From ff7518c74dd5ae14e41910f713ecb194965b3f17 Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Fri, 24 Aug 2018 20:45:16 +0200 Subject: xgb-keys: minimal example of reading keys --- prototypes/xgb-keys.go | 213 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 213 insertions(+) create mode 100644 prototypes/xgb-keys.go (limited to 'prototypes') diff --git a/prototypes/xgb-keys.go b/prototypes/xgb-keys.go new file mode 100644 index 0000000..578ab39 --- /dev/null +++ b/prototypes/xgb-keys.go @@ -0,0 +1,213 @@ +package main + +import ( + "github.com/BurntSushi/xgb" + //"github.com/BurntSushi/xgb/xkb" + "github.com/BurntSushi/xgb/xproto" + "log" +) + +func main() { + X, err := xgb.NewConn() + if err != nil { + log.Fatalln(err) + } + + /* + // Use the extension if available, makes better use of state bits. + if err := xkb.Init(X); err == nil { + if _, err := xkb.UseExtension(X, 1, 0).Reply(); err != nil { + log.Fatalln(err) + } + } + */ + + setup := xproto.Setup(X) + screen := setup.DefaultScreen(X) + + visual, depth := screen.RootVisual, screen.RootDepth + // TODO: We should check that we find it, though we don't /need/ alpha here, + // it's just a minor improvement--affects the backpixel value. + for _, i := range screen.AllowedDepths { + for _, v := range i.Visuals { + // TODO: Could/should check other parameters. + if i.Depth == 32 && v.Class == xproto.VisualClassTrueColor { + visual, depth = v.VisualId, i.Depth + break + } + } + } + + mid, err := xproto.NewColormapId(X) + if err != nil { + log.Fatalln(err) + } + + _ = xproto.CreateColormap( + X, xproto.ColormapAllocNone, mid, screen.Root, visual) + + wid, err := xproto.NewWindowId(X) + if err != nil { + log.Fatalln(err) + } + + // Border pixel and colormap are required when depth differs from parent. + _ = xproto.CreateWindow(X, depth, wid, screen.Root, + 0, 0, 500, 500, 0, xproto.WindowClassInputOutput, + visual, xproto.CwBackPixel|xproto.CwBorderPixel|xproto.CwEventMask| + xproto.CwColormap, []uint32{0x80808080, 0, + xproto.EventMaskStructureNotify | xproto.EventMaskKeyPress | + /* KeymapNotify */ xproto.EventMaskKeymapState, uint32(mid)}) + + title := []byte("Keys") + _ = xproto.ChangeProperty(X, xproto.PropModeReplace, wid, xproto.AtomWmName, + xproto.AtomString, 8, uint32(len(title)), title) + + _ = xproto.MapWindow(X, wid) + + mapping, err := xproto.GetKeyboardMapping(X, setup.MinKeycode, + byte(setup.MaxKeycode-setup.MinKeycode+1)).Reply() + if err != nil { + log.Fatalln(err) + } + + // The order is "Shift, Lock, Control, Mod1, Mod2, Mod3, Mod4, and Mod5." + mm, err := xproto.GetModifierMapping(X).Reply() + if err != nil { + log.Fatalln(err) + } + + // XXX: This seems pointless, the key will just end up switching groups + // instead of levels without full XKB handling. Though perhaps it might + // at least work as intended when there's only one XKB group. + const MODE_SWITCH = 0xff7e + + var modeSwitchMask uint16 + for mod := 0; mod < 8; mod++ { + perMod := int(mm.KeycodesPerModifier) + for _, kc := range mm.Keycodes[mod*perMod : (mod+1)*perMod] { + if kc == 0 { + continue + } + + perKc := int(mapping.KeysymsPerKeycode) + k := int(kc - setup.MinKeycode) + for _, ks := range mapping.Keysyms[k*perKc : (k+1)*perKc] { + if ks == MODE_SWITCH { + modeSwitchMask |= 1 << uint(mod) + } + } + } + } + + for { + ev, xerr := X.WaitForEvent() + if xerr != nil { + log.Printf("Error: %s\n", xerr) + return + } + if ev == nil { + return + } + + log.Printf("Event: %s\n", ev) + switch e := ev.(type) { + case xproto.UnmapNotifyEvent: + return + + case xproto.KeymapNotifyEvent: + // e.Keys is a 32 * 8 large bitmap indicating which keys are + // currently pressed down. This is sent "after every EnterNotify + // and FocusIn" but it also seems to fire when the keyboard layout + // changes. aixterm manual even speaks of that explicitly. + // + // But since changing the effective group involves no changes to + // the compatibility mapping, there's nothing for us to do. + + case xproto.MappingNotifyEvent: + // e.FirstKeyCode .. e.Count changes have happened but rereading + // everything is the simpler thing to do. + mapping, err = xproto.GetKeyboardMapping(X, setup.MinKeycode, + byte(setup.MaxKeycode-setup.MinKeycode+1)).Reply() + if err != nil { + log.Fatalln(err) + } + + // TODO: We should also repeat the search for MODE SWITCH. + + case xproto.KeyPressEvent: + step := int(mapping.KeysymsPerKeycode) + from := int(e.Detail-setup.MinKeycode) * step + ks := mapping.Keysyms[from : from+step] + + // Strip trailing NoSymbol entries. + for len(ks) > 0 && ks[len(ks)-1] == 0 { + ks = ks[:len(ks)-1] + } + + // Expand back to at least 4. + switch { + case len(ks) == 1: + ks = append(ks, 0, ks[0], 0) + case len(ks) == 2: + ks = append(ks, ks[0], ks[1]) + case len(ks) == 3: + ks = append(ks, 0) + } + + // Other silly expansion rules, only applied to basic ASCII. + if ks[1] == 0 { + ks[1] = ks[0] + if ks[0] >= 'A' && ks[0] <= 'Z' || + ks[0] >= 'a' && ks[0] <= 'z' { + ks[0] = ks[0] | 32 + ks[1] = ks[0] &^ 32 + } + } + + if ks[3] == 0 { + ks[3] = ks[2] + if ks[2] >= 'A' && ks[2] <= 'Z' || + ks[2] >= 'a' && ks[2] <= 'z' { + ks[2] = ks[2] | 32 + ks[3] = ks[2] &^ 32 + } + } + + // We only have enough information to switch between two groups. + offset := 0 + if e.State&modeSwitchMask != 0 { + offset += 2 + } + + var result xproto.Keysym + + shift := e.State&xproto.ModMaskShift != 0 + lock := e.State&xproto.ModMaskLock != 0 + switch { + case !shift && !lock: + result = ks[offset+0] + case !shift && lock: + if ks[offset+0] >= 'a' && ks[offset+0] <= 'z' { + result = ks[offset+1] + } else { + result = ks[offset+0] + } + case shift && lock: + if ks[offset+1] >= 'a' && ks[offset+1] <= 'z' { + result = ks[offset+1] &^ 32 + } else { + result = ks[offset+1] + } + case shift: + result = ks[offset+1] + } + + if result <= 0xff { + log.Printf("%c (Latin-1)\n", rune(result)) + } else { + log.Println(result) + } + } + } +} -- cgit v1.2.3-70-g09d2