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git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@7212 e03df62e-2008-0410-955e-edbf42e46eb7

1 files changed, 13 insertions, 3 deletions

diff --git a/win/inspircd_memory_functions.cpp b/win/inspircd_memory_functions.cpp
index d487f69e3..ea4afa04c 100644
--- a/win/inspircd_memory_functions.cpp
+++ b/win/inspircd_memory_functions.cpp
@@ -1,14 +1,24 @@
-// Use the global heap for this process for all allocate/free operations.

 #include "inspircd_win32wrapper.h"

 #include <exception>

 #include <new>

 #include <new.h>

 

+/** On windows, all dll files and executables have their own private heap,

+ * whereas on POSIX systems, shared objects loaded into an executable share

+ * the executable's heap. This means that if we pass an arbitrary pointer to

+ * a windows DLL which is not allocated in that dll, without some form of

+ * marshalling, we get a page fault. To fix this, these overrided operators

+ * new and delete use the windows HeapAlloc and HeapFree functions to claim

+ * memory from the windows global heap. This makes windows 'act like' POSIX

+ * when it comes to memory usage between dlls and exes.

+ */

+

 void * ::operator new(size_t iSize)

 {

-	void* ptr = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, iSize);		// zero memory for unix compatibility

+	void* ptr = HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, iSize);		/* zero memory for unix compatibility */

 	/* This is the correct behaviour according to C++ standards for out of memory,

-	 * not returning null -- Brain*/

+	 * not returning null -- Brain

+	 */

 	if (!ptr)

 		throw std::bad_alloc();

 	else