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merge from dev-atomic

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This commit is contained in:
daan 2020-09-03 09:47:01 -07:00
commit 900c97664a
18 changed files with 391 additions and 398 deletions
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31
src/random.c
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@ -162,20 +162,29 @@ If we cannot get good randomness, we fall back to weak randomness based on a tim
-----------------------------------------------------------------------------*/
#if defined(_WIN32)
/*
// We prefer BCryptGenRandom over RtlGenRandom but it leads to a crash a when using dynamic override combined with the C++ runtime :-(
#pragma comment (lib,"bcrypt.lib")
#include <bcrypt.h>
static bool os_random_buf(void* buf, size_t buf_len) {
return (BCryptGenRandom(NULL, (PUCHAR)buf, (ULONG)buf_len, BCRYPT_USE_SYSTEM_PREFERRED_RNG) >= 0);
}
/*
#define SystemFunction036 NTAPI SystemFunction036
#include <NTSecAPI.h>
#undef SystemFunction036
static bool os_random_buf(void* buf, size_t buf_len) {
RtlGenRandom(buf, (ULONG)buf_len);
return true;
}
*/
#define RtlGenRandom SystemFunction036
#ifdef __cplusplus
extern "C" {
#endif
BOOLEAN NTAPI RtlGenRandom(PVOID RandomBuffer, ULONG RandomBufferLength);
#ifdef __cplusplus
}
#endif
static bool os_random_buf(void* buf, size_t buf_len) {
mi_assert_internal(buf_len >= sizeof(uintptr_t));
memset(buf, 0, buf_len);
RtlGenRandom(buf, (ULONG)buf_len);
return (((uintptr_t*)buf)[0] != 0); // sanity check (but RtlGenRandom should never fail)
}
#elif defined(ANDROID) || defined(XP_DARWIN) || defined(__APPLE__) || defined(__DragonFly__) || \
defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) || \
defined(__sun) || defined(__wasi__)
@ -200,12 +209,12 @@ static bool os_random_buf(void* buf, size_t buf_len) {
#ifndef GRND_NONBLOCK
#define GRND_NONBLOCK (1)
#endif
static volatile _Atomic(uintptr_t) no_getrandom; // = 0
if (mi_atomic_read(&no_getrandom)==0) {
static _Atomic(uintptr_t) no_getrandom; // = 0
if (mi_atomic_load_acquire(&no_getrandom)==0) {
ssize_t ret = syscall(SYS_getrandom, buf, buf_len, GRND_NONBLOCK);
if (ret >= 0) return (buf_len == (size_t)ret);
if (ret != ENOSYS) return false;
mi_atomic_write(&no_getrandom,1); // don't call again, and fall back to /dev/urandom
mi_atomic_store_release(&no_getrandom,1); // don't call again, and fall back to /dev/urandom
}
#endif
int flags = O_RDONLY;