incubator-nuttx/libc/stdio/lib_gets_s.c

97 lines
4.0 KiB
C

/****************************************************************************
* libc/stdio/lib_gets_s.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdio.h>
#include <stdint.h>
#include "lib_internal.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: gets
*
* Description:
* gets() reads a line from stdin into the buffer pointed to by s until
* either a terminating newline or EOF, which it replaces with '\0'. Reads
* at most n-1 characters from stdin into the array pointed to by str until
* new-line character, end-of-file condition, or read error. The newline
* character, if encountered, is not saved in the arraay. A NUL character
* is written immediately after the last character read into the array, or
* to str[0] if no characters were read.
*
* If n is zero or is greater than RSIZE_MAX, a null character is written
* to str[0] but the function reads and discards characters from stdin
* until new-line character, end-of-file condition, or read error (not
* implemented).
*
* If n-1 characters have been read, continues reading and discarding the
* characters from stdin until new-line character, end-of-file condition,
* or read error.
*
**************************************************************************/
FAR char *gets_s(FAR char *s, rsize_t n)
{
/* Handle the case where n is out of range as required */
if (n < 1 || n > RSIZE_MAX)
{
/* Set n=1, i.e., room only for the NUL terminator */
n = 1;
}
/* Then let lib_fgets() do the heavy lifting */
return lib_fgets(s, (size_t)n, stdin, false, true);
}