Keep peers in a hash table to allow fast address lookups

1 files changed, 47 insertions, 0 deletions

diff --git a/src/hash.h b/src/hash.h
new file mode 100644
index 0000000..7a47388
--- /dev/null
+++ b/src/hash.h
@@ -0,0 +1,47 @@
+/*
+  Copyright (c) 2012-2014, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+
+#include <stddef.h>
+#include <stdint.h>
+
+
+static inline void fastd_hash(uint32_t *hash, const void *data, size_t len) {
+	size_t i;
+	for (i = 0; i < len; ++i) {
+		*hash += ((uint8_t*)data)[i];
+		*hash += (*hash << 10);
+		*hash ^= (*hash >> 6);
+	}
+}
+
+static inline void fastd_hash_final(uint32_t *hash) {
+	*hash += (*hash << 3);
+	*hash ^= (*hash >> 11);
+	*hash += (*hash << 15);
+}