1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "base/allocator/allocator_shim.h"
6
7 #include <malloc.h>
8
9 // This translation unit defines a default dispatch for the allocator shim which
10 // routes allocations to libc functions.
11 // The code here is strongly inspired from tcmalloc's libc_override_glibc.h.
12
13 extern "C" {
14 void* __libc_malloc(size_t size);
15 void* __libc_calloc(size_t n, size_t size);
16 void* __libc_realloc(void* address, size_t size);
17 void* __libc_memalign(size_t alignment, size_t size);
18 void __libc_free(void* ptr);
19 } // extern "C"
20
21 namespace {
22
23 using base::allocator::AllocatorDispatch;
24
GlibcMalloc(const AllocatorDispatch *,size_t size,void * context)25 void* GlibcMalloc(const AllocatorDispatch*, size_t size, void* context) {
26 return __libc_malloc(size);
27 }
28
GlibcCalloc(const AllocatorDispatch *,size_t n,size_t size,void * context)29 void* GlibcCalloc(const AllocatorDispatch*,
30 size_t n,
31 size_t size,
32 void* context) {
33 return __libc_calloc(n, size);
34 }
35
GlibcRealloc(const AllocatorDispatch *,void * address,size_t size,void * context)36 void* GlibcRealloc(const AllocatorDispatch*,
37 void* address,
38 size_t size,
39 void* context) {
40 return __libc_realloc(address, size);
41 }
42
GlibcMemalign(const AllocatorDispatch *,size_t alignment,size_t size,void * context)43 void* GlibcMemalign(const AllocatorDispatch*,
44 size_t alignment,
45 size_t size,
46 void* context) {
47 return __libc_memalign(alignment, size);
48 }
49
GlibcFree(const AllocatorDispatch *,void * address,void * context)50 void GlibcFree(const AllocatorDispatch*, void* address, void* context) {
51 __libc_free(address);
52 }
53
GlibcGetSizeEstimate(const AllocatorDispatch *,void * address,void * context)54 size_t GlibcGetSizeEstimate(const AllocatorDispatch*,
55 void* address,
56 void* context) {
57 // TODO(siggi, primiano): malloc_usable_size may need redirection in the
58 // presence of interposing shims that divert allocations.
59 return malloc_usable_size(address);
60 }
61
62 } // namespace
63
64 const AllocatorDispatch AllocatorDispatch::default_dispatch = {
65 &GlibcMalloc, /* alloc_function */
66 &GlibcCalloc, /* alloc_zero_initialized_function */
67 &GlibcMemalign, /* alloc_aligned_function */
68 &GlibcRealloc, /* realloc_function */
69 &GlibcFree, /* free_function */
70 &GlibcGetSizeEstimate, /* get_size_estimate_function */
71 nullptr, /* batch_malloc_function */
72 nullptr, /* batch_free_function */
73 nullptr, /* free_definite_size_function */
74 nullptr, /* next */
75 };
76