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Viewing changes to boot/generic/src/memstr.c

  • Committer: Jakub Jermar
  • Date: 2012-03-29 21:41:07 UTC
  • Revision ID: jakub@jermar.eu-20120329214107-3sgmwls8rr10y1q2
Add memmove() to boot.

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boot/generic/src/memstr.c
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        return dst;
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}
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/** Move memory block with possible overlapping.
 
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 *
 
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 * Copy cnt bytes from src address to dst address. The source
 
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 * and destination memory areas may overlap.
 
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 *
 
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 * @param dst Destination address to copy to.
 
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 * @param src Source address to copy from.
 
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 * @param cnt Number of bytes to copy.
 
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 *
 
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 * @return Destination address.
 
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 *
 
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 */
 
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void *memmove(void *dst, const void *src, size_t cnt)
 
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{
 
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        /* Nothing to do? */
 
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        if (src == dst)
 
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                return dst;
 
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        /* Non-overlapping? */
 
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        if ((dst >= src + cnt) || (src >= dst + cnt))
 
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                return memcpy(dst, src, cnt);
 
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        uint8_t *dp;
 
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        const uint8_t *sp;
 
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        /* Which direction? */
 
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        if (src > dst) {
 
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                /* Forwards. */
 
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                dp = dst;
 
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                sp = src;
 
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                while (cnt-- != 0)
 
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                        *dp++ = *sp++;
 
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        } else {
 
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                /* Backwards. */
 
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                dp = dst + (cnt - 1);
 
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                sp = src + (cnt - 1);
 
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                while (cnt-- != 0)
 
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                        *dp-- = *sp--;
 
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        }
 
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        return dst;
 
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}
 
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/** @}
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 */