diff --git a/sourcehook/sh_list.h b/sourcehook/sh_list.h
index d5f37e8..391df29 100644
--- a/sourcehook/sh_list.h
+++ b/sourcehook/sh_list.h
@@ -103,6 +103,20 @@ namespace SourceHook
 			insert(begin(), obj);
 		}
 
+		void push_sorted(const T &obj)
+		{
+			iterator iter;
+			for (iter = begin(); iter != end(); ++iter)
+			{
+				if (obj < *iter)
+				{
+					insert(iter, obj);
+					return;
+				}
+			}
+			push_back(obj);
+		}
+
 		size_t size() const
 		{
 			return m_Size;
@@ -301,6 +315,7 @@ namespace SourceHook
 			return *this;
 		}
 	};
+
 };	//NAMESPACE
 
 #endif //_INCLUDE_CSDM_LIST_H
diff --git a/sourcehook/sh_memory.h b/sourcehook/sh_memory.h
index d626bb9..a8e7077 100644
--- a/sourcehook/sh_memory.h
+++ b/sourcehook/sh_memory.h
@@ -43,6 +43,7 @@
 #		error Unsupported OS/Compiler
 # endif
 
+#include "sh_list.h"
 
 namespace SourceHook
 {
@@ -181,6 +182,258 @@ namespace SourceHook
 #endif
 		}
 	}
+
+	/*
+		Class which lets us allocate memory regions in special pages only meant for on the fly code generation.
+
+		If we alloc with malloc and then set the page access type to read/exec only, other regions returned by
+		malloc that are in the same page would lose their write access as well and the process could crash.
+
+		Allocating one page per code generation session is usually a waste of memory and on some plattforms also
+		a waste of virtual address space (Windows’ VirtualAlloc has a granularity of 64K).
+
+
+		IMPORTANT: the memory that Alloc() returns is not a in a defined state!
+		It could be in read+exec OR read+write mode.
+		-> call SetRE() or SetRW() before using allocated memory!
+	*/
+	class CPageAlloc
+	{
+		struct AllocationUnit
+		{
+			size_t begin_offset;
+			size_t size;
+
+			AllocationUnit(size_t p_offs, size_t p_size) : begin_offset(p_offs), size(p_size)
+			{
+			}
+
+			bool operator < (const AllocationUnit &other) const
+			{
+				return begin_offset < other.begin_offset;
+			}
+		};
+		
+		typedef List<AllocationUnit> AUList;
+
+		struct AllocatedRegion
+		{
+			void *startPtr;
+			size_t size;
+			bool isolated;					// may contain only one AU
+			AUList allocUnits;
+
+			bool TryAlloc(size_t reqsize, void * &outAddr)
+			{
+				// Check for isolated
+				if (isolated && !allocUnits.empty())
+					return false;
+
+				// Find the smallest gap where req fits
+				size_t lastend = 0;
+				size_t smallestgap_pos = size + 1;
+				size_t smallestgap_size = size + 1;
+
+				for (AUList::iterator iter = allocUnits.begin(); iter != allocUnits.end(); ++iter)
+				{
+					if (iter->begin_offset - lastend >= reqsize)
+					{
+						if (iter->begin_offset - lastend < smallestgap_size)
+						{
+							smallestgap_size = iter->begin_offset - lastend;
+							smallestgap_pos = lastend;
+						}
+					}
+					lastend = iter->begin_offset + iter->size;
+				}
+
+				if (size - lastend >= reqsize)
+				{
+					if (size - lastend < smallestgap_size)
+					{
+						smallestgap_size = size - lastend;
+						smallestgap_pos = lastend;
+					}
+				}
+
+				if (smallestgap_pos < size)
+				{
+					outAddr = reinterpret_cast<void*>(reinterpret_cast<char*>(startPtr) + smallestgap_pos);
+					allocUnits.push_sorted( AllocationUnit(smallestgap_pos, reqsize) );
+					return true;
+				}
+				else
+				{
+					return false;
+				}
+			}
+
+			bool TryFree(void *addr)
+			{
+				if (addr < startPtr || addr >= reinterpret_cast<void*>(reinterpret_cast<char*>(startPtr) + size))
+					return false;
+
+				size_t offs = reinterpret_cast<char*>(addr) - reinterpret_cast<char*>(startPtr);
+
+				for (AUList::iterator iter = allocUnits.begin(); iter != allocUnits.end(); ++iter)
+				{
+					if (iter->begin_offset == offs)
+					{
+						allocUnits.erase(iter);
+						return true;
+					}
+				}
+
+				return false;
+			}
+
+			bool Contains(void *addr)
+			{
+				return addr >= startPtr && addr < reinterpret_cast<void*>(reinterpret_cast<char*>(startPtr) + size);
+			}
+
+			void FreeRegion()
+			{
+#ifdef __linux__
+				munmap(startPtr, size);
+#else
+				VirtualFree(startPtr, 0, MEM_RELEASE);
+#endif
+			}
+		};
+
+		typedef List<AllocatedRegion> ARList;
+
+		size_t m_PageSize;
+		ARList m_Regions;
+
+		bool AddRegion(size_t minSize, bool isolated)
+		{
+			AllocatedRegion newRegion;
+			newRegion.startPtr = 0;
+			newRegion.isolated = isolated;
+
+			// Compute real size -> align up to m_PageSize boundary
+
+			newRegion.size = minSize - (minSize % m_PageSize);
+			if (newRegion.size < minSize)
+				newRegion.size += m_PageSize;
+
+#ifdef __linux__
+			newRegion.startPtr = mmap(0, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAN_ANONYMOUS, -1);
+#else
+			newRegion.startPtr = VirtualAlloc(NULL, newRegion.size, MEM_COMMIT, PAGE_READWRITE);
+#endif
+			
+			if (newRegion.startPtr)
+			{
+				m_Regions.push_back(newRegion);
+				return true;
+			}
+			else
+			{
+				return false;
+			}
+			
+		}
+
+		void *AllocPriv(size_t size, bool isolated)
+		{
+			void *addr;
+
+			if (!isolated)
+			{
+				for (ARList::iterator iter = m_Regions.begin(); iter != m_Regions.end(); ++iter)
+				{
+					if (iter->TryAlloc(size, addr))
+						return addr;
+				}
+			}
+
+			if (!AddRegion(size, isolated))
+				return NULL;
+			
+			bool tmp = m_Regions.back().TryAlloc(size, addr);
+			SH_ASSERT(tmp, ("TryAlloc fails after AddRegion"));
+			return addr;
+		}
+
+	public:
+		CPageAlloc()
+		{
+#ifdef __linux__
+			m_PageSize = sysconf(_SC_PAGESIZE);
+#else
+			SYSTEM_INFO sysInfo;
+			GetSystemInfo(&sysInfo);
+			m_PageSize = sysInfo.dwPageSize;
+#endif
+		}
+
+		~CPageAlloc()
+		{
+			// Free all regions
+			for (ARList::iterator iter = m_Regions.begin(); iter != m_Regions.end(); ++iter)
+			{
+				iter->FreeRegion();
+			}
+		}
+
+		void *Alloc(size_t size)
+		{
+			return AllocPriv(size, false);
+		}
+
+		void *AllocIsolated(size_t size)
+		{
+			return AllocPriv(size, true);
+		}
+
+		void Free(void *ptr)
+		{
+			for (ARList::iterator iter = m_Regions.begin(); iter != m_Regions.end(); ++iter)
+			{
+				if (iter->TryFree(ptr))
+				{
+					if (iter->allocUnits.empty())
+					{
+						iter->FreeRegion();
+						m_Regions.erase(iter);
+					}
+					break;
+				}
+			}
+		}
+
+		void SetRE(void *ptr)
+		{
+			for (ARList::iterator iter = m_Regions.begin(); iter != m_Regions.end(); ++iter)
+			{
+				if (iter->Contains(ptr))
+				{
+					SetMemAccess(iter->startPtr, iter->size, SH_MEM_READ | SH_MEM_EXEC);
+					break;
+				}
+			}
+		}
+
+		void SetRW(void *ptr)
+		{
+			for (ARList::iterator iter = m_Regions.begin(); iter != m_Regions.end(); ++iter)
+			{
+				if (iter->Contains(ptr))
+				{
+					SetMemAccess(iter->startPtr, iter->size, SH_MEM_READ | SH_MEM_WRITE);
+					break;
+				}
+			}
+		}
+
+		size_t GetPageSize()
+		{
+			return m_PageSize;
+		}
+	};
 }
 
 #endif
diff --git a/sourcehook/sourcehook_hookmangen.cpp b/sourcehook/sourcehook_hookmangen.cpp
index e00a50d..ef5c6a3 100644
--- a/sourcehook/sourcehook_hookmangen.cpp
+++ b/sourcehook/sourcehook_hookmangen.cpp
@@ -25,6 +25,8 @@ namespace SourceHook
 {
 	namespace Impl
 	{
+		CPageAlloc GenBuffer::ms_Allocator;
+
 		template <class T>
 		jit_int32_t DownCastPtr(T ptr)
 		{
@@ -1123,6 +1125,9 @@ namespace SourceHook
 			// m_HookfuncVfnPtr is a pointer to a void* because SH expects a pointer
 			// into the hookman's vtable
 			*m_HookfuncVfnptr = reinterpret_cast<void*>(m_HookFunc.GetData());
+
+			m_HookFunc.SetRE();
+
 			return m_HookFunc.GetData();
 		}
 
@@ -1211,8 +1216,7 @@ namespace SourceHook
 			IA32_Pop_Reg(&m_PubFunc, REG_EBP);
 			IA32_Return(&m_PubFunc);
 
-			SetMemAccess(reinterpret_cast<void*>(m_PubFunc.GetData()), m_PubFunc.GetSize(),
-				SH_MEM_READ | SH_MEM_EXEC);
+			m_PubFunc.SetRE();
 
 			return m_PubFunc;
 		}
diff --git a/sourcehook/sourcehook_hookmangen.h b/sourcehook/sourcehook_hookmangen.h
index 4bfeea7..1d95daf 100644
--- a/sourcehook/sourcehook_hookmangen.h
+++ b/sourcehook/sourcehook_hookmangen.h
@@ -42,84 +42,84 @@ namespace SourceHook
 
 		class GenBuffer
 		{
-			unsigned char *m_pData;
-			jitoffs_t m_Size;
-			jitoffs_t m_AllocatedSize;
-
-		public:
-			GenBuffer() : m_pData(NULL), m_Size(0), m_AllocatedSize(0)
-			{
-			}
-			~GenBuffer()
-			{
-				clear();
-			}
-			jitoffs_t GetSize()
-			{
-				return m_Size;
-			}
-			unsigned char *GetData()
-			{
-				return m_pData;
-			}
-
-			template <class PT> void push(PT what)
-			{
-				push((const unsigned char *)&what, sizeof(PT));
-			}
-
-			void push(const unsigned char *data, jitoffs_t size)
-			{
-				jitoffs_t newSize = m_Size + size;
-				if (newSize > m_AllocatedSize)
-				{
-					m_AllocatedSize = newSize > m_AllocatedSize*2 ? newSize : m_AllocatedSize*2;
-					if (m_AllocatedSize < 64)
-						m_AllocatedSize = 64;
-
-					unsigned char *newBuf;
-					try
-					{
-						//!!!! Better use of pages! or something!
-						newBuf = reinterpret_cast<unsigned char*>(VirtualAlloc(NULL, m_AllocatedSize, MEM_COMMIT, PAGE_READWRITE));
-					}
-					catch (std::bad_alloc)
-					{
-						newBuf = NULL;
-					}
-					if (!newBuf)
-					{
-						SH_ASSERT(0, ("bad_alloc: couldn't allocate 0x%08X bytes of memory\n", m_AllocatedSize));
-						return;
-					}
-					memcpy((void*)newBuf, (const void*)m_pData, m_Size);
-					if (m_pData)
-						VirtualFree(m_pData, 0, MEM_RELEASE);
-					m_pData = newBuf;
-				}
-				memcpy((void*)(m_pData + m_Size), (const void*)data, size);
-				m_Size = newSize;
-			}
-
-			template <class PT> void rewrite(jitoffs_t offset, PT what)
-			{
-				rewrite(offset, (const unsigned char *)&what, sizeof(PT));
-			}
-
-			void rewrite(jitoffs_t offset, const unsigned char *data, jitoffs_t size)
+			static CPageAlloc ms_Allocator;
+
+			unsigned char *m_pData;
+			jitoffs_t m_Size;
+			jitoffs_t m_AllocatedSize;
+
+		public:
+			GenBuffer() : m_pData(NULL), m_Size(0), m_AllocatedSize(0)
+			{
+			}
+			~GenBuffer()
+			{
+				clear();
+			}
+			jitoffs_t GetSize()
+			{
+				return m_Size;
+			}
+			unsigned char *GetData()
+			{
+				return m_pData;
+			}
+
+			template <class PT> void push(PT what)
+			{
+				push((const unsigned char *)&what, sizeof(PT));
+			}
+
+			void push(const unsigned char *data, jitoffs_t size)
+			{
+				jitoffs_t newSize = m_Size + size;
+				if (newSize > m_AllocatedSize)
+				{
+					m_AllocatedSize = newSize > m_AllocatedSize*2 ? newSize : m_AllocatedSize*2;
+					if (m_AllocatedSize < 64)
+						m_AllocatedSize = 64;
+
+					unsigned char *newBuf;
+					newBuf = reinterpret_cast<unsigned char*>(ms_Allocator.Alloc(m_AllocatedSize));
+					ms_Allocator.SetRW(newBuf);
+					if (!newBuf)
+					{
+						SH_ASSERT(0, ("bad_alloc: couldn't allocate 0x%08X bytes of memory\n", m_AllocatedSize));
+						return;
+					}
+					memcpy((void*)newBuf, (const void*)m_pData, m_Size);
+					if (m_pData)
+						ms_Allocator.Free(reinterpret_cast<void*>(m_pData));
+					m_pData = newBuf;
+				}
+				memcpy((void*)(m_pData + m_Size), (const void*)data, size);
+				m_Size = newSize;
+			}
+
+			template <class PT> void rewrite(jitoffs_t offset, PT what)
+			{
+				rewrite(offset, (const unsigned char *)&what, sizeof(PT));
+			}
+
+			void rewrite(jitoffs_t offset, const unsigned char *data, jitoffs_t size)
 			{
 				SH_ASSERT(offset + size <= m_AllocatedSize, ("rewrite too far"));
 
 				memcpy((void*)(m_pData + offset), (const void*)data, size);
-			}
-
-			void clear()
-			{
-				if (m_pData)
-					VirtualFree(m_pData, 0, MEM_RELEASE);
-				m_pData = NULL;
-				m_Size = 0;
-				m_AllocatedSize = 0;
+			}
+
+			void clear()
+			{
+				if (m_pData)
+					ms_Allocator.Free(reinterpret_cast<void*>(m_pData));
+				m_pData = NULL;
+				m_Size = 0;
+				m_AllocatedSize = 0;
+			}
+
+			void SetRE()
+			{
+				ms_Allocator.SetRE(reinterpret_cast<void*>(m_pData));
 			}
 
 			operator unsigned char *()
@@ -149,7 +149,6 @@ namespace SourceHook
 			{
 				offs = get_outputpos() - offs;
 			}
-			// :TODO: real buffer which uses virtualalloc correctly	
 		};
 
 		class GenContext
diff --git a/sourcehook/test/main.cpp b/sourcehook/test/main.cpp
index c7946bf..bdf3216 100644
--- a/sourcehook/test/main.cpp
+++ b/sourcehook/test/main.cpp
@@ -47,6 +47,7 @@ DECL_TEST(Ref);
 DECL_TEST(RefRet);
 DECL_TEST(VPHooks);
 DECL_TEST(HookManGen);
+DECL_TEST(CPageAlloc);					// in testhookmangen.cpp
 
 int main(int argc, char *argv[])
 {
@@ -70,6 +71,7 @@ int main(int argc, char *argv[])
 	DO_TEST(RefRet);
 	DO_TEST(VPHooks);
 	DO_TEST(HookManGen);
+	DO_TEST(CPageAlloc);
 
 	cout << endl << "----" << endl << "Passed: " << passed << endl << "Failed: " << failed << endl;
 	cout << "Total: " << passed + failed << endl;
diff --git a/sourcehook/test/msvc8/test.vcproj b/sourcehook/test/msvc8/test.vcproj
index ae768e5..a11c8e1 100644
--- a/sourcehook/test/msvc8/test.vcproj
+++ b/sourcehook/test/msvc8/test.vcproj
@@ -371,6 +371,10 @@
 				RelativePath="..\..\sourcehook.cpp"
 				>
 			</File>
+			<File
+				RelativePath="..\..\sourcehook_hookmangen.cpp"
+				>
+			</File>
 			<File
 				RelativePath="..\test1.cpp"
 				>
@@ -395,6 +399,10 @@
 				RelativePath="..\testbail2.cpp"
 				>
 			</File>
+			<File
+				RelativePath="..\testhookmangen.cpp"
+				>
+			</File>
 			<File
 				RelativePath="..\testlist.cpp"
 				>
@@ -431,6 +439,10 @@
 				RelativePath="..\testrefret.cpp"
 				>
 			</File>
+			<File
+				RelativePath="..\testvphooks.cpp"
+				>
+			</File>
 		</Filter>
 		<Filter
 			Name="Header Files"
@@ -440,6 +452,10 @@
 				RelativePath="..\..\sh_list.h"
 				>
 			</File>
+			<File
+				RelativePath="..\..\sh_memory.h"
+				>
+			</File>
 			<File
 				RelativePath="..\..\sh_stack.h"
 				>
@@ -460,6 +476,14 @@
 				RelativePath="..\..\sourcehook.h"
 				>
 			</File>
+			<File
+				RelativePath="..\..\sourcehook_hookmangen.h"
+				>
+			</File>
+			<File
+				RelativePath="..\..\sourcehook_hookmangen_x86.h"
+				>
+			</File>
 			<File
 				RelativePath="..\..\sourcehook_impl.h"
 				>
@@ -500,6 +524,10 @@
 						/>
 					</FileConfiguration>
 				</File>
+				<File
+					RelativePath="..\testhookmangen.hxx"
+					>
+				</File>
 			</Filter>
 		</Filter>
 		<Filter
diff --git a/sourcehook/test/testhookmangen.cpp b/sourcehook/test/testhookmangen.cpp
index 76646d6..ab0557a 100644
--- a/sourcehook/test/testhookmangen.cpp
+++ b/sourcehook/test/testhookmangen.cpp
@@ -3,6 +3,7 @@
 #include "sourcehook_test.h"
 #include "testevents.h"
 #include "sourcehook_hookmangen.h"
+#include "sh_memory.h"
 
 // TESTHOOKMANGEN
 // Test automatic hookman generation
@@ -268,7 +269,6 @@ namespace
 	THGM_SETUP_RI(105, double, SourceHook::PassInfo::PassType_Float, SourceHook::PassInfo::PassFlag_ByVal);
 }
 
-
 bool TestHookManGen(std::string &error)
 {
 	GET_SHPTR(g_SHPtr);
@@ -468,3 +468,73 @@ bool TestHookManGen(std::string &error)
 	Test_CompleteShutdown(g_SHPtr);
 	return true;
 }
+
+bool TestCPageAlloc(std::string &error)
+{
+	using namespace SourceHook;
+
+	CPageAlloc alloc;
+	int i;
+	size_t ps = alloc.GetPageSize();
+
+	char *test1[8];
+
+	for (i = 0; i < 8; ++i)
+		test1[i] = (char*) alloc.Alloc(ps / 4);
+
+	CHECK_COND(test1[1] == test1[0] + ps/4, "Part 1.1");
+	CHECK_COND(test1[2] == test1[1] + ps/4, "Part 1.2");
+	CHECK_COND(test1[3] == test1[2] + ps/4, "Part 1.3");
+
+	CHECK_COND(test1[5] == test1[4] + ps/4, "Part 1.4");
+	CHECK_COND(test1[6] == test1[5] + ps/4, "Part 1.5");
+	CHECK_COND(test1[7] == test1[6] + ps/4, "Part 1.6");
+
+	void *test2 = alloc.Alloc(ps * 3);
+
+	alloc.SetRW(test2);
+	memset(test2, 0, ps * 3);			// should not crash :)
+	alloc.SetRE(test2);
+
+	alloc.Free(test2);
+
+	// Dealloc a ps/4 block and place two ps/8 blocks into it
+	alloc.Free(test1[2]);
+
+	char *test3[2];
+	test3[0] = (char*) alloc.Alloc(ps / 8);
+	test3[1] = (char*) alloc.Alloc(ps / 8);
+
+	CHECK_COND(test3[0] == test1[2], "Part 2.1");
+	CHECK_COND(test3[1] == test1[2] + ps/8, "Part 2.2");
+
+	// Isolated
+	char *test4[8];
+	for (i = 0; i < 8; ++i)
+		test4[i] = (char*) alloc.AllocIsolated(ps / 4);
+
+	// -> The difference is at least one page
+	CHECK_COND(static_cast<size_t>(abs(test4[1] - test4[0])) >= ps, "Part 3.1");
+	CHECK_COND(static_cast<size_t>(abs(test4[2] - test4[1])) >= ps, "Part 3.2");
+	CHECK_COND(static_cast<size_t>(abs(test4[3] - test4[2])) >= ps, "Part 3.3");
+
+	CHECK_COND(static_cast<size_t>(abs(test4[5] - test4[4])) >= ps, "Part 3.4");
+	CHECK_COND(static_cast<size_t>(abs(test4[6] - test4[5])) >= ps, "Part 3.5");
+	CHECK_COND(static_cast<size_t>(abs(test4[7] - test4[6])) >= ps, "Part 3.6");
+
+	// Thus i can set everything except for test4[2] to RE and still write to test4[2]
+
+	alloc.SetRW(test4[2]);
+
+	alloc.SetRE(test4[0]);
+	alloc.SetRE(test4[1]);
+	alloc.SetRE(test4[3]);
+	alloc.SetRE(test4[4]);
+	alloc.SetRE(test4[5]);
+	alloc.SetRE(test4[6]);
+	alloc.SetRE(test4[7]);
+
+	memset((void*)test4[2], 0, ps / 4);
+
+	return true;
+}
\ No newline at end of file