X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/794e6ce14ff85f00b0d3e86365e9cc45a90d3bcf..188a17ed563ef59bffa8b47b365079f264859b90:/src/scripting.c

diff --git a/src/scripting.c b/src/scripting.c
index 1503c3c9..e38d0807 100644
--- a/src/scripting.c
+++ b/src/scripting.c
@@ -27,7 +27,7 @@ int redis_math_randomseed (lua_State *L);
  * is like a normal client that bypasses all the slow I/O paths.
  *
  * Note: in this function we do not do any sanity check as the reply is
- * generated by Redis directly. This allows use to go faster.
+ * generated by Redis directly. This allows us to go faster.
  * The reply string can be altered during the parsing as it is discared
  * after the conversion is completed.
  *
@@ -128,6 +128,37 @@ void luaPushError(lua_State *lua, char *error) {
     lua_settable(lua,-3);
 }
 
+/* Sort the array currently in the stack. We do this to make the output
+ * of commands like KEYS or SMEMBERS something deterministic when called
+ * from Lua (to play well with AOf/replication).
+ *
+ * The array is sorted using table.sort itself, and assuming all the
+ * list elements are strings. */
+void luaSortArray(lua_State *lua) {
+    /* Initial Stack: array */
+    lua_getglobal(lua,"table");
+    lua_pushstring(lua,"sort");
+    lua_gettable(lua,-2);       /* Stack: array, table, table.sort */
+    lua_pushvalue(lua,-3);      /* Stack: array, table, table.sort, array */
+    if (lua_pcall(lua,1,0,0)) {
+        /* Stack: array, table, error */
+
+        /* We are not interested in the error, we assume that the problem is
+         * that there are 'false' elements inside the array, so we try
+         * again with a slower function but able to handle this case, that
+         * is: table.sort(table, __redis__compare_helper) */
+        lua_pop(lua,1);             /* Stack: array, table */
+        lua_pushstring(lua,"sort"); /* Stack: array, table, sort */
+        lua_gettable(lua,-2);       /* Stack: array, table, table.sort */
+        lua_pushvalue(lua,-3);      /* Stack: array, table, table.sort, array */
+        lua_getglobal(lua,"__redis__compare_helper");
+        /* Stack: array, table, table.sort, array, __redis__compare_helper */
+        lua_call(lua,2,0);
+    }
+    /* Stack: array (sorted), table */
+    lua_pop(lua,1);             /* Stack: array (sorted) */
+}
+
 int luaRedisGenericCommand(lua_State *lua, int raise_error) {
     int j, argc = lua_gettop(lua);
     struct redisCommand *cmd;
@@ -175,22 +206,53 @@ int luaRedisGenericCommand(lua_State *lua, int raise_error) {
         goto cleanup;
     }
 
+    /* There are commands that are not allowed inside scripts. */
     if (cmd->flags & REDIS_CMD_NOSCRIPT) {
         luaPushError(lua, "This Redis command is not allowed from scripts");
         goto cleanup;
     }
 
-    if (cmd->flags & REDIS_CMD_WRITE && server.lua_random_dirty) {
-        luaPushError(lua,
-            "Write commands not allowed after non deterministic commands");
-        goto cleanup;
+    /* Write commands are forbidden against read-only slaves, or if a
+     * command marked as non-deterministic was already called in the context
+     * of this script. */
+    if (cmd->flags & REDIS_CMD_WRITE) {
+        if (server.lua_random_dirty) {
+            luaPushError(lua,
+                "Write commands not allowed after non deterministic commands");
+            goto cleanup;
+        } else if (server.masterhost && server.repl_slave_ro &&
+                   !(server.lua_caller->flags & REDIS_MASTER))
+        {
+            luaPushError(lua, shared.roslaveerr->ptr);
+            goto cleanup;
+        } else if (server.stop_writes_on_bgsave_err &&
+                   server.saveparamslen > 0 &&
+                   server.lastbgsave_status == REDIS_ERR)
+        {
+            luaPushError(lua, shared.bgsaveerr->ptr);
+            goto cleanup;
+        }
+    }
+
+    /* If we reached the memory limit configured via maxmemory, commands that
+     * could enlarge the memory usage are not allowed, but only if this is the
+     * first write in the context of this script, otherwise we can't stop
+     * in the middle. */
+    if (server.maxmemory && server.lua_write_dirty == 0 &&
+        (cmd->flags & REDIS_CMD_DENYOOM))
+    {
+        if (freeMemoryIfNeeded() == REDIS_ERR) {
+            luaPushError(lua, shared.oomerr->ptr);
+            goto cleanup;
+        }
     }
 
     if (cmd->flags & REDIS_CMD_RANDOM) server.lua_random_dirty = 1;
     if (cmd->flags & REDIS_CMD_WRITE) server.lua_write_dirty = 1;
 
     /* Run the command */
-    cmd->proc(c);
+    c->cmd = cmd;
+    call(c,REDIS_CALL_SLOWLOG | REDIS_CALL_STATS);
 
     /* Convert the result of the Redis command into a suitable Lua type.
      * The first thing we need is to create a single string from the client
@@ -208,6 +270,14 @@ int luaRedisGenericCommand(lua_State *lua, int raise_error) {
     }
     if (raise_error && reply[0] != '-') raise_error = 0;
     redisProtocolToLuaType(lua,reply);
+    /* Sort the output array if needed, assuming it is a non-null multi bulk
+     * reply as expected. */
+    if ((cmd->flags & REDIS_CMD_SORT_FOR_SCRIPT) &&
+        (reply[0] == '*' && reply[1] != '-')) {
+        /* Skip this step if command is SORT but output was already sorted */
+        if (cmd->proc != sortCommand || server.sort_dontsort)
+            luaSortArray(lua);
+    }
     sdsfree(reply);
 
 cleanup:
@@ -303,6 +373,8 @@ void luaLoadLib(lua_State *lua, const char *libname, lua_CFunction luafunc) {
 }
 
 LUALIB_API int (luaopen_cjson) (lua_State *L);
+LUALIB_API int (luaopen_struct) (lua_State *L);
+LUALIB_API int (luaopen_cmsgpack) (lua_State *L);
 
 void luaLoadLibraries(lua_State *lua) {
     luaLoadLib(lua, "", luaopen_base);
@@ -310,7 +382,9 @@ void luaLoadLibraries(lua_State *lua) {
     luaLoadLib(lua, LUA_STRLIBNAME, luaopen_string);
     luaLoadLib(lua, LUA_MATHLIBNAME, luaopen_math);
     luaLoadLib(lua, LUA_DBLIBNAME, luaopen_debug); 
-    luaLoadLib(lua, "cjson", luaopen_cjson); 
+    luaLoadLib(lua, "cjson", luaopen_cjson);
+    luaLoadLib(lua, "struct", luaopen_struct);
+    luaLoadLib(lua, "cmsgpack", luaopen_cmsgpack);
 
 #if 0 /* Stuff that we don't load currently, for sandboxing concerns. */
     luaLoadLib(lua, LUA_LOADLIBNAME, luaopen_package);
@@ -381,6 +455,18 @@ void scriptingInit(void) {
 
     lua_setglobal(lua,"math");
 
+    /* Add a helper funciton that we use to sort the multi bulk output of non
+     * deterministic commands, when containing 'false' elements. */
+    {
+        char *compare_func =    "function __redis__compare_helper(a,b)\n"
+                                "  if a == false then a = '' end\n"
+                                "  if b == false then b = '' end\n"
+                                "  return a<b\n"
+                                "end\n";
+        luaL_loadbuffer(lua,compare_func,strlen(compare_func),"cmp_func_def");
+        lua_pcall(lua,0,0,0);
+    }
+
     /* Create the (non connected) client that we use to execute Redis commands
      * inside the Lua interpreter.
      * Note: there is no need to create it again when this function is called
@@ -516,9 +602,9 @@ int luaCreateFunction(redisClient *c, lua_State *lua, char *funcname, robj *body
 
     funcdef = sdscat(funcdef,"function ");
     funcdef = sdscatlen(funcdef,funcname,42);
-    funcdef = sdscatlen(funcdef," ()\n",4);
+    funcdef = sdscatlen(funcdef,"() ",3);
     funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr));
-    funcdef = sdscatlen(funcdef,"\nend\n",5);
+    funcdef = sdscatlen(funcdef," end",4);
 
     if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"func definition")) {
         addReplyErrorFormat(c,"Error compiling script (new function): %s\n",