[PATCH v7 1/4] Move parts of inferior job control to common/

Sergio Durigan Junior
2017-06-04T22:18:09Z

This commit moves a few bits responsible for dealing with inferior job
control from GDB to common/, which makes them available to gdbserver.
This is necessary for the upcoming patches that will share
fork_inferior et al between GDB and gdbserver.

We move some parts of gdb/terminal.h to gdb/common/common-terminal.h,
especifically the code that checks terminal features and that are used
to set job_control accordingly.

After sharing parts of gdb/terminal.h, we also to share the two
functions on gdb/inflow.c that are going to be needed by the
fork_inferior rework. They are 'gdb_setpgid' and the new
'have_job_control'. I've also taken the opportunity to give a more
meaningful name to "inflow.c" on common/. Now it is called
"job-control.c" (thanks Pedro for the suggestion).

gdb/ChangeLog:
yyyy-mm-dd Sergio Durigan Junior <sergiodj@redhat.com>

* Makefile.in (SFILES): Add "common/job-control.c".
(HFILES_NO_SRCDIR): Add "common/job-control.h".
(COMMON_OBS): Add "job-control.o".
* common/job-control.c: New file, with contents from
"gdb/inflow.c".
* common/job-control.h: New file, with contents from "terminal.h".
* fork-child.c: Include "job-control.h".
* inflow.c: Include "job-control.h".
(gdb_setpgid): Move to "common/common-inflow.c".
(_initialize_inflow): Move setting of "job_control" to
"handle_job_control".
* terminal.h (job_control): Moved to "common/common-terminal.h".
(gdb_setpgid): Likewise.
* top.c: Include "job_control.h".
* utils.c: Likewise.
(job_control): Moved to "job-control.c".

gdb/gdbserver/ChangeLog:
yyyy-mm-dd Sergio Durigan Junior <sergiodj@redhat.com>

* Makefile.in (SFILE): Add "common/job-control.c".
(OBS): Add "job-control.o".
---
gdb/Makefile.in | 3 ++
gdb/common/job-control.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++
gdb/common/job-control.h | 38 +++++++++++++++++++
gdb/fork-child.c | 1 +
gdb/gdbserver/Makefile.in | 2 +
gdb/inflow.c | 64 ++------------------------------
gdb/terminal.h | 12 ------
gdb/top.c | 1 +
gdb/utils.c | 5 +--
9 files changed, 142 insertions(+), 77 deletions(-)
create mode 100644 gdb/common/job-control.c
create mode 100644 gdb/common/job-control.h

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 8be73ba..25777f2 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -1234,6 +1234,7 @@ SFILES = \
common/fileio.c \
common/filestuff.c \
common/format.c \
+ common/job-control.c \
common/gdb_vecs.c \
common/new-op.c \
common/print-utils.c \
@@ -1509,6 +1510,7 @@ HFILES_NO_SRCDIR = \
common/common-regcache.h \
common/common-types.h \
common/common-utils.h \
+ common/job-control.h \
common/errors.h \
common/environ.h \
common/fileio.h \
@@ -1663,6 +1665,7 @@ COMMON_OBS = $(DEPFILES) $(CONFIG_OBS) $(YYOBJ) \
common-agent.o \
common-debug.o \
common-exceptions.o \
+ job-control.o \
common-regcache.o \
common-utils.o \
complaints.o \
diff --git a/gdb/common/job-control.c b/gdb/common/job-control.c
new file mode 100644
index 0000000..d76bc57
--- /dev/null
+++ b/gdb/common/job-control.c
@@ -0,0 +1,93 @@
+/* Job control and terminal related functions, for GDB and gdbserver
+ when running under Unix.
+
+ 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/>. */
+
+#include "common-defs.h"
+#include "job-control.h"
+#include "gdb_termios.h"
+
+/* Nonzero if we have job control. */
+int job_control;
+
+/* Set the process group ID of the inferior.
+
+ Just using job_control only does part of it because setpgid or
+ setpgrp might not exist on a system without job control.
+
+ For a more clean implementation, in libiberty, put a setpgid which merely
+ calls setpgrp and a setpgrp which does nothing (any system with job control
+ will have one or the other). */
+
+int
+gdb_setpgid ()
+{
+ int retval = 0;
+
+ if (job_control)
+ {
+#if defined (HAVE_TERMIOS) || defined (TIOCGPGRP)
+#ifdef HAVE_SETPGID
+ /* The call setpgid (0, 0) is supposed to work and mean the same
+ thing as this, but on Ultrix 4.2A it fails with EPERM (and
+ setpgid (getpid (), getpid ()) succeeds). */
+ retval = setpgid (getpid (), getpid ());
+#else
+#ifdef HAVE_SETPGRP
+#ifdef SETPGRP_VOID
+ retval = setpgrp ();
+#else
+ retval = setpgrp (getpid (), getpid ());
+#endif
+#endif /* HAVE_SETPGRP */
+#endif /* HAVE_SETPGID */
+#endif /* defined (HAVE_TERMIOS) || defined (TIOCGPGRP) */
+ }
+
+ return retval;
+}
+
+/* See common/common-terminal.h. */
+
+void
+have_job_control ()
+{
+ /* OK, figure out whether we have job control. If neither termios nor
+ sgtty (i.e. termio or go32), leave job_control 0. */
+#if defined (HAVE_TERMIOS)
+ /* Do all systems with termios have the POSIX way of identifying job
+ control? I hope so. */
+#ifdef _POSIX_JOB_CONTROL
+ job_control = 1;
+#else
+#ifdef _SC_JOB_CONTROL
+ job_control = sysconf (_SC_JOB_CONTROL);
+#else
+ job_control = 0; /* Have to assume the worst. */
+#endif /* _SC_JOB_CONTROL */
+#endif /* _POSIX_JOB_CONTROL */
+#endif /* HAVE_TERMIOS */
+
+#ifdef HAVE_SGTTY
+#ifdef TIOCGPGRP
+ job_control = 1;
+#else
+ job_control = 0;
+#endif /* TIOCGPGRP */
+#endif /* sgtty */
+}
diff --git a/gdb/common/job-control.h b/gdb/common/job-control.h
new file mode 100644
index 0000000..9e284aa
--- /dev/null
+++ b/gdb/common/job-control.h
@@ -0,0 +1,38 @@
+/* Job control and terminal related functions, for GDB and gdbserver
+ when running under Unix.
+
+ 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 JOB_CONTROL_H
+#define JOB_CONTROL_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;
+
+/* Set the process group of the caller to its own pid, or do nothing
+ if we lack job control. */
+extern int gdb_setpgid ();
+
+/* Determine whether we have job control, and set variable JOB_CONTROL
+ accordingly. This function must be called before any use of
+ JOB_CONTROL. */
+extern void have_job_control ();
+
+#endif /* ! JOB_CONTROL_H */
diff --git a/gdb/fork-child.c b/gdb/fork-child.c
index 11ffee9..c1b6f53 100644
--- a/gdb/fork-child.c
+++ b/gdb/fork-child.c
@@ -33,6 +33,7 @@
#include "filestuff.h"
#include "top.h"
#include "signals-state-save-restore.h"
+#include "job-control.h"
#include <signal.h>
#include <vector>

diff --git a/gdb/gdbserver/Makefile.in b/gdb/gdbserver/Makefile.in
index 01dfdc0..d9f55de 100644
--- a/gdb/gdbserver/Makefile.in
+++ b/gdb/gdbserver/Makefile.in
@@ -204,6 +204,7 @@ SFILES = \
$(srcdir)/common/environ.c \
$(srcdir)/common/fileio.c \
$(srcdir)/common/filestuff.c \
+ $(srcdir)/common/job-control.c \
$(srcdir)/common/gdb_vecs.c \
$(srcdir)/common/new-op.c \
$(srcdir)/common/print-utils.c \
@@ -234,6 +235,7 @@ OBS = \
cleanups.o \
common-debug.o \
common-exceptions.o \
+ job-control.o \
common-regcache.o \
common-utils.o \
debug.o \
diff --git a/gdb/inflow.c b/gdb/inflow.c
index 23dcc4d..01851f4 100644
--- a/gdb/inflow.c
+++ b/gdb/inflow.c
@@ -32,6 +32,7 @@
#include "inflow.h"
#include "gdbcmd.h"
#include "gdb_termios.h"
+#include "job-control.h"

#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
@@ -804,43 +805,6 @@ create_tty_session (void)
#endif /* HAVE_SETSID */
}

-/* This is here because this is where we figure out whether we (probably)
- have job control. Just using job_control only does part of it because
- setpgid or setpgrp might not exist on a system without job control.
- It might be considered misplaced (on the other hand, process groups and
- job control are closely related to ttys).
-
- For a more clean implementation, in libiberty, put a setpgid which merely
- calls setpgrp and a setpgrp which does nothing (any system with job control
- will have one or the other). */
-int
-gdb_setpgid (void)
-{
- int retval = 0;
-
- if (job_control)
- {
-#if defined (HAVE_TERMIOS) || defined (TIOCGPGRP)
-#ifdef HAVE_SETPGID
- /* The call setpgid (0, 0) is supposed to work and mean the same
- thing as this, but on Ultrix 4.2A it fails with EPERM (and
- setpgid (getpid (), getpid ()) succeeds). */
- retval = setpgid (getpid (), getpid ());
-#else
-#ifdef HAVE_SETPGRP
-#ifdef SETPGRP_VOID
- retval = setpgrp ();
-#else
- retval = setpgrp (getpid (), getpid ());
-#endif
-#endif /* HAVE_SETPGRP */
-#endif /* HAVE_SETPGID */
-#endif /* defined (HAVE_TERMIOS) || defined (TIOCGPGRP) */
- }
-
- return retval;
-}
-
/* Get all the current tty settings (including whether we have a
tty at all!). We can't do this in _initialize_inflow because
serial_fdopen() won't work until the serial_ops_list is
@@ -861,30 +825,8 @@ _initialize_inflow (void)

terminal_is_ours = 1;

- /* OK, figure out whether we have job control. If neither termios nor
- sgtty (i.e. termio or go32), leave job_control 0. */
-
-#if defined (HAVE_TERMIOS)
- /* Do all systems with termios have the POSIX way of identifying job
- control? I hope so. */
-#ifdef _POSIX_JOB_CONTROL
- job_control = 1;
-#else
-#ifdef _SC_JOB_CONTROL
- job_control = sysconf (_SC_JOB_CONTROL);
-#else
- job_control = 0; /* Have to assume the worst. */
-#endif /* _SC_JOB_CONTROL */
-#endif /* _POSIX_JOB_CONTROL */
-#endif /* HAVE_TERMIOS */
-
-#ifdef HAVE_SGTTY
-#ifdef TIOCGPGRP
- job_control = 1;
-#else
- job_control = 0;
-#endif /* TIOCGPGRP */
-#endif /* sgtty */
+ /* OK, figure out whether we have job control. */
+ have_job_control ();

observer_attach_inferior_exit (inflow_inferior_exit);

diff --git a/gdb/terminal.h b/gdb/terminal.h
index fb20ae0..0027a3a 100644
--- a/gdb/terminal.h
+++ b/gdb/terminal.h
@@ -29,16 +29,8 @@ 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);

@@ -48,8 +40,4 @@ extern void gdb_save_tty_state (void);
have had a chance to alter it. */
extern void set_initial_gdb_ttystate (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);
-
#endif /* !defined (TERMINAL_H) */
diff --git a/gdb/top.c b/gdb/top.c
index 3de8a26..17261cc 100644
--- a/gdb/top.c
+++ b/gdb/top.c
@@ -35,6 +35,7 @@
#include "value.h"
#include "language.h"
#include "terminal.h" /* For job_control. */
+#include "job-control.h"
#include "annotate.h"
#include "completer.h"
#include "top.h"
diff --git a/gdb/utils.c b/gdb/utils.c
index b4332f8..c61557e 100644
--- a/gdb/utils.c
+++ b/gdb/utils.c
@@ -65,6 +65,7 @@
#include "gdb_usleep.h"
#include "interps.h"
#include "gdb_regex.h"
+#include "job-control.h"

#if !HAVE_DECL_MALLOC
extern PTR malloc (); /* ARI: PTR */
@@ -102,10 +103,6 @@ static std::chrono::steady_clock::duration prompt_for_continue_wait_time;

static int debug_timestamp = 0;

-/* Nonzero if we have job control. */
-
-int job_control;
-
/* Nonzero means that strings with character values >0x7F should be printed
as octal escapes. Zero means just print the value (e.g. it's an
international character, and the terminal or window can cope.) */
--
2.9.3