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// Copyright 2011 The Closure Library Authors. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//      http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS-IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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/**
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 * @fileoverview Abstract cryptographic hash interface.
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 *
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 * See goog.crypt.Sha1 and goog.crypt.Md5 for sample implementations.
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 *
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 */
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goog.provide('goog.crypt.Hash');
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/**
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 * Create a cryptographic hash instance.
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 *
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 * @constructor
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 * @struct
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 */
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goog.crypt.Hash = function() {
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  /**
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   * The block size for the hasher.
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   * @type {number}
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   */
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  this.blockSize = -1;
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};
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/**
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 * Resets the internal accumulator.
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 */
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goog.crypt.Hash.prototype.reset = goog.abstractMethod;
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/**
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 * Adds a byte array (array with values in [0-255] range) or a string (must
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 * only contain 8-bit, i.e., Latin1 characters) to the internal accumulator.
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 *
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 * Many hash functions operate on blocks of data and implement optimizations
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 * when a full chunk of data is readily available. Hence it is often preferable
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 * to provide large chunks of data (a kilobyte or more) than to repeatedly
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 * call the update method with few tens of bytes. If this is not possible, or
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 * not feasible, it might be good to provide data in multiplies of hash block
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 * size (often 64 bytes). Please see the implementation and performance tests
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 * of your favourite hash.
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 *
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 * @param {Array<number>|Uint8Array|string} bytes Data used for the update.
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 * @param {number=} opt_length Number of bytes to use.
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 */
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goog.crypt.Hash.prototype.update = goog.abstractMethod;
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/**
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 * @return {!Array<number>} The finalized hash computed
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 *     from the internal accumulator.
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 */
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goog.crypt.Hash.prototype.digest = goog.abstractMethod;
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