Merge pull request #46 from mbattista/multiple-keys

pressing key with multiple pressed keys

server/internal/remote/manager.go

@@ -245,14 +245,7 @@ func (manager *RemoteManager) GetScreenSize() *types.ScreenSize {
 }
 
 func (manager *RemoteManager) SetKeyboardLayout(layout string) {
-	// Workaround for https://github.com/m1k1o/neko/issues/45
+	exec.Command("setxkbmap", layout).Run()
-	// When pressing `shift` + `,` instead of `<` comes `>`.
-	variant := ""
-	if layout == "us" {
-		variant = "mac" // TODO: Test all keys.
-	}
-
-	exec.Command("setxkbmap", layout, variant).Run()
 }
 
 func (manager *RemoteManager) SetKeyboardModifiers(NumLock int, CapsLock int, ScrollLock int) {

server/internal/xorg/xorg.c

@@ -6,6 +6,48 @@ static char *NAME = ":0.0";
 static int REGISTERED = 0;
 static int DIRTY = 0;
 
+xkeys_t *xKeysHead = NULL;
+
+void XKeysInsert(KeySym keysym, KeyCode keycode) {
+  xkeys_t *node = (xkeys_t *) malloc(sizeof(xkeys_t));
+
+  node->keysym = keysym;
+  node->keycode = keycode;
+  node->next = xKeysHead;
+  xKeysHead = node;
+}
+
+KeyCode XKeysPop(KeySym keysym) {
+  KeyCode keycode = 0;
+  xkeys_t *node = xKeysHead,
+          *previous = NULL;
+  int i = 0;
+
+  while (node) {
+    if (node->keysym == keysym) {
+      keycode = node->keycode;
+
+      if (!previous)
+        xKeysHead = node->next;
+      else
+        previous->next = node->next;
+
+      free(node);
+      return keycode;
+    }
+
+    previous = node;
+    node = node->next;
+    if (i++ > 120) {
+      // this should NEVER HAPPEN
+      fprintf(stderr, "[FATAL-ERROR] XKeysPop() in xorg.c: reached maximum loop limit! Something is wrong\n");
+      break;
+    }
+  }
+
+  return 0;
+}
+
 Display *getXDisplay(void) {
   /* Close the display if displayName has changed */
   if (DIRTY) {
@@ -23,7 +65,7 @@ Display *getXDisplay(void) {
     }
 
     if (DISPLAY == NULL) {
-      fputs("Could not open main display\n", stderr);
+      fprintf(stderr, "[FATAL-ERROR] XKeysPop() in xorg.c: Could not open main display!");
     } else if (!REGISTERED) {
       atexit(&XDisplayClose);
       REGISTERED = 1;
@@ -96,26 +138,74 @@ void XButton(unsigned int button, int down) {
   }
 }
 
-void XKey(unsigned long key, int down) {
+// From: https://github.com/TigerVNC/tigervnc/blob/0946e298075f8f7b6d63e552297a787c5f84d27c/unix/x0vncserver/XDesktop.cxx#L343-L379
-  if (key != 0) {
+KeyCode XkbKeysymToKeycode(Display *dpy, KeySym keysym) {
-    Display *display = getXDisplay();
+  XkbDescPtr xkb;
-    KeyCode code = XKeysymToKeycode(display, key);
+  XkbStateRec state;
+  unsigned int mods;
+  unsigned keycode;
 
-    // Map non-existing keysyms to new keycodes
+  xkb = XkbGetMap(dpy, XkbAllComponentsMask, XkbUseCoreKbd);
-    if(code == 0) {
+  if (!xkb)
-      int min, max, numcodes;
+    return 0;
-      XDisplayKeycodes(display, &min, &max);
-      XGetKeyboardMapping(display, min, max-min, &numcodes);
 
-      code = (max-min+1)*numcodes;
+  XkbGetState(dpy, XkbUseCoreKbd, &state);
-      KeySym keysym_list[numcodes];
+  // XkbStateFieldFromRec() doesn't work properly because
-      for(int i=0;i<numcodes;i++) keysym_list[i] = key;
+  // state.lookup_mods isn't properly updated, so we do this manually
-      XChangeKeyboardMapping(display, code, numcodes, keysym_list, 1);
+  mods = XkbBuildCoreState(XkbStateMods(&state), state.group);
-    }
 
-    XTestFakeKeyEvent(display, code, down, CurrentTime);
+  for (keycode = xkb->min_key_code;
-    XSync(display, 0);
+       keycode <= xkb->max_key_code;
+       keycode++) {
+    KeySym cursym;
+    unsigned int out_mods;
+    XkbTranslateKeyCode(xkb, keycode, mods, &out_mods, &cursym);
+    if (cursym == keysym)
+      break;
   }
+
+  if (keycode > xkb->max_key_code)
+    keycode = 0;
+
+  XkbFreeKeyboard(xkb, XkbAllComponentsMask, True);
+
+  // Shift+Tab is usually ISO_Left_Tab, but RFB hides this fact. Do
+  // another attempt if we failed the initial lookup
+  if ((keycode == 0) && (keysym == XK_Tab) && (mods & ShiftMask))
+    return XkbKeysymToKeycode(dpy, XK_ISO_Left_Tab);
+
+  return keycode;
+}
+
+void XKey(KeySym key, int down) {
+  Display *display = getXDisplay();
+  KeyCode code = 0;
+
+  if (!down)
+    code = XKeysPop(key);
+
+  if (!code)
+    code = XkbKeysymToKeycode(display, key);
+
+  if (!code) {
+    int min, max, numcodes;
+    XDisplayKeycodes(display, &min, &max);
+    XGetKeyboardMapping(display, min, max-min, &numcodes);
+
+    code = (max-min+1)*numcodes;
+    KeySym keysym_list[numcodes];
+    for (int i=0;i<numcodes;i++) keysym_list[i] = key;
+    XChangeKeyboardMapping(display, code, numcodes, keysym_list, 1);
+  }
+
+  if (!code)
+    return;
+
+  if (down)
+    XKeysInsert(key, code);
+
+  XTestFakeKeyEvent(display, code, down, CurrentTime);
+  XSync(display, 0);
 }
 
 void XClipboardSet(char *src) {

server/internal/xorg/xorg.go

@@ -75,7 +75,7 @@ func KeyDown(code uint64) error {
 
 	debounce_key[code] = time.Now()
 
-	C.XKey(C.ulong(code), C.int(1))
+	C.XKey(C.KeySym(code), C.int(1))
 	return nil
 }
 
@@ -103,7 +103,7 @@ func KeyUp(code uint64) error {
 
 	delete(debounce_key, code)
 
-	C.XKey(C.ulong(code), C.int(0))
+	C.XKey(C.KeySym(code), C.int(0))
 	return nil
 }
 

server/internal/xorg/xorg.h

@@ -16,6 +16,12 @@
   extern void goCreateScreenSize(int index, int width, int height, int mwidth, int mheight);
   extern void goSetScreenRates(int index, int rate_index, short rate);
 
+  typedef struct xkeys_t {
+    KeySym keysym;
+    KeyCode keycode;
+    struct xkeys_t *next;
+  } xkeys_t;
+
   /* Returns the main display, closed either on exit or when closeMainDisplay()
   * is invoked. This removes a bit of the overhead of calling XOpenDisplay() &
   * XCloseDisplay() everytime the main display needs to be used.