channel/channelindex.c

   1 /* channelindex.c */
   2
   3 #include "channel.h"
   4 #include "../irc/irc_config.h"
   5 #include "../lib/irc_string.h"
   6 #include <stdio.h>
   7 #include <string.h>
   8
   9 #define channelhash(x)  (crc32i(x)%CHANNELHASHSIZE)
  10
  11 chanindex *chantable[CHANNELHASHSIZE];
  12 sstring *extnames[MAXCHANNELEXTS];
  13
  14 unsigned int channelmarker;
  15
  16 void initchannelindex() {
  17   memset(chantable,0,sizeof(chantable));
  18   memset(extnames,0,sizeof(extnames));
  19   channelmarker=0;
  20 }
  21
  22 chanindex *findchanindex(const char *name) {
  23   chanindex *cip;
  24   int hash=channelhash(name);
  25
  26   for (cip=chantable[hash];cip;cip=cip->next) {
  27     if (!ircd_strcmp(cip->name->content,name)) {
  28       return cip;
  29     }
  30   }
  31
  32   return NULL;
  33 }
  34
  35 chanindex *findorcreatechanindex(const char *name) {
  36   chanindex *cip;
  37   int hash=channelhash(name);
  38   int i;
  39
  40   for (cip=chantable[hash];cip;cip=cip->next) {
  41     if (!ircd_strcmp(cip->name->content,name)) {
  42       return cip;
  43     }
  44   }
  45
  46   cip=getchanindex();
  47
  48   cip->name=getsstring(name,CHANNELLEN);
  49   cip->channel=NULL;
  50   cip->marker=0;
  51   cip->next=chantable[hash];
  52   chantable[hash]=cip;
  53
  54   for(i=0;i<MAXCHANNELEXTS;i++) {
  55     cip->exts[i]=NULL;
  56   }
  57
  58   return cip;
  59 }
  60
  61 void releasechanindex(chanindex *cip) {
  62   int i;
  63   chanindex **cih;
  64   int hash;
  65
  66   /* If any module is still using the channel, do nothing */
  67   /* Same if the channel is still present on the network */
  68
  69   if (cip->channel!=NULL) {
  70     return;
  71   }
  72
  73   for (i=0;i<MAXCHANNELEXTS;i++) {
  74     if (cip->exts[i]!=NULL) {
  75       return;
  76     }
  77   }
  78
  79   /* Now remove the index record from the index. */
  80   hash=channelhash(cip->name->content);
  81
  82   for(cih=&(chantable[hash]);*cih;cih=&((*cih)->next)) {
  83     if (*cih==cip) {
  84       (*cih)=cip->next;
  85       freesstring(cip->name);
  86       freechanindex(cip);
  87       return;
  88     }
  89   }
  90
  91   Error("channel",ERR_ERROR,"Tried to release chanindex record for %s not found in hash",cip->name->content);
  92 }
  93
  94 int registerchanext(const char *name) {
  95   int i;
  96
  97   if (findchanext(name)!=-1) {
  98     Error("channel",ERR_WARNING,"Tried to register duplicate extension %s",name);
  99     return -1;
 100   }
 101
 102   for (i=0;i<MAXCHANNELEXTS;i++) {
 103     if (extnames[i]==NULL) {
 104       extnames[i]=getsstring(name,100);
 105       return i;
 106     }
 107   }
 108
 109   Error("channel",ERR_WARNING,"Tried to register too many extensions: %s",name);
 110   return -1;
 111 }
 112
 113 int findchanext(const char *name) {
 114   int i;
 115
 116   for (i=0;i<MAXCHANNELEXTS;i++) {
 117     if (extnames[i]!=NULL && !ircd_strcmp(name,extnames[i]->content)) {
 118       return i;
 119     }
 120   }
 121
 122   return -1;
 123 }
 124
 125 void releasechanext(int index) {
 126   int i;
 127   chanindex *cip,*ncip;
 128
 129   freesstring(extnames[index]);
 130   extnames[index]=NULL;
 131
 132   for (i=0;i<CHANNELHASHSIZE;i++) {
 133     for (cip=chantable[i];cip;cip=ncip) {
 134       /* CAREFUL: deleting items from chains you're walking is bad */
 135       ncip=cip->next;
 136       if (cip->exts[index]!=NULL) {
 137         cip->exts[index]=NULL;
 138         releasechanindex(cip);
 139       }
 140     }
 141   }
 142 }
 143
 144 unsigned int nextchanmarker() {
 145   int i;
 146   chanindex *cip;
 147
 148   channelmarker++;
 149   if (!channelmarker) {
 150     /* If we wrapped to zero, zap the marker on all records */
 151     for (i=0;i<CHANNELHASHSIZE;i++)
 152       for (cip=chantable[i];cip;cip=cip->next)
 153         cip->marker=0;
 154     channelmarker++;
 155   }
 156
 157   return channelmarker;
 158 }