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/* $OpenBSD: atomicio.c,v 1.1 2008/11/26 06:51:43 uwe Exp $ */
/*
* Copyright (c) 2003 Can Erkin Acar
* Copyright (c) 2003 Anil Madhavapeddy <anil@recoil.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <errno.h>
#include <unistd.h>
#include "btd.h"
/* Read data with the assertion that it all must come through, or
* else abort the process. Based on atomicio() from openssh. */
int
atomic_read(int fd, void *buf, size_t n)
{
char *s = buf;
ssize_t res, pos = 0;
while (n > pos) {
res = read(fd, s + pos, n - pos);
switch (res) {
case -1:
if (errno == EINTR || errno == EAGAIN)
continue;
return -1;
case 0:
errno = 0;
return -1;
default:
pos += res;
}
}
return 0;
}
/* Write data with the assertion that it all has to be written, or
* else abort the process. Based on atomicio() from openssh. */
int
atomic_write(int fd, const void *buf, size_t n)
{
const char *s = buf;
ssize_t res, pos = 0;
while (n > pos) {
res = write(fd, s + pos, n - pos);
switch (res) {
case -1:
if (errno == EINTR || errno == EAGAIN)
continue;
return -1;
case 0:
errno = 0;
return -1;
default:
pos += res;
}
}
return 0;
}
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