Move parts of inferior job control to common/

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:
2017-06-07  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:
2017-06-07  Sergio Durigan Junior  <sergiodj@redhat.com>

	* Makefile.in (SFILE): Add "common/job-control.c".
	(OBS): Add "job-control.o".

1 files changed, 3 insertions, 61 deletions

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);