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/*
 * Copyright (c) 1995, 1996, 1997, 1998 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * All rights reserved.
 *
 * 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 of the Institute 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 INSTITUTE 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 INSTITUTE 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/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include "net_read_write.h"

/*
 * Like read but never return partial data.
 */

ssize_t
net_read (int fd, void *buf, size_t nbytes)
{
    char *cbuf = (char *)buf;
    ssize_t count;
    size_t rem = nbytes;

    while (rem > 0) {
	count = read (fd, cbuf, rem);
	if (count < 0) {
	    if (errno == EINTR)
		continue;
	    else
		return count;
	} else if (count == 0) {
	    return count;
	}
	cbuf += (size_t) count;
	rem -= (size_t) count;
    }
    return (ssize_t)nbytes;
}

/*
 * Like write but never return partial data.
 */

ssize_t
net_write (int fd, const void *buf, size_t nbytes)
{
    const char *cbuf = (const char *)buf;
    ssize_t count;
    size_t rem = nbytes;

    while (rem > 0) {
	count = write (fd, cbuf, rem);
	if (count < 0) {
	    if (errno == EINTR)
		continue;
	    else
		return count;
	}
	cbuf += (size_t)count;
	rem -= (size_t)count;
    }
    return (ssize_t)nbytes;
}