Bindings to ioctl for setting/getting window size.

Foreign.chs

{-# LANGUAGE ForeignFunctionInterface #-}
{-# LANGUAGE EmptyDataDecls #-}

#include <sys/ttycom.h>
#include <sys/ioctl.h>

#c
typedef struct winsize winsize;
#endc

module Tabula.TTY.Foreign where
  import Control.Applicative
  import Control.Monad (liftM)

  import Foreign.Storable
  import Foreign.Ptr
  import Foreign.C

  import System.Posix.IOCtl

  {#enum define TIO {TIOCGWINSZ as GetWinsz, TIOCSWINSZ as SetWinsz} deriving (Eq) #}

  data WindowSize = WindowSize {
      ws_row :: Int
    , ws_col :: Int
    , ws_xpixel :: Int
    , ws_ypixel :: Int
  }

  instance Storable WindowSize where
    sizeOf _ = {#sizeof winsize#}
    alignment _ = {#alignof winsize#}
    peek p = WindowSize
      <$> liftM fromIntegral ({#get winsize->ws_row #} p)
      <*> liftM fromIntegral ({#get winsize->ws_col #} p)
      <*> liftM fromIntegral ({#get winsize->ws_xpixel #} p)
      <*> liftM fromIntegral ({#get winsize->ws_ypixel #} p)
    poke p x = do
      {#set winsize.ws_row #} p (fromIntegral $ ws_row)
      {#set winsize.ws_col #} p (fromIntegral $ ws_col)
      {#set winsize.ws_xpixel #} p (fromIntegral $ ws_xpixel)
      {#set winsize.ws_ypixel #} p (fromIntegral $ ws_ypixel)

  data TIOCGWINSZ

  instance IOControl TIOCGWINSZ WindowSize where
    ioctlReq = GetWinsz

  data TIOCSWINSZ

  instance IOControl TIOCSWINSZ WindowSize where
    ioctlReq = SetWinsz

The {#enum define} in this doesn't work, unfortunately. I moved to using hsc2hs instead.