Fix window selection by pointer.

This should fix things in WM’s using virtual roots as well as in tabbing WM’s.

Signed-off-by: James Cloos <cloos@jhcloos.com>

7 files changed, 256 insertions, 21 deletions

diff --git a/Makefile.am b/Makefile.am
index 0199d35..8e193a9 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -25,6 +25,8 @@ xwd_CFLAGS = $(XWD_CFLAGS)
 xwd_LDADD = $(XWD_LIBS)
 
 xwd_SOURCES =	\
+        clientwin.c \
+        clientwin.h \
         dsimple.c \
         dsimple.h \
         list.c \
diff --git a/clientwin.c b/clientwin.c
new file mode 100644
index 0000000..808adec
--- /dev/null
+++ b/clientwin.c
@@ -0,0 +1,214 @@
+/*
+ * Copyright 2007 Kim woelders
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+#include <X11/Xatom.h>
+#include <X11/Xlib.h>
+
+static Atom atom_wm_state = None;
+
+/*
+ * Check if window has given property
+ */
+static Bool
+Window_Has_Property(Display * dpy, Window win, Atom atom)
+{
+    Atom type_ret;
+    int format_ret;
+    unsigned char *prop_ret;
+    unsigned long bytes_after, num_ret;
+
+    type_ret = None;
+    prop_ret = NULL;
+    XGetWindowProperty(dpy, win, atom, 0, 0, False, AnyPropertyType,
+                       &type_ret, &format_ret, &num_ret,
+                       &bytes_after, &prop_ret);
+    if (prop_ret)
+        XFree(prop_ret);
+
+    return (type_ret != None) ? True : False;
+}
+
+/*
+ * Check if window is viewable
+ */
+static Bool
+Window_Is_Viewable(Display * dpy, Window win)
+{
+    Bool ok;
+    XWindowAttributes xwa;
+
+    XGetWindowAttributes(dpy, win, &xwa);
+
+    ok = (xwa.class == InputOutput) && (xwa.map_state == IsViewable);
+
+    return ok;
+}
+
+/*
+ * Find a window that has WM_STATE set in the window tree below win.
+ * Unmapped/unviewable windows are not considered valid matches.
+ * Children are searched in top-down stacking order.
+ * The first matching window is returned, None if no match is found.
+ */
+Window
+Find_Client_In_Children(Display * dpy, Window win)
+{
+    Window root, parent;
+    Window *children;
+    unsigned int n_children;
+    int i;
+
+    if (!XQueryTree(dpy, win, &root, &parent, &children, &n_children))
+        return None;
+    if (!children)
+        return None;
+
+    /* Check each child for WM_STATE and other validity */
+    win = None;
+    for (i = (int) n_children - 1; i >= 0; i--) {
+        if (!Window_Is_Viewable(dpy, children[i])) {
+            children[i] = None; /* Don't bother descending into this one */
+            continue;
+        }
+        if (!Window_Has_Property(dpy, children[i], atom_wm_state))
+            continue;
+
+        /* Got one */
+        win = children[i];
+        goto done;
+    }
+
+    /* No children matched, now descend into each child */
+    for (i = (int) n_children - 1; i >= 0; i--) {
+        if (children[i] == None)
+            continue;
+        win = Find_Client_In_Children(dpy, children[i]);
+        if (win != None)
+            break;
+    }
+
+  done:
+    XFree(children);
+
+    return win;
+}
+
+/*
+ * Find virtual roots (_NET_VIRTUAL_ROOTS)
+ */
+unsigned long *
+Find_Roots(Display * dpy, Window root, unsigned int *num)
+{
+    Atom type_ret;
+    int format_ret;
+    unsigned char *prop_ret;
+    unsigned long bytes_after, num_ret;
+    Atom atom;
+
+    *num = 0;
+    atom = XInternAtom(dpy, "_NET_VIRTUAL_ROOTS", False);
+    if (!atom)
+        return NULL;
+
+    type_ret = None;
+    prop_ret = NULL;
+    if (XGetWindowProperty(dpy, root, atom, 0, 0x7fffffff, False,
+                           XA_WINDOW, &type_ret, &format_ret, &num_ret,
+                           &bytes_after, &prop_ret) != Success)
+        return NULL;
+
+    if (prop_ret && type_ret == XA_WINDOW && format_ret == 32) {
+        *num = num_ret;
+        return ((unsigned long *) prop_ret);
+    }
+    if (prop_ret)
+        XFree(prop_ret);
+
+    return NULL;
+}
+
+/*
+ * Find child window at pointer location
+ */
+static Window
+Find_Child_At_Pointer(Display * dpy, Window win)
+{
+    Window root_return, child_return;
+    int dummyi;
+    unsigned int dummyu;
+
+    XQueryPointer(dpy, win, &root_return, &child_return,
+                  &dummyi, &dummyi, &dummyi, &dummyi, &dummyu);
+
+    return child_return;
+}
+
+/*
+ * Find client window at pointer location
+ *
+ * root   is the root window.
+ * subwin is the subwindow reported by a ButtonPress event on root.
+ *
+ * If the WM uses virtual roots subwin may be a virtual root.
+ * If so, we descend the window stack at the pointer location and assume the
+ * child is the client or one of its WM frame windows.
+ * This will of course work only if the virtual roots are children of the real
+ * root.
+ */
+Window
+Find_Client(Display * dpy, Window root, Window subwin)
+{
+    unsigned long *roots;
+    unsigned int i, n_roots;
+    Window win;
+
+    /* Check if subwin is a virtual root */
+    roots = Find_Roots(dpy, root, &n_roots);
+    for (i = 0; i < n_roots; i++) {
+        if (subwin != roots[i])
+            continue;
+        win = Find_Child_At_Pointer(dpy, subwin);
+        if (win == None)
+            return subwin;      /* No child - Return virtual root. */
+        subwin = win;
+        break;
+    }
+    if (roots)
+        XFree(roots);
+
+    if (atom_wm_state == None) {
+        atom_wm_state = XInternAtom(dpy, "WM_STATE", False);
+        if (!atom_wm_state)
+            return subwin;
+    }
+
+    /* Check if subwin has WM_STATE */
+    if (Window_Has_Property(dpy, subwin, atom_wm_state))
+        return subwin;
+
+    /* Attempt to find a client window in subwin's children */
+    win = Find_Client_In_Children(dpy, subwin);
+    if (win != None)
+        return win;             /* Found a client */
+
+    /* Did not find a client */
+    return subwin;
+}
diff --git a/clientwin.h b/clientwin.h
new file mode 100644
index 0000000..9fc59b5
--- /dev/null
+++ b/clientwin.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright 2007 Kim woelders
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission.  The copyright holders make no representations
+ * about the suitability of this software for any purpose.  It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+#ifndef _CLIENTWIN_H_
+#define _CLIENTWIN_H_
+
+#include <X11/Xlib.h>
+
+extern Window Find_Client(Display * dpy, Window root, Window target_win);
+
+#endif
diff --git a/configure.ac b/configure.ac
index 260dee4..2580530 100644
--- a/configure.ac
+++ b/configure.ac
@@ -33,7 +33,7 @@ AM_PROG_CC_C_O
 AC_PROG_INSTALL
 
 # Checks for pkg-config packages
-PKG_CHECK_MODULES(XWD, xmuu x11)
+PKG_CHECK_MODULES(XWD, x11)
 AC_SUBST(XWD_CFLAGS)
 AC_SUBST(XWD_LIBS)
 
diff --git a/dsimple.c b/dsimple.c
index c84ac3b..6fd77df 100644
--- a/dsimple.c
+++ b/dsimple.c
@@ -44,6 +44,7 @@ from The Open Group.
 #ifdef BUILD_PRINTSUPPORT
 #include <X11/XprintUtil/xprintutil.h>
 #endif /* BUILD_PRINTSUPPORT */
+#include "clientwin.h"
 #include "dsimple.h"
 
 /*
@@ -503,8 +504,7 @@ void blip()
  * Routine to let user select a window using the mouse
  */
 
-Window Select_Window(dpy)
-     Display *dpy;
+Window Select_Window(Display *dpy, int descend)
 {
   int status;
   Cursor cursor;
@@ -543,6 +543,11 @@ Window Select_Window(dpy)
 
   XUngrabPointer(dpy, CurrentTime);      /* Done with pointer */
 
+  if (!descend || (target_win == root))
+    return(target_win);
+
+  target_win = Find_Client(dpy, root, target_win);
+
   return(target_win);
 }
 
diff --git a/dsimple.h b/dsimple.h
index d4dbd01..d6b8d69 100644
--- a/dsimple.h
+++ b/dsimple.h
@@ -91,7 +91,7 @@ void usage(void);
 
 unsigned long Resolve_Color(Window, char *);
 Pixmap Bitmap_To_Pixmap(Display *, Drawable, GC, Pixmap, int, int);
-Window Select_Window(Display *);
+Window Select_Window(Display *, int);
 void blip(void);
 Window Window_With_Name(Display *, Window, char *);
 #ifdef __GNUC__
diff --git a/xwd.c b/xwd.c
index 82d43ef..944faab 100644
--- a/xwd.c
+++ b/xwd.c
@@ -74,7 +74,6 @@ in this Software without prior written authorization from The Open Group.
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 
-#include <X11/Xmu/WinUtil.h>
 typedef unsigned long Pixel;
 #include "X11/XWDFile.h"
 
@@ -199,22 +198,8 @@ main(argc, argv)
     /*
      * Let the user select the target window.
      */
-    if (!target_win) {
-	target_win = Select_Window(dpy);
-    }
-    
-    if (target_win != None && !frame_only) {
-        Window root;
-        int dummyi;
-        unsigned int dummy;
-
-        if (XGetGeometry (dpy, target_win, &root, &dummyi, &dummyi,
-			      &dummy, &dummy, &dummy, &dummy) &&
-                              target_win != root) {
-	      target_win = XmuClientWindow (dpy, target_win);
-	}
-    }
-
+    if (target_win == None)
+	target_win = Select_Window(dpy, !frame_only);
 
     /*
      * Dump it!