1 /* 2 * Copyright 2013 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkSHA1_DEFINED 9 #define SkSHA1_DEFINED 10 11 #include "SkTypes.h" 12 #include "SkEndian.h" 13 #include "SkStream.h" 14 15 //The following macros can be defined to affect the SHA1 code generated. 16 //SK_SHA1_CLEAR_DATA causes all intermediate state to be overwritten with 0's. 17 //SK_CPU_BENDIAN allows 32 bit <=> 8 bit conversions without copies (if alligned). 18 //SK_CPU_FAST_UNALIGNED_ACCESS allows 32 bit <=> 8 bit conversions without copies if SK_CPU_BENDIAN. 19 20 class SkSHA1 : public SkWStream { 21 public: 22 SkSHA1(); 23 24 /** Processes input, adding it to the digest. 25 * Note that this treats the buffer as a series of uint8_t values. 26 */ 27 virtual bool write(const void* buffer, size_t size) SK_OVERRIDE { 28 update(reinterpret_cast<const uint8_t*>(buffer), size); 29 return true; 30 } 31 32 virtual size_t bytesWritten() const SK_OVERRIDE { return SkToSizeT(this->byteCount); } 33 34 /** Processes input, adding it to the digest. Calling this after finish is undefined. */ 35 void update(const uint8_t* input, size_t length); 36 37 struct Digest { 38 uint8_t data[20]; 39 }; 40 41 /** Computes and returns the digest. */ 42 void finish(Digest& digest); 43 44 private: 45 // number of bytes, modulo 2^64 46 uint64_t byteCount; 47 48 // state (ABCDE) 49 uint32_t state[5]; 50 51 // input buffer 52 uint8_t buffer[64]; 53 }; 54 55 #endif 56
