Added Keyboard Layout Indicator Plugin

4 files changed, 436 insertions, 6 deletions

diff --git a/README b/README
index 7acb0c8..54d0720 100644
--- a/README
+++ b/README
@@ -683,6 +683,8 @@ Monitors have default aliases.
   distribution can be used to set the given property from the output
   of any other program or script.
 
+[samples/xmonadpropwrite.hs script]: https://github.com/jaor/xmobar/raw/master/samples/xmonadpropwrite.hs
+
 `Brightness Args RefreshRate`
 
 - Aliases to `bright`
@@ -700,8 +702,19 @@ Monitors have default aliases.
 
        Run Brightness ["-t", "<bar>"] 60
 
+`Kbd Opts`
+
+- Registers to XKB/X11-Events and output the currently active keyboard layout.
+  Supports replacement of layoutnames.
+- Aliases to `kbd`
+- Opts
+	- `-e`: String displayed on an error while accessing X (default: "Err")
+	- `-s`: Search string, can be used multiple times (optional)
+	- `-r`: Replacement string, one for every Search should be given (optional)
+- Example:
+
+		Run Kbd [] ["-s", "us(dvorak)", "-r", "DV", "-s", "us", "-r", "US"] "kbd"
 
-[samples/xmonadpropwrite.hs script]: https://github.com/jaor/xmobar/raw/master/samples/xmonadpropwrite.hs
 
 ## Monitor Plugins Commands Arguments
 
diff --git a/src/Config.hs b/src/Config.hs
index 3184023..4405314 100644
--- a/src/Config.hs
+++ b/src/Config.hs
@@ -32,6 +32,7 @@ import Plugins.CommandReader
 import Plugins.StdinReader
 import Plugins.XMonadLog
 import Plugins.EWMH
+import Plugins.Kbd
 
 #ifdef INOTIFY
 import Plugins.Mail
@@ -112,7 +113,7 @@ infixr :*:
 -- the 'Runnable.Runnable' Read instance. To install a plugin just add
 -- the plugin's type to the list of types (separated by ':*:') appearing in
 -- this function's type signature.
-runnableTypes :: Command :*: Monitors :*: Date :*: PipeReader :*: CommandReader :*: StdinReader :*: XMonadLog :*: EWMH :*:
+runnableTypes :: Command :*: Monitors :*: Date :*: PipeReader :*: CommandReader :*: StdinReader :*: XMonadLog :*: EWMH :*: Kbd :*:
 #ifdef INOTIFY
                  Mail :*: MBox :*:
 #endif
diff --git a/src/Plugins/Kbd.hsc b/src/Plugins/Kbd.hsc
new file mode 100644
index 0000000..8e87af6
--- /dev/null
+++ b/src/Plugins/Kbd.hsc
@@ -0,0 +1,415 @@
+{-# LANGUAGE ScopedTypeVariables, ForeignFunctionInterface, MultiParamTypeClasses, DeriveDataTypeable, FlexibleInstances, PatternGuards #-}
+
+module Plugins.Kbd where
+
+import Graphics.X11.Xlib
+import Graphics.X11.Xlib.Extras
+import Foreign
+import Foreign.C.Types (CUInt,CULong,CInt,CUShort,CChar,CUChar)
+import Foreign.C.String
+import Plugins
+import Control.Monad (forever)
+import XUtil (nextEvent')
+import Data.List (isPrefixOf, elemIndex)
+import Data.Maybe (fromJust)
+import System.Console.GetOpt
+
+#include <X11/XKBlib.h>
+#include <X11/extensions/XKB.h>
+#include <X11/extensions/XKBstr.h>
+
+-- 
+-- Definition for XkbStaceRec and getKbdLayout taken from
+-- XMonad.Layout.XKBLayout
+--
+data XkbStateRec = XkbStateRec {
+    group :: CUChar,
+    locked_group :: CUChar,
+    base_group :: CUShort,
+    latched_group :: CUShort,
+    mods :: CUChar,
+    base_mods :: CUChar,
+    latched_mods :: CUChar,
+    locked_mods :: CUChar,
+    compat_state :: CUChar,
+    grab_mods :: CUChar,
+    compat_grab_mods :: CUChar,
+    lookup_mods :: CUChar,
+    compat_lookup_mods :: CUChar,
+    ptr_buttons :: CUShort
+}
+
+instance Storable XkbStateRec where
+    sizeOf _ = (#size XkbStateRec)
+    alignment _ = alignment (undefined :: CUShort)
+    peek ptr = do
+        r_group <- (#peek XkbStateRec, group) ptr
+        r_locked_group <- (#peek XkbStateRec, locked_group) ptr
+        r_base_group <- (#peek XkbStateRec, base_group) ptr
+        r_latched_group <- (#peek XkbStateRec, latched_group) ptr
+        r_mods <- (#peek XkbStateRec, mods) ptr
+        r_base_mods <- (#peek XkbStateRec, base_mods) ptr
+        r_latched_mods <- (#peek XkbStateRec, latched_mods) ptr
+        r_locked_mods <- (#peek XkbStateRec, locked_mods) ptr
+        r_compat_state <- (#peek XkbStateRec, compat_state) ptr
+        r_grab_mods <- (#peek XkbStateRec, grab_mods) ptr
+        r_compat_grab_mods <- (#peek XkbStateRec, compat_grab_mods) ptr
+        r_lookup_mods <- (#peek XkbStateRec, lookup_mods) ptr
+        r_compat_lookup_mods <- (#peek XkbStateRec, compat_lookup_mods) ptr
+        r_ptr_buttons <- (#peek XkbStateRec, ptr_buttons) ptr
+        return XkbStateRec {
+            group = r_group,
+            locked_group = r_locked_group,
+            base_group = r_base_group,
+            latched_group = r_latched_group,
+            mods = r_mods,
+            base_mods = r_base_mods,
+            latched_mods = r_latched_mods,
+            locked_mods = r_locked_mods,
+            compat_state = r_compat_state,
+            grab_mods = r_grab_mods,
+            compat_grab_mods = r_compat_grab_mods,
+            lookup_mods = r_lookup_mods,
+            compat_lookup_mods = r_compat_lookup_mods,
+            ptr_buttons = r_ptr_buttons
+        }
+
+foreign import ccall unsafe "X11/XKBlib.h XkbGetState"
+    xkbGetState :: Display -> CUInt -> Ptr XkbStateRec -> IO CInt
+
+
+getKbdLayout :: Display -> IO Int
+getKbdLayout d = alloca $ \stRecPtr -> do
+    xkbGetState d 0x100 stRecPtr
+    st <- peek stRecPtr
+    return $ fromIntegral (group st)
+
+--
+--
+--
+
+data XkbKeyNameRec = XkbKeyNameRec {
+	name :: Ptr CChar -- array
+}
+
+--
+-- the t_ before alias is just because of name collisions
+--
+data XkbKeyAliasRec = XkbKeyAliasRec {
+	real  :: Ptr CChar, -- array
+	t_alias :: Ptr CChar  -- array
+} 
+
+--
+-- the t_ before geometry is just because of name collisions
+--
+data XkbNamesRec = XkbNamesRec {
+    keycodes :: Atom,
+    t_geometry :: Atom,
+    symbols :: Atom,
+    types :: Atom,
+    compat :: Atom,
+    vmods :: Ptr Atom,
+    indicators :: Ptr Atom, -- array
+    groups :: Ptr Atom, -- array
+    keys :: Ptr XkbKeyNameRec,
+    key_aliases :: Ptr CChar, -- dont care XkbKeyAliasRec,
+    radio_groups :: Ptr Atom,
+    phys_symbols :: Atom,
+    num_keys :: CUChar,
+    num_key_aliases :: CUChar,
+    num_rg :: CUShort
+}
+
+--
+-- the t_ before map, indicators and compat are just because of name collisions
+--
+data XkbDescRec = XkbDescRec {
+    t_dpy :: Ptr CChar, -- struct _XDisplay* ; don't care
+    flags :: CUShort,
+    device_spec :: CUShort,
+    min_key_code :: KeyCode,
+    max_key_code :: KeyCode,
+    ctrls :: Ptr CChar, -- XkbControlsPtr ;  dont' care
+    server :: Ptr CChar, -- XkbServerMapPtr ;  dont' care
+    t_map :: Ptr CChar, --XkbClientMapPtr ;  dont' care
+    t_indicators :: Ptr CChar, -- XkbIndicatorPtr ;  dont' care
+	names :: Ptr XkbNamesRec, -- array
+    t_compat :: Ptr CChar, -- XkbCompatMap ;  dont' care
+    geom :: Ptr CChar -- XkbGeometryPtr ;  dont' care
+
+}
+
+instance Storable XkbKeyNameRec where
+    sizeOf _ = (#size XkbKeyNameRec)
+    alignment _ = alignment (undefined :: CUShort)
+    peek ptr = do
+        r_name <- (#peek XkbKeyNameRec, name) ptr
+
+        return XkbKeyNameRec {
+            name = r_name
+        }
+
+instance Storable XkbKeyAliasRec where
+    sizeOf _ = (#size XkbKeyAliasRec)
+    alignment _ = alignment (undefined :: CUShort)
+    peek ptr = do
+        r_real <- (#peek XkbKeyAliasRec, real) ptr
+        r_alias <- (#peek XkbKeyAliasRec, alias) ptr
+
+        return XkbKeyAliasRec {
+            real = r_real,
+            t_alias = r_alias
+        }
+
+instance Storable XkbNamesRec where
+    sizeOf _ = (#size XkbNamesRec)
+    alignment _ = alignment (undefined :: CUShort)
+    peek ptr = do
+        r_keycodes <- (#peek XkbNamesRec, keycodes) ptr
+        r_geometry <- (#peek XkbNamesRec, geometry) ptr
+        r_symbols <- (#peek XkbNamesRec, symbols ) ptr
+        r_types <- (#peek XkbNamesRec, types ) ptr
+        r_compat <- (#peek XkbNamesRec, compat ) ptr  
+        r_vmods <- (#peek XkbNamesRec,  vmods ) ptr
+        r_indicators <- (#peek XkbNamesRec, indicators ) ptr  
+        r_groups <- (#peek XkbNamesRec, groups ) ptr 
+        r_keys <- (#peek XkbNamesRec, keys ) ptr   
+        r_key_aliases <- (#peek XkbNamesRec, key_aliases  ) ptr
+        r_radio_groups <- (#peek XkbNamesRec, radio_groups  ) ptr 
+        r_phys_symbols <- (#peek XkbNamesRec, phys_symbols ) ptr  
+        r_num_keys <- (#peek XkbNamesRec,num_keys  ) ptr
+        r_num_key_aliases <- (#peek XkbNamesRec, num_key_aliases  ) ptr
+        r_num_rg <- (#peek XkbNamesRec, num_rg ) ptr
+
+        return XkbNamesRec {
+            keycodes = r_keycodes,
+            t_geometry = r_geometry,
+            symbols = r_symbols,
+            types = r_types,
+            compat = r_compat,
+            vmods = r_vmods,
+            indicators = r_indicators,
+            groups = r_groups,
+            keys = r_keys,
+            key_aliases = r_key_aliases,
+            radio_groups = r_radio_groups,
+            phys_symbols = r_phys_symbols,
+            num_keys = r_num_keys,
+            num_key_aliases = r_num_key_aliases,
+            num_rg = r_num_rg
+       }
+
+instance Storable XkbDescRec where
+    sizeOf _ = (#size XkbDescRec)
+    alignment _ = alignment (undefined :: CUShort)
+    peek ptr = do
+        r_dpy <- (#peek XkbDescRec, dpy) ptr
+        r_flags <- (#peek XkbDescRec, flags) ptr
+        r_device_spec <- (#peek XkbDescRec, device_spec) ptr
+        r_min_key_code <- (#peek XkbDescRec, min_key_code) ptr
+        r_max_key_code <- (#peek XkbDescRec, max_key_code) ptr
+        r_ctrls <- (#peek XkbDescRec, ctrls) ptr
+        r_server <- (#peek XkbDescRec, server) ptr
+        r_map <- (#peek XkbDescRec, map) ptr
+        r_indicators <- (#peek XkbDescRec, indicators) ptr
+        r_names <- (#peek XkbDescRec, names) ptr
+        r_compat <- (#peek XkbDescRec, compat) ptr
+        r_geom <- (#peek XkbDescRec, geom) ptr
+
+        return XkbDescRec {
+            t_dpy = r_dpy,
+            flags = r_flags,
+            device_spec = r_device_spec,
+            min_key_code = r_min_key_code,
+            max_key_code = r_max_key_code,
+            ctrls = r_ctrls,
+            server = r_server,
+            t_map = r_map,
+            t_indicators = r_indicators,
+            names = r_names,
+            t_compat = r_compat,
+            geom = r_geom
+        }
+
+--
+-- C bindings
+--
+
+foreign import ccall unsafe "X11/XKBlib.h XkbAllocKeyboard"
+    xkbAllocKeyboard :: IO (Ptr XkbDescRec)
+
+foreign import ccall unsafe "X11/XKBlib.h XkbGetNames"
+    xkbGetNames :: Display -> CUInt -> (Ptr XkbDescRec)  -> IO Status
+
+foreign import ccall unsafe "X11/XKBlib.h XGetAtomName"
+    xGetAtomName :: Display -> Atom -> IO CString
+
+foreign import ccall unsafe "X11/XKBlib.h XkbFreeNames"
+    xkbFreeNames :: (Ptr XkbDescRec) -> CUInt -> CInt -> IO ()
+
+foreign import ccall unsafe "X11/XKBlib.h XkbFreeKeyboard"
+    xkbFreeKeyboard :: (Ptr XkbDescRec) -> CUInt -> CInt -> IO ()
+
+foreign import ccall unsafe "X11/XKBlib.h XkbSelectEventDetails"
+	xkbSelectEventDetails :: Display -> CUInt -> CUInt -> CULong -> CULong -> IO CUInt
+
+foreign import ccall unsafe "X11/XKBlib.h XkbSelectEvents"
+	xkbSelectEvents :: Display -> CUInt -> CUInt -> CUInt -> IO CUInt
+
+
+xkbUseCoreKbd :: CUInt
+xkbUseCoreKbd = #const XkbUseCoreKbd
+
+xkbStateNotify :: CUInt
+xkbStateNotify = #const XkbStateNotify
+
+xkbMapNotify :: CUInt
+xkbMapNotify = #const XkbMapNotify
+
+xkbMapNotifyMask :: CUInt
+xkbMapNotifyMask = #const XkbMapNotifyMask
+
+xkbNewKeyboardNotifyMask :: CUInt
+xkbNewKeyboardNotifyMask  = #const XkbNewKeyboardNotifyMask
+
+xkbAllStateComponentsMask :: CULong
+xkbAllStateComponentsMask = #const XkbAllStateComponentsMask
+
+xkbGroupStateMask :: CULong
+xkbGroupStateMask = #const XkbGroupStateMask
+
+xkbSymbolsNameMask :: CUInt
+xkbSymbolsNameMask = #const XkbSymbolsNameMask
+
+xkbGroupNamesMask :: CUInt
+xkbGroupNamesMask = #const XkbGroupNamesMask
+
+data KbdOpts = KbdOpts
+	{ errorString :: String
+	, src :: [String]
+    , rpl :: [String]
+	}
+
+defaultOpts :: KbdOpts
+defaultOpts = KbdOpts
+	{ errorString = "Err"
+	, src = []
+	, rpl = []
+	}
+
+options :: [OptDescr (KbdOpts -> KbdOpts)]
+options =
+	[ Option ['e'] ["error"] (ReqArg (\x o -> o { errorString = x }) "") ""
+	, Option ['s'] ["src"] (ReqArg (\x o -> o { src = [x] ++ src o }) "") ""
+	, Option ['r'] ["rpl"] (ReqArg (\x o -> o { rpl = [x] ++ rpl o }) "") ""
+	]
+
+parseOpts :: [String] -> IO KbdOpts
+parseOpts argv =
+	case getOpt Permute options argv of
+		(o, _, []) -> return $ foldr id defaultOpts o
+		(_, _, errs) -> ioError . userError $ concat errs
+
+
+-- gets the layout string
+getLayoutStr :: KbdOpts -> Display -> IO String
+getLayoutStr opts dpy =  do
+        kbdDescPtr <- xkbAllocKeyboard
+        status <- xkbGetNames dpy xkbSymbolsNameMask kbdDescPtr
+        str <- getLayoutStr' opts status dpy kbdDescPtr
+        xkbFreeNames kbdDescPtr xkbGroupNamesMask 1
+        xkbFreeKeyboard kbdDescPtr 0 1
+        return str
+
+getLayoutStr' :: KbdOpts -> Status -> Display -> (Ptr XkbDescRec) -> IO String
+getLayoutStr' opts st dpy kbdDescPtr =
+        if st == 0 then -- Success
+            do
+            kbdDesc <- peek kbdDescPtr
+            nameArray <- peek (names kbdDesc)
+            atom <- xGetAtomName dpy (symbols nameArray)
+            str <- peekCString atom
+            return str
+        else -- Behaviour on error
+            do
+            return (errorString opts)
+
+
+-- 'Bad' prefixes of layouts
+noLaySymbols :: [String]
+noLaySymbols = ["group", "inet", "ctr", "pc", "ctrl"]
+
+
+-- splits the layout string into the actual layouts
+splitLayout :: String -> [String]
+splitLayout s = splitLayout' noLaySymbols $ split s '+' 
+
+splitLayout' :: [String] ->  [String] -> [String]
+--                  end of recursion, remove empty strings
+splitLayout' [] s = map (takeWhile (\x -> x /= ':')) $ filter (\x -> length x > 0) s
+--                    remove current string if it has a 'bad' prefix
+splitLayout' bad s  = splitLayout' (tail bad) [x | x <- s, not $ isPrefixOf (head bad) x]
+
+-- split String at each Char
+split :: String -> Char -> [String]
+split [] _ = [""]
+split (c:cs) delim
+    | c == delim = "" : rest
+    | otherwise = (c : head rest) : tail rest
+        where
+            rest = split cs delim
+
+-- replaces input string if on search list (exact match) with corresponding
+-- element on replacement list.
+-- 
+-- if not found, return string unchanged
+searchReplaceLayout :: KbdOpts -> String -> String
+searchReplaceLayout opts s = let c = elemIndex s (src opts) in
+    case c of
+        Nothing -> s
+        x -> let i = (fromJust x) in
+            if i >= length (rpl opts) then
+                s
+            else
+                (rpl opts)!!i
+
+-- returns the active layout
+getKbdLay :: Display -> KbdOpts -> IO String
+getKbdLay dpy opts = do
+        lay <- getLayoutStr opts dpy
+        curLay <- getKbdLayout dpy
+        return $ searchReplaceLayout opts $ (splitLayout lay)!!(curLay)
+
+
+
+data Kbd = Kbd [String]
+	deriving (Read, Show)
+
+instance Exec Kbd where
+	alias (Kbd _) = "kbd"
+	start (Kbd s) cb = do
+
+        dpy <- openDisplay ""
+        -- parse parameters
+        opts <- parseOpts s
+
+        -- initial set of layout
+        cb =<< (getKbdLay dpy opts)
+
+        -- enable listing for
+        -- group changes
+        _ <- xkbSelectEventDetails dpy xkbUseCoreKbd xkbStateNotify xkbAllStateComponentsMask xkbGroupStateMask
+        -- layout/geometry changes
+        _ <- xkbSelectEvents dpy  xkbUseCoreKbd xkbNewKeyboardNotifyMask xkbNewKeyboardNotifyMask
+
+        allocaXEvent $ \e -> forever $ do
+            nextEvent' dpy e
+            _ <- getEvent e
+            cb =<< (getKbdLay dpy opts)
+
+        closeDisplay dpy
+        return ()
+
+-- vim:ft=haskell:ts=4:shiftwidth=4:softtabstop=4:expandtab:foldlevel=20:
+
diff --git a/xmobar.cabal b/xmobar.cabal
index 5d77997..72c1c00 100644
--- a/xmobar.cabal
+++ b/xmobar.cabal
@@ -68,10 +68,11 @@ executable xmobar
       Xmobar, Config, Parsers, Commands, XUtil, StatFS, Runnable,
       Plugins, Plugins.CommandReader, Plugins.Date, Plugins.EWMH,
       Plugins.PipeReader, Plugins.StdinReader, Plugins.XMonadLog,
-      Plugins.Utils, Plugins.Monitors, Plugins.Monitors.Batt,
-      Plugins.Monitors.Common, Plugins.Monitors.CoreCommon,
-      Plugins.Monitors.CoreTemp, Plugins.Monitors.CpuFreq,
-      Plugins.Monitors.Cpu, Plugins.Monitors.Disk, Plugins.Monitors.Mem,
+      Plugins.Utils, Plugins.Kbd, Plugins.Monitors,
+      Plugins.Monitors.Batt, Plugins.Monitors.Common,
+      Plugins.Monitors.CoreCommon, Plugins.Monitors.CoreTemp,
+      Plugins.Monitors.CpuFreq, Plugins.Monitors.Cpu,
+      Plugins.Monitors.Disk, Plugins.Monitors.Mem,
       Plugins.Monitors.MultiCpu, Plugins.Monitors.Net,
       Plugins.Monitors.Swap, Plugins.Monitors.Thermal,
       Plugins.Monitors.ThermalZone, Plugins.Monitors.Top,