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 "m_sqlv2.h"
  28
  29 /* VERSION 2 API: With nonblocking (threaded) requests */
  30
  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` */
  34
  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 extern InspIRCd* ServerInstance;
  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                 log(DEBUG, "QueryQueue::push(): Adding %s query to queue: %s", ((q.pri) ? "priority" : "non-priority"), q.query.q.c_str());
 106
 107                 if(q.pri)
 108                         priority.push_back(q);
 109                 else
 110                         normal.push_back(q);
 111         }
 112
 113         void pop()
 114         {
 115                 if((which == PRI) && priority.size())
 116                 {
 117                         priority.pop_front();
 118                 }
 119                 else if((which == NOR) && normal.size())
 120                 {
 121                         normal.pop_front();
 122                 }
 123
 124                 /* Reset this */
 125                 which = NON;
 126
 127                 /* Silently do nothing if there was no element to pop() */
 128         }
 129
 130         SQLrequest& front()
 131         {
 132                 switch(which)
 133                 {
 134                         case PRI:
 135                                 return priority.front();
 136                         case NOR:
 137                                 return normal.front();
 138                         default:
 139                                 if(priority.size())
 140                                 {
 141                                         which = PRI;
 142                                         return priority.front();
 143                                 }
 144
 145                                 if(normal.size())
 146                                 {
 147                                         which = NOR;
 148                                         return normal.front();
 149                                 }
 150
 151                                 /* This will probably result in a segfault,
 152                                  * but the caller should have checked totalsize()
 153                                  * first so..meh - moron :p
 154                                  */
 155
 156                                 return priority.front();
 157                 }
 158         }
 159
 160         std::pair<int, int> size()
 161         {
 162                 return std::make_pair(priority.size(), normal.size());
 163         }
 164
 165         int totalsize()
 166         {
 167                 return priority.size() + normal.size();
 168         }
 169
 170         void PurgeModule(Module* mod)
 171         {
 172                 DoPurgeModule(mod, priority);
 173                 DoPurgeModule(mod, normal);
 174         }
 175
 176 private:
 177         void DoPurgeModule(Module* mod, ReqDeque& q)
 178         {
 179                 for(ReqDeque::iterator iter = q.begin(); iter != q.end(); iter++)
 180                 {
 181                         if(iter->GetSource() == mod)
 182                         {
 183                                 if(iter->id == front().id)
 184                                 {
 185                                         /* It's the currently active query.. :x */
 186                                         iter->SetSource(NULL);
 187                                 }
 188                                 else
 189                                 {
 190                                         /* It hasn't been executed yet..just remove it */
 191                                         iter = q.erase(iter);
 192                                 }
 193                         }
 194                 }
 195         }
 196 };
 197
 198 /* A mutex to wrap around queue accesses */
 199 pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
 200
 201 pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
 202
 203 class MySQLresult : public SQLresult
 204 {
 205         int currentrow;
 206         //std::vector<std::map<std::string,std::string> > results;
 207         std::vector<std::string> colnames;
 208         std::vector<SQLfieldList> fieldlists;
 209         SQLfieldMap* fieldmap;
 210         int rows;
 211         int cols;
 212  public:
 213
 214         MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows) : SQLresult(self, to), currentrow(0), fieldmap(NULL)
 215         {
 216                 /* A number of affected rows from from mysql_affected_rows.
 217                  */
 218                 log(DEBUG,"Created new MySQLresult of non-error type");
 219                 fieldlists.clear();
 220                 rows = 0;
 221                 if (affected_rows >= 1)
 222                 {
 223                         rows = affected_rows;
 224                         fieldlists.resize(rows);
 225                 }
 226                 unsigned int field_count;
 227                 if (res)
 228                 {
 229                         MYSQL_ROW row;
 230                         int n = 0;
 231                         while ((row = mysql_fetch_row(res)))
 232                         {
 233                                 if (fieldlists.size() < (unsigned int)rows+1)
 234                                 {
 235                                         fieldlists.resize(fieldlists.size()+1);
 236                                 }
 237                                 field_count = 0;
 238                                 MYSQL_FIELD *fields = mysql_fetch_fields(res);
 239                                 if(mysql_num_fields(res) == 0)
 240                                         break;
 241                                 if (fields && mysql_num_fields(res))
 242                                 {
 243                                         colnames.clear();
 244                                         while (field_count < mysql_num_fields(res))
 245                                         {
 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);
 251                                                 field_count++;
 252                                         }
 253                                         n++;
 254                                 }
 255                                 rows++;
 256                         }
 257                         cols = mysql_num_fields(res);
 258                         mysql_free_result(res);
 259                 }
 260                 cols = field_count;
 261                 log(DEBUG, "Created new MySQL result; %d rows, %d columns", rows, cols);
 262         }
 263
 264         MySQLresult(Module* self, Module* to, SQLerror e) : SQLresult(self, to), currentrow(0)
 265         {
 266                 rows = 0;
 267                 cols = 0;
 268                 error = e;
 269                 log(DEBUG,"Created new MySQLresult of error type");
 270         }
 271
 272         ~MySQLresult()
 273         {
 274         }
 275
 276         virtual int Rows()
 277         {
 278                 return rows;
 279         }
 280
 281         virtual int Cols()
 282         {
 283                 return cols;
 284         }
 285
 286         virtual std::string ColName(int column)
 287         {
 288                 if (column < (int)colnames.size())
 289                 {
 290                         return colnames[column];
 291                 }
 292                 else
 293                 {
 294                         throw SQLbadColName();
 295                 }
 296                 return "";
 297         }
 298
 299         virtual int ColNum(const std::string &column)
 300         {
 301                 for (unsigned int i = 0; i < colnames.size(); i++)
 302                 {
 303                         if (column == colnames[i])
 304                                 return i;
 305                 }
 306                 throw SQLbadColName();
 307                 return 0;
 308         }
 309
 310         virtual SQLfield GetValue(int row, int column)
 311         {
 312                 if ((row >= 0) && (row < rows) && (column >= 0) && (column < cols))
 313                 {
 314                         return fieldlists[row][column];
 315                 }
 316
 317                 log(DEBUG,"Danger will robinson, we don't have row %d, column %d!", row, column);
 318                 throw SQLbadColName();
 319
 320                 /* XXX: We never actually get here because of the throw */
 321                 return SQLfield("",true);
 322         }
 323
 324         virtual SQLfieldList& GetRow()
 325         {
 326                 return fieldlists[currentrow];
 327         }
 328
 329         virtual SQLfieldMap& GetRowMap()
 330         {
 331                 fieldmap = new SQLfieldMap();
 332
 333                 for (int i = 0; i < cols; i++)
 334                 {
 335                         fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
 336                 }
 337                 currentrow++;
 338
 339                 return *fieldmap;
 340         }
 341
 342         virtual SQLfieldList* GetRowPtr()
 343         {
 344                 return &fieldlists[currentrow++];
 345         }
 346
 347         virtual SQLfieldMap* GetRowMapPtr()
 348         {
 349                 fieldmap = new SQLfieldMap();
 350
 351                 for (int i = 0; i < cols; i++)
 352                 {
 353                         fieldmap->insert(std::make_pair(colnames[cols],GetValue(currentrow, i)));
 354                 }
 355                 currentrow++;
 356
 357                 return fieldmap;
 358         }
 359
 360         virtual void Free(SQLfieldMap* fm)
 361         {
 362                 delete fm;
 363         }
 364
 365         virtual void Free(SQLfieldList* fl)
 366         {
 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.
 371                  */
 372         }
 373 };
 374
 375 class SQLConnection;
 376
 377 void NotifyMainThread(SQLConnection* connection_with_new_result);
 378
 379 class SQLConnection : public classbase
 380 {
 381  protected:
 382
 383         MYSQL connection;
 384         MYSQL_RES *res;
 385         MYSQL_ROW row;
 386         std::string host;
 387         std::string user;
 388         std::string pass;
 389         std::string db;
 390         std::map<std::string,std::string> thisrow;
 391         bool Enabled;
 392         std::string id;
 393
 394  public:
 395
 396         QueryQueue queue;
 397         ResultQueue rq;
 398
 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)
 402         {
 403                 this->Enabled = true;
 404                 this->host = thishost;
 405                 this->user = thisuser;
 406                 this->pass = thispass;
 407                 this->db = thisdb;
 408                 this->id = myid;
 409         }
 410
 411         // This method connects to the database using the credentials supplied to the constructor, and returns
 412         // true upon success.
 413         bool Connect()
 414         {
 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);
 419         }
 420
 421         void DoLeadingQuery()
 422         {
 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());
 426
 427                 /* Pointer to the buffer we screw around with substitution in */
 428                 char* query;
 429
 430                 /* Pointer to the current end of query, where we append new stuff */
 431                 char* queryend;
 432
 433                 /* Total length of the unescaped parameters */
 434                 unsigned long paramlen;
 435
 436                 /* Total length of query, used for binary-safety in mysql_real_query */
 437                 unsigned long querylength = 0;
 438
 439                 paramlen = 0;
 440
 441                 for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
 442                 {
 443                         paramlen += i->size();
 444                 }
 445
 446                 /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
 447                  * sizeofquery + (totalparamlength*2) + 1
 448                  *
 449                  * The +1 is for null-terminating the string for mysql_real_escape_string
 450                  */
 451
 452                 query = new char[req.query.q.length() + (paramlen*2)];
 453                 queryend = query;
 454
 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...
 457                  */
 458
 459                 for(unsigned long i = 0; i < req.query.q.length(); i++)
 460                 {
 461                         if(req.query.q[i] == '?')
 462                         {
 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.
 468                                  */
 469                                 if(req.query.p.size())
 470                                 {
 471                                         unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
 472
 473                                         queryend += len;
 474                                         req.query.p.pop_front();
 475                                 }
 476                                 else
 477                                 {
 478                                         log(DEBUG, "Found a substitution location but no parameter to substitute :|");
 479                                         break;
 480                                 }
 481                         }
 482                         else
 483                         {
 484                                 *queryend = req.query.q[i];
 485                                 queryend++;
 486                         }
 487                         querylength++;
 488                 }
 489
 490                 *queryend = 0;
 491
 492                 log(DEBUG, "Attempting to dispatch query: %s", query);
 493
 494                 pthread_mutex_lock(&queue_mutex);
 495                 req.query.q = query;
 496                 pthread_mutex_unlock(&queue_mutex);
 497
 498                 if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
 499                 {
 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!
 508                          */
 509                         pthread_mutex_lock(&results_mutex);
 510                         rq.push_back(r);
 511                         pthread_mutex_unlock(&results_mutex);
 512                 }
 513                 else
 514                 {
 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;
 522
 523                         pthread_mutex_lock(&results_mutex);
 524                         rq.push_back(r);
 525                         pthread_mutex_unlock(&results_mutex);
 526                 }
 527
 528                 /* Now signal the main thread that we've got a result to process.
 529                  * Pass them this connection id as what to examine
 530                  */
 531
 532                 NotifyMainThread(this);
 533         }
 534
 535         bool ConnectionLost()
 536         {
 537                 if (&connection) {
 538                         return (mysql_ping(&connection) != 0);
 539                 }
 540                 else return false;
 541         }
 542
 543         bool CheckConnection()
 544         {
 545                 if (ConnectionLost()) {
 546                         return Connect();
 547                 }
 548                 else return true;
 549         }
 550
 551         std::string GetError()
 552         {
 553                 return mysql_error(&connection);
 554         }
 555
 556         const std::string& GetID()
 557         {
 558                 return id;
 559         }
 560
 561         std::string GetHost()
 562         {
 563                 return host;
 564         }
 565
 566         void SetEnable(bool Enable)
 567         {
 568                 Enabled = Enable;
 569         }
 570
 571         bool IsEnabled()
 572         {
 573                 return Enabled;
 574         }
 575
 576 };
 577
 578 ConnMap Connections;
 579
 580 void ConnectDatabases(Server* Srv)
 581 {
 582         for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
 583         {
 584                 i->second->SetEnable(true);
 585                 if (i->second->Connect())
 586                 {
 587                         Srv->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
 588                 }
 589                 else
 590                 {
 591                         Srv->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
 592                         i->second->SetEnable(false);
 593                 }
 594         }
 595 }
 596
 597
 598 void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
 599 {
 600         Srv->Log(DEFAULT,"SQL: Loading database settings");
 601         Connections.clear();
 602         Srv->Log(DEBUG,"Cleared connections");
 603         for (int j =0; j < ThisConf->Enumerate("database"); j++)
 604         {
 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 != ""))
 612                 {
 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");
 617                 }
 618         }
 619         ConnectDatabases(Srv);
 620 }
 621
 622 void NotifyMainThread(SQLConnection* connection_with_new_result)
 623 {
 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
 631          * connection back.
 632          */
 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
 635         {
 636                 log(DEBUG,"Error writing to QueueFD: %s",strerror(errno));
 637         }
 638         log(DEBUG,"Sent it on its way via fd=%d",QueueFD);
 639 }
 640
 641 void* DispatcherThread(void* arg);
 642
 643 class Notifier : public InspSocket
 644 {
 645         sockaddr_in sock_us;
 646         socklen_t uslen;
 647         Server* Srv;
 648
 649  public:
 650
 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)
 653         {
 654                 uslen = sizeof(sock_us);
 655                 if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
 656                 {
 657                         throw ModuleException("Could not create random listening port on localhost");
 658                 }
 659         }
 660
 661         Notifier(int newfd, char* ip, Server* S) : InspSocket(newfd, ip), Srv(S)
 662         {
 663                 log(DEBUG,"Constructor of new socket");
 664         }
 665
 666         /* Using getsockname and ntohs, we can determine which port number we were allocated */
 667         int GetPort()
 668         {
 669                 return ntohs(sock_us.sin_port);
 670         }
 671
 672         virtual int OnIncomingConnection(int newsock, char* ip)
 673         {
 674                 log(DEBUG,"Inbound connection on fd %d!",newsock);
 675                 Notifier* n = new Notifier(newsock, ip, Srv);
 676                 Srv->AddSocket(n);
 677                 return true;
 678         }
 679
 680         virtual bool OnDataReady()
 681         {
 682                 log(DEBUG,"Inbound data!");
 683                 char* data = this->Read();
 684                 ConnMap::iterator iter;
 685
 686                 if (data && *data)
 687                 {
 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())
 691                         {
 692                                 log(DEBUG,"Found it!");
 693
 694                                 /* Lock the mutex, send back the data */
 695                                 pthread_mutex_lock(&results_mutex);
 696                                 ResultQueue::iterator n = iter->second->rq.begin();
 697                                 (*n)->Send();
 698                                 iter->second->rq.pop_front();
 699                                 pthread_mutex_unlock(&results_mutex);
 700                                 return true;
 701                         }
 702                 }
 703
 704                 return false;
 705         }
 706 };
 707
 708 class ModuleSQL : public Module
 709 {
 710  public:
 711         Server *Srv;
 712         ConfigReader *Conf;
 713         pthread_t Dispatcher;
 714         int currid;
 715
 716         void Implements(char* List)
 717         {
 718                 List[I_OnRehash] = List[I_OnRequest] = 1;
 719         }
 720
 721         unsigned long NewID()
 722         {
 723                 if (currid+1 == 0)
 724                         currid++;
 725                 return ++currid;
 726         }
 727
 728         char* OnRequest(Request* request)
 729         {
 730                 if(strcmp(SQLREQID, request->GetData()) == 0)
 731                 {
 732                         SQLrequest* req = (SQLrequest*)request;
 733
 734                         /* XXX: Lock */
 735                         pthread_mutex_lock(&queue_mutex);
 736
 737                         ConnMap::iterator iter;
 738
 739                         char* returnval = NULL;
 740
 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());
 742
 743                         if((iter = Connections.find(req->dbid)) != Connections.end())
 744                         {
 745                                 iter->second->queue.push(*req);
 746                                 req->id = NewID();
 747                                 returnval = SQLSUCCESS;
 748                         }
 749                         else
 750                         {
 751                                 req->error.Id(BAD_DBID);
 752                         }
 753
 754                         pthread_mutex_unlock(&queue_mutex);
 755                         /* XXX: Unlock */
 756
 757                         return returnval;
 758                 }
 759
 760                 log(DEBUG, "Got unsupported API version string: %s", request->GetData());
 761
 762                 return NULL;
 763         }
 764
 765         ModuleSQL(Server* Me)
 766                 : Module::Module(Me)
 767         {
 768                 Srv = Me;
 769                 Conf = new ConfigReader();
 770                 currid = 0;
 771                 SQLModule = this;
 772
 773                 MessagePipe = new Notifier(Srv);
 774                 Srv->AddSocket(MessagePipe);
 775                 log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
 776
 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)
 781                 {
 782                         throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
 783                 }
 784                 Srv->PublishFeature("SQL", this);
 785                 Srv->PublishFeature("MySQL", this);
 786         }
 787
 788         virtual ~ModuleSQL()
 789         {
 790                 DELETE(Conf);
 791         }
 792
 793         virtual void OnRehash(const std::string &parameter)
 794         {
 795                 /* TODO: set rehash bool here, which makes the dispatcher thread rehash at next opportunity */
 796         }
 797
 798         virtual Version GetVersion()
 799         {
 800                 return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
 801         }
 802
 803 };
 804
 805 void* DispatcherThread(void* arg)
 806 {
 807         log(DEBUG,"Starting Dispatcher thread, mysql version %d",mysql_get_client_version());
 808         ModuleSQL* thismodule = (ModuleSQL*)arg;
 809         LoadDatabases(thismodule->Conf, thismodule->Srv);
 810
 811         /* Connect back to the Notifier */
 812
 813         if ((QueueFD = socket(AF_INET, SOCK_STREAM, 0)) == -1)
 814         {
 815                 /* crap, we're out of sockets... */
 816                 log(DEBUG,"QueueFD cant be created");
 817                 return NULL;
 818         }
 819
 820         log(DEBUG,"Initialize QueueFD to %d",QueueFD);
 821
 822         sockaddr_in addr;
 823         in_addr ia;
 824         inet_aton("127.0.0.1", &ia);
 825         addr.sin_family = AF_INET;
 826         addr.sin_addr = ia;
 827         addr.sin_port = htons(MessagePipe->GetPort());
 828
 829         if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
 830         {
 831                 /* wtf, we cant connect to it, but we just created it! */
 832                 log(DEBUG,"QueueFD cant connect!");
 833                 return NULL;
 834         }
 835
 836         log(DEBUG,"Connect QUEUE FD");
 837
 838         while (!giveup)
 839         {
 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++)
 844                 {
 845                         if (i->second->queue.totalsize())
 846                         {
 847                                 conn = i->second;
 848                                 break;
 849                         }
 850                 }
 851                 pthread_mutex_unlock(&queue_mutex);
 852                 /* XXX: Unlock */
 853
 854                 /* Theres an item! */
 855                 if (conn)
 856                 {
 857                         log(DEBUG,"Process Leading query");
 858                         conn->DoLeadingQuery();
 859
 860                         /* XXX: Lock */
 861                         pthread_mutex_lock(&queue_mutex);
 862                         conn->queue.pop();
 863                         pthread_mutex_unlock(&queue_mutex);
 864                         /* XXX: Unlock */
 865                 }
 866
 867                 usleep(50);
 868         }
 869
 870         return NULL;
 871 }
 872
 873
 874 // stuff down here is the module-factory stuff. For basic modules you can ignore this.
 875
 876 class ModuleSQLFactory : public ModuleFactory
 877 {
 878  public:
 879         ModuleSQLFactory()
 880         {
 881         }
 882
 883         ~ModuleSQLFactory()
 884         {
 885         }
 886
 887         virtual Module * CreateModule(Server* Me)
 888         {
 889                 return new ModuleSQL(Me);
 890         }
 891
 892 };
 893
 894
 895 extern "C" void * init_module( void )
 896 {
 897         return new ModuleSQLFactory;
 898 }
 899