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-rw-r--r--mfbt/HashFunctions.cpp39
1 files changed, 39 insertions, 0 deletions
diff --git a/mfbt/HashFunctions.cpp b/mfbt/HashFunctions.cpp
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+++ b/mfbt/HashFunctions.cpp
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Implementations of hash functions. */
+
+#include "mozilla/HashFunctions.h"
+#include "mozilla/Types.h"
+
+#include <string.h>
+
+namespace mozilla {
+
+uint32_t
+HashBytes(const void* aBytes, size_t aLength)
+{
+ uint32_t hash = 0;
+ const char* b = reinterpret_cast<const char*>(aBytes);
+
+ /* Walk word by word. */
+ size_t i = 0;
+ for (; i < aLength - (aLength % sizeof(size_t)); i += sizeof(size_t)) {
+ /* Do an explicitly unaligned load of the data. */
+ size_t data;
+ memcpy(&data, b + i, sizeof(size_t));
+
+ hash = AddToHash(hash, data, sizeof(data));
+ }
+
+ /* Get the remaining bytes. */
+ for (; i < aLength; i++) {
+ hash = AddToHash(hash, b[i]);
+ }
+ return hash;
+}
+
+} /* namespace mozilla */