chanindex/chanindex.c

   1 /* channelindex.c */
   2
   3 #include "chanindex.h"
   4 #include "../irc/irc_config.h"
   5 #include "../lib/irc_string.h"
   6 #include "../core/error.h"
   7 #include "../core/nsmalloc.h"
   8
   9 #include <stdio.h>
  10 #include <string.h>
  11
  12 #define ALLOCUNIT       1000
  13
  14 #define channelhash(x)  (crc32i(x)%CHANNELHASHSIZE)
  15
  16 chanindex *chantable[CHANNELHASHSIZE];
  17 sstring *extnames[MAXCHANNELEXTS];
  18 chanindex *freechanindices;
  19
  20 unsigned int channelmarker;
  21
  22 void _init() {
  23   memset(chantable,0,sizeof(chantable));
  24   memset(extnames,0,sizeof(extnames));
  25   channelmarker=0;
  26   freechanindices=NULL;
  27 }
  28
  29 void _fini() {
  30   nsfreeall(POOL_CHANINDEX);
  31 }
  32
  33 chanindex *getchanindex() {
  34   int i;
  35   chanindex *cip;
  36
  37   if (freechanindices==NULL) {
  38     freechanindices=(chanindex *)nsmalloc(POOL_CHANINDEX, ALLOCUNIT*sizeof(chanindex));
  39     for(i=0;i<ALLOCUNIT-1;i++) {
  40       freechanindices[i].next=&(freechanindices[i+1]);
  41     }
  42     freechanindices[ALLOCUNIT-1].next=NULL;
  43   }
  44
  45   cip=freechanindices;
  46   freechanindices=cip->next;
  47
  48   return cip;
  49 }
  50
  51 void freechanindex(chanindex *cip) {
  52   cip->next=freechanindices;
  53   freechanindices=cip;
  54 }
  55
  56 chanindex *findchanindex(const char *name) {
  57   chanindex *cip;
  58   int hash=channelhash(name);
  59
  60   for (cip=chantable[hash];cip;cip=cip->next) {
  61     if (!ircd_strcmp(cip->name->content,name)) {
  62       return cip;
  63     }
  64   }
  65
  66   return NULL;
  67 }
  68
  69 chanindex *findorcreatechanindex(const char *name) {
  70   chanindex *cip;
  71   int hash=channelhash(name);
  72   int i;
  73
  74   for (cip=chantable[hash];cip;cip=cip->next) {
  75     if (!ircd_strcmp(cip->name->content,name)) {
  76       return cip;
  77     }
  78   }
  79
  80   cip=getchanindex();
  81
  82   cip->name=getsstring(name,CHANNELLEN);
  83   cip->channel=NULL;
  84   cip->marker=0;
  85   cip->next=chantable[hash];
  86   chantable[hash]=cip;
  87
  88   for(i=0;i<MAXCHANNELEXTS;i++) {
  89     cip->exts[i]=NULL;
  90   }
  91
  92   return cip;
  93 }
  94
  95 void releasechanindex(chanindex *cip) {
  96   int i;
  97   chanindex **cih;
  98   int hash;
  99
 100   /* If any module is still using the channel, do nothing */
 101   /* Same if the channel is still present on the network */
 102
 103   if (cip->channel!=NULL) {
 104     return;
 105   }
 106
 107   for (i=0;i<MAXCHANNELEXTS;i++) {
 108     if (cip->exts[i]!=NULL) {
 109       return;
 110     }
 111   }
 112
 113   /* Now remove the index record from the index. */
 114   hash=channelhash(cip->name->content);
 115
 116   for(cih=&(chantable[hash]);*cih;cih=&((*cih)->next)) {
 117     if (*cih==cip) {
 118       (*cih)=cip->next;
 119       freesstring(cip->name);
 120       freechanindex(cip);
 121       return;
 122     }
 123   }
 124
 125   Error("channel",ERR_ERROR,"Tried to release chanindex record for %s not found in hash",cip->name->content);
 126 }
 127
 128 int registerchanext(const char *name) {
 129   int i;
 130
 131   if (findchanext(name)!=-1) {
 132     Error("channel",ERR_WARNING,"Tried to register duplicate extension %s",name);
 133     return -1;
 134   }
 135
 136   for (i=0;i<MAXCHANNELEXTS;i++) {
 137     if (extnames[i]==NULL) {
 138       extnames[i]=getsstring(name,100);
 139       return i;
 140     }
 141   }
 142
 143   Error("channel",ERR_WARNING,"Tried to register too many extensions: %s",name);
 144   return -1;
 145 }
 146
 147 int findchanext(const char *name) {
 148   int i;
 149
 150   for (i=0;i<MAXCHANNELEXTS;i++) {
 151     if (extnames[i]!=NULL && !ircd_strcmp(name,extnames[i]->content)) {
 152       return i;
 153     }
 154   }
 155
 156   return -1;
 157 }
 158
 159 void releasechanext(int index) {
 160   int i;
 161   chanindex *cip,*ncip;
 162
 163   freesstring(extnames[index]);
 164   extnames[index]=NULL;
 165
 166   for (i=0;i<CHANNELHASHSIZE;i++) {
 167     for (cip=chantable[i];cip;cip=ncip) {
 168       /* CAREFUL: deleting items from chains you're walking is bad */
 169       ncip=cip->next;
 170       if (cip->exts[index]!=NULL) {
 171         cip->exts[index]=NULL;
 172         releasechanindex(cip);
 173       }
 174     }
 175   }
 176 }
 177
 178 unsigned int nextchanmarker() {
 179   int i;
 180   chanindex *cip;
 181
 182   channelmarker++;
 183   if (!channelmarker) {
 184     /* If we wrapped to zero, zap the marker on all records */
 185     for (i=0;i<CHANNELHASHSIZE;i++)
 186       for (cip=chantable[i];cip;cip=cip->next)
 187         cip->marker=0;
 188     channelmarker++;
 189   }
 190
 191   return channelmarker;
 192 }