From ce4bacdaff26f7eb5bff58c3bc5be6a1742a60d4 Mon Sep 17 00:00:00 2001
From: PragmaTwice <twice.mliu@gmail.com>
Date: Fri, 10 Mar 2023 23:06:47 +0800
Subject: [PATCH] fix script exists

---
 src/server/server.cc     | 7 +++++++
 src/storage/scripting.cc | 4 ++--
 src/storage/scripting.h  | 2 ++
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/server/server.cc b/src/server/server.cc
index d2d8209d9e1..55ee5303f46 100644
--- a/src/server/server.cc
+++ b/src/server/server.cc
@@ -36,6 +36,7 @@
 #include "commands/commander.h"
 #include "config.h"
 #include "fmt/format.h"
+#include "lua.h"
 #include "redis_connection.h"
 #include "redis_request.h"
 #include "storage/compaction_checker.h"
@@ -1498,6 +1499,12 @@ Status Server::LookupAndCreateCommand(const std::string &cmd_name, std::unique_p
 }
 
 Status Server::ScriptExists(const std::string &sha) {
+  lua_getglobal(lua_, (REDIS_LUA_FUNC_SHA_PREFIX + sha).c_str());
+  if (!lua_isnil(lua_, -1)) {
+    return Status::OK();
+  }
+  lua_pop(lua_, 1);
+
   std::string body;
   return ScriptGet(sha, &body);
 }
diff --git a/src/storage/scripting.cc b/src/storage/scripting.cc
index 17fc23012dc..e1aa723364c 100644
--- a/src/storage/scripting.cc
+++ b/src/storage/scripting.cc
@@ -220,7 +220,7 @@ Status evalGenericCommand(Redis::Connection *conn, const std::vector<std::string
 
   /* We obtain the script SHA1, then check if this function is already
    * defined into the Lua state */
-  char funcname[2 + 40 + 1] = "f_";
+  char funcname[2 + 40 + 1] = REDIS_LUA_FUNC_SHA_PREFIX;
 
   if (!evalsha) {
     SHA1Hex(funcname + 2, args[1].c_str(), args[1].size());
@@ -873,7 +873,7 @@ int redisMathRandomSeed(lua_State *L) {
  * If 'c' is not NULL, on error the client is informed with an appropriate
  * error describing the nature of the problem and the Lua interpreter error. */
 Status createFunction(Server *srv, const std::string &body, std::string *sha, lua_State *lua, bool need_to_store) {
-  char funcname[2 + 40 + 1] = "f_";
+  char funcname[2 + 40 + 1] = REDIS_LUA_FUNC_SHA_PREFIX;
 
   SHA1Hex(funcname + 2, body.c_str(), body.size());
   *sha = funcname + 2;
diff --git a/src/storage/scripting.h b/src/storage/scripting.h
index fbe063221ae..eb2ed2ccc30 100644
--- a/src/storage/scripting.h
+++ b/src/storage/scripting.h
@@ -27,6 +27,8 @@
 #include "server/redis_connection.h"
 #include "status.h"
 
+#define REDIS_LUA_FUNC_SHA_PREFIX "f_"  // NOLINT
+
 namespace Lua {
 
 lua_State *CreateState(bool read_only = false);