nuclear@0: /************************************************************************************
nuclear@0: 
nuclear@0: Filename    :   OVR_Allocator.cpp
nuclear@0: Content     :   Installable memory allocator implementation
nuclear@0: Created     :   September 19, 2012
nuclear@0: Notes       : 
nuclear@0: 
nuclear@0: Copyright   :   Copyright 2014 Oculus VR, LLC All Rights reserved.
nuclear@0: 
nuclear@0: Licensed under the Oculus VR Rift SDK License Version 3.2 (the "License"); 
nuclear@0: you may not use the Oculus VR Rift SDK except in compliance with the License, 
nuclear@0: which is provided at the time of installation or download, or which 
nuclear@0: otherwise accompanies this software in either electronic or hard copy form.
nuclear@0: 
nuclear@0: You may obtain a copy of the License at
nuclear@0: 
nuclear@0: http://www.oculusvr.com/licenses/LICENSE-3.2 
nuclear@0: 
nuclear@0: Unless required by applicable law or agreed to in writing, the Oculus VR SDK 
nuclear@0: distributed under the License is distributed on an "AS IS" BASIS,
nuclear@0: WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
nuclear@0: See the License for the specific language governing permissions and
nuclear@0: limitations under the License.
nuclear@0: 
nuclear@0: ************************************************************************************/
nuclear@0: 
nuclear@0: #include "OVR_Allocator.h"
nuclear@0: #ifdef OVR_OS_MAC
nuclear@0:  #include <stdlib.h>
nuclear@0: #else
nuclear@0:  #include <malloc.h>
nuclear@0: #endif
nuclear@0: 
nuclear@0: #if defined(OVR_OS_MS)
nuclear@0:  #include <Windows.h>
nuclear@0: #elif defined(OVR_OS_MAC) || defined(OVR_OS_UNIX)
nuclear@0:  #include <unistd.h>
nuclear@0:  #include <sys/mman.h>
nuclear@0: #endif
nuclear@0: 
nuclear@0: 
nuclear@0: namespace OVR {
nuclear@0: 
nuclear@0: //-----------------------------------------------------------------------------------
nuclear@0: // ***** Allocator
nuclear@0: 
nuclear@0: Allocator* Allocator::pInstance = 0;
nuclear@0: 
nuclear@0: // Default AlignedAlloc implementation will delegate to Alloc/Free after doing rounding.
nuclear@0: void* Allocator::AllocAligned(size_t size, size_t align)
nuclear@0: {
nuclear@0:     OVR_ASSERT((align & (align-1)) == 0);
nuclear@0:     align = (align > sizeof(size_t)) ? align : sizeof(size_t);
nuclear@0:     size_t p = (size_t)Alloc(size+align);
nuclear@0:     size_t aligned = 0;
nuclear@0:     if (p)
nuclear@0:     {
nuclear@0:         aligned = (size_t(p) + align-1) & ~(align-1);
nuclear@0:         if (aligned == p) 
nuclear@0:             aligned += align;
nuclear@0:         *(((size_t*)aligned)-1) = aligned-p;
nuclear@0:     }
nuclear@0:     return (void*)aligned;
nuclear@0: }
nuclear@0: 
nuclear@0: void Allocator::FreeAligned(void* p)
nuclear@0: {
nuclear@0:     size_t src = size_t(p) - *(((size_t*)p)-1);
nuclear@0:     Free((void*)src);
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: //------------------------------------------------------------------------
nuclear@0: // ***** Default Allocator
nuclear@0: 
nuclear@0: // This allocator is created and used if no other allocator is installed.
nuclear@0: // Default allocator delegates to system malloc.
nuclear@0: 
nuclear@0: void* DefaultAllocator::Alloc(size_t size)
nuclear@0: {
nuclear@0:     return malloc(size);
nuclear@0: }
nuclear@0: void* DefaultAllocator::AllocDebug(size_t size, const char* file, unsigned line)
nuclear@0: {
nuclear@0: 	OVR_UNUSED2(file, line); // should be here for debugopt config
nuclear@0: #if defined(OVR_CC_MSVC) && defined(_CRTDBG_MAP_ALLOC)
nuclear@0:     return _malloc_dbg(size, _NORMAL_BLOCK, file, line);
nuclear@0: #else
nuclear@0:     return malloc(size);
nuclear@0: #endif
nuclear@0: }
nuclear@0: 
nuclear@0: void* DefaultAllocator::Realloc(void* p, size_t newSize)
nuclear@0: {
nuclear@0:     return realloc(p, newSize);
nuclear@0: }
nuclear@0: void DefaultAllocator::Free(void *p)
nuclear@0: {
nuclear@0:     return free(p);
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: void* MMapAlloc(size_t size)
nuclear@0: {
nuclear@0:     #if defined(OVR_OS_MS)
nuclear@0:         return VirtualAlloc(NULL, size, MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE); // size is rounded up to a page. // Returned memory is 0-filled.
nuclear@0: 
nuclear@0:     #elif defined(OVR_OS_MAC) || defined(OVR_OS_UNIX)
nuclear@0:         #if !defined(MAP_FAILED)
nuclear@0:             #define MAP_FAILED ((void*)-1)
nuclear@0:         #endif
nuclear@0: 
nuclear@0:         void* result = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); // Returned memory is 0-filled.
nuclear@0:         if(result == MAP_FAILED) // mmap returns MAP_FAILED (-1) upon failure.
nuclear@0:             result = NULL;
nuclear@0:         return result;
nuclear@0:     #endif
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: void MMapFree(void* memory, size_t size)
nuclear@0: {
nuclear@0:     #if defined(OVR_OS_MS)
nuclear@0:         OVR_UNUSED(size);
nuclear@0:         VirtualFree(memory, 0, MEM_RELEASE);
nuclear@0: 
nuclear@0:     #elif defined(OVR_OS_MAC) || defined(OVR_OS_UNIX)
nuclear@0:         size_t pageSize = getpagesize();
nuclear@0:         size = (((size + (pageSize - 1)) / pageSize) * pageSize);
nuclear@0:         munmap(memory, size); // Must supply the size to munmap.
nuclear@0:     #endif
nuclear@0: }
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: 
nuclear@0: } // OVR