clipboard-sync-same-display.diff

diff --git a/chroot-bin/croutonclip b/chroot-bin/croutonclip
index a280419..226f26d 100755
--- a/chroot-bin/croutonclip
+++ b/chroot-bin/croutonclip
@@ -5,6 +5,7 @@
 #
 # Synchronizes clipboard between X displays, making use of crouton's WebSocket
 # server and Chromium extension to synchronize the clipboard with Chromium OS
+# Define XMETHOD variable (x11, xephyr or cros) in prior to run this script.
 
 VERBOSE=''
 
@@ -47,7 +48,7 @@ copyclip() {
 
     # Copy clipboard content from the current display
     {
-        if [ "$current" = ':0' ]; then
+        if [ "$current" = 'aura' ]; then
             echo -n 'R' | websocketcommand
         else
             # Check if display is still running
@@ -68,7 +69,7 @@ copyclip() {
         fi
 
         # Paste clipboard content to the next display
-        if [ "$next" = ':0' ]; then
+        if [ "$next" = 'aura' ]; then
             STATUS="`(echo -n 'W'; cat) | websocketcommand`"
             if [ "$STATUS" != 'WOK' ]; then
                 # Write failed, skip Chromium OS (do not update $current)
@@ -125,20 +126,19 @@ waitwebsocket() {
 croutonwebsocket &
 addtrap "kill $! 2>/dev/null"
 
-xmethod="`readlink -f '/etc/X11/xinit/xserverrc'`"
-xmethod="${xmethod##*-}"
-
 # For both x11/xephyr, the code works as follow:
 #  - A command outputs one line per event (window/tty change).
 #  - In a second subshell, read these events, one by one, and transfer the
 #    clipboard content.
 # This makes sure we do not miss any events and that we copy the clipboard
 # around in the right sequence.
+# For cros, guest OS shares X display with Chrome OS (:0).
 
-if [ "$xmethod" = 'xephyr' ]; then
+case "$XMETHOD" in
+'xephyr' | 'cros')
     # Assume current display is Chromium OS, as the awk script does not detect
     # the current window
-    current=':0'
+    current='aura'
 
     # Wait for ratpoison to come up
     while ! host-x11 xprop -root _NET_WM_NAME | grep -q 'ratpoison'; do
@@ -175,7 +175,9 @@ if [ "$xmethod" = 'xephyr' ]; then
             # Translate window id to display number
             id="${line%,}"
             if [ "$id" = "$aura" ]; then
-                display=":0"
+                display="aura"
+            elif [ "$XMETHOD" = 'cros' ]; then
+                display=':0'
             else
                 # This relies on WM_NAME looking like "Xephyr on :1.0 (...)"
                 display="`host-x11 xprop -format WM_NAME 8s '\t$0' \
@@ -185,8 +187,8 @@ if [ "$xmethod" = 'xephyr' ]; then
 
             copyclip "$display"
         done
-    }
-elif [ "$xmethod" = 'x11' ]; then
+    };;
+'x11')
     # No need to set $current:
     # croutonvtmonitor outputs the current tty right after it is started
 
@@ -204,7 +206,7 @@ elif [ "$xmethod" = 'x11' ]; then
         while read tty; do
             display=''
             if [ "$tty" = "tty1" ]; then
-                display=":0"
+                display="aura"
             else
                 # Find which process owns the tty
                 process="`ps -o pid= -t "$tty" | sed 's/ //g'`"
@@ -222,9 +224,8 @@ elif [ "$xmethod" = 'x11' ]; then
 
             copyclip "$display"
         done
-    }
-else
-    echo "Invalid xmethod='$xmethod'." >&2
-fi
-
+    };;
+*)
+    echo "Invalid xmethod='$XMETHOD'." >&2;;
+esac
 exit 1

croutonclip

#!/bin/sh -e
# Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#
# Synchronizes clipboard between X displays, making use of crouton's WebSocket
# server and Chromium extension to synchronize the clipboard with Chromium OS
# Define XMETHOD variable (x11, xephyr or cros) in prior to run this script.

VERBOSE=''

. "`dirname "$0"`/../installer/functions"

PIPEDIR='/tmp/crouton-ext'
PIPEIN="$PIPEDIR/in"
PIPEOUT="$PIPEDIR/out"
PIPELOCK="$PIPEDIR/lock"

# Write a command to croutonwebsocket, and read back response
websocketcommand() {
    # Check that $PIPEDIR and the FIFO pipes exist
    if ! [ -d "$PIPEDIR" -a -p "$PIPEIN" -a -p "$PIPEOUT" ]; then
        echo "EError $PIPEIN or $PIPEOUT are not pipes."
        exit 0
    fi

    (
        flock 5
        cat > "$PIPEIN"
        cat "$PIPEOUT"
    ) 5>"$PIPELOCK"
}

current=''

copyclip() {
    next="$1"

    # Do not copy if next is empty (display cannot be detected), or
    # if current == next. Also set current=$next if $current is empty
    if [ -z "$next" -o "${current:="$next"}" = "$next" ]; then
        return 0
    fi

    if [ -n "$VERBOSE" ]; then
        echo ">>Current: $current>>"
    fi

    # Copy clipboard content from the current display
    {
        if [ "$current" = 'aura' ]; then
            echo -n 'R' | websocketcommand
        else
            # Check if display is still running
            if DISPLAY="$current" xdpyinfo >/dev/null 2>&1; then
                echo -n 'R'
                DISPLAY="$current" xclip -o -sel clip
            else
                echo -n "EUnable to open display '$current'."
            fi
        fi
    } | (
        STATUS="`head -c 1`"
        if [ "$STATUS" != 'R' ]; then
            echo -n "croutonwebsocket error: " >&2
            cat >&2
            # Stop here (the clipboard content is lost in this case)
            exit 0
        fi

        # Paste clipboard content to the next display
        if [ "$next" = 'aura' ]; then
            STATUS="`(echo -n 'W'; cat) | websocketcommand`"
            if [ "$STATUS" != 'WOK' ]; then
                # Write failed, skip Chromium OS (do not update $current)
                echo -n "croutonwebsocket error: $STATUS" >&2
                exit 1
            fi
        else
            # Do not override content if it "looks" the same
            # (we might have rich text or other content in the clipboard)
            cliptmp="`mktemp "croutonclip.XXX" --tmpdir=/tmp`"
            trap "rm -f '$cliptmp'" 0
            cat > $cliptmp

            if ! DISPLAY="$next" xclip -o -sel clip | diff -q - "$cliptmp" > /dev/null; then
                cat "$cliptmp" | DISPLAY="$next" xclip -i -sel clip
            fi
        fi
    ) && current="$next"

    if [ -n "$VERBOSE" ]; then
        echo "<<Next: $current<<"
    fi
}

# Wait for the websocket server to get connected to the extension
# Timeout after 10 seconds (twice crouton extension retry period)
waitwebsocket() {
    timeout=10
    while [ $timeout -gt 0 ]; do
        if [ -n "$VERBOSE" ]; then
            echo "Ping..."
        fi

        # Prepare and send a ping message
        MSG="PING$$$timeout"
        STATUS="`echo -n "$MSG" | websocketcommand`"
        if [ "$STATUS" = "$MSG" ]; then
            if [ -n "$VERBOSE" ]; then
                echo "OK!"
            fi
            return 0
        fi

        if [ -n "$VERBOSE" ]; then
            echo "$STATUS"
        fi

        sleep 1
        timeout=$(($timeout-1))
    done
    echo "Timeout waiting for extension to connect." >&2
}

croutonwebsocket &
addtrap "kill $! 2>/dev/null"

# For both x11/xephyr, the code works as follow:
#  - A command outputs one line per event (window/tty change).
#  - In a second subshell, read these events, one by one, and transfer the
#    clipboard content.
# This makes sure we do not miss any events and that we copy the clipboard
# around in the right sequence.
# For cros, guest OS shares X display with Chrome OS (:0).

case "$XMETHOD" in
'xephyr' | 'cros')
    # Assume current display is Chromium OS, as the awk script does not detect
    # the current window
    current='aura'

    # Wait for ratpoison to come up
    while ! host-x11 xprop -root _NET_WM_NAME | grep -q 'ratpoison'; do
        sleep .1
    done 2>&-

    # Get the aura root window number (hex)
    aura="`host-x11 xwininfo -root -children | mawk '/aura_root/ {print $1}'`"

    # Detect window change using MapNotify events that do not have the
    # override-redirect flag ("override NO" in xev events)
    {
        host-x11 xev -root &
        cpid=$!
        addtrap "kill $cpid 2>/dev/null"
        if ! wait $cpid; then
            echo "croutonclip: xev error ($?)"
        fi
    } | mawk -W interactive '
        m {
            if ($6 == "NO") {
                print $4 # Window id
            }
            m = 0
        }
        /^MapNotify/ {
            m = 1
        }
    ' | {
        # Wait for extension to connect (do not fail even if it times out)
        waitwebsocket

        while read line; do
            # Translate window id to display number
            id="${line%,}"
            if [ "$id" = "$aura" ]; then
                display="aura"
            elif [ "$XMETHOD" = 'cros' ]; then
                display=':0'
            else
                # This relies on WM_NAME looking like "Xephyr on :1.0 (...)"
                display="`host-x11 xprop -format WM_NAME 8s '\t$0' \
                        -id "$id" WM_NAME | cut -f 2 | \
                        sed -n -e 's/^\"Xephyr on \(:[0-9]\{1,\}\).*$/\1/p'`"
            fi

            copyclip "$display"
        done
    };;
'x11')
    # No need to set $current:
    # croutonvtmonitor outputs the current tty right after it is started

    {
        croutonvtmonitor &
        cpid=$!
        addtrap "kill $cpid 2>/dev/null"
        if ! wait $cpid; then
            echo "croutonclip: croutonvtmonitor error ($?)"
        fi
    } | {
        # Wait for extension to connect (do not fail even if it times out)
        waitwebsocket

        while read tty; do
            display=''
            if [ "$tty" = "tty1" ]; then
                display="aura"
            else
                # Find which process owns the tty
                process="`ps -o pid= -t "$tty" | sed 's/ //g'`"

                if [ -n "$process" ]; then
                    # Find which display the process owns (if any)
                    for lock in /tmp/.X*-lock; do
                        if grep -q "^ *$process$" "$lock"; then
                            display="${lock#/tmp/.X}"
                            display=":${display%-lock}"
                        fi
                    done
                fi
            fi

            copyclip "$display"
        done
    };;
*)
    echo "Invalid xmethod='$XMETHOD'." >&2;;
esac
exit 1

One more thing... Trying to figure out how to integrate this neatly in the crouton framework.

You could remove lines 130-131, and instead rely on an environment variable XMETHOD that needs to be passed to the script. That removes the need for the xserverr-cros hack, and make it possible to use the script in both cros or x11/xephyr context.

You genius, all hacks are removed now. Thanks again!