code review 159050044: taowm: exec setxkbmap to clear Caps Lock, instead of do... (issue 159050044 by nigeltao@golang.org)

[nige...@golang.org]

Reviewers: nigeltao,

Message:
Hello nigeltao, nige...@golang.org (cc: ta...@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/taowm/


Description:
taowm: exec setxkbmap to clear Caps Lock, instead of doing the
equivalent of what xmodmap does. The latter worked for Ubuntu 12.04
but does not seem to work on Ubuntu 14.04.

Please review this at https://codereview.appspot.com/159050044/

Affected files (+10, -49 lines):
M taowm/xinit.go


Index: taowm/xinit.go
===================================================================
--- a/taowm/xinit.go
+++ b/taowm/xinit.go
@@ -3,6 +3,7 @@
import (
"bytes"
"log"
+ "os/exec"

"github.com/BurntSushi/xgb/xinerama"
xp "github.com/BurntSushi/xgb/xproto"
@@ -178,55 +179,15 @@

// Disable Caps Lock if it is the wmKeysym.
if wmKeysym == xkCapsLock {
- // First, remap the Caps_Lock key code to Hyper_R.
- // This is the equivalent of: xmodmap -e "keysym Caps_Lock = Hyper_R".
- i0 := int(wmKeycode-keyLo+0) * n
- i1 := int(wmKeycode-keyLo+1) * n
- newKeysyms := make([]xp.Keysym, n)
- copy(newKeysyms, km.Keysyms[i0:i1])
- for i := range newKeysyms {
- if newKeysyms[i] == xkCapsLock {
- newKeysyms[i] = xkHyperR
- }
- }
- if err := xp.ChangeKeyboardMappingChecked(xConn,
- 1, wmKeycode, uint8(n), newKeysyms).Check(); err != nil {
- log.Fatal(err)
- }
-
- // Second, clear the lock modifier mapping.
- // This is the equivalent of: xmodmap -e "clear lock".
- mm, err := xp.GetModifierMapping(xConn).Reply()
- if err != nil {
- log.Fatal(err)
- }
- masks := [...]int{
- xp.ModMaskShift,
- xp.ModMaskLock,
- xp.ModMaskControl,
- xp.ModMask1,
- xp.ModMask2,
- xp.ModMask3,
- xp.ModMask4,
- xp.ModMask5,
- }
- for i, mask := range masks {
- if len(mm.Keycodes) < (i+1)*int(mm.KeycodesPerModifier) {
- break
- }
- if mask == xp.ModMaskLock {
- for j := 0; j < int(mm.KeycodesPerModifier); j++ {
- mm.Keycodes[i*int(mm.KeycodesPerModifier)+j] = 0
- }
- break
- }
- }
- sm, err := xp.SetModifierMapping(xConn, mm.KeycodesPerModifier,
mm.Keycodes).Reply()
- if err != nil {
- log.Fatal(err)
- }
- if sm.Status != xp.MappingStatusSuccess {
- log.Fatal("could not set modifier mapping")
+ // On Ubuntu 12.04, disabling Caps Lock involved the equivalent of
+ // `xmodmap -e "clear lock"`. On Ubuntu 14.04, XKB has replaced xmodmap,
+ // possibly because this facilitates per-window keyboard layouts, so the
+ // equivalent of `xmodmap -e "clear lock"` doesn't work. As of October
+ // 2014, github.com/BurntSushi/xgb doesn't support XKB, so we exec the
+ // setxkbmap program instead of speaking the X11 protocol directly to
+ // disable Caps Lock.
+ if err := exec.Command("setxkbmap", "-option", "caps:none").Run();
err != nil {
+ log.Fatalf("setxkbmap failed: %v", err)
}
}
}

[nige...@golang.org]

*** Submitted as
https://code.google.com/p/taowm/source/detail?r=758502b4d748 ***

taowm: exec setxkbmap to clear Caps Lock, instead of doing the
equivalent of what xmodmap does. The latter worked for Ubuntu 12.04
but does not seem to work on Ubuntu 14.04.

TBR=nigeltao
R=nigeltao
CC=taowm
https://codereview.appspot.com/159050044


https://codereview.appspot.com/159050044/