core/nsmalloc.c

   1 /* nsmalloc: Simple pooled malloc() thing. */
   2
   3 #include <stdlib.h>
   4
   5 #include "nsmalloc.h"
   6 #include "../core/error.h"
   7
   8 void *nsmalloc(unsigned int poolid, size_t size);
   9 void nsfree(unsigned int poolid, void *ptr);
  10 void nsfreeall(unsigned int poolid);
  11
  12 struct nsminfo {
  13   struct nsminfo *next;
  14   union {
  15     struct nsminfo *prev;
  16     unsigned long count;
  17   } p;
  18
  19   size_t size;
  20   char data[];
  21 };
  22
  23 struct nsminfo pools[MAXPOOL];
  24
  25 void *nsmalloc(unsigned int poolid, size_t size) {
  26   struct nsminfo *nsmp;
  27
  28   if (poolid >= MAXPOOL)
  29     return NULL;
  30
  31   /* Allocate enough for the structure and the required data */
  32   nsmp=(struct nsminfo *)malloc(sizeof(struct nsminfo)+size);
  33
  34   if (!nsmp)
  35     return NULL;
  36
  37   nsmp->size=size;
  38   pools[poolid].size+=size;
  39   pools[poolid].p.count++;
  40
  41   nsmp->next=pools[poolid].next;
  42   nsmp->p.prev=&pools[poolid];
  43   if (pools[poolid].next)
  44     pools[poolid].next->p.prev=nsmp;
  45   pools[poolid].next=nsmp;
  46
  47   return (void *)nsmp->data;
  48 }
  49
  50 /* we dump core on ptr == NULL */
  51 void nsfree(unsigned int poolid, void *ptr) {
  52   struct nsminfo *nsmp;
  53
  54   if (poolid >= MAXPOOL)
  55     return;
  56
  57   /* evil */
  58   nsmp=(struct nsminfo*)ptr - 1;
  59
  60   /* always set as we have a sentinel */
  61   nsmp->p.prev->next=nsmp->next;
  62   if (nsmp->next)
  63     nsmp->next->p.prev=nsmp->p.prev;
  64
  65   pools[poolid].size-=nsmp->size;
  66   pools[poolid].p.count--;
  67
  68   free(nsmp);
  69   return;
  70 }
  71
  72 void *nsrealloc(unsigned int poolid, void *ptr, size_t size) {
  73   struct nsminfo *nsmp, *nsmpn;
  74
  75   if (ptr == NULL)
  76     return nsmalloc(poolid, size);
  77
  78   if (size == 0) {
  79     nsfree(poolid, ptr);
  80     return NULL;
  81   }
  82
  83   if (poolid >= MAXPOOL)
  84     return NULL;
  85
  86   /* evil */
  87   nsmp=(struct nsminfo *)ptr - 1;
  88
  89   if (size == nsmp->size)
  90     return (void *)nsmp->data;
  91
  92   nsmpn=(struct nsminfo *)realloc(nsmp, sizeof(struct nsminfo)+size);
  93   if (!nsmpn)
  94     return NULL;
  95
  96   pools[poolid].size+=size-nsmpn->size;
  97   nsmpn->size=size;
  98
  99   /* always set as we have a sentinel */
 100   nsmpn->p.prev->next=nsmpn;
 101
 102   if (nsmpn->next)
 103     nsmpn->next->p.prev=nsmpn;
 104
 105   return (void *)nsmpn->data;
 106 }
 107
 108 void nsfreeall(unsigned int poolid) {
 109   struct nsminfo *nsmp, *nnsmp;
 110
 111   if (poolid >= MAXPOOL)
 112     return;
 113
 114   for (nsmp=pools[poolid].next;nsmp;nsmp=nnsmp) {
 115     nnsmp=nsmp->next;
 116     free(nsmp);
 117   }
 118
 119   pools[poolid].next=NULL;
 120   pools[poolid].size=0;
 121   pools[poolid].p.count=0;
 122 }
 123
 124 void nsexit() {
 125   unsigned int i;
 126
 127   for (i=0;i<MAXPOOL;i++) {
 128     if (pools[i].next) {
 129       Error("core",ERR_INFO,"nsmalloc: Blocks still allocated in pool #%d (%lub, %lu items)\n",i,pools[i].size, pools[i].p.count);
 130       nsfreeall(i);
 131     }
 132   }
 133 }
 134
 135 int nspoolstats(unsigned int poolid, size_t *size, unsigned long *count) {
 136   if (poolid >= MAXPOOL)
 137     return 0;
 138
 139   *size = pools[poolid].size;
 140   *count = pools[poolid].p.count;
 141
 142   return 1;
 143 }