From c78a8595fbb4c94855ca0a2c5ed93b1c25bf5cce Mon Sep 17 00:00:00 2001
From: David Williams <david@volumesoffun.com>
Date: Wed, 26 Dec 2012 01:33:05 +0000
Subject: [PATCH] Initial work on new assert macro.

---
 library/PolyVoxCore/CMakeLists.txt            |  2 +
 .../include/PolyVoxCore/Impl/ErrorHandling.h  | 77 +++++++++++++++++++
 .../polyvoxcore/source/Impl/ErrorHandling.cpp | 70 +++++++++++++++++
 3 files changed, 149 insertions(+)
 create mode 100644 library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
 create mode 100644 library/polyvoxcore/source/Impl/ErrorHandling.cpp

diff --git a/library/PolyVoxCore/CMakeLists.txt b/library/PolyVoxCore/CMakeLists.txt
index 614e05d7..201d8ab5 100644
--- a/library/PolyVoxCore/CMakeLists.txt
+++ b/library/PolyVoxCore/CMakeLists.txt
@@ -94,6 +94,7 @@ SET(CORE_INC_FILES
 )
 
 SET(IMPL_SRC_FILES
+	source/Impl/ErrorHandling.cpp
 	source/Impl/MarchingCubesTables.cpp
 	source/Impl/RandomUnitVectors.cpp
 	source/Impl/RandomVectors.cpp
@@ -106,6 +107,7 @@ SET(IMPL_INC_FILES
 	include/PolyVoxCore/Impl/AStarPathfinderImpl.h
 	include/PolyVoxCore/Impl/Block.h
 	include/PolyVoxCore/Impl/Block.inl
+	include/PolyVoxCore/Impl/ErrorHandling.h
 	include/PolyVoxCore/Impl/MarchingCubesTables.h
 	include/PolyVoxCore/Impl/RandomUnitVectors.h
 	include/PolyVoxCore/Impl/RandomVectors.h
diff --git a/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h b/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
new file mode 100644
index 00000000..c3f832a3
--- /dev/null
+++ b/library/PolyVoxCore/include/PolyVoxCore/Impl/ErrorHandling.h
@@ -0,0 +1,77 @@
+/*******************************************************************************
+Copyright (c) 2005-2009 David Williams
+
+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 __PolyVox_ErrorHandling_H__
+#define __PolyVox_ErrorHandling_H__
+
+#define POLYVOX_ASSERTS_ENABLED
+
+namespace PolyVox
+{
+	namespace Assert
+	{
+		enum FailBehavior
+		{
+			Halt,
+			Continue,
+		};
+
+		typedef FailBehavior (*Handler)(const char* condition, const char* msg, const char* file, int line);
+
+		Handler GetHandler();
+		void SetHandler(Handler newHandler);
+
+		FailBehavior ReportFailure(const char* condition, 
+								   const char* file, 
+								   int line, 
+								   const char* msg, ...);
+	}
+}
+
+#define POLYVOX_HALT() __debugbreak()
+#define POLYVOX_UNUSED(x) do { (void)sizeof(x); } while(0)
+
+#ifdef POLYVOX_ASSERTS_ENABLED
+
+	#define POLYVOX_ASSERT(cond, msg, ...) \
+		do \
+		{ \
+			if (!(cond)) \
+			{ \
+				if (PolyVox::Assert::ReportFailure(#cond, __FILE__, __LINE__, (msg), __VA_ARGS__) == \
+					PolyVox::Assert::Halt) \
+					POLYVOX_HALT(); \
+			} \
+		} while(0)
+
+#else
+	
+	#define POLYVOX_ASSERT(condition, msg, ...) \
+		do { POLYVOX_UNUSED(condition); POLYVOX_UNUSED(msg); } while(0)
+	
+#endif
+
+#define POLYVOX_STATIC_ASSERT(x) \
+	typedef char polyvoxStaticAssert[(x) ? 1 : -1];
+
+#endif //__PolyVox_ErrorHandling_H__
diff --git a/library/polyvoxcore/source/Impl/ErrorHandling.cpp b/library/polyvoxcore/source/Impl/ErrorHandling.cpp
new file mode 100644
index 00000000..40225a44
--- /dev/null
+++ b/library/polyvoxcore/source/Impl/ErrorHandling.cpp
@@ -0,0 +1,70 @@
+#include "PolyVoxCore/Impl/ErrorHandling.h"
+
+#include <cstdio>
+#include <cstdarg>
+
+namespace PolyVox
+{
+
+namespace
+{
+
+Assert::FailBehavior DefaultHandler(const char* condition, 
+									const char* msg, 
+									const char* file, 
+									const int line)
+{
+	std::printf("%s(%d): Assert Failure: ", file, line);
+	
+	if (condition != NULL)
+		std::printf("'%s' ", condition);
+
+	if (msg != NULL)
+		std::printf("%s", msg);
+
+	std::printf("\n");
+
+	return Assert::Halt;
+}
+
+Assert::Handler& GetAssertHandlerInstance()
+{
+	static Assert::Handler s_handler = &DefaultHandler;
+	return s_handler;
+}
+
+}
+
+Assert::Handler Assert::GetHandler()
+{
+	return GetAssertHandlerInstance();
+}
+
+void Assert::SetHandler(Assert::Handler newHandler)
+{
+	GetAssertHandlerInstance() = newHandler;
+}
+
+Assert::FailBehavior Assert::ReportFailure(const char* condition, 
+										   const char* file, 
+										   const int line, 
+										   const char* msg, ...)
+{
+	const char* message = NULL;
+	if (msg != NULL)
+	{
+		char messageBuffer[1024];
+		{
+			va_list args;
+			va_start(args, msg);
+			vsnprintf(messageBuffer, 1024, msg, args);
+			va_end(args);
+		}
+
+		message = messageBuffer;
+	}
+
+	return GetAssertHandlerInstance()(condition, message, file, line);
+}
+
+}
\ No newline at end of file