Coverage Report

Created: 2021-02-21 07:20

/src/botan/src/lib/hash/checksum/adler32/adler32.cpp
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Source (jump to first uncovered line)
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/*
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* Adler32
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* (C) 1999-2007 Jack Lloyd
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*
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* Botan is released under the Simplified BSD License (see license.txt)
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*/
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#include <botan/internal/adler32.h>
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#include <botan/internal/loadstor.h>
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namespace Botan {
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namespace {
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void adler32_update(const uint8_t input[], size_t length,
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                    uint16_t& S1, uint16_t& S2)
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   {
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   uint32_t S1x = S1;
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   uint32_t S2x = S2;
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   while(length >= 16)
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      {
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      S1x += input[ 0]; S2x += S1x;
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      S1x += input[ 1]; S2x += S1x;
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      S1x += input[ 2]; S2x += S1x;
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      S1x += input[ 3]; S2x += S1x;
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      S1x += input[ 4]; S2x += S1x;
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      S1x += input[ 5]; S2x += S1x;
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      S1x += input[ 6]; S2x += S1x;
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      S1x += input[ 7]; S2x += S1x;
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      S1x += input[ 8]; S2x += S1x;
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      S1x += input[ 9]; S2x += S1x;
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      S1x += input[10]; S2x += S1x;
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      S1x += input[11]; S2x += S1x;
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      S1x += input[12]; S2x += S1x;
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      S1x += input[13]; S2x += S1x;
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      S1x += input[14]; S2x += S1x;
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      S1x += input[15]; S2x += S1x;
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      input += 16;
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      length -= 16;
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      }
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   for(size_t j = 0; j != length; ++j)
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      {
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      S1x += input[j];
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      S2x += S1x;
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      }
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   S1 = S1x % 65521;
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   S2 = S2x % 65521;
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   }
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}
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/*
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* Update an Adler32 Checksum
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*/
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void Adler32::add_data(const uint8_t input[], size_t length)
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   {
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   const size_t PROCESS_AMOUNT = 5552;
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   while(length >= PROCESS_AMOUNT)
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      {
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      adler32_update(input, PROCESS_AMOUNT, m_S1, m_S2);
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      input += PROCESS_AMOUNT;
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      length -= PROCESS_AMOUNT;
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      }
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   adler32_update(input, length, m_S1, m_S2);
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   }
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/*
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* Finalize an Adler32 Checksum
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*/
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void Adler32::final_result(uint8_t output[])
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   {
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   store_be(output, m_S2, m_S1);
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   clear();
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   }
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std::unique_ptr<HashFunction> Adler32::copy_state() const
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   {
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   return std::unique_ptr<HashFunction>(new Adler32(*this));
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   }
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}