44 lines
953 B
C
44 lines
953 B
C
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/*
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* memmove.c: memmove compat implementation.
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*
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* Copyright (c) 2001-2008, NLnet Labs. All rights reserved.
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*
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* See LICENSE for the license.
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*/
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#include <ldns/config.h>
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#include <stdlib.h>
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void *memmove(void *dest, const void *src, size_t n);
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void *memmove(void *dest, const void *src, size_t n)
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{
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uint8_t* from = (uint8_t*) src;
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uint8_t* to = (uint8_t*) dest;
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if (from == to || n == 0)
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return dest;
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if (to > from && to-from < (int)n) {
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/* to overlaps with from */
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/* <from......> */
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/* <to........> */
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/* copy in reverse, to avoid overwriting from */
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int i;
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for(i=n-1; i>=0; i--)
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to[i] = from[i];
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return dest;
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}
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if (from > to && from-to < (int)n) {
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/* to overlaps with from */
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/* <from......> */
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/* <to........> */
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/* copy forwards, to avoid overwriting from */
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size_t i;
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for(i=0; i<n; i++)
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to[i] = from[i];
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return dest;
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}
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memcpy(dest, src, n);
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return dest;
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}
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