newlib/winsup/cygwin/tty.cc

285 lines
5.3 KiB
C++

/* tty.cc
Copyright 1997, 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009,
2010, 2011, 2012, 2013, 2015 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include "miscfuncs.h"
#include <unistd.h>
#include <utmp.h>
#include <sys/cygwin.h>
#include "cygerrno.h"
#include "security.h"
#include "path.h"
#include "fhandler.h"
#include "dtable.h"
#include "cygheap.h"
#include "pinfo.h"
#include "shared_info.h"
HANDLE NO_COPY tty_list::mutex = NULL;
extern "C" int
getpt (void)
{
return open ("/dev/ptmx", O_RDWR | O_NOCTTY);
}
extern "C" int
posix_openpt (int oflags)
{
return open ("/dev/ptmx", oflags);
}
extern "C" int
grantpt (int fd)
{
cygheap_fdget cfd (fd);
return cfd < 0 ? -1 : 0;
}
extern "C" int
unlockpt (int fd)
{
cygheap_fdget cfd (fd);
return cfd < 0 ? -1 : 0;
}
extern "C" int
revoke (char *ttyname)
{
set_errno (ENOSYS);
return -1;
}
extern "C" int
ttyslot (void)
{
if (myself->ctty <= 0 || iscons_dev (myself->ctty))
return -1;
return device::minor (myself->ctty);
}
void __stdcall
tty_list::init_session ()
{
char mutex_name[MAX_PATH];
char *name = shared_name (mutex_name, "tty_list::mutex", 0);
/* tty_list::mutex is used while searching for a tty slot */
if (!(mutex = CreateMutex (&sec_all_nih, FALSE, name)))
api_fatal ("can't create tty_list::mutex '%s', %E", name);
ProtectHandle (mutex);
}
void __stdcall
tty::init_session ()
{
if (!myself->cygstarted && NOTSTATE (myself, PID_CYGPARENT))
cygheap->fdtab.get_debugger_info ();
}
int __reg2
tty_list::attach (int n)
{
int res;
if (iscons_dev (n))
res = -1;
else if (n != -1)
res = connect (device::minor (n));
else
res = -1;
return res;
}
int
tty_list::connect (int ttynum)
{
if (ttynum < 0 || ttynum >= NTTYS)
{
termios_printf ("ttynum (%d) out of range", ttynum);
return -1;
}
if (!ttys[ttynum].exists ())
{
termios_printf ("pty %d was not allocated", ttynum);
set_errno (ENXIO);
return -1;
}
return ttynum;
}
void
tty_list::init ()
{
for (int i = 0; i < NTTYS; i++)
{
ttys[i].init ();
ttys[i].setntty (DEV_PTYS_MAJOR, i);
}
}
/* Search for a free tty and allocate it.
Return tty number or -1 if error.
*/
int
tty_list::allocate (HANDLE& r, HANDLE& w)
{
lock_ttys here;
int freetty = -1;
tty *t = NULL;
for (int i = 0; i < NTTYS; i++)
if (ttys[i].not_allocated (r, w))
{
t = ttys + i;
t->init ();
t->setsid (0);
freetty = i;
break;
}
if (freetty >= 0)
termios_printf ("pty%d allocated", freetty);
else
{
system_printf ("No pty allocated");
r = w = NULL;
}
return freetty;
}
bool
tty::not_allocated (HANDLE& r, HANDLE& w)
{
/* Attempt to open the from-master side of the tty. If it is accessible
then it exists although we may not have privileges to actually use it. */
char pipename[sizeof("ptyNNNN-from-master")];
__small_sprintf (pipename, "pty%d-from-master", get_minor ());
/* fhandler_pipe::create returns 0 when creation succeeds */
return fhandler_pipe::create (&sec_none, &r, &w,
fhandler_pty_common::pipesize, pipename,
0) == 0;
}
bool
tty::exists ()
{
HANDLE r, w;
bool res;
if (!not_allocated (r, w))
res = true;
else
{
/* Handles are left open when not_allocated finds a non-open "tty" */
CloseHandle (r);
CloseHandle (w);
res = false;
}
debug_printf ("exists %d", res);
return res;
}
bool
tty::slave_alive ()
{
HANDLE ev;
if ((ev = open_inuse (READ_CONTROL)))
CloseHandle (ev);
return ev != NULL;
}
HANDLE
tty::open_mutex (const char *mutex, ACCESS_MASK access)
{
char buf[MAX_PATH];
shared_name (buf, mutex, get_minor ());
return OpenMutex (access, TRUE, buf);
}
HANDLE
tty::open_inuse (ACCESS_MASK access)
{
char buf[MAX_PATH];
shared_name (buf, TTY_SLAVE_ALIVE, get_minor ());
return OpenEvent (access, FALSE, buf);
}
HANDLE
tty::create_inuse (PSECURITY_ATTRIBUTES sa)
{
HANDLE h;
char buf[MAX_PATH];
shared_name (buf, TTY_SLAVE_ALIVE, get_minor ());
h = CreateEvent (sa, TRUE, FALSE, buf);
termios_printf ("%s %p", buf, h);
if (!h)
termios_printf ("couldn't open inuse event %s, %E", buf);
return h;
}
void
tty::init ()
{
output_stopped = 0;
setsid (0);
pgid = 0;
was_opened = false;
master_pid = 0;
is_console = false;
column = 0;
}
HANDLE
tty::get_event (const char *fmt, PSECURITY_ATTRIBUTES sa, BOOL manual_reset)
{
HANDLE hev;
char buf[MAX_PATH];
shared_name (buf, fmt, get_minor ());
if (!sa)
sa = &sec_all;
if (!(hev = CreateEvent (sa, manual_reset, FALSE, buf)))
{
termios_printf ("couldn't create %s", buf);
set_errno (ENOENT); /* FIXME this can't be the right errno */
return NULL;
}
termios_printf ("created event %s", buf);
return hev;
}
lock_ttys::lock_ttys (DWORD howlong): release_me (true)
{
if (WaitForSingleObject (tty_list::mutex, howlong) == WAIT_FAILED)
{
termios_printf ("WFSO for mutex %p failed, %E", tty_list::mutex);
release_me = false;
}
}
void
lock_ttys::release ()
{
ReleaseMutex (tty_list::mutex);
}
const char *
tty_min::ttyname ()
{
device d;
d.parse (ntty);
return d.name;
}