redisClient *c = server.lua_client;
sds reply;
+ /* Require at least one argument */
+ if (argc == 0) {
+ luaPushError(lua,
+ "Please specify at least one argument for redis.call()");
+ return 1;
+ }
+
/* Build the arguments vector */
argv = zmalloc(sizeof(robj*)*argc);
for (j = 0; j < argc; j++) {
* 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);
+ c->reply_bytes = 0;
cleanup:
/* Clean up. Command code may have changed argv/argc so we use the
return 1;
}
+/* Returns a table with a single field 'field' set to the string value
+ * passed as argument. This helper function is handy when returning
+ * a Redis Protocol error or status reply from Lua:
+ *
+ * return redis.error_reply("ERR Some Error")
+ * return redis.status_reply("ERR Some Error")
+ */
+int luaRedisReturnSingleFieldTable(lua_State *lua, char *field) {
+ if (lua_gettop(lua) != 1 || lua_type(lua,-1) != LUA_TSTRING) {
+ luaPushError(lua, "wrong number or type of arguments");
+ return 1;
+ }
+
+ lua_newtable(lua);
+ lua_pushstring(lua, field);
+ lua_pushvalue(lua, -3);
+ lua_settable(lua, -3);
+ return 1;
+}
+
+int luaRedisErrorReplyCommand(lua_State *lua) {
+ return luaRedisReturnSingleFieldTable(lua,"err");
+}
+
+int luaRedisStatusReplyCommand(lua_State *lua) {
+ return luaRedisReturnSingleFieldTable(lua,"ok");
+}
+
int luaLogCommand(lua_State *lua) {
int j, argc = lua_gettop(lua);
int level;
#endif
}
+/* Remove a functions that we don't want to expose to the Redis scripting
+ * environment. */
+void luaRemoveUnsupportedFunctions(lua_State *lua) {
+ lua_pushnil(lua);
+ lua_setglobal(lua,"loadfile");
+}
+
+/* This function installs metamethods in the global table _G that prevent
+ * the creation of globals accidentally.
+ *
+ * It should be the last to be called in the scripting engine initialization
+ * sequence, because it may interact with creation of globals. */
+void scriptingEnableGlobalsProtection(lua_State *lua) {
+ char *s[32];
+ sds code = sdsempty();
+ int j = 0;
+
+ /* strict.lua from: http://metalua.luaforge.net/src/lib/strict.lua.html.
+ * Modified to be adapted to Redis. */
+ s[j++]="local mt = {}\n";
+ s[j++]="setmetatable(_G, mt)\n";
+ s[j++]="mt.__newindex = function (t, n, v)\n";
+ s[j++]=" if debug.getinfo(2) then\n";
+ s[j++]=" local w = debug.getinfo(2, \"S\").what\n";
+ s[j++]=" if w ~= \"main\" and w ~= \"C\" then\n";
+ s[j++]=" error(\"Script attempted to create global variable '\"..tostring(n)..\"'\", 2)\n";
+ s[j++]=" end\n";
+ s[j++]=" end\n";
+ s[j++]=" rawset(t, n, v)\n";
+ s[j++]="end\n";
+ s[j++]="mt.__index = function (t, n)\n";
+ s[j++]=" if debug.getinfo(2) and debug.getinfo(2, \"S\").what ~= \"C\" then\n";
+ s[j++]=" error(\"Script attempted to access unexisting global variable '\"..tostring(n)..\"'\", 2)\n";
+ s[j++]=" end\n";
+ s[j++]=" return rawget(t, n)\n";
+ s[j++]="end\n";
+ s[j++]=NULL;
+
+ for (j = 0; s[j] != NULL; j++) code = sdscatlen(code,s[j],strlen(s[j]));
+ luaL_loadbuffer(lua,code,sdslen(code),"@enable_strict_lua");
+ lua_pcall(lua,0,0,0);
+ sdsfree(code);
+}
+
/* Initialize the scripting environment.
* It is possible to call this function to reset the scripting environment
* assuming that we call scriptingRelease() before.
* See scriptingReset() for more information. */
void scriptingInit(void) {
lua_State *lua = lua_open();
+
luaLoadLibraries(lua);
+ luaRemoveUnsupportedFunctions(lua);
/* Initialize a dictionary we use to map SHAs to scripts.
* This is useful for replication, as we need to replicate EVALSHA
lua_pushcfunction(lua, luaRedisSha1hexCommand);
lua_settable(lua, -3);
+ /* redis.NIL */
+ lua_pushstring(lua, "NIL");
+ lua_newtable(lua);
+ lua_pushstring(lua, "nilbulk");
+ lua_pushboolean(lua, 1);
+ lua_settable(lua, -3);
+ lua_settable(lua, -3);
+
+ /* redis.error_reply and redis.status_reply */
+ lua_pushstring(lua, "error_reply");
+ lua_pushcfunction(lua, luaRedisErrorReplyCommand);
+ lua_settable(lua, -3);
+ lua_pushstring(lua, "status_reply");
+ lua_pushcfunction(lua, luaRedisStatusReplyCommand);
+ lua_settable(lua, -3);
+
/* Finally set the table as 'redis' global var. */
lua_setglobal(lua,"redis");
" if b == false then b = '' end\n"
" return a<b\n"
"end\n";
- luaL_loadbuffer(lua,compare_func,strlen(compare_func),"cmp_func_def");
+ luaL_loadbuffer(lua,compare_func,strlen(compare_func),"@cmp_func_def");
lua_pcall(lua,0,0,0);
}
server.lua_client->flags |= REDIS_LUA_CLIENT;
}
+ /* Lua beginners ofter don't use "local", this is likely to introduce
+ * subtle bugs in their code. To prevent problems we protect accesses
+ * to global variables. */
+ scriptingEnableGlobalsProtection(lua);
+
server.lua = lua;
}
addReplyLongLong(c,(long long)lua_tonumber(lua,-1));
break;
case LUA_TTABLE:
- /* We need to check if it is an array, an error, or a status reply.
- * Error are returned as a single element table with 'err' field.
- * Status replies are returned as single elment table with 'ok' field */
+ /* The table can be an array or it may be in a special format that
+ * Lua uses to return special Redis protocol data types.
+ *
+ * 1) Errors are retuned as a single element table with 'err' field.
+ * 2) Status reply are returned as a single element table with 'ok'
+ * field.
+ * 3) A Redis nil bulk reply is returned as a single element table
+ * with 'nilbulk' field set to true.
+ *
+ * All the rest is considered just an array and is translated into
+ * a Redis multi bulk reply. */
+
+ /* Nil bulk reply */
+ lua_pushstring(lua,"nilbulk");
+ lua_gettable(lua,-2);
+ t = lua_type(lua,-1);
+ if (t == LUA_TBOOLEAN) {
+ addReply(c,shared.nullbulk);
+ lua_pop(lua,2);
+ return;
+ }
+ lua_pop(lua,1);
+
+ /* Error reply */
lua_pushstring(lua,"err");
lua_gettable(lua,-2);
t = lua_type(lua,-1);
lua_pop(lua,2);
return;
}
-
lua_pop(lua,1);
+
+ /* Status reply */
lua_pushstring(lua,"ok");
lua_gettable(lua,-2);
t = lua_type(lua,-1);
sdsfree(ok);
lua_pop(lua,1);
} else {
+ /* Multi bulk reply. */
void *replylen = addDeferredMultiBulkLength(c);
int j = 1, mbulklen = 0;
funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr));
funcdef = sdscatlen(funcdef," end",4);
- if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"func definition")) {
+ if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"@user_script")) {
addReplyErrorFormat(c,"Error compiling script (new function): %s\n",
lua_tostring(lua,-1));
lua_pop(lua,1);
lua_State *lua = server.lua;
char funcname[43];
long long numkeys;
+ int delhook = 0;
/* We want the same PRNG sequence at every call so that our PRNG is
* not affected by external state. */
* is running for too much time.
* We set the hook only if the time limit is enabled as the hook will
* make the Lua script execution slower. */
+ server.lua_caller = c;
+ server.lua_time_start = ustime()/1000;
+ server.lua_kill = 0;
if (server.lua_time_limit > 0 && server.masterhost == NULL) {
lua_sethook(lua,luaMaskCountHook,LUA_MASKCOUNT,100000);
- } else {
- lua_sethook(lua,luaMaskCountHook,0,0);
+ delhook = 1;
}
/* At this point whatever this script was never seen before or if it was
* already defined, we can call it. We have zero arguments and expect
* a single return value. */
- server.lua_caller = c;
- server.lua_time_start = ustime()/1000;
- server.lua_kill = 0;
if (lua_pcall(lua,0,1,0)) {
+ if (delhook) lua_sethook(lua,luaMaskCountHook,0,0); /* Disable hook */
if (server.lua_timedout) {
server.lua_timedout = 0;
/* Restore the readable handler that was unregistered when the
lua_gc(lua,LUA_GCCOLLECT,0);
return;
}
+ if (delhook) lua_sethook(lua,luaMaskCountHook,0,0); /* Disable hook */
server.lua_timedout = 0;
server.lua_caller = NULL;
selectDb(c,server.lua_client->db->id); /* set DB ID from Lua client */
projects / redis.git / blobdiff