gdb/inflow.c: Move SIGTTOU temporary ignoring to a RAII class

I expect to use this in more places (in inflow.c) in follow up
patches, but I think this is still good on its own.

gdb/ChangeLog:
2017-11-16  Pedro Alves  <palves@redhat.com>

	* inflow.c (scoped_ignore_sigttou): New class.
	(child_terminal_ours_1, new_tty): Use it.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index df10fe509dcdac47580f45ddf5a0e27549f1f0c2..52bd6156254cb12c9a51c65abdd034e833e3f066 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2017-11-16  Pedro Alves  <palves@redhat.com>
+
+       * inflow.c (scoped_ignore_sigttou): New class.
+       (child_terminal_ours_1, new_tty): Use it.
+
 2017-11-16  Ulrich Weigand  <uweigand@de.ibm.com>
 
        * target-float.c (decimal_from_number): Add byte_order argument and

diff --git a/gdb/inflow.c b/gdb/inflow.c
index 0c279e6a9f3f9bd8e9bf42f0d3d09c002a903f9e..7c49246b6f2ad2fcc44db865f52b8c65af6995e2 100644 (file)
--- a/gdb/inflow.c
+++ b/gdb/inflow.c
@@ -91,6 +91,35 @@ 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
+};
+
 #ifdef HAVE_TERMIOS_H
 
 /* Return the process group of the current inferior.  */
@@ -329,17 +358,11 @@ child_terminal_ours_1 (int output_only)
     return;
   else
     {
-#ifdef SIGTTOU
-      /* Ignore this signal since it will happen when we try to set the
-         pgrp.  */
-      sighandler_t osigttou = NULL;
-#endif
       int result ATTRIBUTE_UNUSED;
 
-#ifdef SIGTTOU
-      if (job_control)
-       osigttou = signal (SIGTTOU, SIG_IGN);
-#endif
+      /* Ignore SIGTTOU since it will happen when we try to set the
+        terminal's pgrp.  */
+      scoped_ignore_sigttou ignore_sigttou;
 
       xfree (tinfo->ttystate);
       tinfo->ttystate = serial_get_tty_state (stdin_serial);
@@ -372,11 +395,6 @@ child_terminal_ours_1 (int output_only)
 #endif /* termios */
        }
 
-#ifdef SIGTTOU
-      if (job_control)
-       signal (SIGTTOU, osigttou);
-#endif
-
       if (!job_control)
        {
          signal (SIGINT, sigint_ours);
@@ -603,12 +621,10 @@ new_tty (void)
   tty = open ("/dev/tty", O_RDWR);
   if (tty > 0)
     {
-      sighandler_t osigttou;
+      scoped_ignore_sigttou ignore_sigttou;
 
-      osigttou = signal (SIGTTOU, SIG_IGN);
       ioctl (tty, TIOCNOTTY, 0);
       close (tty);
-      signal (SIGTTOU, osigttou);
     }
 #endif