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") */
30 /* $ModDep: m_sqlv2.h */
32 /* THE NONBLOCKING MYSQL API!
34 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
35 * that instead, you should thread your program. This is what i've done here to allow for
36 * asyncronous SQL requests via mysql. The way this works is as follows:
38 * The module spawns a thread via class Thread, and performs its mysql queries in this thread,
39 * using a queue with priorities. There is a mutex on either end which prevents two threads
40 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
41 * worker thread wakes up, and checks if there is a request at the head of its queue.
42 * If there is, it processes this request, blocking the worker thread but leaving the ircd
43 * thread to go about its business as usual. During this period, the ircd thread is able
44 * to insert futher pending requests into the queue.
46 * Once the processing of a request is complete, it is removed from the incoming queue to
47 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
48 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
49 * connection ID through the connection.
51 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
52 * of the queue, and sends it on its way to the original calling module.
54 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
55 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
56 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
57 * however, if we were to call a module's OnRequest even from within a thread which was not the
58 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
59 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
60 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
61 * gauranteed threadsafe!)
63 * For a diagram of this system please see http://wiki.inspircd.org/Mysql2
68 class DispatcherThread;
75 QQueueItem(SQLQuery* Q, const std::string& S, SQLConnection* C) : q(Q), query(S), c(C) {}
82 RQueueItem(SQLQuery* Q, MySQLresult* R) : q(Q), r(R) {}
85 typedef std::map<std::string, SQLConnection*> ConnMap;
86 typedef std::deque<QQueueItem> QueryQueue;
87 typedef std::deque<RQueueItem> ResultQueue;
91 class ModuleSQL : public Module
94 DispatcherThread* Dispatcher;
95 QueryQueue qq; // MUST HOLD MUTEX
96 ResultQueue rq; // MUST HOLD MUTEX
97 ConnMap connections; // main thread only
102 void OnRehash(User* user);
103 void OnUnloadModule(Module* mod);
104 Version GetVersion();
107 class DispatcherThread : public SocketThread
110 ModuleSQL* const Parent;
112 DispatcherThread(ModuleSQL* CreatorModule) : Parent(CreatorModule) { }
113 ~DispatcherThread() { }
115 virtual void OnNotify();
118 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
119 #define mysql_field_count mysql_num_fields
122 /** Represents a mysql result set
124 class MySQLresult : public SQLResult
130 std::vector<std::string> colnames;
131 std::vector<SQLEntries> fieldlists;
133 MySQLresult(MYSQL_RES* res, int affected_rows) : err(SQL_NO_ERROR), currentrow(0), rows(0)
135 if (affected_rows >= 1)
137 rows = affected_rows;
138 fieldlists.resize(rows);
140 unsigned int field_count = 0;
145 while ((row = mysql_fetch_row(res)))
147 if (fieldlists.size() < (unsigned int)rows+1)
149 fieldlists.resize(fieldlists.size()+1);
152 MYSQL_FIELD *fields = mysql_fetch_fields(res);
153 if(mysql_num_fields(res) == 0)
155 if (fields && mysql_num_fields(res))
158 while (field_count < mysql_num_fields(res))
160 std::string a = (fields[field_count].name ? fields[field_count].name : "");
161 if (row[field_count])
162 fieldlists[n].push_back(SQLEntry(row[field_count]));
164 fieldlists[n].push_back(SQLEntry());
165 colnames.push_back(a);
172 mysql_free_result(res);
177 MySQLresult(SQLerror& e) : err(e)
191 virtual void GetCols(std::vector<std::string>& result)
193 result.assign(colnames.begin(), colnames.end());
196 virtual SQLEntry GetValue(int row, int column)
198 if ((row >= 0) && (row < rows) && (column >= 0) && (column < (int)fieldlists[row].size()))
200 return fieldlists[row][column];
205 virtual bool GetRow(SQLEntries& result)
207 if (currentrow < rows)
209 result.assign(fieldlists[currentrow].begin(), fieldlists[currentrow].end());
221 /** Represents a connection to a mysql database
223 class SQLConnection : public SQLProvider
226 reference<ConfigTag> config;
230 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
231 SQLConnection(Module* p, ConfigTag* tag) : SQLProvider(p, "SQL/" + tag->getString("id")),
232 config(tag), connection(NULL)
241 // This method connects to the database using the credentials supplied to the constructor, and returns
242 // true upon success.
245 unsigned int timeout = 1;
246 connection = mysql_init(connection);
247 mysql_options(connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
248 std::string host = config->getString("host");
249 std::string user = config->getString("user");
250 std::string pass = config->getString("pass");
251 std::string dbname = config->getString("name");
252 int port = config->getInt("port");
253 bool rv = mysql_real_connect(connection, host.c_str(), user.c_str(), pass.c_str(), dbname.c_str(), port, NULL, 0);
256 std::string initquery;
257 if (config->readString("initialquery", initquery))
259 mysql_query(connection,initquery.c_str());
266 return (ModuleSQL*)(Module*)creator;
269 MySQLresult* DoBlockingQuery(const std::string& query)
272 /* Parse the command string and dispatch it to mysql */
273 if (CheckConnection() && !mysql_real_query(connection, query.data(), query.length()))
275 /* Successfull query */
276 MYSQL_RES* res = mysql_use_result(connection);
277 unsigned long rows = mysql_affected_rows(connection);
278 return new MySQLresult(res, rows);
282 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
283 * possible error numbers and error messages */
284 SQLerror e(SQL_QREPLY_FAIL, ConvToStr(mysql_errno(connection)) + std::string(": ") + mysql_error(connection));
285 return new MySQLresult(e);
289 bool CheckConnection()
291 if (!connection || mysql_ping(connection) != 0)
296 std::string GetError()
298 return mysql_error(connection);
303 mysql_close(connection);
306 void submit(SQLQuery* q, const std::string& qs)
308 Parent()->Dispatcher->LockQueue();
309 Parent()->qq.push_back(QQueueItem(q, qs, this));
310 Parent()->Dispatcher->UnlockQueueWakeup();
313 void submit(SQLQuery* call, const std::string& q, const ParamL& p)
316 unsigned int param = 0;
317 for(std::string::size_type i = 0; i < q.length(); i++)
323 if (param < p.size())
325 std::string parm = p[param++];
327 mysql_escape_string(buffer, parm.c_str(), parm.length());
328 // mysql_real_escape_string(connection, queryend, paramscopy[paramnum].c_str(), paramscopy[paramnum].length());
336 void submit(SQLQuery* call, const std::string& q, const ParamM& p)
339 for(std::string::size_type i = 0; i < q.length(); i++)
347 while (i < q.length() && isalpha(q[i]))
348 field.push_back(q[i++]);
351 ParamM::const_iterator it = p.find(field);
354 std::string parm = it->second;
356 mysql_escape_string(buffer, parm.c_str(), parm.length());
365 ModuleSQL::ModuleSQL()
370 void ModuleSQL::init()
372 Dispatcher = new DispatcherThread(this);
373 ServerInstance->Threads->Start(Dispatcher);
375 Implementation eventlist[] = { I_OnRehash, I_OnUnloadModule };
376 ServerInstance->Modules->Attach(eventlist, this, 2);
381 ModuleSQL::~ModuleSQL()
386 Dispatcher->OnNotify();
389 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
395 void ModuleSQL::OnRehash(User* user)
398 ConfigTagList tags = ServerInstance->Config->ConfTags("database");
399 for(ConfigIter i = tags.first; i != tags.second; i++)
401 if (i->second->getString("module", "mysql") != "mysql")
403 std::string id = i->second->getString("id");
404 ConnMap::iterator curr = connections.find(id);
405 if (curr == connections.end())
407 SQLConnection* conn = new SQLConnection(this, i->second);
408 conns.insert(std::make_pair(id, conn));
409 ServerInstance->Modules->AddService(*conn);
414 connections.erase(curr);
418 // now clean up the deleted databases
419 Dispatcher->LockQueue();
420 SQLerror err(SQL_BAD_DBID);
421 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
423 ServerInstance->Modules->DelService(*i->second);
424 // it might be running a query on this database. Wait for that to complete
425 i->second->lock.Lock();
426 i->second->lock.Unlock();
427 // now remove all active queries to this DB
428 for(unsigned int j = qq.size() - 1; j >= 0; j--)
430 if (qq[j].c == i->second)
432 qq[j].q->OnError(err);
434 qq.erase(qq.begin() + j);
437 // finally, nuke the connection
440 Dispatcher->UnlockQueue();
441 connections.swap(conns);
444 void ModuleSQL::OnUnloadModule(Module* mod)
446 SQLerror err(SQL_BAD_DBID);
447 Dispatcher->LockQueue();
448 for(unsigned int i = qq.size() - 1; i >= 0; i--)
450 if (qq[i].q->creator == mod)
454 // need to wait until the query is done
455 // (the result will be discarded)
456 qq[i].c->lock.Lock();
457 qq[i].c->lock.Unlock();
459 qq[i].q->OnError(err);
461 qq.erase(qq.begin() + i);
464 Dispatcher->UnlockQueue();
465 // clean up any result queue entries
466 Dispatcher->OnNotify();
469 Version ModuleSQL::GetVersion()
471 return Version("MySQL support", VF_VENDOR);
474 void DispatcherThread::Run()
477 while (!this->GetExitFlag())
479 if (!Parent->qq.empty())
481 QQueueItem i = Parent->qq.front();
484 MySQLresult* res = i.c->DoBlockingQuery(i.query);
488 * At this point, the main thread could be working on:
489 * Rehash - delete i.c out from under us. We don't care about that.
490 * UnloadModule - delete i.q and the qq item. Need to avoid reporting results.
494 if (Parent->qq.front().q == i.q)
496 Parent->qq.pop_front();
497 Parent->rq.push_back(RQueueItem(i.q, res));
502 // UnloadModule ate the query
508 /* We know the queue is empty, we can safely hang this thread until
511 this->WaitForQueue();
517 void DispatcherThread::OnNotify()
519 // this could unlock during the dispatch, but OnResult isn't expected to take that long
521 for(ResultQueue::iterator i = Parent->rq.begin(); i != Parent->rq.end(); i++)
523 MySQLresult* res = i->r;
524 if (res->err.id == SQL_NO_ERROR)
525 i->q->OnResult(*res);
527 i->q->OnError(res->err);
535 MODULE_INIT(ModuleSQL)