| /* |
| * Copyright (c) 2007 Intel Corporation. All Rights Reserved. |
| * |
| * 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 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 PRECISION INSIGHT AND/OR ITS 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. |
| */ |
| |
| #include <stdlib.h> |
| #include <assert.h> |
| #include "object_heap.h" |
| |
| #define ASSERT assert |
| |
| #define LAST_FREE -1 |
| #define ALLOCATED -2 |
| |
| /* |
| * Expands the heap |
| * Return 0 on success, -1 on error |
| */ |
| static int |
| object_heap_expand(object_heap_p heap) |
| { |
| int i; |
| void *new_heap_index; |
| int next_free; |
| int new_heap_size = heap->heap_size + heap->heap_increment; |
| int bucket_index = new_heap_size / heap->heap_increment - 1; |
| |
| if (bucket_index >= heap->num_buckets) { |
| int new_num_buckets = heap->num_buckets + 8; |
| void **new_bucket; |
| |
| new_bucket = realloc(heap->bucket, new_num_buckets * sizeof(void *)); |
| if (NULL == new_bucket) { |
| return -1; |
| } |
| |
| heap->num_buckets = new_num_buckets; |
| heap->bucket = new_bucket; |
| } |
| |
| new_heap_index = (void *) malloc(heap->heap_increment * heap->object_size); |
| if (NULL == new_heap_index) { |
| return -1; /* Out of memory */ |
| } |
| |
| heap->bucket[bucket_index] = new_heap_index; |
| next_free = heap->next_free; |
| for (i = new_heap_size; i-- > heap->heap_size;) { |
| object_base_p obj = (object_base_p)(new_heap_index + (i - heap->heap_size) * heap->object_size); |
| obj->id = i + heap->id_offset; |
| obj->next_free = next_free; |
| next_free = i; |
| } |
| heap->next_free = next_free; |
| heap->heap_size = new_heap_size; |
| return 0; /* Success */ |
| } |
| |
| /* |
| * Return 0 on success, -1 on error |
| */ |
| int |
| object_heap_init(object_heap_p heap, int object_size, int id_offset) |
| { |
| pthread_mutex_init(&heap->mutex, NULL); |
| heap->object_size = object_size; |
| heap->id_offset = id_offset & OBJECT_HEAP_OFFSET_MASK; |
| heap->heap_size = 0; |
| heap->heap_increment = 16; |
| heap->next_free = LAST_FREE; |
| heap->num_buckets = 0; |
| heap->bucket = NULL; |
| return object_heap_expand(heap); |
| } |
| |
| /* |
| * Allocates an object |
| * Returns the object ID on success, returns -1 on error |
| */ |
| static int |
| object_heap_allocate_unlocked(object_heap_p heap) |
| { |
| object_base_p obj; |
| int bucket_index, obj_index; |
| |
| if (LAST_FREE == heap->next_free) { |
| if (-1 == object_heap_expand(heap)) { |
| return -1; /* Out of memory */ |
| } |
| } |
| ASSERT(heap->next_free >= 0); |
| |
| bucket_index = heap->next_free / heap->heap_increment; |
| obj_index = heap->next_free % heap->heap_increment; |
| |
| obj = (object_base_p)(heap->bucket[bucket_index] + obj_index * heap->object_size); |
| heap->next_free = obj->next_free; |
| obj->next_free = ALLOCATED; |
| return obj->id; |
| } |
| |
| int |
| object_heap_allocate(object_heap_p heap) |
| { |
| int ret; |
| |
| pthread_mutex_lock(&heap->mutex); |
| ret = object_heap_allocate_unlocked(heap); |
| pthread_mutex_unlock(&heap->mutex); |
| return ret; |
| } |
| |
| /* |
| * Lookup an object by object ID |
| * Returns a pointer to the object on success, returns NULL on error |
| */ |
| static object_base_p |
| object_heap_lookup_unlocked(object_heap_p heap, int id) |
| { |
| object_base_p obj; |
| int bucket_index, obj_index; |
| |
| if ((id < heap->id_offset) || (id > (heap->heap_size + heap->id_offset))) { |
| return NULL; |
| } |
| id &= OBJECT_HEAP_ID_MASK; |
| bucket_index = id / heap->heap_increment; |
| obj_index = id % heap->heap_increment; |
| obj = (object_base_p)(heap->bucket[bucket_index] + obj_index * heap->object_size); |
| |
| /* Check if the object has in fact been allocated */ |
| if (obj->next_free != ALLOCATED) { |
| return NULL; |
| } |
| return obj; |
| } |
| |
| object_base_p |
| object_heap_lookup(object_heap_p heap, int id) |
| { |
| object_base_p obj; |
| |
| pthread_mutex_lock(&heap->mutex); |
| obj = object_heap_lookup_unlocked(heap, id); |
| pthread_mutex_unlock(&heap->mutex); |
| return obj; |
| } |
| |
| /* |
| * Iterate over all objects in the heap. |
| * Returns a pointer to the first object on the heap, returns NULL if heap is empty. |
| */ |
| object_base_p |
| object_heap_first(object_heap_p heap, object_heap_iterator *iter) |
| { |
| *iter = -1; |
| return object_heap_next(heap, iter); |
| } |
| |
| /* |
| * Iterate over all objects in the heap. |
| * Returns a pointer to the next object on the heap, returns NULL if heap is empty. |
| */ |
| static object_base_p |
| object_heap_next_unlocked(object_heap_p heap, object_heap_iterator *iter) |
| { |
| object_base_p obj; |
| int bucket_index, obj_index; |
| int i = *iter + 1; |
| |
| while (i < heap->heap_size) { |
| bucket_index = i / heap->heap_increment; |
| obj_index = i % heap->heap_increment; |
| |
| obj = (object_base_p)(heap->bucket[bucket_index] + obj_index * heap->object_size); |
| if (obj->next_free == ALLOCATED) { |
| *iter = i; |
| return obj; |
| } |
| i++; |
| } |
| *iter = i; |
| return NULL; |
| } |
| |
| object_base_p |
| object_heap_next(object_heap_p heap, object_heap_iterator *iter) |
| { |
| object_base_p obj; |
| |
| pthread_mutex_lock(&heap->mutex); |
| obj = object_heap_next_unlocked(heap, iter); |
| pthread_mutex_unlock(&heap->mutex); |
| return obj; |
| } |
| |
| /* |
| * Frees an object |
| */ |
| static void |
| object_heap_free_unlocked(object_heap_p heap, object_base_p obj) |
| { |
| /* Check if the object has in fact been allocated */ |
| ASSERT(obj->next_free == ALLOCATED); |
| |
| obj->next_free = heap->next_free; |
| heap->next_free = obj->id & OBJECT_HEAP_ID_MASK; |
| } |
| |
| void |
| object_heap_free(object_heap_p heap, object_base_p obj) |
| { |
| if (!obj) |
| return; |
| pthread_mutex_lock(&heap->mutex); |
| object_heap_free_unlocked(heap, obj); |
| pthread_mutex_unlock(&heap->mutex); |
| } |
| |
| /* |
| * Destroys a heap, the heap must be empty. |
| */ |
| void |
| object_heap_destroy(object_heap_p heap) |
| { |
| object_base_p obj; |
| int bucket_index, obj_index, i; |
| |
| /* Check if heap is empty */ |
| for (i = 0; i < heap->heap_size; i++) { |
| /* Check if object is not still allocated */ |
| bucket_index = i / heap->heap_increment; |
| obj_index = i % heap->heap_increment; |
| obj = (object_base_p)(heap->bucket[bucket_index] + obj_index * heap->object_size); |
| ASSERT(obj->next_free != ALLOCATED); |
| } |
| |
| for (i = 0; i < heap->heap_size / heap->heap_increment; i++) { |
| free(heap->bucket[i]); |
| } |
| |
| pthread_mutex_destroy(&heap->mutex); |
| |
| free(heap->bucket); |
| heap->bucket = NULL; |
| heap->heap_size = 0; |
| heap->next_free = LAST_FREE; |
| } |