* termhooks.h (enum scroll_bar_part): Begin from 0 to allow...

(struct input_event): ...unsigned bitfields.  Likewise for
`event_kind' member.  Prefer unsigned for `code' and 'modifiers'.
Use `timestamp' for HELP_EVENT position.  Add compile-time assert.
* keyboard.c (gen_help_event, kbd_buffer_store_help_event)
(kbd_buffer_get_event): Adjust users.
(scroll_bar_parts): Add Qnil to match scroll_bar_nowhere.
(make_scroll_bar_position): New function, refactored out of...
(make_lispy_event): ...adjusted user.
* nsterm.h (EmacsScroller): Use enum for `last_hit_part' member.
* nsterm.m (ns_mouse_position, mouseUp):
* term.c (term_mouse_position):
* w32inevt.c (w32_console_mouse_position):
* w32term.c (w32_mouse_position):
* xterm.c (XTmouse_position): Use scroll_bar_above_handle.
(x_send_scroll_bar_event, xm_scroll_callback, xg_scroll_callback):
Prefer enum and explicit enum members to integers and numeric values.

1 files changed, 11 insertions, 8 deletions

diff --git a/src/xterm.c b/src/xterm.c
index e24e86ce412..89a7453b953 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -4157,7 +4157,7 @@ XTmouse_position (struct frame **fp, int insist, Lisp_Object *bar_window,
             dpyinfo->last_mouse_glyph_frame = f1;
 
             *bar_window = Qnil;
-            *part = 0;
+            *part = scroll_bar_above_handle;
             *fp = f1;
             XSETINT (*x, win_x);
             XSETINT (*y, win_y);
@@ -4250,7 +4250,8 @@ x_window_to_menu_bar (Window window)
 
 #ifdef USE_TOOLKIT_SCROLL_BARS
 
-static void x_send_scroll_bar_event (Lisp_Object, int, int, int, bool);
+static void x_send_scroll_bar_event (Lisp_Object, enum scroll_bar_part,
+                                     int, int, bool);
 
 /* Lisp window being scrolled.  Set when starting to interact with
    a toolkit scroll bar, reset to nil when ending the interaction.  */
@@ -4371,7 +4372,8 @@ xt_horizontal_action_hook (Widget widget, XtPointer client_data, String action_n
    amount to scroll of a whole of WHOLE.  */
 
 static void
-x_send_scroll_bar_event (Lisp_Object window, int part, int portion, int whole, bool horizontal)
+x_send_scroll_bar_event (Lisp_Object window, enum scroll_bar_part part,
+                         int portion, int whole, bool horizontal)
 {
   XEvent event;
   XClientMessageEvent *ev = &event.xclient;
@@ -4504,8 +4506,8 @@ xm_scroll_callback (Widget widget, XtPointer client_data, XtPointer call_data)
 {
   struct scroll_bar *bar = client_data;
   XmScrollBarCallbackStruct *cs = call_data;
-  int part = -1, whole = 0, portion = 0;
-  int horizontal = bar->horizontal;
+  enum scroll_bar_part part = scroll_bar_nowhere;
+  int horizontal = bar->horizontal, whole = 0, portion = 0;
 
   switch (cs->reason)
     {
@@ -4569,7 +4571,7 @@ xm_scroll_callback (Widget widget, XtPointer client_data, XtPointer call_data)
       break;
     };
 
-  if (part >= 0)
+  if (part != scroll_bar_nowhere)
     {
       window_being_scrolled = bar->window;
       x_send_scroll_bar_event (bar->window, part, portion, whole, bar->horizontal);
@@ -4587,8 +4589,9 @@ xg_scroll_callback (GtkRange     *range,
                     gdouble       value,
                     gpointer      user_data)
 {
+  int whole = 0, portion = 0;
   struct scroll_bar *bar = user_data;
-  int part = -1, whole = 0, portion = 0;
+  enum scroll_bar_part part = scroll_bar_nowhere;
   GtkAdjustment *adj = GTK_ADJUSTMENT (gtk_range_get_adjustment (range));
   struct frame *f = g_object_get_data (G_OBJECT (range), XG_FRAME_DATA);
 
@@ -4641,7 +4644,7 @@ xg_scroll_callback (GtkRange     *range,
       break;
     }
 
-  if (part >= 0)
+  if (part != scroll_bar_nowhere)
     {
       window_being_scrolled = bar->window;
       x_send_scroll_bar_event (bar->window, part, portion, whole, bar->horizontal);