Initial

Author: eddy

makefile

@@ -0,0 +1,17 @@
+LDFLAGS += -lX11
+CXXFLAGS += -Wall
+
+SRC=wintag.cpp
+OBJS=$(patsubst %.cpp,%.o,$(SRC))
+BINARY=wintag
+
+%.o: %.cpp
+	g++ $(CXXFLAGS) -c -o $@ $<
+
+$(BINARY): $(OBJS)
+	g++ $(LDFLAGS) -o $@ $^
+
+clean:
+	rm -rf $(OBJS) $(BINARY)
+
+.PHONY: clean

wintag.cpp

@@ -0,0 +1,131 @@
+/* TODO:
+ *      per screen context
+ *      root window change event handling (regrab keys)
+ *      systray icon
+ */
+
+#include <map>
+#include <stdio.h>
+#include <X11/Xlib.h>
+#include <X11/Xatom.h>
+
+Atom active_window_atom(Display *display) {
+    return XInternAtom(display, "_NET_ACTIVE_WINDOW", True);
+}
+
+struct XBuffer {
+    unsigned char* mem;
+    int format;
+    unsigned long items;
+
+    XBuffer(): mem(0), format(0), items(0) {}
+
+    ~XBuffer() {
+        if (mem) { XFree(mem); }
+    }
+};
+
+struct XDisplay {
+    Display *display;
+    XDisplay(const char *name) {
+        display = XOpenDisplay(name);
+    }
+    ~XDisplay() {
+        XCloseDisplay(display);
+    }
+    operator Display* () {
+        return display;
+    }
+};
+
+int get_window_property(Display *display, Window window, Atom property, Atom type, int format, unsigned size, XBuffer& buffer/* result */) {
+    Atom ret_type;
+    unsigned long bytes_after;
+
+    int r = XGetWindowProperty(display, window, property, 0, size, False, XA_WINDOW,
+                               &ret_type, &buffer.format, &buffer.items, &bytes_after, &buffer.mem);
+
+    if (r != Success)            { printf("XGetWindowProperty failed"); return 1; }
+    if (ret_type != type)        { printf("XGetWindowProperty: ret type mismatch: %lu\n", ret_type); return 1; }
+    if (format != buffer.format) { printf("XGetWindowProperty: format mismatch: %d\n", format); return 1; }
+    if (buffer.items < size)     { printf("XGetWindowProperty: bad item size: %d\n", format); return 1; }
+
+    return 0;
+}
+
+Window get_active_window(Display *display, Window root) {
+    XBuffer result;
+    if (get_window_property(display, root, active_window_atom(display), XA_WINDOW, 32, 1, result) != 0) { return 0; }
+    
+    return *(Window*) result.mem;
+}
+
+typedef std::map<unsigned int, Window> KeyToWindowMap;
+
+void map_hotkeys(Display *display, Window root, KeyToWindowMap& map, unsigned int modifiers, const char* keys[]) {
+    for (int i = 0; keys[i] != 0; ++i) {
+        KeyCode key = XKeysymToKeycode(display, XStringToKeysym(keys[i]));
+        XGrabKey(display, key, modifiers, root, True, GrabModeSync, GrabModeSync);
+        map[key] = 0;
+    }
+}
+
+void activate_window(Display *display, Window root, Window active_window) {
+    XEvent ev;
+    ev.type = ClientMessage;
+    ev.xclient.display = display;
+    ev.xclient.window = active_window;
+    ev.xclient.message_type = active_window_atom(display);
+    ev.xclient.format = 32;
+    ev.xclient.data.l[0] = 2; // pager message source
+    ev.xclient.data.l[1] = CurrentTime;
+    XSendEvent(display, root, False, SubstructureNotifyMask | SubstructureRedirectMask, &ev);
+}
+
+#define AltKeyMask Mod1Mask
+#define WinKeyMask Mod4Mask
+
+#define SelectKeyMask   WinKeyMask
+#define SetKeyMask      (WinKeyMask | AltKeyMask)
+
+int main() {
+    XDisplay display = XDisplay("");
+    Window root = XDefaultRootWindow(display);
+
+    KeyToWindowMap hotkeys;
+    const char* keys[] = { "1", "2", "3", "4", "5", "6", "7", "8", "9", 0 };
+    map_hotkeys(display, root, hotkeys, SelectKeyMask, keys);
+    map_hotkeys(display, root, hotkeys, SetKeyMask, keys);
+    
+    XEvent ev;
+    for(;;) {
+        XNextEvent(display, &ev);
+        if (ev.type == KeyPress || ev.type == KeyRelease) {
+            //printf("Key event: code=%p mod=%p set=%p select=%p\n", ev.xkey.keycode, ev.xkey.state, SetKeyMask, SelectKeyMask);
+            KeyToWindowMap::iterator it = hotkeys.find(ev.xkey.keycode);
+            if (it != hotkeys.end() && ((ev.xkey.state == SetKeyMask) || (ev.xkey.state == SelectKeyMask))) {
+                // do job
+                if(ev.type == KeyPress) {
+                    if (ev.xkey.state == SelectKeyMask) {
+                        if (it->second != 0) {
+                            printf("Bringing up active window: %lu\n", it->second);
+                            activate_window(display, root, it->second);
+                        } else {
+                            printf("No active window\n");
+                        }
+                    } else if (ev.xkey.state == SetKeyMask) {
+                        it->second = get_active_window(display, root);
+                        printf("Remembering active window: %lu\n", it->second);
+                    }
+                }
+                XAllowEvents(display, AsyncKeyboard, ev.xkey.time);
+            } else {
+                //let key go
+                XAllowEvents(display, ReplayKeyboard, ev.xkey.time);
+            }
+            XFlush(display);
+        }
+    }
+
+    return 0;
+}