#include "redis.h"
#include "sha1.h"
+#include "rand.h"
#include <lua.h>
#include <lauxlib.h>
#include <lualib.h>
#include <ctype.h>
+#include <math.h>
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);
/* 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
lua_settable(lua,-3);
}
-int luaRedisCommand(lua_State *lua) {
+int luaRedisGenericCommand(lua_State *lua, int raise_error) {
int j, argc = lua_gettop(lua);
struct redisCommand *cmd;
robj **argv;
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;
+ 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;
+ }
+
+ 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);
/* Convert the result of the Redis command into a suitable Lua type.
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);
sdsfree(reply);
+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);
+}
+
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);
}
}
+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);
+
+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);
+
+#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
+}
+
+/* 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);
/* Initialize a dictionary we use to map SHAs to scripts.
* This is useful for replication, as we need to replicate EVALSHA
/* 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. */
/* 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");
+
/* Create the (non connected) client that we use to execute Redis commands
- * inside the Lua interpreter */
- server.lua_client = createClient(-1);
- server.lua_client->flags |= 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;
+ }
server.lua = lua;
}
+/* 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();
+}
+
/* 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
* hexadecimal number, plus 1 byte for null term. */
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_<hex sha1 sum>
+ *
+ * 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," ()\n",4);
+ funcdef = sdscatlen(funcdef,body->ptr,sdslen(body->ptr));
+ funcdef = sdscatlen(funcdef,"\nend\n",5);
+
+ 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 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;
+ /* 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)
return;
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);
-
- /* 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),c->argv[1]);
- redisAssert(retval == DICT_OK);
- incrRefCount(c->argv[1]);
- }
+ redisAssert(!lua_isnil(lua,1));
}
/* Populate the argv and keys table accordingly to the arguments that
* 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) {
+ 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);
}
/* 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 (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;
}
+ 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 (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);
}
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] = '_';
+ hashScript(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.");
+ }
+}
projects / redis.git / blobdiff