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

Luis Machado
2017-02-01T18:37:44Z

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 */
>
>