| //===-- sanitizer_allocator.cc --------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is shared between AddressSanitizer and ThreadSanitizer |
| // run-time libraries. |
| // This allocator that is used inside run-times. |
| //===----------------------------------------------------------------------===// |
| #include "sanitizer_common.h" |
| |
| // FIXME: We should probably use more low-level allocator that would |
| // mmap some pages and split them into chunks to fulfill requests. |
| #ifdef __linux__ |
| extern "C" void *__libc_malloc(__sanitizer::uptr size); |
| extern "C" void __libc_free(void *ptr); |
| # define LIBC_MALLOC __libc_malloc |
| # define LIBC_FREE __libc_free |
| #else // __linux__ |
| # include <stdlib.h> |
| # define LIBC_MALLOC malloc |
| # define LIBC_FREE free |
| #endif // __linux__ |
| |
| namespace __sanitizer { |
| |
| const u64 kBlockMagic = 0x6A6CB03ABCEBC041ull; |
| |
| void *InternalAlloc(uptr size) { |
| if (size + sizeof(u64) < size) |
| return 0; |
| void *p = LIBC_MALLOC(size + sizeof(u64)); |
| if (p == 0) |
| return 0; |
| ((u64*)p)[0] = kBlockMagic; |
| return (char*)p + sizeof(u64); |
| } |
| |
| void InternalFree(void *addr) { |
| if (addr == 0) |
| return; |
| addr = (char*)addr - sizeof(u64); |
| CHECK_EQ(((u64*)addr)[0], kBlockMagic); |
| ((u64*)addr)[0] = 0; |
| LIBC_FREE(addr); |
| } |
| |
| void *InternalAllocBlock(void *p) { |
| CHECK_NE(p, (void*)0); |
| u64 *pp = (u64*)((uptr)p & ~0x7); |
| for (; pp[0] != kBlockMagic; pp--) {} |
| return pp + 1; |
| } |
| |
| } // namespace __sanitizer |