void WXDLLIMPEXP_BASE wxOnAssert(const char *file,
+ int line,
+ const char *func,
+ const char *cond,
+ const wxString& msg);
+
+#endif // wxDEBUG_LEVEL
+
+
+// ----------------------------------------------------------------------------
+// Debugging macros
// ----------------------------------------------------------------------------
-// Macros which are completely disabled in 'release' mode
-//
-// NB: these functions are implemented in src/common/appcmn.cpp
-#ifdef __WXDEBUG__
- /*
- this function may be redefined to do something non trivial and is called
- whenever one of debugging macros fails (i.e. condition is false in an
- assertion)
-
- parameters:
- szFile and nLine - file name and line number of the ASSERT
- szMsg - optional message explaining the reason
- */
- extern void WXDLLEXPORT wxOnAssert(const wxChar *szFile,
- int nLine,
- const wxChar *szMsg = NULL);
-
- // call this function to break into the debugger uncodnitionally (assuming
- // the program is running under debugger, of course)
- extern void WXDLLEXPORT wxTrap();
-
- /*
- notice the usage of else at the end of wxASSERT macro: this ensures that
- the following code
-
- if ( ... )
- wxASSERT(...);
- else
- ...
-
- works like expected: if there were no "else", the one in the code above
- would be matched with a wrong "if"
- */
-
- // generic assert macro
- #define wxASSERT(cond) if ( !(cond) ) wxOnAssert(__TFILE__, __LINE__); else
-
- // assert with additional message explaining it's cause
- #define wxASSERT_MSG(cond, msg) \
- if ( !(cond) ) wxOnAssert(__TFILE__, __LINE__, msg); else
-
- // an assert helper used to avoid warning when testing constant expressions,
- // i.e. wxASSERT( sizeof(int) == 4 ) can generate a compiler warning about
- // expression being always true, but not using
- // wxASSERT( wxAssertIsEqual(sizeof(int), 4) )
- extern bool WXDLLEXPORT wxAssertIsEqual(int x, int y);
-#else
- #define wxTrap()
+/*
+ Assertion macros: check if the condition is true and call assert handler
+ (which will by default notify the user about failure) if it isn't.
- // nothing to do in release modes (hopefully at this moment there are
- // no more bugs ;-)
- #define wxASSERT(cond)
- #define wxASSERT_MSG(x, m)
-#endif //__WXDEBUG__
+ wxASSERT and wxFAIL macros as well as wxTrap() function do nothing at all
+ if wxDEBUG_LEVEL is 0 however they do check their conditions at default
+ debug level 1, unlike the previous wxWidgets versions.
-// Use of wxFalse instead of FALSE suppresses compiler warnings about testing
-// constant expression
-WXDLLEXPORT_DATA(extern const bool) wxFalse;
+ wxASSERT_LEVEL_2 is meant to be used for "expensive" asserts which should
+ normally be disabled because they have a big impact on performance and so
+ this macro only does anything if wxDEBUG_LEVEL >= 2.
+ */
+#if wxDEBUG_LEVEL
+ // call this function to break into the debugger unconditionally (assuming
+ // the program is running under debugger, of course)
+ extern void WXDLLIMPEXP_BASE wxTrap();
+
+ // assert checks if the condition is true and calls the assert handler with
+ // the provided message if it isn't
+ //
+ // NB: the macro is defined like this to ensure that nested if/else
+ // statements containing it are compiled in the same way whether it is
+ // defined as empty or not; also notice that we can't use ";" instead
+ // of "{}" as some compilers warn about "possible unwanted ;" then
+ #define wxASSERT_MSG(cond, msg) \
+ if ( !wxTheAssertHandler || (cond) ) \
+ {} \
+ else \
+ wxOnAssert(__FILE__, __LINE__, __WXFUNCTION__, #cond, msg)
-// special form of assert: always triggers it (in debug mode)
-#define wxFAIL wxASSERT(wxFalse)
+ // a version without any additional message, don't use unless condition
+ // itself is fully self-explanatory
+ #define wxASSERT(cond) wxASSERT_MSG(cond, (const char*)NULL)
-// FAIL with some message
-#define wxFAIL_MSG(msg) wxASSERT_MSG(wxFalse, msg)
+ // wxFAIL is a special form of assert: it always triggers (and so is
+ // usually used in normally unreachable code)
+ #define wxFAIL_COND_MSG(cond, msg) \
+ if ( !wxTheAssertHandler ) \
+ {} \
+ else \
+ wxOnAssert(__FILE__, __LINE__, __WXFUNCTION__, cond, msg)
+ #define wxFAIL_MSG(msg) wxFAIL_COND_MSG("Assert failure", msg)
+ #define wxFAIL wxFAIL_MSG((const char*)NULL)
+#else // !wxDEBUG_LEVEL
+ #define wxTrap()
+
+ #define wxASSERT(cond)
+ #define wxASSERT_MSG(cond, msg)
+ #define wxFAIL
+ #define wxFAIL_MSG(msg)
+ #define wxFAIL_COND_MSG(cond, msg)
+#endif // wxDEBUG_LEVEL
+
+#if wxDEBUG_LEVEL >= 2
+ #define wxASSERT_LEVEL_2_MSG(cond, msg) wxASSERT_MSG(cond, msg)
+ #define wxASSERT_LEVEL_2(cond) wxASSERT(cond)
+#else // wxDEBUG_LEVEL < 2
+ #define wxASSERT_LEVEL_2_MSG(cond, msg)
+ #define wxASSERT_LEVEL_2(cond)
+#endif
-// NB: the following macros work also in release mode!
/*
- These macros must be used only in invalid situation: for example, an
- invalid parameter (NULL pointer) is passed to a function. Instead of
- dereferencing it and causing core dump the function might try using
- CHECK( p != NULL ) or CHECK( p != NULL, return LogError("p is NULL!!") )
+ wxCHECK macros always check their conditions, setting debug level to 0 only
+ makes them silent in case of failure, otherwise -- including at default
+ debug level 1 -- they call the assert handler if the condition is false
+
+ They are supposed to be used only in invalid situation: for example, an
+ invalid parameter (e.g. a NULL pointer) is passed to a function. Instead of
+ dereferencing it and causing core dump the function might use
+
+ wxCHECK_RET( p != NULL, "pointer can't be NULL" )
*/
-// check that expression is true, "return" if not (also FAILs in debug mode)
-#define wxCHECK(x, rc) if (!(x)) {wxFAIL; return rc; }
+// the generic macro: takes the condition to check, the statement to be execute
+// in case the condition is false and the message to pass to the assert handler
+#define wxCHECK2_MSG(cond, op, msg) \
+ if ( cond ) \
+ {} \
+ else \
+ { \
+ wxFAIL_COND_MSG(#cond, msg); \
+ op; \
+ } \
+ struct wxDummyCheckStruct /* just to force a semicolon */
-// as wxCHECK but with a message explaining why we fail
-#define wxCHECK_MSG(x, rc, msg) if (!(x)) {wxFAIL_MSG(msg); return rc; }
+// check which returns with the specified return code if the condition fails
+#define wxCHECK_MSG(cond, rc, msg) wxCHECK2_MSG(cond, return rc, msg)
-// check that expression is true, perform op if not
-#define wxCHECK2(x, op) if (!(x)) {wxFAIL; op; }
+// check that expression is true, "return" if not (also FAILs in debug mode)
+#define wxCHECK(cond, rc) wxCHECK_MSG(cond, rc, (const char*)NULL)
-// as wxCHECK2 but with a message explaining why we fail
-#define wxCHECK2_MSG(x, op, msg) if (!(x)) {wxFAIL_MSG(msg); op; }
+// check that expression is true, perform op if not
+#define wxCHECK2(cond, op) wxCHECK2_MSG(cond, op, (const char*)NULL)
// special form of wxCHECK2: as wxCHECK, but for use in void functions
//
// there is no other way to tell the caller what exactly went wrong
// from the void function (of course, the function shouldn't be void
// to begin with...)
-#define wxCHECK_RET(x, msg) if (!(x)) {wxFAIL_MSG(msg); return; }
+#define wxCHECK_RET(cond, msg) wxCHECK2_MSG(cond, return, msg)
+
+
+// ----------------------------------------------------------------------------
+// Compile time asserts
+//
+// Unlike the normal assert and related macros above which are checked during
+// the program run-time the macros below will result in a compilation error if
+// the condition they check is false. This is usually used to check the
+// expressions containing sizeof()s which cannot be tested with the
+// preprocessor. If you can use the #if's, do use them as you can give a more
+// detailed error message then.
+// ----------------------------------------------------------------------------
+
+/*
+ How this works (you don't have to understand it to be able to use the
+ macros): we rely on the fact that it is invalid to define a named bit field
+ in a struct of width 0. All the rest are just the hacks to minimize the
+ possibility of the compiler warnings when compiling this macro: in
+ particular, this is why we define a struct and not an object (which would
+ result in a warning about unused variable) and a named struct (otherwise we'd
+ get a warning about an unnamed struct not used to define an object!).
+ */
+
+#define wxMAKE_UNIQUE_ASSERT_NAME wxMAKE_UNIQUE_NAME(wxAssert_)
+
+/*
+ The second argument of this macro must be a valid C++ identifier and not a
+ string. I.e. you should use it like this:
+
+ wxCOMPILE_TIME_ASSERT( sizeof(int) >= 2, YourIntsAreTooSmall );
+
+ It may be used both within a function and in the global scope.
+*/
+#if defined(__WATCOMC__)
+ /* avoid "unused symbol" warning */
+ #define wxCOMPILE_TIME_ASSERT(expr, msg) \
+ class wxMAKE_UNIQUE_ASSERT_NAME { \
+ unsigned int msg: expr; \
+ wxMAKE_UNIQUE_ASSERT_NAME() { wxUnusedVar(msg); } \
+ }
+#else
+ #define wxCOMPILE_TIME_ASSERT(expr, msg) \
+ struct wxMAKE_UNIQUE_ASSERT_NAME { unsigned int msg: expr; }
+#endif
+
+/*
+ When using VC++ 6 with "Edit and Continue" on, the compiler completely
+ mishandles __LINE__ and so wxCOMPILE_TIME_ASSERT() doesn't work, provide a
+ way to make "unique" assert names by specifying a unique prefix explicitly
+ */
+#define wxMAKE_UNIQUE_ASSERT_NAME2(text) wxCONCAT(wxAssert_, text)
+
+#define wxCOMPILE_TIME_ASSERT2(expr, msg, text) \
+ struct wxMAKE_UNIQUE_ASSERT_NAME2(text) { unsigned int msg: expr; }
+
+// helpers for wxCOMPILE_TIME_ASSERT below, for private use only
+#define wxMAKE_BITSIZE_MSG(type, size) type ## SmallerThan ## size ## Bits
+
+// a special case of compile time assert: check that the size of the given type
+// is at least the given number of bits
+#define wxASSERT_MIN_BITSIZE(type, size) \
+ wxCOMPILE_TIME_ASSERT(sizeof(type) * CHAR_BIT >= size, \
+ wxMAKE_BITSIZE_MSG(type, size))
+
+
+// ----------------------------------------------------------------------------
+// other miscellaneous debugger-related functions
+// ----------------------------------------------------------------------------
+
+/*
+ Return true if we're running under debugger.
+
+ Currently this only really works under Win32 and Mac in CodeWarrior builds,
+ it always returns false in other cases.
+ */
+#if defined(__WXMAC__) || defined(__WIN32__)
+ extern bool WXDLLIMPEXP_BASE wxIsDebuggerRunning();
+#else // !Mac
+ inline bool wxIsDebuggerRunning() { return false; }
+#endif // Mac/!Mac
+
+// An assert helper used to avoid warning when testing constant expressions,
+// i.e. wxASSERT( sizeof(int) == 4 ) can generate a compiler warning about
+// expression being always true, but not using
+// wxASSERT( wxAssertIsEqual(sizeof(int), 4) )
+//
+// NB: this is made obsolete by wxCOMPILE_TIME_ASSERT() and should no
+// longer be used.
+extern bool WXDLLIMPEXP_BASE wxAssertIsEqual(int x, int y);
+
+// Use of wxFalse instead of false suppresses compiler warnings about testing
+// constant expression
+extern WXDLLIMPEXP_DATA_BASE(const bool) wxFalse;
+
+#define wxAssertFailure wxFalse
+
+// This is similar to WXUNUSED() and useful for parameters which are only used
+// in assertions.
+#if wxDEBUG_LEVEL
+ #define WXUNUSED_UNLESS_DEBUG(param) param
+#else
+ #define WXUNUSED_UNLESS_DEBUG(param) WXUNUSED(param)
+#endif
-#endif // _WX_DEBUG_H_
+#endif // _WX_DEBUG_H_