86 lines
1.3 KiB
C
86 lines
1.3 KiB
C
/*++
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Copyright (c) 2024, Quinn Stephens.
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Provided under the BSD 3-Clause license.
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Module Name:
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mem.c
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Abstract:
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Provides memory manipulation routines.
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--*/
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#include <string.h>
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void *
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memset (
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void *dest,
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int c,
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size_t count
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)
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{
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void *ptr = dest;
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while (count--) {
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*(char *)dest = (char)c;
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dest = (char *)dest + 1;
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}
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return ptr;
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}
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void *
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memcpy (
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void *dest,
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const void *src,
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size_t count
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)
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{
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void *ptr = dest;
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while (count--) {
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*(char *)dest = *(char *)src;
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dest = (char *)dest + 1;
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src = (char *)src + 1;
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}
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return ptr;
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}
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void *
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memmove (
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void *dest,
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const void *src,
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size_t count
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)
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{
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void *ptr = dest;
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/* Check for overlap */
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if (src > dest || ((char *)src + count) < (char *)dest) {
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/* Low-to-high copy, like memcpy() */
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while (count--) {
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*(char *)dest = *(char *)src;
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dest = (char *)dest + 1;
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src = (char *)src + 1;
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}
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} else {
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/* High-to-low copy */
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dest = (char *)dest + count - 1;
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src = (char *)src + count - 1;
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while (count--) {
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*(char *)dest = *(char *)src;
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dest = (char *)dest - 1;
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src = (char *)src - 1;
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}
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}
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return ptr;
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}
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