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 // Fix warnings about the use of `long long` on C++03.
25 # pragma clang diagnostic ignored "-Wc++11-long-long"
26 #elif defined __GNUC__
27 # pragma GCC diagnostic ignored "-Wlong-long"
32 #include "modules/sql.h"
35 # pragma comment(lib, "libmysql.lib")
38 /* VERSION 3 API: With nonblocking (threaded) requests */
40 /* $CompileFlags: exec("mysql_config --include") */
41 /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */
43 /* THE NONBLOCKING MYSQL API!
45 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
46 * that instead, you should thread your program. This is what i've done here to allow for
47 * asyncronous SQL requests via mysql. The way this works is as follows:
49 * The module spawns a thread via class Thread, and performs its mysql queries in this thread,
50 * using a queue with priorities. There is a mutex on either end which prevents two threads
51 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
52 * worker thread wakes up, and checks if there is a request at the head of its queue.
53 * If there is, it processes this request, blocking the worker thread but leaving the ircd
54 * thread to go about its business as usual. During this period, the ircd thread is able
55 * to insert futher pending requests into the queue.
57 * Once the processing of a request is complete, it is removed from the incoming queue to
58 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
59 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
60 * connection ID through the connection.
62 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
63 * of the queue, and sends it on its way to the original calling module.
65 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
66 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
67 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
68 * however, if we were to call a module's OnRequest even from within a thread which was not the
69 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
70 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
71 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
72 * gauranteed threadsafe!)
74 * For a diagram of this system please see http://wiki.inspircd.org/Mysql2
79 class DispatcherThread;
86 QQueueItem(SQLQuery* Q, const std::string& S, SQLConnection* C) : q(Q), query(S), c(C) {}
93 RQueueItem(SQLQuery* Q, MySQLresult* R) : q(Q), r(R) {}
96 typedef insp::flat_map<std::string, SQLConnection*> ConnMap;
97 typedef std::deque<QQueueItem> QueryQueue;
98 typedef std::deque<RQueueItem> ResultQueue;
102 class ModuleSQL : public Module
105 DispatcherThread* Dispatcher;
106 QueryQueue qq; // MUST HOLD MUTEX
107 ResultQueue rq; // MUST HOLD MUTEX
108 ConnMap connections; // main thread only
111 void init() CXX11_OVERRIDE;
113 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE;
114 void OnUnloadModule(Module* mod) CXX11_OVERRIDE;
115 Version GetVersion() CXX11_OVERRIDE;
118 class DispatcherThread : public SocketThread
121 ModuleSQL* const Parent;
123 DispatcherThread(ModuleSQL* CreatorModule) : Parent(CreatorModule) { }
124 ~DispatcherThread() { }
129 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
130 #define mysql_field_count mysql_num_fields
133 /** Represents a mysql result set
135 class MySQLresult : public SQLResult
141 std::vector<std::string> colnames;
142 std::vector<SQLEntries> fieldlists;
144 MySQLresult(MYSQL_RES* res, int affected_rows) : err(SQL_NO_ERROR), currentrow(0), rows(0)
146 if (affected_rows >= 1)
148 rows = affected_rows;
149 fieldlists.resize(rows);
151 unsigned int field_count = 0;
156 while ((row = mysql_fetch_row(res)))
158 if (fieldlists.size() < (unsigned int)rows+1)
160 fieldlists.resize(fieldlists.size()+1);
163 MYSQL_FIELD *fields = mysql_fetch_fields(res);
164 if(mysql_num_fields(res) == 0)
166 if (fields && mysql_num_fields(res))
169 while (field_count < mysql_num_fields(res))
171 std::string a = (fields[field_count].name ? fields[field_count].name : "");
172 if (row[field_count])
173 fieldlists[n].push_back(SQLEntry(row[field_count]));
175 fieldlists[n].push_back(SQLEntry());
176 colnames.push_back(a);
183 mysql_free_result(res);
187 MySQLresult(SQLerror& e) : err(e)
197 void GetCols(std::vector<std::string>& result)
199 result.assign(colnames.begin(), colnames.end());
202 SQLEntry GetValue(int row, int column)
204 if ((row >= 0) && (row < rows) && (column >= 0) && (column < (int)fieldlists[row].size()))
206 return fieldlists[row][column];
211 bool GetRow(SQLEntries& result)
213 if (currentrow < rows)
215 result.assign(fieldlists[currentrow].begin(), fieldlists[currentrow].end());
227 /** Represents a connection to a mysql database
229 class SQLConnection : public SQLProvider
232 reference<ConfigTag> config;
236 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
237 SQLConnection(Module* p, ConfigTag* tag) : SQLProvider(p, "SQL/" + tag->getString("id")),
238 config(tag), connection(NULL)
247 // This method connects to the database using the credentials supplied to the constructor, and returns
248 // true upon success.
251 unsigned int timeout = 1;
252 connection = mysql_init(connection);
253 mysql_options(connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
254 std::string host = config->getString("host");
255 std::string user = config->getString("user");
256 std::string pass = config->getString("pass");
257 std::string dbname = config->getString("name");
258 int port = config->getInt("port");
259 bool rv = mysql_real_connect(connection, host.c_str(), user.c_str(), pass.c_str(), dbname.c_str(), port, NULL, 0);
263 // Enable character set settings
264 std::string charset = config->getString("charset");
265 if ((!charset.empty()) && (mysql_set_character_set(connection, charset.c_str())))
266 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WARNING: Could not set character set to \"%s\"", charset.c_str());
268 std::string initquery;
269 if (config->readString("initialquery", initquery))
271 mysql_query(connection,initquery.c_str());
278 return (ModuleSQL*)(Module*)creator;
281 MySQLresult* DoBlockingQuery(const std::string& query)
284 /* Parse the command string and dispatch it to mysql */
285 if (CheckConnection() && !mysql_real_query(connection, query.data(), query.length()))
287 /* Successfull query */
288 MYSQL_RES* res = mysql_use_result(connection);
289 unsigned long rows = mysql_affected_rows(connection);
290 return new MySQLresult(res, rows);
294 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
295 * possible error numbers and error messages */
296 SQLerror e(SQL_QREPLY_FAIL, ConvToStr(mysql_errno(connection)) + ": " + mysql_error(connection));
297 return new MySQLresult(e);
301 bool CheckConnection()
303 if (!connection || mysql_ping(connection) != 0)
308 std::string GetError()
310 return mysql_error(connection);
315 mysql_close(connection);
318 void submit(SQLQuery* q, const std::string& qs)
320 Parent()->Dispatcher->LockQueue();
321 Parent()->qq.push_back(QQueueItem(q, qs, this));
322 Parent()->Dispatcher->UnlockQueueWakeup();
325 void submit(SQLQuery* call, const std::string& q, const ParamL& p)
328 unsigned int param = 0;
329 for(std::string::size_type i = 0; i < q.length(); i++)
335 if (param < p.size())
337 std::string parm = p[param++];
338 // In the worst case, each character may need to be encoded as using two bytes,
339 // and one byte is the terminating null
340 std::vector<char> buffer(parm.length() * 2 + 1);
342 // The return value of mysql_escape_string() is the length of the encoded string,
343 // not including the terminating null
344 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
345 // mysql_real_escape_string(connection, queryend, paramscopy[paramnum].c_str(), paramscopy[paramnum].length());
346 res.append(&buffer[0], escapedsize);
353 void submit(SQLQuery* call, const std::string& q, const ParamM& p)
356 for(std::string::size_type i = 0; i < q.length(); i++)
364 while (i < q.length() && isalnum(q[i]))
365 field.push_back(q[i++]);
368 ParamM::const_iterator it = p.find(field);
371 std::string parm = it->second;
373 std::vector<char> buffer(parm.length() * 2 + 1);
374 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
375 res.append(&buffer[0], escapedsize);
383 ModuleSQL::ModuleSQL()
388 void ModuleSQL::init()
390 Dispatcher = new DispatcherThread(this);
391 ServerInstance->Threads.Start(Dispatcher);
394 ModuleSQL::~ModuleSQL()
399 Dispatcher->OnNotify();
402 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
408 void ModuleSQL::ReadConfig(ConfigStatus& status)
411 ConfigTagList tags = ServerInstance->Config->ConfTags("database");
412 for(ConfigIter i = tags.first; i != tags.second; i++)
414 if (i->second->getString("module", "mysql") != "mysql")
416 std::string id = i->second->getString("id");
417 ConnMap::iterator curr = connections.find(id);
418 if (curr == connections.end())
420 SQLConnection* conn = new SQLConnection(this, i->second);
421 conns.insert(std::make_pair(id, conn));
422 ServerInstance->Modules->AddService(*conn);
427 connections.erase(curr);
431 // now clean up the deleted databases
432 Dispatcher->LockQueue();
433 SQLerror err(SQL_BAD_DBID);
434 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
436 ServerInstance->Modules->DelService(*i->second);
437 // it might be running a query on this database. Wait for that to complete
438 i->second->lock.Lock();
439 i->second->lock.Unlock();
440 // now remove all active queries to this DB
441 for (size_t j = qq.size(); j > 0; j--)
444 if (qq[k].c == i->second)
446 qq[k].q->OnError(err);
448 qq.erase(qq.begin() + k);
451 // finally, nuke the connection
454 Dispatcher->UnlockQueue();
455 connections.swap(conns);
458 void ModuleSQL::OnUnloadModule(Module* mod)
460 SQLerror err(SQL_BAD_DBID);
461 Dispatcher->LockQueue();
462 unsigned int i = qq.size();
466 if (qq[i].q->creator == mod)
470 // need to wait until the query is done
471 // (the result will be discarded)
472 qq[i].c->lock.Lock();
473 qq[i].c->lock.Unlock();
475 qq[i].q->OnError(err);
477 qq.erase(qq.begin() + i);
480 Dispatcher->UnlockQueue();
481 // clean up any result queue entries
482 Dispatcher->OnNotify();
485 Version ModuleSQL::GetVersion()
487 return Version("MySQL support", VF_VENDOR);
490 void DispatcherThread::Run()
493 while (!this->GetExitFlag())
495 if (!Parent->qq.empty())
497 QQueueItem i = Parent->qq.front();
500 MySQLresult* res = i.c->DoBlockingQuery(i.query);
504 * At this point, the main thread could be working on:
505 * Rehash - delete i.c out from under us. We don't care about that.
506 * UnloadModule - delete i.q and the qq item. Need to avoid reporting results.
510 if (!Parent->qq.empty() && Parent->qq.front().q == i.q)
512 Parent->qq.pop_front();
513 Parent->rq.push_back(RQueueItem(i.q, res));
518 // UnloadModule ate the query
524 /* We know the queue is empty, we can safely hang this thread until
527 this->WaitForQueue();
533 void DispatcherThread::OnNotify()
535 // this could unlock during the dispatch, but OnResult isn't expected to take that long
537 for(ResultQueue::iterator i = Parent->rq.begin(); i != Parent->rq.end(); i++)
539 MySQLresult* res = i->r;
540 if (res->err.id == SQL_NO_ERROR)
541 i->q->OnResult(*res);
543 i->q->OnError(res->err);
551 MODULE_INIT(ModuleSQL)