X-Git-Url: https://git.saurik.com/redis.git/blobdiff_plain/3bb818df405e667087fe3336cd91159790f63981..7eb850ef0e437323e2d84157ddc2e6e82af57bbc:/src/scripting.c?ds=sidebyside diff --git a/src/scripting.c b/src/scripting.c index 469d7870..35b654f7 100644 --- a/src/scripting.c +++ b/src/scripting.c @@ -1,16 +1,21 @@ #include "redis.h" #include "sha1.h" +#include "rand.h" #include #include #include #include +#include char *redisProtocolToLuaType_Int(lua_State *lua, char *reply); char *redisProtocolToLuaType_Bulk(lua_State *lua, char *reply); char *redisProtocolToLuaType_Status(lua_State *lua, char *reply); char *redisProtocolToLuaType_Error(lua_State *lua, char *reply); 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 @@ -23,7 +28,7 @@ char *redisProtocolToLuaType_MultiBulk(lua_State *lua, char *reply); * 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. * @@ -124,13 +129,51 @@ void luaPushError(lua_State *lua, char *error) { lua_settable(lua,-3); } -int luaRedisCommand(lua_State *lua) { +/* 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; robj **argv; 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++) { @@ -154,25 +197,70 @@ int luaRedisCommand(lua_State *lua) { return 1; } + /* Setup our fake client for command execution */ + c->argv = argv; + c->argc = argc; + /* Command lookup */ cmd = lookupCommand(argv[0]->ptr); if (!cmd || ((cmd->arity > 0 && cmd->arity != argc) || (argc < -cmd->arity))) { - for (j = 0; j < argc; j++) decrRefCount(argv[j]); - zfree(argv); if (cmd) luaPushError(lua, "Wrong number of args calling Redis command From Lua script"); else luaPushError(lua,"Unknown Redis command called from Lua script"); - return 1; + goto cleanup; } - /* Run the command in the context of a fake client */ - c->argv = argv; - c->argc = argc; - cmd->proc(c); + /* 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; + } + + /* 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 */ + 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 @@ -188,15 +276,59 @@ int luaRedisCommand(lua_State *lua) { reply = sdscatlen(reply,o->ptr,sdslen(o->ptr)); listDelNode(c->reply,listFirst(c->reply)); } + 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 * argv/argc of the client instead of the local variables. */ for (j = 0; j < c->argc; j++) decrRefCount(c->argv[j]); zfree(c->argv); + if (raise_error) { + /* If we are here we should have an error in the stack, in the + * form of a table with an "err" field. Extract the string to + * return the plain error. */ + lua_pushstring(lua,"err"); + lua_gettable(lua,-2); + return lua_error(lua); + } + return 1; +} + +int luaRedisCallCommand(lua_State *lua) { + return luaRedisGenericCommand(lua,1); +} + +int luaRedisPCallCommand(lua_State *lua) { + 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; } @@ -238,25 +370,124 @@ int luaLogCommand(lua_State *lua) { 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); } } +void luaLoadLib(lua_State *lua, const char *libname, lua_CFunction luafunc) { + lua_pushcfunction(lua, luafunc); + lua_pushstring(lua, libname); + lua_call(lua, 1, 0); +} + +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_TABLIBNAME, luaopen_table); + 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, "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); + luaLoadLib(lua, LUA_OSLIBNAME, luaopen_os); +#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(); - luaL_openlibs(lua); + + 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 + * as EVAL, so we need to remember the associated script. */ + server.lua_scripts = dictCreate(&dbDictType,NULL); /* Register the redis commands table and fields */ lua_newtable(lua); /* redis.call */ lua_pushstring(lua,"call"); - lua_pushcfunction(lua,luaRedisCommand); + lua_pushcfunction(lua,luaRedisCallCommand); + lua_settable(lua,-3); + + /* redis.pcall */ + lua_pushstring(lua,"pcall"); + lua_pushcfunction(lua,luaRedisPCallCommand); lua_settable(lua,-3); /* redis.log and log levels. */ @@ -280,21 +511,75 @@ void scriptingInit(void) { lua_pushnumber(lua,REDIS_WARNING); lua_settable(lua,-3); + /* redis.sha1hex */ + lua_pushstring(lua, "sha1hex"); + lua_pushcfunction(lua, luaRedisSha1hexCommand); + lua_settable(lua, -3); + /* Finally set the table as 'redis' global var. */ lua_setglobal(lua,"redis"); + /* Replace math.random and math.randomseed with our implementations. */ + lua_getglobal(lua,"math"); + + lua_pushstring(lua,"random"); + lua_pushcfunction(lua,redis_math_random); + lua_settable(lua,-3); + + lua_pushstring(lua,"randomseed"); + lua_pushcfunction(lua,redis_math_randomseed); + lua_settable(lua,-3); + + 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 aflags |= REDIS_LUA_CLIENT; + * inside the Lua interpreter. + * Note: there is no need to create it again when this function is called + * by scriptingReset(). */ + if (server.lua_client == NULL) { + server.lua_client = createClient(-1); + 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; } -/* 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 +/* Release resources related to Lua scripting. + * This function is used in order to reset the scripting environment. */ +void scriptingRelease(void) { + dictRelease(server.lua_scripts); + lua_close(server.lua); +} + +void scriptingReset(void) { + scriptingRelease(); + scriptingInit(); +} + +/* 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"; @@ -388,10 +673,71 @@ void luaSetGlobalArray(lua_State *lua, char *var, robj **elev, int elec) { lua_setglobal(lua,var); } +/* Define a lua function with the specified function name and body. + * The function name musts be a 2 characters long string, since all the + * functions we defined in the Lua context are in the form: + * + * f_ + * + * On success REDIS_OK is returned, and nothing is left on the Lua stack. + * On error REDIS_ERR is returned and an appropriate error is set in the + * client context. */ +int luaCreateFunction(redisClient *c, lua_State *lua, char *funcname, robj *body) { + sds funcdef = sdsempty(); + + funcdef = sdscat(funcdef,"function "); + funcdef = sdscatlen(funcdef,funcname,42); + funcdef = sdscatlen(funcdef,"() ",3); + funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr)); + funcdef = sdscatlen(funcdef," end",4); + + 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); + sdsfree(funcdef); + return REDIS_ERR; + } + sdsfree(funcdef); + if (lua_pcall(lua,0,0,0)) { + addReplyErrorFormat(c,"Error running script (new function): %s\n", + lua_tostring(lua,-1)); + lua_pop(lua,1); + return REDIS_ERR; + } + + /* We also save a SHA1 -> Original script map in a dictionary + * so that we can replicate / write in the AOF all the + * EVALSHA commands as EVAL using the original script. */ + { + int retval = dictAdd(server.lua_scripts, + sdsnewlen(funcname+2,40),body); + redisAssertWithInfo(c,NULL,retval == DICT_OK); + incrRefCount(body); + } + return REDIS_OK; +} + void evalGenericCommand(redisClient *c, int evalsha) { 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. */ + 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; + server.lua_write_dirty = 0; /* Get the number of arguments that are keys */ if (getLongLongFromObjectOrReply(c,c->argv[2],&numkeys,NULL) != REDIS_OK) @@ -407,7 +753,7 @@ void evalGenericCommand(redisClient *c, int evalsha) { 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; @@ -418,43 +764,21 @@ void evalGenericCommand(redisClient *c, int evalsha) { funcname[42] = '\0'; } + /* Try to lookup the Lua function */ lua_getglobal(lua, funcname); if (lua_isnil(lua,1)) { - sds funcdef; - + lua_pop(lua,1); /* remove the nil from the stack */ /* Function not defined... let's define it if we have the * body of the funciton. If this is an EVALSHA call we can just * return an error. */ if (evalsha) { addReply(c, shared.noscripterr); - lua_pop(lua,1); /* remove the nil from the stack */ - return; - } - funcdef = sdsempty(); - - lua_pop(lua,1); /* remove the nil from the stack */ - funcdef = sdscat(funcdef,"function "); - funcdef = sdscatlen(funcdef,funcname,42); - funcdef = sdscatlen(funcdef," ()\n",4); - funcdef = sdscatlen(funcdef,c->argv[1]->ptr,sdslen(c->argv[1]->ptr)); - funcdef = sdscatlen(funcdef,"\nend\n",5); - /* printf("Defining:\n%s\n",funcdef); */ - - if (luaL_loadbuffer(lua,funcdef,sdslen(funcdef),"func definition")) { - addReplyErrorFormat(c,"Error compiling script (new function): %s\n", - lua_tostring(lua,-1)); - lua_pop(lua,1); - sdsfree(funcdef); - return; - } - sdsfree(funcdef); - if (lua_pcall(lua,0,0,0)) { - addReplyErrorFormat(c,"Error running script (new function): %s\n", - lua_tostring(lua,-1)); - lua_pop(lua,1); return; } + if (luaCreateFunction(c,lua,funcname,c->argv[1]) == REDIS_ERR) return; + /* Now the following is guaranteed to return non nil */ lua_getglobal(lua, funcname); + redisAssert(!lua_isnil(lua,1)); } /* Populate the argv and keys table accordingly to the arguments that @@ -469,17 +793,27 @@ void evalGenericCommand(redisClient *c, int evalsha) { * 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)); @@ -487,9 +821,31 @@ void evalGenericCommand(redisClient *c, int evalsha) { 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); + + /* If we have slaves attached we want to replicate this command as + * EVAL instead of EVALSHA. We do this also in the AOF as currently there + * is no easy way to propagate a command in a different way in the AOF + * and in the replication link. + * + * IMPROVEMENT POSSIBLE: + * 1) Replicate this command as EVALSHA in the AOF. + * 2) Remember what slave already received a given script, and replicate + * the EVALSHA against this slaves when possible. + */ + if (evalsha) { + robj *script = dictFetchValue(server.lua_scripts,c->argv[1]->ptr); + + redisAssertWithInfo(c,NULL,script != NULL); + rewriteClientCommandArgument(c,0, + resetRefCount(createStringObject("EVAL",4))); + rewriteClientCommandArgument(c,1,script); + } } void evalCommand(redisClient *c) { @@ -507,3 +863,92 @@ void evalShaCommand(redisClient *c) { } evalGenericCommand(c,1); } + +/* We replace math.random() with our implementation that is not affected + * by specific libc random() implementations and will output the same sequence + * (for the same seed) in every arch. */ + +/* The following implementation is the one shipped with Lua itself but with + * rand() replaced by redisLrand48(). */ +int redis_math_random (lua_State *L) { + /* the `%' avoids the (rare) case of r==1, and is needed also because on + some systems (SunOS!) `rand()' may return a value larger than RAND_MAX */ + lua_Number r = (lua_Number)(redisLrand48()%REDIS_LRAND48_MAX) / + (lua_Number)REDIS_LRAND48_MAX; + switch (lua_gettop(L)) { /* check number of arguments */ + case 0: { /* no arguments */ + lua_pushnumber(L, r); /* Number between 0 and 1 */ + break; + } + case 1: { /* only upper limit */ + int u = luaL_checkint(L, 1); + luaL_argcheck(L, 1<=u, 1, "interval is empty"); + lua_pushnumber(L, floor(r*u)+1); /* int between 1 and `u' */ + break; + } + case 2: { /* lower and upper limits */ + int l = luaL_checkint(L, 1); + int u = luaL_checkint(L, 2); + luaL_argcheck(L, l<=u, 2, "interval is empty"); + lua_pushnumber(L, floor(r*(u-l+1))+l); /* int between `l' and `u' */ + break; + } + default: return luaL_error(L, "wrong number of arguments"); + } + return 1; +} + +int redis_math_randomseed (lua_State *L) { + redisSrand48(luaL_checkint(L, 1)); + return 0; +} + +/* --------------------------------------------------------------------------- + * SCRIPT command for script environment introspection and control + * ------------------------------------------------------------------------- */ + +void scriptCommand(redisClient *c) { + if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"flush")) { + scriptingReset(); + addReply(c,shared.ok); + server.dirty++; /* Replicating this command is a good idea. */ + } else if (c->argc >= 2 && !strcasecmp(c->argv[1]->ptr,"exists")) { + int j; + + addReplyMultiBulkLen(c, c->argc-2); + for (j = 2; j < c->argc; j++) { + if (dictFind(server.lua_scripts,c->argv[j]->ptr)) + addReply(c,shared.cone); + else + addReply(c,shared.czero); + } + } else if (c->argc == 3 && !strcasecmp(c->argv[1]->ptr,"load")) { + char funcname[43]; + sds sha; + + funcname[0] = 'f'; + funcname[1] = '_'; + 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]) + == REDIS_ERR) { + sdsfree(sha); + return; + } + } + addReplyBulkCBuffer(c,funcname+2,40); + sdsfree(sha); + } else if (c->argc == 2 && !strcasecmp(c->argv[1]->ptr,"kill")) { + if (server.lua_caller == NULL) { + addReplyError(c,"No scripts in execution right now."); + } else if (server.lua_write_dirty) { + addReplyError(c, "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."); + } else { + server.lua_kill = 1; + addReply(c,shared.ok); + } + } else { + addReplyError(c, "Unknown SCRIPT subcommand or wrong # of args."); + } +}