nuttx/libs/libc/string/lib_bsdstpcpy.c
anjiahao bd6b226546 libs/libc/string: Use long long to speed up the BSD string functions.
Most hardware accesses the memory through a 64-bit bus, so handle the
data in 64-bit chunks instead of "long" chunks which are only 32-bit
wide on the 32-bit platforms.

* Add the libc_data_t type (unsigned long long) and move the shared
  UNALIGNED/UNALIGNED_X/ALIGNED, LITTLEBLOCKSIZE, TOO_SMALL and
  DETECTNULL helpers from the individual C files to libs/libc/libc.h.
* Convert all lib_bsd*.c implementations to the new type and macros,
  which also drops the duplicated LONG_MAX conditionals.

Assisted-by: Claude:claude-opus-5
Signed-off-by: anjiahao <anjiahao@xiaomi.com>
2026-08-17 10:47:33 +02:00

86 lines
2.8 KiB
C

/****************************************************************************
* libs/libc/string/lib_bsdstpcpy.c
*
* SPDX-License-Identifier: BSD
* SPDX-FileCopyrightText: 1994-2009 Red Hat, Inc. All rights reserved
*
* 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>
#include "libc.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* 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
no_builtin("stpcpy")
nosanitize_address
FAR char *stpcpy(FAR char *dest, FAR const char *src)
{
FAR libc_data_t *aligned_dst;
FAR const libc_data_t *aligned_src;
/* If src or dest is unaligned, then copy bytes. */
if (!UNALIGNED(src, dest))
{
aligned_dst = (FAR libc_data_t *)dest;
aligned_src = (FAR libc_data_t *)src;
/* src and dest are both "libc_data_t" aligned, try to do "libc_data_t"
* 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