1 | /* |
2 | * Copyright (c) 2006-2009 Erin Catto http://www.box2d.org |
3 | * |
4 | * This software is provided 'as-is', without any express or implied |
5 | * warranty. In no event will the authors be held liable for any damages |
6 | * arising from the use of this software. |
7 | * Permission is granted to anyone to use this software for any purpose, |
8 | * including commercial applications, and to alter it and redistribute it |
9 | * freely, subject to the following restrictions: |
10 | * 1. The origin of this software must not be misrepresented; you must not |
11 | * claim that you wrote the original software. If you use this software |
12 | * in a product, an acknowledgment in the product documentation would be |
13 | * appreciated but is not required. |
14 | * 2. Altered source versions must be plainly marked as such, and must not be |
15 | * misrepresented as being the original software. |
16 | * 3. This notice may not be removed or altered from any source distribution. |
17 | */ |
18 | |
19 | #ifndef B2_STACK_ALLOCATOR_H |
20 | #define B2_STACK_ALLOCATOR_H |
21 | |
22 | #include <Box2D/Common/b2Settings.h> |
23 | |
24 | const int32 b2_stackSize = 100 * 1024; // 100k |
25 | const int32 b2_maxStackEntries = 32; |
26 | |
27 | struct b2StackEntry |
28 | { |
29 | char* data; |
30 | int32 size; |
31 | bool usedMalloc; |
32 | }; |
33 | |
34 | // This is a stack allocator used for fast per step allocations. |
35 | // You must nest allocate/free pairs. The code will assert |
36 | // if you try to interleave multiple allocate/free pairs. |
37 | class b2StackAllocator |
38 | { |
39 | public: |
40 | b2StackAllocator(); |
41 | ~b2StackAllocator(); |
42 | |
43 | void* Allocate(int32 size); |
44 | void Free(void* p); |
45 | |
46 | int32 GetMaxAllocation() const; |
47 | |
48 | private: |
49 | |
50 | char m_data[b2_stackSize]; |
51 | int32 m_index; |
52 | |
53 | int32 m_allocation; |
54 | int32 m_maxAllocation; |
55 | |
56 | b2StackEntry m_entries[b2_maxStackEntries]; |
57 | int32 m_entryCount; |
58 | }; |
59 | |
60 | #endif |
61 | |