Reimplement TUI "C-x 1" binding

The TUI "C-x 1" key binding removes TUI windows, based on the current
layout.  With user-defined layouts, this is no longer easy to do.

This patch changes "C-x 1" to simply delete windows, leaving just the
focus window, the locator, and the command window.

gdb/ChangeLog
2020-02-22  Tom Tromey  <tom@tromey.com>

	* tui/tui.c (tui_rl_delete_other_windows): Call
	tui_remove_some_windows.
	* tui/tui-layout.h (class tui_layout_base) <remove_windows>:
	Declare method.
	(class tui_layout_window) <remove_windows>: New method.
	(class tui_layout_split) <remove_windows>: Declare.
	(tui_remove_some_windows): Declare.
	* tui/tui-layout.c (tui_remove_some_windows): New function.
	(tui_layout_split::remove_windows): New method.

Change-Id: If186f9c3f263913e963b965204481d1b4385c6d4

gdb/ChangeLog

@@ -1,3 +1,15 @@
+2020-02-22  Tom Tromey  <tom@tromey.com>
+
+	* tui/tui.c (tui_rl_delete_other_windows): Call
+	tui_remove_some_windows.
+	* tui/tui-layout.h (class tui_layout_base) <remove_windows>:
+	Declare method.
+	(class tui_layout_window) <remove_windows>: New method.
+	(class tui_layout_split) <remove_windows>: Declare.
+	(tui_remove_some_windows): Declare.
+	* tui/tui-layout.c (tui_remove_some_windows): New function.
+	(tui_layout_split::remove_windows): New method.
+
 2020-02-22  Tom Tromey  <tom@tromey.com>
 
 	* tui/tui.c (tui_rl_change_windows): Call tui_next_layout.

gdb/tui/tui-layout.c

@@ -286,6 +286,28 @@ tui_next_layout ()
   tui_layout_command ("next", 0);
 }
 
+/* See tui-layout.h.  */
+
+void
+tui_remove_some_windows ()
+{
+  tui_win_info *focus = tui_win_with_focus ();
+
+  if (strcmp (focus->name (), "cmd") == 0)
+    {
+      /* Try leaving the source or disassembly window.  If neither
+	 exists, just do nothing.  */
+      focus = TUI_SRC_WIN;
+      if (focus == nullptr)
+	focus = TUI_DISASM_WIN;
+      if (focus == nullptr)
+	return;
+    }
+
+  applied_layout->remove_windows (focus->name ());
+  tui_apply_current_layout ();
+}
+
 static void
 extract_display_start_addr (struct gdbarch **gdbarch_p, CORE_ADDR *addr_p)
 {
@@ -751,6 +773,29 @@ tui_layout_split::apply (int x_, int y_, int width_, int height_)
   m_applied = true;
 }
 
+/* See tui-layout.h.  */
+
+void
+tui_layout_split::remove_windows (const char *name)
+{
+  for (int i = 0; i < m_splits.size (); ++i)
+    {
+      const char *this_name = m_splits[i].layout->get_name ();
+      if (this_name == nullptr)
+	m_splits[i].layout->remove_windows (name);
+      else
+	{
+	  if (strcmp (this_name, name) == 0
+	      || strcmp (this_name, "cmd") == 0)
+	    {
+	      /* Keep.  */
+	    }
+	  m_splits.erase (m_splits.begin () + i);
+	  --i;
+	}
+    }
+}
+
 static void
 initialize_layouts ()
 {

gdb/tui/tui-layout.h

@@ -64,6 +64,10 @@ public:
      the sizes of the other windows around it.  */
   virtual bool adjust_size (const char *name, int new_height) = 0;
 
+  /* Remove some windows from the layout, leaving the command window
+     and the window being passed in here.  */
+  virtual void remove_windows (const char *name) = 0;
+
   /* The most recent space allocation.  */
   int x = 0;
   int y = 0;
@@ -106,6 +110,10 @@ public:
 
   bool bottom_boxed_p () const override;
 
+  void remove_windows (const char *name) override
+  {
+  }
+
 protected:
 
   void get_sizes (int *min_height, int *max_height) override;
@@ -149,6 +157,8 @@ public:
 
   bool bottom_boxed_p () const override;
 
+  void remove_windows (const char *name) override;
+
 protected:
 
   void get_sizes (int *min_height, int *max_height) override;
@@ -184,6 +194,11 @@ extern void tui_set_layout (enum tui_layout_type);
 /* Switch to the next layout.  */
 extern void tui_next_layout ();
 
+/* Remove some windows from the layout, leaving only the focused
+   window and the command window; if no window has the focus, then
+   some other window is chosen to remain.  */
+extern void tui_remove_some_windows ();
+
 /* Apply the current layout.  */
 extern void tui_apply_current_layout ();
 

gdb/tui/tui.c

@@ -162,28 +162,8 @@ tui_rl_delete_other_windows (int notused1, int notused2)
     tui_rl_switch_mode (0 /* notused */, 0 /* notused */);
 
   if (tui_active)
-    {
-      enum tui_layout_type new_layout;
+    tui_remove_some_windows ();
 
-      new_layout = tui_current_layout ();
-
-      /* Kill one window.  */
-      switch (new_layout)
-	{
-	case SRC_COMMAND:
-	case SRC_DATA_COMMAND:
-	case SRC_DISASSEM_COMMAND:
-	default:
-	  new_layout = SRC_COMMAND;
-	  break;
-
-	case DISASSEM_COMMAND:
-	case DISASSEM_DATA_COMMAND:
-	  new_layout = DISASSEM_COMMAND;
-	  break;
-	}
-      tui_set_layout (new_layout);
-    }
   return 0;
 }