src/modules/extra/m_mysql.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd is copyright (C) 2002-2004 ChatSpike-Dev.
   6  *                     E-mail:
   7  *              <brain@chatspike.net>
   8  *                <Craig@chatspike.net>
   9  *
  10  * Written by Craig Edwards, Craig McLure, and others.
  11  * This program is free but copyrighted software; see
  12  *          the file COPYING for details.
  13  *
  14  * ---------------------------------------------------
  15  */
  16
  17 using namespace std;
  18
  19 #include <stdio.h>
  20 #include <string>
  21 #include <mysql.h>
  22 #include <pthread.h>
  23 #include "users.h"
  24 #include "channels.h"
  25 #include "modules.h"
  26 #include "helperfuncs.h"
  27 #include "inspircd.h"
  28 #include "m_sqlv2.h"
  29
  30 /* VERSION 2 API: With nonblocking (threaded) requests */
  31
  32 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
  33 /* $CompileFlags: `mysql_config --include` */
  34 /* $LinkerFlags: `mysql_config --libs_r` `perl extra/mysql_rpath.pl` */
  35
  36 /* THE NONBLOCKING MYSQL API!
  37  *
  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:
  41  *
  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.
  49  *
  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.
  54  *
  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.
  57  *
  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!)
  66  *
  67  * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
  68  */
  69
  70
  71 class SQLConnection;
  72 class Notifier;
  73
  74
  75 typedef std::map<std::string, SQLConnection*> ConnMap;
  76 bool giveup = false;
  77 static Module* SQLModule = NULL;
  78 static Notifier* MessagePipe = NULL;
  79 int QueueFD = -1;
  80
  81
  82 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
  83 #define mysql_field_count mysql_num_fields
  84 #endif
  85
  86 typedef std::deque<SQLresult*> ResultQueue;
  87
  88 class QueryQueue : public classbase
  89 {
  90 private:
  91         typedef std::deque<SQLrequest> ReqDeque;
  92
  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 */
  96
  97 public:
  98         QueryQueue()
  99         : which(NON)
 100         {
 101         }
 102
 103         void push(const SQLrequest &q)
 104         {
 105                 if(q.pri)
 106                         priority.push_back(q);
 107                 else
 108                         normal.push_back(q);
 109         }
 110
 111         void pop()
 112         {
 113                 if((which == PRI) && priority.size())
 114                 {
 115                         priority.pop_front();
 116                 }
 117                 else if((which == NOR) && normal.size())
 118                 {
 119                         normal.pop_front();
 120                 }
 121
 122                 /* Reset this */
 123                 which = NON;
 124
 125                 /* Silently do nothing if there was no element to pop() */
 126         }
 127
 128         SQLrequest& front()
 129         {
 130                 switch(which)
 131                 {
 132                         case PRI:
 133                                 return priority.front();
 134                         case NOR:
 135                                 return normal.front();
 136                         default:
 137                                 if(priority.size())
 138                                 {
 139                                         which = PRI;
 140                                         return priority.front();
 141                                 }
 142
 143                                 if(normal.size())
 144                                 {
 145                                         which = NOR;
 146                                         return normal.front();
 147                                 }
 148
 149                                 /* This will probably result in a segfault,
 150                                  * but the caller should have checked totalsize()
 151                                  * first so..meh - moron :p
 152                                  */
 153
 154                                 return priority.front();
 155                 }
 156         }
 157
 158         std::pair<int, int> size()
 159         {
 160                 return std::make_pair(priority.size(), normal.size());
 161         }
 162
 163         int totalsize()
 164         {
 165                 return priority.size() + normal.size();
 166         }
 167
 168         void PurgeModule(Module* mod)
 169         {
 170                 DoPurgeModule(mod, priority);
 171                 DoPurgeModule(mod, normal);
 172         }
 173
 174 private:
 175         void DoPurgeModule(Module* mod, ReqDeque& q)
 176         {
 177                 for(ReqDeque::iterator iter = q.begin(); iter != q.end(); iter++)
 178                 {
 179                         if(iter->GetSource() == mod)
 180                         {
 181                                 if(iter->id == front().id)
 182                                 {
 183                                         /* It's the currently active query.. :x */
 184                                         iter->SetSource(NULL);
 185                                 }
 186                                 else
 187                                 {
 188                                         /* It hasn't been executed yet..just remove it */
 189                                         iter = q.erase(iter);
 190                                 }
 191                         }
 192                 }
 193         }
 194 };
 195
 196 /* A mutex to wrap around queue accesses */
 197 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
 198
 199 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
 200
 201 class MySQLresult : public SQLresult
 202 {
 203         int currentrow;
 204         //std::vector<std::map<std::string,std::string> > results;
 205         std::vector<std::string> colnames;
 206         std::vector<SQLfieldList> fieldlists;
 207         SQLfieldMap* fieldmap;
 208         SQLfieldMap fieldmap2;
 209         SQLfieldList emptyfieldlist;
 210         int rows;
 211  public:
 212
 213         MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
 214         {
 215                 /* A number of affected rows from from mysql_affected_rows.
 216                  */
 217                 fieldlists.clear();
 218                 rows = 0;
 219                 if (affected_rows >= 1)
 220                 {
 221                         rows = affected_rows;
 222                         fieldlists.resize(rows);
 223                 }
 224                 unsigned int field_count = 0;
 225                 if (res)
 226                 {
 227                         MYSQL_ROW row;
 228                         int n = 0;
 229                         while ((row = mysql_fetch_row(res)))
 230                         {
 231                                 if (fieldlists.size() < (unsigned int)rows+1)
 232                                 {
 233                                         fieldlists.resize(fieldlists.size()+1);
 234                                 }
 235                                 field_count = 0;
 236                                 MYSQL_FIELD *fields = mysql_fetch_fields(res);
 237                                 if(mysql_num_fields(res) == 0)
 238                                         break;
 239                                 if (fields && mysql_num_fields(res))
 240                                 {
 241                                         colnames.clear();
 242                                         while (field_count < mysql_num_fields(res))
 243                                         {
 244                                                 std::string a = (fields[field_count].name ? fields[field_count].name : "");
 245                                                 std::string b = (row[field_count] ? row[field_count] : "");
 246                                                 SQLfield sqlf(b, !row[field_count]);
 247                                                 colnames.push_back(a);
 248                                                 fieldlists[n].push_back(sqlf);
 249                                                 field_count++;
 250                                         }
 251                                         n++;
 252                                 }
 253                                 rows++;
 254                         }
 255                         mysql_free_result(res);
 256                 }
 257         }
 258
 259         MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
 260         {
 261                 rows = 0;
 262                 error = e;
 263         }
 264
 265         ~MySQLresult()
 266         {
 267         }
 268
 269         virtual int Rows()
 270         {
 271                 return rows;
 272         }
 273
 274         virtual int Cols()
 275         {
 276                 return colnames.size();
 277         }
 278
 279         virtual std::string ColName(int column)
 280         {
 281                 if (column < (int)colnames.size())
 282                 {
 283                         return colnames[column];
 284                 }
 285                 else
 286                 {
 287                         throw SQLbadColName();
 288                 }
 289                 return "";
 290         }
 291
 292         virtual int ColNum(const std::string &column)
 293         {
 294                 for (unsigned int i = 0; i < colnames.size(); i++)
 295                 {
 296                         if (column == colnames[i])
 297                                 return i;
 298                 }
 299                 throw SQLbadColName();
 300                 return 0;
 301         }
 302
 303         virtual SQLfield GetValue(int row, int column)
 304         {
 305                 if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
 306                 {
 307                         return fieldlists[row][column];
 308                 }
 309
 310                 throw SQLbadColName();
 311
 312                 /* XXX: We never actually get here because of the throw */
 313                 return SQLfield("",true);
 314         }
 315
 316         virtual SQLfieldList& GetRow()
 317         {
 318                 if (currentrow < rows)
 319                         return fieldlists[currentrow];
 320                 else
 321                         return emptyfieldlist;
 322         }
 323
 324         virtual SQLfieldMap& GetRowMap()
 325         {
 326                 fieldmap2.clear();
 327
 328                 if (currentrow < rows)
 329                 {
 330                         for (int i = 0; i < Cols(); i++)
 331                         {
 332                                 fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
 333                         }
 334                         currentrow++;
 335                 }
 336
 337                 return fieldmap2;
 338         }
 339
 340         virtual SQLfieldList* GetRowPtr()
 341         {
 342                 SQLfieldList* fieldlist = new SQLfieldList();
 343
 344                 if (currentrow < rows)
 345                 {
 346                         for (int i = 0; i < Rows(); i++)
 347                         {
 348                                 fieldlist->push_back(fieldlists[currentrow][i]);
 349                         }
 350                         currentrow++;
 351                 }
 352                 return fieldlist;
 353         }
 354
 355         virtual SQLfieldMap* GetRowMapPtr()
 356         {
 357                 fieldmap = new SQLfieldMap();
 358
 359                 if (currentrow < rows)
 360                 {
 361                         for (int i = 0; i < Cols(); i++)
 362                         {
 363                                 fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
 364                         }
 365                         currentrow++;
 366                 }
 367
 368                 return fieldmap;
 369         }
 370
 371         virtual void Free(SQLfieldMap* fm)
 372         {
 373                 delete fm;
 374         }
 375
 376         virtual void Free(SQLfieldList* fl)
 377         {
 378                 delete fl;
 379         }
 380 };
 381
 382 class SQLConnection;
 383
 384 void NotifyMainThread(SQLConnection* connection_with_new_result);
 385
 386 class SQLConnection : public classbase
 387 {
 388  protected:
 389
 390         MYSQL connection;
 391         MYSQL_RES *res;
 392         MYSQL_ROW row;
 393         std::string host;
 394         std::string user;
 395         std::string pass;
 396         std::string db;
 397         std::map<std::string,std::string> thisrow;
 398         bool Enabled;
 399         std::string id;
 400
 401  public:
 402
 403         QueryQueue queue;
 404         ResultQueue rq;
 405
 406         // This constructor creates an SQLConnection object with the given credentials, and creates the underlying
 407         // MYSQL struct, but does not connect yet.
 408         SQLConnection(std::string thishost, std::string thisuser, std::string thispass, std::string thisdb, const std::string &myid)
 409         {
 410                 this->Enabled = true;
 411                 this->host = thishost;
 412                 this->user = thisuser;
 413                 this->pass = thispass;
 414                 this->db = thisdb;
 415                 this->id = myid;
 416         }
 417
 418         // This method connects to the database using the credentials supplied to the constructor, and returns
 419         // true upon success.
 420         bool Connect()
 421         {
 422                 unsigned int timeout = 1;
 423                 mysql_init(&connection);
 424                 mysql_options(&connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
 425                 return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
 426         }
 427
 428         void DoLeadingQuery()
 429         {
 430                 if (!CheckConnection())
 431                         return;
 432
 433                 /* Parse the command string and dispatch it to mysql */
 434                 SQLrequest& req = queue.front();
 435
 436                 /* Pointer to the buffer we screw around with substitution in */
 437                 char* query;
 438
 439                 /* Pointer to the current end of query, where we append new stuff */
 440                 char* queryend;
 441
 442                 /* Total length of the unescaped parameters */
 443                 unsigned long paramlen;
 444
 445                 /* Total length of query, used for binary-safety in mysql_real_query */
 446                 unsigned long querylength = 0;
 447
 448                 paramlen = 0;
 449
 450                 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
 451                 {
 452                         paramlen += i->size();
 453                 }
 454
 455                 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
 456                  * sizeofquery + (totalparamlength*2) + 1
 457                  *
 458                  * The +1 is for null-terminating the string for mysql_real_escape_string
 459                  */
 460
 461                 query = new char[req.query.q.length() + (paramlen*2)];
 462                 queryend = query;
 463
 464                 /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
 465                  * the parameters into it...
 466                  */
 467
 468                 for(unsigned long i = 0; i < req.query.q.length(); i++)
 469                 {
 470                         if(req.query.q[i] == '?')
 471                         {
 472                                 /* We found a place to substitute..what fun.
 473                                  * use mysql calls to escape and write the
 474                                  * escaped string onto the end of our query buffer,
 475                                  * then we "just" need to make sure queryend is
 476                                  * pointing at the right place.
 477                                  */
 478                                 if(req.query.p.size())
 479                                 {
 480                                         unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
 481
 482                                         queryend += len;
 483                                         req.query.p.pop_front();
 484                                 }
 485                                 else
 486                                         break;
 487                         }
 488                         else
 489                         {
 490                                 *queryend = req.query.q[i];
 491                                 queryend++;
 492                         }
 493                         querylength++;
 494                 }
 495
 496                 *queryend = 0;
 497
 498                 pthread_mutex_lock(&queue_mutex);
 499                 req.query.q = query;
 500                 pthread_mutex_unlock(&queue_mutex);
 501
 502                 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
 503                 {
 504                         /* Successfull query */
 505                         res = mysql_use_result(&connection);
 506                         unsigned long rows = mysql_affected_rows(&connection);
 507                         MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
 508                         r->dbid = this->GetID();
 509                         r->query = req.query.q;
 510                         /* Put this new result onto the results queue.
 511                          * XXX: Remember to mutex the queue!
 512                          */
 513                         pthread_mutex_lock(&results_mutex);
 514                         rq.push_back(r);
 515                         pthread_mutex_unlock(&results_mutex);
 516                 }
 517                 else
 518                 {
 519                         /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
 520                          * possible error numbers and error messages */
 521                         SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
 522                         MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
 523                         r->dbid = this->GetID();
 524                         r->query = req.query.q;
 525
 526                         pthread_mutex_lock(&results_mutex);
 527                         rq.push_back(r);
 528                         pthread_mutex_unlock(&results_mutex);
 529                 }
 530
 531                 /* Now signal the main thread that we've got a result to process.
 532                  * Pass them this connection id as what to examine
 533                  */
 534
 535                 NotifyMainThread(this);
 536         }
 537
 538         bool ConnectionLost()
 539         {
 540                 if (&connection) {
 541                         return (mysql_ping(&connection) != 0);
 542                 }
 543                 else return false;
 544         }
 545
 546         bool CheckConnection()
 547         {
 548                 if (ConnectionLost()) {
 549                         return Connect();
 550                 }
 551                 else return true;
 552         }
 553
 554         std::string GetError()
 555         {
 556                 return mysql_error(&connection);
 557         }
 558
 559         const std::string& GetID()
 560         {
 561                 return id;
 562         }
 563
 564         std::string GetHost()
 565         {
 566                 return host;
 567         }
 568
 569         void SetEnable(bool Enable)
 570         {
 571                 Enabled = Enable;
 572         }
 573
 574         bool IsEnabled()
 575         {
 576                 return Enabled;
 577         }
 578
 579 };
 580
 581 ConnMap Connections;
 582
 583 void ConnectDatabases(InspIRCd* ServerInstance)
 584 {
 585         for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
 586         {
 587                 i->second->SetEnable(true);
 588                 if (i->second->Connect())
 589                 {
 590                         log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
 591                 }
 592                 else
 593                 {
 594                         log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
 595                         i->second->SetEnable(false);
 596                 }
 597         }
 598 }
 599
 600
 601 void LoadDatabases(ConfigReader* ThisConf, InspIRCd* ServerInstance)
 602 {
 603         log(DEFAULT,"SQL: Loading database settings");
 604         Connections.clear();
 605         log(DEBUG,"Cleared connections");
 606         for (int j =0; j < ThisConf->Enumerate("database"); j++)
 607         {
 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                 log(DEBUG,"Read database settings");
 614                 if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
 615                 {
 616                         SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
 617                         log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
 618                         Connections[id] = ThisSQL;
 619                         log(DEBUG,"Pushed back connection");
 620                 }
 621         }
 622         ConnectDatabases(ServerInstance);
 623 }
 624
 625 void NotifyMainThread(SQLConnection* connection_with_new_result)
 626 {
 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
 634          * connection back.
 635          */
 636         send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0);
 637 }
 638
 639 void* DispatcherThread(void* arg);
 640
 641 class Notifier : public InspSocket
 642 {
 643         insp_sockaddr sock_us;
 644         socklen_t uslen;
 645
 646
 647  public:
 648
 649         /* Create a socket on a random port. Let the tcp stack allocate us an available port */
 650 #ifdef IPV6
 651         Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000)
 652 #else
 653         Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000)
 654 #endif
 655         {
 656                 uslen = sizeof(sock_us);
 657                 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
 658                 {
 659                         throw ModuleException("Could not create random listening port on localhost");
 660                 }
 661         }
 662
 663         Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip)
 664         {
 665                 ilog(Instance,DEBUG,"Constructor of new socket");
 666         }
 667
 668         /* Using getsockname and ntohs, we can determine which port number we were allocated */
 669         int GetPort()
 670         {
 671 #ifdef IPV6
 672                 return ntohs(sock_us.sin6_port);
 673 #else
 674                 return ntohs(sock_us.sin_port);
 675 #endif
 676         }
 677
 678         virtual int OnIncomingConnection(int newsock, char* ip)
 679         {
 680                 ilog(Instance,DEBUG,"Inbound connection on fd %d!",newsock);
 681                 Notifier* n = new Notifier(this->Instance, newsock, ip);
 682                 this->Instance->AddSocket(n);
 683                 return true;
 684         }
 685
 686         virtual bool OnDataReady()
 687         {
 688                 ilog(Instance,DEBUG,"Inbound data!");
 689                 char* data = this->Read();
 690                 ConnMap::iterator iter;
 691
 692                 if (data && *data)
 693                 {
 694                         ilog(Instance,DEBUG,"Looking for connection %s",data);
 695                         /* We expect to be sent a null terminated string */
 696                         if((iter = Connections.find(data)) != Connections.end())
 697                         {
 698                                 ilog(Instance,DEBUG,"Found it!");
 699
 700                                 /* Lock the mutex, send back the data */
 701                                 pthread_mutex_lock(&results_mutex);
 702                                 ResultQueue::iterator n = iter->second->rq.begin();
 703                                 (*n)->Send();
 704                                 iter->second->rq.pop_front();
 705                                 pthread_mutex_unlock(&results_mutex);
 706                                 return true;
 707                         }
 708                 }
 709
 710                 return false;
 711         }
 712 };
 713
 714 class ModuleSQL : public Module
 715 {
 716  public:
 717
 718         ConfigReader *Conf;
 719         InspIRCd* PublicServerInstance;
 720         pthread_t Dispatcher;
 721         int currid;
 722
 723         void Implements(char* List)
 724         {
 725                 List[I_OnRehash] = List[I_OnRequest] = 1;
 726         }
 727
 728         unsigned long NewID()
 729         {
 730                 if (currid+1 == 0)
 731                         currid++;
 732                 return ++currid;
 733         }
 734
 735         char* OnRequest(Request* request)
 736         {
 737                 if(strcmp(SQLREQID, request->GetId()) == 0)
 738                 {
 739                         SQLrequest* req = (SQLrequest*)request;
 740
 741                         /* XXX: Lock */
 742                         pthread_mutex_lock(&queue_mutex);
 743
 744                         ConnMap::iterator iter;
 745
 746                         char* returnval = NULL;
 747
 748                         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());
 749
 750                         if((iter = Connections.find(req->dbid)) != Connections.end())
 751                         {
 752                                 req->id = NewID();
 753                                 iter->second->queue.push(*req);
 754                                 returnval = SQLSUCCESS;
 755                         }
 756                         else
 757                         {
 758                                 req->error.Id(BAD_DBID);
 759                         }
 760
 761                         pthread_mutex_unlock(&queue_mutex);
 762                         /* XXX: Unlock */
 763
 764                         return returnval;
 765                 }
 766
 767                 log(DEBUG, "Got unsupported API version string: %s", request->GetId());
 768
 769                 return NULL;
 770         }
 771
 772         ModuleSQL(InspIRCd* Me)
 773                 : Module::Module(Me)
 774         {
 775
 776                 Conf = new ConfigReader(ServerInstance);
 777                 PublicServerInstance = ServerInstance;
 778                 currid = 0;
 779                 SQLModule = this;
 780
 781                 MessagePipe = new Notifier(ServerInstance);
 782                 ServerInstance->AddSocket(MessagePipe);
 783                 log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
 784
 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)
 789                 {
 790                         throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
 791                 }
 792                 if (!ServerInstance->PublishFeature("SQL", this))
 793                 {
 794                         /* Tell worker thread to exit NOW */
 795                         giveup = true;
 796                         throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
 797                 }
 798         }
 799
 800         virtual ~ModuleSQL()
 801         {
 802                 DELETE(Conf);
 803         }
 804
 805         virtual void OnRehash(const std::string &parameter)
 806         {
 807                 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
 808         }
 809
 810         virtual Version GetVersion()
 811         {
 812                 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
 813         }
 814
 815 };
 816
 817 void* DispatcherThread(void* arg)
 818 {
 819         ModuleSQL* thismodule = (ModuleSQL*)arg;
 820         LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
 821
 822         /* Connect back to the Notifier */
 823
 824         if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
 825         {
 826                 /* crap, we're out of sockets... */
 827                 return NULL;
 828         }
 829
 830         insp_sockaddr addr;
 831
 832 #ifdef IPV6
 833         insp_aton("::1", &addr.sin6_addr);
 834         addr.sin6_family = AF_FAMILY;
 835         addr.sin6_port = htons(MessagePipe->GetPort());
 836 #else
 837         insp_inaddr ia;
 838         insp_aton("127.0.0.1", &ia);
 839         addr.sin_family = AF_FAMILY;
 840         addr.sin_addr = ia;
 841         addr.sin_port = htons(MessagePipe->GetPort());
 842 #endif
 843
 844         if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
 845         {
 846                 /* wtf, we cant connect to it, but we just created it! */
 847                 return NULL;
 848         }
 849
 850         while (!giveup)
 851         {
 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++)
 856                 {
 857                         if (i->second->queue.totalsize())
 858                         {
 859                                 conn = i->second;
 860                                 break;
 861                         }
 862                 }
 863                 pthread_mutex_unlock(&queue_mutex);
 864                 /* XXX: Unlock */
 865
 866                 /* Theres an item! */
 867                 if (conn)
 868                 {
 869                         conn->DoLeadingQuery();
 870
 871                         /* XXX: Lock */
 872                         pthread_mutex_lock(&queue_mutex);
 873                         conn->queue.pop();
 874                         pthread_mutex_unlock(&queue_mutex);
 875                         /* XXX: Unlock */
 876                 }
 877
 878                 usleep(50);
 879         }
 880
 881         return NULL;
 882 }
 883
 884
 885 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 886
 887 class ModuleSQLFactory : public ModuleFactory
 888 {
 889  public:
 890         ModuleSQLFactory()
 891         {
 892         }
 893
 894         ~ModuleSQLFactory()
 895         {
 896         }
 897
 898         virtual Module * CreateModule(InspIRCd* Me)
 899         {
 900                 return new ModuleSQL(Me);
 901         }
 902
 903 };
 904
 905
 906 extern "C" void * init_module( void )
 907 {
 908         return new ModuleSQLFactory;
 909 }