michael@0: /*
michael@0:  * Copyright 2013 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #ifndef SkSHA1_DEFINED
michael@0: #define SkSHA1_DEFINED
michael@0: 
michael@0: #include "SkTypes.h"
michael@0: #include "SkEndian.h"
michael@0: #include "SkStream.h"
michael@0: 
michael@0: //The following macros can be defined to affect the SHA1 code generated.
michael@0: //SK_SHA1_CLEAR_DATA causes all intermediate state to be overwritten with 0's.
michael@0: //SK_CPU_BENDIAN allows 32 bit <=> 8 bit conversions without copies (if alligned).
michael@0: //SK_CPU_FAST_UNALIGNED_ACCESS allows 32 bit <=> 8 bit conversions without copies if SK_CPU_BENDIAN.
michael@0: 
michael@0: class SkSHA1 : public SkWStream {
michael@0: public:
michael@0:     SkSHA1();
michael@0: 
michael@0:     /** Processes input, adding it to the digest.
michael@0:      *  Note that this treats the buffer as a series of uint8_t values.
michael@0:      */
michael@0:     virtual bool write(const void* buffer, size_t size) SK_OVERRIDE {
michael@0:         update(reinterpret_cast<const uint8_t*>(buffer), size);
michael@0:         return true;
michael@0:     }
michael@0: 
michael@0:     virtual size_t bytesWritten() const SK_OVERRIDE { return SkToSizeT(this->byteCount); }
michael@0: 
michael@0:     /** Processes input, adding it to the digest. Calling this after finish is undefined. */
michael@0:     void update(const uint8_t* input, size_t length);
michael@0: 
michael@0:     struct Digest {
michael@0:         uint8_t data[20];
michael@0:     };
michael@0: 
michael@0:     /** Computes and returns the digest. */
michael@0:     void finish(Digest& digest);
michael@0: 
michael@0: private:
michael@0:     // number of bytes, modulo 2^64
michael@0:     uint64_t byteCount;
michael@0: 
michael@0:     // state (ABCDE)
michael@0:     uint32_t state[5];
michael@0: 
michael@0:     // input buffer
michael@0:     uint8_t buffer[64];
michael@0: };
michael@0: 
michael@0: #endif