[repo, undo] Finish repository-side implementation of the undo feature (closes #893940)
1) Changes API for undo_transaction in order to raise an exception:
the previous API returned a sequence of error, the user of the API
needed to be careful to check explicitly. We change this for it to
raise an UndoException with the list of errors as an attribute.
2) The server-side support for undoing update actions is finished
3) The configuration for `undo-support` is now a simple boolean
Beware of the costs, both in DB space and in number of requests
on the RDBMS backend, once this feture is activated.
4) Adds a txuuid param/attribute to the existing NoSuchTransaction
exception.
#!/bin/sh
# $Id: xvfb-run 2027 2004-11-16 14:54:16Z branden $
# This script starts an instance of Xvfb, the "fake" X server, runs a command
# with that server available, and kills the X server when done. The return
# value of the command becomes the return value of this script.
#
# If anyone is using this to build a Debian package, make sure the package
# Build-Depends on xvfb, xbase-clients, and xfonts-base.
set -e
PROGNAME=xvfb-run
SERVERNUM=99
AUTHFILE=
ERRORFILE=/dev/null
STARTWAIT=3
XVFBARGS="-screen 0 640x480x8"
LISTENTCP="-nolisten tcp"
XAUTHPROTO=.
# Query the terminal to establish a default number of columns to use for
# displaying messages to the user. This is used only as a fallback in the event
# the COLUMNS variable is not set. ($COLUMNS can react to SIGWINCH while the
# script is running, and this cannot, only being calculated once.)
DEFCOLUMNS=$(stty size 2>/dev/null | awk '{print $2}') || true
if ! expr "$DEFCOLUMNS" : "[[:digit:]]\+$" >/dev/null 2>&1; then
DEFCOLUMNS=80
fi
# Display a message, wrapping lines at the terminal width.
message () {
echo "$PROGNAME: $*" | fmt -t -w ${COLUMNS:-$DEFCOLUMNS}
}
# Display an error message.
error () {
message "error: $*" >&2
}
# Display a usage message.
usage () {
if [ -n "$*" ]; then
message "usage error: $*"
fi
cat <<EOF
Usage: $PROGNAME [OPTION ...] COMMAND
Run COMMAND (usually an X client) in a virtual X server environment.
Options:
-a --auto-servernum try to get a free server number, starting at
--server-num
-e FILE --error-file=FILE file used to store xauth errors and Xvfb
output (default: $ERRORFILE)
-f FILE --auth-file=FILE file used to store auth cookie
(default: ./.Xauthority)
-h --help display this usage message and exit
-n NUM --server-num=NUM server number to use (default: $SERVERNUM)
-l --listen-tcp enable TCP port listening in the X server
-p PROTO --xauth-protocol=PROTO X authority protocol name to use
(default: xauth command's default)
-s ARGS --server-args=ARGS arguments (other than server number and
"-nolisten tcp") to pass to the Xvfb server
(default: "$XVFBARGS")
-w DELAY --wait=DELAY delay in seconds to wait for Xvfb to start
before running COMMAND (default: $STARTWAIT)
EOF
}
# Find a free server number by looking at .X*-lock files in /tmp.
find_free_servernum() {
# Sadly, the "local" keyword is not POSIX. Leave the next line commented in
# the hope Debian Policy eventually changes to allow it in /bin/sh scripts
# anyway.
#local i
i=$SERVERNUM
while [ -f /tmp/.X$i-lock ]; do
i=$(($i + 1))
done
echo $i
}
# Clean up files
clean_up() {
if [ -e "$AUTHFILE" ]; then
XAUTHORITY=$AUTHFILE xauth remove ":$SERVERNUM" >>"$ERRORFILE" 2>&1
fi
if [ -n "$XVFB_RUN_TMPDIR" ]; then
if ! rm -r "$XVFB_RUN_TMPDIR"; then
error "problem while cleaning up temporary directory"
exit 5
fi
fi
if [ -n "$XVFBPID" ]; then
kill $XVFBPID
fi
}
# Parse the command line.
ARGS=$(getopt --options +ae:f:hn:lp:s:w: \
--long auto-servernum,error-file:,auth-file:,help,server-num:,listen-tcp,xauth-protocol:,server-args:,wait: \
--name "$PROGNAME" -- "$@")
GETOPT_STATUS=$?
if [ $GETOPT_STATUS -ne 0 ]; then
error "internal error; getopt exited with status $GETOPT_STATUS"
exit 6
fi
eval set -- "$ARGS"
while :; do
case "$1" in
-a|--auto-servernum) SERVERNUM=$(find_free_servernum); AUTONUM="yes" ;;
-e|--error-file) ERRORFILE="$2"; shift ;;
-f|--auth-file) AUTHFILE="$2"; shift ;;
-h|--help) SHOWHELP="yes" ;;
-n|--server-num) SERVERNUM="$2"; shift ;;
-l|--listen-tcp) LISTENTCP="" ;;
-p|--xauth-protocol) XAUTHPROTO="$2"; shift ;;
-s|--server-args) XVFBARGS="$2"; shift ;;
-w|--wait) STARTWAIT="$2"; shift ;;
--) shift; break ;;
*) error "internal error; getopt permitted \"$1\" unexpectedly"
exit 6
;;
esac
shift
done
if [ "$SHOWHELP" ]; then
usage
exit 0
fi
if [ -z "$*" ]; then
usage "need a command to run" >&2
exit 2
fi
if ! which xauth >/dev/null; then
error "xauth command not found"
exit 3
fi
# tidy up after ourselves
trap clean_up EXIT
# If the user did not specify an X authorization file to use, set up a temporary
# directory to house one.
if [ -z "$AUTHFILE" ]; then
XVFB_RUN_TMPDIR="$(mktemp -d -t $PROGNAME.XXXXXX)"
# Create empty file to avoid xauth warning
AUTHFILE=$(tempfile -n "$XVFB_RUN_TMPDIR/Xauthority")
fi
# Start Xvfb.
MCOOKIE=$(mcookie)
tries=10
while [ $tries -gt 0 ]; do
tries=$(( $tries - 1 ))
XAUTHORITY=$AUTHFILE xauth source - << EOF >>"$ERRORFILE" 2>&1
add :$SERVERNUM $XAUTHPROTO $MCOOKIE
EOF
XAUTHORITY=$AUTHFILE Xvfb ":$SERVERNUM" $XVFBARGS $LISTENTCP >>"$ERRORFILE" 2>&1 &
XVFBPID=$!
sleep "$STARTWAIT"
if kill -0 $XVFBPID 2>/dev/null; then
break
elif [ -n "$AUTONUM" ]; then
# The display is in use so try another one (if '-a' was specified).
SERVERNUM=$((SERVERNUM + 1))
SERVERNUM=$(find_free_servernum)
continue
fi
error "Xvfb failed to start" >&2
exit 1
done
# Start the command and save its exit status.
set +e
DISPLAY=:$SERVERNUM XAUTHORITY=$AUTHFILE "$@" 2>&1
RETVAL=$?
set -e
# Return the executed command's exit status.
exit $RETVAL
# vim:set ai et sts=4 sw=4 tw=80: