Document a bit the tricky symbol definition for windows, and remove useless tabs

[simgrid.git] / include / xbt / misc.h

diff --git a/include/xbt/misc.h b/include/xbt/misc.h
index a49fbf0..1866117 100644 (file)
--- a/include/xbt/misc.h
+++ b/include/xbt/misc.h
@@ -56,47 +56,53 @@
 #    define XBT_INLINE  inline
 #endif
 
-/* Windows __declspec(). */
-#if defined(_WIN32) && defined(__BORLANDC__)
-#  if(__BORLANDC__ < 0x540)
-#    if (defined (__DLL) || defined (_DLL) || defined (_WINDLL) || defined (_RTLDLL) || defined (_XBT_USE_DYNAMIC_LIB) ) && ! defined (_XBT_USE_STAT
-#      undef  _XBT_USE_DECLSPEC
-#      define _XBT_USE_DECLSPEC
-#    endif
-#  else
-#  if ( defined (__DLL) || defined (_DLL) || defined (_WINDLL) || defined (_RTLDLL) || defined(_AFXDLL) || defined (_XBT_USE_DYNAMIC_LIB) )
-#    undef  _XBT_USE_DECLSPEC
-#    define _XBT_USE_DECLSPEC 1
-#  endif
-#  endif
+/* 
+ * Function calling convention (not used for now) 
+ */
+ 
+#ifdef _WIN32
+#  ifndef _XBT_CALL
+#    define _XBT_CALL __cdecl
+#   endif
+#else 
+#  define _XBT_CALL
 #endif
 
-#if defined (_XBT_USE_DECLSPEC) /* using export/import technique */
-
-#    ifndef _XBT_EXPORT_DECLSPEC
-#        define _XBT_EXPORT_DECLSPEC
-#    endif
-
-#    ifndef _XBT_IMPORT_DECLSPEC
-#        define _XBT_IMPORT_DECLSPEC
-#    endif
-
-#    if defined (_XBT_DESIGNATED_DLL) /* this is a lib which will contain xbt exports */
-#        define  XBT_PUBLIC        _XBT_EXPORT_DECLSPEC
+/* Handle import/export stuff
+ * 
+ * Rational of XBT_PUBLIC: 
+ *   * If you build the DLL you must pass the right value of XBT_PUBLIC in the project : to do this you must define the DLL_EXPORT macro
+ *   * If you do a static compilation, you must define the macro DLL_STATIC
+ *   * If you link your code against the DLL, this file defines the macro to '__declspec(dllimport)' for you
+ *   * If you compile under unix, this file defines the macro to 'extern', even if it's not mandatory with modern compilers
+ * 
+ * Rational of XBT_PUBLIC_NO_IMPORT:
+ *   * This is for symbols which must be exported in the DLL, but not imported from it. 
+ *     This is obviously useful for initialized globals (which cannot be extern or similar).
+ *     This is also used in the log mecanism where a macro creates the variable automatically.
+ *      When the macro is called from within SimGrid, the symbol must be exported, but when called 
+ *      from within the client code, it must not try to retrieve the symbol from the DLL since it's not in there.
+ */
+
+
+#ifdef DLL_EXPORT
+#  define XBT_PUBLIC(type)                   __declspec(dllexport) type
+#  define XBT_PUBLIC_NO_IMPORT(type)  __declspec(dllexport) type
+#else
+#  ifdef DLL_STATIC
+#    define XBT_PUBLIC(type)          type
+#    define XBT_PUBLIC_NO_IMPORT(type) type
+#  else
+#    ifdef _WIN32
+#      define XBT_PUBLIC(type)          __declspec(dllimport) type 
+#      define XBT_PUBLIC_NO_IMPORT(type) type
 #    else
-#        define  XBT_PUBLIC        _XBT_IMPORT_DECLSPEC   /* other modules, importing xbt exports */
+#      define XBT_PUBLIC(type)           extern type
+#      define XBT_PUBLIC_NO_IMPORT(type) type
 #    endif
-
-#else /* not using DLL export/import specifications */
-
-#    define XBT_PUBLIC
-
-#endif /* #if defined (_XBT_USE_DECLSPEC) */
-
-/* Function calling convention (not used for now) */
-#if !defined (_XBT_CALL)
-#define _XBT_CALL
-#endif
+#  endif
+#endif 
+   
 
 
 
@@ -132,10 +138,14 @@
 
 SG_BEGIN_DECL()
 
-XBT_PUBLIC const char *xbt_procname(void);
+XBT_PUBLIC(const char *)xbt_procname(void);
 
 #define XBT_BACKTRACE_SIZE 10 /* FIXME: better place? Do document */
    
 SG_END_DECL()
 
 #endif /* XBT_MISC_H */
+
+
+
+