src/modules/m_xline_db.cpp

   1 /*       +------------------------------------+
   2  *       | Inspire Internet Relay Chat Daemon |
   3  *       +------------------------------------+
   4  *
   5  *  InspIRCd: (C) 2002-2007 InspIRCd Development Team
   6  * See: http://www.inspircd.org/wiki/index.php/Credits
   7  *
   8  * This program is free but copyrighted software; see
   9  *            the file COPYING for details.
  10  *
  11  * ---------------------------------------------------
  12  */
  13
  14 #include "inspircd.h"
  15 #include "xline.h"
  16
  17 /* $ModDesc: Keeps a dynamic log of all XLines created, and stores them in a seperate conf file (xline.db). */
  18
  19 class ModuleXLineDB : public Module
  20 {
  21         std::vector<XLine *> xlines;
  22         bool reading_db;                        // If this is true, addlines are as a result of db reading, so don't bother flushing the db to disk.
  23                                                 // DO REMEMBER TO SET IT, otherwise it's annoying :P
  24  public:
  25         ModuleXLineDB(InspIRCd* Me) : Module(Me)
  26         {
  27                 Implementation eventlist[] = { I_OnAddLine, I_OnDelLine };
  28                 ServerInstance->Modules->Attach(eventlist, this, 2);
  29
  30                 reading_db = true;
  31                 ReadDatabase();
  32                 reading_db = false;
  33         }
  34
  35         virtual ~ModuleXLineDB()
  36         {
  37         }
  38
  39         /** Called whenever an xline is added by a local user.
  40          * This method is triggered after the line is added.
  41          * @param source The sender of the line or NULL for local server
  42          * @param line The xline being added
  43          */
  44         void OnAddLine(User* source, XLine* line)
  45         {
  46                 ServerInstance->Log(DEBUG, "xlinedb: Adding a line");
  47                 xlines.push_back(line);
  48
  49                 if (!reading_db)
  50                 {
  51                         WriteDatabase();
  52                 }
  53         }
  54
  55         /** Called whenever an xline is deleted.
  56          * This method is triggered after the line is deleted.
  57          * @param source The user removing the line or NULL for local server
  58          * @param line the line being deleted
  59          */
  60         void OnDelLine(User* source, XLine* line)
  61         {
  62                 ServerInstance->Log(DEBUG, "xlinedb: Removing a line");
  63                 for (std::vector<XLine *>::iterator i = xlines.begin(); i != xlines.end(); i++)
  64                 {
  65                         if ((*i) == line)
  66                         {
  67                                 xlines.erase(i);
  68                                 break;
  69                         }
  70                 }
  71
  72                 WriteDatabase();
  73         }
  74
  75         bool WriteDatabase()
  76         {
  77                 FILE *f;
  78
  79                 /*
  80                  * We need to perform an atomic write so as not to fuck things up.
  81                  * So, let's write to a temporary file, flush and sync the FD, then rename the file..
  82                  * Technically, that means that this can block, but I have *never* seen that.
  83                  *              -- w00t
  84                  */
  85                 ServerInstance->Log(DEBUG, "xlinedb: Opening temporary database");
  86                 f = fopen("xline.db.new", "w");
  87                 if (!f)
  88                 {
  89                         ServerInstance->Log(DEBUG, "xlinedb: Cannot create database! %s (%d)", strerror(errno), errno);
  90                         ServerInstance->SNO->WriteToSnoMask('x', "database: cannot create new db: %s (%d)", strerror(errno), errno);
  91                         return false;
  92                 }
  93
  94                 ServerInstance->Log(DEBUG, "xlinedb: Opened. Writing..");
  95
  96                 /*
  97                  * Now, much as I hate writing semi-unportable formats, additional
  98                  * xline types may not have a conf tag, so let's just write them.
  99                  * In addition, let's use a file version, so we can maintain some
 100                  * semblance of backwards compatibility for reading on startup..
 101                  *              -- w00t
 102                  */
 103                 fprintf(f, "VERSION 1\n");
 104
 105                 // Now, let's write.
 106                 XLine *line;
 107                 for (std::vector<XLine *>::iterator i = xlines.begin(); i != xlines.end(); i++)
 108                 {
 109                         line = (*i);
 110                         fprintf(f, "LINE %s %s %s %lu %lu :%s\n", line->type.c_str(), line->Displayable(),
 111                                 ServerInstance->Config->ServerName, line->set_time, line->duration, line->reason);
 112                 }
 113
 114                 ServerInstance->Log(DEBUG, "xlinedb: Finished writing XLines. Checking for error..");
 115
 116                 int write_error = 0;
 117                 write_error = ferror(f);
 118                 write_error |= fclose(f);
 119                 if (write_error)
 120                 {
 121                         ServerInstance->Log(DEBUG, "xlinedb: Cannot write to new database! %s (%d)", strerror(errno), errno);
 122                         ServerInstance->SNO->WriteToSnoMask('x', "database: cannot write to new db: %s (%d)", strerror(errno), errno);
 123                         return false;
 124                 }
 125
 126                 // Use rename to move temporary to new db - this is guarenteed not to fuck up, even in case of a crash.
 127                 if (rename("xline.db.new", "xline.db") < 0)
 128                 {
 129                         ServerInstance->Log(DEBUG, "xlinedb: Cannot move new to old database! %s (%d)", strerror(errno), errno);
 130                         ServerInstance->SNO->WriteToSnoMask('x', "database: cannot replace old with new db: %s (%d)", strerror(errno), errno);
 131                         return false;
 132                 }
 133
 134                 return true;
 135         }
 136
 137         bool ReadDatabase()
 138         {
 139                 FILE *f;
 140                 char linebuf[MAXBUF];
 141                 unsigned int lineno = 0;
 142
 143                 f = fopen("xline.db", "r");
 144                 if (!f)
 145                 {
 146                         if (errno == ENOENT)
 147                         {
 148                                 /* xline.db doesn't exist, fake good return value (we don't care about this) */
 149                                 return true;
 150                         }
 151                         else
 152                         {
 153                                 /* this might be slightly more problematic. */
 154                                 ServerInstance->Log(DEBUG, "xlinedb: Cannot read database! %s (%d)", strerror(errno), errno);
 155                                 ServerInstance->SNO->WriteToSnoMask('x', "database: cannot read db: %s (%d)", strerror(errno), errno);
 156                                 return false;
 157                         }
 158                 }
 159
 160                 while (fgets(linebuf, MAXBUF, f))
 161                 {
 162                         char *c = linebuf;
 163
 164                         while (c && *c)
 165                         {
 166                                 if (*c == '\n')
 167                                 {
 168                                         *c = '\0';
 169                                 }
 170
 171                                 c++;
 172                         }
 173                         // Smart man might think of initing to 1, and moving this to the bottom. Don't. We use continue in this loop.
 174                         lineno++;
 175
 176                         // Inspired by the command parser. :)
 177                         irc::tokenstream tokens(linebuf);
 178                         int items = 0;
 179                         std::string command_p[MAXPARAMETERS];
 180                         std::string tmp;
 181
 182                         while (tokens.GetToken(tmp) && (items < MAXPARAMETERS))
 183                         {
 184                                 command_p[items] = tmp.c_str();
 185                                 items++;
 186                         }
 187
 188                         ServerInstance->Log(DEBUG, "xlinedb: Processing %s", linebuf);
 189
 190                         if (command_p[0] == "VERSION")
 191                         {
 192                                 if (command_p[1] == "1")
 193                                 {
 194                                         ServerInstance->Log(DEBUG, "xlinedb: Reading db version %s", command_p[1].c_str());
 195                                 }
 196                                 else
 197                                 {
 198                                         fclose(f);
 199                                         ServerInstance->Log(DEBUG, "xlinedb: I got database version %s - I don't understand it", command_p[1].c_str());
 200                                         ServerInstance->SNO->WriteToSnoMask('x', "database: I got a database version (%s) I don't understand", command_p[1].c_str());
 201                                         return false;
 202                                 }
 203                         }
 204                         else if (command_p[0] == "LINE")
 205                         {
 206                                 // Mercilessly stolen from spanningtree
 207                                 XLineFactory* xlf = ServerInstance->XLines->GetFactory(command_p[1]);
 208
 209                                 if (!xlf)
 210                                 {
 211                                         ServerInstance->SNO->WriteToSnoMask('x', "database: Unknown line type (%s).", command_p[1].c_str());
 212                                         continue;
 213                                 }
 214
 215                                 XLine* xl = xlf->Generate(ServerInstance->Time(), atoi(command_p[5].c_str()), command_p[3].c_str(), command_p[6].c_str(), command_p[2].c_str());
 216                                 xl->SetCreateTime(atoi(command_p[4].c_str()));
 217
 218                                 if (ServerInstance->XLines->AddLine(xl, NULL))
 219                                 {
 220                                         ServerInstance->SNO->WriteToSnoMask('x', "database: Added a line of type %s", command_p[1].c_str());
 221                                 }
 222                         }
 223                 }
 224
 225                 return true;
 226         }
 227
 228
 229
 230         virtual Version GetVersion()
 231         {
 232                 return Version(1, 1, 0, 0, VF_VENDOR, API_VERSION);
 233         }
 234 };
 235
 236 MODULE_INIT(ModuleXLineDB)
 237