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/*
* Copyright 1996-2002 - Karl R. Hakimian and David Fries
*
* This file is part of datalink.
*
* Datalink 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.
*
* Datalink 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 datalink (see COPYING); if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
/*
* Linux version of Timex/Microsoft SDK for Timex datalink watches.
* SVGA needs a terminal when going to graphics mode. This will take
* care of that.
*/
#include <unistd.h>
#include <stdio.h>
#include <sys/vt.h>
#include <sys/ioctl.h>
#include <sys/fcntl.h>
#define VTFMT "/dev/tty%d"
int open_vt()
{
struct vt_stat vts;
int fd;
int newvt;
char buf[1024];
/* Need to become root again to deal with vt's */
seteuid(0);
if ((fd = open("/dev/tty", O_RDWR)) == -1)
{
perror("open");
return (-1);
}
/* See if we are on a VT. */
if (ioctl(fd, VT_GETSTATE, &vts) == 0)
{
close(fd);
return (0);
}
/* We are not on a VT, switch to one. */
close(fd);
if ((fd = open("/dev/tty0", O_RDWR)) == -1)
{
perror("open");
return (-1);
}
/* Get info on current vt. */
if (ioctl(fd, VT_GETSTATE, &vts) == -1)
{
perror("VT_GETSTATE");
return (-1);
}
/* Open a new vt. */
if (ioctl(fd, VT_OPENQRY, &newvt) == -1)
{
perror("VT_OPENQRY");
return (-1);
}
if (newvt == -1)
{
fprintf(stderr, "No free vts to open\n");
return (-1);
}
/* Make the new vt, the active vt. */
if (ioctl(fd, VT_ACTIVATE, newvt) == -1)
{
perror("VT_ACTIVATE");
return (-1);
}
if (ioctl(fd, VT_WAITACTIVE, newvt) == -1)
{
perror("VT_WAITACTIVE");
return (-1);
}
close(fd);
close(2);
close(1);
close(0);
/*
Detach from controlling terminal here so that we can get a new
controlling terminal.
*/
setsid();
sprintf(buf, VTFMT, newvt);
(void) open(buf, O_RDWR);
(void) open(buf, O_RDWR);
(void) open(buf, O_RDWR);
/* No longer need root privs - drop them*/
seteuid(getuid());
return (vts.v_active);
}
void close_vt(int oldvt)
{
int fd;
struct vt_stat vts;
struct vt_mode VT;
int vt;
if (!oldvt)
return;
/* Need to become root again to deal with vt's */
seteuid(0);
/* SVGA lib sets the tty change mode to require a call back.
* We aren't in graphics mode, so set it back to auto.
*/
if( ioctl(0, VT_GETMODE, &VT) == -1)
{
perror("VT_GETMODE");
return;
}
VT.mode = VT_AUTO;
if( ioctl(0, VT_SETMODE, &VT)== -1)
{
perror("VT_SETMODE");
return;
}
/* Get info on current vt. */
if (ioctl(0, VT_GETSTATE, &vts) == -1)
{
perror("VT_GETSTATE");
return;
}
vt = vts.v_active;
/* Switch back to previous vt. */
if (ioctl(0, VT_ACTIVATE, oldvt) == -1)
{
perror("VT_ACTIVATE");
return;
}
if (ioctl(0, VT_WAITACTIVE, oldvt) == -1)
{
perror("VT_WAITACTIVE");
return;
}
close(0);
close(1);
close(2);
setsid();
/* Open current vt. */
if ((fd = open("/dev/tty0", O_RDWR)) == -1)
{
perror("open");
return;
}
/* Free up our old vt. */
if (ioctl(fd, VT_DISALLOCATE, vt) == -1)
{
perror("VT_DISALLOCATE");
return;
}
close(fd);
/* No longer need root privs - drop them*/
seteuid(getuid());
}
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