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
  23 /* $ModDesc: Provides support for channel mode +P to provide permanent channels */
  24
  25 // Not in a class due to circular dependancy hell.
  26 static std::string permchannelsconf;
  27 static bool WriteDatabase()
  28 {
  29         FILE *f;
  30
  31         if (permchannelsconf.empty())
  32         {
  33                 // Fake success.
  34                 return true;
  35         }
  36
  37         std::string tempname = permchannelsconf + ".tmp";
  38
  39         /*
  40          * We need to perform an atomic write so as not to fuck things up.
  41          * So, let's write to a temporary file, flush and sync the FD, then rename the file..
  42          *              -- w00t
  43          */
  44         f = fopen(tempname.c_str(), "w");
  45         if (!f)
  46         {
  47                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot create database! %s (%d)", strerror(errno), errno);
  48                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot create new db: %s (%d)", strerror(errno), errno);
  49                 return false;
  50         }
  51
  52         fputs("# Permchannels DB\n# This file is autogenerated; any changes will be overwritten!\n<config format=\"compat\">\n", f);
  53         // Now, let's write.
  54         std::string line;
  55         for (chan_hash::const_iterator i = ServerInstance->chanlist->begin(); i != ServerInstance->chanlist->end(); i++)
  56         {
  57                 Channel* chan = i->second;
  58                 if (!chan->IsModeSet('P'))
  59                         continue;
  60
  61                 std::string chants = ConvToStr(chan->age);
  62                 std::string topicts = ConvToStr(chan->topicset);
  63                 const char* items[] =
  64                 {
  65                         "<permchannels channel=",
  66                         chan->name.c_str(),
  67                         " ts=",
  68                         chants.c_str(),
  69                         " topic=",
  70                         chan->topic.c_str(),
  71                         " topicts=",
  72                         topicts.c_str(),
  73                         " topicsetby=",
  74                         chan->setby.c_str(),
  75                         " modes=",
  76                         chan->ChanModes(true),
  77                         ">\n"
  78                 };
  79
  80                 line.clear();
  81                 int item = 0, ipos = 0;
  82                 while (item < 13)
  83                 {
  84                         char c = items[item][ipos++];
  85                         if (c == 0)
  86                         {
  87                                 // end of this string; hop to next string, insert a quote
  88                                 item++;
  89                                 ipos = 0;
  90                                 c = '"';
  91                         }
  92                         else if (c == '\\' || c == '"')
  93                         {
  94                                 line += '\\';
  95                         }
  96                         line += c;
  97                 }
  98
  99                 // Erase last '"'
 100                 line.erase(line.end()-1);
 101                 fputs(line.c_str(), f);
 102         }
 103
 104         int write_error = 0;
 105         write_error = ferror(f);
 106         write_error |= fclose(f);
 107         if (write_error)
 108         {
 109                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot write to new database! %s (%d)", strerror(errno), errno);
 110                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot write to new db: %s (%d)", strerror(errno), errno);
 111                 return false;
 112         }
 113
 114 #ifdef _WIN32
 115         if (remove(permchannelsconf.c_str()))
 116         {
 117                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot remove old database! %s (%d)", strerror(errno), errno);
 118                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot remove old database: %s (%d)", strerror(errno), errno);
 119                 return false;
 120         }
 121 #endif
 122         // Use rename to move temporary to new db - this is guarenteed not to fuck up, even in case of a crash.
 123         if (rename(tempname.c_str(), permchannelsconf.c_str()) < 0)
 124         {
 125                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot move new to old database! %s (%d)", strerror(errno), errno);
 126                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot replace old with new db: %s (%d)", strerror(errno), errno);
 127                 return false;
 128         }
 129
 130         return true;
 131 }
 132
 133
 134
 135 /** Handles the +P channel mode
 136  */
 137 class PermChannel : public ModeHandler
 138 {
 139  public:
 140         PermChannel(Module* Creator) : ModeHandler(Creator, "permanent", 'P', PARAM_NONE, MODETYPE_CHANNEL) { oper = true; }
 141
 142         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 143         {
 144                 if (adding)
 145                 {
 146                         if (!channel->IsModeSet('P'))
 147                         {
 148                                 channel->SetMode('P',true);
 149                                 return MODEACTION_ALLOW;
 150                         }
 151                 }
 152                 else
 153                 {
 154                         if (channel->IsModeSet('P'))
 155                         {
 156                                 channel->SetMode(this,false);
 157                                 if (channel->GetUserCounter() == 0)
 158                                 {
 159                                         channel->DelUser(ServerInstance->FakeClient);
 160                                 }
 161                                 return MODEACTION_ALLOW;
 162                         }
 163                 }
 164
 165                 return MODEACTION_DENY;
 166         }
 167 };
 168
 169 class ModulePermanentChannels : public Module
 170 {
 171         PermChannel p;
 172         bool dirty;
 173 public:
 174
 175         ModulePermanentChannels() : p(this), dirty(false)
 176         {
 177         }
 178
 179         void init()
 180         {
 181                 ServerInstance->Modules->AddService(p);
 182                 Implementation eventlist[] = { I_OnChannelPreDelete, I_OnPostTopicChange, I_OnRawMode, I_OnRehash, I_OnBackgroundTimer };
 183                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 184
 185                 OnRehash(NULL);
 186         }
 187
 188         CullResult cull()
 189         {
 190                 /*
 191                  * DelMode can't remove the +P mode on empty channels, or it will break
 192                  * merging modes with remote servers. Remove the empty channels now as
 193                  * we know this is not the case.
 194                  */
 195                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 196                 while (iter != ServerInstance->chanlist->end())
 197                 {
 198                         Channel* c = iter->second;
 199                         if (c->GetUserCounter() == 0)
 200                         {
 201                                 chan_hash::iterator at = iter;
 202                                 iter++;
 203                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 204                                 ServerInstance->chanlist->erase(at);
 205                                 ServerInstance->GlobalCulls.AddItem(c);
 206                         }
 207                         else
 208                                 iter++;
 209                 }
 210                 ServerInstance->Modes->DelMode(&p);
 211                 return Module::cull();
 212         }
 213
 214         virtual void OnRehash(User *user)
 215         {
 216                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 217         }
 218
 219         void LoadDatabase()
 220         {
 221                 /*
 222                  * Process config-defined list of permanent channels.
 223                  * -- w00t
 224                  */
 225                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 226                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 227                 {
 228                         ConfigTag* tag = i->second;
 229                         std::string channel = tag->getString("channel");
 230                         std::string topic = tag->getString("topic");
 231                         std::string modes = tag->getString("modes");
 232
 233                         if ((channel.empty()) || (channel.length() > ServerInstance->Config->Limits.ChanMax))
 234                         {
 235                                 ServerInstance->Logs->Log("m_permchannels", DEFAULT, "Ignoring permchannels tag with empty or too long channel name (\"" + channel + "\")");
 236                                 continue;
 237                         }
 238
 239                         Channel *c = ServerInstance->FindChan(channel);
 240
 241                         if (!c)
 242                         {
 243                                 time_t TS = tag->getInt("ts");
 244                                 c = new Channel(channel, ((TS > 0) ? TS : ServerInstance->Time()));
 245
 246                                 c->SetTopic(NULL, topic, true);
 247                                 c->setby = tag->getString("topicsetby");
 248                                 unsigned int topicset = tag->getInt("topicts");
 249                                 // SetTopic() sets the topic TS to now, if there was no topicts saved then don't overwrite that with a 0
 250                                 if (topicset > 0)
 251                                         c->topicset = topicset;
 252
 253                                 ServerInstance->Logs->Log("m_permchannels", DEBUG, "Added %s with topic %s", channel.c_str(), topic.c_str());
 254
 255                                 if (modes.empty())
 256                                         continue;
 257
 258                                 irc::spacesepstream list(modes);
 259                                 std::string modeseq;
 260                                 std::string par;
 261
 262                                 list.GetToken(modeseq);
 263
 264                                 // XXX bleh, should we pass this to the mode parser instead? ugly. --w00t
 265                                 for (std::string::iterator n = modeseq.begin(); n != modeseq.end(); ++n)
 266                                 {
 267                                         ModeHandler* mode = ServerInstance->Modes->FindMode(*n, MODETYPE_CHANNEL);
 268                                         if (mode)
 269                                         {
 270                                                 if (mode->GetNumParams(true))
 271                                                         list.GetToken(par);
 272                                                 else
 273                                                         par.clear();
 274
 275                                                 mode->OnModeChange(ServerInstance->FakeClient, ServerInstance->FakeClient, c, par, true);
 276                                         }
 277                                 }
 278                         }
 279                 }
 280         }
 281
 282         virtual ModResult OnRawMode(User* user, Channel* chan, const char mode, const std::string &param, bool adding, int pcnt)
 283         {
 284                 if (chan && (chan->IsModeSet('P') || mode == 'P'))
 285                         dirty = true;
 286
 287                 return MOD_RES_PASSTHRU;
 288         }
 289
 290         virtual void OnPostTopicChange(User*, Channel *c, const std::string&)
 291         {
 292                 if (c->IsModeSet('P'))
 293                         dirty = true;
 294         }
 295
 296         void OnBackgroundTimer(time_t)
 297         {
 298                 if (dirty)
 299                         WriteDatabase();
 300                 dirty = false;
 301         }
 302
 303         void Prioritize()
 304         {
 305                 // XXX: Load the DB here because the order in which modules are init()ed at boot is
 306                 // alphabetical, this means we must wait until all modules have done their init()
 307                 // to be able to set the modes they provide (e.g.: m_stripcolor is inited after us)
 308                 // Prioritize() is called after all module initialization is complete, consequently
 309                 // all modes are available now
 310
 311                 static bool loaded = false;
 312                 if (loaded)
 313                         return;
 314
 315                 loaded = true;
 316
 317                 // Load only when there are no linked servers - we set the TS of the channels we
 318                 // create to the current time, this can lead to desync because spanningtree has
 319                 // no way of knowing what we do
 320                 ProtoServerList serverlist;
 321                 ServerInstance->PI->GetServerList(serverlist);
 322                 if (serverlist.size() < 2)
 323                 {
 324                         try
 325                         {
 326                                 LoadDatabase();
 327                         }
 328                         catch (CoreException& e)
 329                         {
 330                                 ServerInstance->Logs->Log("m_permchannels", DEFAULT, "Error loading permchannels database: " + std::string(e.GetReason()));
 331                         }
 332                 }
 333         }
 334
 335         virtual Version GetVersion()
 336         {
 337                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 338         }
 339
 340         virtual ModResult OnChannelPreDelete(Channel *c)
 341         {
 342                 if (c->IsModeSet('P'))
 343                         return MOD_RES_DENY;
 344
 345                 return MOD_RES_PASSTHRU;
 346         }
 347 };
 348
 349 MODULE_INIT(ModulePermanentChannels)