Add a -event parameter to control the event mask

It's annoying to have to sift through a lot of unrelated events if all you care
about is one specific class of events (e.g. RandR events).  Add a -event
parameter that can be used to tune which events to select.  When not specified,
all events are selected.

Change-Id: I36b0b36cc532d5e512d7469abd43a936afccbef5
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>
Reviewed-by: Andy Ritger <aritger@nvidia.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>

2 files changed, 103 insertions, 18 deletions

diff --git a/man/xev.man b/man/xev.man
index d13f022..ca38d56 100644
--- a/man/xev.man
+++ b/man/xev.man
@@ -52,6 +52,15 @@ This option specifies the name to assign to the created window.
 .TP 8
 .B \-rv
 This option specifies that the window should be in reverse video.
+.TP 8
+.B \-event \fIevent_mask\fP
+Select which events to display.
+The
+.B \-event
+option can be specified multiple times to select multiple types of events.
+When not specified, all events are selected.
+Available event masks: keyboard mouse expose visibility structure substructure
+focus property colormap owner_grab_button randr
 .SH "SEE ALSO"
 X(__miscmansuffix__), xwininfo(__appmansuffix__), xdpyinfo(__appmansuffix__), Xlib Programmers Manual, X Protocol
 Specification
diff --git a/xev.c b/xev.c
index 9f9111a..b130b2f 100644
--- a/xev.c
+++ b/xev.c
@@ -75,6 +75,12 @@ Atom wm_protocols;
 Bool have_rr;
 int rr_event_base, rr_error_base;
 
+enum EventMaskIndex {
+    EVENT_MASK_INDEX_CORE,
+    EVENT_MASK_INDEX_RANDR,
+    NUM_EVENT_MASKS
+};
+
 static void usage (void) _X_NORETURN;
 
 static void
@@ -878,6 +884,12 @@ usage (void)
 "    -s                                  set save-unders attribute",
 "    -name string                        window name",
 "    -rv                                 reverse video",
+"    -event event_mask                   select 'event_mask' events",
+"           Supported event masks: keyboard mouse expose visibility structure",
+"                                  substructure focus property colormap",
+"                                  owner_grab_button randr",
+"           This option can be specified multiple times to select multiple",
+"           event masks.",
 "",
 NULL};
     const char **cpp;
@@ -909,6 +921,66 @@ parse_backing_store (char *s)
     usage ();
 }
 
+static Bool
+parse_event_mask (const char *s, long event_masks[])
+{
+    const struct {
+        const char *name;
+        enum EventMaskIndex mask_index;
+        long mask;
+    } events[] = {
+        { "keyboard",
+          EVENT_MASK_INDEX_CORE,
+          KeyPressMask | KeyReleaseMask | KeymapStateMask },
+        { "mouse",
+          EVENT_MASK_INDEX_CORE,
+          ButtonPressMask | ButtonReleaseMask | EnterWindowMask |
+          LeaveWindowMask | PointerMotionMask | Button1MotionMask |
+          Button2MotionMask | Button3MotionMask | Button4MotionMask |
+          Button5MotionMask | ButtonMotionMask },
+        { "expose",
+          EVENT_MASK_INDEX_CORE,
+          ExposureMask },
+        { "visibility",
+          EVENT_MASK_INDEX_CORE,
+          VisibilityChangeMask },
+        { "structure",
+          EVENT_MASK_INDEX_CORE,
+          StructureNotifyMask },
+        { "substructure",
+          EVENT_MASK_INDEX_CORE,
+          SubstructureNotifyMask | SubstructureRedirectMask },
+        { "focus",
+          EVENT_MASK_INDEX_CORE,
+          FocusChangeMask },
+        { "property",
+          EVENT_MASK_INDEX_CORE,
+          PropertyChangeMask },
+        { "colormap",
+          EVENT_MASK_INDEX_CORE,
+          ColormapChangeMask },
+        { "owner_grab_button",
+          EVENT_MASK_INDEX_CORE,
+          OwnerGrabButtonMask },
+        { "randr",
+          EVENT_MASK_INDEX_RANDR,
+          RRScreenChangeNotifyMask | RRCrtcChangeNotifyMask |
+          RROutputChangeNotifyMask | RROutputPropertyNotifyMask },
+        { NULL, 0, 0 }
+    };
+    int i;
+
+    for (i = 0; events[i].name; i++) {
+        if (!s || !strcmp(s, events[i].name)) {
+            event_masks[events[i].mask_index] |= events[i].mask;
+            if (s)
+                return True;
+        }
+    }
+
+    return False;
+}
+
 int
 main (int argc, char **argv)
 {
@@ -931,6 +1003,8 @@ main (int argc, char **argv)
     XIMStyle xim_style = 0;
     char *modifiers;
     char *imvalret;
+    long event_masks[NUM_EVENT_MASKS];
+    Bool event_mask_specified = False;
 
     ProgramName = argv[0];
 
@@ -939,6 +1013,8 @@ main (int argc, char **argv)
 		ProgramName);
     }
 
+    memset(event_masks, 0, sizeof(event_masks));
+
     w = 0;
     for (i = 1; i < argc; i++) {
 	char *arg = argv[i];
@@ -995,6 +1071,12 @@ main (int argc, char **argv)
 		attr.save_under = True;
 		mask |= CWSaveUnder;
 		continue;
+	      case 'e':			/* -event */
+		if (++i >= argc) usage ();
+		if (!parse_event_mask (argv[i], event_masks))
+		    usage ();
+		event_mask_specified = True;
+		continue;
 	      default:
 		usage ();
 	    }				/* end switch on - */
@@ -1002,6 +1084,10 @@ main (int argc, char **argv)
 	  usage ();
     }					/* end for over argc */
 
+    /* if no -event options were specified, pretend all of them were */
+    if (!event_mask_specified)
+        parse_event_mask (NULL, event_masks);
+
     dpy = XOpenDisplay (displayname);
     if (!dpy) {
 	fprintf (stderr, "%s:  unable to open display '%s'\n",
@@ -1046,19 +1132,7 @@ main (int argc, char **argv)
 
     screen = DefaultScreen (dpy);
 
-    /* select for all events */
-    attr.event_mask = KeyPressMask | KeyReleaseMask | ButtonPressMask |
-			   ButtonReleaseMask | EnterWindowMask |
-			   LeaveWindowMask | PointerMotionMask |
-			   Button1MotionMask |
-			   Button2MotionMask | Button3MotionMask |
-			   Button4MotionMask | Button5MotionMask |
-			   ButtonMotionMask | KeymapStateMask |
-			   ExposureMask | VisibilityChangeMask |
-			   StructureNotifyMask | /* ResizeRedirectMask | */
-			   SubstructureNotifyMask | SubstructureRedirectMask |
-			   FocusChangeMask | PropertyChangeMask |
-			   ColormapChangeMask | OwnerGrabButtonMask;
+    attr.event_mask = event_masks[EVENT_MASK_INDEX_CORE];
 
     if (use_root)
 	w = RootWindow(dpy, screen);
@@ -1126,12 +1200,14 @@ main (int argc, char **argv)
         int rr_major, rr_minor;
 
         if (XRRQueryVersion (dpy, &rr_major, &rr_minor)) {
-            int rr_mask = RRScreenChangeNotifyMask;
+            int rr_mask = event_masks[EVENT_MASK_INDEX_RANDR];
+
+            if (rr_major == 1 && rr_minor <= 1) {
+                rr_mask &= ~(RRCrtcChangeNotifyMask |
+                             RROutputChangeNotifyMask |
+                             RROutputPropertyNotifyMask);
+            }
 
-            if (rr_major > 1
-                || (rr_major == 1 && rr_minor >= 2))
-                rr_mask |= RRCrtcChangeNotifyMask | RROutputChangeNotifyMask |
-                           RROutputPropertyNotifyMask;
             XRRSelectInput (dpy, w, rr_mask);
         }
     }