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
28 #include "modules/sql.h"
31 # pragma comment(lib, "libmysql.lib")
34 /* VERSION 3 API: With nonblocking (threaded) requests */
36 /* $CompileFlags: exec("mysql_config --include") */
37 /* $LinkerFlags: exec("mysql_config --libs_r") rpath("mysql_config --libs_r") */
39 /* THE NONBLOCKING MYSQL API!
41 * MySQL provides no nonblocking (asyncronous) API of its own, and its developers recommend
42 * that instead, you should thread your program. This is what i've done here to allow for
43 * asyncronous SQL requests via mysql. The way this works is as follows:
45 * The module spawns a thread via class Thread, and performs its mysql queries in this thread,
46 * using a queue with priorities. There is a mutex on either end which prevents two threads
47 * adjusting the queue at the same time, and crashing the ircd. Every 50 milliseconds, the
48 * worker thread wakes up, and checks if there is a request at the head of its queue.
49 * If there is, it processes this request, blocking the worker thread but leaving the ircd
50 * thread to go about its business as usual. During this period, the ircd thread is able
51 * to insert futher pending requests into the queue.
53 * Once the processing of a request is complete, it is removed from the incoming queue to
54 * an outgoing queue, and initialized as a 'response'. The worker thread then signals the
55 * ircd thread (via a loopback socket) of the fact a result is available, by sending the
56 * connection ID through the connection.
58 * The ircd thread then mutexes the queue once more, reads the outbound response off the head
59 * of the queue, and sends it on its way to the original calling module.
61 * XXX: You might be asking "why doesnt he just send the response from within the worker thread?"
62 * The answer to this is simple. The majority of InspIRCd, and in fact most ircd's are not
63 * threadsafe. This module is designed to be threadsafe and is careful with its use of threads,
64 * however, if we were to call a module's OnRequest even from within a thread which was not the
65 * one the module was originally instantiated upon, there is a chance of all hell breaking loose
66 * if a module is ever put in a re-enterant state (stack corruption could occur, crashes, data
67 * corruption, and worse, so DONT think about it until the day comes when InspIRCd is 100%
68 * gauranteed threadsafe!)
70 * For a diagram of this system please see http://wiki.inspircd.org/Mysql2
75 class DispatcherThread;
82 QQueueItem(SQLQuery* Q, const std::string& S, SQLConnection* C) : q(Q), query(S), c(C) {}
89 RQueueItem(SQLQuery* Q, MySQLresult* R) : q(Q), r(R) {}
92 typedef insp::flat_map<std::string, SQLConnection*> ConnMap;
93 typedef std::deque<QQueueItem> QueryQueue;
94 typedef std::deque<RQueueItem> ResultQueue;
98 class ModuleSQL : public Module
101 DispatcherThread* Dispatcher;
102 QueryQueue qq; // MUST HOLD MUTEX
103 ResultQueue rq; // MUST HOLD MUTEX
104 ConnMap connections; // main thread only
107 void init() CXX11_OVERRIDE;
109 void ReadConfig(ConfigStatus& status) CXX11_OVERRIDE;
110 void OnUnloadModule(Module* mod) CXX11_OVERRIDE;
111 Version GetVersion() CXX11_OVERRIDE;
114 class DispatcherThread : public SocketThread
117 ModuleSQL* const Parent;
119 DispatcherThread(ModuleSQL* CreatorModule) : Parent(CreatorModule) { }
120 ~DispatcherThread() { }
125 #if !defined(MYSQL_VERSION_ID) || MYSQL_VERSION_ID<32224
126 #define mysql_field_count mysql_num_fields
129 /** Represents a mysql result set
131 class MySQLresult : public SQLResult
137 std::vector<std::string> colnames;
138 std::vector<SQLEntries> fieldlists;
140 MySQLresult(MYSQL_RES* res, int affected_rows) : err(SQL_NO_ERROR), currentrow(0), rows(0)
142 if (affected_rows >= 1)
144 rows = affected_rows;
145 fieldlists.resize(rows);
147 unsigned int field_count = 0;
152 while ((row = mysql_fetch_row(res)))
154 if (fieldlists.size() < (unsigned int)rows+1)
156 fieldlists.resize(fieldlists.size()+1);
159 MYSQL_FIELD *fields = mysql_fetch_fields(res);
160 if(mysql_num_fields(res) == 0)
162 if (fields && mysql_num_fields(res))
165 while (field_count < mysql_num_fields(res))
167 std::string a = (fields[field_count].name ? fields[field_count].name : "");
168 if (row[field_count])
169 fieldlists[n].push_back(SQLEntry(row[field_count]));
171 fieldlists[n].push_back(SQLEntry());
172 colnames.push_back(a);
179 mysql_free_result(res);
183 MySQLresult(SQLerror& e) : err(e)
193 void GetCols(std::vector<std::string>& result)
195 result.assign(colnames.begin(), colnames.end());
198 SQLEntry GetValue(int row, int column)
200 if ((row >= 0) && (row < rows) && (column >= 0) && (column < (int)fieldlists[row].size()))
202 return fieldlists[row][column];
207 bool GetRow(SQLEntries& result)
209 if (currentrow < rows)
211 result.assign(fieldlists[currentrow].begin(), fieldlists[currentrow].end());
223 /** Represents a connection to a mysql database
225 class SQLConnection : public SQLProvider
228 reference<ConfigTag> config;
232 // This constructor creates an SQLConnection object with the given credentials, but does not connect yet.
233 SQLConnection(Module* p, ConfigTag* tag) : SQLProvider(p, "SQL/" + tag->getString("id")),
234 config(tag), connection(NULL)
243 // This method connects to the database using the credentials supplied to the constructor, and returns
244 // true upon success.
247 unsigned int timeout = 1;
248 connection = mysql_init(connection);
249 mysql_options(connection,MYSQL_OPT_CONNECT_TIMEOUT,(char*)&timeout);
250 std::string host = config->getString("host");
251 std::string user = config->getString("user");
252 std::string pass = config->getString("pass");
253 std::string dbname = config->getString("name");
254 int port = config->getInt("port");
255 bool rv = mysql_real_connect(connection, host.c_str(), user.c_str(), pass.c_str(), dbname.c_str(), port, NULL, 0);
259 // Enable character set settings
260 std::string charset = config->getString("charset");
261 if ((!charset.empty()) && (mysql_set_character_set(connection, charset.c_str())))
262 ServerInstance->Logs->Log(MODNAME, LOG_DEFAULT, "WARNING: Could not set character set to \"%s\"", charset.c_str());
264 std::string initquery;
265 if (config->readString("initialquery", initquery))
267 mysql_query(connection,initquery.c_str());
274 return (ModuleSQL*)(Module*)creator;
277 MySQLresult* DoBlockingQuery(const std::string& query)
280 /* Parse the command string and dispatch it to mysql */
281 if (CheckConnection() && !mysql_real_query(connection, query.data(), query.length()))
283 /* Successfull query */
284 MYSQL_RES* res = mysql_use_result(connection);
285 unsigned long rows = mysql_affected_rows(connection);
286 return new MySQLresult(res, rows);
290 /* XXX: See /usr/include/mysql/mysqld_error.h for a list of
291 * possible error numbers and error messages */
292 SQLerror e(SQL_QREPLY_FAIL, ConvToStr(mysql_errno(connection)) + ": " + mysql_error(connection));
293 return new MySQLresult(e);
297 bool CheckConnection()
299 if (!connection || mysql_ping(connection) != 0)
304 std::string GetError()
306 return mysql_error(connection);
311 mysql_close(connection);
314 void submit(SQLQuery* q, const std::string& qs)
316 Parent()->Dispatcher->LockQueue();
317 Parent()->qq.push_back(QQueueItem(q, qs, this));
318 Parent()->Dispatcher->UnlockQueueWakeup();
321 void submit(SQLQuery* call, const std::string& q, const ParamL& p)
324 unsigned int param = 0;
325 for(std::string::size_type i = 0; i < q.length(); i++)
331 if (param < p.size())
333 std::string parm = p[param++];
334 // In the worst case, each character may need to be encoded as using two bytes,
335 // and one byte is the terminating null
336 std::vector<char> buffer(parm.length() * 2 + 1);
338 // The return value of mysql_escape_string() is the length of the encoded string,
339 // not including the terminating null
340 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
341 // mysql_real_escape_string(connection, queryend, paramscopy[paramnum].c_str(), paramscopy[paramnum].length());
342 res.append(&buffer[0], escapedsize);
349 void submit(SQLQuery* call, const std::string& q, const ParamM& p)
352 for(std::string::size_type i = 0; i < q.length(); i++)
360 while (i < q.length() && isalnum(q[i]))
361 field.push_back(q[i++]);
364 ParamM::const_iterator it = p.find(field);
367 std::string parm = it->second;
369 std::vector<char> buffer(parm.length() * 2 + 1);
370 unsigned long escapedsize = mysql_escape_string(&buffer[0], parm.c_str(), parm.length());
371 res.append(&buffer[0], escapedsize);
379 ModuleSQL::ModuleSQL()
384 void ModuleSQL::init()
386 Dispatcher = new DispatcherThread(this);
387 ServerInstance->Threads.Start(Dispatcher);
390 ModuleSQL::~ModuleSQL()
395 Dispatcher->OnNotify();
398 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
404 void ModuleSQL::ReadConfig(ConfigStatus& status)
407 ConfigTagList tags = ServerInstance->Config->ConfTags("database");
408 for(ConfigIter i = tags.first; i != tags.second; i++)
410 if (i->second->getString("module", "mysql") != "mysql")
412 std::string id = i->second->getString("id");
413 ConnMap::iterator curr = connections.find(id);
414 if (curr == connections.end())
416 SQLConnection* conn = new SQLConnection(this, i->second);
417 conns.insert(std::make_pair(id, conn));
418 ServerInstance->Modules->AddService(*conn);
423 connections.erase(curr);
427 // now clean up the deleted databases
428 Dispatcher->LockQueue();
429 SQLerror err(SQL_BAD_DBID);
430 for(ConnMap::iterator i = connections.begin(); i != connections.end(); i++)
432 ServerInstance->Modules->DelService(*i->second);
433 // it might be running a query on this database. Wait for that to complete
434 i->second->lock.Lock();
435 i->second->lock.Unlock();
436 // now remove all active queries to this DB
437 for (size_t j = qq.size(); j > 0; j--)
440 if (qq[k].c == i->second)
442 qq[k].q->OnError(err);
444 qq.erase(qq.begin() + k);
447 // finally, nuke the connection
450 Dispatcher->UnlockQueue();
451 connections.swap(conns);
454 void ModuleSQL::OnUnloadModule(Module* mod)
456 SQLerror err(SQL_BAD_DBID);
457 Dispatcher->LockQueue();
458 unsigned int i = qq.size();
462 if (qq[i].q->creator == mod)
466 // need to wait until the query is done
467 // (the result will be discarded)
468 qq[i].c->lock.Lock();
469 qq[i].c->lock.Unlock();
471 qq[i].q->OnError(err);
473 qq.erase(qq.begin() + i);
476 Dispatcher->UnlockQueue();
477 // clean up any result queue entries
478 Dispatcher->OnNotify();
481 Version ModuleSQL::GetVersion()
483 return Version("MySQL support", VF_VENDOR);
486 void DispatcherThread::Run()
489 while (!this->GetExitFlag())
491 if (!Parent->qq.empty())
493 QQueueItem i = Parent->qq.front();
496 MySQLresult* res = i.c->DoBlockingQuery(i.query);
500 * At this point, the main thread could be working on:
501 * Rehash - delete i.c out from under us. We don't care about that.
502 * UnloadModule - delete i.q and the qq item. Need to avoid reporting results.
506 if (!Parent->qq.empty() && Parent->qq.front().q == i.q)
508 Parent->qq.pop_front();
509 Parent->rq.push_back(RQueueItem(i.q, res));
514 // UnloadModule ate the query
520 /* We know the queue is empty, we can safely hang this thread until
523 this->WaitForQueue();
529 void DispatcherThread::OnNotify()
531 // this could unlock during the dispatch, but OnResult isn't expected to take that long
533 for(ResultQueue::iterator i = Parent->rq.begin(); i != Parent->rq.end(); i++)
535 MySQLresult* res = i->r;
536 if (res->err.id == SQL_NO_ERROR)
537 i->q->OnResult(*res);
539 i->q->OnError(res->err);
547 MODULE_INIT(ModuleSQL)