60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
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/* threadless.io
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* Copyright (c) 2016 Justin R. Cutler
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* Licensed under the MIT License. See LICENSE file in the project root for
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* full license information.
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*/
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/** @file
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* default allocator implementation
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* @author Justin R. Cutler <justin.r.cutler@gmail.com>
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*/
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/* errno, ENOMEM */
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#include <errno.h>
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/* realloc */
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#include <stdlib.h>
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/* ... */
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#include <threadless/allocator.h>
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#ifndef SIZE_MAX
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# define SIZE_MAX ((size_t)-1)
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#endif
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#define SQRT_SIZE_MAX_PLUS_1 ((size_t)1 << (sizeof(size_t) * 4))
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static void *default_allocate(allocator_t *allocator, void *ptr, size_t nmemb,
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size_t size)
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{
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/* ignore allocator */
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(void) allocator;
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/* test for multiplication overflow */
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if (((nmemb >= SQRT_SIZE_MAX_PLUS_1) || (size >= SQRT_SIZE_MAX_PLUS_1)) &&
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(nmemb != 0) && ((SIZE_MAX / nmemb) < size)) {
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/* overflow detected */
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errno = ENOMEM;
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return NULL;
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}
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/* perform allocator action */
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return realloc(ptr, size * nmemb);
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}
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static void default_destory(allocator_t *allocator)
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{
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/* ignore allocator */
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(void) allocator;
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}
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static allocator_t default_allocator = {
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.allocate = default_allocate,
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.destroy = default_destory,
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};
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allocator_t *allocator_get_default(void)
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{
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return &default_allocator;
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}
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