incubator-nuttx/libs/libc/stdio/lib_tmpnam.c

81 lines
3.1 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_tmpnam.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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 <stdio.h>
#include <stdlib.h>
#include <errno.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tmpnam
*
* Description:
* The tmpnam() function generates a string that is a valid filename and
* that is not the same as the name of an existing file. The function is
* potentially capable of generating TMP_MAX different strings, but any or
* all of them may already be in use by existing files and thus not be
* suitable return values.
*
* The tmpnam() function generates a different string each time it is
* called from the same process, up to {TMP_MAX} times. If it is called
* more than {TMP_MAX} times, the behavior is implementation-defined.
*
* Returned Value:
* Upon successful completion, tmpnam() returns a pointer to a string. I
* no suitable string can be generated, the tmpnam() function will
* return a null pointer.
*
* If the argument s is a null pointer, tmpnam() will leave its result
* in an internal static object and return a pointer to that object.
* Subsequent calls to tmpnam() may modify the same object. If the
* argument s is not a null pointer, it is presumed to point to an
* array of at least L_tmpnam chars; tmpnam() will write its result in
* that array and will return the argument as its value.
*
****************************************************************************/
FAR char *tmpnam(FAR char *s)
{
static char path[L_tmpnam];
if (s == NULL)
{
s = path;
}
snprintf(s, L_tmpnam, "%s/XXXXXX", P_tmpdir);
return mktemp(s);
}