ref: a291bbdeddfd41a2f0907ecbd7b819f0eedffdaf
dir: /sys/src/cmd/mk/symtab.c/
#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); }