first commit

hash.c

@@ -0,0 +1,129 @@
+#include "dat.h"
+#include "fn.h"
+
+enum {
+	Tagsize = sizeof(Hnode),
+};
+
+static uvlong
+hash(Str *s)
+{
+	uvlong h;
+	int i;
+
+	h = 7;
+	for(i = 0; i < s->n; i++)
+		h = h*31 + s->r[i];
+	return h;
+}
+
+Hmap*
+hmapalloc(int nbuckets, int size)
+{
+	void *store;
+	Hmap *h;
+	int nsz;
+
+	nsz = Tagsize + size;
+	store = emalloc(sizeof(*h) + nbuckets * nsz);
+	h = store;
+	h->nbs = nbuckets;
+	h->nsz = nsz;
+	h->len = h->cap = nbuckets;
+	h->nodes = (uchar*)store + sizeof(*h);
+	return h;
+}
+
+static int
+keycmp(Hnode *n, Str *key)
+{
+	char buf[256];
+	int len;
+
+	len = stoutf(key, buf, sizeof(buf));
+	if(n->klen != len)
+		return 1;
+	return memcmp(n->key, buf, len);
+}
+
+Hnode*
+hmapget(Hmap *h, Str *key)
+{
+	Hnode *n;
+	uchar *v;
+
+	v = h->nodes + (hash(key) % h->nbs) * h->nsz;
+	for(;;){
+		n = (Hnode*)v;
+		if(n->filled && keycmp(n, key) == 0)
+			return n;
+		if(n->next == 0)
+			break;
+		v = h->nodes + n->next * h->nsz;
+	}
+	return nil;
+}
+
+static char*
+str2dup(Str *s)
+{
+	char buf[256];
+	char *p;
+	int n;
+
+	n = stoutf(s, buf, sizeof(buf));
+	p = emalloc(n + 1);
+	memmove(p, buf, n);
+	p[n] = '\0';
+	return p;
+}
+
+int
+hmapset(Hmap **store, Str *key, Str *kana)
+{
+	Hnode *n;
+	uchar *v;
+	Hmap *h;
+	int next;
+	vlong diff;
+
+	h = *store;
+	v = h->nodes + (hash(key) % h->nbs) * h->nsz;
+	for(;;){
+		n = (Hnode*)v;
+		next = n->next;
+		if(n->filled == 0)
+			goto replace;
+		if(keycmp(n, key) == 0)
+			goto replace;
+		if(next == 0)
+			break;
+		v = h->nodes + next * h->nsz;
+	}
+	if(h->cap == h->len){
+		diff = v - h->nodes;
+		h->cap *= 2;
+		*store = erealloc(*store, sizeof(*h) + h->cap * h->nsz);
+		h = *store;
+		h->nodes = (uchar*)*store + sizeof(*h);
+		v = h->nodes + diff;
+		n = (Hnode*)v;
+	}
+	n->next = h->len;
+	memset(h->nodes + h->len * h->nsz, 0, h->nsz);
+	h->len++;
+	v = h->nodes + n->next * h->nsz;
+	n = (Hnode*)v;
+replace:
+	if(n->filled == 0){
+		n->key = str2dup(key);
+		n->klen = strlen(n->key);
+		n->filled = 1;
+	}
+	n->next = next;
+	if(kana->n > 0){
+		n->kana = str2dup(kana);
+		n->kanalen = strlen(n->kana);
+	}
+	return 0;
+}