1//===-- sanitizer_allocator_dlsym.h -----------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Hack: Sanitizer initializer calls dlsym which may need to allocate and call
10// back into uninitialized sanitizer.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef SANITIZER_ALLOCATOR_DLSYM_H
15#define SANITIZER_ALLOCATOR_DLSYM_H
16
17#include "sanitizer_allocator_internal.h"
18
19namespace __sanitizer {
20
21template <typename Details>
22struct DlSymAllocator {
23 static bool Use() {
24 // Fuchsia doesn't use dlsym-based interceptors.
25 return !SANITIZER_FUCHSIA && UNLIKELY(Details::UseImpl());
26 }
27
28 static bool PointerIsMine(const void *ptr) {
29 // Fuchsia doesn't use dlsym-based interceptors.
30 return !SANITIZER_FUCHSIA &&
31 UNLIKELY(internal_allocator()->FromPrimary(ptr));
32 }
33
34 static void *Allocate(uptr size_in_bytes) {
35 void *ptr = InternalAlloc(size: size_in_bytes, cache: nullptr, alignment: kWordSize);
36 CHECK(internal_allocator()->FromPrimary(ptr));
37 Details::OnAllocate(ptr,
38 internal_allocator()->GetActuallyAllocatedSize(p: ptr));
39 return ptr;
40 }
41
42 static void *Callocate(SIZE_T nmemb, SIZE_T size) {
43 void *ptr = InternalCalloc(count: nmemb, size);
44 CHECK(internal_allocator()->FromPrimary(ptr));
45 Details::OnAllocate(ptr,
46 internal_allocator()->GetActuallyAllocatedSize(p: ptr));
47 return ptr;
48 }
49
50 static void Free(void *ptr) {
51 uptr size = internal_allocator()->GetActuallyAllocatedSize(p: ptr);
52 Details::OnFree(ptr, size);
53 InternalFree(p: ptr);
54 }
55
56 static void *Realloc(void *ptr, uptr new_size) {
57 if (!ptr)
58 return Allocate(size_in_bytes: new_size);
59 CHECK(internal_allocator()->FromPrimary(ptr));
60 if (!new_size) {
61 Free(ptr);
62 return nullptr;
63 }
64 uptr size = internal_allocator()->GetActuallyAllocatedSize(p: ptr);
65 uptr memcpy_size = Min(a: new_size, b: size);
66 void *new_ptr = Allocate(size_in_bytes: new_size);
67 if (new_ptr)
68 internal_memcpy(dest: new_ptr, src: ptr, n: memcpy_size);
69 Free(ptr);
70 return new_ptr;
71 }
72
73 static void OnAllocate(const void *ptr, uptr size) {}
74 static void OnFree(const void *ptr, uptr size) {}
75};
76
77} // namespace __sanitizer
78
79#endif // SANITIZER_ALLOCATOR_DLSYM_H
80

source code of compiler-rt/lib/sanitizer_common/sanitizer_allocator_dlsym.h