/* +------------------------------------+ * | Inspire Internet Relay Chat Daemon | * +------------------------------------+ * * InspIRCd: (C) 2002-2007 InspIRCd Development Team * See: http://www.inspircd.org/wiki/index.php/Credits * * This program is free but copyrighted software; see * the file COPYING for details. * * --------------------------------------------------- */ #include "inspircd.h" #include #include #include "users.h" #include "channels.h" #include "modules.h" #include "m_sqlv2.h" /* VERSION 2 API: With nonblocking (threaded) requests */ /* $ModDesc: SQL Service Provider module for all other m_sql* modules */ /* $CompileFlags: exec("mysql_config --include") */ /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */ /* $ModDep: m_sqlv2.h */ /* THE NONBLOCKING MYSQL API! * * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend * that instead, you should thread your program. This is what i've done here to allow for * asyncronous SQL requests via mysql. The way this works is as follows: * * The module spawns a thread via pthreads, and performs its mysql queries in this thread, * using a queue with priorities. There is a mutex on either end which prevents two threads * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the * worker thread wakes up, and checks if there is a request at the head of its queue. * If there is, it processes this request, blocking the worker thread but leaving the ircd * thread to go about its business as usual. During this period, the ircd thread is able * to insert futher pending requests into the queue. * * Once the processing of a request is complete, it is removed from the incoming queue to * an outgoing queue, and initialized as a 'response'. The worker thread then signals the * ircd thread (via a loopback socket) of the fact a result is available, by sending the * connection ID through the connection. * * The ircd thread then mutexes the queue once more, reads the outbound response off the head * of the queue, and sends it on its way to the original calling module. * * XXX: You might be asking "why doesnt he just send the response from within the worker thread?" * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not * threadsafe. This module is designed to be threadsafe and is careful with its use of threads, * however, if we were to call a module's OnRequest even from within a thread which was not the * one the module was originally instantiated upon, there is a chance of all hell breaking loose * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100% * gauranteed threadsafe!) * * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2 */ class SQLConnection; class Notifier; typedef std::map ConnMap; bool giveup = false; static Module* SQLModule = NULL; static Notifier* MessagePipe = NULL; int QueueFD = -1; #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224 #define mysql_field_count mysql_num_fields #endif typedef std::deque ResultQueue; /* A mutex to wrap around queue accesses */ pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER; pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER; pthread_mutex_t logging_mutex = PTHREAD_MUTEX_INITIALIZER; /** Represents a mysql result set */ class MySQLresult : public SQLresult { int currentrow; std::vector colnames; std::vector fieldlists; SQLfieldMap* fieldmap; SQLfieldMap fieldmap2; SQLfieldList emptyfieldlist; int rows; public: MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL) { /* A number of affected rows from from mysql_affected_rows. */ fieldlists.clear(); rows = 0; if (affected_rows >= 1) { rows = affected_rows; fieldlists.resize(rows); } unsigned int field_count = 0; if (res) { MYSQL_ROW row; int n = 0; while ((row = mysql_fetch_row(res))) { if (fieldlists.size() < (unsigned int)rows+1) { fieldlists.resize(fieldlists.size()+1); } field_count = 0; MYSQL_FIELD *fields = mysql_fetch_fields(res); if(mysql_num_fields(res) == 0) break; if (fields && mysql_num_fields(res)) { colnames.clear(); while (field_count < mysql_num_fields(res)) { std::string a = (fields[field_count].name ? fields[field_count].name : ""); std::string b = (row[field_count] ? row[field_count] : ""); SQLfield sqlf(b, !row[field_count]); colnames.push_back(a); fieldlists[n].push_back(sqlf); field_count++; } n++; } rows++; } mysql_free_result(res); } } MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0) { rows = 0; error = e; } ~MySQLresult() { } virtual int Rows() { return rows; } virtual int Cols() { return colnames.size(); } virtual std::string ColName(int column) { if (column < (int)colnames.size()) { return colnames[column]; } else { throw SQLbadColName(); } return ""; } virtual int ColNum(const std::string &column) { for (unsigned int i = 0; i < colnames.size(); i++) { if (column == colnames[i]) return i; } throw SQLbadColName(); return 0; } virtual SQLfield GetValue(int row, int column) { if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols())) { return fieldlists[row][column]; } throw SQLbadColName(); /* XXX: We never actually get here because of the throw */ return SQLfield("",true); } virtual SQLfieldList& GetRow() { if (currentrow < rows) return fieldlists[currentrow]; else return emptyfieldlist; } virtual SQLfieldMap& GetRowMap() { fieldmap2.clear(); if (currentrow < rows) { for (int i = 0; i < Cols(); i++) { fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i))); } currentrow++; } return fieldmap2; } virtual SQLfieldList* GetRowPtr() { SQLfieldList* fieldlist = new SQLfieldList(); if (currentrow < rows) { for (int i = 0; i < Rows(); i++) { fieldlist->push_back(fieldlists[currentrow][i]); } currentrow++; } return fieldlist; } virtual SQLfieldMap* GetRowMapPtr() { fieldmap = new SQLfieldMap(); if (currentrow < rows) { for (int i = 0; i < Cols(); i++) { fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i))); } currentrow++; } return fieldmap; } virtual void Free(SQLfieldMap* fm) { delete fm; } virtual void Free(SQLfieldList* fl) { delete fl; } }; class SQLConnection; void NotifyMainThread(SQLConnection* connection_with_new_result); /** Represents a connection to a mysql database */ class SQLConnection : public classbase { protected: MYSQL connection; MYSQL_RES *res; MYSQL_ROW row; SQLhost host; std::map thisrow; bool Enabled; public: QueryQueue queue; ResultQueue rq; // This constructor creates an SQLConnection object with the given credentials, but does not connect yet. SQLConnection(const SQLhost &hi) : host(hi), Enabled(false) { } ~SQLConnection() { Close(); } // This method connects to the database using the credentials supplied to the constructor, and returns // true upon success. bool Connect() { unsigned int timeout = 1; mysql_init(&connection); mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout); return mysql_real_connect(&connection, host.host.c_str(), host.user.c_str(), host.pass.c_str(), host.name.c_str(), host.port, NULL, 0); } void DoLeadingQuery() { if (!CheckConnection()) return; /* Parse the command string and dispatch it to mysql */ SQLrequest& req = queue.front(); /* Pointer to the buffer we screw around with substitution in */ char* query; /* Pointer to the current end of query, where we append new stuff */ char* queryend; /* Total length of the unescaped parameters */ unsigned long paramlen; /* Total length of query, used for binary-safety in mysql_real_query */ unsigned long querylength = 0; paramlen = 0; for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++) { paramlen += i->size(); } /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be. * sizeofquery + (totalparamlength*2) + 1 * * The +1 is for null-terminating the string for mysql_real_escape_string */ query = new char[req.query.q.length() + (paramlen*2) + 1]; queryend = query; /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting * the parameters into it... */ for(unsigned long i = 0; i < req.query.q.length(); i++) { if(req.query.q[i] == '?') { /* We found a place to substitute..what fun. * use mysql calls to escape and write the * escaped string onto the end of our query buffer, * then we "just" need to make sure queryend is * pointing at the right place. */ if(req.query.p.size()) { unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length()); queryend += len; req.query.p.pop_front(); } else break; } else { *queryend = req.query.q[i]; queryend++; } querylength++; } *queryend = 0; pthread_mutex_lock(&queue_mutex); req.query.q = query; pthread_mutex_unlock(&queue_mutex); if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length())) { /* Successfull query */ res = mysql_use_result(&connection); unsigned long rows = mysql_affected_rows(&connection); MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id); r->dbid = this->GetID(); r->query = req.query.q; /* Put this new result onto the results queue. * XXX: Remember to mutex the queue! */ pthread_mutex_lock(&results_mutex); rq.push_back(r); pthread_mutex_unlock(&results_mutex); } else { /* XXX: See /usr/include/mysql/mysqld_error.h for a list of * possible error numbers and error messages */ SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection)); MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id); r->dbid = this->GetID(); r->query = req.query.q; pthread_mutex_lock(&results_mutex); rq.push_back(r); pthread_mutex_unlock(&results_mutex); } /* Now signal the main thread that we've got a result to process. * Pass them this connection id as what to examine */ delete[] query; NotifyMainThread(this); } bool ConnectionLost() { if (&connection) { return (mysql_ping(&connection) != 0); } else return false; } bool CheckConnection() { if (ConnectionLost()) { return Connect(); } else return true; } std::string GetError() { return mysql_error(&connection); } const std::string& GetID() { return host.id; } std::string GetHost() { return host.host; } void SetEnable(bool Enable) { Enabled = Enable; } bool IsEnabled() { return Enabled; } void Close() { mysql_close(&connection); } const SQLhost& GetConfHost() { return host; } }; ConnMap Connections; bool HasHost(const SQLhost &host) { for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); iter++) { if (host == iter->second->GetConfHost()) return true; } return false; } bool HostInConf(ConfigReader* conf, const SQLhost &h) { for(int i = 0; i < conf->Enumerate("database"); i++) { SQLhost host; host.id = conf->ReadValue("database", "id", i); host.host = conf->ReadValue("database", "hostname", i); host.port = conf->ReadInteger("database", "port", i, true); host.name = conf->ReadValue("database", "name", i); host.user = conf->ReadValue("database", "username", i); host.pass = conf->ReadValue("database", "password", i); host.ssl = conf->ReadFlag("database", "ssl", i); if (h == host) return true; } return false; } void ClearOldConnections(ConfigReader* conf) { ConnMap::iterator i,safei; for (i = Connections.begin(); i != Connections.end(); i++) { if (!HostInConf(conf, i->second->GetConfHost())) { DELETE(i->second); safei = i; --i; Connections.erase(safei); } } } void ClearAllConnections() { ConnMap::iterator i; while ((i = Connections.begin()) != Connections.end()) { Connections.erase(i); DELETE(i->second); } } void ConnectDatabases(InspIRCd* ServerInstance) { for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++) { if (i->second->IsEnabled()) continue; i->second->SetEnable(true); if (!i->second->Connect()) { /* XXX: MUTEX */ pthread_mutex_lock(&logging_mutex); ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError()); i->second->SetEnable(false); pthread_mutex_unlock(&logging_mutex); } } } void LoadDatabases(ConfigReader* conf, InspIRCd* ServerInstance) { ClearOldConnections(conf); for (int j =0; j < conf->Enumerate("database"); j++) { SQLhost host; host.id = conf->ReadValue("database", "id", j); host.host = conf->ReadValue("database", "hostname", j); host.port = conf->ReadInteger("database", "port", j, true); host.name = conf->ReadValue("database", "name", j); host.user = conf->ReadValue("database", "username", j); host.pass = conf->ReadValue("database", "password", j); host.ssl = conf->ReadFlag("database", "ssl", j); if (HasHost(host)) continue; if (!host.id.empty() && !host.host.empty() && !host.name.empty() && !host.user.empty() && !host.pass.empty()) { SQLConnection* ThisSQL = new SQLConnection(host); Connections[host.id] = ThisSQL; } } ConnectDatabases(ServerInstance); } char FindCharId(const std::string &id) { char i = 1; for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i) { if (iter->first == id) { return i; } } return 0; } ConnMap::iterator GetCharId(char id) { char i = 1; for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i) { if (i == id) return iter; } return Connections.end(); } void NotifyMainThread(SQLConnection* connection_with_new_result) { /* Here we write() to the socket the main thread has open * and we connect()ed back to before our thread became active. * The main thread is using a nonblocking socket tied into * the socket engine, so they wont block and they'll receive * nearly instant notification. Because we're in a seperate * thread, we can just use standard connect(), and we can * block if we like. We just send the connection id of the * connection back. * * NOTE: We only send a single char down the connection, this * way we know it wont get a partial read at the other end if * the system is especially congested (see bug #263). * The function FindCharId translates a connection name into a * one character id, and GetCharId translates a character id * back into an iterator. */ char id = FindCharId(connection_with_new_result->GetID()); send(QueueFD, &id, 1, 0); } void* DispatcherThread(void* arg); /** Used by m_mysql to notify one thread when the other has a result */ class Notifier : public InspSocket { insp_sockaddr sock_us; socklen_t uslen; public: /* Create a socket on a random port. Let the tcp stack allocate us an available port */ #ifdef IPV6 Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000) #else Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000) #endif { uslen = sizeof(sock_us); if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen)) { throw ModuleException("Could not create random listening port on localhost"); } } Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip) { } /* Using getsockname and ntohs, we can determine which port number we were allocated */ int GetPort() { #ifdef IPV6 return ntohs(sock_us.sin6_port); #else return ntohs(sock_us.sin_port); #endif } virtual int OnIncomingConnection(int newsock, char* ip) { Notifier* n = new Notifier(this->Instance, newsock, ip); n = n; /* Stop bitching at me, GCC */ return true; } virtual bool OnDataReady() { char data = 0; /* NOTE: Only a single character is read so we know we * cant get a partial read. (We've been told that theres * data waiting, so we wont ever get EAGAIN) * The function GetCharId translates a single character * back into an iterator. */ if (Instance->SE->Recv(this, &data, 1, 0) > 0) { ConnMap::iterator iter = GetCharId(data); if (iter != Connections.end()) { /* Lock the mutex, send back the data */ pthread_mutex_lock(&results_mutex); ResultQueue::iterator n = iter->second->rq.begin(); (*n)->Send(); iter->second->rq.pop_front(); pthread_mutex_unlock(&results_mutex); return true; } /* No error, but unknown id */ return true; } /* Erk, error on descriptor! */ return false; } }; /** MySQL module */ class ModuleSQL : public Module { public: ConfigReader *Conf; InspIRCd* PublicServerInstance; pthread_t Dispatcher; int currid; bool rehashing; ModuleSQL(InspIRCd* Me) : Module::Module(Me), rehashing(false) { ServerInstance->Modules->UseInterface("SQLutils"); Conf = new ConfigReader(ServerInstance); PublicServerInstance = ServerInstance; currid = 0; SQLModule = this; MessagePipe = new Notifier(ServerInstance); pthread_attr_t attribs; pthread_attr_init(&attribs); pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED); if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0) { throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno))); } if (!ServerInstance->Modules->PublishFeature("SQL", this)) { /* Tell worker thread to exit NOW */ giveup = true; throw ModuleException("m_mysql: Unable to publish feature 'SQL'"); } ServerInstance->Modules->PublishInterface("SQL", this); } virtual ~ModuleSQL() { giveup = true; ClearAllConnections(); delete Conf; ServerInstance->Modules->UnpublishInterface("SQL", this); ServerInstance->Modules->UnpublishFeature("SQL"); ServerInstance->Modules->DoneWithInterface("SQLutils"); } void Implements(char* List) { List[I_OnRehash] = List[I_OnRequest] = 1; } unsigned long NewID() { if (currid+1 == 0) currid++; return ++currid; } char* OnRequest(Request* request) { if(strcmp(SQLREQID, request->GetId()) == 0) { SQLrequest* req = (SQLrequest*)request; /* XXX: Lock */ pthread_mutex_lock(&queue_mutex); ConnMap::iterator iter; char* returnval = NULL; if((iter = Connections.find(req->dbid)) != Connections.end()) { req->id = NewID(); iter->second->queue.push(*req); returnval = SQLSUCCESS; } else { req->error.Id(BAD_DBID); } pthread_mutex_unlock(&queue_mutex); /* XXX: Unlock */ return returnval; } return NULL; } virtual void OnRehash(userrec* user, const std::string ¶meter) { rehashing = true; } virtual Version GetVersion() { return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION); } }; void* DispatcherThread(void* arg) { ModuleSQL* thismodule = (ModuleSQL*)arg; LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance); /* Connect back to the Notifier */ if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1) { /* crap, we're out of sockets... */ return NULL; } insp_sockaddr addr; #ifdef IPV6 insp_aton("::1", &addr.sin6_addr); addr.sin6_family = AF_FAMILY; addr.sin6_port = htons(MessagePipe->GetPort()); #else insp_inaddr ia; insp_aton("127.0.0.1", &ia); addr.sin_family = AF_FAMILY; addr.sin_addr = ia; addr.sin_port = htons(MessagePipe->GetPort()); #endif if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1) { /* wtf, we cant connect to it, but we just created it! */ return NULL; } while (!giveup) { if (thismodule->rehashing) { /* XXX: Lock */ pthread_mutex_lock(&queue_mutex); thismodule->rehashing = false; LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance); pthread_mutex_unlock(&queue_mutex); /* XXX: Unlock */ } SQLConnection* conn = NULL; /* XXX: Lock here for safety */ pthread_mutex_lock(&queue_mutex); for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++) { if (i->second->queue.totalsize()) { conn = i->second; break; } } pthread_mutex_unlock(&queue_mutex); /* XXX: Unlock */ /* Theres an item! */ if (conn) { conn->DoLeadingQuery(); /* XXX: Lock */ pthread_mutex_lock(&queue_mutex); conn->queue.pop(); pthread_mutex_unlock(&queue_mutex); /* XXX: Unlock */ } usleep(50); } return NULL; } MODULE_INIT(ModuleSQL);