2 * InspIRCd -- Internet Relay Chat Daemon
4 * Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
5 * Copyright (C) 2006-2007, 2009 Dennis Friis <peavey@inspircd.org>
6 * Copyright (C) 2006-2009 Craig Edwards <craigedwards@brainbox.cc>
7 * Copyright (C) 2008 Robin Burchell <robin+git@viroteck.net>
9 * This file is part of InspIRCd. InspIRCd is free software: you can
10 * redistribute it and/or modify it under the terms of the GNU General Public
11 * License as published by the Free Software Foundation, version 2.
13 * This program is distributed in the hope that it will be useful, but WITHOUT
14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
15 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
18 * You should have received a copy of the GNU General Public License
19 * along with this program. If not, see <http://www.gnu.org/licenses/>.
23 /* Stop mysql wanting to use long long */
24 #define NO_CLIENT_LONG_LONG
31 # pragma comment(lib, "libmysql.lib")
34 /* VERSION 3 API: With nonblocking (threaded) requests */
36 /* $ModDesc: SQL Service Provider module for all other m_sql* modules */
37 /* $CompileFlags: exec("mysql_config --include") */
38 /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */
40 /* THE NONBLOCKING MYSQL API!
42 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
43 * that instead, you should thread your program. This is what i've done here to allow for
44 * asyncronous SQL requests via mysql. The way this works is as follows:
46 * The module spawns a thread via class Thread, and performs its mysql queries in this thread,
47 * using a queue with priorities. There is a mutex on either end which prevents two threads
48 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
49 * worker thread wakes up, and checks if there is a request at the head of its queue.
50 * If there is, it processes this request, blocking the worker thread but leaving the ircd
51 * thread to go about its business as usual. During this period, the ircd thread is able
52 * to insert futher pending requests into the queue.
54 * Once the processing of a request is complete, it is removed from the incoming queue to
55 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
56 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
57 * connection ID through the connection.
59 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
60 * of the queue, and sends it on its way to the original calling module.
62 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
63 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
64 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
65 * however, if we were to call a module's OnRequest even from within a thread which was not the
66 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
67 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
68 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
69 * gauranteed threadsafe!)
74 class DispatcherThread;
81 QQueueItem(SQLQuery* Q, const std::string& S, SQLConnection* C) : q(Q), query(S), c(C) {}
88 RQueueItem(SQLQuery* Q, MySQLresult* R) : q(Q), r(R) {}
91 typedef std::map<std::string, SQLConnection*> ConnMap;
92 typedef std::deque<QQueueItem> QueryQueue;
93 typedef std::deque<RQueueItem> ResultQueue;
97 class ModuleSQL : public Module
100 DispatcherThread* Dispatcher;
101 QueryQueue qq; // MUST HOLD MUTEX
102 ResultQueue rq; // MUST HOLD MUTEX
103 ConnMap connections; // main thread only
108 void OnRehash(User* user);
109 void OnUnloadModule(Module* mod);
110 Version GetVersion();
113 class DispatcherThread : public SocketThread
116 ModuleSQL* const Parent;
118 DispatcherThread(ModuleSQL* CreatorModule) : Parent(CreatorModule) { }
119 ~DispatcherThread() { }
121 virtual void OnNotify();
124 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
125 #define mysql_field_count mysql_num_fields
128 /** Represents a mysql result set
130 class MySQLresult : public SQLResult
136 std::vector<std::string> colnames;
137 std::vector<SQLEntries> fieldlists;
139 MySQLresult(MYSQL_RES* res, int affected_rows) : err(SQL_NO_ERROR), currentrow(0), rows(0)
141 if (affected_rows >= 1)
143 rows = affected_rows;
144 fieldlists.resize(rows);
146 unsigned int field_count = 0;
151 while ((row = mysql_fetch_row(res)))
153 if (fieldlists.size() < (unsigned int)rows+1)
155 fieldlists.resize(fieldlists.size()+1);
158 MYSQL_FIELD *fields = mysql_fetch_fields(res);
159 if(mysql_num_fields(res) == 0)
161 if (fields && mysql_num_fields(res))
164 while (field_count < mysql_num_fields(res))
166 std::string a = (fields[field_count].name ? fields[field_count].name : "");
167 if (row[field_count])
168 fieldlists[n].push_back(SQLEntry(row[field_count]));
170 fieldlists[n].push_back(SQLEntry());
171 colnames.push_back(a);
178 mysql_free_result(res);
182 MySQLresult(SQLerror& e) : err(e)
196 virtual void GetCols(std::vector<std::string>& result)
198 result.assign(colnames.begin(), colnames.end());
201 virtual SQLEntry GetValue(int row, int column)
203 if ((row >= 0) && (row < rows) && (column >= 0) && (column < (int)fieldlists[row].size()))
205 return fieldlists[row][column];
210 virtual bool GetRow(SQLEntries& result)
212 if (currentrow < rows)
214 result.assign(fieldlists[currentrow].begin(), fieldlists[currentrow].end());
226 /** Represents a connection to a mysql database
228 class SQLConnection : public SQLProvider
231 reference<ConfigTag> config;
235 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
236 SQLConnection(Module* p, ConfigTag* tag) : SQLProvider(p, "SQL/" + tag->getString("id")),
237 config(tag), connection(NULL)
246 // This method connects to the database using the credentials supplied to the constructor, and returns
247 // true upon success.
250 unsigned int timeout = 1;
251 connection = mysql_init(connection);
252 mysql_options(connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
253 std::string host = config->getString("host");
254 std::string user = config->getString("user");
255 std::string pass = config->getString("pass");
256 std::string dbname = config->getString("name");
257 int port = config->getInt("port");
258 bool rv = mysql_real_connect(connection, host.c_str(), user.c_str(), pass.c_str(), dbname.c_str(), port, NULL, 0);
261 std::string initquery;
262 if (config->readString("initialquery", initquery))
264 mysql_query(connection,initquery.c_str());
271 return (ModuleSQL*)(Module*)creator;
274 MySQLresult* DoBlockingQuery(const std::string& query)
277 /* Parse the command string and dispatch it to mysql */
278 if (CheckConnection() && !mysql_real_query(connection, query.data(), query.length()))
280 /* Successfull query */
281 MYSQL_RES* res = mysql_use_result(connection);
282 unsigned long rows = mysql_affected_rows(connection);
283 return new MySQLresult(res, rows);
287 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
288 * possible error numbers and error messages */
289 SQLerror e(SQL_QREPLY_FAIL, ConvToStr(mysql_errno(connection)) + ": " + mysql_error(connection));
290 return new MySQLresult(e);
294 bool CheckConnection()
296 if (!connection || mysql_ping(connection) != 0)
301 std::string GetError()
303 return mysql_error(connection);
308 mysql_close(connection);
311 void submit(SQLQuery* q, const std::string& qs)
313 Parent()->Dispatcher->LockQueue();
314 Parent()->qq.push_back(QQueueItem(q, qs, this));
315 Parent()->Dispatcher->UnlockQueueWakeup();
318 void submit(SQLQuery* call, const std::string& q, const ParamL& p)
321 unsigned int param = 0;
322 for(std::string::size_type i = 0; i < q.length(); i++)
328 if (param < p.size())
330 std::string parm = p[param++];
331 // In the worst case, each character may need to be encoded as using two bytes,
332 // and one byte is the terminating null
333 std::vector<char> buffer(parm.length() * 2 + 1);
335 // The return value of mysql_escape_string() is the length of the encoded string,
336 // not including the terminating null
337 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
338 // mysql_real_escape_string(connection, queryend, paramscopy[paramnum].c_str(), paramscopy[paramnum].length());
339 res.append(&buffer[0], escapedsize);
346 void submit(SQLQuery* call, const std::string& q, const ParamM& p)
349 for(std::string::size_type i = 0; i < q.length(); i++)
357 while (i < q.length() && isalnum(q[i]))
358 field.push_back(q[i++]);
361 ParamM::const_iterator it = p.find(field);
364 std::string parm = it->second;
366 std::vector<char> buffer(parm.length() * 2 + 1);
367 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
368 res.append(&buffer[0], escapedsize);
376 ModuleSQL::ModuleSQL()
381 void ModuleSQL::init()
383 Dispatcher = new DispatcherThread(this);
384 ServerInstance->Threads->Start(Dispatcher);
386 Implementation eventlist[] = { I_OnRehash, I_OnUnloadModule };
387 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
392 ModuleSQL::~ModuleSQL()
397 Dispatcher->OnNotify();
400 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
406 void ModuleSQL::OnRehash(User* user)
409 ConfigTagList tags = ServerInstance->Config->ConfTags("database");
410 for(ConfigIter i = tags.first; i != tags.second; i++)
412 if (i->second->getString("module", "mysql") != "mysql")
414 std::string id = i->second->getString("id");
415 ConnMap::iterator curr = connections.find(id);
416 if (curr == connections.end())
418 SQLConnection* conn = new SQLConnection(this, i->second);
419 conns.insert(std::make_pair(id, conn));
420 ServerInstance->Modules->AddService(*conn);
425 connections.erase(curr);
429 // now clean up the deleted databases
430 Dispatcher->LockQueue();
431 SQLerror err(SQL_BAD_DBID);
432 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
434 ServerInstance->Modules->DelService(*i->second);
435 // it might be running a query on this database. Wait for that to complete
436 i->second->lock.Lock();
437 i->second->lock.Unlock();
438 // now remove all active queries to this DB
439 for (size_t j = qq.size(); j > 0; j--)
442 if (qq[k].c == i->second)
444 qq[k].q->OnError(err);
446 qq.erase(qq.begin() + k);
449 // finally, nuke the connection
452 Dispatcher->UnlockQueue();
453 connections.swap(conns);
456 void ModuleSQL::OnUnloadModule(Module* mod)
458 SQLerror err(SQL_BAD_DBID);
459 Dispatcher->LockQueue();
460 unsigned int i = qq.size();
464 if (qq[i].q->creator == mod)
468 // need to wait until the query is done
469 // (the result will be discarded)
470 qq[i].c->lock.Lock();
471 qq[i].c->lock.Unlock();
473 qq[i].q->OnError(err);
475 qq.erase(qq.begin() + i);
478 Dispatcher->UnlockQueue();
479 // clean up any result queue entries
480 Dispatcher->OnNotify();
483 Version ModuleSQL::GetVersion()
485 return Version("MySQL support", VF_VENDOR);
488 void DispatcherThread::Run()
491 while (!this->GetExitFlag())
493 if (!Parent->qq.empty())
495 QQueueItem i = Parent->qq.front();
498 MySQLresult* res = i.c->DoBlockingQuery(i.query);
502 * At this point, the main thread could be working on:
503 * Rehash - delete i.c out from under us. We don't care about that.
504 * UnloadModule - delete i.q and the qq item. Need to avoid reporting results.
508 if (!Parent->qq.empty() && Parent->qq.front().q == i.q)
510 Parent->qq.pop_front();
511 Parent->rq.push_back(RQueueItem(i.q, res));
516 // UnloadModule ate the query
522 /* We know the queue is empty, we can safely hang this thread until
525 this->WaitForQueue();
531 void DispatcherThread::OnNotify()
533 // this could unlock during the dispatch, but OnResult isn't expected to take that long
535 for(ResultQueue::iterator i = Parent->rq.begin(); i != Parent->rq.end(); i++)
537 MySQLresult* res = i->r;
538 if (res->err.id == SQL_NO_ERROR)
539 i->q->OnResult(*res);
541 i->q->OnError(res->err);
549 MODULE_INIT(ModuleSQL)