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 */
30 /* THE NONBLOCKING MYSQL API!
32 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
33 * that instead, you should thread your program. This is what i've done here to allow for
34 * asyncronous SQL requests via mysql. The way this works is as follows:
36 * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
37 * using a queue with priorities. There is a mutex on either end which prevents two threads
38 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
39 * worker thread wakes up, and checks if there is a request at the head of its queue.
40 * If there is, it processes this request, blocking the worker thread but leaving the ircd
41 * thread to go about its business as usual. During this period, the ircd thread is able
42 * to insert futher pending requests into the queue.
44 * Once the processing of a request is complete, it is removed from the incoming queue to
45 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
46 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
47 * connection ID through the connection.
49 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
50 * of the queue, and sends it on its way to the original calling module.
52 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
53 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
54 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
55 * however, if we were to call a module's OnRequest even from within a thread which was not the
56 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
57 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
58 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
59 * gauranteed threadsafe!)
61 * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
69 typedef std::map<std::string, SQLConnection*> ConnMap;
71 static Module* SQLModule = NULL;
72 static Notifier* MessagePipe = NULL;
76 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
77 #define mysql_field_count mysql_num_fields
80 typedef std::deque<SQLresult*> ResultQueue;
82 /* A mutex to wrap around queue accesses */
83 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
85 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
87 pthread_mutex_t logging_mutex = PTHREAD_MUTEX_INITIALIZER;
89 /** Represents a mysql result set
91 class MySQLresult : public SQLresult
94 std::vector<std::string> colnames;
95 std::vector<SQLfieldList> fieldlists;
96 SQLfieldMap* fieldmap;
97 SQLfieldMap fieldmap2;
98 SQLfieldList emptyfieldlist;
102 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
104 /* A number of affected rows from from mysql_affected_rows.
108 if (affected_rows >= 1)
110 rows = affected_rows;
111 fieldlists.resize(rows);
113 unsigned int field_count = 0;
118 while ((row = mysql_fetch_row(res)))
120 if (fieldlists.size() < (unsigned int)rows+1)
122 fieldlists.resize(fieldlists.size()+1);
125 MYSQL_FIELD *fields = mysql_fetch_fields(res);
126 if(mysql_num_fields(res) == 0)
128 if (fields && mysql_num_fields(res))
131 while (field_count < mysql_num_fields(res))
133 std::string a = (fields[field_count].name ? fields[field_count].name : "");
134 std::string b = (row[field_count] ? row[field_count] : "");
135 SQLfield sqlf(b, !row[field_count]);
136 colnames.push_back(a);
137 fieldlists[n].push_back(sqlf);
144 mysql_free_result(res);
148 MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
165 return colnames.size();
168 virtual std::string ColName(int column)
170 if (column < (int)colnames.size())
172 return colnames[column];
176 throw SQLbadColName();
181 virtual int ColNum(const std::string &column)
183 for (unsigned int i = 0; i < colnames.size(); i++)
185 if (column == colnames[i])
188 throw SQLbadColName();
192 virtual SQLfield GetValue(int row, int column)
194 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
196 return fieldlists[row][column];
199 throw SQLbadColName();
201 /* XXX: We never actually get here because of the throw */
202 return SQLfield("",true);
205 virtual SQLfieldList& GetRow()
207 if (currentrow < rows)
208 return fieldlists[currentrow];
210 return emptyfieldlist;
213 virtual SQLfieldMap& GetRowMap()
217 if (currentrow < rows)
219 for (int i = 0; i < Cols(); i++)
221 fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
229 virtual SQLfieldList* GetRowPtr()
231 SQLfieldList* fieldlist = new SQLfieldList();
233 if (currentrow < rows)
235 for (int i = 0; i < Rows(); i++)
237 fieldlist->push_back(fieldlists[currentrow][i]);
244 virtual SQLfieldMap* GetRowMapPtr()
246 fieldmap = new SQLfieldMap();
248 if (currentrow < rows)
250 for (int i = 0; i < Cols(); i++)
252 fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
260 virtual void Free(SQLfieldMap* fm)
265 virtual void Free(SQLfieldList* fl)
273 void NotifyMainThread(SQLConnection* connection_with_new_result);
275 /** Represents a connection to a mysql database
277 class SQLConnection : public classbase
285 std::map<std::string,std::string> thisrow;
293 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
294 SQLConnection(const SQLhost &hi) : host(hi), Enabled(false)
303 // This method connects to the database using the credentials supplied to the constructor, and returns
304 // true upon success.
307 unsigned int timeout = 1;
308 mysql_init(&connection);
309 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
310 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);
313 void DoLeadingQuery()
315 if (!CheckConnection())
318 /* Parse the command string and dispatch it to mysql */
319 SQLrequest& req = queue.front();
321 /* Pointer to the buffer we screw around with substitution in */
324 /* Pointer to the current end of query, where we append new stuff */
327 /* Total length of the unescaped parameters */
328 unsigned long paramlen;
330 /* Total length of query, used for binary-safety in mysql_real_query */
331 unsigned long querylength = 0;
335 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
337 paramlen += i->size();
340 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
341 * sizeofquery + (totalparamlength*2) + 1
343 * The +1 is for null-terminating the string for mysql_real_escape_string
346 query = new char[req.query.q.length() + (paramlen*2) + 1];
349 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
350 * the parameters into it...
353 for(unsigned long i = 0; i < req.query.q.length(); i++)
355 if(req.query.q[i] == '?')
357 /* We found a place to substitute..what fun.
358 * use mysql calls to escape and write the
359 * escaped string onto the end of our query buffer,
360 * then we "just" need to make sure queryend is
361 * pointing at the right place.
363 if(req.query.p.size())
365 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
368 req.query.p.pop_front();
375 *queryend = req.query.q[i];
383 pthread_mutex_lock(&queue_mutex);
385 pthread_mutex_unlock(&queue_mutex);
387 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
389 /* Successfull query */
390 res = mysql_use_result(&connection);
391 unsigned long rows = mysql_affected_rows(&connection);
392 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
393 r->dbid = this->GetID();
394 r->query = req.query.q;
395 /* Put this new result onto the results queue.
396 * XXX: Remember to mutex the queue!
398 pthread_mutex_lock(&results_mutex);
400 pthread_mutex_unlock(&results_mutex);
404 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
405 * possible error numbers and error messages */
406 SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
407 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
408 r->dbid = this->GetID();
409 r->query = req.query.q;
411 pthread_mutex_lock(&results_mutex);
413 pthread_mutex_unlock(&results_mutex);
416 /* Now signal the main thread that we've got a result to process.
417 * Pass them this connection id as what to examine
422 NotifyMainThread(this);
425 bool ConnectionLost()
428 return (mysql_ping(&connection) != 0);
433 bool CheckConnection()
435 if (ConnectionLost()) {
441 std::string GetError()
443 return mysql_error(&connection);
446 const std::string& GetID()
451 std::string GetHost()
456 void SetEnable(bool Enable)
468 mysql_close(&connection);
471 const SQLhost& GetConfHost()
480 bool HasHost(const SQLhost &host)
482 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); iter++)
484 if (host == iter->second->GetConfHost())
490 bool HostInConf(ConfigReader* conf, const SQLhost &h)
492 for(int i = 0; i < conf->Enumerate("database"); i++)
495 host.id = conf->ReadValue("database", "id", i);
496 host.host = conf->ReadValue("database", "hostname", i);
497 host.port = conf->ReadInteger("database", "port", i, true);
498 host.name = conf->ReadValue("database", "name", i);
499 host.user = conf->ReadValue("database", "username", i);
500 host.pass = conf->ReadValue("database", "password", i);
501 host.ssl = conf->ReadFlag("database", "ssl", i);
508 void ClearOldConnections(ConfigReader* conf)
510 ConnMap::iterator i,safei;
511 for (i = Connections.begin(); i != Connections.end(); i++)
513 if (!HostInConf(conf, i->second->GetConfHost()))
518 Connections.erase(safei);
523 void ClearAllConnections()
526 while ((i = Connections.begin()) != Connections.end())
528 Connections.erase(i);
533 void ConnectDatabases(InspIRCd* ServerInstance)
535 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
537 if (i->second->IsEnabled())
540 i->second->SetEnable(true);
541 if (!i->second->Connect())
544 pthread_mutex_lock(&logging_mutex);
545 ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
546 i->second->SetEnable(false);
547 pthread_mutex_unlock(&logging_mutex);
552 void LoadDatabases(ConfigReader* conf, InspIRCd* ServerInstance)
554 ClearOldConnections(conf);
555 for (int j =0; j < conf->Enumerate("database"); j++)
558 host.id = conf->ReadValue("database", "id", j);
559 host.host = conf->ReadValue("database", "hostname", j);
560 host.port = conf->ReadInteger("database", "port", j, true);
561 host.name = conf->ReadValue("database", "name", j);
562 host.user = conf->ReadValue("database", "username", j);
563 host.pass = conf->ReadValue("database", "password", j);
564 host.ssl = conf->ReadFlag("database", "ssl", j);
569 if (!host.id.empty() && !host.host.empty() && !host.name.empty() && !host.user.empty() && !host.pass.empty())
571 SQLConnection* ThisSQL = new SQLConnection(host);
572 Connections[host.id] = ThisSQL;
575 ConnectDatabases(ServerInstance);
578 char FindCharId(const std::string &id)
581 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i)
583 if (iter->first == id)
591 ConnMap::iterator GetCharId(char id)
594 for (ConnMap::iterator iter = Connections.begin(); iter != Connections.end(); ++iter, ++i)
599 return Connections.end();
602 void NotifyMainThread(SQLConnection* connection_with_new_result)
604 /* Here we write() to the socket the main thread has open
605 * and we connect()ed back to before our thread became active.
606 * The main thread is using a nonblocking socket tied into
607 * the socket engine, so they wont block and they'll receive
608 * nearly instant notification. Because we're in a seperate
609 * thread, we can just use standard connect(), and we can
610 * block if we like. We just send the connection id of the
613 * NOTE: We only send a single char down the connection, this
614 * way we know it wont get a partial read at the other end if
615 * the system is especially congested (see bug #263).
616 * The function FindCharId translates a connection name into a
617 * one character id, and GetCharId translates a character id
618 * back into an iterator.
620 char id = FindCharId(connection_with_new_result->GetID());
621 send(QueueFD, &id, 1, 0);
624 void* DispatcherThread(void* arg);
626 /** Used by m_mysql to notify one thread when the other has a result
628 class Notifier : public BufferedSocket
630 insp_sockaddr sock_us;
636 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
638 Notifier(InspIRCd* SI) : BufferedSocket(SI, "::1", 0, true, 3000)
640 Notifier(InspIRCd* SI) : BufferedSocket(SI, "127.0.0.1", 0, true, 3000)
643 uslen = sizeof(sock_us);
644 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
646 throw ModuleException("Could not create random listening port on localhost");
650 Notifier(InspIRCd* SI, int newfd, char* ip) : BufferedSocket(SI, newfd, ip)
654 /* Using getsockname and ntohs, we can determine which port number we were allocated */
658 return ntohs(sock_us.sin6_port);
660 return ntohs(sock_us.sin_port);
664 virtual int OnIncomingConnection(int newsock, char* ip)
666 Notifier* n = new Notifier(this->Instance, newsock, ip);
667 n = n; /* Stop bitching at me, GCC */
671 virtual bool OnDataReady()
674 /* NOTE: Only a single character is read so we know we
675 * cant get a partial read. (We've been told that theres
676 * data waiting, so we wont ever get EAGAIN)
677 * The function GetCharId translates a single character
678 * back into an iterator.
680 if (Instance->SE->Recv(this, &data, 1, 0) > 0)
682 ConnMap::iterator iter = GetCharId(data);
683 if (iter != Connections.end())
685 /* Lock the mutex, send back the data */
686 pthread_mutex_lock(&results_mutex);
687 ResultQueue::iterator n = iter->second->rq.begin();
689 iter->second->rq.pop_front();
690 pthread_mutex_unlock(&results_mutex);
693 /* No error, but unknown id */
697 /* Erk, error on descriptor! */
704 class ModuleSQL : public Module
709 InspIRCd* PublicServerInstance;
710 pthread_t Dispatcher;
714 ModuleSQL(InspIRCd* Me)
715 : Module::Module(Me), rehashing(false)
717 ServerInstance->Modules->UseInterface("SQLutils");
719 Conf = new ConfigReader(ServerInstance);
720 PublicServerInstance = ServerInstance;
724 MessagePipe = new Notifier(ServerInstance);
726 pthread_attr_t attribs;
727 pthread_attr_init(&attribs);
728 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
729 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
731 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
734 if (!ServerInstance->Modules->PublishFeature("SQL", this))
736 /* Tell worker thread to exit NOW */
738 throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
741 ServerInstance->Modules->PublishInterface("SQL", this);
742 Implementation eventlist[] = { I_OnRehash, I_OnRequest };
743 ServerInstance->Modules->Attach(eventlist, this, 2);
749 ClearAllConnections();
751 ServerInstance->Modules->UnpublishInterface("SQL", this);
752 ServerInstance->Modules->UnpublishFeature("SQL");
753 ServerInstance->Modules->DoneWithInterface("SQLutils");
757 void Implements(char* List)
759 List[I_OnRehash] = List[I_OnRequest] = 1;
762 unsigned long NewID()
769 char* OnRequest(Request* request)
771 if(strcmp(SQLREQID, request->GetId()) == 0)
773 SQLrequest* req = (SQLrequest*)request;
776 pthread_mutex_lock(&queue_mutex);
778 ConnMap::iterator iter;
780 char* returnval = NULL;
782 if((iter = Connections.find(req->dbid)) != Connections.end())
785 iter->second->queue.push(*req);
786 returnval = SQLSUCCESS;
790 req->error.Id(BAD_DBID);
793 pthread_mutex_unlock(&queue_mutex);
802 virtual void OnRehash(User* user, const std::string ¶meter)
807 virtual Version GetVersion()
809 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION);
814 void* DispatcherThread(void* arg)
816 ModuleSQL* thismodule = (ModuleSQL*)arg;
817 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
819 /* Connect back to the Notifier */
821 if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
823 /* crap, we're out of sockets... */
830 insp_aton("::1", &addr.sin6_addr);
831 addr.sin6_family = AF_FAMILY;
832 addr.sin6_port = htons(MessagePipe->GetPort());
835 insp_aton("127.0.0.1", &ia);
836 addr.sin_family = AF_FAMILY;
838 addr.sin_port = htons(MessagePipe->GetPort());
841 if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
843 /* wtf, we cant connect to it, but we just created it! */
849 if (thismodule->rehashing)
852 pthread_mutex_lock(&queue_mutex);
853 thismodule->rehashing = false;
854 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
855 pthread_mutex_unlock(&queue_mutex);
859 SQLConnection* conn = NULL;
860 /* XXX: Lock here for safety */
861 pthread_mutex_lock(&queue_mutex);
862 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
864 if (i->second->queue.totalsize())
870 pthread_mutex_unlock(&queue_mutex);
873 /* Theres an item! */
876 conn->DoLeadingQuery();
879 pthread_mutex_lock(&queue_mutex);
881 pthread_mutex_unlock(&queue_mutex);
891 MODULE_INIT(ModuleSQL)