src/modules/m_permchannels.cpp

   1 /*
   2  * InspIRCd -- Internet Relay Chat Daemon
   3  *
   4  *   Copyright (C) 2009-2010 Daniel De Graaf <danieldg@inspircd.org>
   5  *   Copyright (C) 2008-2009 Robin Burchell <robin+git@viroteck.net>
   6  *
   7  * This file is part of InspIRCd.  InspIRCd is free software: you can
   8  * redistribute it and/or modify it under the terms of the GNU General Public
   9  * License as published by the Free Software Foundation, version 2.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  13  * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
  14  * details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20
  21 #include "inspircd.h"
  22 #include <fstream>
  23
  24 /* $ModDesc: Provides support for channel mode +P to provide permanent channels */
  25
  26 // Not in a class due to circular dependancy hell.
  27 static std::string permchannelsconf;
  28 static bool WriteDatabase()
  29 {
  30         /*
  31          * We need to perform an atomic write so as not to fuck things up.
  32          * So, let's write to a temporary file, flush it, then rename the file..
  33          *     -- w00t
  34          */
  35
  36         // If the user has not specified a configuration file then we don't write one.
  37         if (permchannelsconf.empty())
  38                 return true;
  39
  40         std::string permchannelsnewconf = permchannelsconf + ".tmp";
  41         std::ofstream stream(permchannelsnewconf.c_str());
  42         if (!stream.is_open())
  43         {
  44                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot create database! %s (%d)", strerror(errno), errno);
  45                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot create new db: %s (%d)", strerror(errno), errno);
  46                 return false;
  47         }
  48
  49         stream << "# This file is automatically generated by m_permchannels. Any changes will be overwritten." << std::endl
  50                 << "<config format=\"xml\">" << std::endl;
  51
  52         for (chan_hash::const_iterator i = ServerInstance->chanlist->begin(); i != ServerInstance->chanlist->end(); i++)
  53         {
  54                 Channel* chan = i->second;
  55                 if (!chan->IsModeSet('P'))
  56                         continue;
  57
  58                 stream << "<permchannels channel=\"" << ServerConfig::Escape(chan->name)
  59                         << "\" topic=\"" << ServerConfig::Escape(chan->topic)
  60                         << "\" modes=\"" << ServerConfig::Escape(chan->ChanModes(true))
  61                         << "\">" << std::endl;
  62         }
  63
  64         if (stream.fail())
  65         {
  66                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot write to new database! %s (%d)", strerror(errno), errno);
  67                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot write to new db: %s (%d)", strerror(errno), errno);
  68                 return false;
  69         }
  70         stream.close();
  71
  72 #ifdef _WIN32
  73         if (remove(permchannelsconf.c_str()))
  74         {
  75                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot remove old database! %s (%d)", strerror(errno), errno);
  76                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot remove old database: %s (%d)", strerror(errno), errno);
  77                 return false;
  78         }
  79 #endif
  80         // Use rename to move temporary to new db - this is guarenteed not to fuck up, even in case of a crash.
  81         if (rename(permchannelsnewconf.c_str(), permchannelsconf.c_str()) < 0)
  82         {
  83                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot move new to old database! %s (%d)", strerror(errno), errno);
  84                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot replace old with new db: %s (%d)", strerror(errno), errno);
  85                 return false;
  86         }
  87
  88         return true;
  89 }
  90
  91
  92 /** Handles the +P channel mode
  93  */
  94 class PermChannel : public ModeHandler
  95 {
  96  public:
  97         PermChannel(Module* Creator) : ModeHandler(Creator, "permanent", 'P', PARAM_NONE, MODETYPE_CHANNEL) { oper = true; }
  98
  99         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 100         {
 101                 if (adding)
 102                 {
 103                         if (!channel->IsModeSet('P'))
 104                         {
 105                                 channel->SetMode('P',true);
 106                                 return MODEACTION_ALLOW;
 107                         }
 108                 }
 109                 else
 110                 {
 111                         if (channel->IsModeSet('P'))
 112                         {
 113                                 channel->SetMode(this,false);
 114                                 channel->CheckDestroy();
 115                                 return MODEACTION_ALLOW;
 116                         }
 117                 }
 118
 119                 return MODEACTION_DENY;
 120         }
 121 };
 122
 123 class ModulePermanentChannels : public Module
 124 {
 125         PermChannel p;
 126         bool dirty;
 127 public:
 128
 129         ModulePermanentChannels() : p(this), dirty(false)
 130         {
 131         }
 132
 133         void init() CXX11_OVERRIDE
 134         {
 135                 ServerInstance->Modules->AddService(p);
 136                 Implementation eventlist[] = { I_OnChannelPreDelete, I_OnPostTopicChange, I_OnRawMode, I_OnRehash, I_OnBackgroundTimer };
 137                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 138
 139                 OnRehash(NULL);
 140         }
 141
 142         CullResult cull()
 143         {
 144                 /*
 145                  * DelMode can't remove the +P mode on empty channels, or it will break
 146                  * merging modes with remote servers. Remove the empty channels now as
 147                  * we know this is not the case.
 148                  */
 149                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 150                 while (iter != ServerInstance->chanlist->end())
 151                 {
 152                         Channel* c = iter->second;
 153                         if (c->GetUserCounter() == 0)
 154                         {
 155                                 chan_hash::iterator at = iter;
 156                                 iter++;
 157                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 158                                 ServerInstance->chanlist->erase(at);
 159                                 ServerInstance->GlobalCulls.AddItem(c);
 160                         }
 161                         else
 162                                 iter++;
 163                 }
 164                 ServerInstance->Modes->DelMode(&p);
 165                 return Module::cull();
 166         }
 167
 168         void OnRehash(User *user) CXX11_OVERRIDE
 169         {
 170                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 171         }
 172
 173         void LoadDatabase()
 174         {
 175                 /*
 176                  * Process config-defined list of permanent channels.
 177                  * -- w00t
 178                  */
 179                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 180                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 181                 {
 182                         ConfigTag* tag = i->second;
 183                         std::string channel = tag->getString("channel");
 184                         std::string topic = tag->getString("topic");
 185                         std::string modes = tag->getString("modes");
 186
 187                         if (channel.empty())
 188                         {
 189                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Malformed permchannels tag with empty channel name.");
 190                                 continue;
 191                         }
 192
 193                         Channel *c = ServerInstance->FindChan(channel);
 194
 195                         if (!c)
 196                         {
 197                                 c = new Channel(channel, ServerInstance->Time());
 198                                 if (!topic.empty())
 199                                 {
 200                                         c->SetTopic(ServerInstance->FakeClient, topic, true);
 201
 202                                         /*
 203                                          * Due to the way protocol works in 1.2, we need to hack the topic TS in such a way that this
 204                                          * topic will always win over others.
 205                                          *
 206                                          * This is scheduled for (proper) fixing in a later release, and can be removed at a later date.
 207                                          */
 208                                         c->topicset = 42;
 209                                 }
 210                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Added %s with topic %s", channel.c_str(), topic.c_str());
 211
 212                                 if (modes.empty())
 213                                         continue;
 214
 215                                 irc::spacesepstream list(modes);
 216                                 std::string modeseq;
 217                                 std::string par;
 218
 219                                 list.GetToken(modeseq);
 220
 221                                 // XXX bleh, should we pass this to the mode parser instead? ugly. --w00t
 222                                 for (std::string::iterator n = modeseq.begin(); n != modeseq.end(); ++n)
 223                                 {
 224                                         ModeHandler* mode = ServerInstance->Modes->FindMode(*n, MODETYPE_CHANNEL);
 225                                         if (mode)
 226                                         {
 227                                                 if (mode->GetNumParams(true))
 228                                                         list.GetToken(par);
 229                                                 else
 230                                                         par.clear();
 231
 232                                                 mode->OnModeChange(ServerInstance->FakeClient, ServerInstance->FakeClient, c, par, true);
 233                                         }
 234                                 }
 235                         }
 236                 }
 237         }
 238
 239         ModResult OnRawMode(User* user, Channel* chan, const char mode, const std::string &param, bool adding, int pcnt) CXX11_OVERRIDE
 240         {
 241                 if (chan && (chan->IsModeSet('P') || mode == 'P'))
 242                         dirty = true;
 243
 244                 return MOD_RES_PASSTHRU;
 245         }
 246
 247         void OnPostTopicChange(User*, Channel *c, const std::string&) CXX11_OVERRIDE
 248         {
 249                 if (c->IsModeSet('P'))
 250                         dirty = true;
 251         }
 252
 253         void OnBackgroundTimer(time_t) CXX11_OVERRIDE
 254         {
 255                 if (dirty)
 256                         WriteDatabase();
 257                 dirty = false;
 258         }
 259
 260         void Prioritize()
 261         {
 262                 // XXX: Load the DB here because the order in which modules are init()ed at boot is
 263                 // alphabetical, this means we must wait until all modules have done their init()
 264                 // to be able to set the modes they provide (e.g.: m_stripcolor is inited after us)
 265                 // Prioritize() is called after all module initialization is complete, consequently
 266                 // all modes are available now
 267
 268                 static bool loaded = false;
 269                 if (loaded)
 270                         return;
 271
 272                 loaded = true;
 273
 274                 // Load only when there are no linked servers - we set the TS of the channels we
 275                 // create to the current time, this can lead to desync because spanningtree has
 276                 // no way of knowing what we do
 277                 ProtoServerList serverlist;
 278                 ServerInstance->PI->GetServerList(serverlist);
 279                 if (serverlist.size() < 2)
 280                 {
 281                         try
 282                         {
 283                                 LoadDatabase();
 284                         }
 285                         catch (CoreException& e)
 286                         {
 287                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "Error loading permchannels database: " + std::string(e.GetReason()));
 288                         }
 289                 }
 290         }
 291
 292         Version GetVersion() CXX11_OVERRIDE
 293         {
 294                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 295         }
 296
 297         ModResult OnChannelPreDelete(Channel *c) CXX11_OVERRIDE
 298         {
 299                 if (c->IsModeSet('P'))
 300                         return MOD_RES_DENY;
 301
 302                 return MOD_RES_PASSTHRU;
 303         }
 304 };
 305
 306 MODULE_INIT(ModulePermanentChannels)