/src/aom/aom_mem/aom_mem.c
Line | Count | Source |
1 | | /* |
2 | | * Copyright (c) 2016, Alliance for Open Media. All rights reserved. |
3 | | * |
4 | | * This source code is subject to the terms of the BSD 2 Clause License and |
5 | | * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License |
6 | | * was not distributed with this source code in the LICENSE file, you can |
7 | | * obtain it at www.aomedia.org/license/software. If the Alliance for Open |
8 | | * Media Patent License 1.0 was not distributed with this source code in the |
9 | | * PATENTS file, you can obtain it at www.aomedia.org/license/patent. |
10 | | */ |
11 | | |
12 | | #include "aom_mem.h" |
13 | | #include <assert.h> |
14 | | #include <stdlib.h> |
15 | | #include <string.h> |
16 | | #include "include/aom_mem_intrnl.h" |
17 | | #include "aom/aom_integer.h" |
18 | | |
19 | 8.20M | static size_t GetAllocationPaddingSize(size_t align) { |
20 | 8.20M | assert(align > 0); |
21 | 8.20M | assert(align < SIZE_MAX - ADDRESS_STORAGE_SIZE); |
22 | 8.20M | return align - 1 + ADDRESS_STORAGE_SIZE; |
23 | 8.20M | } |
24 | | |
25 | | // Returns 0 in case of overflow of nmemb * size. |
26 | | static int check_size_argument_overflow(size_t nmemb, size_t size, |
27 | 4.54M | size_t align) { |
28 | 4.54M | if (nmemb == 0) return 1; |
29 | 4.53M | const size_t alloc_padding = GetAllocationPaddingSize(align); |
30 | 4.53M | #if defined(AOM_MAX_ALLOCABLE_MEMORY) |
31 | 4.53M | assert(AOM_MAX_ALLOCABLE_MEMORY >= alloc_padding); |
32 | 4.53M | assert(AOM_MAX_ALLOCABLE_MEMORY <= SIZE_MAX); |
33 | 4.53M | if (size > (AOM_MAX_ALLOCABLE_MEMORY - alloc_padding) / nmemb) return 0; |
34 | | #else |
35 | | if (size > (SIZE_MAX - alloc_padding) / nmemb) return 0; |
36 | | #endif |
37 | 4.53M | return 1; |
38 | 4.53M | } |
39 | | |
40 | 7.34M | static size_t *GetMallocAddressLocation(void *const mem) { |
41 | 7.34M | return ((size_t *)mem) - 1; |
42 | 7.34M | } |
43 | | |
44 | | static void SetActualMallocAddress(void *const mem, |
45 | 3.67M | const void *const malloc_addr) { |
46 | 3.67M | size_t *const malloc_addr_location = GetMallocAddressLocation(mem); |
47 | 3.67M | *malloc_addr_location = (size_t)malloc_addr; |
48 | 3.67M | } |
49 | | |
50 | 3.67M | static void *GetActualMallocAddress(void *const mem) { |
51 | 3.67M | const size_t *const malloc_addr_location = GetMallocAddressLocation(mem); |
52 | 3.67M | return (void *)(*malloc_addr_location); |
53 | 3.67M | } |
54 | | |
55 | 3.67M | void *aom_memalign(size_t align, size_t size) { |
56 | 3.67M | void *x = NULL; |
57 | 3.67M | if (!check_size_argument_overflow(1, size, align)) return NULL; |
58 | 3.67M | const size_t aligned_size = size + GetAllocationPaddingSize(align); |
59 | 3.67M | void *const addr = malloc(aligned_size); |
60 | 3.67M | if (addr) { |
61 | 3.67M | x = aom_align_addr((unsigned char *)addr + ADDRESS_STORAGE_SIZE, align); |
62 | 3.67M | SetActualMallocAddress(x, addr); |
63 | 3.67M | } |
64 | 3.67M | return x; |
65 | 3.67M | } |
66 | | |
67 | 1.60M | void *aom_malloc(size_t size) { return aom_memalign(DEFAULT_ALIGNMENT, size); } |
68 | | |
69 | 870k | void *aom_calloc(size_t num, size_t size) { |
70 | 870k | if (!check_size_argument_overflow(num, size, DEFAULT_ALIGNMENT)) return NULL; |
71 | 869k | const size_t total_size = num * size; |
72 | 869k | void *const x = aom_malloc(total_size); |
73 | 869k | if (x) memset(x, 0, total_size); |
74 | 869k | return x; |
75 | 870k | } |
76 | | |
77 | 6.00M | void aom_free(void *memblk) { |
78 | 6.00M | if (memblk) { |
79 | 3.67M | void *addr = GetActualMallocAddress(memblk); |
80 | 3.67M | free(addr); |
81 | 3.67M | } |
82 | 6.00M | } |