X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/15ef6053404686995024adb373854a009a3d2d39..42a6fcd6c59f7a51d0bda011e55e50960a28cfb5:/src/scripting.c

diff --git a/src/scripting.c b/src/scripting.c
index 0c18d916..99ca700c 100644
--- a/src/scripting.c
+++ b/src/scripting.c
@@ -180,6 +180,14 @@ int luaRedisCommand(lua_State *lua) {
         goto cleanup;
     }
 
+    if (cmd->flags & REDIS_CMD_WRITE && server.lua_random_dirty) {
+        luaPushError(lua,
+            "Write commands not allowed after non deterministic commands");
+        goto cleanup;
+    }
+
+    if (cmd->flags & REDIS_CMD_RANDOM) server.lua_random_dirty = 1;
+
     /* Run the command */
     cmd->proc(c);
 
@@ -257,9 +265,28 @@ void luaMaskCountHook(lua_State *lua, lua_Debug *ar) {
     }
 }
 
+void luaLoadLib(lua_State *lua, const char *libname, lua_CFunction luafunc) {
+  lua_pushcfunction(lua, luafunc);
+  lua_pushstring(lua, libname);
+  lua_call(lua, 1, 0);
+}
+
+void luaLoadLibraries(lua_State *lua) {
+    luaLoadLib(lua, "", luaopen_base);
+    luaLoadLib(lua, LUA_TABLIBNAME, luaopen_table);
+    luaLoadLib(lua, LUA_STRLIBNAME, luaopen_string);
+    luaLoadLib(lua, LUA_MATHLIBNAME, luaopen_math);
+    luaLoadLib(lua, LUA_DBLIBNAME, luaopen_debug); 
+
+#if 0 /* Stuff that we don't load currently, for sandboxing concerns. */
+    luaLoadLib(lua, LUA_LOADLIBNAME, luaopen_package);
+    luaLoadLib(lua, LUA_OSLIBNAME, luaopen_os);
+#endif
+}
+
 void scriptingInit(void) {
     lua_State *lua = lua_open();
-    luaL_openlibs(lua);
+    luaLoadLibraries(lua);
 
     /* Initialize a dictionary we use to map SHAs to scripts.
      * This is useful for replication, as we need to replicate EVALSHA
@@ -425,6 +452,16 @@ void evalGenericCommand(redisClient *c, int evalsha) {
      * not affected by external state. */
     redisSrand48(0);
 
+    /* We set this flag to zero to remember that so far no random command
+     * was called. This way we can allow the user to call commands like
+     * SRANDMEMBER or RANDOMKEY from Lua scripts as far as no write command
+     * is called (otherwise the replication and AOF would end with non
+     * deterministic sequences).
+     *
+     * Thanks to this flag we'll raise an error every time a write command
+     * is called after a random command was used. */
+    server.lua_random_dirty = 0;
+
     /* Get the number of arguments that are keys */
     if (getLongLongFromObjectOrReply(c,c->argv[2],&numkeys,NULL) != REDIS_OK)
         return;
@@ -494,7 +531,7 @@ void evalGenericCommand(redisClient *c, int evalsha) {
         {
             int retval = dictAdd(server.lua_scripts,
                                  sdsnewlen(funcname+2,40),c->argv[1]);
-            redisAssert(retval == DICT_OK);
+            redisAssertWithInfo(c,NULL,retval == DICT_OK);
             incrRefCount(c->argv[1]);
         }
     }
@@ -546,7 +583,7 @@ void evalGenericCommand(redisClient *c, int evalsha) {
     if (evalsha) {
         robj *script = dictFetchValue(server.lua_scripts,c->argv[1]->ptr);
 
-        redisAssert(script != NULL);
+        redisAssertWithInfo(c,NULL,script != NULL);
         rewriteClientCommandArgument(c,0,
             resetRefCount(createStringObject("EVAL",4)));
         rewriteClientCommandArgument(c,1,script);