char *redisProtocolToLuaType_MultiBulk(lua_State *lua, char *reply);
int redis_math_random (lua_State *L);
int redis_math_randomseed (lua_State *L);
+void sha1hex(char *digest, char *script, size_t len);
/* Take a Redis reply in the Redis protocol format and convert it into a
* Lua type. Thanks to this function, and the introduction of not connected
* 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.
*
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;
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++) {
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
}
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] != '-')) {
+ luaSortArray(lua);
+ }
sdsfree(reply);
+ c->reply_bytes = 0;
cleanup:
/* Clean up. Command code may have changed argv/argc so we use the
return luaRedisGenericCommand(lua,0);
}
+/* This adds redis.sha1hex(string) to Lua scripts using the same hashing
+ * function used for sha1ing lua scripts. */
+int luaRedisSha1hexCommand(lua_State *lua) {
+ int argc = lua_gettop(lua);
+ char digest[41];
+ size_t len;
+ char *s;
+
+ if (argc != 1) {
+ luaPushError(lua, "wrong number of arguments");
+ return 1;
+ }
+
+ s = (char*)lua_tolstring(lua,1,&len);
+ sha1hex(digest,s,len);
+ lua_pushstring(lua,digest);
+ 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;
void luaMaskCountHook(lua_State *lua, lua_Debug *ar) {
long long elapsed;
REDIS_NOTUSED(ar);
+ REDIS_NOTUSED(lua);
elapsed = (ustime()/1000) - server.lua_time_start;
- if (elapsed >= server.lua_time_limit) {
- redisLog(REDIS_NOTICE,"Lua script aborted for max execution time after %lld milliseconds of running time.",elapsed);
- lua_pushstring(lua,"Script aborted for max execution time.");
+ if (elapsed >= server.lua_time_limit && server.lua_timedout == 0) {
+ redisLog(REDIS_WARNING,"Lua slow script detected: still in execution after %lld milliseconds. You can try killing the script using the SCRIPT KILL command.",elapsed);
+ server.lua_timedout = 1;
+ /* Once the script timeouts we reenter the event loop to permit others
+ * to call SCRIPT KILL or SHUTDOWN NOSAVE if needed. For this reason
+ * we need to mask the client executing the script from the event loop.
+ * If we don't do that the client may disconnect and could no longer be
+ * here when the EVAL command will return. */
+ aeDeleteFileEvent(server.el, server.lua_caller->fd, AE_READABLE);
+ }
+ if (server.lua_timedout)
+ aeProcessEvents(server.el, AE_FILE_EVENTS|AE_DONT_WAIT);
+ if (server.lua_kill) {
+ redisLog(REDIS_WARNING,"Lua script killed by user with SCRIPT KILL.");
+ lua_pushstring(lua,"Script killed by user with SCRIPT KILL...");
lua_error(lua);
}
}
}
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);
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);
#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_pushnumber(lua,REDIS_WARNING);
lua_settable(lua,-3);
+ /* redis.sha1hex */
+ lua_pushstring(lua, "sha1hex");
+ lua_pushcfunction(lua, luaRedisSha1hexCommand);
+ 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");
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
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;
}
scriptingInit();
}
-/* Hash the scripit into a SHA1 digest. We use this as Lua function name.
- * Digest should point to a 41 bytes buffer: 40 for SHA1 converted into an
+/* Perform the SHA1 of the input string. We use this both for hasing script
+ * bodies in order to obtain the Lua function name, and in the implementation
+ * of redis.sha1().
+ *
+ * 'digest' should point to a 41 bytes buffer: 40 for SHA1 converted into an
* hexadecimal number, plus 1 byte for null term. */
-void hashScript(char *digest, char *script, size_t len) {
+void sha1hex(char *digest, char *script, size_t len) {
SHA1_CTX ctx;
unsigned char hash[20];
char *cset = "0123456789abcdef";
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")) {
+ 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. */
* 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;
+ server.lua_write_dirty = 0;
/* Get the number of arguments that are keys */
if (getLongLongFromObjectOrReply(c,c->argv[2],&numkeys,NULL) != REDIS_OK)
funcname[1] = '_';
if (!evalsha) {
/* Hash the code if this is an EVAL call */
- hashScript(funcname+2,c->argv[1]->ptr,sdslen(c->argv[1]->ptr));
+ sha1hex(funcname+2,c->argv[1]->ptr,sdslen(c->argv[1]->ptr));
} else {
/* We already have the SHA if it is a EVALSHA */
int j;
* 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. */
- if (server.lua_time_limit > 0) {
+ 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);
- server.lua_time_start = ustime()/1000;
- } 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. */
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
+ * script timeout was detected. */
+ aeCreateFileEvent(server.el,c->fd,AE_READABLE,
+ readQueryFromClient,c);
+ }
+ server.lua_caller = NULL;
selectDb(c,server.lua_client->db->id); /* set DB ID from Lua client */
addReplyErrorFormat(c,"Error running script (call to %s): %s\n",
funcname, lua_tostring(lua,-1));
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 */
luaReplyToRedisReply(c,lua);
lua_gc(lua,LUA_GCSTEP,1);
funcname[0] = 'f';
funcname[1] = '_';
- hashScript(funcname+2,c->argv[2]->ptr,sdslen(c->argv[2]->ptr));
+ sha1hex(funcname+2,c->argv[2]->ptr,sdslen(c->argv[2]->ptr));
sha = sdsnewlen(funcname+2,40);
if (dictFind(server.lua_scripts,sha) == NULL) {
if (luaCreateFunction(c,server.lua,funcname,c->argv[2])
return;
}
}
+ addReplyBulkCBuffer(c,funcname+2,40);
sdsfree(sha);
- addReply(c,shared.ok);
+ } else if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"kill")) {
+ if (server.lua_caller == NULL) {
+ addReplySds(c,sdsnew("-NOTBUSY No scripts in execution right now.\r\n"));
+ } else if (server.lua_write_dirty) {
+ addReplySds(c,sdsnew("-UNKILLABLE Sorry the script already executed write commands against the dataset. You can either wait the script termination or kill the server in an hard way using the SHUTDOWN NOSAVE command.\r\n"));
+ } else {
+ server.lua_kill = 1;
+ addReply(c,shared.ok);
+ }
} else {
addReplyError(c, "Unknown SCRIPT subcommand or wrong # of args.");
}
projects / redis.git / blobdiff