Create gdb_termios.h (and cleanup gdb/{,gdbserver/}terminal.h)

As requested, I'm sending this as a separate patch because it is ready
to be included as-is.

The idea here is that both gdb/terminal.h and gdb/gdbserver/terminal.h
share the same code, which is responsible for setting a bunch of
defines on based on the presence of termios.h and a few other headers.
This simple patch just moves this common code to common/gdb_termios.h
and makes the necessary adjustments on both GDB and gdbserver so that
they can use this new header.  It also implements the some header
checks on common/common.m4.

As a bonus, gdb/gdbserver/terminal.h can be removed because it's now
empty.

Built on x86_64, no regressions found.

gdb/ChangeLog:
2017-04-12  Sergio Durigan Junior  <sergiodj@redhat.com>

	* Makefile.in (HFILES_NO_SRCDIR): Add "common/gdb_termios.h".
	* common/common.m4: Check headers 'termios.h', 'termio.h' and
	'sgtty.h'.
	* common/gdb_termios.h: New file, with parts of "terminal.h".
	* inflow.c: Include "gdb_termios.h".
	* ser-unix.c: Include "gdb_termios.h".
	* terminal.h: Move terminal-related defines to
	"common/gdb_termios.h".

gdb/gdbserver/ChangeLog:
2017-04-12  Sergio Durigan Junior  <sergiodj@redhat.com>

	* remote-utils.c: Include "gdb_termios.h" instead of
	"terminal.h".
	* terminal.h: Delete file.

3 files changed, 7 insertions, 52 deletions

diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 1f8c593..2060d25 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,5 +1,11 @@
 2017-04-12  Sergio Durigan Junior  <sergiodj@redhat.com>
 
+	* remote-utils.c: Include "gdb_termios.h" instead of
+	"terminal.h".
+	* terminal.h: Delete file.
+
+2017-04-12  Sergio Durigan Junior  <sergiodj@redhat.com>
+
 	* server.c: Include <vector>.
 	<program_argv, wrapper_argv>: Convert to std::vector.
 	(start_inferior): Rewrite function to use C++.
diff --git a/gdb/gdbserver/remote-utils.c b/gdb/gdbserver/remote-utils.c
index 37a6402..25b7e41 100644
--- a/gdb/gdbserver/remote-utils.c
+++ b/gdb/gdbserver/remote-utils.c
@@ -17,7 +17,7 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "server.h"
-#include "terminal.h"
+#include "gdb_termios.h"
 #include "target.h"
 #include "gdbthread.h"
 #include "tdesc.h"
diff --git a/gdb/gdbserver/terminal.h b/gdb/gdbserver/terminal.h
deleted file mode 100644
index 3bdd5f5..0000000
--- a/gdb/gdbserver/terminal.h
+++ /dev/null
@@ -1,51 +0,0 @@
-/* Terminal interface definitions for the GDB remote server.
-   Copyright (C) 2002-2017 Free Software Foundation, Inc.
-
-   This file is part of GDB.
-
-   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 3 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, see <http://www.gnu.org/licenses/>.  */
-
-#if !defined (TERMINAL_H)
-#define TERMINAL_H 1
-
-/* Autoconf will have defined HAVE_TERMIOS_H, HAVE_TERMIO_H,
-   and HAVE_SGTTY_H for us as appropriate.  */
-
-#if defined(HAVE_TERMIOS_H)
-#define HAVE_TERMIOS
-#include <termios.h>
-#else /* ! HAVE_TERMIOS_H */
-#if defined(HAVE_TERMIO_H)
-#define HAVE_TERMIO
-#include <termio.h>
-
-#undef TIOCGETP
-#define TIOCGETP TCGETA
-#undef TIOCSETN
-#define TIOCSETN TCSETA
-#undef TIOCSETP
-#define TIOCSETP TCSETAF
-#define TERMINAL struct termio
-#else /* ! HAVE_TERMIO_H */
-#ifdef HAVE_SGTTY_H
-#define HAVE_SGTTY
-#include <fcntl.h>
-#include <sgtty.h>
-#include <sys/ioctl.h>
-#define TERMINAL struct sgttyb
-#endif
-#endif
-#endif
-
-#endif /* !defined (TERMINAL_H) */