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-rw-r--r--deps/v8/src/v8.cc44
1 files changed, 17 insertions, 27 deletions
diff --git a/deps/v8/src/v8.cc b/deps/v8/src/v8.cc
index 0b562fc28..11af057b1 100644
--- a/deps/v8/src/v8.cc
+++ b/deps/v8/src/v8.cc
@@ -100,42 +100,34 @@ void V8::TearDown() {
}
-static uint32_t random_seed() {
- if (FLAG_random_seed == 0) {
- return random();
+static void seed_random(uint32_t* state) {
+ for (int i = 0; i < 2; ++i) {
+ state[i] = FLAG_random_seed;
+ while (state[i] == 0) {
+ state[i] = random();
+ }
}
- return FLAG_random_seed;
}
-typedef struct {
- uint32_t hi;
- uint32_t lo;
-} random_state;
+// Random number generator using George Marsaglia's MWC algorithm.
+static uint32_t random_base(uint32_t* state) {
+ // Initialize seed using the system random().
+ // No non-zero seed will ever become zero again.
+ if (state[0] == 0) seed_random(state);
+ // Mix the bits. Never replaces state[i] with 0 if it is nonzero.
+ state[0] = 18273 * (state[0] & 0xFFFF) + (state[0] >> 16);
+ state[1] = 36969 * (state[1] & 0xFFFF) + (state[1] >> 16);
-// Random number generator using George Marsaglia's MWC algorithm.
-static uint32_t random_base(random_state *state) {
- // Initialize seed using the system random(). If one of the seeds
- // should ever become zero again, or if random() returns zero, we
- // avoid getting stuck with zero bits in hi or lo by re-initializing
- // them on demand.
- if (state->hi == 0) state->hi = random_seed();
- if (state->lo == 0) state->lo = random_seed();
-
- // Mix the bits.
- state->hi = 36969 * (state->hi & 0xFFFF) + (state->hi >> 16);
- state->lo = 18273 * (state->lo & 0xFFFF) + (state->lo >> 16);
- return (state->hi << 16) + (state->lo & 0xFFFF);
+ return (state[0] << 14) + (state[1] & 0x3FFFF);
}
// Used by JavaScript APIs
uint32_t V8::Random(Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
- // TODO(isolates): move lo and hi to isolate
- static random_state state = {0, 0};
- return random_base(&state);
+ return random_base(isolate->random_seed());
}
@@ -144,9 +136,7 @@ uint32_t V8::Random(Isolate* isolate) {
// leaks that could be used in an exploit.
uint32_t V8::RandomPrivate(Isolate* isolate) {
ASSERT(isolate == Isolate::Current());
- // TODO(isolates): move lo and hi to isolate
- static random_state state = {0, 0};
- return random_base(&state);
+ return random_base(isolate->private_random_seed());
}