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/*
* Copyright © 2016 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
*/
#include <errno.h>
#include <stdlib.h>
#include <unistd.h>
#include "igt_io.h"
/**
* SECTION:igt_io
* @short_description: Helpers for file I/O
* @title: io
* @include: igt_io.h
*
* This library provides helpers for file I/O
*/
/**
* igt_readn:
* @fd: the file descriptor
* @buf: buffer where the contents will be stored, allocated by the caller
* @size: size of the buffer
*
* Read from fd into provided buffer until the buffer is full or EOF
*
* Returns:
* -errno on failure or bytes read on success
*/
ssize_t igt_readn(int fd, char *buf, size_t len)
{
ssize_t ret;
size_t total = 0;
do {
ret = read(fd, buf + total, len - total);
if (ret < 0)
ret = -errno;
if (ret == -EINTR || ret == -EAGAIN)
continue;
if (ret <= 0)
break;
total += ret;
} while (total != len);
return total ?: ret;
}
/**
* igt_writen:
* @fd: the file descriptor
* @buf: the block with the contents to write
* @len: the length to write
*
* This writes @len bytes from @data to the sysfs file.
*
* Returns:
* -errno on failure or bytes written on success
*/
ssize_t igt_writen(int fd, const char *buf, size_t len)
{
ssize_t ret;
size_t total = 0;
do {
ret = write(fd, buf + total, len - total);
if (ret < 0)
ret = -errno;
if (ret == -EINTR || ret == -EAGAIN)
continue;
if (ret <= 0)
break;
total += ret;
} while (total != len);
return total ?: ret;
}
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