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` */
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
73 extern InspIRCd* ServerInstance;
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 class QueryQueue : public classbase
90 typedef std::deque<SQLrequest> ReqDeque;
92 ReqDeque priority; /* The priority queue */
93 ReqDeque normal; /* The 'normal' queue */
94 enum { PRI, NOR, NON } which; /* Which queue the currently active element is at the front of */
102 void push(const SQLrequest &q)
104 log(DEBUG, "QueryQueue::push(): Adding %s query to queue: %s", ((q.pri) ? "priority" : "non-priority"), q.query.q.c_str());
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 class MySQLresult : public SQLresult
205 //std::vector<std::map<std::string,std::string> > results;
206 std::vector<std::string> colnames;
207 std::vector<SQLfieldList> fieldlists;
208 SQLfieldMap* fieldmap;
213 MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
215 /* A number of affected rows from from mysql_affected_rows.
217 log(DEBUG,"Created new MySQLresult of non-error type");
220 if (affected_rows >= 1)
222 rows = affected_rows;
223 fieldlists.resize(rows);
225 unsigned int field_count = 0;
230 while ((row = mysql_fetch_row(res)))
232 if (fieldlists.size() < (unsigned int)rows+1)
234 fieldlists.resize(fieldlists.size()+1);
237 MYSQL_FIELD *fields = mysql_fetch_fields(res);
238 if(mysql_num_fields(res) == 0)
240 if (fields && mysql_num_fields(res))
243 while (field_count < mysql_num_fields(res))
245 std::string a = (fields[field_count].name ? fields[field_count].name : "");
246 std::string b = (row[field_count] ? row[field_count] : "");
247 SQLfield sqlf(b, !row[field_count]);
248 colnames.push_back(a);
249 fieldlists[n].push_back(sqlf);
250 log(DEBUG,"Inc field count to %d",field_count+1);
257 mysql_free_result(res);
259 log(DEBUG, "Created new MySQL result; %d rows, %d columns", rows, colnames.size());
262 MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
266 log(DEBUG,"Created new MySQLresult of error type");
275 /* An INSERT can return 0 columns, but N rows. This is unsafe to
276 * allow the user to 'see'. Go figure. I hate you, MySQL devs.
286 return colnames.size();
289 virtual std::string ColName(int column)
291 if (column < (int)colnames.size())
293 return colnames[column];
297 throw SQLbadColName();
302 virtual int ColNum(const std::string &column)
304 for (unsigned int i = 0; i < colnames.size(); i++)
306 if (column == colnames[i])
309 throw SQLbadColName();
313 virtual SQLfield GetValue(int row, int column)
315 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
317 return fieldlists[row][column];
320 log(DEBUG,"Danger will robinson, we don't have row %d, column %d!", row, column);
321 throw SQLbadColName();
323 /* XXX: We never actually get here because of the throw */
324 return SQLfield("",true);
327 virtual SQLfieldList& GetRow()
329 return fieldlists[currentrow];
332 virtual SQLfieldMap& GetRowMap()
334 fieldmap = new SQLfieldMap();
336 for (int i = 0; i < cols; i++)
338 fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
345 virtual SQLfieldList* GetRowPtr()
347 return &fieldlists[currentrow++];
350 virtual SQLfieldMap* GetRowMapPtr()
352 fieldmap = new SQLfieldMap();
354 for (int i = 0; i < cols; i++)
356 fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
363 virtual void Free(SQLfieldMap* fm)
368 virtual void Free(SQLfieldList* fl)
370 /* XXX: Yes, this is SUPPOSED to do nothing, we
371 * dont want to free our fieldlist until we
372 * destruct the object. Unlike the pgsql module,
373 * we only have the one.
380 void NotifyMainThread(SQLConnection* connection_with_new_result);
382 class SQLConnection : public classbase
393 std::map<std::string,std::string> thisrow;
402 // This constructor creates an SQLConnection object with the given credentials, and creates the underlying
403 // MYSQL struct, but does not connect yet.
404 SQLConnection(std::string thishost, std::string thisuser, std::string thispass, std::string thisdb, const std::string &myid)
406 this->Enabled = true;
407 this->host = thishost;
408 this->user = thisuser;
409 this->pass = thispass;
414 // This method connects to the database using the credentials supplied to the constructor, and returns
415 // true upon success.
418 unsigned int timeout = 1;
419 mysql_init(&connection);
420 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
421 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
424 void DoLeadingQuery()
426 if (!CheckConnection())
429 /* Parse the command string and dispatch it to mysql */
430 SQLrequest& req = queue.front();
431 log(DEBUG,"DO QUERY: %s",req.query.q.c_str());
433 /* Pointer to the buffer we screw around with substitution in */
436 /* Pointer to the current end of query, where we append new stuff */
439 /* Total length of the unescaped parameters */
440 unsigned long paramlen;
442 /* Total length of query, used for binary-safety in mysql_real_query */
443 unsigned long querylength = 0;
447 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
449 paramlen += i->size();
452 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
453 * sizeofquery + (totalparamlength*2) + 1
455 * The +1 is for null-terminating the string for mysql_real_escape_string
458 query = new char[req.query.q.length() + (paramlen*2)];
461 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
462 * the parameters into it...
465 for(unsigned long i = 0; i < req.query.q.length(); i++)
467 if(req.query.q[i] == '?')
469 /* We found a place to substitute..what fun.
470 * use mysql calls to escape and write the
471 * escaped string onto the end of our query buffer,
472 * then we "just" need to make sure queryend is
473 * pointing at the right place.
475 if(req.query.p.size())
477 unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
480 req.query.p.pop_front();
484 log(DEBUG, "Found a substitution location but no parameter to substitute :|");
490 *queryend = req.query.q[i];
498 log(DEBUG, "Attempting to dispatch query: %s", query);
500 pthread_mutex_lock(&queue_mutex);
502 pthread_mutex_unlock(&queue_mutex);
504 log(DEBUG,"REQUEST ID: %d",req.id);
506 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
508 /* Successfull query */
509 res = mysql_use_result(&connection);
510 unsigned long rows = mysql_affected_rows(&connection);
511 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
512 r->dbid = this->GetID();
513 r->query = req.query.q;
514 /* Put this new result onto the results queue.
515 * XXX: Remember to mutex the queue!
517 pthread_mutex_lock(&results_mutex);
519 pthread_mutex_unlock(&results_mutex);
523 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
524 * possible error numbers and error messages */
525 log(DEBUG,"SQL ERROR: %s",mysql_error(&connection));
526 SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
527 MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
528 r->dbid = this->GetID();
529 r->query = req.query.q;
531 pthread_mutex_lock(&results_mutex);
533 pthread_mutex_unlock(&results_mutex);
536 /* Now signal the main thread that we've got a result to process.
537 * Pass them this connection id as what to examine
540 NotifyMainThread(this);
543 bool ConnectionLost()
546 return (mysql_ping(&connection) != 0);
551 bool CheckConnection()
553 if (ConnectionLost()) {
559 std::string GetError()
561 return mysql_error(&connection);
564 const std::string& GetID()
569 std::string GetHost()
574 void SetEnable(bool Enable)
588 void ConnectDatabases(Server* Srv)
590 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
592 i->second->SetEnable(true);
593 if (i->second->Connect())
595 Srv->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
599 Srv->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
600 i->second->SetEnable(false);
606 void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
608 Srv->Log(DEFAULT,"SQL: Loading database settings");
610 Srv->Log(DEBUG,"Cleared connections");
611 for (int j =0; j < ThisConf->Enumerate("database"); j++)
613 std::string db = ThisConf->ReadValue("database","name",j);
614 std::string user = ThisConf->ReadValue("database","username",j);
615 std::string pass = ThisConf->ReadValue("database","password",j);
616 std::string host = ThisConf->ReadValue("database","hostname",j);
617 std::string id = ThisConf->ReadValue("database","id",j);
618 Srv->Log(DEBUG,"Read database settings");
619 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
621 SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
622 Srv->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
623 Connections[id] = ThisSQL;
624 Srv->Log(DEBUG,"Pushed back connection");
627 ConnectDatabases(Srv);
630 void NotifyMainThread(SQLConnection* connection_with_new_result)
632 /* Here we write() to the socket the main thread has open
633 * and we connect()ed back to before our thread became active.
634 * The main thread is using a nonblocking socket tied into
635 * the socket engine, so they wont block and they'll receive
636 * nearly instant notification. Because we're in a seperate
637 * thread, we can just use standard connect(), and we can
638 * block if we like. We just send the connection id of the
641 log(DEBUG,"Notify of result on connection: %s",connection_with_new_result->GetID().c_str());
642 if (send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0) < 1) // add one for null terminator
644 log(DEBUG,"Error writing to QueueFD: %s",strerror(errno));
646 log(DEBUG,"Sent it on its way via fd=%d",QueueFD);
649 void* DispatcherThread(void* arg);
651 class Notifier : public InspSocket
659 /* Create a socket on a random port. Let the tcp stack allocate us an available port */
660 Notifier(Server* S) : InspSocket("127.0.0.1", 0, true, 3000), Srv(S)
662 uslen = sizeof(sock_us);
663 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
665 throw ModuleException("Could not create random listening port on localhost");
669 Notifier(int newfd, char* ip, Server* S) : InspSocket(newfd, ip), Srv(S)
671 log(DEBUG,"Constructor of new socket");
674 /* Using getsockname and ntohs, we can determine which port number we were allocated */
677 return ntohs(sock_us.sin_port);
680 virtual int OnIncomingConnection(int newsock, char* ip)
682 log(DEBUG,"Inbound connection on fd %d!",newsock);
683 Notifier* n = new Notifier(newsock, ip, Srv);
688 virtual bool OnDataReady()
690 log(DEBUG,"Inbound data!");
691 char* data = this->Read();
692 ConnMap::iterator iter;
696 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 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);
716 class ModuleSQL : public Module
721 pthread_t Dispatcher;
724 void Implements(char* List)
726 List[I_OnRehash] = List[I_OnRequest] = 1;
729 unsigned long NewID()
736 char* OnRequest(Request* request)
738 if(strcmp(SQLREQID, request->GetData()) == 0)
740 SQLrequest* req = (SQLrequest*)request;
743 pthread_mutex_lock(&queue_mutex);
745 ConnMap::iterator iter;
747 char* returnval = NULL;
749 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());
751 if((iter = Connections.find(req->dbid)) != Connections.end())
754 iter->second->queue.push(*req);
755 returnval = SQLSUCCESS;
759 req->error.Id(BAD_DBID);
762 pthread_mutex_unlock(&queue_mutex);
768 log(DEBUG, "Got unsupported API version string: %s", request->GetData());
773 ModuleSQL(Server* Me)
777 Conf = new ConfigReader();
781 MessagePipe = new Notifier(Srv);
782 Srv->AddSocket(MessagePipe);
783 log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
785 pthread_attr_t attribs;
786 pthread_attr_init(&attribs);
787 pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
788 if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
790 throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
792 if (!Srv->PublishFeature("SQL", this))
794 /* Tell worker thread to exit NOW */
796 throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
805 virtual void OnRehash(const std::string ¶meter)
807 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
810 virtual Version GetVersion()
812 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
817 void* DispatcherThread(void* arg)
819 log(DEBUG,"Starting Dispatcher thread, mysql version %d",mysql_get_client_version());
820 ModuleSQL* thismodule = (ModuleSQL*)arg;
821 LoadDatabases(thismodule->Conf, thismodule->Srv);
823 /* Connect back to the Notifier */
825 if ((QueueFD = socket(AF_INET, SOCK_STREAM, 0)) == -1)
827 /* crap, we're out of sockets... */
828 log(DEBUG,"QueueFD cant be created");
832 log(DEBUG,"Initialize QueueFD to %d",QueueFD);
836 inet_aton("127.0.0.1", &ia);
837 addr.sin_family = AF_INET;
839 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! */
844 log(DEBUG,"QueueFD cant connect!");
848 log(DEBUG,"Connect QUEUE FD");
852 SQLConnection* conn = NULL;
853 /* XXX: Lock here for safety */
854 pthread_mutex_lock(&queue_mutex);
855 for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
857 if (i->second->queue.totalsize())
863 pthread_mutex_unlock(&queue_mutex);
866 /* Theres an item! */
869 log(DEBUG,"Process Leading query");
870 conn->DoLeadingQuery();
873 pthread_mutex_lock(&queue_mutex);
875 pthread_mutex_unlock(&queue_mutex);
886 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
888 class ModuleSQLFactory : public ModuleFactory
899 virtual Module * CreateModule(Server* Me)
901 return new ModuleSQL(Me);
907 extern "C" void * init_module( void )
909 return new ModuleSQLFactory;