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         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",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",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",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()
 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                 // Load only when there are no linked servers - we set the TS of the channels we
 177                 // create to the current time, this can lead to desync because spanningtree has
 178                 // no way of knowing what we do
 179                 ProtoServerList serverlist;
 180                 ServerInstance->PI->GetServerList(serverlist);
 181                 if (serverlist.size() < 2)
 182                         LoadDatabase();
 183         }
 184
 185         CullResult cull()
 186         {
 187                 /*
 188                  * DelMode can't remove the +P mode on empty channels, or it will break
 189                  * merging modes with remote servers. Remove the empty channels now as
 190                  * we know this is not the case.
 191                  */
 192                 chan_hash::iterator iter = ServerInstance->chanlist->begin();
 193                 while (iter != ServerInstance->chanlist->end())
 194                 {
 195                         Channel* c = iter->second;
 196                         if (c->GetUserCounter() == 0)
 197                         {
 198                                 chan_hash::iterator at = iter;
 199                                 iter++;
 200                                 FOREACH_MOD(I_OnChannelDelete, OnChannelDelete(c));
 201                                 ServerInstance->chanlist->erase(at);
 202                                 ServerInstance->GlobalCulls.AddItem(c);
 203                         }
 204                         else
 205                                 iter++;
 206                 }
 207                 ServerInstance->Modes->DelMode(&p);
 208                 return Module::cull();
 209         }
 210
 211         virtual void OnRehash(User *user)
 212         {
 213                 permchannelsconf = ServerInstance->Config->ConfValue("permchanneldb")->getString("filename");
 214         }
 215
 216         void LoadDatabase()
 217         {
 218                 /*
 219                  * Process config-defined list of permanent channels.
 220                  * -- w00t
 221                  */
 222                 ConfigTagList permchannels = ServerInstance->Config->ConfTags("permchannels");
 223                 for (ConfigIter i = permchannels.first; i != permchannels.second; ++i)
 224                 {
 225                         ConfigTag* tag = i->second;
 226                         std::string channel = tag->getString("channel");
 227                         std::string topic = tag->getString("topic");
 228                         std::string modes = tag->getString("modes");
 229
 230                         if (channel.empty())
 231                         {
 232                                 ServerInstance->Logs->Log("m_permchannels", DEBUG, "Malformed permchannels tag with empty channel name.");
 233                                 continue;
 234                         }
 235
 236                         Channel *c = ServerInstance->FindChan(channel);
 237
 238                         if (!c)
 239                         {
 240                                 c = new Channel(channel, ServerInstance->Time());
 241                                 if (!topic.empty())
 242                                 {
 243                                         c->SetTopic(NULL, topic, true);
 244
 245                                         /*
 246                                          * Due to the way protocol works in 1.2, we need to hack the topic TS in such a way that this
 247                                          * topic will always win over others.
 248                                          *
 249                                          * This is scheduled for (proper) fixing in a later release, and can be removed at a later date.
 250                                          */
 251                                         c->topicset = 42;
 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         virtual Version GetVersion()
 304         {
 305                 return Version("Provides support for channel mode +P to provide permanent channels",VF_VENDOR);
 306         }
 307
 308         virtual ModResult OnChannelPreDelete(Channel *c)
 309         {
 310                 if (c->IsModeSet('P'))
 311                         return MOD_RES_DENY;
 312
 313                 return MOD_RES_PASSTHRU;
 314         }
 315 };
 316
 317 MODULE_INIT(ModulePermanentChannels)