1 /* +------------------------------------+
2 * | Inspire Internet Relay Chat Daemon |
3 * +------------------------------------+
5 * InspIRCd: (C) 2002-2010 InspIRCd Development Team
6 * See: http://wiki.inspircd.org/Credits
8 * This program is free but copyrighted software; see
9 * the file COPYING for details.
11 * ---------------------------------------------------
14 /* Stop mysql wanting to use long long */
15 #define NO_CLIENT_LONG_LONG
22 #pragma comment(lib, "mysqlclient.lib")
25 /* VERSION 3 API: With nonblocking (threaded) requests */
27 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
28 /* $CompileFlags: exec("mysql_config --include") */
29 /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */
31 /* THE NONBLOCKING MYSQL API!
33 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
34 * that instead, you should thread your program. This is what i've done here to allow for
35 * asyncronous SQL requests via mysql. The way this works is as follows:
37 * The module spawns a thread via class Thread, and performs its mysql queries in this thread,
38 * using a queue with priorities. There is a mutex on either end which prevents two threads
39 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
40 * worker thread wakes up, and checks if there is a request at the head of its queue.
41 * If there is, it processes this request, blocking the worker thread but leaving the ircd
42 * thread to go about its business as usual. During this period, the ircd thread is able
43 * to insert futher pending requests into the queue.
45 * Once the processing of a request is complete, it is removed from the incoming queue to
46 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
47 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
48 * connection ID through the connection.
50 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
51 * of the queue, and sends it on its way to the original calling module.
53 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
54 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
55 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
56 * however, if we were to call a module's OnRequest even from within a thread which was not the
57 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
58 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
59 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
60 * gauranteed threadsafe!)
62 * For a diagram of this system please see http://wiki.inspircd.org/Mysql2
67 class DispatcherThread;
74 QQueueItem(SQLQuery* Q, const std::string& S, SQLConnection* C) : q(Q), query(S), c(C) {}
81 RQueueItem(SQLQuery* Q, MySQLresult* R) : q(Q), r(R) {}
84 typedef std::map<std::string, SQLConnection*> ConnMap;
85 typedef std::deque<QQueueItem> QueryQueue;
86 typedef std::deque<RQueueItem> ResultQueue;
90 class ModuleSQL : public Module
93 DispatcherThread* Dispatcher;
94 QueryQueue qq; // MUST HOLD MUTEX
95 ResultQueue rq; // MUST HOLD MUTEX
96 ConnMap connections; // main thread only
101 void OnRehash(User* user);
102 void OnUnloadModule(Module* mod);
103 Version GetVersion();
106 class DispatcherThread : public SocketThread
109 ModuleSQL* const Parent;
111 DispatcherThread(ModuleSQL* CreatorModule) : Parent(CreatorModule) { }
112 ~DispatcherThread() { }
114 virtual void OnNotify();
117 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
118 #define mysql_field_count mysql_num_fields
121 /** Represents a mysql result set
123 class MySQLresult : public SQLResult
129 std::vector<std::string> colnames;
130 std::vector<SQLEntries> fieldlists;
132 MySQLresult(MYSQL_RES* res, int affected_rows) : err(SQL_NO_ERROR), currentrow(0), rows(0)
134 if (affected_rows >= 1)
136 rows = affected_rows;
137 fieldlists.resize(rows);
139 unsigned int field_count = 0;
144 while ((row = mysql_fetch_row(res)))
146 if (fieldlists.size() < (unsigned int)rows+1)
148 fieldlists.resize(fieldlists.size()+1);
151 MYSQL_FIELD *fields = mysql_fetch_fields(res);
152 if(mysql_num_fields(res) == 0)
154 if (fields && mysql_num_fields(res))
157 while (field_count < mysql_num_fields(res))
159 std::string a = (fields[field_count].name ? fields[field_count].name : "");
160 if (row[field_count])
161 fieldlists[n].push_back(SQLEntry(row[field_count]));
163 fieldlists[n].push_back(SQLEntry());
164 colnames.push_back(a);
171 mysql_free_result(res);
176 MySQLresult(SQLerror& e) : err(e)
190 virtual void GetCols(std::vector<std::string>& result)
192 result.assign(colnames.begin(), colnames.end());
195 virtual SQLEntry GetValue(int row, int column)
197 if ((row >= 0) && (row < rows) && (column >= 0) && (column < (int)fieldlists[row].size()))
199 return fieldlists[row][column];
204 virtual bool GetRow(SQLEntries& result)
206 if (currentrow < rows)
208 result.assign(fieldlists[currentrow].begin(), fieldlists[currentrow].end());
220 /** Represents a connection to a mysql database
222 class SQLConnection : public SQLProvider
225 reference<ConfigTag> config;
229 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
230 SQLConnection(Module* p, ConfigTag* tag) : SQLProvider(p, "SQL/" + tag->getString("id")),
231 config(tag), connection(NULL)
240 // This method connects to the database using the credentials supplied to the constructor, and returns
241 // true upon success.
244 unsigned int timeout = 1;
245 connection = mysql_init(connection);
246 mysql_options(connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
247 std::string host = config->getString("host");
248 std::string user = config->getString("user");
249 std::string pass = config->getString("pass");
250 std::string dbname = config->getString("name");
251 int port = config->getInt("port");
252 bool rv = mysql_real_connect(connection, host.c_str(), user.c_str(), pass.c_str(), dbname.c_str(), port, NULL, 0);
255 std::string initquery;
256 if (config->readString("initialquery", initquery))
258 mysql_query(connection,initquery.c_str());
265 return (ModuleSQL*)(Module*)creator;
268 MySQLresult* DoBlockingQuery(const std::string& query)
271 /* Parse the command string and dispatch it to mysql */
272 if (CheckConnection() && !mysql_real_query(connection, query.data(), query.length()))
274 /* Successfull query */
275 MYSQL_RES* res = mysql_use_result(connection);
276 unsigned long rows = mysql_affected_rows(connection);
277 return new MySQLresult(res, rows);
281 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
282 * possible error numbers and error messages */
283 SQLerror e(SQL_QREPLY_FAIL, ConvToStr(mysql_errno(connection)) + std::string(": ") + mysql_error(connection));
284 return new MySQLresult(e);
288 bool CheckConnection()
290 if (!connection || mysql_ping(connection) != 0)
295 std::string GetError()
297 return mysql_error(connection);
302 mysql_close(connection);
305 void submit(SQLQuery* q, const std::string& qs)
307 Parent()->Dispatcher->LockQueue();
308 Parent()->qq.push_back(QQueueItem(q, qs, this));
309 Parent()->Dispatcher->UnlockQueueWakeup();
312 void submit(SQLQuery* call, const std::string& q, const ParamL& p)
315 unsigned int param = 0;
316 for(std::string::size_type i = 0; i < q.length(); i++)
322 if (param < p.size())
324 std::string parm = p[param++];
326 mysql_escape_string(buffer, parm.c_str(), parm.length());
327 // mysql_real_escape_string(connection, queryend, paramscopy[paramnum].c_str(), paramscopy[paramnum].length());
335 void submit(SQLQuery* call, const std::string& q, const ParamM& p)
338 for(std::string::size_type i = 0; i < q.length(); i++)
346 while (i < q.length() && isalnum(q[i]))
347 field.push_back(q[i++]);
350 ParamM::const_iterator it = p.find(field);
353 std::string parm = it->second;
355 mysql_escape_string(buffer, parm.c_str(), parm.length());
364 ModuleSQL::ModuleSQL()
369 void ModuleSQL::init()
371 Dispatcher = new DispatcherThread(this);
372 ServerInstance->Threads->Start(Dispatcher);
374 Implementation eventlist[] = { I_OnRehash, I_OnUnloadModule };
375 ServerInstance->Modules->Attach(eventlist, this, 2);
380 ModuleSQL::~ModuleSQL()
385 Dispatcher->OnNotify();
388 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
394 void ModuleSQL::OnRehash(User* user)
397 ConfigTagList tags = ServerInstance->Config->ConfTags("database");
398 for(ConfigIter i = tags.first; i != tags.second; i++)
400 if (i->second->getString("module", "mysql") != "mysql")
402 std::string id = i->second->getString("id");
403 ConnMap::iterator curr = connections.find(id);
404 if (curr == connections.end())
406 SQLConnection* conn = new SQLConnection(this, i->second);
407 conns.insert(std::make_pair(id, conn));
408 ServerInstance->Modules->AddService(*conn);
413 connections.erase(curr);
417 // now clean up the deleted databases
418 Dispatcher->LockQueue();
419 SQLerror err(SQL_BAD_DBID);
420 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
422 ServerInstance->Modules->DelService(*i->second);
423 // it might be running a query on this database. Wait for that to complete
424 i->second->lock.Lock();
425 i->second->lock.Unlock();
426 // now remove all active queries to this DB
427 for(unsigned int j = qq.size() - 1; j >= 0; j--)
429 if (qq[j].c == i->second)
431 qq[j].q->OnError(err);
433 qq.erase(qq.begin() + j);
436 // finally, nuke the connection
439 Dispatcher->UnlockQueue();
440 connections.swap(conns);
443 void ModuleSQL::OnUnloadModule(Module* mod)
445 SQLerror err(SQL_BAD_DBID);
446 Dispatcher->LockQueue();
447 unsigned int i = qq.size();
451 if (qq[i].q->creator == mod)
455 // need to wait until the query is done
456 // (the result will be discarded)
457 qq[i].c->lock.Lock();
458 qq[i].c->lock.Unlock();
460 qq[i].q->OnError(err);
462 qq.erase(qq.begin() + i);
465 Dispatcher->UnlockQueue();
466 // clean up any result queue entries
467 Dispatcher->OnNotify();
470 Version ModuleSQL::GetVersion()
472 return Version("MySQL support", VF_VENDOR);
475 void DispatcherThread::Run()
478 while (!this->GetExitFlag())
480 if (!Parent->qq.empty())
482 QQueueItem i = Parent->qq.front();
485 MySQLresult* res = i.c->DoBlockingQuery(i.query);
489 * At this point, the main thread could be working on:
490 * Rehash - delete i.c out from under us. We don't care about that.
491 * UnloadModule - delete i.q and the qq item. Need to avoid reporting results.
495 if (Parent->qq.front().q == i.q)
497 Parent->qq.pop_front();
498 Parent->rq.push_back(RQueueItem(i.q, res));
503 // UnloadModule ate the query
509 /* We know the queue is empty, we can safely hang this thread until
512 this->WaitForQueue();
518 void DispatcherThread::OnNotify()
520 // this could unlock during the dispatch, but OnResult isn't expected to take that long
522 for(ResultQueue::iterator i = Parent->rq.begin(); i != Parent->rq.end(); i++)
524 MySQLresult* res = i->r;
525 if (res->err.id == SQL_NO_ERROR)
526 i->q->OnResult(*res);
528 i->q->OnError(res->err);
536 MODULE_INIT(ModuleSQL)