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

[Sergio Durigan Junior <sergiodj at redhat dot com>]

Hey Luis,

Thanks for the review.  Comments below.

On Wednesday, February 01 2017, Luis Machado wrote:

> 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.

These are actually right (for now, at least), since they are just used
by GDB and their gdbserver counterpart are just placeholders.  I will
expand the comment to mention that.

>> +
>> +   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 */
>>
>>
>

Thanks,

-- 
Sergio
GPG key ID: 237A 54B1 0287 28BF 00EF  31F4 D0EB 7628 65FC 5E36
Please send encrypted e-mail if possible
http://sergiodj.net/