| /* |
| * Copyright 2009 Nicolai Hähnle <nhaehnle@gmail.com> |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * on the rights to use, copy, modify, merge, publish, distribute, sub |
| * license, and/or sell copies of the Software, and to permit persons to whom |
| * the Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM, |
| * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
| * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
| * USE OR OTHER DEALINGS IN THE SOFTWARE. */ |
| |
| #ifndef MEMORY_POOL_H |
| #define MEMORY_POOL_H |
| |
| struct memory_block; |
| |
| /** |
| * Provides a pool of memory that can quickly be allocated from, at the |
| * cost of being unable to explicitly free one of the allocated blocks. |
| * Instead, the entire pool can be freed at once. |
| * |
| * The idea is to allow one to quickly allocate a flexible amount of |
| * memory during operations like shader compilation while avoiding |
| * reference counting headaches. |
| */ |
| struct memory_pool { |
| unsigned char * head; |
| unsigned char * end; |
| unsigned int total_allocated; |
| struct memory_block * blocks; |
| }; |
| |
| |
| void memory_pool_init(struct memory_pool * pool); |
| void memory_pool_destroy(struct memory_pool * pool); |
| void * memory_pool_malloc(struct memory_pool * pool, unsigned int bytes); |
| |
| |
| /** |
| * Generic helper for growing an array that has separate size/count |
| * and reserved counters to accomodate up to num new element. |
| * |
| * type * Array; |
| * unsigned int Size; |
| * unsigned int Reserved; |
| * |
| * memory_pool_array_reserve(pool, type, Array, Size, Reserved, k); |
| * assert(Size + k < Reserved); |
| * |
| * \note Size is not changed by this macro. |
| * |
| * \warning Array, Size, Reserved have to be lvalues and may be evaluated |
| * several times. |
| */ |
| #define memory_pool_array_reserve(pool, type, array, size, reserved, num) do { \ |
| unsigned int _num = (num); \ |
| if ((size) + _num > (reserved)) { \ |
| unsigned int newreserve = (reserved) * 2; \ |
| type * newarray; \ |
| if (newreserve < _num) \ |
| newreserve = 4 * _num; /* arbitrary heuristic */ \ |
| newarray = memory_pool_malloc((pool), newreserve * sizeof(type)); \ |
| memcpy(newarray, (array), (size) * sizeof(type)); \ |
| (array) = newarray; \ |
| (reserved) = newreserve; \ |
| } \ |
| } while(0) |
| |
| #endif /* MEMORY_POOL_H */ |