rewrite hash map

map.c

@@ -2,11 +2,12 @@
 
 #include <stdlib.h>
 #include <assert.h>
+#include <stdio.h>
 
 struct node {
 	int fd;
 	int id;
-	int next;
+	struct node * next;
 };
 
 struct map {
@@ -27,7 +28,7 @@ map_new(int max) {
 	for (i=0;i<sz;i++) {
 		m->hash[i].fd = -1;
 		m->hash[i].id = 0;
-		m->hash[i].next = -1;
+		m->hash[i].next = NULL;
 	}
 	return m;
 }
@@ -42,30 +43,40 @@ int
 map_search(struct map * m, int fd) {
 	int hash = fd & (m->size-1);
 	struct node * n = &m->hash[hash];
-	for(;;) {
+	do {
 		if (n->fd == fd)
 			return n->id;
-		if (n->next < 0)
-			return -1;
-		n = &m->hash[n->next];
-	}
+		n = n->next;
+	} while(n);
+	return -1;
 }
 
 void 
 map_insert(struct map * m, int fd, int id) {
 	int hash = fd & (m->size-1);
 	struct node * n = &m->hash[hash];
-	for (;;) {
-		if (n->fd < 0) {
-			n->fd = fd;
-			n->id = id;
-			return;
-		}
-		if (n->next < 0 ) {
-			break;
+	if (n->fd < 0) {
+		n->fd = fd;
+		n->id = id;
+		return;
+	}
+	int ohash = n->fd & (m->size-1);
+	if (hash != ohash) {
+		struct node * last = &m->hash[ohash];
+		while (last->next != &m->hash[hash]) {
+			last = last->next;
 		}
-		n = &m->hash[n->next];
+		last->next = n->next;
+
+		int ofd = n->fd;
+		int oid = n->id;
+		n->fd = fd;
+		n->id = id;
+		n->next = NULL;
+		map_insert(m,ofd, oid);
+		return;
 	}
+
 	int last = (n - m->hash) * 2;
 	int i;
 	for (i=0;i<m->size;i++) {
@@ -74,7 +85,8 @@ map_insert(struct map * m, int fd, int id) {
 		if (temp->fd < 0) {
 			temp->fd = fd;
 			temp->id = id;
-			n->next = idx;
+			temp->next = n->next;
+			n->next = temp;
 			return;
 		}
 	}
@@ -85,13 +97,43 @@ void
 map_erase(struct map *m , int fd) {
 	int hash = fd & (m->size-1);
 	struct node * n = &m->hash[hash];
+	if (n->fd == fd) {
+		if (n->next == NULL) {
+			n->fd = -1;
+			return;
+		}
+		struct node * next = n->next;
+		n->fd = next->fd;
+		n->id = next->id;
+		n->next = next->next;
+		next->fd = -1;
+		next->next = NULL;
+		return;
+	}
+	if (n->next == NULL) {
+		return;
+	}
+	struct node * last = n;
+	n = n->next;
 	for(;;) {
 		if (n->fd == fd) {
 			n->fd = -1;
+			last->next = n->next;
+			n->next = NULL;
 			return;
 		}
-		if (n->next < 0)
+		if (n->next == NULL)
 			return;
-		n = &m->hash[n->next];
+		last = n;
+		n = n->next;
 	}
 }
+
+void
+map_dump(struct map *m) {
+	int i;
+	for (i=0;i<m->size;i++) {
+		struct node * n = &(m->hash[i]);
+		printf("[%d] fd = %d , id = %d , next = %d\n",i,n->fd,n->id,(n->next - m->hash));
+	}
+}

map.h

@@ -8,5 +8,6 @@ void map_delete(struct map *);
 int map_search(struct map * , int fd);
 void map_insert(struct map * , int fd, int id);
 void map_erase(struct map *, int fd);
+void map_dump(struct map *m);
 
 #endif

testmap.c

@@ -4,21 +4,21 @@
 #include <assert.h>
 #include <stdio.h>
 
-#define MAX 1000
+#define MAX 2000
 
 static void
 test(struct map *m) {
 	int a[MAX * 2];
 	int i;
 	int s = 0;
 	for (i=0;i<MAX*2;i++) {
-		int inc = random() % 3 + 1;
+		int inc = rand() % 3 + 1;
 		s += inc;
 		a[i] = s;
 	}
 	for (i=0;i<MAX * 2;i++) {
-		int x = random()%(MAX*2);
-		int y = random()%(MAX*2);
+		int x = rand()%(MAX*2);
+		int y = rand()%(MAX*2);
 		int temp = a[x];
 		a[x] = a[y];
 		a[y] = temp;
@@ -34,15 +34,12 @@ test(struct map *m) {
 		map_erase(m, a[i]);
 	}
 	for (i=0;i<MAX/2;i++) {
-		map_insert(m,a[i+MAX],i);
+		a[i] = a[i+MAX];
+		map_insert(m,a[i],i);
 	}
 	for (i=0;i<MAX;i++) {
-		int id = map_search(m,a[i+MAX/2]);
-		if (i>=MAX/2) {
-			assert(id == i - MAX/2);
-		} else {
-			assert(id == i + MAX/2);
-		}
+		int id = map_search(m,a[i]);
+		assert(id == i);
 	}
 }