From 1ddd3fbfe24d2b5a48281a17f67786e37608d75f Mon Sep 17 00:00:00 2001
From: Nameless <truemedian@gmail.com>
Date: Wed, 20 Nov 2024 07:14:55 -0600
Subject: [PATCH] fix: prevent calling uv.run while already running.

As documented, uv_run is NOT re-entrant and this
prevents this from happening by returning fail.

Each lua state has its own uv loop, so the only way
for this to happen is for uv.run to be called from
a libuv callback.
---
 src/loop.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/loop.c b/src/loop.c
index ffdb345d..f846ebd4 100644
--- a/src/loop.c
+++ b/src/loop.c
@@ -32,6 +32,11 @@ static const char *const luv_runmodes[] = {
 static int luv_run(lua_State* L) {
   int mode = luaL_checkoption(L, 1, "default", luv_runmodes);
   luv_ctx_t* ctx = luv_context(L);
+  if (ctx->mode != -1) {
+    lua_pushnil(L);
+    lua_pushstring(L, "loop already running");
+    return 2;
+  }
   ctx->mode = mode;
   int ret = uv_run(ctx->loop, (uv_run_mode)mode);
   ctx->mode = -1;