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	The loop in HashBytes currently hashes both a word of data (as intended) and the length of that word of data (a constant). This was [acknowledged as a bug](https://bugzilla.mozilla.org/show_bug.cgi?id=729940#c49) when first written, but slipped through the cracks and was never fixed. Differential Revision: https://phabricator.services.mozilla.com/D119466
		
			
				
	
	
		
			37 lines
		
	
	
	
		
			1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			37 lines
		
	
	
	
		
			1 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set ts=8 sts=2 et sw=2 tw=80: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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 * License, v. 2.0. If a copy of the MPL was not distributed with this
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 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/* Implementations of hash functions. */
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#include "mozilla/HashFunctions.h"
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#include "mozilla/Types.h"
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#include <string.h>
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namespace mozilla {
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uint32_t HashBytes(const void* aBytes, size_t aLength) {
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  uint32_t hash = 0;
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  const char* b = reinterpret_cast<const char*>(aBytes);
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  /* Walk word by word. */
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  size_t i = 0;
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  for (; i < aLength - (aLength % sizeof(size_t)); i += sizeof(size_t)) {
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    /* Do an explicitly unaligned load of the data. */
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    size_t data;
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    memcpy(&data, b + i, sizeof(size_t));
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    hash = AddToHash(hash, data);
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  }
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  /* Get the remaining bytes. */
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  for (; i < aLength; i++) {
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    hash = AddToHash(hash, b[i]);
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  }
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  return hash;
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}
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} /* namespace mozilla */
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