1// tMemory.cpp 
2// 
3// Tacent memory management API. 
4// 
5// Copyright (c) 2004-2006, 2017 Tristan Grimmer. 
6// Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby 
7// granted, provided that the above copyright notice and this permission notice appear in all copies. 
8// 
9// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL 
10// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, 
11// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN 
12// AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR 
13// PERFORMANCE OF THIS SOFTWARE. 
14 
15#include "Foundation/tMemory.h" 
16#include "Foundation/tAssert.h" 
17 
18 
19void* tMem::tMalloc(int size, int alignSize) 
20{ 
21 // This code works for both 32 and 64 bit pointers. 
22 bool isPow2 = ((alignSize < 1) || (alignSize & (alignSize-1))) ? false : true; 
23 tAssert(isPow2); 
24  
25 uint8* rawAddr = (uint8*)malloc(size + alignSize + sizeof(int)); 
26 if (!rawAddr) 
27 return nullptr; 
28 
29 uint8* base = rawAddr + sizeof(int); 
30 
31 // The align mask only works if alignSize is a power or 2. Essentially the '&' does a mod (%) and we find 
32 // an aligned address starting from base. 
33 int64 alignMask = alignSize - 1; 
34 uint8* alignedPtr = base + (alignSize - (int64(base) & alignMask)); 
35 
36 // We now need to write the offset in the 4 bytes before the aligned a 
37 base = alignedPtr - sizeof(int); 
38 *((int*)base) = int(alignedPtr - rawAddr); 
39 
40 return alignedPtr; 
41} 
42 
43 
44void tMem::tFree(void* mem) 
45{ 
46 uint8* rawAddr = (uint8*)mem; 
47 int* offsetAddr = ((int*)rawAddr) - 1; 
48 rawAddr -= *offsetAddr; 
49 free(rawAddr); 
50} 
51