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
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;
* 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 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;
#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");
" 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;
}
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 = 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. */
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. */
+ 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 */
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])
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.");
+ addReplySds(c,sdsnew("-NOTBUSY No scripts in execution right now.\r\n"));
} 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.");
+ 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);
projects / redis.git / blobdiff