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                                 channel->CheckDestroy();
 147                                 return MODEACTION_ALLOW;
 148                         }
 149                 }
 150
 151                 return MODEACTION_DENY;
 152         }
 153 };
 154
 155 class ModulePermanentChannels : public Module
 156 {
 157         PermChannel p;
 158         bool dirty;
 159 public:
 160
 161         ModulePermanentChannels() : p(this), dirty(false)
 162         {
 163         }
 164
 165         void init() CXX11_OVERRIDE
 166         {
 167                 ServerInstance->Modules->AddService(p);
 168                 Implementation eventlist[] = { I_OnChannelPreDelete, I_OnPostTopicChange, I_OnRawMode, I_OnRehash, I_OnBackgroundTimer };
 169                 ServerInstance->Modules->Attach(eventlist, this, sizeof(eventlist)/sizeof(Implementation));
 170
 171                 OnRehash(NULL);
 172         }
 173
 174         CullResult cull()
 175         {
 176                 /*
 177                  * DelMode can't remove the +P mode on empty channels, or it will break
 178                  * merging modes with remote servers. Remove the empty channels now as
 179                  * we know this is not the case.
 180                  */
 181                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 182                 while (iter != ServerInstance->chanlist->end())
 183                 {
 184                         Channel* c = iter->second;
 185                         if (c->GetUserCounter() == 0)
 186                         {
 187                                 chan_hash::iterator at = iter;
 188                                 iter++;
 189                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 190                                 ServerInstance->chanlist->erase(at);
 191                                 ServerInstance->GlobalCulls.AddItem(c);
 192                         }
 193                         else
 194                                 iter++;
 195                 }
 196                 ServerInstance->Modes->DelMode(&p);
 197                 return Module::cull();
 198         }
 199
 200         void OnRehash(User *user) CXX11_OVERRIDE
 201         {
 202                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 203         }
 204
 205         void LoadDatabase()
 206         {
 207                 /*
 208                  * Process config-defined list of permanent channels.
 209                  * -- w00t
 210                  */
 211                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 212                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 213                 {
 214                         ConfigTag* tag = i->second;
 215                         std::string channel = tag->getString("channel");
 216                         std::string topic = tag->getString("topic");
 217                         std::string modes = tag->getString("modes");
 218
 219                         if (channel.empty())
 220                         {
 221                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Malformed permchannels tag with empty channel name.");
 222                                 continue;
 223                         }
 224
 225                         Channel *c = ServerInstance->FindChan(channel);
 226
 227                         if (!c)
 228                         {
 229                                 c = new Channel(channel, ServerInstance->Time());
 230                                 if (!topic.empty())
 231                                 {
 232                                         c->SetTopic(ServerInstance->FakeClient, topic, true);
 233
 234                                         /*
 235                                          * Due to the way protocol works in 1.2, we need to hack the topic TS in such a way that this
 236                                          * topic will always win over others.
 237                                          *
 238                                          * This is scheduled for (proper) fixing in a later release, and can be removed at a later date.
 239                                          */
 240                                         c->topicset = 42;
 241                                 }
 242                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEBUG, "Added %s with topic %s", channel.c_str(), topic.c_str());
 243
 244                                 if (modes.empty())
 245                                         continue;
 246
 247                                 irc::spacesepstream list(modes);
 248                                 std::string modeseq;
 249                                 std::string par;
 250
 251                                 list.GetToken(modeseq);
 252
 253                                 // XXX bleh, should we pass this to the mode parser instead? ugly. --w00t
 254                                 for (std::string::iterator n = modeseq.begin(); n != modeseq.end(); ++n)
 255                                 {
 256                                         ModeHandler* mode = ServerInstance->Modes->FindMode(*n, MODETYPE_CHANNEL);
 257                                         if (mode)
 258                                         {
 259                                                 if (mode->GetNumParams(true))
 260                                                         list.GetToken(par);
 261                                                 else
 262                                                         par.clear();
 263
 264                                                 mode->OnModeChange(ServerInstance->FakeClient, ServerInstance->FakeClient, c, par, true);
 265                                         }
 266                                 }
 267                         }
 268                 }
 269         }
 270
 271         ModResult OnRawMode(User* user, Channel* chan, const char mode, const std::string &param, bool adding, int pcnt) CXX11_OVERRIDE
 272         {
 273                 if (chan && (chan->IsModeSet('P') || mode == 'P'))
 274                         dirty = true;
 275
 276                 return MOD_RES_PASSTHRU;
 277         }
 278
 279         void OnPostTopicChange(User*, Channel *c, const std::string&) CXX11_OVERRIDE
 280         {
 281                 if (c->IsModeSet('P'))
 282                         dirty = true;
 283         }
 284
 285         void OnBackgroundTimer(time_t) CXX11_OVERRIDE
 286         {
 287                 if (dirty)
 288                         WriteDatabase();
 289                 dirty = false;
 290         }
 291
 292         void Prioritize()
 293         {
 294                 // XXX: Load the DB here because the order in which modules are init()ed at boot is
 295                 // alphabetical, this means we must wait until all modules have done their init()
 296                 // to be able to set the modes they provide (e.g.: m_stripcolor is inited after us)
 297                 // Prioritize() is called after all module initialization is complete, consequently
 298                 // all modes are available now
 299
 300                 static bool loaded = false;
 301                 if (loaded)
 302                         return;
 303
 304                 loaded = true;
 305
 306                 // Load only when there are no linked servers - we set the TS of the channels we
 307                 // create to the current time, this can lead to desync because spanningtree has
 308                 // no way of knowing what we do
 309                 ProtoServerList serverlist;
 310                 ServerInstance->PI->GetServerList(serverlist);
 311                 if (serverlist.size() < 2)
 312                 {
 313                         try
 314                         {
 315                                 LoadDatabase();
 316                         }
 317                         catch (CoreException& e)
 318                         {
 319                                 ServerInstance->Logs->Log("m_permchannels", LOG_DEFAULT, "Error loading permchannels database: " + std::string(e.GetReason()));
 320                         }
 321                 }
 322         }
 323
 324         Version GetVersion() CXX11_OVERRIDE
 325         {
 326                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 327         }
 328
 329         ModResult OnChannelPreDelete(Channel *c) CXX11_OVERRIDE
 330         {
 331                 if (c->IsModeSet('P'))
 332                         return MOD_RES_DENY;
 333
 334                 return MOD_RES_PASSTHRU;
 335         }
 336 };
 337
 338 MODULE_INIT(ModulePermanentChannels)