incubator-nuttx/libs/libc/string/lib_bsdstpcpy.c

96 lines
3.1 KiB
C

/****************************************************************************
* libs/libc/string/lib_bsdstpcpy.c
*
* Copyright (c) 1994-2009 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the BSD License. This program is distributed in the hope that
* it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
* including the implied warranties of MERCHANTABILITY or FITNESS FOR
* A PARTICULAR PURPOSE. A copy of this license is available at
* http://www.opensource.org/licenses. Any Red Hat trademarks that are
* incorporated in the source code or documentation are not subject to
* the BSD License and may only be used or replicated with the express
* permission of Red Hat, Inc.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Nonzero if either x or y is not aligned on a "long" boundary. */
#define UNALIGNED(x, y) \
(((long)(uintptr_t)(x) & (sizeof(long) - 1)) | ((long)(uintptr_t)(y) & (sizeof(long) - 1)))
/* Macros for detecting endchar */
#if LONG_MAX == 2147483647
# define DETECTNULL(x) (((x) - 0x01010101) & ~(x) & 0x80808080)
#elif LONG_MAX == 9223372036854775807
/* Nonzero if x (a long int) contains a NULL byte. */
# define DETECTNULL(x) (((x) - 0x0101010101010101) & ~(x) & 0x8080808080808080)
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stpcpy
*
* Description:
* Copies the string pointed to by 'src' (including the terminating NUL
* character) into the array pointed to by 'dest'.
*
* Returned Value:
* The stpcpy() function returns a pointer to the terminating NUL
* character copied into the 'dest' buffer
*
****************************************************************************/
#ifndef CONFIG_LIBC_ARCH_STPCPY
#undef stpcpy /* See mm/README.txt */
nosanitize_address
FAR char *stpcpy(FAR char *dest, FAR const char *src)
{
FAR long *aligned_dst;
FAR const long *aligned_src;
/* If src or dest is unaligned, then copy bytes. */
if (!UNALIGNED(src, dest))
{
aligned_dst = (FAR long *)dest;
aligned_src = (FAR long *)src;
/* src and dest are both "long int" aligned, try to do "long int"
* sized copies.
*/
while (!DETECTNULL(*aligned_src))
{
*aligned_dst++ = *aligned_src++;
}
dest = (FAR char *)aligned_dst;
src = (FAR char *)aligned_src;
}
while ((*dest++ = *src++) != '\0');
return --dest;
}
#endif