1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd is copyright (C) 2002-2004 ChatSpike-Dev.
7 * <brain@chatspike.net>
8 * <Craig@chatspike.net>
10 * Written by Craig Edwards, Craig McLure, and others.
11 * This program is free but copyrighted software; see
12 * the file COPYING for details.
14 * ---------------------------------------------------
29 /* VERSION 2 API: With nonblocking (threaded) requests */
31 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
32 /* $CompileFlags: `mysql_config --include` */
33 /* $LinkerFlags: `mysql_config --libs_r` `perl extra/mysql_rpath.pl` */
34 /* $ModDep: m_sqlv2.h */
36 /* THE NONBLOCKING MYSQL API!
38 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
39 * that instead, you should thread your program. This is what i've done here to allow for
40 * asyncronous SQL requests via mysql. The way this works is as follows:
42 * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
43 * using a queue with priorities. There is a mutex on either end which prevents two threads
44 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
45 * worker thread wakes up, and checks if there is a request at the head of its queue.
46 * If there is, it processes this request, blocking the worker thread but leaving the ircd
47 * thread to go about its business as usual. During this period, the ircd thread is able
48 * to insert futher pending requests into the queue.
50 * Once the processing of a request is complete, it is removed from the incoming queue to
51 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
52 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
53 * connection ID through the connection.
55 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
56 * of the queue, and sends it on its way to the original calling module.
58 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
59 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
60 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
61 * however, if we were to call a module's OnRequest even from within a thread which was not the
62 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
63 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
64 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
65 * gauranteed threadsafe!)
67 * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
75 typedef std::map<std::string, SQLConnection*> ConnMap;
77 static Module* SQLModule = NULL;
78 static Notifier* MessagePipe = NULL;
82 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
83 #define mysql_field_count mysql_num_fields
86 typedef std::deque<SQLresult*> ResultQueue;
88 /** Represents a mysql query queue
90 class QueryQueue : public classbase
93 typedef std::deque<SQLrequest> ReqDeque;
95 ReqDeque priority; /* The priority queue */
96 ReqDeque normal; /* The 'normal' queue */
97 enum { PRI, NOR, NON } which; /* Which queue the currently active element is at the front of */
105 void push(const SQLrequest &q)
108 priority.push_back(q);
115 if((which == PRI) && priority.size())
117 priority.pop_front();
119 else if((which == NOR) && normal.size())
127 /* Silently do nothing if there was no element to pop() */
135 return priority.front();
137 return normal.front();
142 return priority.front();
148 return normal.front();
151 /* This will probably result in a segfault,
152 * but the caller should have checked totalsize()
153 * first so..meh - moron :p
156 return priority.front();
160 std::pair<int, int> size()
162 return std::make_pair(priority.size(), normal.size());
167 return priority.size() + normal.size();
170 void PurgeModule(Module* mod)
172 DoPurgeModule(mod, priority);
173 DoPurgeModule(mod, normal);
177 void DoPurgeModule(Module* mod, ReqDeque& q)
179 for(ReqDeque::iterator iter = q.begin(); iter != q.end(); iter++)
181 if(iter->GetSource() == mod)
183 if(iter->id == front().id)
185 /* It's the currently active query.. :x */
186 iter->SetSource(NULL);
190 /* It hasn't been executed yet..just remove it */
191 iter = q.erase(iter);
198 /* A mutex to wrap around queue accesses */
199 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
201 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
203 /** Represents a mysql result set
205 class MySQLresult : public SQLresult
208 //std::vector<std::map<std::string,std::string> > results;
209 std::vector<std::string> colnames;
210 std::vector<SQLfieldList> fieldlists;
211 SQLfieldMap* fieldmap;
212 SQLfieldMap fieldmap2;
213 SQLfieldList emptyfieldlist;
217 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
219 /* A number of affected rows from from mysql_affected_rows.
223 if (affected_rows >= 1)
225 rows = affected_rows;
226 fieldlists.resize(rows);
228 unsigned int field_count = 0;
233 while ((row = mysql_fetch_row(res)))
235 if (fieldlists.size() < (unsigned int)rows+1)
237 fieldlists.resize(fieldlists.size()+1);
240 MYSQL_FIELD *fields = mysql_fetch_fields(res);
241 if(mysql_num_fields(res) == 0)
243 if (fields && mysql_num_fields(res))
246 while (field_count < mysql_num_fields(res))
248 std::string a = (fields[field_count].name ? fields[field_count].name : "");
249 std::string b = (row[field_count] ? row[field_count] : "");
250 SQLfield sqlf(b, !row[field_count]);
251 colnames.push_back(a);
252 fieldlists[n].push_back(sqlf);
259 mysql_free_result(res);
263 MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
280 return colnames.size();
283 virtual std::string ColName(int column)
285 if (column < (int)colnames.size())
287 return colnames[column];
291 throw SQLbadColName();
296 virtual int ColNum(const std::string &column)
298 for (unsigned int i = 0; i < colnames.size(); i++)
300 if (column == colnames[i])
303 throw SQLbadColName();
307 virtual SQLfield GetValue(int row, int column)
309 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
311 return fieldlists[row][column];
314 throw SQLbadColName();
316 /* XXX: We never actually get here because of the throw */
317 return SQLfield("",true);
320 virtual SQLfieldList& GetRow()
322 if (currentrow < rows)
323 return fieldlists[currentrow];
325 return emptyfieldlist;
328 virtual SQLfieldMap& GetRowMap()
332 if (currentrow < rows)
334 for (int i = 0; i < Cols(); i++)
336 fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
344 virtual SQLfieldList* GetRowPtr()
346 SQLfieldList* fieldlist = new SQLfieldList();
348 if (currentrow < rows)
350 for (int i = 0; i < Rows(); i++)
352 fieldlist->push_back(fieldlists[currentrow][i]);
359 virtual SQLfieldMap* GetRowMapPtr()
361 fieldmap = new SQLfieldMap();
363 if (currentrow < rows)
365 for (int i = 0; i < Cols(); i++)
367 fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
375 virtual void Free(SQLfieldMap* fm)
380 virtual void Free(SQLfieldList* fl)
388 void NotifyMainThread(SQLConnection* connection_with_new_result);
390 /** Represents a connection to a mysql database
392 class SQLConnection : public classbase
403 std::map<std::string,std::string> thisrow;
412 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
413 SQLConnection(const std::string &thishost, const std::string &thisuser, const std::string &thispass, const std::string &thisdb, const std::string &myid) : host(thishost), user(thisuser), pass(thispass), db(thisdb), Enabled(true), id(myid)
417 // This method connects to the database using the credentials supplied to the constructor, and returns
418 // true upon success.
421 unsigned int timeout = 1;
422 mysql_init(&connection);
423 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
424 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
427 void DoLeadingQuery()
429 if (!CheckConnection())
432 /* Parse the command string and dispatch it to mysql */
433 SQLrequest& req = queue.front();
435 /* Pointer to the buffer we screw around with substitution in */
438 /* Pointer to the current end of query, where we append new stuff */
441 /* Total length of the unescaped parameters */
442 unsigned long paramlen;
444 /* Total length of query, used for binary-safety in mysql_real_query */
445 unsigned long querylength = 0;
449 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
451 paramlen += i->size();
454 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
455 * sizeofquery + (totalparamlength*2) + 1
457 * The +1 is for null-terminating the string for mysql_real_escape_string
460 query = new char[req.query.q.length() + (paramlen*2)];
463 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
464 * the parameters into it...
467 for(unsigned long i = 0; i < req.query.q.length(); i++)
469 if(req.query.q[i] == '?')
471 /* We found a place to substitute..what fun.
472 * use mysql calls to escape and write the
473 * escaped string onto the end of our query buffer,
474 * then we "just" need to make sure queryend is
475 * pointing at the right place.
477 if(req.query.p.size())
479 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
482 req.query.p.pop_front();
489 *queryend = req.query.q[i];
497 pthread_mutex_lock(&queue_mutex);
499 pthread_mutex_unlock(&queue_mutex);
501 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
503 /* Successfull query */
504 res = mysql_use_result(&connection);
505 unsigned long rows = mysql_affected_rows(&connection);
506 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
507 r->dbid = this->GetID();
508 r->query = req.query.q;
509 /* Put this new result onto the results queue.
510 * XXX: Remember to mutex the queue!
512 pthread_mutex_lock(&results_mutex);
514 pthread_mutex_unlock(&results_mutex);
518 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
519 * possible error numbers and error messages */
520 SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
521 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
522 r->dbid = this->GetID();
523 r->query = req.query.q;
525 pthread_mutex_lock(&results_mutex);
527 pthread_mutex_unlock(&results_mutex);
530 /* Now signal the main thread that we've got a result to process.
531 * Pass them this connection id as what to examine
536 NotifyMainThread(this);
539 bool ConnectionLost()
542 return (mysql_ping(&connection) != 0);
547 bool CheckConnection()
549 if (ConnectionLost()) {
555 std::string GetError()
557 return mysql_error(&connection);
560 const std::string& GetID()
565 std::string GetHost()
570 void SetEnable(bool Enable)
584 void ConnectDatabases(InspIRCd* ServerInstance)
586 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
588 i->second->SetEnable(true);
589 if (i->second->Connect())
591 ServerInstance->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
595 ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
596 i->second->SetEnable(false);
602 void LoadDatabases(ConfigReader* ThisConf, InspIRCd* ServerInstance)
604 ServerInstance->Log(DEFAULT,"SQL: Loading database settings");
606 ServerInstance->Log(DEBUG,"Cleared connections");
607 for (int j =0; j < ThisConf->Enumerate("database"); j++)
609 std::string db = ThisConf->ReadValue("database","name",j);
610 std::string user = ThisConf->ReadValue("database","username",j);
611 std::string pass = ThisConf->ReadValue("database","password",j);
612 std::string host = ThisConf->ReadValue("database","hostname",j);
613 std::string id = ThisConf->ReadValue("database","id",j);
614 ServerInstance->Log(DEBUG,"Read database settings");
615 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
617 SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
618 ServerInstance->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
619 Connections[id] = ThisSQL;
620 ServerInstance->Log(DEBUG,"Pushed back connection");
623 ConnectDatabases(ServerInstance);
626 void NotifyMainThread(SQLConnection* connection_with_new_result)
628 /* Here we write() to the socket the main thread has open
629 * and we connect()ed back to before our thread became active.
630 * The main thread is using a nonblocking socket tied into
631 * the socket engine, so they wont block and they'll receive
632 * nearly instant notification. Because we're in a seperate
633 * thread, we can just use standard connect(), and we can
634 * block if we like. We just send the connection id of the
637 send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0);
640 void* DispatcherThread(void* arg);
642 /** Used by m_mysql to notify one thread when the other has a result
644 class Notifier : public InspSocket
646 insp_sockaddr sock_us;
652 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
654 Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000)
656 Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000)
659 uslen = sizeof(sock_us);
660 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
662 throw ModuleException("Could not create random listening port on localhost");
666 Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip)
668 Instance->Log(DEBUG,"Constructor of new socket");
671 /* Using getsockname and ntohs, we can determine which port number we were allocated */
675 return ntohs(sock_us.sin6_port);
677 return ntohs(sock_us.sin_port);
681 virtual int OnIncomingConnection(int newsock, char* ip)
683 Instance->Log(DEBUG,"Inbound connection on fd %d!",newsock);
684 Notifier* n = new Notifier(this->Instance, newsock, ip);
685 n = n; /* Stop bitching at me, GCC */
689 virtual bool OnDataReady()
691 Instance->Log(DEBUG,"Inbound data!");
692 char* data = this->Read();
693 ConnMap::iterator iter;
697 Instance->Log(DEBUG,"Looking for connection %s",data);
698 /* We expect to be sent a null terminated string */
699 if((iter = Connections.find(data)) != Connections.end())
701 Instance->Log(DEBUG,"Found it!");
703 /* Lock the mutex, send back the data */
704 pthread_mutex_lock(&results_mutex);
705 ResultQueue::iterator n = iter->second->rq.begin();
707 iter->second->rq.pop_front();
708 pthread_mutex_unlock(&results_mutex);
719 class ModuleSQL : public Module
724 InspIRCd* PublicServerInstance;
725 pthread_t Dispatcher;
728 void Implements(char* List)
730 List[I_OnRehash] = List[I_OnRequest] = 1;
733 unsigned long NewID()
740 char* OnRequest(Request* request)
742 if(strcmp(SQLREQID, request->GetId()) == 0)
744 SQLrequest* req = (SQLrequest*)request;
747 pthread_mutex_lock(&queue_mutex);
749 ConnMap::iterator iter;
751 char* returnval = NULL;
753 ServerInstance->Log(DEBUG, "Got query: '%s' with %d replacement parameters on id '%s'", req->query.q.c_str(), req->query.p.size(), req->dbid.c_str());
755 if((iter = Connections.find(req->dbid)) != Connections.end())
758 iter->second->queue.push(*req);
759 returnval = SQLSUCCESS;
763 req->error.Id(BAD_DBID);
766 pthread_mutex_unlock(&queue_mutex);
772 ServerInstance->Log(DEBUG, "Got unsupported API version string: %s", request->GetId());
777 ModuleSQL(InspIRCd* Me)
781 Conf = new ConfigReader(ServerInstance);
782 PublicServerInstance = ServerInstance;
786 MessagePipe = new Notifier(ServerInstance);
787 ServerInstance->Log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
789 pthread_attr_t attribs;
790 pthread_attr_init(&attribs);
791 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
792 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
794 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
796 if (!ServerInstance->PublishFeature("SQL", this))
798 /* Tell worker thread to exit NOW */
800 throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
809 virtual void OnRehash(const std::string ¶meter)
811 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
814 virtual Version GetVersion()
816 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION);
821 void* DispatcherThread(void* arg)
823 ModuleSQL* thismodule = (ModuleSQL*)arg;
824 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
826 /* Connect back to the Notifier */
828 if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
830 /* crap, we're out of sockets... */
837 insp_aton("::1", &addr.sin6_addr);
838 addr.sin6_family = AF_FAMILY;
839 addr.sin6_port = htons(MessagePipe->GetPort());
842 insp_aton("127.0.0.1", &ia);
843 addr.sin_family = AF_FAMILY;
845 addr.sin_port = htons(MessagePipe->GetPort());
848 if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
850 /* wtf, we cant connect to it, but we just created it! */
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);
889 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
891 class ModuleSQLFactory : public ModuleFactory
902 virtual Module * CreateModule(InspIRCd* Me)
904 return new ModuleSQL(Me);
910 extern "C" void * init_module( void )
912 return new ModuleSQLFactory;