Better fix for snprintf non-termination on windows.

core/include/fxcrt/fx_system.h

Index: core/include/fxcrt/fx_system.h
diff --git a/core/include/fxcrt/fx_system.h b/core/include/fxcrt/fx_system.h
index a875da5f9c6fb035a8c26730eb8ebd93672a1239..328fbb9fab1aced0d803b0857afae275c609e627 100644
--- a/core/include/fxcrt/fx_system.h
+++ b/core/include/fxcrt/fx_system.h
@@ -137,13 +137,17 @@ typedef FX_UINT64				FX_QWORD;
 #define FX_MAX(a, b) (((a) > (b)) ? (a) : (b))
 #define FX_MIN(a, b) (((a) < (b)) ? (a) : (b))
 #define FX_PI	3.1415926535897932384626433832795f
+
+// NOTE: never trust the return value from snprintf(), but provide versions
+// that always NUL-terminate.
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_

[brucedawson, 2015/04/10 18:03:02]

Consider making times version limited. When VS 2015 comes out we can switch to
the standard versions, and eventually eliminate this platform-specific mess. You
can do this by adding:

&& _MSC_VER < 1900

This would apply to the definition as well as the declaration.

[Tom Sepez, 2015/04/10 18:23:40]

Done.

-#define FXSYS_snprintf	_snprintf
-#define FXSYS_vsnprintf	_vsnprintf
+void FXSYS_snprintf(char *str, size_t size, const char* fmt, ...);

[brucedawson, 2015/04/10 18:03:02]

Consider adding SAL annotations that let /analyze do parameter checking. The
Linux versions will catch most bugs, but some format-string mismatches are
compiler specific. To do this just put _Printf_format_string_ in front of 'const
char*'. This may require #include <sal.h> - I can check that.

Not crucial, but it can be valuable, especially for 64-bit builds.

[Tom Sepez, 2015/04/10 18:23:40]

Done.

+void FXSYS_vsnprintf(char *str, size_t size, const char* fmt, va_list ap);
 #else
-#define FXSYS_snprintf	snprintf
-#define FXSYS_vsnprintf	vsnprintf
+#define FXSYS_snprintf	(void) snprintf
+#define FXSYS_vsnprintf	(void) vsnprintf
 #endif
+
 #define FXSYS_sprintf	DO_NOT_USE_SPRINTF_DIE_DIE_DIE
 #define FXSYS_vsprintf	DO_NOT_USE_VSPRINTF_DIE_DIE_DIE
 #define FXSYS_strchr	strchr