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https://github.com/aaru-dps/Aaru.Checksums.Native.git
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65 lines
1.7 KiB
C
65 lines
1.7 KiB
C
/*
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* This file is part of the Aaru Data Preservation Suite.
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* Copyright (c) 2019-2021 Natalia Portillo.
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*
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* This library is free software; you can redistribute it and/or modify
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* it under the terms of the GNU Lesser General Public License as
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* published by the Free Software Foundation; either version 2.1 of the
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* License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <stdint.h>
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#include <stdlib.h>
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#include "library.h"
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#include "fletcher32.h"
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AARU_EXPORT fletcher32_ctx* AARU_CALL fletcher32_init()
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{
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fletcher32_ctx* ctx;
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ctx = (fletcher32_ctx*)malloc(sizeof(fletcher32_ctx));
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if(!ctx) return NULL;
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ctx->sum1 = 0xFFFF;
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ctx->sum2 = 0xFFFF;
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return ctx;
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}
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AARU_EXPORT int AARU_CALL fletcher32_update(fletcher32_ctx* ctx, const uint8_t* data, uint32_t len)
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{
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if(!ctx || !data) return -1;
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for(uint32_t i = 0; i < len; i++)
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{
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ctx->sum1 = (ctx->sum1 + data[i]) % FLETCHER32_MODULE;
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ctx->sum2 = (ctx->sum2 + ctx->sum1) % FLETCHER32_MODULE;
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}
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return 0;
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}
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AARU_EXPORT int AARU_CALL fletcher32_final(fletcher32_ctx* ctx, uint32_t* checksum)
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{
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if(!ctx) return -1;
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*checksum = (ctx->sum2 << 16) | ctx->sum1;
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return 0;
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}
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AARU_EXPORT void AARU_CALL fletcher32_free(fletcher32_ctx* ctx)
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{
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if(!ctx) return;
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free(ctx);
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} |