From FEDORA_PATCHES Mon Sep 17 00:00:00 2001

From: Alan Hayward <alan.hayward@arm.com>

Date: Tue, 28 May 2019 10:07:54 +0100

Subject: gdb-rhbz1852580-terminal-woes.patch

;; Fix terminal problems when error() is called

;; Alan Hayward (RH BZ 1852580)

Suppress SIGTTOU when handling errors

Calls to error () can cause SIGTTOU to send gdb to the background.

For example, on an Arm build:

  (gdb) b main

  Breakpoint 1 at 0x10774: file /build/gdb/testsuite/../../../src/binutils-gdb/gdb/testsuite/gdb.base/watchpoint.c, line 174.

  (gdb) r

  Starting program: /build/gdb/testsuite/outputs/gdb.base/watchpoint/watchpoint

  [1]+  Stopped                 ../gdb ./outputs/gdb.base/watchpoint/watchpoint

  localhost$ fg

  ../gdb ./outputs/gdb.base/watchpoint/watchpoint

  Cannot parse expression `.L1199 4@r4'.

  warning: Probes-based dynamic linker interface failed.

  Reverting to original interface.

The SIGTTOU is raised whilst inside a syscall during the call to tcdrain.

Fix is to use scoped_ignore_sigttou to ensure SIGTTOU is blocked.

In addition fix include comments - job_control is not included via terminal.h

gdb/ChangeLog:

	* event-top.c: Remove include comment.

	* inflow.c (class scoped_ignore_sigttou): Move from here...

	* inflow.h (class scoped_ignore_sigttou): ...to here.

	* ser-unix.c (hardwire_drain_output): Block SIGTTOU during drain.

	* top.c:  Remove include comment.

diff --git a/gdb/event-top.c b/gdb/event-top.c

--- a/gdb/event-top.c

+++ b/gdb/event-top.c

@@ -24,7 +24,7 @@

 #include "inferior.h"

 #include "infrun.h"

 #include "target.h"

-#include "terminal.h"		/* for job_control */

+#include "terminal.h"

 #include "event-loop.h"

 #include "event-top.h"

 #include "interps.h"

diff --git a/gdb/inflow.c b/gdb/inflow.c

--- a/gdb/inflow.c

+++ b/gdb/inflow.c

@@ -103,35 +103,6 @@ static serial_ttystate initial_gdb_ttystate;

 static struct terminal_info *get_inflow_inferior_data (struct inferior *);

-/* RAII class used to ignore SIGTTOU in a scope.  */

-

-class scoped_ignore_sigttou

-{

-public:

-  scoped_ignore_sigttou ()

-  {

-#ifdef SIGTTOU

-    if (job_control)

-      m_osigttou = signal (SIGTTOU, SIG_IGN);

-#endif

-  }

-

-  ~scoped_ignore_sigttou ()

-  {

-#ifdef SIGTTOU

-    if (job_control)

-      signal (SIGTTOU, m_osigttou);

-#endif

-  }

-

-  DISABLE_COPY_AND_ASSIGN (scoped_ignore_sigttou);

-

-private:

-#ifdef SIGTTOU

-  sighandler_t m_osigttou = NULL;

-#endif

-};

-

 /* While the inferior is running, we want SIGINT and SIGQUIT to go to the

    inferior only.  If we have job control, that takes care of it.  If not,

    we save our handlers in these two variables and set SIGINT and SIGQUIT

diff --git a/gdb/inflow.h b/gdb/inflow.h

--- a/gdb/inflow.h

+++ b/gdb/inflow.h

@@ -21,5 +21,36 @@

 #define INFLOW_H

 #include <unistd.h>

+#include <signal.h>

+#include "common/job-control.h"

+

+/* RAII class used to ignore SIGTTOU in a scope.  */

+

+class scoped_ignore_sigttou

+{

+public:

+  scoped_ignore_sigttou ()

+  {

+#ifdef SIGTTOU

+    if (job_control)

+      m_osigttou = signal (SIGTTOU, SIG_IGN);

+#endif

+  }

+

+  ~scoped_ignore_sigttou ()

+  {

+#ifdef SIGTTOU

+    if (job_control)

+      signal (SIGTTOU, m_osigttou);

+#endif

+  }

+

+  DISABLE_COPY_AND_ASSIGN (scoped_ignore_sigttou);

+

+private:

+#ifdef SIGTTOU

+  sighandler_t m_osigttou = NULL;

+#endif

+};

 #endif /* inflow.h */

diff --git a/gdb/ser-unix.c b/gdb/ser-unix.c

--- a/gdb/ser-unix.c

+++ b/gdb/ser-unix.c

@@ -32,6 +32,7 @@

 #include "gdbcmd.h"

 #include "filestuff.h"

 #include <termios.h>

+#include "inflow.h"

 struct hardwire_ttystate

   {

@@ -164,6 +165,9 @@ hardwire_print_tty_state (struct serial *scb,

 static int

 hardwire_drain_output (struct serial *scb)

 {

+  /* Ignore SIGTTOU which may occur during the drain.  */

+  scoped_ignore_sigttou ignore_sigttou;

+

   return tcdrain (scb->fd);

 }

diff --git a/gdb/top.c b/gdb/top.c

--- a/gdb/top.c

+++ b/gdb/top.c

@@ -34,8 +34,8 @@

 #include "expression.h"

 #include "value.h"

 #include "language.h"

-#include "terminal.h"		/* For job_control.  */

-#include "job-control.h"

+#include "terminal.h"

+#include "common/job-control.h"

 #include "annotate.h"

 #include "completer.h"

 #include "top.h"