forsyth20121205-174063a80cc13 years agoHistory
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#include	"mk.h" #define	NHASH	4099#define	HASHMUL	79L	/* this is a good value */static Symtab *hash[NHASH]; voidsyminit(void){	Symtab **s, *ss, *next; 	for(s = hash; s < &hash[NHASH]; s++){		for(ss = *s; ss; ss = next){			next = 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);} voidsymdel(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);		}} voidsymtraverse(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);} voidsymstat(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);}