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