Re: [PATCH v2 2/6] Share parts of gdb/terminal.h with gdbserver

[Luis Machado <lgustavo@codesourcery.com>]

On 01/18/2017 09:36 AM, Sergio Durigan Junior wrote:
> As part of the bigger work of sharing fork_inferior with gdbserver,
> some parts of gdb/terminal.h also needed to be moved to a common
> place.  These parts are:
>
> - The code responsible for determining some terminal-based define's
>   based on available features;
>
> - job control;
>
> - terminal-related functions needed by fork_inferior;
>
> gdb/ChangeLog:
> 2017-01-17  Sergio Durigan Junior  <sergiodj@redhat.com>
>
> 	* Makefile.in (HFILES_NO_SRCDIR): Add "common/common-terminal.h".
> 	* common/common-terminal.h: New file, with parts of "terminal.h".
> 	* terminal.h: Move terminal-related defines to
> 	"common/common-terminal.h".  Include "common/common-terminal.h".
> 	(new_tty_prefork): Move to "common/common-terminal.h".
> 	(new_tty): Likewise.
> 	(new_tty_postfork): Likewise.
> 	(job_control): Likewise.
> 	(create_tty_session): Likewise.
> 	(gdb_setpgid): Likewise.
> 	* utils.c: Include "terminal.h".
>
> gdb/gdbserver/ChangeLog:
> 2016-12-22  Sergio Durigan Junior  <sergiodj@redhat.com>
>
> 	* terminal.c: New file.
> ---
>  gdb/Makefile.in              |   1 +
>  gdb/common/common-terminal.h | 119 +++++++++++++++++++++++++++++++++++++++++++
>  gdb/gdbserver/terminal.c     |  88 ++++++++++++++++++++++++++++++++
>  gdb/terminal.h               |  73 +-------------------------
>  gdb/utils.c                  |   1 +
>  5 files changed, 210 insertions(+), 72 deletions(-)
>  create mode 100644 gdb/common/common-terminal.h
>  create mode 100644 gdb/gdbserver/terminal.c
>
> diff --git a/gdb/Makefile.in b/gdb/Makefile.in
> index 3f19818..c05d456 100644
> --- a/gdb/Makefile.in
> +++ b/gdb/Makefile.in
> @@ -1469,6 +1469,7 @@ HFILES_NO_SRCDIR = \
>  	common/common-regcache.h \
>  	common/common-types.h \
>  	common/common-utils.h \
> +	common/common-terminal.h \
>  	common/errors.h \
>  	common/environ.h \
>  	common/fileio.h \
> diff --git a/gdb/common/common-terminal.h b/gdb/common/common-terminal.h
> new file mode 100644
> index 0000000..f7ab96a
> --- /dev/null
> +++ b/gdb/common/common-terminal.h
> @@ -0,0 +1,119 @@
> +/* Common terminal interface definitions for GDB and gdbserver.
> +   Copyright (C) 1986-2017 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/>.  */
> +
> +#ifndef COMMON_TERMINAL_H
> +#define COMMON_TERMINAL_H
> +
> +/* If we're using autoconf, it will define HAVE_TERMIOS_H,
> +   HAVE_TERMIO_H and HAVE_SGTTY_H for us.  One day we can rewrite
> +   ser-unix.c and inflow.c to inspect those names instead of
> +   HAVE_TERMIOS, HAVE_TERMIO and the implicit HAVE_SGTTY (when neither
> +   HAVE_TERMIOS or HAVE_TERMIO is set).  Until then, make sure that
> +   nothing has already defined the one of the names, and do the right
> +   thing.  */
> +
> +#if !defined (HAVE_TERMIOS) && !defined(HAVE_TERMIO) && !defined(HAVE_SGTTY)
> +#if defined(HAVE_TERMIOS_H)
> +#define HAVE_TERMIOS
> +#else /* ! defined (HAVE_TERMIOS_H) */
> +#if defined(HAVE_TERMIO_H)
> +#define HAVE_TERMIO
> +#else /* ! defined (HAVE_TERMIO_H) */
> +#if defined(HAVE_SGTTY_H)
> +#define HAVE_SGTTY
> +#endif /* ! defined (HAVE_SGTTY_H) */
> +#endif /* ! defined (HAVE_TERMIO_H) */
> +#endif /* ! defined (HAVE_TERMIOS_H) */
> +#endif /* !defined (HAVE_TERMIOS) && !defined (HAVE_TERMIO) &&
> +	  !defined (HAVE_SGTTY) */
> +
> +#if defined(HAVE_TERMIOS)
> +#include <termios.h>
> +#endif
> +
> +#if !defined(_WIN32) && !defined (HAVE_TERMIOS)
> +
> +/* Define a common set of macros -- BSD based -- and redefine whatever
> +   the system offers to make it look like that.  FIXME: serial.h and
> +   ser-*.c deal with this in a much cleaner fashion; as soon as stuff
> +   is converted to use them, can get rid of this crap.  */
> +
> +#ifdef 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 /* sgtty */
> +
> +#include <fcntl.h>
> +#include <sgtty.h>
> +#include <sys/ioctl.h>
> +#define TERMINAL struct sgttyb
> +
> +#endif /* sgtty */
> +#endif
> +
> +#include <sys/types.h>
> +
> +/* Do we have job control?  Can be assumed to always be the same
> +   within a given run of GDB.  Use in gdb/inflow.c and
> +   common/common-inflow.c.  */
> +extern int job_control;
> +
> +extern void new_tty (void);
> +
> +/* NEW_TTY_PREFORK is called before forking a new child process,
> +   so we can record the state of ttys in the child to be formed.
> +   TTYNAME is null if we are to share the terminal with gdb;

This is still referencing only gdb, but the code is now shared with 
gdbserver as well.

> +   or points to a string containing the name of the desired tty.
> +
> +   NEW_TTY is called in new child processes under Unix, which will
> +   become debugger target processes.  This actually switches to
> +   the terminal specified in the NEW_TTY_PREFORK call.  */
> +extern void new_tty_prefork (const char *ttyname);
> +
> +/* NEW_TTY_POSTFORK is called after forking a new child process, and
> +   adding it to the inferior table, to store the TTYNAME being used by
> +   the child, or null if it sharing the terminal with gdb.  */

Here as well.

> +extern void new_tty_postfork (void);
> +
> +/* Create a new session if the inferior will run in a different tty.
> +   A session is UNIX's way of grouping processes that share a controlling
> +   terminal, so a new one is needed if the inferior terminal will be
> +   different from GDB's.

And here.

> +
> +   Returns the session id of the new session, 0 if no session was created
> +   or -1 if an error occurred.  */
> +extern pid_t create_tty_session (void);
> +
> +/* Set the process group of the caller to its own pid, or do nothing
> +   if we lack job control.  */
> +extern int gdb_setpgid (void);
> +
> +/* Determine whether we have job control, and set variable JOB_CONTROL
> +   accordingly.  */
> +extern void have_job_control (void);
> +
> +#endif /* ! COMMON_TERMINAL_H */
> diff --git a/gdb/gdbserver/terminal.c b/gdb/gdbserver/terminal.c
> new file mode 100644
> index 0000000..42ac651
> --- /dev/null
> +++ b/gdb/gdbserver/terminal.c
> @@ -0,0 +1,88 @@
> +/* Terminal interface definitions for the GDB remote server.
> +   Copyright (C) 2016-2017 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/>.  */
> +
> +#include "server.h"
> +#include "common-terminal.h"
> +
> +/* See common/common-terminal.h.  */
> +
> +void
> +new_tty (void)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +}
> +
> +/* See common/common-terminal.h.  */
> +
> +void
> +new_tty_prefork (const char *ttyname)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +}
> +
> +/* See common/common-terminal.h.  */
> +
> +void
> +new_tty_postfork (void)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +}
> +
> +/* See common/common-terminal.h.  */
> +
> +pid_t
> +create_tty_session (void)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +  return (pid_t) 1;
> +}
> +
> +/* See common/common-inferior.h.  */
> +
> +void
> +set_inferior_io_terminal (const char *terminal_name)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +}
> +
> +/* See common/common-inferior.h.  */
> +
> +const char *
> +get_inferior_io_terminal (void)
> +{
> +  /* Placeholder needed by fork_inferior.  For now, this function is
> +     not needed nor useful to have on gdbserver.  When/If we properly
> +     handle terminal modes, we can revisit and implement the needed
> +     support.  */
> +  return NULL;
> +}
> diff --git a/gdb/terminal.h b/gdb/terminal.h
> index d8691b2..8139319 100644
> --- a/gdb/terminal.h
> +++ b/gdb/terminal.h
> @@ -19,83 +19,12 @@
>  #if !defined (TERMINAL_H)
>  #define TERMINAL_H 1
>
> -
> -/* If we're using autoconf, it will define HAVE_TERMIOS_H,
> -   HAVE_TERMIO_H and HAVE_SGTTY_H for us.  One day we can rewrite
> -   ser-unix.c and inflow.c to inspect those names instead of
> -   HAVE_TERMIOS, HAVE_TERMIO and the implicit HAVE_SGTTY (when neither
> -   HAVE_TERMIOS or HAVE_TERMIO is set).  Until then, make sure that
> -   nothing has already defined the one of the names, and do the right
> -   thing.  */
> -
> -#if !defined (HAVE_TERMIOS) && !defined(HAVE_TERMIO) && !defined(HAVE_SGTTY)
> -#if defined(HAVE_TERMIOS_H)
> -#define HAVE_TERMIOS
> -#else /* ! defined (HAVE_TERMIOS_H) */
> -#if defined(HAVE_TERMIO_H)
> -#define HAVE_TERMIO
> -#else /* ! defined (HAVE_TERMIO_H) */
> -#if defined(HAVE_SGTTY_H)
> -#define HAVE_SGTTY
> -#endif /* ! defined (HAVE_SGTTY_H) */
> -#endif /* ! defined (HAVE_TERMIO_H) */
> -#endif /* ! defined (HAVE_TERMIOS_H) */
> -#endif /* !defined (HAVE_TERMIOS) && !defined (HAVE_TERMIO) &&
> -	  !defined (HAVE_SGTTY) */
> -
> -#if defined(HAVE_TERMIOS)
> -#include <termios.h>
> -#endif
> -
> -#if !defined(_WIN32) && !defined (HAVE_TERMIOS)
> -
> -/* Define a common set of macros -- BSD based -- and redefine whatever
> -   the system offers to make it look like that.  FIXME: serial.h and
> -   ser-*.c deal with this in a much cleaner fashion; as soon as stuff
> -   is converted to use them, can get rid of this crap.  */
> -
> -#ifdef 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 /* sgtty */
> -
> -#include <fcntl.h>
> -#include <sgtty.h>
> -#include <sys/ioctl.h>
> -#define TERMINAL struct sgttyb
> -
> -#endif /* sgtty */
> -#endif
> +#include "common-terminal.h"
>
>  struct inferior;
>
> -extern void new_tty_prefork (const char *);
> -
> -extern void new_tty (void);
> -
> -extern void new_tty_postfork (void);
> -
>  extern void copy_terminal_info (struct inferior *to, struct inferior *from);
>
> -/* Do we have job control?  Can be assumed to always be the same within
> -   a given run of GDB.  In inflow.c.  */
> -extern int job_control;
> -
> -extern pid_t create_tty_session (void);
> -
> -/* Set the process group of the caller to its own pid, or do nothing if
> -   we lack job control.  */
> -extern int gdb_setpgid (void);
> -
>  /* Set up a serial structure describing standard input.  In inflow.c.  */
>  extern void initialize_stdin_serial (void);
>
> diff --git a/gdb/utils.c b/gdb/utils.c
> index f142ffe..4993145 100644
> --- a/gdb/utils.c
> +++ b/gdb/utils.c
> @@ -53,6 +53,7 @@
>  #include "top.h"
>  #include "main.h"
>  #include "solist.h"
> +#include "terminal.h"
>
>  #include "inferior.h"		/* for signed_pointer_to_address */
>
>