nuttx/libs/libc/stdio/lib_vfprintf.c
Miguel Herranz 819ebe7356 libc/stdio: Add stdio file locking functions
Add flockfile(), ftrylockfile() and funlockfile() functions [1].

[1] POSIX.1-2008 / System Interfaces / flockfile
    https://pubs.opengroup.org/onlinepubs/9699919799.2008edition/functions/flockfile.html

Signed-off-by: Miguel Herranz <miguel@midokura.com>
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
2022-10-22 23:34:45 +08:00

57 lines
1.9 KiB
C

/****************************************************************************
* libs/libc/stdio/lib_vfprintf.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 <stdio.h>
#include "libc.h"
/****************************************************************************
* Public Functions
****************************************************************************/
int vfprintf(FAR FILE *stream, FAR const IPTR char *fmt, va_list ap)
{
struct lib_stdoutstream_s stdoutstream;
int n = ERROR;
/* Wrap the stream in a stream object and let lib_vsprintf
* do the work.
*/
lib_stdoutstream(&stdoutstream, stream);
/* Hold the stream semaphore throughout the lib_vsprintf
* call so that this thread can get its entire message out
* before being pre-empted by the next thread.
*/
flockfile(stream);
n = lib_vsprintf(&stdoutstream.public, fmt, ap);
funlockfile(stream);
return n;
}