From 4f210e15a07a4f00d4321f5fe17d9c0554c1019d Mon Sep 17 00:00:00 2001
From: Reece <me@reece.sx>
Date: Fri, 1 Oct 2021 18:22:59 +0100
Subject: [PATCH] [*] Made WELL_NextBytes atomic

---
 Source/RNG/WELL.cpp | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/Source/RNG/WELL.cpp b/Source/RNG/WELL.cpp
index b0ac7db9..5e238f06 100644
--- a/Source/RNG/WELL.cpp
+++ b/Source/RNG/WELL.cpp
@@ -58,11 +58,10 @@ WELLRand WELL_SeedRand64(AuUInt64 seed)
 /**
  * Generates a pseudo-randomly generated long.
  */
-AuUInt32 WELL_NextLong(WELLRand *rand)
+AuUInt32 WELL_NextLong_Unlocked(WELLRand *rand)
 {
     AuUInt32 a, b, c, d, ret;
 
-    rand->lock.Lock();
     a = rand->state[rand->index];
     c = rand->state[(rand->index + 13) & 15];
     b = a ^ c ^ (a << 16) ^ (c << 15);
@@ -74,6 +73,17 @@ AuUInt32 WELL_NextLong(WELLRand *rand)
     a = rand->state[rand->index];
     rand->state[rand->index] = a ^ b ^ d ^ (a << 2) ^ (b << 18) ^ (c << 28);
     ret = rand->state[rand->index];
+    return ret;
+}
+
+
+/**
+ * Generates a pseudo-randomly generated long.
+ */
+AuUInt32 WELL_NextLong(WELLRand *rand)
+{
+    rand->lock.Lock();
+    AuUInt32 ret = WELL_NextLong_Unlocked(rand);
     rand->lock.Unlock();
     return ret;
 }
@@ -85,17 +95,21 @@ void WELL_NextBytes(WELLRand *rand, void *in, AuUInt32 length)
 
     i    = 0;
     base = reinterpret_cast<AuUInt8 *>(in);
+    
+    rand->lock.Lock();
 
     for (; i < length; i += 4)
     {
-        AuUInt32 rng = WELL_NextLong(rand);
+        AuUInt32 rng = WELL_NextLong_Unlocked(rand);
         std::memcpy(base + i, &rng, 4);
     }
     
     if (i > length)
     {
         i -= 4;
-        AuUInt32 padRng = WELL_NextLong(rand);
+        AuUInt32 padRng = WELL_NextLong_Unlocked(rand);
         std::memcpy(base + i, &padRng, length - i);
     }
+    
+    rand->lock.Unlock();
 }
\ No newline at end of file