From 0f3cfad1e35b21e35564ef1476a956724942edb4 Mon Sep 17 00:00:00 2001
From: gltile-two-electric-boogaloo
 <80788438+gltile-two-electric-boogaloo@users.noreply.github.com>
Date: Sat, 21 May 2022 00:49:11 +0100
Subject: [PATCH] implement faster random number generation without segfaulting

---
 README.md   | 2 ++
 uwurandom.c | 9 +++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index be66e8b..89600fc 100644
--- a/README.md
+++ b/README.md
@@ -4,6 +4,8 @@
 [`/dev/uwurandom`](https://github.com/valadaptive/uwurandom) generates data through a tiny catgirl furiously typing away utter nonsense inside your computer.
 
 uwurandom-in-userspace does the same thing without the need to insert a kernel module.
+
+(uwurandom-in-userspace does not use a cryptographically secure random number generator.)
 ## Installation and usage
 
 ### Download uwurandom
diff --git a/uwurandom.c b/uwurandom.c
index 8ae8b62..64f9f6f 100644
--- a/uwurandom.c
+++ b/uwurandom.c
@@ -1310,7 +1310,8 @@ uint64_t rol64(uint64_t x, int k) {
     return (x << k) | (x >> (64 - k));
 }
 
-uint64_t xoshiro256ss(uint64_t s[4]) {
+uint64_t xoshiro256ss(uwu_state *state) {
+    uint64_t *s = state->rand_state;
     uint64_t const result = rol64(s[1] * 5, 7) * 9;
     uint64_t const t = s[1] << 17;
 
@@ -1328,9 +1329,9 @@ uint64_t xoshiro256ss(uint64_t s[4]) {
 static void get_random_buffered(uwu_state *state, void *dst, size_t size) {
     // TODO: handle cases where size is more than 8 bytes
 
-    if (size > (RAND_SIZE - state->rng_idx)) {
-        uint64_t rand = xoshiro256ss(state->rand_state);
-        state->rng_buf = (char*)rand;
+    if (size < (sizeof(uint64_t) - state->rng_idx)) {
+        uint64_t rand = xoshiro256ss(state);
+        *(state->rng_buf) = rand;
         state->rng_idx = 0;
     }
     memcpy(dst, state->rng_buf + state->rng_idx, size);