Added configure test for const_cast<>(), and enabled it

[wxWidgets.git] / include / wx / debug.h

diff --git a/include/wx/debug.h b/include/wx/debug.h
index 4fd54e2d91a1673bcef9a3b2acfcc37796cd857b..1c3ab43818f228bf66c42cdac801114a22daed37 100644 (file)
--- a/include/wx/debug.h
+++ b/include/wx/debug.h
@@ -12,9 +12,38 @@
 #ifndef   _WX_DEBUG_H_
 #define   _WX_DEBUG_H_
 
 #ifndef   _WX_DEBUG_H_
 #define   _WX_DEBUG_H_
 

+#ifndef __WXWINCE__

 #include  <assert.h>
 #include  <assert.h>

+#endif
+#include  <limits.h>            // for CHAR_BIT used below

 
 

-#include  "wx/wxchar.h"
+#include  "wx/wxchar.h"         // for __TFILE__ and wxChar
+
+// ----------------------------------------------------------------------------
+// Defines controlling the debugging macros
+// ----------------------------------------------------------------------------
+
+// if _DEBUG is defined (MS VC++ and others use it in debug builds), define
+// __WXDEBUG__ too
+#ifdef _DEBUG
+    #ifndef __WXDEBUG__
+        #define __WXDEBUG__
+    #endif // !__WXDEBUG__
+#endif // _DEBUG
+
+// if NDEBUG is defined (<assert.h> uses it), undef __WXDEBUG__ and WXDEBUG
+#ifdef NDEBUG
+    #undef __WXDEBUG__
+    #undef WXDEBUG
+#endif // NDEBUG
+
+// if __WXDEBUG__ is defined, make sure that WXDEBUG is defined and >= 1
+#ifdef __WXDEBUG__
+    #if !defined(WXDEBUG) || !WXDEBUG
+        #undef WXDEBUG
+        #define WXDEBUG 1
+    #endif // !WXDEBUG
+#endif // __WXDEBUG__

 
 // ----------------------------------------------------------------------------
 // Debugging macros
 
 // ----------------------------------------------------------------------------
 // Debugging macros


@@ -36,11 +65,9 @@
 // a judicious use of them might increase your program's stability.
 // ----------------------------------------------------------------------------
 
 // a judicious use of them might increase your program's stability.
 // ----------------------------------------------------------------------------
 

-// Use of these suppresses compiler warnings about testing constant expression
-WXDLLEXPORT_DATA(extern const bool) wxTrue;
-WXDLLEXPORT_DATA(extern const bool) wxFalse;
-

 // Macros which are completely disabled in 'release' mode
 // 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
 #ifdef  __WXDEBUG__
   /*
     this function may be redefined to do something non trivial and is called


@@ -51,39 +78,60 @@ WXDLLEXPORT_DATA(extern const bool) wxFalse;
        szFile and nLine - file name and line number of the ASSERT
        szMsg            - optional message explaining the reason
   */
        szFile and nLine - file name and line number of the ASSERT
        szMsg            - optional message explaining the reason
   */

-  void WXDLLEXPORT wxOnAssert(const wxChar *szFile, int nLine, const wxChar *szMsg = (const wxChar *) NULL);
-
-  /*
-    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"
-  */
+  extern void WXDLLEXPORT wxOnAssert(const wxChar *szFile,
+                                     int nLine,
+                                     const wxChar *szCond,
+                                     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();
+
+  // helper function used to implement wxASSERT and wxASSERT_MSG
+  //
+  // note using "int" and not "bool" for cond to avoid VC++ warnings about
+  // implicit conversions when doing "wxAssert( pointer )" and also use of
+  // "!!cond" below to ensure that everything is converted to int
+  extern void WXDLLEXPORT wxAssert(int cond,
+                                   const wxChar *szFile,
+                                   int nLine,
+                                   const wxChar *szCond,
+                                   const wxChar *szMsg = NULL) ;

 
   // generic assert macro
 
   // generic assert macro

-  #define wxASSERT(cond) if ( !(cond) ) wxOnAssert(__TFILE__, __LINE__); else
+  #define wxASSERT(cond) wxAssert(!!(cond), __TFILE__, __LINE__, _T(#cond))

 
   // assert with additional message explaining it's cause
   #define wxASSERT_MSG(cond, msg) \
 
   // assert with additional message explaining it's cause
   #define wxASSERT_MSG(cond, msg) \

-                    if ( !(cond) ) wxOnAssert(__TFILE__, __LINE__, msg); else
+    wxAssert(!!(cond), __TFILE__, __LINE__, _T(#cond), msg)
+
+  // 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 shouldn't be
+  //     used any longer
+  extern bool WXDLLEXPORT wxAssertIsEqual(int x, int y);

 #else
 #else

+  #define wxTrap()
+

   // 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__
 
   // 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__
 

+// Use of wxFalse instead of FALSE suppresses compiler warnings about testing
+// constant expression
+WXDLLEXPORT_DATA(extern const bool) wxFalse;
+#define wxAssertFailure wxFalse
+

 // special form of assert: always triggers it (in debug mode)
 // special form of assert: always triggers it (in debug mode)

-#define wxFAIL                 wxASSERT(wxFalse)
+#define wxFAIL                 wxASSERT(wxAssertFailure)

 
 // FAIL with some message
 
 // FAIL with some message

-#define wxFAIL_MSG(msg)        wxASSERT_MSG(wxFalse, msg)
+#define wxFAIL_MSG(msg)        wxASSERT_MSG(wxAssertFailure, msg)

 
 // NB: the following macros work also in release mode!
 
 
 // NB: the following macros work also in release mode!
 


@@ -107,11 +155,68 @@ WXDLLEXPORT_DATA(extern const bool) wxFalse;
 #define wxCHECK2_MSG(x, op, msg)  if (!(x)) {wxFAIL_MSG(msg); op; }
 
 // special form of wxCHECK2: as wxCHECK, but for use in void functions
 #define wxCHECK2_MSG(x, op, msg)  if (!(x)) {wxFAIL_MSG(msg); op; }
 
 // special form of wxCHECK2: as wxCHECK, but for use in void functions

-//  NB: there is only one form (with msg parameter) and it's intentional:
-//      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...)
+//
+// NB: there is only one form (with msg parameter) and it's intentional:
+//     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(x, msg)       if (!(x)) {wxFAIL_MSG(msg); return; }
 

+// ----------------------------------------------------------------------------
+// Compile time asserts
+//
+// Unlike the normal assert and related macros above which are checked during
+// the program tun-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!).
+  The _n__ part is to stop VC++ 7 being confused since it encloses __LINE++ in
+  parentheses. Unfortunately this does not work with other compilers, so
+  we will only enable it when we know the _precise_ symbols to test for.
+ */
+
+#define wxMAKE_ASSERT_NAME_HELPER(line)     wxAssert_ ## line
+#define wxMAKE_ASSERT_NAME(line)            wxMAKE_ASSERT_NAME_HELPER(line)
+#if 0
+#define wxMAKE_UNIQUE_ASSERT_NAME           wxMAKE_ASSERT_NAME(_n___ ## __LINE__)
+#else
+#define wxMAKE_UNIQUE_ASSERT_NAME           wxMAKE_ASSERT_NAME(__LINE__)
+#endif
+#define wxMAKE_UNIQUE_ASSERT_NAME2(text)    wxMAKE_ASSERT_NAME(text)
+
+/*
+  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.
+*/
+#define wxCOMPILE_TIME_ASSERT(expr, msg) \
+    struct wxMAKE_UNIQUE_ASSERT_NAME { unsigned int msg: expr; }
+
+#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))
+

 #endif  // _WX_DEBUG_H_
 
 #endif  // _WX_DEBUG_H_