Move content_in_use to tui_source_window class

From scanning the source now, it's clear that the content_in_use field
is only used for the source window.  This patch moves the field there,
and changes it to be a bool at the same time.  (A future patch will
clean this up further, removing the field entirely.)

gdb/ChangeLog
2019-07-17  Tom Tromey  <tom@tromey.com>

	* tui/tui-winsource.c (tui_clear_source_content)
	(tui_show_source_content, tui_show_exec_info_content)
	(tui_clear_exec_info_content): Update.
	* tui/tui-stack.c (tui_show_locator_content): Update.
	(tui_show_frame_info): Update.
	* tui/tui-source.h (tui_source_window): Don't declare.
	* tui/tui-source.c (tui_source_window::showing_source_p): Rename
	from tui_source_is_displayed.
	* tui/tui-data.h (struct tui_gen_win_info) <content_in_use>:
	Remove field.
	(struct tui_source_window_base) <content_in_use>: New field.  Now
	bool.
	(struct tui_source_window) <showing_source_p>: New method.
	(TUI_SRC_WIN): Change cast.
	* tui/tui-data.c (tui_initialize_static_data): Update.

gdb/ChangeLog

@@ -1,3 +1,21 @@
+2019-07-17  Tom Tromey  <tom@tromey.com>
+
+	* tui/tui-winsource.c (tui_clear_source_content)
+	(tui_show_source_content, tui_show_exec_info_content)
+	(tui_clear_exec_info_content): Update.
+	* tui/tui-stack.c (tui_show_locator_content): Update.
+	(tui_show_frame_info): Update.
+	* tui/tui-source.h (tui_source_window): Don't declare.
+	* tui/tui-source.c (tui_source_window::showing_source_p): Rename
+	from tui_source_is_displayed.
+	* tui/tui-data.h (struct tui_gen_win_info) <content_in_use>:
+	Remove field.
+	(struct tui_source_window_base) <content_in_use>: New field.  Now
+	bool.
+	(struct tui_source_window) <showing_source_p>: New method.
+	(TUI_SRC_WIN): Change cast.
+	* tui/tui-data.c (tui_initialize_static_data): Update.
+
 2019-07-17  Tom Tromey  <tom@tromey.com>
 
 	* tui/tui-winsource.c (tui_update_breakpoint_info): Use

gdb/tui/tui-data.c

@@ -321,7 +321,6 @@ tui_initialize_static_data ()
     win->viewport_height =
     win->last_visible_line = 0;
   win->handle = NULL;
-  win->content_in_use = FALSE;
   win->is_visible = false;
   win->title = 0;
 }

gdb/tui/tui-data.h

@@ -75,8 +75,6 @@ public:
   int height = 0;
   /* Origin of window.  */
   struct tui_point origin = {0, 0};
-  /* Can it be used, or is it already used?  */
-  int content_in_use = FALSE;
   /* Viewport height.  */
   int viewport_height = 0;
   /* Index of last visible line.  */
@@ -408,6 +406,8 @@ public:
      LINE_NO in this source window; false otherwise.  */
   virtual bool location_matches_p (struct bp_location *loc, int line_no) = 0;
 
+  /* Can it be used, or is it already used?  */
+  bool content_in_use = false;
   /* Does the locator belong to this window?  */
   bool m_has_locator = false;
   /* Execution information window.  */
@@ -441,6 +441,8 @@ struct tui_source_window : public tui_source_window_base
 
   bool location_matches_p (struct bp_location *loc, int line_no) override;
 
+  bool showing_source_p (const char *filename) const;
+
 protected:
 
   void do_scroll_vertical (int num_to_scroll) override;
@@ -610,7 +612,7 @@ extern int tui_win_is_auxiliary (enum tui_win_type win_type);
 /* Global Data.  */
 extern struct tui_win_info *tui_win_list[MAX_MAJOR_WINDOWS];
 
-#define TUI_SRC_WIN     ((tui_source_window_base *) tui_win_list[SRC_WIN])
+#define TUI_SRC_WIN     ((tui_source_window *) tui_win_list[SRC_WIN])
 #define TUI_DISASM_WIN	((tui_source_window_base *) tui_win_list[DISASSEM_WIN])
 #define TUI_DATA_WIN    ((tui_data_window *) tui_win_list[DATA_WIN])
 #define TUI_CMD_WIN     ((tui_cmd_window *) tui_win_list[CMD_WIN])

gdb/tui/tui-source.c

@@ -287,11 +287,10 @@ tui_show_symtab_source (tui_source_window_base *win_info,
 
 /* Answer whether the source is currently displayed in the source
    window.  */
-int
+bool
-tui_source_is_displayed (const char *fullname)
+tui_source_window::showing_source_p (const char *fullname) const
 {
-  return (TUI_SRC_WIN != NULL
+  return (content_in_use 
-	  && TUI_SRC_WIN->content_in_use 
 	  && (filename_cmp (tui_locator_win_info_ptr ()->full_name,
 			    fullname) == 0));
 }

gdb/tui/tui-source.h

@@ -37,6 +37,5 @@ extern void tui_show_symtab_source (tui_source_window_base *,
 				    struct gdbarch *, struct symtab *,
 				    struct tui_line_or_address,
 				    int);
-extern int tui_source_is_displayed (const char *);
 
 #endif /* TUI_TUI_SOURCE_H */

gdb/tui/tui-stack.c

@@ -266,7 +266,6 @@ tui_show_locator_content (void)
       locator->refresh_window ();
       wmove (locator->handle, 0, 0);
       xfree (string);
-      locator->content_in_use = TRUE;
     }
 }
 
@@ -347,14 +346,19 @@ tui_show_frame_info (struct frame_info *fi)
 
       symtab_and_line sal = find_frame_sal (fi);
 
-      source_already_displayed = sal.symtab != 0
+      const char *fullname = nullptr;
-        && tui_source_is_displayed (symtab_to_fullname (sal.symtab));
+      if (sal.symtab != nullptr)
+	fullname = symtab_to_fullname (sal.symtab);
+
+      source_already_displayed = (sal.symtab != 0
+				  && TUI_SRC_WIN != nullptr
+				  && TUI_SRC_WIN->showing_source_p (fullname));
 
       if (get_frame_pc_if_available (fi, &pc))
 	locator_changed_p
 	  = tui_set_locator_info (get_frame_arch (fi),
 				  (sal.symtab == 0
-				   ? "??" : symtab_to_fullname (sal.symtab)),
+				   ? "??" : fullname),
 				  tui_get_function_from_frame (fi),
 				  sal.line,
 				  pc);

gdb/tui/tui-winsource.c

@@ -212,7 +212,7 @@ tui_clear_source_content (struct tui_source_window_base *win_info,
     {
       int i;
 
-      win_info->content_in_use = FALSE;
+      win_info->content_in_use = false;
       tui_erase_source_content (win_info, display_prompt);
       for (i = 0; i < win_info->content.size (); i++)
 	{
@@ -306,7 +306,7 @@ tui_show_source_content (struct tui_source_window_base *win_info)
 
   tui_check_and_display_highlight_if_needed (win_info);
   win_info->refresh_window ();
-  win_info->content_in_use = TRUE;
+  win_info->content_in_use = true;
 }
 
 /* See tui-data.h.  */
@@ -531,7 +531,6 @@ tui_show_exec_info_content (struct tui_source_window_base *win_info)
 	       0,
 	       content[cur_line - 1]);
   exec_info->refresh_window ();
-  exec_info->content_in_use = TRUE;
 }
 
 
@@ -547,7 +546,6 @@ tui_erase_exec_info_content (struct tui_source_window_base *win_info)
 void
 tui_clear_exec_info_content (struct tui_source_window_base *win_info)
 {
-  win_info->execution_info->content_in_use = FALSE;
   tui_erase_exec_info_content (win_info);
 }