Subversion Repositories planix.SVN

#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->u.ptr = 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, "%d of length %d\n", l[n], n);
}