1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2007 InspIRCd Development Team
6 * See: http://www.inspircd.org/wiki/index.php/Credits
8 * This program is free but copyrighted software; see
9 * the file COPYING for details.
11 * ---------------------------------------------------
22 /* VERSION 2 API: With nonblocking (threaded) requests */
24 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
25 /* $CompileFlags: exec("mysql_config --include") */
26 /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */
27 /* $ModDep: m_sqlv2.h */
29 /* THE NONBLOCKING MYSQL API!
31 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
32 * that instead, you should thread your program. This is what i've done here to allow for
33 * asyncronous SQL requests via mysql. The way this works is as follows:
35 * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
36 * using a queue with priorities. There is a mutex on either end which prevents two threads
37 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
38 * worker thread wakes up, and checks if there is a request at the head of its queue.
39 * If there is, it processes this request, blocking the worker thread but leaving the ircd
40 * thread to go about its business as usual. During this period, the ircd thread is able
41 * to insert futher pending requests into the queue.
43 * Once the processing of a request is complete, it is removed from the incoming queue to
44 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
45 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
46 * connection ID through the connection.
48 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
49 * of the queue, and sends it on its way to the original calling module.
51 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
52 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
53 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
54 * however, if we were to call a module's OnRequest even from within a thread which was not the
55 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
56 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
57 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
58 * gauranteed threadsafe!)
60 * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
68 typedef std::map<std::string, SQLConnection*> ConnMap;
70 static Module* SQLModule = NULL;
71 static Notifier* MessagePipe = NULL;
75 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
76 #define mysql_field_count mysql_num_fields
79 typedef std::deque<SQLresult*> ResultQueue;
81 /* A mutex to wrap around queue accesses */
82 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
84 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
86 pthread_mutex_t logging_mutex = PTHREAD_MUTEX_INITIALIZER;
88 /** Represents a mysql result set
90 class MySQLresult : public SQLresult
93 std::vector<std::string> colnames;
94 std::vector<SQLfieldList> fieldlists;
95 SQLfieldMap* fieldmap;
96 SQLfieldMap fieldmap2;
97 SQLfieldList emptyfieldlist;
101 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
103 /* A number of affected rows from from mysql_affected_rows.
107 if (affected_rows >= 1)
109 rows = affected_rows;
110 fieldlists.resize(rows);
112 unsigned int field_count = 0;
117 while ((row = mysql_fetch_row(res)))
119 if (fieldlists.size() < (unsigned int)rows+1)
121 fieldlists.resize(fieldlists.size()+1);
124 MYSQL_FIELD *fields = mysql_fetch_fields(res);
125 if(mysql_num_fields(res) == 0)
127 if (fields && mysql_num_fields(res))
130 while (field_count < mysql_num_fields(res))
132 std::string a = (fields[field_count].name ? fields[field_count].name : "");
133 std::string b = (row[field_count] ? row[field_count] : "");
134 SQLfield sqlf(b, !row[field_count]);
135 colnames.push_back(a);
136 fieldlists[n].push_back(sqlf);
143 mysql_free_result(res);
147 MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
164 return colnames.size();
167 virtual std::string ColName(int column)
169 if (column < (int)colnames.size())
171 return colnames[column];
175 throw SQLbadColName();
180 virtual int ColNum(const std::string &column)
182 for (unsigned int i = 0; i < colnames.size(); i++)
184 if (column == colnames[i])
187 throw SQLbadColName();
191 virtual SQLfield GetValue(int row, int column)
193 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
195 return fieldlists[row][column];
198 throw SQLbadColName();
200 /* XXX: We never actually get here because of the throw */
201 return SQLfield("",true);
204 virtual SQLfieldList& GetRow()
206 if (currentrow < rows)
207 return fieldlists[currentrow];
209 return emptyfieldlist;
212 virtual SQLfieldMap& GetRowMap()
216 if (currentrow < rows)
218 for (int i = 0; i < Cols(); i++)
220 fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
228 virtual SQLfieldList* GetRowPtr()
230 SQLfieldList* fieldlist = new SQLfieldList();
232 if (currentrow < rows)
234 for (int i = 0; i < Rows(); i++)
236 fieldlist->push_back(fieldlists[currentrow][i]);
243 virtual SQLfieldMap* GetRowMapPtr()
245 fieldmap = new SQLfieldMap();
247 if (currentrow < rows)
249 for (int i = 0; i < Cols(); i++)
251 fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
259 virtual void Free(SQLfieldMap* fm)
264 virtual void Free(SQLfieldList* fl)
272 void NotifyMainThread(SQLConnection* connection_with_new_result);
274 /** Represents a connection to a mysql database
276 class SQLConnection : public classbase
284 std::map<std::string,std::string> thisrow;
292 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
293 SQLConnection(const SQLhost &hi) : host(hi), Enabled(false)
302 // This method connects to the database using the credentials supplied to the constructor, and returns
303 // true upon success.
306 unsigned int timeout = 1;
307 mysql_init(&connection);
308 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
309 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);
312 void DoLeadingQuery()
314 if (!CheckConnection())
317 /* Parse the command string and dispatch it to mysql */
318 SQLrequest& req = queue.front();
320 /* Pointer to the buffer we screw around with substitution in */
323 /* Pointer to the current end of query, where we append new stuff */
326 /* Total length of the unescaped parameters */
327 unsigned long paramlen;
329 /* Total length of query, used for binary-safety in mysql_real_query */
330 unsigned long querylength = 0;
334 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
336 paramlen += i->size();
339 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
340 * sizeofquery + (totalparamlength*2) + 1
342 * The +1 is for null-terminating the string for mysql_real_escape_string
345 query = new char[req.query.q.length() + (paramlen*2) + 1];
348 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
349 * the parameters into it...
352 for(unsigned long i = 0; i < req.query.q.length(); i++)
354 if(req.query.q[i] == '?')
356 /* We found a place to substitute..what fun.
357 * use mysql calls to escape and write the
358 * escaped string onto the end of our query buffer,
359 * then we "just" need to make sure queryend is
360 * pointing at the right place.
362 if(req.query.p.size())
364 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
367 req.query.p.pop_front();
374 *queryend = req.query.q[i];
382 pthread_mutex_lock(&queue_mutex);
384 pthread_mutex_unlock(&queue_mutex);
386 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
388 /* Successfull query */
389 res = mysql_use_result(&connection);
390 unsigned long rows = mysql_affected_rows(&connection);
391 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
392 r->dbid = this->GetID();
393 r->query = req.query.q;
394 /* Put this new result onto the results queue.
395 * XXX: Remember to mutex the queue!
397 pthread_mutex_lock(&results_mutex);
399 pthread_mutex_unlock(&results_mutex);
403 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
404 * possible error numbers and error messages */
405 SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
406 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
407 r->dbid = this->GetID();
408 r->query = req.query.q;
410 pthread_mutex_lock(&results_mutex);
412 pthread_mutex_unlock(&results_mutex);
415 /* Now signal the main thread that we've got a result to process.
416 * Pass them this connection id as what to examine
421 NotifyMainThread(this);
424 bool ConnectionLost()
427 return (mysql_ping(&connection) != 0);
432 bool CheckConnection()
434 if (ConnectionLost()) {
440 std::string GetError()
442 return mysql_error(&connection);
445 const std::string& GetID()
450 std::string GetHost()
455 void SetEnable(bool Enable)
467 mysql_close(&connection);
470 const SQLhost& GetConfHost()
479 bool HasHost(const SQLhost &host)
481 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); iter++)
483 if (host == iter->second->GetConfHost())
489 bool HostInConf(ConfigReader* conf, const SQLhost &h)
491 for(int i = 0; i < conf->Enumerate("database"); i++)
494 host.id = conf->ReadValue("database", "id", i);
495 host.host = conf->ReadValue("database", "hostname", i);
496 host.port = conf->ReadInteger("database", "port", i, true);
497 host.name = conf->ReadValue("database", "name", i);
498 host.user = conf->ReadValue("database", "username", i);
499 host.pass = conf->ReadValue("database", "password", i);
500 host.ssl = conf->ReadFlag("database", "ssl", i);
507 void ClearOldConnections(ConfigReader* conf)
509 ConnMap::iterator i,safei;
510 for (i = Connections.begin(); i != Connections.end(); i++)
512 if (!HostInConf(conf, i->second->GetConfHost()))
517 Connections.erase(safei);
522 void ClearAllConnections()
525 while ((i = Connections.begin()) != Connections.end())
527 Connections.erase(i);
532 void ConnectDatabases(InspIRCd* ServerInstance)
534 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
536 if (i->second->IsEnabled())
539 i->second->SetEnable(true);
540 if (!i->second->Connect())
543 pthread_mutex_lock(&logging_mutex);
544 ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
545 i->second->SetEnable(false);
546 pthread_mutex_unlock(&logging_mutex);
551 void LoadDatabases(ConfigReader* conf, InspIRCd* ServerInstance)
553 ClearOldConnections(conf);
554 for (int j =0; j < conf->Enumerate("database"); j++)
557 host.id = conf->ReadValue("database", "id", j);
558 host.host = conf->ReadValue("database", "hostname", j);
559 host.port = conf->ReadInteger("database", "port", j, true);
560 host.name = conf->ReadValue("database", "name", j);
561 host.user = conf->ReadValue("database", "username", j);
562 host.pass = conf->ReadValue("database", "password", j);
563 host.ssl = conf->ReadFlag("database", "ssl", j);
568 if (!host.id.empty() && !host.host.empty() && !host.name.empty() && !host.user.empty() && !host.pass.empty())
570 SQLConnection* ThisSQL = new SQLConnection(host);
571 Connections[host.id] = ThisSQL;
574 ConnectDatabases(ServerInstance);
577 char FindCharId(const std::string &id)
580 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i)
582 if (iter->first == id)
590 ConnMap::iterator GetCharId(char id)
593 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i)
598 return Connections.end();
601 void NotifyMainThread(SQLConnection* connection_with_new_result)
603 /* Here we write() to the socket the main thread has open
604 * and we connect()ed back to before our thread became active.
605 * The main thread is using a nonblocking socket tied into
606 * the socket engine, so they wont block and they'll receive
607 * nearly instant notification. Because we're in a seperate
608 * thread, we can just use standard connect(), and we can
609 * block if we like. We just send the connection id of the
612 * NOTE: We only send a single char down the connection, this
613 * way we know it wont get a partial read at the other end if
614 * the system is especially congested (see bug #263).
615 * The function FindCharId translates a connection name into a
616 * one character id, and GetCharId translates a character id
617 * back into an iterator.
619 char id = FindCharId(connection_with_new_result->GetID());
620 send(QueueFD, &id, 1, 0);
623 void* DispatcherThread(void* arg);
625 /** Used by m_mysql to notify one thread when the other has a result
627 class Notifier : public InspSocket
629 insp_sockaddr sock_us;
635 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
637 Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000)
639 Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000)
642 uslen = sizeof(sock_us);
643 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
645 throw ModuleException("Could not create random listening port on localhost");
649 Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip)
653 /* Using getsockname and ntohs, we can determine which port number we were allocated */
657 return ntohs(sock_us.sin6_port);
659 return ntohs(sock_us.sin_port);
663 virtual int OnIncomingConnection(int newsock, char* ip)
665 Notifier* n = new Notifier(this->Instance, newsock, ip);
666 n = n; /* Stop bitching at me, GCC */
670 virtual bool OnDataReady()
673 /* NOTE: Only a single character is read so we know we
674 * cant get a partial read. (We've been told that theres
675 * data waiting, so we wont ever get EAGAIN)
676 * The function GetCharId translates a single character
677 * back into an iterator.
679 if (read(this->GetFd(), &data, 1) > 0)
681 ConnMap::iterator iter = GetCharId(data);
682 if (iter != Connections.end())
684 /* Lock the mutex, send back the data */
685 pthread_mutex_lock(&results_mutex);
686 ResultQueue::iterator n = iter->second->rq.begin();
688 iter->second->rq.pop_front();
689 pthread_mutex_unlock(&results_mutex);
692 /* No error, but unknown id */
696 /* Erk, error on descriptor! */
703 class ModuleSQL : public Module
708 InspIRCd* PublicServerInstance;
709 pthread_t Dispatcher;
713 ModuleSQL(InspIRCd* Me)
714 : Module::Module(Me), rehashing(false)
716 ServerInstance->UseInterface("SQLutils");
718 Conf = new ConfigReader(ServerInstance);
719 PublicServerInstance = ServerInstance;
723 MessagePipe = new Notifier(ServerInstance);
725 pthread_attr_t attribs;
726 pthread_attr_init(&attribs);
727 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
728 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
730 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
733 if (!ServerInstance->PublishFeature("SQL", this))
735 /* Tell worker thread to exit NOW */
737 throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
740 ServerInstance->PublishInterface("SQL", this);
746 ClearAllConnections();
748 ServerInstance->UnpublishInterface("SQL", this);
749 ServerInstance->UnpublishFeature("SQL");
750 ServerInstance->DoneWithInterface("SQLutils");
754 void Implements(char* List)
756 List[I_OnRehash] = List[I_OnRequest] = 1;
759 unsigned long NewID()
766 char* OnRequest(Request* request)
768 if(strcmp(SQLREQID, request->GetId()) == 0)
770 SQLrequest* req = (SQLrequest*)request;
773 pthread_mutex_lock(&queue_mutex);
775 ConnMap::iterator iter;
777 char* returnval = NULL;
779 if((iter = Connections.find(req->dbid)) != Connections.end())
782 iter->second->queue.push(*req);
783 returnval = SQLSUCCESS;
787 req->error.Id(BAD_DBID);
790 pthread_mutex_unlock(&queue_mutex);
799 virtual void OnRehash(userrec* user, const std::string ¶meter)
804 virtual Version GetVersion()
806 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION);
811 void* DispatcherThread(void* arg)
813 ModuleSQL* thismodule = (ModuleSQL*)arg;
814 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
816 /* Connect back to the Notifier */
818 if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
820 /* crap, we're out of sockets... */
827 insp_aton("::1", &addr.sin6_addr);
828 addr.sin6_family = AF_FAMILY;
829 addr.sin6_port = htons(MessagePipe->GetPort());
832 insp_aton("127.0.0.1", &ia);
833 addr.sin_family = AF_FAMILY;
835 addr.sin_port = htons(MessagePipe->GetPort());
838 if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
840 /* wtf, we cant connect to it, but we just created it! */
846 if (thismodule->rehashing)
849 pthread_mutex_lock(&queue_mutex);
850 thismodule->rehashing = false;
851 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
852 pthread_mutex_unlock(&queue_mutex);
856 SQLConnection* conn = NULL;
857 /* XXX: Lock here for safety */
858 pthread_mutex_lock(&queue_mutex);
859 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
861 if (i->second->queue.totalsize())
867 pthread_mutex_unlock(&queue_mutex);
870 /* Theres an item! */
873 conn->DoLeadingQuery();
876 pthread_mutex_lock(&queue_mutex);
878 pthread_mutex_unlock(&queue_mutex);
888 MODULE_INIT(ModuleSQL);