... and in with the New ...

CVS patchset: 7471
CVS date: 2004/10/16 01:31:54

1 files changed, 137 insertions, 0 deletions

diff --git a/db/mod_db4/mm_hash.c b/db/mod_db4/mm_hash.c
new file mode 100644
index 000000000..f42409c93
--- /dev/null
+++ b/db/mod_db4/mm_hash.c
@@ -0,0 +1,137 @@
+/*-
+ *  Copyright (c) 2004
+ *  Sleepycat Software.  All rights reserved.
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0.txt
+ * 
+ *  authors: Thies C. Arntzen <thies@php.net>
+ *           Sterling Hughes <sterling@php.net>
+ *           George Schlossnagle <george@omniti.com>
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include "mm_hash.h"
+
+MM_Hash *mm_hash_new(MM *mm, MM_HashDtor dtor)
+{
+	MM_Hash *table;
+
+	table = mm_calloc(mm, 1, sizeof(MM_Hash));
+	table->mm = mm;
+	table->dtor = dtor;
+
+	return table;
+}
+
+void mm_hash_free(MM_Hash *table) 
+{
+	MM_Bucket *cur;
+	MM_Bucket *next;
+	int     i;
+
+	for (i = 0; i < MM_HASH_SIZE; i++) {
+		cur = table->buckets[i];
+		while (cur) {
+			next = cur->next;
+
+			if (table->dtor) table->dtor(cur->data);
+			mm_free(table->mm, cur->key);
+			mm_free(table->mm, cur);
+
+			cur = next;
+		}
+	}
+	mm_free(table->mm, table);
+}
+
+static unsigned int hash_hash(const char *key, int length)
+{
+    unsigned int hash = 0;
+
+    while (--length)
+        hash = hash * 65599 + *key++;
+
+    return hash;
+}
+
+void *mm_hash_find(MM_Hash *table, const void *key, int length)
+{
+	MM_Bucket       *b;
+	unsigned int  hash = hash_hash(key, length) % MM_HASH_SIZE;
+
+    for (b = table->buckets[ hash ]; b; b = b->next) {
+		if (hash != b->hash) continue;
+		if (length != b->length) continue;
+		if (memcmp(key, b->key, length)) continue;
+
+		return b->data;
+    }
+
+    return NULL;
+}
+
+void mm_hash_update(MM_Hash *table, char *key, int length, void *data)
+{
+	MM_Bucket *b, p;
+	unsigned int  hash;
+	
+	hash = hash_hash(key, length) % MM_HASH_SIZE;
+
+	for(b = table->buckets[ hash ]; b; b = b->next) {
+		if (hash != b->hash) continue;
+		if (length != b->length) continue;
+		if (memcmp(key, b->key, length)) continue;
+		if (table->dtor) table->dtor(b->data);
+		b->data = data;
+	}
+	if(!b) {
+    	b = mm_malloc(table->mm, sizeof(MM_Bucket));
+    	b->key = mm_malloc(table->mm, length + 1);
+    	memcpy(b->key, key, length);
+    	b->key[length] = 0;
+    	b->length = length;
+    	b->hash = hash;
+    	b->data = data;
+		b->next = table->buckets[ hash ];
+		table->buckets[ hash ] = b;
+	}	
+	table->nElements++;
+}
+
+void mm_hash_delete(MM_Hash *table, char *key, int length)
+{
+	MM_Bucket       *b; 
+	MM_Bucket       *prev = NULL;
+	unsigned int  hash;
+
+	hash = hash_hash(key, length) % MM_HASH_SIZE;
+    for (b = table->buckets[ hash ]; b; b = b->next) {
+		if (hash != b->hash || length != b->length || memcmp(key, b->key, length)) {
+			prev = b;
+			continue;
+		}
+
+		/* unlink */
+		if (prev) {
+			prev->next = b->next;
+		} else {
+			table->buckets[hash] = b->next;
+		}
+		
+		if (table->dtor) table->dtor(b->data);
+		mm_free(table->mm, b->key);
+		mm_free(table->mm, b);
+
+		break;
+    }
+}
+
+/*
+Local variables:
+tab-width: 4
+c-basic-offset: 4
+End:
+vim600: noet sw=4 ts=4 fdm=marker
+vim<600: noet sw=4 ts=4
+*/