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", LOG_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         for (chan_hash::const_iterator i = ServerInstance->chanlist->begin(); i != ServerInstance->chanlist->end(); i++)
  55         {
  56                 Channel* chan = i->second;
  57                 if (!chan->IsModeSet('P'))
  58                         continue;
  59
  60                 char line[1024];
  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                 int lpos = 0, item = 0, ipos = 0;
  73                 while (lpos < 1022 && item < 7)
  74                 {
  75                         char c = items[item][ipos++];
  76                         if (c == 0)
  77                         {
  78                                 // end of this string; hop to next string, insert a quote
  79                                 item++;
  80                                 ipos = 0;
  81                                 c = '"';
  82                         }
  83                         else if (c == '\\' || c == '"')
  84                         {
  85                                 line[lpos++] = '\\';
  86                         }
  87                         line[lpos++] = c;
  88                 }
  89                 line[--lpos] = 0;
  90                 fputs(line, f);
  91         }
  92
  93         int write_error = 0;
  94         write_error = ferror(f);
  95         write_error |= fclose(f);
  96         if (write_error)
  97         {
  98                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot write to new database! %s (%d)", strerror(errno), errno);
  99                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot write to new db: %s (%d)", strerror(errno), errno);
 100                 return false;
 101         }
 102
 103 #ifdef _WIN32
 104         if (remove(permchannelsconf.c_str()))
 105         {
 106                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot remove old database! %s (%d)", strerror(errno), errno);
 107                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot remove old database: %s (%d)", strerror(errno), errno);
 108                 return false;
 109         }
 110 #endif
 111         // Use rename to move temporary to new db - this is guarenteed not to fuck up, even in case of a crash.
 112         if (rename(tempname.c_str(), permchannelsconf.c_str()) < 0)
 113         {
 114                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "permchannels: Cannot move new to old database! %s (%d)", strerror(errno), errno);
 115                 ServerInstance->SNO->WriteToSnoMask('a', "database: cannot replace old with new db: %s (%d)", strerror(errno), errno);
 116                 return false;
 117         }
 118
 119         return true;
 120 }
 121
 122
 123
 124 /** Handles the +P channel mode
 125  */
 126 class PermChannel : public ModeHandler
 127 {
 128  public:
 129         PermChannel(Module* Creator) : ModeHandler(Creator, "permanent", 'P', PARAM_NONE, MODETYPE_CHANNEL) { oper = true; }
 130
 131         ModeAction OnModeChange(User* source, User* dest, Channel* channel, std::string &parameter, bool adding)
 132         {
 133                 if (adding)
 134                 {
 135                         if (!channel->IsModeSet('P'))
 136                         {
 137                                 channel->SetMode('P',true);
 138                                 return MODEACTION_ALLOW;
 139                         }
 140                 }
 141                 else
 142                 {
 143                         if (channel->IsModeSet('P'))
 144                         {
 145                                 channel->SetMode(this,false);
 146                                 if (channel->GetUserCounter() == 0)
 147                                 {
 148                                         channel->DelUser(ServerInstance->FakeClient);
 149                                 }
 150                                 return MODEACTION_ALLOW;
 151                         }
 152                 }
 153
 154                 return MODEACTION_DENY;
 155         }
 156 };
 157
 158 class ModulePermanentChannels : public Module
 159 {
 160         PermChannel p;
 161         bool dirty;
 162 public:
 163
 164         ModulePermanentChannels() : p(this), dirty(false)
 165         {
 166         }
 167
 168         void init() CXX11_OVERRIDE
 169         {
 170                 ServerInstance->Modules->AddService(p);
 171                 Implementation eventlist[] = { I_OnChannelPreDelete, I_OnPostTopicChange, I_OnRawMode, I_OnRehash, I_OnBackgroundTimer };
 172                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 173
 174                 OnRehash(NULL);
 175         }
 176
 177         CullResult cull()
 178         {
 179                 /*
 180                  * DelMode can't remove the +P mode on empty channels, or it will break
 181                  * merging modes with remote servers. Remove the empty channels now as
 182                  * we know this is not the case.
 183                  */
 184                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 185                 while (iter != ServerInstance->chanlist->end())
 186                 {
 187                         Channel* c = iter->second;
 188                         if (c->GetUserCounter() == 0)
 189                         {
 190                                 chan_hash::iterator at = iter;
 191                                 iter++;
 192                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 193                                 ServerInstance->chanlist->erase(at);
 194                                 ServerInstance->GlobalCulls.AddItem(c);
 195                         }
 196                         else
 197                                 iter++;
 198                 }
 199                 ServerInstance->Modes->DelMode(&p);
 200                 return Module::cull();
 201         }
 202
 203         void OnRehash(User *user) CXX11_OVERRIDE
 204         {
 205                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 206         }
 207
 208         void LoadDatabase()
 209         {
 210                 /*
 211                  * Process config-defined list of permanent channels.
 212                  * -- w00t
 213                  */
 214                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 215                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 216                 {
 217                         ConfigTag* tag = i->second;
 218                         std::string channel = tag->getString("channel");
 219                         std::string topic = tag->getString("topic");
 220                         std::string modes = tag->getString("modes");
 221
 222                         if (channel.empty())
 223                         {
 224                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Malformed permchannels tag with empty channel name.");
 225                                 continue;
 226                         }
 227
 228                         Channel *c = ServerInstance->FindChan(channel);
 229
 230                         if (!c)
 231                         {
 232                                 c = new Channel(channel, ServerInstance->Time());
 233                                 if (!topic.empty())
 234                                 {
 235                                         c->SetTopic(NULL, topic, true);
 236
 237                                         /*
 238                                          * Due to the way protocol works in 1.2, we need to hack the topic TS in such a way that this
 239                                          * topic will always win over others.
 240                                          *
 241                                          * This is scheduled for (proper) fixing in a later release, and can be removed at a later date.
 242                                          */
 243                                         c->topicset = 42;
 244                                 }
 245                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Added %s with topic %s", channel.c_str(), topic.c_str());
 246
 247                                 if (modes.empty())
 248                                         continue;
 249
 250                                 irc::spacesepstream list(modes);
 251                                 std::string modeseq;
 252                                 std::string par;
 253
 254                                 list.GetToken(modeseq);
 255
 256                                 // XXX bleh, should we pass this to the mode parser instead? ugly. --w00t
 257                                 for (std::string::iterator n = modeseq.begin(); n != modeseq.end(); ++n)
 258                                 {
 259                                         ModeHandler* mode = ServerInstance->Modes->FindMode(*n, MODETYPE_CHANNEL);
 260                                         if (mode)
 261                                         {
 262                                                 if (mode->GetNumParams(true))
 263                                                         list.GetToken(par);
 264                                                 else
 265                                                         par.clear();
 266
 267                                                 mode->OnModeChange(ServerInstance->FakeClient, ServerInstance->FakeClient, c, par, true);
 268                                         }
 269                                 }
 270                         }
 271                 }
 272         }
 273
 274         ModResult OnRawMode(User* user, Channel* chan, const char mode, const std::string &param, bool adding, int pcnt) CXX11_OVERRIDE
 275         {
 276                 if (chan && (chan->IsModeSet('P') || mode == 'P'))
 277                         dirty = true;
 278
 279                 return MOD_RES_PASSTHRU;
 280         }
 281
 282         void OnPostTopicChange(User*, Channel *c, const std::string&) CXX11_OVERRIDE
 283         {
 284                 if (c->IsModeSet('P'))
 285                         dirty = true;
 286         }
 287
 288         void OnBackgroundTimer(time_t) CXX11_OVERRIDE
 289         {
 290                 if (dirty)
 291                         WriteDatabase();
 292                 dirty = false;
 293         }
 294
 295         void Prioritize()
 296         {
 297                 // XXX: Load the DB here because the order in which modules are init()ed at boot is
 298                 // alphabetical, this means we must wait until all modules have done their init()
 299                 // to be able to set the modes they provide (e.g.: m_stripcolor is inited after us)
 300                 // Prioritize() is called after all module initialization is complete, consequently
 301                 // all modes are available now
 302
 303                 static bool loaded = false;
 304                 if (loaded)
 305                         return;
 306
 307                 loaded = true;
 308
 309                 // Load only when there are no linked servers - we set the TS of the channels we
 310                 // create to the current time, this can lead to desync because spanningtree has
 311                 // no way of knowing what we do
 312                 ProtoServerList serverlist;
 313                 ServerInstance->PI->GetServerList(serverlist);
 314                 if (serverlist.size() < 2)
 315                 {
 316                         try
 317                         {
 318                                 LoadDatabase();
 319                         }
 320                         catch (CoreException& e)
 321                         {
 322                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "Error loading permchannels database: " + std::string(e.GetReason()));
 323                         }
 324                 }
 325         }
 326
 327         Version GetVersion() CXX11_OVERRIDE
 328         {
 329                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 330         }
 331
 332         ModResult OnChannelPreDelete(Channel *c) CXX11_OVERRIDE
 333         {
 334                 if (c->IsModeSet('P'))
 335                         return MOD_RES_DENY;
 336
 337                 return MOD_RES_PASSTHRU;
 338         }
 339 };
 340
 341 MODULE_INIT(ModulePermanentChannels)