i3 - improved tiling WM


Respect Motif hint for window decorations

Patch status: needinfo

Patch by Tony Crisci

Long description:

When the _MOTIF_WM_HINTS property of a window specifies it should have
no title bar, or no decorations at all, respond by setting the border
style of that container to BS_PIXEL or BS_NONE respectively.

This comes from the old Motif window manager. It was originally intended
to specify exactly what sort of decorations a window should have, and
exactly what sort of user input it should respond to. The EWMH spec
intended to replace Motif hints with _NET_WM_WINDOW_TYPE, but it is
still in use by popular widget toolkits such as GTK+ and Java AWT.

i3's implementation simply mirrors Gnome's Metacity. Official
documentation of this hint is nowhere to be found.

For more information see:
https://people.gnome.org/~tthurman/docs/metacity/xprops_8h-source.html
http://stackoverflow.com/questions/13787553/detect-if-a-x11-window-has-decorations

fixes #832

To apply this patch, use:
curl http://cr.i3wm.org/patch/373/raw.patch | git am

b/include/atoms.xmacro

34
@@ -31,3 +31,4 @@ xmacro(I3_SHMLOG_PATH)
35
 xmacro(I3_PID)
36
 xmacro(_NET_REQUEST_FRAME_EXTENTS)
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 xmacro(_NET_FRAME_EXTENTS)
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+xmacro(_MOTIF_WM_HINTS)

b/include/window.h

43
@@ -61,3 +61,17 @@ void window_update_role(i3Window *win, xcb_get_property_reply_t *prop, bool befo
44
  *
45
  */
46
 void window_update_hints(i3Window *win, xcb_get_property_reply_t *prop, bool *urgency_hint);
47
+
48
+/**
49
+ * Updates the MOTIF_WM_HINTS. The container's border style should be set to
50
+ * `motif_border_style' if border style is not BS_NORMAL.
51
+ *
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+ * i3 only uses this hint when it specifies a window should have no
53
+ * title bar, or no decorations at all, which is how most window managers
54
+ * handle it.
55
+ *
56
+ * The EWMH spec intended to replace Motif hints with _NET_WM_WINDOW_TYPE, but
57
+ * it is still in use by popular widget toolkits such as GTK+ and Java AWT.
58
+ *
59
+ */
60
+void window_update_motif_hints(i3Window *win, xcb_get_property_reply_t *prop, border_style_t *motif_border_style);

b/src/manage.c

65
@@ -118,7 +118,8 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
66
     xcb_get_property_cookie_t wm_type_cookie, strut_cookie, state_cookie,
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                               utf8_title_cookie, title_cookie,
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                               class_cookie, leader_cookie, transient_cookie,
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-                              role_cookie, startup_id_cookie, wm_hints_cookie;
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+                              role_cookie, startup_id_cookie, wm_hints_cookie,
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+                              motif_wm_hints_cookie;
72
 
73
 
74
     geomc = xcb_get_geometry(conn, d);
75
@@ -188,6 +189,7 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
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     role_cookie = GET_PROPERTY(A_WM_WINDOW_ROLE, 128);
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     startup_id_cookie = GET_PROPERTY(A__NET_STARTUP_ID, 512);
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     wm_hints_cookie = xcb_icccm_get_wm_hints(conn, window);
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+    motif_wm_hints_cookie = GET_PROPERTY(A__MOTIF_WM_HINTS, 5 * sizeof(long));
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     /* TODO: also get wm_normal_hints here. implement after we got rid of xcb-event */
81
 
82
     DLOG("Managing window 0x%08x\n", window);
83
@@ -222,6 +224,8 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
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     window_update_role(cwindow, xcb_get_property_reply(conn, role_cookie, NULL), true);
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     bool urgency_hint;
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     window_update_hints(cwindow, xcb_get_property_reply(conn, wm_hints_cookie, NULL), &urgency_hint);
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+    border_style_t motif_border_style = BS_NORMAL;
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+    window_update_motif_hints(cwindow, xcb_get_property_reply(conn, motif_wm_hints_cookie, NULL), &motif_border_style);
89
 
90
     xcb_get_property_reply_t *startup_id_reply;
91
     startup_id_reply = xcb_get_property_reply(conn, startup_id_cookie, NULL);
92
@@ -439,6 +443,16 @@ void manage_window(xcb_window_t window, xcb_get_window_attributes_cookie_t cooki
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      * here because it’s used for dock clients. */
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     nc->geometry = (Rect){ geom->x, geom->y, geom->width, geom->height };
95
 
96
+    if (motif_border_style != BS_NORMAL) {
97
+        DLOG("MOTIF_WM_HINTS specifies decorations (border_style = %d)\n", motif_border_style);
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+        /* A client sets these hints because they are providing their own
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+         * window controls (Chromium, Steam), splash screens, or shaped utility
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+         * windows that need focus (Eclipse), so it makes sense to make them
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+         * floating. */
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+        floating_enable(nc, false);
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+        con_set_border_style(nc, motif_border_style, config.default_border_width);
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+    }
105
+
106
     if (want_floating) {
107
         DLOG("geometry = %d x %d\n", nc->geometry.width, nc->geometry.height);
108
         floating_enable(nc, true);

b/src/window.c

113
@@ -254,3 +254,59 @@ void window_update_hints(i3Window *win, xcb_get_property_reply_t *prop, bool *ur
114
 
115
     free(prop);
116
 }
117
+
118
+/*
119
+ * Updates the MOTIF_WM_HINTS. The container's border style should be set to
120
+ * `motif_border_style' if border style is not BS_NORMAL.
121
+ *
122
+ * i3 only uses this hint when it specifies a window should have no
123
+ * title bar, or no decorations at all, which is how most window managers
124
+ * handle it.
125
+ *
126
+ * The EWMH spec intended to replace Motif hints with _NET_WM_WINDOW_TYPE, but
127
+ * it is still in use by popular widget toolkits such as GTK+ and Java AWT.
128
+ *
129
+ */
130
+void window_update_motif_hints(i3Window *win, xcb_get_property_reply_t *prop, border_style_t *motif_border_style) {
131
+    /* This implementation simply mirrors Gnome's Metacity. Official
132
+     * documentation of this hint is nowhere to be found.
133
+     * For more information see:
134
+     * https://people.gnome.org/~tthurman/docs/metacity/xprops_8h-source.html
135
+     * http://stackoverflow.com/questions/13787553/detect-if-a-x11-window-has-decorations
136
+     */
137
+#define MWM_HINTS_DECORATIONS   (1L << 1)
138
+#define MWM_DECOR_ALL           (1L << 0)
139
+#define MWM_DECOR_BORDER        (1L << 1)
140
+#define MWM_DECOR_TITLE         (1L << 3)
141
+
142
+    if (motif_border_style != NULL)
143
+        *motif_border_style = BS_NORMAL;
144
+
145
+    if (prop == NULL || xcb_get_property_value_length(prop) == 0) {
146
+        FREE(prop);
147
+        return;
148
+    }
149
+
150
+    /* The property consists of an array of 5 `long's. The first value is a bit
151
+     * mask of what properties the hint will specify. We are only interested in
152
+     * MWM_HINTS_DECORATIONS because it indicates that the second value of the
153
+     * array tells us which decorations the window should have, each flag being
154
+     * a particular decoration. */
155
+    long *motif_hints = (long *)xcb_get_property_value(prop);
156
+
157
+    if (motif_border_style != NULL && motif_hints[0] & MWM_HINTS_DECORATIONS) {
158
+        if (motif_hints[1] & MWM_DECOR_ALL || motif_hints[1] & MWM_DECOR_TITLE)
159
+            *motif_border_style = BS_NORMAL;
160
+        else if (motif_hints[1] & MWM_DECOR_BORDER)
161
+            *motif_border_style = BS_PIXEL;
162
+        else
163
+            *motif_border_style = BS_NONE;
164
+    }
165
+
166
+    FREE(prop);
167
+
168
+#undef MWM_HINTS_DECORATIONS
169
+#undef MWM_DECOR_ALL
170
+#undef MWM_DECOR_BORDER
171
+#undef MWM_DECOR_TITLE
172
+}