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#include "mk.h"
#define NHASH 4099
#define HASHMUL 79L /* this is a good value */
static Symtab *hash[NHASH];
void
syminit(void)
{
Symtab **s, *ss;
for(s = hash; s < &hash[NHASH]; s++){
for(ss = *s; ss; ss = ss->next)
free((char *)ss);
*s = 0;
}
}
Symtab *
symlook(char *sym, int space, void *install)
{
long h;
char *p;
Symtab *s;
for(p = sym, h = space; *p; h += *p++)
h *= HASHMUL;
if(h < 0)
h = ~h;
h %= NHASH;
for(s = hash[h]; s; s = s->next)
if((s->space == space) && (strcmp(s->name, sym) == 0))
return(s);
if(install == 0)
return(0);
s = (Symtab *)Malloc(sizeof(Symtab));
s->space = space;
s->name = sym;
s->value = install;
s->next = hash[h];
hash[h] = s;
return(s);
}
void
symdel(char *sym, int space)
{
long h;
char *p;
Symtab *s, *ls;
/* multiple memory leaks */
for(p = sym, h = space; *p; h += *p++)
h *= HASHMUL;
if(h < 0)
h = ~h;
h %= NHASH;
for(s = hash[h], ls = 0; s; ls = s, s = s->next)
if((s->space == space) && (strcmp(s->name, sym) == 0)){
if(ls)
ls->next = s->next;
else
hash[h] = s->next;
free((char *)s);
}
}
void
symtraverse(int space, void (*fn)(Symtab*))
{
Symtab **s, *ss;
for(s = hash; s < &hash[NHASH]; s++)
for(ss = *s; ss; ss = ss->next)
if(ss->space == space)
(*fn)(ss);
}
void
symstat(void)
{
Symtab **s, *ss;
int n;
int l[1000];
memset((char *)l, 0, sizeof(l));
for(s = hash; s < &hash[NHASH]; s++){
for(ss = *s, n = 0; ss; ss = ss->next)
n++;
l[n]++;
}
for(n = 0; n < 1000; n++)
if(l[n]) Bprint(&bout, "%ld of length %d\n", l[n], n);
}
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