master 211ca9f916: Fix drag-and-drop button button flags

[Po Lu]

branch: master
commit 211ca9f916a3fa8c0ad1dce1519462584bee4467
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Fix drag-and-drop button button flags
    
    * src/xterm.c (x_dnd_send_position): Always send buttons
    regardless of version.  Fix bit indices.
    (handle_one_xevent): Likewise.
---
 src/xterm.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/src/xterm.c b/src/xterm.c
index 94cfe6f010..3894da7ab6 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -4469,21 +4469,22 @@ x_dnd_send_position (struct frame *f, Window target, 
int supported,
   msg.xclient.data.l[0] = FRAME_X_WINDOW (f);
   msg.xclient.data.l[1] = 0;
 
-  if (supported >= 5)
+  /* This is problematic because it's not specified in the
+     freedesktop.org copy of the protocol specification, but the copy
+     maintained by the original author of the protocol specifies it
+     for all versions.  Since at least one program supports these
+     flags, but uses protocol v4 (and not v5), set them for all
+     protocool versions.  */
+  if (button >= 4 && button <= 7)
     {
-      if (button >= 4 && button <= 7)
-       {
-         msg.xclient.data.l[1] |= (1 << 9);
-         msg.xclient.data.l[1] |= (button - 4) << 7;
-       }
-      else if (button)
-       return;
-
-      msg.xclient.data.l[1] |= state & 0x3f;
+      msg.xclient.data.l[1] |= (1 << 10);
+      msg.xclient.data.l[1] |= (button - 4) << 8;
     }
   else if (button)
     return;
 
+  msg.xclient.data.l[1] |= state & 0xff;
+
   msg.xclient.data.l[2] = (root_x << 16) | root_y;
   msg.xclient.data.l[3] = 0;
   msg.xclient.data.l[4] = 0;
@@ -4508,7 +4509,7 @@ x_dnd_send_position (struct frame *f, Window target, int 
supported,
          && x_dnd_mouse_rect.height
          /* Ignore the mouse rectangle if we're supposed to be sending a
             button press instead.  */
-         && (supported < 5 || !button))
+         && button)
        {
          if (root_x >= x_dnd_mouse_rect.x
              && root_x < (x_dnd_mouse_rect.x
@@ -16449,7 +16450,7 @@ handle_one_xevent (struct x_display_info *dpyinfo,
                        /* Ignore the mouse rectangle if we're
                           supposed to be sending a button press
                           instead.  */
-                       && (x_dnd_last_protocol_version < 5 || !button)
+                       && !button
                        && (root_x >= x_dnd_mouse_rect.x
                            && root_x < (x_dnd_mouse_rect.x
                                         + x_dnd_mouse_rect.width)