]> git.netwichtig.de Git - user/henk/code/inspircd.git/blobdiff - src/modules/extra/m_mysql.cpp
This is better now.
[user/henk/code/inspircd.git] / src / modules / extra / m_mysql.cpp
index d1329151c20d203034fe3d9d3f1d919373a35297..ce0644e96fc3bfe9bf36ccc3d88719115aa93356 100644 (file)
@@ -23,26 +23,70 @@ using namespace std;
 #include "users.h"
 #include "channels.h"
 #include "modules.h"
-#include "helperfuncs.h"
+#include "inspircd.h"
 #include "m_sqlv2.h"
 
 /* VERSION 2 API: With nonblocking (threaded) requests */
 
 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
 /* $CompileFlags: `mysql_config --include` */
-/* $LinkerFlags: `mysql_config --libs_r` `perl ../mysql_rpath.pl` */
+/* $LinkerFlags: `mysql_config --libs_r` `perl extra/mysql_rpath.pl` */
+/* $ModDep: m_sqlv2.h */
+
+/* THE NONBLOCKING MYSQL API!
+ * 
+ * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
+ * that instead, you should thread your program. This is what i've done here to allow for
+ * asyncronous SQL requests via mysql. The way this works is as follows:
+ *
+ * The module spawns a thread via pthreads, and performs its mysql queries in this thread,
+ * using a queue with priorities. There is a mutex on either end which prevents two threads
+ * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
+ * worker thread wakes up, and checks if there is a request at the head of its queue.
+ * If there is, it processes this request, blocking the worker thread but leaving the ircd
+ * thread to go about its business as usual. During this period, the ircd thread is able
+ * to insert futher pending requests into the queue.
+ *
+ * Once the processing of a request is complete, it is removed from the incoming queue to
+ * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
+ * ircd thread (via a loopback socket) of the fact a result is available, by sending the
+ * connection ID through the connection.
+ *
+ * The ircd thread then mutexes the queue once more, reads the outbound response off the head
+ * of the queue, and sends it on its way to the original calling module.
+ *
+ * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
+ * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
+ * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
+ * however, if we were to call a module's OnRequest even from within a thread which was not the
+ * one the module was originally instantiated upon, there is a chance of all hell breaking loose
+ * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
+ * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
+ * gauranteed threadsafe!)
+ *
+ * For a diagram of this system please see http://www.inspircd.org/wiki/Mysql2
+ */
 
 
 class SQLConnection;
+class Notifier;
+
 
-extern InspIRCd* ServerInstance;
 typedef std::map<std::string, SQLConnection*> ConnMap;
+bool giveup = false;
+static Module* SQLModule = NULL;
+static Notifier* MessagePipe = NULL;
+int QueueFD = -1;
 
 
 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
 #define mysql_field_count mysql_num_fields
 #endif
 
+typedef std::deque<SQLresult*> ResultQueue;
+
+/** Represents a mysql query queue
+ */
 class QueryQueue : public classbase
 {
 private:
@@ -60,8 +104,6 @@ public:
 
        void push(const SQLrequest &q)
        {
-               log(DEBUG, "QueryQueue::push(): Adding %s query to queue: %s", ((q.pri) ? "priority" : "non-priority"), q.query.q.c_str());
-
                if(q.pri)
                        priority.push_back(q);
                else
@@ -153,8 +195,200 @@ private:
        }
 };
 
+/* A mutex to wrap around queue accesses */
+pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+pthread_mutex_t results_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+/** Represents a mysql result set
+ */
+class MySQLresult : public SQLresult
+{
+       int currentrow;
+       //std::vector<std::map<std::string,std::string> > results;
+       std::vector<std::string> colnames;
+       std::vector<SQLfieldList> fieldlists;
+       SQLfieldMap* fieldmap;
+       SQLfieldMap fieldmap2;
+       SQLfieldList emptyfieldlist;
+       int rows;
+ public:
+
+       MySQLresult(Module* self, Module* to, MYSQL_RES* res, int affected_rows, unsigned int id) : SQLresult(self, to, id), currentrow(0), fieldmap(NULL)
+       {
+               /* A number of affected rows from from mysql_affected_rows.
+                */
+               fieldlists.clear();
+               rows = 0;
+               if (affected_rows >= 1)
+               {
+                       rows = affected_rows;
+                       fieldlists.resize(rows);
+               }
+               unsigned int field_count = 0;
+               if (res)
+               {
+                       MYSQL_ROW row;
+                       int n = 0;
+                       while ((row = mysql_fetch_row(res)))
+                       {
+                               if (fieldlists.size() < (unsigned int)rows+1)
+                               {
+                                       fieldlists.resize(fieldlists.size()+1);
+                               }
+                               field_count = 0;
+                               MYSQL_FIELD *fields = mysql_fetch_fields(res);
+                               if(mysql_num_fields(res) == 0)
+                                       break;
+                               if (fields && mysql_num_fields(res))
+                               {
+                                       colnames.clear();
+                                       while (field_count < mysql_num_fields(res))
+                                       {
+                                               std::string a = (fields[field_count].name ? fields[field_count].name : "");
+                                               std::string b = (row[field_count] ? row[field_count] : "");
+                                               SQLfield sqlf(b, !row[field_count]);
+                                               colnames.push_back(a);
+                                               fieldlists[n].push_back(sqlf); 
+                                               field_count++;
+                                       }
+                                       n++;
+                               }
+                               rows++;
+                       }
+                       mysql_free_result(res);
+               }
+       }
+
+       MySQLresult(Module* self, Module* to, SQLerror e, unsigned int id) : SQLresult(self, to, id), currentrow(0)
+       {
+               rows = 0;
+               error = e;
+       }
+
+       ~MySQLresult()
+       {
+       }
+
+       virtual int Rows()
+       {
+               return rows;
+       }
+
+       virtual int Cols()
+       {
+               return colnames.size();
+       }
+
+       virtual std::string ColName(int column)
+       {
+               if (column < (int)colnames.size())
+               {
+                       return colnames[column];
+               }
+               else
+               {
+                       throw SQLbadColName();
+               }
+               return "";
+       }
+
+       virtual int ColNum(const std::string &column)
+       {
+               for (unsigned int i = 0; i < colnames.size(); i++)
+               {
+                       if (column == colnames[i])
+                               return i;
+               }
+               throw SQLbadColName();
+               return 0;
+       }
+
+       virtual SQLfield GetValue(int row, int column)
+       {
+               if ((row >= 0) && (row < rows) && (column >= 0) && (column < Cols()))
+               {
+                       return fieldlists[row][column];
+               }
+
+               throw SQLbadColName();
+
+               /* XXX: We never actually get here because of the throw */
+               return SQLfield("",true);
+       }
+
+       virtual SQLfieldList& GetRow()
+       {
+               if (currentrow < rows)
+                       return fieldlists[currentrow];
+               else
+                       return emptyfieldlist;
+       }
+
+       virtual SQLfieldMap& GetRowMap()
+       {
+               fieldmap2.clear();
+
+               if (currentrow < rows)
+               {
+                       for (int i = 0; i < Cols(); i++)
+                       {
+                               fieldmap2.insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
+                       }
+                       currentrow++;
+               }
+
+               return fieldmap2;
+       }
+
+       virtual SQLfieldList* GetRowPtr()
+       {
+               SQLfieldList* fieldlist = new SQLfieldList();
+
+               if (currentrow < rows)
+               {
+                       for (int i = 0; i < Rows(); i++)
+                       {
+                               fieldlist->push_back(fieldlists[currentrow][i]);
+                       }
+                       currentrow++;
+               }
+               return fieldlist;
+       }
+
+       virtual SQLfieldMap* GetRowMapPtr()
+       {
+               fieldmap = new SQLfieldMap();
+               
+               if (currentrow < rows)
+               {
+                       for (int i = 0; i < Cols(); i++)
+                       {
+                               fieldmap->insert(std::make_pair(colnames[i],GetValue(currentrow, i)));
+                       }
+                       currentrow++;
+               }
+
+               return fieldmap;
+       }
+
+       virtual void Free(SQLfieldMap* fm)
+       {
+               delete fm;
+       }
+
+       virtual void Free(SQLfieldList* fl)
+       {
+               delete fl;
+       }
+};
+
+class SQLConnection;
 
+void NotifyMainThread(SQLConnection* connection_with_new_result);
 
+/** Represents a connection to a mysql database
+ */
 class SQLConnection : public classbase
 {
  protected:
@@ -168,20 +402,16 @@ class SQLConnection : public classbase
        std::string db;
        std::map<std::string,std::string> thisrow;
        bool Enabled;
-       long id;
+       std::string id;
 
  public:
 
-       // This constructor creates an SQLConnection object with the given credentials, and creates the underlying
-       // MYSQL struct, but does not connect yet.
-       SQLConnection(std::string thishost, std::string thisuser, std::string thispass, std::string thisdb, long myid)
+       QueryQueue queue;
+       ResultQueue rq;
+
+       // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
+       SQLConnection(const std::string &thishost, const std::string &thisuser, const std::string &thispass, const std::string &thisdb, const std::string &myid) : host(thishost), user(thisuser), pass(thispass), db(thisdb), Enabled(true), id(myid)
        {
-               this->Enabled = true;
-               this->host = thishost;
-               this->user = thisuser;
-               this->pass = thispass;
-               this->db = thisdb;
-               this->id = myid;
        }
 
        // This method connects to the database using the credentials supplied to the constructor, and returns
@@ -194,78 +424,116 @@ class SQLConnection : public classbase
                return mysql_real_connect(&connection, host.c_str(), user.c_str(), pass.c_str(), db.c_str(), 0, NULL, 0);
        }
 
-       // This method issues a query that expects multiple rows of results. Use GetRow() and QueryDone() to retrieve
-       // multiple rows.
-       bool QueryResult(std::string query)
+       void DoLeadingQuery()
        {
-               if (!CheckConnection()) return false;
-               
-               int r = mysql_query(&connection, query.c_str());
-               if (!r)
-               {
-                       res = mysql_use_result(&connection);
-               }
-               return (!r);
-       }
+               if (!CheckConnection())
+                       return;
 
-       // This method issues a query that just expects a number of 'effected' rows (e.g. UPDATE or DELETE FROM).
-       // the number of effected rows is returned in the return value.
-       long QueryCount(std::string query)
-       {
-               /* If the connection is down, we return a negative value - New to 1.1 */
-               if (!CheckConnection()) return -1;
+               /* Parse the command string and dispatch it to mysql */
+               SQLrequest& req = queue.front();
+
+               /* Pointer to the buffer we screw around with substitution in */
+               char* query;
+
+               /* Pointer to the current end of query, where we append new stuff */
+               char* queryend;
+
+               /* Total length of the unescaped parameters */
+               unsigned long paramlen;
 
-               int r = mysql_query(&connection, query.c_str());
-               if (!r)
+               /* Total length of query, used for binary-safety in mysql_real_query */
+               unsigned long querylength = 0;
+
+               paramlen = 0;
+
+               for(ParamL::iterator i = req.query.p.begin(); i != req.query.p.end(); i++)
                {
-                       res = mysql_store_result(&connection);
-                       unsigned long rows = mysql_affected_rows(&connection);
-                       mysql_free_result(res);
-                       return rows;
+                       paramlen += i->size();
                }
-               return 0;
-       }
 
-       // This method fetches a row, if available from the database. You must issue a query
-       // using QueryResult() first! The row's values are returned as a map of std::string
-       // where each item is keyed by the column name.
-       std::map<std::string,std::string> GetRow()
-       {
-               thisrow.clear();
-               if (res)
+               /* To avoid a lot of allocations, allocate enough memory for the biggest the escaped query could possibly be.
+                * sizeofquery + (totalparamlength*2) + 1
+                *
+                * The +1 is for null-terminating the string for mysql_real_escape_string
+                */
+
+               query = new char[req.query.q.length() + (paramlen*2)];
+               queryend = query;
+
+               /* Okay, now we have a buffer large enough we need to start copying the query into it and escaping and substituting
+                * the parameters into it...
+                */
+
+               for(unsigned long i = 0; i < req.query.q.length(); i++)
                {
-                       row = mysql_fetch_row(res);
-                       if (row)
+                       if(req.query.q[i] == '?')
                        {
-                               unsigned int field_count = 0;
-                               MYSQL_FIELD *fields = mysql_fetch_fields(res);
-                               if(mysql_field_count(&connection) == 0)
-                                       return thisrow;
-                               if (fields && mysql_field_count(&connection))
+                               /* We found a place to substitute..what fun.
+                                * use mysql calls to escape and write the
+                                * escaped string onto the end of our query buffer,
+                                * then we "just" need to make sure queryend is
+                                * pointing at the right place.
+                                */
+                               if(req.query.p.size())
                                {
-                                       while (field_count < mysql_field_count(&connection))
-                                       {
-                                               std::string a = (fields[field_count].name ? fields[field_count].name : "");
-                                               std::string b = (row[field_count] ? row[field_count] : "");
-                                               thisrow[a] = b;
-                                               field_count++;
-                                       }
-                                       return thisrow;
+                                       unsigned long len = mysql_real_escape_string(&connection, queryend, req.query.p.front().c_str(), req.query.p.front().length());
+
+                                       queryend += len;
+                                       req.query.p.pop_front();
                                }
+                               else
+                                       break;
+                       }
+                       else
+                       {
+                               *queryend = req.query.q[i];
+                               queryend++;
                        }
+                       querylength++;
                }
-               return thisrow;
-       }
 
-       bool QueryDone()
-       {
-               if (res)
+               *queryend = 0;
+
+               pthread_mutex_lock(&queue_mutex);
+               req.query.q = query;
+               pthread_mutex_unlock(&queue_mutex);
+
+               if (!mysql_real_query(&connection, req.query.q.data(), req.query.q.length()))
                {
-                       mysql_free_result(res);
-                       res = NULL;
-                       return true;
+                       /* Successfull query */
+                       res = mysql_use_result(&connection);
+                       unsigned long rows = mysql_affected_rows(&connection);
+                       MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), res, rows, req.id);
+                       r->dbid = this->GetID();
+                       r->query = req.query.q;
+                       /* Put this new result onto the results queue.
+                        * XXX: Remember to mutex the queue!
+                        */
+                       pthread_mutex_lock(&results_mutex);
+                       rq.push_back(r);
+                       pthread_mutex_unlock(&results_mutex);
                }
-               else return false;
+               else
+               {
+                       /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
+                        * possible error numbers and error messages */
+                       SQLerror e(QREPLY_FAIL, ConvToStr(mysql_errno(&connection)) + std::string(": ") + mysql_error(&connection));
+                       MySQLresult* r = new MySQLresult(SQLModule, req.GetSource(), e, req.id);
+                       r->dbid = this->GetID();
+                       r->query = req.query.q;
+
+                       pthread_mutex_lock(&results_mutex);
+                       rq.push_back(r);
+                       pthread_mutex_unlock(&results_mutex);
+               }
+
+               /* Now signal the main thread that we've got a result to process.
+                * Pass them this connection id as what to examine
+                */
+
+               delete[] query;
+
+               NotifyMainThread(this);
        }
 
        bool ConnectionLost()
@@ -289,7 +557,7 @@ class SQLConnection : public classbase
                return mysql_error(&connection);
        }
 
-       long GetID()
+       const std::string& GetID()
        {
                return id;
        }
@@ -299,14 +567,9 @@ class SQLConnection : public classbase
                return host;
        }
 
-       void Enable()
-       {
-               Enabled = true;
-       }
-
-       void Disable()
+       void SetEnable(bool Enable)
        {
-               Enabled = false;
+               Enabled = Enable;
        }
 
        bool IsEnabled()
@@ -318,29 +581,29 @@ class SQLConnection : public classbase
 
 ConnMap Connections;
 
-void ConnectDatabases(Server* Srv)
+void ConnectDatabases(InspIRCd* ServerInstance)
 {
        for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
        {
-               i->second->Enable();
+               i->second->SetEnable(true);
                if (i->second->Connect())
                {
-                       Srv->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
+                       ServerInstance->Log(DEFAULT,"SQL: Successfully connected database "+i->second->GetHost());
                }
                else
                {
-                       Srv->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
-                       i->second->Disable();
+                       ServerInstance->Log(DEFAULT,"SQL: Failed to connect database "+i->second->GetHost()+": Error: "+i->second->GetError());
+                       i->second->SetEnable(false);
                }
        }
 }
 
 
-void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
+void LoadDatabases(ConfigReader* ThisConf, InspIRCd* ServerInstance)
 {
-       Srv->Log(DEFAULT,"SQL: Loading database settings");
+       ServerInstance->Log(DEFAULT,"SQL: Loading database settings");
        Connections.clear();
-       Srv->Log(DEBUG,"Cleared connections");
+       ServerInstance->Log(DEBUG,"Cleared connections");
        for (int j =0; j < ThisConf->Enumerate("database"); j++)
        {
                std::string db = ThisConf->ReadValue("database","name",j);
@@ -348,48 +611,193 @@ void LoadDatabases(ConfigReader* ThisConf, Server* Srv)
                std::string pass = ThisConf->ReadValue("database","password",j);
                std::string host = ThisConf->ReadValue("database","hostname",j);
                std::string id = ThisConf->ReadValue("database","id",j);
-               Srv->Log(DEBUG,"Read database settings");
+               ServerInstance->Log(DEBUG,"Read database settings");
                if ((db != "") && (host != "") && (user != "") && (id != "") && (pass != ""))
                {
-                       SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,atoi(id.c_str()));
-                       Srv->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
+                       SQLConnection* ThisSQL = new SQLConnection(host,user,pass,db,id);
+                       ServerInstance->Log(DEFAULT,"Loaded database: "+ThisSQL->GetHost());
                        Connections[id] = ThisSQL;
-                       Srv->Log(DEBUG,"Pushed back connection");
+                       ServerInstance->Log(DEBUG,"Pushed back connection");
                }
        }
-       ConnectDatabases(Srv);
+       ConnectDatabases(ServerInstance);
+}
+
+void NotifyMainThread(SQLConnection* connection_with_new_result)
+{
+       /* Here we write() to the socket the main thread has open
+        * and we connect()ed back to before our thread became active.
+        * The main thread is using a nonblocking socket tied into
+        * the socket engine, so they wont block and they'll receive
+        * nearly instant notification. Because we're in a seperate
+        * thread, we can just use standard connect(), and we can
+        * block if we like. We just send the connection id of the
+        * connection back.
+        */
+       send(QueueFD, connection_with_new_result->GetID().c_str(), connection_with_new_result->GetID().length()+1, 0);
 }
 
 void* DispatcherThread(void* arg);
 
+/** Used by m_mysql to notify one thread when the other has a result
+ */
+class Notifier : public InspSocket
+{
+       insp_sockaddr sock_us;
+       socklen_t uslen;
+       
+
+ public:
+
+       /* Create a socket on a random port. Let the tcp stack allocate us an available port */
+#ifdef IPV6
+       Notifier(InspIRCd* SI) : InspSocket(SI, "::1", 0, true, 3000)
+#else
+       Notifier(InspIRCd* SI) : InspSocket(SI, "127.0.0.1", 0, true, 3000)
+#endif
+       {
+               uslen = sizeof(sock_us);
+               if (getsockname(this->fd,(sockaddr*)&sock_us,&uslen))
+               {
+                       throw ModuleException("Could not create random listening port on localhost");
+               }
+       }
+
+       Notifier(InspIRCd* SI, int newfd, char* ip) : InspSocket(SI, newfd, ip)
+       {
+               Instance->Log(DEBUG,"Constructor of new socket");
+       }
+
+       /* Using getsockname and ntohs, we can determine which port number we were allocated */
+       int GetPort()
+       {
+#ifdef IPV6
+               return ntohs(sock_us.sin6_port);
+#else
+               return ntohs(sock_us.sin_port);
+#endif
+       }
+
+       virtual int OnIncomingConnection(int newsock, char* ip)
+       {
+               Instance->Log(DEBUG,"Inbound connection on fd %d!",newsock);
+               Notifier* n = new Notifier(this->Instance, newsock, ip);
+               n = n; /* Stop bitching at me, GCC */
+               return true;
+       }
+
+       virtual bool OnDataReady()
+       {
+               Instance->Log(DEBUG,"Inbound data!");
+               char* data = this->Read();
+               ConnMap::iterator iter;
+
+               if (data && *data)
+               {
+                       Instance->Log(DEBUG,"Looking for connection %s",data);
+                       /* We expect to be sent a null terminated string */
+                       if((iter = Connections.find(data)) != Connections.end())
+                       {
+                               Instance->Log(DEBUG,"Found it!");
+
+                               /* Lock the mutex, send back the data */
+                               pthread_mutex_lock(&results_mutex);
+                               ResultQueue::iterator n = iter->second->rq.begin();
+                               (*n)->Send();
+                               iter->second->rq.pop_front();
+                               pthread_mutex_unlock(&results_mutex);
+                               return true;
+                       }
+               }
+
+               return false;
+       }
+};
+
+/** MySQL module
+ */
 class ModuleSQL : public Module
 {
  public:
-       Server *Srv;
+       
        ConfigReader *Conf;
+       InspIRCd* PublicServerInstance;
        pthread_t Dispatcher;
+       int currid;
 
        void Implements(char* List)
        {
                List[I_OnRehash] = List[I_OnRequest] = 1;
        }
 
+       unsigned long NewID()
+       {
+               if (currid+1 == 0)
+                       currid++;
+               return ++currid;
+       }
+
        char* OnRequest(Request* request)
        {
+               if(strcmp(SQLREQID, request->GetId()) == 0)
+               {
+                       SQLrequest* req = (SQLrequest*)request;
+
+                       /* XXX: Lock */
+                       pthread_mutex_lock(&queue_mutex);
+
+                       ConnMap::iterator iter;
+
+                       char* returnval = NULL;
+
+                       ServerInstance->Log(DEBUG, "Got query: '%s' with %d replacement parameters on id '%s'", req->query.q.c_str(), req->query.p.size(), req->dbid.c_str());
+
+                       if((iter = Connections.find(req->dbid)) != Connections.end())
+                       {
+                               req->id = NewID();
+                               iter->second->queue.push(*req);
+                               returnval = SQLSUCCESS;
+                       }
+                       else
+                       {
+                               req->error.Id(BAD_DBID);
+                       }
+
+                       pthread_mutex_unlock(&queue_mutex);
+                       /* XXX: Unlock */
+
+                       return returnval;
+               }
+
+               ServerInstance->Log(DEBUG, "Got unsupported API version string: %s", request->GetId());
+
                return NULL;
        }
 
-       ModuleSQL(Server* Me)
+       ModuleSQL(InspIRCd* Me)
                : Module::Module(Me)
        {
-               Srv = Me;
-               Conf = new ConfigReader();
+               
+               Conf = new ConfigReader(ServerInstance);
+               PublicServerInstance = ServerInstance;
+               currid = 0;
+               SQLModule = this;
+
+               MessagePipe = new Notifier(ServerInstance);
+               ServerInstance->Log(DEBUG,"Bound notifier to 127.0.0.1:%d",MessagePipe->GetPort());
+               
                pthread_attr_t attribs;
                pthread_attr_init(&attribs);
                pthread_attr_setdetachstate(&attribs, PTHREAD_CREATE_DETACHED);
                if (pthread_create(&this->Dispatcher, &attribs, DispatcherThread, (void *)this) != 0)
                {
-                       log(DEBUG,"m_mysql: Failed to create dispatcher thread: %s", strerror(errno));
+                       throw ModuleException("m_mysql: Failed to create dispatcher thread: " + std::string(strerror(errno)));
+               }
+               if (!ServerInstance->PublishFeature("SQL", this))
+               {
+                       /* Tell worker thread to exit NOW */
+                       giveup = true;
+                       throw ModuleException("m_mysql: Unable to publish feature 'SQL'");
                }
        }
        
@@ -405,7 +813,7 @@ class ModuleSQL : public Module
        
        virtual Version GetVersion()
        {
-               return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER);
+               return Version(1,1,0,0,VF_VENDOR|VF_SERVICEPROVIDER,API_VERSION);
        }
        
 };
@@ -413,7 +821,66 @@ class ModuleSQL : public Module
 void* DispatcherThread(void* arg)
 {
        ModuleSQL* thismodule = (ModuleSQL*)arg;
-       LoadDatabases(thismodule->Conf, thismodule->Srv);
+       LoadDatabases(thismodule->Conf, thismodule->PublicServerInstance);
+
+       /* Connect back to the Notifier */
+
+       if ((QueueFD = socket(AF_FAMILY, SOCK_STREAM, 0)) == -1)
+       {
+               /* crap, we're out of sockets... */
+               return NULL;
+       }
+
+       insp_sockaddr addr;
+
+#ifdef IPV6
+       insp_aton("::1", &addr.sin6_addr);
+       addr.sin6_family = AF_FAMILY;
+       addr.sin6_port = htons(MessagePipe->GetPort());
+#else
+       insp_inaddr ia;
+       insp_aton("127.0.0.1", &ia);
+       addr.sin_family = AF_FAMILY;
+       addr.sin_addr = ia;
+       addr.sin_port = htons(MessagePipe->GetPort());
+#endif
+
+       if (connect(QueueFD, (sockaddr*)&addr,sizeof(addr)) == -1)
+       {
+               /* wtf, we cant connect to it, but we just created it! */
+               return NULL;
+       }
+
+       while (!giveup)
+       {
+               SQLConnection* conn = NULL;
+               /* XXX: Lock here for safety */
+               pthread_mutex_lock(&queue_mutex);
+               for (ConnMap::iterator i = Connections.begin(); i != Connections.end(); i++)
+               {
+                       if (i->second->queue.totalsize())
+                       {
+                               conn = i->second;
+                               break;
+                       }
+               }
+               pthread_mutex_unlock(&queue_mutex);
+               /* XXX: Unlock */
+
+               /* Theres an item! */
+               if (conn)
+               {
+                       conn->DoLeadingQuery();
+
+                       /* XXX: Lock */
+                       pthread_mutex_lock(&queue_mutex);
+                       conn->queue.pop();
+                       pthread_mutex_unlock(&queue_mutex);
+                       /* XXX: Unlock */
+               }
+
+               usleep(50);
+       }
 
        return NULL;
 }
@@ -432,7 +899,7 @@ class ModuleSQLFactory : public ModuleFactory
        {
        }
        
-       virtual Module * CreateModule(Server* Me)
+       virtual Module * CreateModule(InspIRCd* Me)
        {
                return new ModuleSQL(Me);
        }
@@ -444,4 +911,3 @@ extern "C" void * init_module( void )
 {
        return new ModuleSQLFactory;
 }
-