opencv

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/* crc32_fold.c -- crc32 folding interface
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 * Copyright (C) 2021 Nathan Moinvaziri
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 * For conditions of distribution and use, see copyright notice in zlib.h
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 */
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#include "zbuild.h"
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#include "functable.h"
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#include "crc32_fold.h"
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#include <limits.h>
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Z_INTERNAL uint32_t crc32_fold_reset_c(crc32_fold *crc) {
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    crc->value = CRC32_INITIAL_VALUE;
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    return crc->value;
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}
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Z_INTERNAL void crc32_fold_copy_c(crc32_fold *crc, uint8_t *dst, const uint8_t *src, size_t len) {
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    crc->value = functable.crc32(crc->value, src, len);
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    memcpy(dst, src, len);
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}
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Z_INTERNAL void crc32_fold_c(crc32_fold *crc, const uint8_t *src, size_t len, uint32_t init_crc) {
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    /* Note: while this is basically the same thing as the vanilla CRC function, we still need
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     * a functable entry for it so that we can generically dispatch to this function with the
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     * same arguments for the versions that _do_ do a folding CRC but we don't want a copy. The
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     * init_crc is an unused argument in this context */
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    Z_UNUSED(init_crc);
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    crc->value = functable.crc32(crc->value, src, len);
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}
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Z_INTERNAL uint32_t crc32_fold_final_c(crc32_fold *crc) {
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    return crc->value;
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}
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