nuttx/libs/libc/string/lib_strlen.c
Tiago Medicci Serrano 58e97e521c libc/string: prevent libc in the kernel/userspace optionally
Add the `LIBC_PREVENT_STRING_KERNEL` and `LIBC_PREVENT_STRING_USER`
that are meant to be selected by the chip if no libc implementation
is going to be built. If selected, neither NuttX's software version
of the libc nor any architecture-specific implementation will be
built in the kernel or in the userspace, respectively. In this
case, the linker may provide a ROM-defined version of the libc
functions instead.
2023-05-17 13:58:48 +08:00

44 lines
1.6 KiB
C

/****************************************************************************
* libs/libc/string/lib_strlen.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <string.h>
#include "libc.h"
/****************************************************************************
* Public Functions
****************************************************************************/
#if !defined(CONFIG_LIBC_ARCH_STRLEN) && defined(LIBC_BUILD_STRING)
#undef strlen /* See mm/README.txt */
size_t strlen(const char *s)
{
const char *sc;
for (sc = s; *sc != '\0'; ++sc);
return sc - s;
}
#endif