platform_bionic/libc/unistd/eventfd.c
Elliott Hughes 387d4b7de9 Auto-generate a complete NOTICE file.
Remove the hand-collated ones, and switch to a script that pulls the
copyright headers out of every file and collects the unique ones.

Change-Id: Ied3b98b3f56241df97166c410ff81de4e0157c9d
2012-08-09 16:05:31 -07:00

53 lines
1.9 KiB
C

/*
* Copyright (C) 2010 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
*
* 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.
*/
#include <sys/eventfd.h>
#include <unistd.h>
/* We duplicate the GLibc error semantics, which are poorly defined
* if the read() or write() does not return the proper number of bytes.
*/
int eventfd_read(int fd, eventfd_t *counter)
{
int ret = read(fd, counter, sizeof(*counter));
if (ret == sizeof(*counter))
return 0;
return -1;
}
int eventfd_write(int fd, eventfd_t counter)
{
int ret = write(fd, &counter, sizeof(counter));
if (ret == sizeof(counter))
return 0;
return -1;
}