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sizecheck: add MALLOC_PERTURB_ support on non-Linux

develop
lethosor 2020-02-18 00:31:49 -05:00
parent fce52866c7
commit 0ec12657f4
1 changed files with 21 additions and 0 deletions
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21
depends/sizecheck/sizecheck.cpp
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@ -11,8 +11,22 @@
using namespace std;
const uint32_t MAGIC = 0xdfdf4ac8;
bool initialized = false;
int perturb = -1;
void init() {
#ifndef _LINUX
if (getenv("MALLOC_PERTURB_")) {
perturb = atoi(getenv("MALLOC_PERTURB_"));
}
#endif
initialized = true;
}
void* alloc(size_t n) {
if (!initialized) {
init();
}
void* addr;
if (posix_memalign(&addr, 32, n + 16) != 0) {
return addr;
@ -20,12 +34,19 @@ void* alloc(size_t n) {
memset(addr, 0, 16);
*(size_t*)addr = n;
*(uint32_t*)((uint8_t*)addr + 8) = MAGIC;
if (perturb > 0) {
memset((uint8_t*)addr + 16, ~(perturb & 0xff), n);
}
return (uint8_t*)addr + 16;
}
void dealloc(void* addr) {
if (!initialized) {
init();
}
if (uintptr_t(addr) % 32 == 16 && *(uint32_t*)((uint8_t*)addr - 8) == MAGIC) {
addr = (void*)((uint8_t*)addr - 16);
memset((uint8_t*)addr + 16, perturb & 0xff, *(size_t*)addr);
}
free(addr);
}