channel/channelalloc.c

   1 /* channelalloc.c */
   2
   3 #include <stdlib.h>
   4 #include "channel.h"
   5 #include <assert.h>
   6 #include "../core/nsmalloc.h"
   7
   8 #define ALLOCUNIT  100
   9
  10 channel *freechans;
  11 chanuserhash *freehash;
  12
  13 void initchannelalloc() {
  14   freechans=NULL;
  15   freehash=NULL;
  16 }
  17
  18 /* channel records don't have next pointers.
  19  * Overload the index pointer for chaining free channels */
  20
  21 channel *newchan() {
  22   int i;
  23   channel *cp;
  24
  25   if (freechans==NULL) {
  26     freechans=(channel *)nsmalloc(POOL_CHANNEL,ALLOCUNIT*sizeof(channel));
  27     for (i=0;i<(ALLOCUNIT-1);i++) {
  28       freechans[i].index=(struct chanindex *)&(freechans[i+1]);
  29     }
  30     freechans[ALLOCUNIT-1].index=NULL;
  31   }
  32
  33   cp=freechans;
  34   freechans=(channel *)cp->index;
  35
  36   return cp;
  37 }
  38
  39 void freechan(channel *cp) {
  40   cp->index=(struct chanindex *)freechans;
  41   freechans=cp;
  42 }
  43
  44 /*
  45  * Free hash for all!
  46  *
  47  * Since these things don't naturally have a "next" pointer
  48  * we abuse the "content" pointer to build our list of free
  49  * structures.
  50  *
  51  * Hence some somewhat bizarre casts...
  52  */
  53
  54 chanuserhash *newchanuserhash(int hashsize) {
  55   int i;
  56   chanuserhash *cuhp;
  57
  58   if (freehash==NULL) {
  59     freehash=(chanuserhash *)nsmalloc(POOL_CHANNEL,ALLOCUNIT*sizeof(chanuserhash));
  60     for (i=0;i<(ALLOCUNIT-1);i++) {
  61       freehash[i].content=(unsigned long *)&(freehash[i+1]);
  62     }
  63     freehash[ALLOCUNIT-1].content=NULL;
  64   }
  65
  66   cuhp=freehash;
  67   freehash=(chanuserhash *)cuhp->content;
  68
  69   /* Don't use nsmalloc() here since we will free this in freechanuserhash() */
  70   cuhp->content=(unsigned long *)malloc(hashsize*sizeof(unsigned long));
  71   for (i=0;i<hashsize;i++) {
  72     cuhp->content[i]=nouser;
  73   }
  74
  75   cuhp->hashsize=hashsize;
  76   cuhp->totalusers=0;
  77
  78   return cuhp;
  79 }
  80
  81 void freechanuserhash(chanuserhash *cuhp) {
  82   free(cuhp->content);
  83   cuhp->content=(unsigned long *)freehash;
  84   freehash=cuhp;
  85 }