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` */
35 /* THE NONBLOCKING MYSQL API!
37 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
38 * that instead, you should thread your program. This is what i've done here to allow for
39 * asyncronous SQL requests via mysql. The way this works is as follows:
41 * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
42 * using a queue with priorities. There is a mutex on either end which prevents two threads
43 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
44 * worker thread wakes up, and checks if there is a request at the head of its queue.
45 * If there is, it processes this request, blocking the worker thread but leaving the ircd
46 * thread to go about its business as usual. During this period, the ircd thread is able
47 * to insert futher pending requests into the queue.
49 * Once the processing of a request is complete, it is removed from the incoming queue to
50 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
51 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
52 * connection ID through the connection.
54 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
55 * of the queue, and sends it on its way to the original calling module.
57 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
58 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
59 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
60 * however, if we were to call a module's OnRequest even from within a thread which was not the
61 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
62 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
63 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
64 * gauranteed threadsafe!)
66 * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
74 typedef std::map<std::string, SQLConnection*> ConnMap;
76 static Module* SQLModule = NULL;
77 static Notifier* MessagePipe = NULL;
81 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
82 #define mysql_field_count mysql_num_fields
85 typedef std::deque<SQLresult*> ResultQueue;
87 /** Represents a mysql query queue
89 class QueryQueue : public classbase
92 typedef std::deque<SQLrequest> ReqDeque;
94 ReqDeque priority; /* The priority queue */
95 ReqDeque normal; /* The 'normal' queue */
96 enum { PRI, NOR, NON } which; /* Which queue the currently active element is at the front of */
104 void push(const SQLrequest &q)
107 priority.push_back(q);
114 if((which == PRI) && priority.size())
116 priority.pop_front();
118 else if((which == NOR) && normal.size())
126 /* Silently do nothing if there was no element to pop() */
134 return priority.front();
136 return normal.front();
141 return priority.front();
147 return normal.front();
150 /* This will probably result in a segfault,
151 * but the caller should have checked totalsize()
152 * first so..meh - moron :p
155 return priority.front();
159 std::pair<int, int> size()
161 return std::make_pair(priority.size(), normal.size());
166 return priority.size() + normal.size();
169 void PurgeModule(Module* mod)
171 DoPurgeModule(mod, priority);
172 DoPurgeModule(mod, normal);
176 void DoPurgeModule(Module* mod, ReqDeque& q)
178 for(ReqDeque::iterator iter = q.begin(); iter != q.end(); iter++)
180 if(iter->GetSource() == mod)
182 if(iter->id == front().id)
184 /* It's the currently active query.. :x */
185 iter->SetSource(NULL);
189 /* It hasn't been executed yet..just remove it */
190 iter = q.erase(iter);
197 /* A mutex to wrap around queue accesses */
198 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
200 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
202 /** Represents a mysql result set
204 class MySQLresult : public SQLresult
207 //std::vector<std::map<std::string,std::string> > results;
208 std::vector<std::string> colnames;
209 std::vector<SQLfieldList> fieldlists;
210 SQLfieldMap* fieldmap;
211 SQLfieldMap fieldmap2;
212 SQLfieldList emptyfieldlist;
216 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
218 /* A number of affected rows from from mysql_affected_rows.
222 if (affected_rows >= 1)
224 rows = affected_rows;
225 fieldlists.resize(rows);
227 unsigned int field_count = 0;
232 while ((row = mysql_fetch_row(res)))
234 if (fieldlists.size() < (unsigned int)rows+1)
236 fieldlists.resize(fieldlists.size()+1);
239 MYSQL_FIELD *fields = mysql_fetch_fields(res);
240 if(mysql_num_fields(res) == 0)
242 if (fields && mysql_num_fields(res))
245 while (field_count < mysql_num_fields(res))
247 std::string a = (fields[field_count].name ? fields[field_count].name : "");
248 std::string b = (row[field_count] ? row[field_count] : "");
249 SQLfield sqlf(b, !row[field_count]);
250 colnames.push_back(a);
251 fieldlists[n].push_back(sqlf);
258 mysql_free_result(res);
262 MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
279 return colnames.size();
282 virtual std::string ColName(int column)
284 if (column < (int)colnames.size())
286 return colnames[column];
290 throw SQLbadColName();
295 virtual int ColNum(const std::string &column)
297 for (unsigned int i = 0; i < colnames.size(); i++)
299 if (column == colnames[i])
302 throw SQLbadColName();
306 virtual SQLfield GetValue(int row, int column)
308 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
310 return fieldlists[row][column];
313 throw SQLbadColName();
315 /* XXX: We never actually get here because of the throw */
316 return SQLfield("",true);
319 virtual SQLfieldList& GetRow()
321 if (currentrow < rows)
322 return fieldlists[currentrow];
324 return emptyfieldlist;
327 virtual SQLfieldMap& GetRowMap()
331 if (currentrow < rows)
333 for (int i = 0; i < Cols(); i++)
335 fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
343 virtual SQLfieldList* GetRowPtr()
345 SQLfieldList* fieldlist = new SQLfieldList();
347 if (currentrow < rows)
349 for (int i = 0; i < Rows(); i++)
351 fieldlist->push_back(fieldlists[currentrow][i]);
358 virtual SQLfieldMap* GetRowMapPtr()
360 fieldmap = new SQLfieldMap();
362 if (currentrow < rows)
364 for (int i = 0; i < Cols(); i++)
366 fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
374 virtual void Free(SQLfieldMap* fm)
379 virtual void Free(SQLfieldList* fl)
387 void NotifyMainThread(SQLConnection* connection_with_new_result);
389 /** Represents a connection to a mysql database
391 class SQLConnection : public classbase
402 std::map<std::string,std::string> thisrow;
411 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
412 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)
416 // This method connects to the database using the credentials supplied to the constructor, and returns
417 // true upon success.
420 unsigned int timeout = 1;
421 mysql_init(&connection);
422 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
423 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
426 void DoLeadingQuery()
428 if (!CheckConnection())
431 /* Parse the command string and dispatch it to mysql */
432 SQLrequest& req = queue.front();
434 /* Pointer to the buffer we screw around with substitution in */
437 /* Pointer to the current end of query, where we append new stuff */
440 /* Total length of the unescaped parameters */
441 unsigned long paramlen;
443 /* Total length of query, used for binary-safety in mysql_real_query */
444 unsigned long querylength = 0;
448 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
450 paramlen += i->size();
453 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
454 * sizeofquery + (totalparamlength*2) + 1
456 * The +1 is for null-terminating the string for mysql_real_escape_string
459 query = new char[req.query.q.length() + (paramlen*2)];
462 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
463 * the parameters into it...
466 for(unsigned long i = 0; i < req.query.q.length(); i++)
468 if(req.query.q[i] == '?')
470 /* We found a place to substitute..what fun.
471 * use mysql calls to escape and write the
472 * escaped string onto the end of our query buffer,
473 * then we "just" need to make sure queryend is
474 * pointing at the right place.
476 if(req.query.p.size())
478 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
481 req.query.p.pop_front();
488 *queryend = req.query.q[i];
496 pthread_mutex_lock(&queue_mutex);
498 pthread_mutex_unlock(&queue_mutex);
500 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
502 /* Successfull query */
503 res = mysql_use_result(&connection);
504 unsigned long rows = mysql_affected_rows(&connection);
505 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
506 r->dbid = this->GetID();
507 r->query = req.query.q;
508 /* Put this new result onto the results queue.
509 * XXX: Remember to mutex the queue!
511 pthread_mutex_lock(&results_mutex);
513 pthread_mutex_unlock(&results_mutex);
517 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
518 * possible error numbers and error messages */
519 SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
520 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
521 r->dbid = this->GetID();
522 r->query = req.query.q;
524 pthread_mutex_lock(&results_mutex);
526 pthread_mutex_unlock(&results_mutex);
529 /* Now signal the main thread that we've got a result to process.
530 * Pass them this connection id as what to examine
535 NotifyMainThread(this);
538 bool ConnectionLost()
541 return (mysql_ping(&connection) != 0);
546 bool CheckConnection()
548 if (ConnectionLost()) {
554 std::string GetError()
556 return mysql_error(&connection);
559 const std::string& GetID()
564 std::string GetHost()
569 void SetEnable(bool Enable)
583 void ConnectDatabases(InspIRCd* ServerInstance)
585 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
587 i->second->SetEnable(true);
588 if (i->second->Connect())
590 ServerInstance->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
594 ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
595 i->second->SetEnable(false);
601 void LoadDatabases(ConfigReader* ThisConf, InspIRCd* ServerInstance)
603 ServerInstance->Log(DEFAULT,"SQL: Loading database settings");
605 ServerInstance->Log(DEBUG,"Cleared connections");
606 for (int j =0; j < ThisConf->Enumerate("database"); j++)
608 std::string db = ThisConf->ReadValue("database","name",j);
609 std::string user = ThisConf->ReadValue("database","username",j);
610 std::string pass = ThisConf->ReadValue("database","password",j);
611 std::string host = ThisConf->ReadValue("database","hostname",j);
612 std::string id = ThisConf->ReadValue("database","id",j);
613 ServerInstance->Log(DEBUG,"Read database settings");
614 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
616 SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
617 ServerInstance->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
618 Connections[id] = ThisSQL;
619 ServerInstance->Log(DEBUG,"Pushed back connection");
622 ConnectDatabases(ServerInstance);
625 void NotifyMainThread(SQLConnection* connection_with_new_result)
627 /* Here we write() to the socket the main thread has open
628 * and we connect()ed back to before our thread became active.
629 * The main thread is using a nonblocking socket tied into
630 * the socket engine, so they wont block and they'll receive
631 * nearly instant notification. Because we're in a seperate
632 * thread, we can just use standard connect(), and we can
633 * block if we like. We just send the connection id of the
636 send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0);
639 void* DispatcherThread(void* arg);
641 /** Used by m_mysql to notify one thread when the other has a result
643 class Notifier : public InspSocket
645 insp_sockaddr sock_us;
651 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
653 Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000)
655 Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000)
658 uslen = sizeof(sock_us);
659 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
661 throw ModuleException("Could not create random listening port on localhost");
665 Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip)
667 Instance->Log(DEBUG,"Constructor of new socket");
670 /* Using getsockname and ntohs, we can determine which port number we were allocated */
674 return ntohs(sock_us.sin6_port);
676 return ntohs(sock_us.sin_port);
680 virtual int OnIncomingConnection(int newsock, char* ip)
682 Instance->Log(DEBUG,"Inbound connection on fd %d!",newsock);
683 Notifier* n = new Notifier(this->Instance, newsock, ip);
684 n = n; /* Stop bitching at me, GCC */
688 virtual bool OnDataReady()
690 Instance->Log(DEBUG,"Inbound data!");
691 char* data = this->Read();
692 ConnMap::iterator iter;
696 Instance->Log(DEBUG,"Looking for connection %s",data);
697 /* We expect to be sent a null terminated string */
698 if((iter = Connections.find(data)) != Connections.end())
700 Instance->Log(DEBUG,"Found it!");
702 /* Lock the mutex, send back the data */
703 pthread_mutex_lock(&results_mutex);
704 ResultQueue::iterator n = iter->second->rq.begin();
706 iter->second->rq.pop_front();
707 pthread_mutex_unlock(&results_mutex);
718 class ModuleSQL : public Module
723 InspIRCd* PublicServerInstance;
724 pthread_t Dispatcher;
727 void Implements(char* List)
729 List[I_OnRehash] = List[I_OnRequest] = 1;
732 unsigned long NewID()
739 char* OnRequest(Request* request)
741 if(strcmp(SQLREQID, request->GetId()) == 0)
743 SQLrequest* req = (SQLrequest*)request;
746 pthread_mutex_lock(&queue_mutex);
748 ConnMap::iterator iter;
750 char* returnval = NULL;
752 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());
754 if((iter = Connections.find(req->dbid)) != Connections.end())
757 iter->second->queue.push(*req);
758 returnval = SQLSUCCESS;
762 req->error.Id(BAD_DBID);
765 pthread_mutex_unlock(&queue_mutex);
771 ServerInstance->Log(DEBUG, "Got unsupported API version string: %s", request->GetId());
776 ModuleSQL(InspIRCd* Me)
780 Conf = new ConfigReader(ServerInstance);
781 PublicServerInstance = ServerInstance;
785 MessagePipe = new Notifier(ServerInstance);
786 ServerInstance->Log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
788 pthread_attr_t attribs;
789 pthread_attr_init(&attribs);
790 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
791 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
793 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
795 if (!ServerInstance->PublishFeature("SQL", this))
797 /* Tell worker thread to exit NOW */
799 throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
808 virtual void OnRehash(const std::string ¶meter)
810 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
813 virtual Version GetVersion()
815 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION);
820 void* DispatcherThread(void* arg)
822 ModuleSQL* thismodule = (ModuleSQL*)arg;
823 LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
825 /* Connect back to the Notifier */
827 if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
829 /* crap, we're out of sockets... */
836 insp_aton("::1", &addr.sin6_addr);
837 addr.sin6_family = AF_FAMILY;
838 addr.sin6_port = htons(MessagePipe->GetPort());
841 insp_aton("127.0.0.1", &ia);
842 addr.sin_family = AF_FAMILY;
844 addr.sin_port = htons(MessagePipe->GetPort());
847 if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
849 /* wtf, we cant connect to it, but we just created it! */
855 SQLConnection* conn = NULL;
856 /* XXX: Lock here for safety */
857 pthread_mutex_lock(&queue_mutex);
858 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
860 if (i->second->queue.totalsize())
866 pthread_mutex_unlock(&queue_mutex);
869 /* Theres an item! */
872 conn->DoLeadingQuery();
875 pthread_mutex_lock(&queue_mutex);
877 pthread_mutex_unlock(&queue_mutex);
888 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
890 class ModuleSQLFactory : public ModuleFactory
901 virtual Module * CreateModule(InspIRCd* Me)
903 return new ModuleSQL(Me);
909 extern "C" void * init_module( void )
911 return new ModuleSQLFactory;