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                 const char* items[] =
  62                 {
  63                         "<permchannels channel=",
  64                         chan->name.c_str(),
  65                         " topic=",
  66                         chan->topic.c_str(),
  67                         " modes=",
  68                         chan->ChanModes(true),
  69                         ">\n"
  70                 };
  71
  72                 line.clear();
  73                 int item = 0, ipos = 0;
  74                 while (item < 7)
  75                 {
  76                         char c = items[item][ipos++];
  77                         if (c == 0)
  78                         {
  79                                 // end of this string; hop to next string, insert a quote
  80                                 item++;
  81                                 ipos = 0;
  82                                 c = '"';
  83                         }
  84                         else if (c == '\\' || c == '"')
  85                         {
  86                                 line += '\\';
  87                         }
  88                         line += c;
  89                 }
  90
  91                 // Erase last '"'
  92                 line.erase(line.end()-1);
  93                 fputs(line.c_str(), f);
  94         }
  95
  96         int write_error = 0;
  97         write_error = ferror(f);
  98         write_error |= fclose(f);
  99         if (write_error)
 100         {
 101                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot write to new database! %s (%d)", strerror(errno), errno);
 102                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot write to new db: %s (%d)", strerror(errno), errno);
 103                 return false;
 104         }
 105
 106 #ifdef _WIN32
 107         if (remove(permchannelsconf.c_str()))
 108         {
 109                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot remove old database! %s (%d)", strerror(errno), errno);
 110                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot remove old database: %s (%d)", strerror(errno), errno);
 111                 return false;
 112         }
 113 #endif
 114         // Use rename to move temporary to new db - this is guarenteed not to fuck up, even in case of a crash.
 115         if (rename(tempname.c_str(), permchannelsconf.c_str()) < 0)
 116         {
 117                 ServerInstance->Logs->Log("m_permchannels",DEFAULT, "permchannels: Cannot move new to old database! %s (%d)", strerror(errno), errno);
 118                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot replace old with new db: %s (%d)", strerror(errno), errno);
 119                 return false;
 120         }
 121
 122         return true;
 123 }
 124
 125
 126
 127 /** Handles the +P channel mode
 128  */
 129 class PermChannel : public ModeHandler
 130 {
 131  public:
 132         PermChannel(Module* Creator) : ModeHandler(Creator, "permanent", 'P', PARAM_NONE, MODETYPE_CHANNEL) { oper = true; }
 133
 134         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 135         {
 136                 if (adding)
 137                 {
 138                         if (!channel->IsModeSet('P'))
 139                         {
 140                                 channel->SetMode('P',true);
 141                                 return MODEACTION_ALLOW;
 142                         }
 143                 }
 144                 else
 145                 {
 146                         if (channel->IsModeSet('P'))
 147                         {
 148                                 channel->SetMode(this,false);
 149                                 if (channel->GetUserCounter() == 0)
 150                                 {
 151                                         channel->DelUser(ServerInstance->FakeClient);
 152                                 }
 153                                 return MODEACTION_ALLOW;
 154                         }
 155                 }
 156
 157                 return MODEACTION_DENY;
 158         }
 159 };
 160
 161 class ModulePermanentChannels : public Module
 162 {
 163         PermChannel p;
 164         bool dirty;
 165 public:
 166
 167         ModulePermanentChannels() : p(this), dirty(false)
 168         {
 169         }
 170
 171         void init()
 172         {
 173                 ServerInstance->Modules->AddService(p);
 174                 Implementation eventlist[] = { I_OnChannelPreDelete, I_OnPostTopicChange, I_OnRawMode, I_OnRehash, I_OnBackgroundTimer };
 175                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 176
 177                 OnRehash(NULL);
 178         }
 179
 180         CullResult cull()
 181         {
 182                 /*
 183                  * DelMode can't remove the +P mode on empty channels, or it will break
 184                  * merging modes with remote servers. Remove the empty channels now as
 185                  * we know this is not the case.
 186                  */
 187                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 188                 while (iter != ServerInstance->chanlist->end())
 189                 {
 190                         Channel* c = iter->second;
 191                         if (c->GetUserCounter() == 0)
 192                         {
 193                                 chan_hash::iterator at = iter;
 194                                 iter++;
 195                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 196                                 ServerInstance->chanlist->erase(at);
 197                                 ServerInstance->GlobalCulls.AddItem(c);
 198                         }
 199                         else
 200                                 iter++;
 201                 }
 202                 ServerInstance->Modes->DelMode(&p);
 203                 return Module::cull();
 204         }
 205
 206         virtual void OnRehash(User *user)
 207         {
 208                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 209         }
 210
 211         void LoadDatabase()
 212         {
 213                 /*
 214                  * Process config-defined list of permanent channels.
 215                  * -- w00t
 216                  */
 217                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 218                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 219                 {
 220                         ConfigTag* tag = i->second;
 221                         std::string channel = tag->getString("channel");
 222                         std::string topic = tag->getString("topic");
 223                         std::string modes = tag->getString("modes");
 224
 225                         if (channel.empty())
 226                         {
 227                                 ServerInstance->Logs->Log("m_permchannels", DEBUG, "Malformed permchannels tag with empty channel name.");
 228                                 continue;
 229                         }
 230
 231                         Channel *c = ServerInstance->FindChan(channel);
 232
 233                         if (!c)
 234                         {
 235                                 c = new Channel(channel, ServerInstance->Time());
 236                                 if (!topic.empty())
 237                                 {
 238                                         c->SetTopic(NULL, topic, true);
 239
 240                                         /*
 241                                          * Due to the way protocol works in 1.2, we need to hack the topic TS in such a way that this
 242                                          * topic will always win over others.
 243                                          *
 244                                          * This is scheduled for (proper) fixing in a later release, and can be removed at a later date.
 245                                          */
 246                                         c->topicset = 42;
 247                                 }
 248                                 ServerInstance->Logs->Log("m_permchannels", DEBUG, "Added %s with topic %s", channel.c_str(), topic.c_str());
 249
 250                                 if (modes.empty())
 251                                         continue;
 252
 253                                 irc::spacesepstream list(modes);
 254                                 std::string modeseq;
 255                                 std::string par;
 256
 257                                 list.GetToken(modeseq);
 258
 259                                 // XXX bleh, should we pass this to the mode parser instead? ugly. --w00t
 260                                 for (std::string::iterator n = modeseq.begin(); n != modeseq.end(); ++n)
 261                                 {
 262                                         ModeHandler* mode = ServerInstance->Modes->FindMode(*n, MODETYPE_CHANNEL);
 263                                         if (mode)
 264                                         {
 265                                                 if (mode->GetNumParams(true))
 266                                                         list.GetToken(par);
 267                                                 else
 268                                                         par.clear();
 269
 270                                                 mode->OnModeChange(ServerInstance->FakeClient, ServerInstance->FakeClient, c, par, true);
 271                                         }
 272                                 }
 273                         }
 274                 }
 275         }
 276
 277         virtual ModResult OnRawMode(User* user, Channel* chan, const char mode, const std::string &param, bool adding, int pcnt)
 278         {
 279                 if (chan && (chan->IsModeSet('P') || mode == 'P'))
 280                         dirty = true;
 281
 282                 return MOD_RES_PASSTHRU;
 283         }
 284
 285         virtual void OnPostTopicChange(User*, Channel *c, const std::string&)
 286         {
 287                 if (c->IsModeSet('P'))
 288                         dirty = true;
 289         }
 290
 291         void OnBackgroundTimer(time_t)
 292         {
 293                 if (dirty)
 294                         WriteDatabase();
 295                 dirty = false;
 296         }
 297
 298         void Prioritize()
 299         {
 300                 // XXX: Load the DB here because the order in which modules are init()ed at boot is
 301                 // alphabetical, this means we must wait until all modules have done their init()
 302                 // to be able to set the modes they provide (e.g.: m_stripcolor is inited after us)
 303                 // Prioritize() is called after all module initialization is complete, consequently
 304                 // all modes are available now
 305
 306                 static bool loaded = false;
 307                 if (loaded)
 308                         return;
 309
 310                 loaded = true;
 311
 312                 // Load only when there are no linked servers - we set the TS of the channels we
 313                 // create to the current time, this can lead to desync because spanningtree has
 314                 // no way of knowing what we do
 315                 ProtoServerList serverlist;
 316                 ServerInstance->PI->GetServerList(serverlist);
 317                 if (serverlist.size() < 2)
 318                 {
 319                         try
 320                         {
 321                                 LoadDatabase();
 322                         }
 323                         catch (CoreException& e)
 324                         {
 325                                 ServerInstance->Logs->Log("m_permchannels", DEFAULT, "Error loading permchannels database: " + std::string(e.GetReason()));
 326                         }
 327                 }
 328         }
 329
 330         virtual Version GetVersion()
 331         {
 332                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 333         }
 334
 335         virtual ModResult OnChannelPreDelete(Channel *c)
 336         {
 337                 if (c->IsModeSet('P'))
 338                         return MOD_RES_DENY;
 339
 340                 return MOD_RES_PASSTHRU;
 341         }
 342 };
 343
 344 MODULE_INIT(ModulePermanentChannels)