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 * ---------------------------------------------------
26 #include "helperfuncs.h"
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 ../mysql_rpath.pl` */
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
74 extern InspIRCd* ServerInstance;
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 class QueryQueue : public classbase
91 typedef std::deque<SQLrequest> ReqDeque;
93 ReqDeque priority; /* The priority queue */
94 ReqDeque normal; /* The 'normal' queue */
95 enum { PRI, NOR, NON } which; /* Which queue the currently active element is at the front of */
103 void push(const SQLrequest &q)
105 log(DEBUG, "QueryQueue::push(): Adding %s query to queue: %s", ((q.pri) ? "priority" : "non-priority"), q.query.q.c_str());
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 class MySQLresult : public SQLresult
206 //std::vector<std::map<std::string,std::string> > results;
207 std::vector<std::string> colnames;
208 std::vector<SQLfieldList> fieldlists;
209 SQLfieldMap* fieldmap;
214 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows) : SQLresult(self, to), currentrow(0), fieldmap(NULL)
216 /* A number of affected rows from from mysql_affected_rows.
218 log(DEBUG,"Created new MySQLresult of non-error type");
221 if (affected_rows >= 1)
223 rows = affected_rows;
224 fieldlists.resize(rows);
226 unsigned int field_count;
231 while ((row = mysql_fetch_row(res)))
233 if (fieldlists.size() < (unsigned int)rows+1)
235 fieldlists.resize(fieldlists.size()+1);
238 MYSQL_FIELD *fields = mysql_fetch_fields(res);
239 if(mysql_num_fields(res) == 0)
241 if (fields && mysql_num_fields(res))
244 while (field_count < mysql_num_fields(res))
246 std::string a = (fields[field_count].name ? fields[field_count].name : "");
247 std::string b = (row[field_count] ? row[field_count] : "");
248 SQLfield sqlf(b, !row[field_count]);
249 colnames.push_back(a);
250 fieldlists[n].push_back(sqlf);
257 cols = mysql_num_fields(res);
258 mysql_free_result(res);
261 log(DEBUG, "Created new MySQL result; %d rows, %d columns", rows, cols);
264 MySQLresult(Module* self, Module* to, SQLerror e) : SQLresult(self, to), currentrow(0)
269 log(DEBUG,"Created new MySQLresult of error type");
286 virtual std::string ColName(int column)
288 if (column < (int)colnames.size())
290 return colnames[column];
294 throw SQLbadColName();
299 virtual int ColNum(const std::string &column)
301 for (unsigned int i = 0; i < colnames.size(); i++)
303 if (column == colnames[i])
306 throw SQLbadColName();
310 virtual SQLfield GetValue(int row, int column)
312 if ((row >= 0) && (row < rows) && (column >= 0) && (column < cols))
314 return fieldlists[row][column];
317 log(DEBUG,"Danger will robinson, we don't have row %d, column %d!", row, column);
318 throw SQLbadColName();
320 /* XXX: We never actually get here because of the throw */
321 return SQLfield("",true);
324 virtual SQLfieldList& GetRow()
326 return fieldlists[currentrow];
329 virtual SQLfieldMap& GetRowMap()
331 fieldmap = new SQLfieldMap();
333 for (int i = 0; i < cols; i++)
335 fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
342 virtual SQLfieldList* GetRowPtr()
344 return &fieldlists[currentrow++];
347 virtual SQLfieldMap* GetRowMapPtr()
349 fieldmap = new SQLfieldMap();
351 for (int i = 0; i < cols; i++)
353 fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
360 virtual void Free(SQLfieldMap* fm)
365 virtual void Free(SQLfieldList* fl)
367 /* XXX: Yes, this is SUPPOSED to do nothing, we
368 * dont want to free our fieldlist until we
369 * destruct the object. Unlike the pgsql module,
370 * we only have the one.
377 void NotifyMainThread(SQLConnection* connection_with_new_result);
379 class SQLConnection : public classbase
390 std::map<std::string,std::string> thisrow;
399 // This constructor creates an SQLConnection object with the given credentials, and creates the underlying
400 // MYSQL struct, but does not connect yet.
401 SQLConnection(std::string thishost, std::string thisuser, std::string thispass, std::string thisdb, const std::string &myid)
403 this->Enabled = true;
404 this->host = thishost;
405 this->user = thisuser;
406 this->pass = thispass;
411 // This method connects to the database using the credentials supplied to the constructor, and returns
412 // true upon success.
415 unsigned int timeout = 1;
416 mysql_init(&connection);
417 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
418 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
421 void DoLeadingQuery()
423 /* Parse the command string and dispatch it to mysql */
424 SQLrequest& req = queue.front();
425 log(DEBUG,"DO QUERY: %s",req.query.q.c_str());
427 /* Pointer to the buffer we screw around with substitution in */
430 /* Pointer to the current end of query, where we append new stuff */
433 /* Total length of the unescaped parameters */
434 unsigned long paramlen;
436 /* Total length of query, used for binary-safety in mysql_real_query */
437 unsigned long querylength = 0;
441 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
443 paramlen += i->size();
446 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
447 * sizeofquery + (totalparamlength*2) + 1
449 * The +1 is for null-terminating the string for mysql_real_escape_string
452 query = new char[req.query.q.length() + (paramlen*2)];
455 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
456 * the parameters into it...
459 for(unsigned long i = 0; i < req.query.q.length(); i++)
461 if(req.query.q[i] == '?')
463 /* We found a place to substitute..what fun.
464 * use mysql calls to escape and write the
465 * escaped string onto the end of our query buffer,
466 * then we "just" need to make sure queryend is
467 * pointing at the right place.
469 if(req.query.p.size())
471 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
474 req.query.p.pop_front();
478 log(DEBUG, "Found a substitution location but no parameter to substitute :|");
484 *queryend = req.query.q[i];
492 log(DEBUG, "Attempting to dispatch query: %s", query);
494 pthread_mutex_lock(&queue_mutex);
496 pthread_mutex_unlock(&queue_mutex);
498 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
500 /* Successfull query */
501 res = mysql_use_result(&connection);
502 unsigned long rows = mysql_affected_rows(&connection);
503 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows);
504 r->dbid = this->GetID();
505 r->query = req.query.q;
506 /* Put this new result onto the results queue.
507 * XXX: Remember to mutex the queue!
509 pthread_mutex_lock(&results_mutex);
511 pthread_mutex_unlock(&results_mutex);
515 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
516 * possible error numbers and error messages */
517 log(DEBUG,"SQL ERROR: %s",mysql_error(&connection));
518 SQLerror e((SQLerrorNum)mysql_errno(&connection), mysql_error(&connection));
519 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e);
520 r->dbid = this->GetID();
521 r->query = req.query.q;
523 pthread_mutex_lock(&results_mutex);
525 pthread_mutex_unlock(&results_mutex);
528 /* Now signal the main thread that we've got a result to process.
529 * Pass them this connection id as what to examine
532 NotifyMainThread(this);
535 bool ConnectionLost()
538 return (mysql_ping(&connection) != 0);
543 bool CheckConnection()
545 if (ConnectionLost()) {
551 std::string GetError()
553 return mysql_error(&connection);
556 const std::string& GetID()
561 std::string GetHost()
566 void SetEnable(bool Enable)
580 void ConnectDatabases(Server* Srv)
582 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
584 i->second->SetEnable(true);
585 if (i->second->Connect())
587 Srv->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
591 Srv->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
592 i->second->SetEnable(false);
598 void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
600 Srv->Log(DEFAULT,"SQL: Loading database settings");
602 Srv->Log(DEBUG,"Cleared connections");
603 for (int j =0; j < ThisConf->Enumerate("database"); j++)
605 std::string db = ThisConf->ReadValue("database","name",j);
606 std::string user = ThisConf->ReadValue("database","username",j);
607 std::string pass = ThisConf->ReadValue("database","password",j);
608 std::string host = ThisConf->ReadValue("database","hostname",j);
609 std::string id = ThisConf->ReadValue("database","id",j);
610 Srv->Log(DEBUG,"Read database settings");
611 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
613 SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
614 Srv->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
615 Connections[id] = ThisSQL;
616 Srv->Log(DEBUG,"Pushed back connection");
619 ConnectDatabases(Srv);
622 void NotifyMainThread(SQLConnection* connection_with_new_result)
624 /* Here we write() to the socket the main thread has open
625 * and we connect()ed back to before our thread became active.
626 * The main thread is using a nonblocking socket tied into
627 * the socket engine, so they wont block and they'll receive
628 * nearly instant notification. Because we're in a seperate
629 * thread, we can just use standard connect(), and we can
630 * block if we like. We just send the connection id of the
633 log(DEBUG,"Notify of result on connection: %s",connection_with_new_result->GetID().c_str());
634 if (send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0) < 1) // add one for null terminator
636 log(DEBUG,"Error writing to QueueFD: %s",strerror(errno));
638 log(DEBUG,"Sent it on its way via fd=%d",QueueFD);
641 void* DispatcherThread(void* arg);
643 class Notifier : public InspSocket
651 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
652 Notifier(Server* S) : InspSocket("127.0.0.1", 0, true, 3000), Srv(S)
654 uslen = sizeof(sock_us);
655 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
657 throw ModuleException("Could not create random listening port on localhost");
661 Notifier(int newfd, char* ip, Server* S) : InspSocket(newfd, ip), Srv(S)
663 log(DEBUG,"Constructor of new socket");
666 /* Using getsockname and ntohs, we can determine which port number we were allocated */
669 return ntohs(sock_us.sin_port);
672 virtual int OnIncomingConnection(int newsock, char* ip)
674 log(DEBUG,"Inbound connection on fd %d!",newsock);
675 Notifier* n = new Notifier(newsock, ip, Srv);
680 virtual bool OnDataReady()
682 log(DEBUG,"Inbound data!");
683 char* data = this->Read();
684 ConnMap::iterator iter;
688 log(DEBUG,"Looking for connection %s",data);
689 /* We expect to be sent a null terminated string */
690 if((iter = Connections.find(data)) != Connections.end())
692 log(DEBUG,"Found it!");
694 /* Lock the mutex, send back the data */
695 pthread_mutex_lock(&results_mutex);
696 ResultQueue::iterator n = iter->second->rq.begin();
698 iter->second->rq.pop_front();
699 pthread_mutex_unlock(&results_mutex);
708 class ModuleSQL : public Module
713 pthread_t Dispatcher;
716 void Implements(char* List)
718 List[I_OnRehash] = List[I_OnRequest] = 1;
721 unsigned long NewID()
728 char* OnRequest(Request* request)
730 if(strcmp(SQLREQID, request->GetData()) == 0)
732 SQLrequest* req = (SQLrequest*)request;
735 pthread_mutex_lock(&queue_mutex);
737 ConnMap::iterator iter;
739 char* returnval = NULL;
741 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());
743 if((iter = Connections.find(req->dbid)) != Connections.end())
745 iter->second->queue.push(*req);
747 returnval = SQLSUCCESS;
751 req->error.Id(BAD_DBID);
754 pthread_mutex_unlock(&queue_mutex);
760 log(DEBUG, "Got unsupported API version string: %s", request->GetData());
765 ModuleSQL(Server* Me)
769 Conf = new ConfigReader();
773 MessagePipe = new Notifier(Srv);
774 Srv->AddSocket(MessagePipe);
775 log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
777 pthread_attr_t attribs;
778 pthread_attr_init(&attribs);
779 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
780 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
782 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
784 Srv->PublishFeature("SQL", this);
785 Srv->PublishFeature("MySQL", this);
793 virtual void OnRehash(const std::string ¶meter)
795 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
798 virtual Version GetVersion()
800 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
805 void* DispatcherThread(void* arg)
807 log(DEBUG,"Starting Dispatcher thread, mysql version %d",mysql_get_client_version());
808 ModuleSQL* thismodule = (ModuleSQL*)arg;
809 LoadDatabases(thismodule->Conf, thismodule->Srv);
811 /* Connect back to the Notifier */
813 if ((QueueFD = socket(AF_INET, SOCK_STREAM, 0)) == -1)
815 /* crap, we're out of sockets... */
816 log(DEBUG,"QueueFD cant be created");
820 log(DEBUG,"Initialize QueueFD to %d",QueueFD);
824 inet_aton("127.0.0.1", &ia);
825 addr.sin_family = AF_INET;
827 addr.sin_port = htons(MessagePipe->GetPort());
829 if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
831 /* wtf, we cant connect to it, but we just created it! */
832 log(DEBUG,"QueueFD cant connect!");
836 log(DEBUG,"Connect QUEUE FD");
840 SQLConnection* conn = NULL;
841 /* XXX: Lock here for safety */
842 pthread_mutex_lock(&queue_mutex);
843 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
845 if (i->second->queue.totalsize())
851 pthread_mutex_unlock(&queue_mutex);
854 /* Theres an item! */
857 log(DEBUG,"Process Leading query");
858 conn->DoLeadingQuery();
861 pthread_mutex_lock(&queue_mutex);
863 pthread_mutex_unlock(&queue_mutex);
874 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
876 class ModuleSQLFactory : public ModuleFactory
887 virtual Module * CreateModule(Server* Me)
889 return new ModuleSQL(Me);
895 extern "C" void * init_module( void )
897 return new ModuleSQLFactory;