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/*
*
* BlueZ - Bluetooth protocol stack for Linux
*
* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
* Copyright (C) 2002-2009 Marcel Holtmann <marcel@holtmann.org>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdint.h>
#include <stdlib.h>
#include <syslog.h>
#include <setjmp.h>
#include <string.h>
#include "lib.h"
#include "dund.h"
#define MS_PPP 2
#define MS_SUCCESS 1
#define MS_FAILED -1
#define MS_TIMEOUT -2
static sigjmp_buf jmp;
static int retry;
static int timeout;
static void sig_alarm(int sig)
{
siglongjmp(jmp, MS_TIMEOUT);
}
static int w4_str(int fd, char *str)
{
char buf[40];
unsigned len = 0;
int r;
while (1) {
r = read(fd, buf + len, sizeof(buf) - len - 1);
if (r < 0) {
if (errno == EINTR || errno == EAGAIN)
continue;
break;
}
if (!r)
break;
len += r;
if (len < strlen(str))
continue;
buf[len] = 0;
if (strstr(buf, str))
return MS_SUCCESS;
/* Detect PPP */
if (strchr(buf, '~'))
return MS_PPP;
}
return MS_FAILED;
}
static int ms_server(int fd)
{
switch (w4_str(fd, "CLIENT")) {
case MS_SUCCESS:
write_n(fd, "CLIENTSERVER", 12);
case MS_PPP:
return MS_SUCCESS;
default:
return MS_FAILED;
}
}
static int ms_client(int fd)
{
write_n(fd, "CLIENT", 6);
return w4_str(fd, "CLIENTSERVER");
}
int ms_dun(int fd, int server, int timeo)
{
sig_t osig;
retry = 4;
timeout = timeo;
if (!server)
timeout /= retry;
osig = signal(SIGALRM, sig_alarm);
while (1) {
int r = sigsetjmp(jmp, 1);
if (r) {
if (r == MS_TIMEOUT && !server && --retry)
continue;
alarm(0);
signal(SIGALRM, osig);
switch (r) {
case MS_SUCCESS:
case MS_PPP:
errno = 0;
return 0;
case MS_FAILED:
errno = EPROTO;
break;
case MS_TIMEOUT:
errno = ETIMEDOUT;
break;
}
return -1;
}
alarm(timeout);
if (server)
r = ms_server(fd);
else
r = ms_client(fd);
siglongjmp(jmp, r);
}
}
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