#!/bin/bash
 #

 # functions-common - Common functions used by DevStack components
 #
 # The canonical copy of this file is maintained in the DevStack repo.
 # All modifications should be made there and then sync'ed to other repos
 # as required.
 #
 # This file is sorted alphabetically within the function groups.
 #
 # - Config Functions
 # - Control Functions
 # - Distro Functions
 # - Git Functions
 # - OpenStack Functions
 # - Package Functions
 # - Process Functions
 # - Python Functions
 # - Service Functions

 # - System Functions

 #
 # The following variables are assumed to be defined by certain functions:
 #
 # - ``ENABLED_SERVICES``
 # - ``ERROR_ON_CLONE``
 # - ``FILES``
 # - ``OFFLINE``
 # - ``RECLONE``

 # - ``REQUIREMENTS_DIR``
 # - ``STACK_USER``

 # - ``TRACK_DEPENDS``

 # - ``UNDO_REQUIREMENTS``

 # - ``http_proxy``, ``https_proxy``, ``no_proxy``

 #

 
 # Save trace setting
 XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 

 # Global Config Variables
 declare -A GITREPO
 declare -A GITBRANCH
 declare -A GITDIR
 

 TRACK_DEPENDS=${TRACK_DEPENDS:-False}
 

 # Config Functions
 # ================
 
 # Append a new option in an ini file without replacing the old value
 # iniadd config-file section option value1 value2 value3 ...

 function iniadd {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     shift 3

     local values="$(iniget_multiline $file $section $option) $@"
     iniset_multiline $file $section $option $values

     $xtrace

 }
 
 # Comment an option in an INI file
 # inicomment config-file section option

 function inicomment {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3

     sed -i -e "/^\[$section\]/,/^\[.*\]/ s|^\($option[ \t]*=.*$\)|#\1|" "$file"

     $xtrace

 }
 
 # Get an option from an INI file
 # iniget config-file section option

 function iniget {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     local line

     line=$(sed -ne "/^\[$section\]/,/^\[.*\]/ { /^$option[ \t]*=/ p; }" "$file")
     echo ${line#*=}

     $xtrace

 }
 
 # Get a multiple line option from an INI file
 # iniget_multiline config-file section option

 function iniget_multiline {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     local values

     values=$(sed -ne "/^\[$section\]/,/^\[.*\]/ { s/^$option[ \t]*=[ \t]*//gp; }" "$file")
     echo ${values}

     $xtrace

 }
 
 # Determinate is the given option present in the INI file
 # ini_has_option config-file section option

 function ini_has_option {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     local line

     line=$(sed -ne "/^\[$section\]/,/^\[.*\]/ { /^$option[ \t]*=/ p; }" "$file")

     $xtrace

     [ -n "$line" ]
 }
 

 # Add another config line for a multi-line option.
 # It's normally called after iniset of the same option and assumes
 # that the section already exists.
 #
 # Note that iniset_multiline requires all the 'lines' to be supplied
 # in the argument list. Doing that will cause incorrect configuration
 # if spaces are used in the config values.
 #
 # iniadd_literal config-file section option value
 function iniadd_literal {
     local xtrace=$(set +o | grep xtrace)
     set +o xtrace
     local file=$1
     local section=$2
     local option=$3
     local value=$4
 
     [[ -z $section || -z $option ]] && return
 
     # Add it
     sed -i -e "/^\[$section\]/ a\\
 $option = $value
 " "$file"
 
     $xtrace
 }
 

 function inidelete {
     local xtrace=$(set +o | grep xtrace)
     set +o xtrace
     local file=$1
     local section=$2
     local option=$3
 
     [[ -z $section || -z $option ]] && return
 
     # Remove old values
     sed -i -e "/^\[$section\]/,/^\[.*\]/ { /^$option[ \t]*=/ d; }" "$file"
 
     $xtrace
 }
 

 # Set an option in an INI file
 # iniset config-file section option value

 function iniset {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     local value=$4
 
     [[ -z $section || -z $option ]] && return
 
     if ! grep -q "^\[$section\]" "$file" 2>/dev/null; then
         # Add section at the end
         echo -e "\n[$section]" >>"$file"
     fi
     if ! ini_has_option "$file" "$section" "$option"; then
         # Add it
         sed -i -e "/^\[$section\]/ a\\
 $option = $value
 " "$file"
     else
         local sep=$(echo -ne "\x01")
         # Replace it
         sed -i -e '/^\['${section}'\]/,/^\[.*\]/ s'${sep}'^\('${option}'[ \t]*=[ \t]*\).*$'${sep}'\1'"${value}"${sep} "$file"
     fi

     $xtrace

 }
 
 # Set a multiple line option in an INI file
 # iniset_multiline config-file section option value1 value2 valu3 ...

 function iniset_multiline {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3

     shift 3
     local values
     for v in $@; do
         # The later sed command inserts each new value in the line next to
         # the section identifier, which causes the values to be inserted in
         # the reverse order. Do a reverse here to keep the original order.
         values="$v ${values}"
     done
     if ! grep -q "^\[$section\]" "$file"; then
         # Add section at the end
         echo -e "\n[$section]" >>"$file"
     else
         # Remove old values
         sed -i -e "/^\[$section\]/,/^\[.*\]/ { /^$option[ \t]*=/ d; }" "$file"
     fi
     # Add new ones
     for v in $values; do
         sed -i -e "/^\[$section\]/ a\\
 $option = $v
 " "$file"
     done

     $xtrace

 }
 
 # Uncomment an option in an INI file
 # iniuncomment config-file section option

 function iniuncomment {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local file=$1
     local section=$2
     local option=$3
     sed -i -e "/^\[$section\]/,/^\[.*\]/ s|[^ \t]*#[ \t]*\($option[ \t]*=.*$\)|\1|" "$file"

     $xtrace

 }
 
 # Normalize config values to True or False
 # Accepts as False: 0 no No NO false False FALSE
 # Accepts as True: 1 yes Yes YES true True TRUE
 # VAR=$(trueorfalse default-value test-value)

 function trueorfalse {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local default=$1

     local literal=$2

     local testval=${!literal:-}

 
     [[ -z "$testval" ]] && { echo "$default"; return; }
     [[ "0 no No NO false False FALSE" =~ "$testval" ]] && { echo "False"; return; }
     [[ "1 yes Yes YES true True TRUE" =~ "$testval" ]] && { echo "True"; return; }
     echo "$default"

     $xtrace

 }
 

 function isset {
     nounset=$(set +o | grep nounset)
     set +o nounset
     [[ -n "${!1+x}" ]]
     result=$?
     $nounset
     return $result
 }

 
 # Control Functions
 # =================
 
 # Prints backtrace info
 # filename:lineno:function
 # backtrace level
 function backtrace {
     local level=$1
     local deep=$((${#BASH_SOURCE[@]} - 1))
     echo "[Call Trace]"
     while [ $level -le $deep ]; do
         echo "${BASH_SOURCE[$deep]}:${BASH_LINENO[$deep-1]}:${FUNCNAME[$deep-1]}"
         deep=$((deep - 1))
     done
 }
 
 # Prints line number and "message" then exits
 # die $LINENO "message"

 function die {

     local exitcode=$?
     set +o xtrace
     local line=$1; shift
     if [ $exitcode == 0 ]; then
         exitcode=1
     fi
     backtrace 2
     err $line "$*"

     # Give buffers a second to flush
     sleep 1

     exit $exitcode
 }
 
 # Checks an environment variable is not set or has length 0 OR if the
 # exit code is non-zero and prints "message" and exits
 # NOTE: env-var is the variable name without a '$'
 # die_if_not_set $LINENO env-var "message"

 function die_if_not_set {

     local exitcode=$?

     local xtrace=$(set +o | grep xtrace)

     set +o xtrace
     local line=$1; shift
     local evar=$1; shift
     if ! is_set $evar || [ $exitcode != 0 ]; then
         die $line "$*"
     fi

     $xtrace

 }
 
 # Prints line number and "message" in error format
 # err $LINENO "message"

 function err {

     local exitcode=$?

     local xtrace=$(set +o | grep xtrace)

     set +o xtrace
     local msg="[ERROR] ${BASH_SOURCE[2]}:$1 $2"
     echo $msg 1>&2;

     if [[ -n ${LOGDIR} ]]; then
         echo $msg >> "${LOGDIR}/error.log"

     fi

     $xtrace

     return $exitcode
 }
 
 # Checks an environment variable is not set or has length 0 OR if the
 # exit code is non-zero and prints "message"
 # NOTE: env-var is the variable name without a '$'
 # err_if_not_set $LINENO env-var "message"

 function err_if_not_set {

     local exitcode=$?

     local xtrace=$(set +o | grep xtrace)

     set +o xtrace
     local line=$1; shift
     local evar=$1; shift
     if ! is_set $evar || [ $exitcode != 0 ]; then
         err $line "$*"
     fi

     $xtrace

     return $exitcode
 }
 
 # Exit after outputting a message about the distribution not being supported.
 # exit_distro_not_supported [optional-string-telling-what-is-missing]
 function exit_distro_not_supported {
     if [[ -z "$DISTRO" ]]; then
         GetDistro
     fi
 
     if [ $# -gt 0 ]; then
         die $LINENO "Support for $DISTRO is incomplete: no support for $@"
     else
         die $LINENO "Support for $DISTRO is incomplete."
     fi
 }
 
 # Test if the named environment variable is set and not zero length
 # is_set env-var

 function is_set {

     local var=\$"$1"
     eval "[ -n \"$var\" ]" # For ex.: sh -c "[ -n \"$var\" ]" would be better, but several exercises depends on this
 }
 
 # Prints line number and "message" in warning format
 # warn $LINENO "message"

 function warn {

     local exitcode=$?

     local xtrace=$(set +o | grep xtrace)

     set +o xtrace
     local msg="[WARNING] ${BASH_SOURCE[2]}:$1 $2"
     echo $msg 1>&2;

     if [[ -n ${LOGDIR} ]]; then
         echo $msg >> "${LOGDIR}/error.log"

     fi

     $xtrace

     return $exitcode
 }
 
 
 # Distro Functions
 # ================
 
 # Determine OS Vendor, Release and Update
 # Tested with OS/X, Ubuntu, RedHat, CentOS, Fedora
 # Returns results in global variables:

 # ``os_VENDOR`` - vendor name: ``Ubuntu``, ``Fedora``, etc
 # ``os_RELEASE`` - major release: ``14.04`` (Ubuntu), ``20`` (Fedora)
 # ``os_UPDATE`` - update: ex. the ``5`` in ``RHEL6.5``
 # ``os_PACKAGE`` - package type: ``deb`` or ``rpm``
 # ``os_CODENAME`` - vendor's codename for release: ``snow leopard``, ``trusty``

 os_VENDOR=""
 os_RELEASE=""
 os_UPDATE=""
 os_PACKAGE=""
 os_CODENAME=""

 # GetOSVersion

 function GetOSVersion {

     # Figure out which vendor we are
     if [[ -x "`which sw_vers 2>/dev/null`" ]]; then
         # OS/X
         os_VENDOR=`sw_vers -productName`
         os_RELEASE=`sw_vers -productVersion`
         os_UPDATE=${os_RELEASE##*.}
         os_RELEASE=${os_RELEASE%.*}
         os_PACKAGE=""
         if [[ "$os_RELEASE" =~ "10.7" ]]; then
             os_CODENAME="lion"
         elif [[ "$os_RELEASE" =~ "10.6" ]]; then
             os_CODENAME="snow leopard"
         elif [[ "$os_RELEASE" =~ "10.5" ]]; then
             os_CODENAME="leopard"
         elif [[ "$os_RELEASE" =~ "10.4" ]]; then
             os_CODENAME="tiger"
         elif [[ "$os_RELEASE" =~ "10.3" ]]; then
             os_CODENAME="panther"
         else
             os_CODENAME=""
         fi
     elif [[ -x $(which lsb_release 2>/dev/null) ]]; then
         os_VENDOR=$(lsb_release -i -s)
         os_RELEASE=$(lsb_release -r -s)
         os_UPDATE=""
         os_PACKAGE="rpm"
         if [[ "Debian,Ubuntu,LinuxMint" =~ $os_VENDOR ]]; then
             os_PACKAGE="deb"
         elif [[ "SUSE LINUX" =~ $os_VENDOR ]]; then
             lsb_release -d -s | grep -q openSUSE
             if [[ $? -eq 0 ]]; then
                 os_VENDOR="openSUSE"
             fi
         elif [[ $os_VENDOR == "openSUSE project" ]]; then
             os_VENDOR="openSUSE"
         elif [[ $os_VENDOR =~ Red.*Hat ]]; then
             os_VENDOR="Red Hat"
         fi
         os_CODENAME=$(lsb_release -c -s)
     elif [[ -r /etc/redhat-release ]]; then
         # Red Hat Enterprise Linux Server release 5.5 (Tikanga)
         # Red Hat Enterprise Linux Server release 7.0 Beta (Maipo)
         # CentOS release 5.5 (Final)
         # CentOS Linux release 6.0 (Final)
         # Fedora release 16 (Verne)
         # XenServer release 6.2.0-70446c (xenenterprise)
         os_CODENAME=""
         for r in "Red Hat" CentOS Fedora XenServer; do
             os_VENDOR=$r
             if [[ -n "`grep \"$r\" /etc/redhat-release`" ]]; then
                 ver=`sed -e 's/^.* \([0-9].*\) (\(.*\)).*$/\1\|\2/' /etc/redhat-release`
                 os_CODENAME=${ver#*|}
                 os_RELEASE=${ver%|*}
                 os_UPDATE=${os_RELEASE##*.}
                 os_RELEASE=${os_RELEASE%.*}
                 break
             fi
             os_VENDOR=""
         done
         os_PACKAGE="rpm"
     elif [[ -r /etc/SuSE-release ]]; then
         for r in openSUSE "SUSE Linux"; do
             if [[ "$r" = "SUSE Linux" ]]; then
                 os_VENDOR="SUSE LINUX"
             else
                 os_VENDOR=$r
             fi
 
             if [[ -n "`grep \"$r\" /etc/SuSE-release`" ]]; then
                 os_CODENAME=`grep "CODENAME = " /etc/SuSE-release | sed 's:.* = ::g'`
                 os_RELEASE=`grep "VERSION = " /etc/SuSE-release | sed 's:.* = ::g'`
                 os_UPDATE=`grep "PATCHLEVEL = " /etc/SuSE-release | sed 's:.* = ::g'`
                 break
             fi
             os_VENDOR=""
         done
         os_PACKAGE="rpm"
     # If lsb_release is not installed, we should be able to detect Debian OS
     elif [[ -f /etc/debian_version ]] && [[ $(cat /proc/version) =~ "Debian" ]]; then
         os_VENDOR="Debian"
         os_PACKAGE="deb"
         os_CODENAME=$(awk '/VERSION=/' /etc/os-release | sed 's/VERSION=//' | sed -r 's/\"|\(|\)//g' | awk '{print $2}')
         os_RELEASE=$(awk '/VERSION_ID=/' /etc/os-release | sed 's/VERSION_ID=//' | sed 's/\"//g')
     fi
     export os_VENDOR os_RELEASE os_UPDATE os_PACKAGE os_CODENAME
 }
 
 # Translate the OS version values into common nomenclature
 # Sets global ``DISTRO`` from the ``os_*`` values

 declare DISTRO
 

 function GetDistro {

     GetOSVersion
     if [[ "$os_VENDOR" =~ (Ubuntu) || "$os_VENDOR" =~ (Debian) ]]; then
         # 'Everyone' refers to Ubuntu / Debian releases by the code name adjective
         DISTRO=$os_CODENAME
     elif [[ "$os_VENDOR" =~ (Fedora) ]]; then
         # For Fedora, just use 'f' and the release
         DISTRO="f$os_RELEASE"
     elif [[ "$os_VENDOR" =~ (openSUSE) ]]; then
         DISTRO="opensuse-$os_RELEASE"
     elif [[ "$os_VENDOR" =~ (SUSE LINUX) ]]; then
         # For SLE, also use the service pack
         if [[ -z "$os_UPDATE" ]]; then
             DISTRO="sle${os_RELEASE}"
         else
             DISTRO="sle${os_RELEASE}sp${os_UPDATE}"
         fi

     elif [[ "$os_VENDOR" =~ (Red Hat) || \
         "$os_VENDOR" =~ (CentOS) || \
         "$os_VENDOR" =~ (OracleServer) ]]; then

         # Drop the . release as we assume it's compatible
         DISTRO="rhel${os_RELEASE::1}"
     elif [[ "$os_VENDOR" =~ (XenServer) ]]; then
         DISTRO="xs$os_RELEASE"
     else
         # Catch-all for now is Vendor + Release + Update
         DISTRO="$os_VENDOR-$os_RELEASE.$os_UPDATE"
     fi
     export DISTRO
 }
 
 # Utility function for checking machine architecture
 # is_arch arch-type
 function is_arch {

     [[ "$(uname -m)" == "$1" ]]

 }
 

 # Quick check for a rackspace host; n.b. rackspace provided images
 # have these Xen tools installed but a custom image may not.
 function is_rackspace {
     [ -f /usr/bin/xenstore-ls ] && \
         sudo /usr/bin/xenstore-ls vm-data | grep -q "Rackspace"
 }
 

 # Determine if current distribution is a Fedora-based distribution
 # (Fedora, RHEL, CentOS, etc).
 # is_fedora
 function is_fedora {
     if [[ -z "$os_VENDOR" ]]; then
         GetOSVersion
     fi
 

     [ "$os_VENDOR" = "Fedora" ] || [ "$os_VENDOR" = "Red Hat" ] || \
         [ "$os_VENDOR" = "CentOS" ] || [ "$os_VENDOR" = "OracleServer" ]

 }
 
 
 # Determine if current distribution is a SUSE-based distribution
 # (openSUSE, SLE).
 # is_suse
 function is_suse {
     if [[ -z "$os_VENDOR" ]]; then
         GetOSVersion
     fi
 
     [ "$os_VENDOR" = "openSUSE" ] || [ "$os_VENDOR" = "SUSE LINUX" ]
 }
 
 
 # Determine if current distribution is an Ubuntu-based distribution
 # It will also detect non-Ubuntu but Debian-based distros
 # is_ubuntu
 function is_ubuntu {
     if [[ -z "$os_PACKAGE" ]]; then
         GetOSVersion
     fi
     [ "$os_PACKAGE" = "deb" ]
 }
 
 
 # Git Functions
 # =============
 

 # Returns openstack release name for a given branch name
 # ``get_release_name_from_branch branch-name``

 function get_release_name_from_branch {

     local branch=$1

     if [[ $branch =~ "stable/" || $branch =~ "proposed/" ]]; then

         echo ${branch#*/}
     else
         echo "master"
     fi
 }
 

 # git clone only if directory doesn't exist already.  Since ``DEST`` might not
 # be owned by the installation user, we create the directory and change the
 # ownership to the proper user.

 # Set global ``RECLONE=yes`` to simulate a clone when dest-dir exists
 # Set global ``ERROR_ON_CLONE=True`` to abort execution with an error if the git repo

 # does not exist (default is False, meaning the repo will be cloned).

 # Uses globals ``ERROR_ON_CLONE``, ``OFFLINE``, ``RECLONE``

 # git_clone remote dest-dir branch
 function git_clone {

     local git_remote=$1
     local git_dest=$2
     local git_ref=$3
     local orig_dir=$(pwd)

     local git_clone_flags=""

     RECLONE=$(trueorfalse False RECLONE)

     if [[ "${GIT_DEPTH}" -gt 0 ]]; then

         git_clone_flags="$git_clone_flags --depth $GIT_DEPTH"
     fi
 

     if [[ "$OFFLINE" = "True" ]]; then
         echo "Running in offline mode, clones already exist"
         # print out the results so we know what change was used in the logs

         cd $git_dest

         git show --oneline | head -1

         cd $orig_dir

         return
     fi
 

     if echo $git_ref | egrep -q "^refs"; then

         # If our branch name is a gerrit style refs/changes/...

         if [[ ! -d $git_dest ]]; then

             [[ "$ERROR_ON_CLONE" = "True" ]] && \
                 die $LINENO "Cloning not allowed in this configuration"

             git_timed clone $git_clone_flags $git_remote $git_dest

         fi

         cd $git_dest
         git_timed fetch $git_remote $git_ref && git checkout FETCH_HEAD

     else
         # do a full clone only if the directory doesn't exist

         if [[ ! -d $git_dest ]]; then

             [[ "$ERROR_ON_CLONE" = "True" ]] && \
                 die $LINENO "Cloning not allowed in this configuration"

             git_timed clone $git_clone_flags $git_remote $git_dest

             cd $git_dest

             # This checkout syntax works for both branches and tags

             git checkout $git_ref

         elif [[ "$RECLONE" = "True" ]]; then
             # if it does exist then simulate what clone does if asked to RECLONE

             cd $git_dest

             # set the url to pull from and fetch

             git remote set-url origin $git_remote

             git_timed fetch origin

             # remove the existing ignored files (like pyc) as they cause breakage
             # (due to the py files having older timestamps than our pyc, so python
             # thinks the pyc files are correct using them)

             find $git_dest -name '*.pyc' -delete
 
             # handle git_ref accordingly to type (tag, branch)
             if [[ -n "`git show-ref refs/tags/$git_ref`" ]]; then
                 git_update_tag $git_ref
             elif [[ -n "`git show-ref refs/heads/$git_ref`" ]]; then
                 git_update_branch $git_ref
             elif [[ -n "`git show-ref refs/remotes/origin/$git_ref`" ]]; then
                 git_update_remote_branch $git_ref

             else

                 die $LINENO "$git_ref is neither branch nor tag"

             fi
 
         fi
     fi
 
     # print out the results so we know what change was used in the logs

     cd $git_dest

     git show --oneline | head -1

     cd $orig_dir

 }
 

 # A variation on git clone that lets us specify a project by it's
 # actual name, like oslo.config. This is exceptionally useful in the
 # library installation case
 function git_clone_by_name {
     local name=$1
     local repo=${GITREPO[$name]}
     local dir=${GITDIR[$name]}
     local branch=${GITBRANCH[$name]}
     git_clone $repo $dir $branch
 }
 
 

 # git can sometimes get itself infinitely stuck with transient network
 # errors or other issues with the remote end.  This wraps git in a
 # timeout/retry loop and is intended to watch over non-local git
 # processes that might hang.  GIT_TIMEOUT, if set, is passed directly
 # to timeout(1); otherwise the default value of 0 maintains the status
 # quo of waiting forever.
 # usage: git_timed <git-command>

 function git_timed {

     local count=0
     local timeout=0
 
     if [[ -n "${GIT_TIMEOUT}" ]]; then
         timeout=${GIT_TIMEOUT}
     fi
 
     until timeout -s SIGINT ${timeout} git "$@"; do
         # 124 is timeout(1)'s special return code when it reached the
         # timeout; otherwise assume fatal failure
         if [[ $? -ne 124 ]]; then
             die $LINENO "git call failed: [git $@]"
         fi
 
         count=$(($count + 1))
         warn "timeout ${count} for git call: [git $@]"
         if [ $count -eq 3 ]; then
             die $LINENO "Maximum of 3 git retries reached"
         fi
         sleep 5
     done
 }
 

 # git update using reference as a branch.
 # git_update_branch ref

 function git_update_branch {

     local git_branch=$1

     git checkout -f origin/$git_branch

     # a local branch might not exist

     git branch -D $git_branch || true
     git checkout -b $git_branch

 }
 
 # git update using reference as a branch.
 # git_update_remote_branch ref

 function git_update_remote_branch {

     local git_branch=$1

     git checkout -b $git_branch -t origin/$git_branch

 }
 
 # git update using reference as a tag. Be careful editing source at that repo
 # as working copy will be in a detached mode
 # git_update_tag ref

 function git_update_tag {

     local git_tag=$1

     git tag -d $git_tag

     # fetching given tag only

     git_timed fetch origin tag $git_tag
     git checkout -f $git_tag

 }
 
 
 # OpenStack Functions
 # ===================
 
 # Get the default value for HOST_IP
 # get_default_host_ip fixed_range floating_range host_ip_iface host_ip

 function get_default_host_ip {

     local fixed_range=$1
     local floating_range=$2
     local host_ip_iface=$3
     local host_ip=$4
 
     # Find the interface used for the default route
     host_ip_iface=${host_ip_iface:-$(ip route | sed -n '/^default/{ s/.*dev \(\w\+\)\s\+.*/\1/; p; }' | head -1)}
     # Search for an IP unless an explicit is set by ``HOST_IP`` environment variable
     if [ -z "$host_ip" -o "$host_ip" == "dhcp" ]; then
         host_ip=""

         local host_ips=$(LC_ALL=C ip -f inet addr show ${host_ip_iface} | awk '/inet/ {split($2,parts,"/");  print parts[1]}')
         local ip
         for ip in $host_ips; do

             # Attempt to filter out IP addresses that are part of the fixed and
             # floating range. Note that this method only works if the ``netaddr``
             # python library is installed. If it is not installed, an error
             # will be printed and the first IP from the interface will be used.
             # If that is not correct set ``HOST_IP`` in ``localrc`` to the correct
             # address.

             if ! (address_in_net $ip $fixed_range || address_in_net $ip $floating_range); then
                 host_ip=$ip

                 break;
             fi
         done
     fi
     echo $host_ip
 }
 

 # Generates hex string from ``size`` byte of pseudo random data
 # generate_hex_string size
 function generate_hex_string {
     local size=$1
     hexdump -n "$size" -v -e '/1 "%02x"' /dev/urandom
 }
 

 # Grab a numbered field from python prettytable output
 # Fields are numbered starting with 1
 # Reverse syntax is supported: -1 is the last field, -2 is second to last, etc.
 # get_field field-number

 function get_field {

     local data field

     while read data; do
         if [ "$1" -lt 0 ]; then
             field="(\$(NF$1))"
         else
             field="\$$(($1 + 1))"
         fi
         echo "$data" | awk -F'[ \t]*\\|[ \t]*' "{print $field}"
     done
 }
 
 # Add a policy to a policy.json file
 # Do nothing if the policy already exists
 # ``policy_add policy_file policy_name policy_permissions``

 function policy_add {

     local policy_file=$1
     local policy_name=$2
     local policy_perm=$3
 
     if grep -q ${policy_name} ${policy_file}; then
         echo "Policy ${policy_name} already exists in ${policy_file}"
         return
     fi
 
     # Add a terminating comma to policy lines without one
     # Remove the closing '}' and all lines following to the end-of-file
     local tmpfile=$(mktemp)
     uniq ${policy_file} | sed -e '
         s/]$/],/
         /^[}]/,$d
     ' > ${tmpfile}
 
     # Append policy and closing brace
     echo "    \"${policy_name}\": ${policy_perm}" >>${tmpfile}
     echo "}" >>${tmpfile}
 
     mv ${tmpfile} ${policy_file}
 }
 

 # Gets or creates a domain
 # Usage: get_or_create_domain <name> <description>
 function get_or_create_domain {

     local os_url="$KEYSTONE_SERVICE_URI_V3"

     # Gets domain id
     local domain_id=$(
         # Gets domain id
         openstack --os-token=$OS_TOKEN --os-url=$os_url \
             --os-identity-api-version=3 domain show $1 \
             -f value -c id 2>/dev/null ||
         # Creates new domain
         openstack --os-token=$OS_TOKEN --os-url=$os_url \
             --os-identity-api-version=3 domain create $1 \
             --description "$2" \
             -f value -c id
     )
     echo $domain_id
 }
 

 # Gets or creates group
 # Usage: get_or_create_group <groupname> [<domain> <description>]
 function get_or_create_group {
     local domain=${2:+--domain ${2}}
     local desc="${3:-}"
     local os_url="$KEYSTONE_SERVICE_URI_V3"
     # Gets group id
     local group_id=$(
         # Creates new group with --or-show
         openstack --os-token=$OS_TOKEN --os-url=$os_url \
             --os-identity-api-version=3 group create $1 \
             $domain --description "$desc" --or-show \
             -f value -c id
     )
     echo $group_id
 }
 

 # Gets or creates user

 # Usage: get_or_create_user <username> <password> <project> [<email> [<domain>]]

 function get_or_create_user {

     if [[ ! -z "$4" ]]; then

         local email="--email=$4"

     else

         local email=""

     fi

     local os_cmd="openstack"
     local domain=""
     if [[ ! -z "$5" ]]; then
         domain="--domain=$5"

         os_cmd="$os_cmd --os-url=$KEYSTONE_SERVICE_URI_V3 --os-identity-api-version=3"

     fi

     # Gets user id

     local user_id=$(

         # Creates new user with --or-show

         $os_cmd user create \

             $1 \
             --password "$2" \
             --project $3 \

             $email \

             $domain \

             --or-show \

             -f value -c id
     )

     echo $user_id

 }
 
 # Gets or creates project

 # Usage: get_or_create_project <name> [<domain>]

 function get_or_create_project {
     # Gets project id

     local os_cmd="openstack"
     local domain=""
     if [[ ! -z "$2" ]]; then
         domain="--domain=$2"

         os_cmd="$os_cmd --os-url=$KEYSTONE_SERVICE_URI_V3 --os-identity-api-version=3"

     fi

     local project_id=$(

         # Creates new project with --or-show
         $os_cmd project create $1 $domain --or-show -f value -c id

     )

     echo $project_id

 }
 
 # Gets or creates role
 # Usage: get_or_create_role <name>
 function get_or_create_role {

     local role_id=$(

         # Creates role with --or-show
         openstack role create $1 --or-show -f value -c id

     )

     echo $role_id

 }
 
 # Gets or adds user role
 # Usage: get_or_add_user_role <role> <user> <project>
 function get_or_add_user_role {
     # Gets user role id

     local user_role_id=$(openstack role list \
         --user $2 \

         --project $3 \
         --column "ID" \
         --column "Name" \
         | grep " $1 " | get_field 1)

     if [[ -z "$user_role_id" ]]; then

         # Adds role to user

         user_role_id=$(openstack role add \

             $1 \
             --user $2 \
             --project $3 \
             | grep " id " | get_field 2)
     fi

     echo $user_role_id

 }
 
 # Gets or creates service
 # Usage: get_or_create_service <name> <type> <description>
 function get_or_create_service {
     # Gets service id

     local service_id=$(

         # Gets service id
         openstack service show $1 -f value -c id 2>/dev/null ||
         # Creates new service if not exists
         openstack service create \

             $2 \
             --name $1 \

             --description="$3" \
             -f value -c id
     )

     echo $service_id

 }
 
 # Gets or creates endpoint
 # Usage: get_or_create_endpoint <service> <region> <publicurl> <adminurl> <internalurl>
 function get_or_create_endpoint {
     # Gets endpoint id

     local endpoint_id=$(openstack endpoint list \

         --column "ID" \
         --column "Region" \
         --column "Service Name" \
         | grep " $2 " \
         | grep " $1 " | get_field 1)

     if [[ -z "$endpoint_id" ]]; then

         # Creates new endpoint

         endpoint_id=$(openstack endpoint create \

             $1 \
             --region $2 \
             --publicurl $3 \
             --adminurl $4 \
             --internalurl $5 \
             | grep " id " | get_field 2)
     fi

     echo $endpoint_id

 }

 # Package Functions
 # =================
 
 # _get_package_dir

 function _get_package_dir {

     local pkg_dir
     if is_ubuntu; then

         pkg_dir=$FILES/debs

     elif is_fedora; then
         pkg_dir=$FILES/rpms
     elif is_suse; then
         pkg_dir=$FILES/rpms-suse
     else
         exit_distro_not_supported "list of packages"
     fi
     echo "$pkg_dir"
 }
 
 # Wrapper for ``apt-get`` to set cache and proxy environment variables
 # Uses globals ``OFFLINE``, ``*_proxy``
 # apt_get operation package [package ...]

 function apt_get {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace
 

     [[ "$OFFLINE" = "True" || -z "$@" ]] && return
     local sudo="sudo"
     [[ "$(id -u)" = "0" ]] && sudo="env"

 
     $xtrace

     $sudo DEBIAN_FRONTEND=noninteractive \

         http_proxy=${http_proxy:-} https_proxy=${https_proxy:-} \
         no_proxy=${no_proxy:-} \

         apt-get --option "Dpkg::Options::=--force-confold" --assume-yes "$@"
 }
 
 # get_packages() collects a list of package names of any type from the

 # prerequisite files in ``files/{debs|rpms}``.  The list is intended

 # to be passed to a package installer such as apt or yum.
 #
 # Only packages required for the services in 1st argument will be
 # included.  Two bits of metadata are recognized in the prerequisite files:
 #
 # - ``# NOPRIME`` defers installation to be performed later in `stack.sh`
 # - ``# dist:DISTRO`` or ``dist:DISTRO1,DISTRO2`` limits the selection
 #   of the package to the distros listed.  The distro names are case insensitive.

 function get_packages {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local services=$@
     local package_dir=$(_get_package_dir)

     local file_to_parse=""
     local service=""

     INSTALL_TESTONLY_PACKAGES=$(trueorfalse False INSTALL_TESTONLY_PACKAGES)

     if [[ -z "$package_dir" ]]; then
         echo "No package directory supplied"
         return 1
     fi
     if [[ -z "$DISTRO" ]]; then
         GetDistro
     fi
     for service in ${services//,/ }; do
         # Allow individual services to specify dependencies
         if [[ -e ${package_dir}/${service} ]]; then
             file_to_parse="${file_to_parse} $service"
         fi
         # NOTE(sdague) n-api needs glance for now because that's where
         # glance client is
         if [[ $service == n-api ]]; then
             if [[ ! $file_to_parse =~ nova ]]; then
                 file_to_parse="${file_to_parse} nova"
             fi
             if [[ ! $file_to_parse =~ glance ]]; then
                 file_to_parse="${file_to_parse} glance"
             fi
         elif [[ $service == c-* ]]; then
             if [[ ! $file_to_parse =~ cinder ]]; then
                 file_to_parse="${file_to_parse} cinder"
             fi
         elif [[ $service == ceilometer-* ]]; then
             if [[ ! $file_to_parse =~ ceilometer ]]; then
                 file_to_parse="${file_to_parse} ceilometer"
             fi
         elif [[ $service == s-* ]]; then
             if [[ ! $file_to_parse =~ swift ]]; then
                 file_to_parse="${file_to_parse} swift"
             fi
         elif [[ $service == n-* ]]; then
             if [[ ! $file_to_parse =~ nova ]]; then
                 file_to_parse="${file_to_parse} nova"
             fi
         elif [[ $service == g-* ]]; then
             if [[ ! $file_to_parse =~ glance ]]; then
                 file_to_parse="${file_to_parse} glance"
             fi
         elif [[ $service == key* ]]; then
             if [[ ! $file_to_parse =~ keystone ]]; then
                 file_to_parse="${file_to_parse} keystone"
             fi
         elif [[ $service == q-* ]]; then
             if [[ ! $file_to_parse =~ neutron ]]; then
                 file_to_parse="${file_to_parse} neutron"
             fi

         elif [[ $service == ir-* ]]; then
             if [[ ! $file_to_parse =~ ironic ]]; then
                 file_to_parse="${file_to_parse} ironic"
             fi

         fi
     done
 
     for file in ${file_to_parse}; do
         local fname=${package_dir}/${file}
         local OIFS line package distros distro
         [[ -e $fname ]] || continue
 
         OIFS=$IFS
         IFS=$'\n'
         for line in $(<${fname}); do
             if [[ $line =~ "NOPRIME" ]]; then
                 continue
             fi
 
             # Assume we want this package
             package=${line%#*}
             inst_pkg=1
 
             # Look for # dist:xxx in comment
             if [[ $line =~ (.*)#.*dist:([^ ]*) ]]; then
                 # We are using BASH regexp matching feature.
                 package=${BASH_REMATCH[1]}
                 distros=${BASH_REMATCH[2]}
                 # In bash ${VAR,,} will lowecase VAR
                 # Look for a match in the distro list
                 if [[ ! ${distros,,} =~ ${DISTRO,,} ]]; then
                     # If no match then skip this package
                     inst_pkg=0
                 fi
             fi
 
             # Look for # testonly in comment
             if [[ $line =~ (.*)#.*testonly.* ]]; then
                 package=${BASH_REMATCH[1]}
                 # Are we installing test packages? (test for the default value)
                 if [[ $INSTALL_TESTONLY_PACKAGES = "False" ]]; then
                     # If not installing test packages the skip this package
                     inst_pkg=0
                 fi
             fi
 
             if [[ $inst_pkg = 1 ]]; then
                 echo $package
             fi
         done
         IFS=$OIFS
     done

     $xtrace

 }
 
 # Distro-agnostic package installer

 # Uses globals ``NO_UPDATE_REPOS``, ``REPOS_UPDATED``, ``RETRY_UPDATE``

 # install_package package [package ...]

 function update_package_repo {

     NO_UPDATE_REPOS=${NO_UPDATE_REPOS:-False}
     REPOS_UPDATED=${REPOS_UPDATED:-False}
     RETRY_UPDATE=${RETRY_UPDATE:-False}
 

     if [[ "$NO_UPDATE_REPOS" = "True" ]]; then

         return 0
     fi

     if is_ubuntu; then
         local xtrace=$(set +o | grep xtrace)
         set +o xtrace
         if [[ "$REPOS_UPDATED" != "True" || "$RETRY_UPDATE" = "True" ]]; then
             # if there are transient errors pulling the updates, that's fine.
             # It may be secondary repositories that we don't really care about.
             apt_get update  || /bin/true
             REPOS_UPDATED=True
         fi

         $xtrace

     fi
 }
 
 function real_install_package {
     if is_ubuntu; then

         apt_get install "$@"
     elif is_fedora; then
         yum_install "$@"
     elif is_suse; then
         zypper_install "$@"
     else
         exit_distro_not_supported "installing packages"
     fi
 }
 

 # Distro-agnostic package installer
 # install_package package [package ...]
 function install_package {
     update_package_repo
     real_install_package $@ || RETRY_UPDATE=True update_package_repo && real_install_package $@
 }
 

 # Distro-agnostic function to tell if a package is installed
 # is_package_installed package [package ...]

 function is_package_installed {

     if [[ -z "$@" ]]; then
         return 1
     fi
 
     if [[ -z "$os_PACKAGE" ]]; then
         GetOSVersion
     fi
 
     if [[ "$os_PACKAGE" = "deb" ]]; then
         dpkg -s "$@" > /dev/null 2> /dev/null
     elif [[ "$os_PACKAGE" = "rpm" ]]; then
         rpm --quiet -q "$@"
     else
         exit_distro_not_supported "finding if a package is installed"
     fi
 }
 
 # Distro-agnostic package uninstaller
 # uninstall_package package [package ...]

 function uninstall_package {

     if is_ubuntu; then
         apt_get purge "$@"
     elif is_fedora; then

         sudo $YUM remove -y "$@" ||:

     elif is_suse; then
         sudo zypper rm "$@"
     else
         exit_distro_not_supported "uninstalling packages"
     fi
 }
 
 # Wrapper for ``yum`` to set proxy environment variables

 # Uses globals ``OFFLINE``, ``*_proxy``, ``YUM``

 # yum_install package [package ...]

 function yum_install {

     [[ "$OFFLINE" = "True" ]] && return
     local sudo="sudo"
     [[ "$(id -u)" = "0" ]] && sudo="env"

 
     # The manual check for missing packages is because yum -y assumes
     # missing packages are OK.  See
     # https://bugzilla.redhat.com/show_bug.cgi?id=965567

     $sudo http_proxy=$http_proxy https_proxy=$https_proxy \
         no_proxy=$no_proxy \

         $YUM install -y "$@" 2>&1 | \

         awk '
             BEGIN { fail=0 }
             /No package/ { fail=1 }
             { print }
             END { exit fail }' || \
                 die $LINENO "Missing packages detected"
 
     # also ensure we catch a yum failure
     if [[ ${PIPESTATUS[0]} != 0 ]]; then

         die $LINENO "$YUM install failure"

     fi

 }
 
 # zypper wrapper to set arguments correctly

 # Uses globals ``OFFLINE``, ``*_proxy``

 # zypper_install package [package ...]

 function zypper_install {

     [[ "$OFFLINE" = "True" ]] && return
     local sudo="sudo"
     [[ "$(id -u)" = "0" ]] && sudo="env"
     $sudo http_proxy=$http_proxy https_proxy=$https_proxy \
         zypper --non-interactive install --auto-agree-with-licenses "$@"
 }
 
 
 # Process Functions
 # =================
 
 # _run_process() is designed to be backgrounded by run_process() to simulate a
 # fork.  It includes the dirty work of closing extra filehandles and preparing log
 # files to produce the same logs as screen_it().  The log filename is derived

 # from the service name.
 # Uses globals ``CURRENT_LOG_TIME``, ``LOGDIR``, ``SCREEN_LOGDIR``, ``SCREEN_NAME``, ``SERVICE_DIR``

 # If an optional group is provided sg will be used to set the group of
 # the command.
 # _run_process service "command-line" [group]

 function _run_process {

     local service=$1
     local command="$2"

     local group=$3

 
     # Undo logging redirections and close the extra descriptors
     exec 1>&3
     exec 2>&3
     exec 3>&-
     exec 6>&-
 

     local real_logfile="${LOGDIR}/${service}.log.${CURRENT_LOG_TIME}"
     if [[ -n ${LOGDIR} ]]; then
         exec 1>&"$real_logfile" 2>&1
         ln -sf "$real_logfile" ${LOGDIR}/${service}.log
         if [[ -n ${SCREEN_LOGDIR} ]]; then
             # Drop the backward-compat symlink
             ln -sf "$real_logfile" ${SCREEN_LOGDIR}/screen-${service}.log
         fi

 
         # TODO(dtroyer): Hack to get stdout from the Python interpreter for the logs.
         export PYTHONUNBUFFERED=1
     fi
 

     # Run under ``setsid`` to force the process to become a session and group leader.
     # The pid saved can be used with pkill -g to get the entire process group.

     if [[ -n "$group" ]]; then
         setsid sg $group "$command" & echo $! >$SERVICE_DIR/$SCREEN_NAME/$service.pid
     else
         setsid $command & echo $! >$SERVICE_DIR/$SCREEN_NAME/$service.pid
     fi

 
     # Just silently exit this process
     exit 0

 }
 
 # Helper to remove the ``*.failure`` files under ``$SERVICE_DIR/$SCREEN_NAME``.
 # This is used for ``service_check`` when all the ``screen_it`` are called finished

 # Uses globals ``SCREEN_NAME``, ``SERVICE_DIR``

 # init_service_check

 function init_service_check {

     SCREEN_NAME=${SCREEN_NAME:-stack}
     SERVICE_DIR=${SERVICE_DIR:-${DEST}/status}
 
     if [[ ! -d "$SERVICE_DIR/$SCREEN_NAME" ]]; then
         mkdir -p "$SERVICE_DIR/$SCREEN_NAME"
     fi
 
     rm -f "$SERVICE_DIR/$SCREEN_NAME"/*.failure
 }
 
 # Find out if a process exists by partial name.
 # is_running name

 function is_running {

     local name=$1
     ps auxw | grep -v grep | grep ${name} > /dev/null

     local exitcode=$?

     # some times I really hate bash reverse binary logic

     return $exitcode

 }
 

 # Run a single service under screen or directly
 # If the command includes shell metachatacters (;<>*) it must be run using a shell

 # If an optional group is provided sg will be used to run the
 # command as that group.
 # run_process service "command-line" [group]

 function run_process {

     local service=$1
     local command="$2"

     local group=$3

     if is_service_enabled $service; then
         if [[ "$USE_SCREEN" = "True" ]]; then

             screen_process "$service" "$command" "$group"

         else
             # Spawn directly without screen

             _run_process "$service" "$command" "$group" &

         fi
     fi

 }
 

 # Helper to launch a process in a named screen

 # Uses globals ``CURRENT_LOG_TIME``, ```LOGDIR``, ``SCREEN_LOGDIR``, `SCREEN_NAME``,

 # ``SERVICE_DIR``, ``USE_SCREEN``

 # screen_process name "command-line" [group]

 # Run a command in a shell in a screen window, if an optional group
 # is provided, use sg to set the group of the command.

 function screen_process {
     local name=$1

     local command="$2"

     local group=$3

     SCREEN_NAME=${SCREEN_NAME:-stack}
     SERVICE_DIR=${SERVICE_DIR:-${DEST}/status}

     USE_SCREEN=$(trueorfalse True USE_SCREEN)

     # Append the process to the screen rc file
     screen_rc "$name" "$command"

     screen -S $SCREEN_NAME -X screen -t $name

     local real_logfile="${LOGDIR}/${name}.log.${CURRENT_LOG_TIME}"
     echo "LOGDIR: $LOGDIR"
     echo "SCREEN_LOGDIR: $SCREEN_LOGDIR"
     echo "log: $real_logfile"
     if [[ -n ${LOGDIR} ]]; then
         screen -S $SCREEN_NAME -p $name -X logfile "$real_logfile"

         screen -S $SCREEN_NAME -p $name -X log on

         ln -sf "$real_logfile" ${LOGDIR}/${name}.log
         if [[ -n ${SCREEN_LOGDIR} ]]; then
             # Drop the backward-compat symlink
             ln -sf "$real_logfile" ${SCREEN_LOGDIR}/screen-${1}.log
         fi

     fi

     # sleep to allow bash to be ready to be send the command - we are
     # creating a new window in screen and then sends characters, so if
     # bash isn't running by the time we send the command, nothing happens
     sleep 3
 
     NL=`echo -ne '\015'`
     # This fun command does the following:
     # - the passed server command is backgrounded
     # - the pid of the background process is saved in the usual place
     # - the server process is brought back to the foreground
     # - if the server process exits prematurely the fg command errors
     # and a message is written to stdout and the process failure file
     #
     # The pid saved can be used in stop_process() as a process group
     # id to kill off all child processes
     if [[ -n "$group" ]]; then
         command="sg $group '$command'"

     fi

     screen -S $SCREEN_NAME -p $name -X stuff "$command & echo \$! >$SERVICE_DIR/$SCREEN_NAME/${name}.pid; fg || echo \"$name failed to start\" | tee \"$SERVICE_DIR/$SCREEN_NAME/${name}.failure\"$NL"

 }
 
 # Screen rc file builder

 # Uses globals ``SCREEN_NAME``, ``SCREENRC``

 # screen_rc service "command-line"
 function screen_rc {
     SCREEN_NAME=${SCREEN_NAME:-stack}
     SCREENRC=$TOP_DIR/$SCREEN_NAME-screenrc
     if [[ ! -e $SCREENRC ]]; then
         # Name the screen session
         echo "sessionname $SCREEN_NAME" > $SCREENRC
         # Set a reasonable statusbar
         echo "hardstatus alwayslastline '$SCREEN_HARDSTATUS'" >> $SCREENRC
         # Some distributions override PROMPT_COMMAND for the screen terminal type - turn that off
         echo "setenv PROMPT_COMMAND /bin/true" >> $SCREENRC
         echo "screen -t shell bash" >> $SCREENRC
     fi
     # If this service doesn't already exist in the screenrc file
     if ! grep $1 $SCREENRC 2>&1 > /dev/null; then
         NL=`echo -ne '\015'`
         echo "screen -t $1 bash" >> $SCREENRC
         echo "stuff \"$2$NL\"" >> $SCREENRC
 

         if [[ -n ${LOGDIR} ]]; then
             echo "logfile ${LOGDIR}/${1}.log.${CURRENT_LOG_TIME}" >>$SCREENRC

             echo "log on" >>$SCREENRC
         fi
     fi
 }
 
 # Stop a service in screen
 # If a PID is available use it, kill the whole process group via TERM
 # If screen is being used kill the screen window; this will catch processes
 # that did not leave a PID behind

 # Uses globals ``SCREEN_NAME``, ``SERVICE_DIR``, ``USE_SCREEN``

 # screen_stop_service service

 function screen_stop_service {
     local service=$1
 

     SCREEN_NAME=${SCREEN_NAME:-stack}
     SERVICE_DIR=${SERVICE_DIR:-${DEST}/status}

     USE_SCREEN=$(trueorfalse True USE_SCREEN)

     if is_service_enabled $service; then
         # Clean up the screen window
         screen -S $SCREEN_NAME -p $service -X kill
     fi
 }
 
 # Stop a service process
 # If a PID is available use it, kill the whole process group via TERM
 # If screen is being used kill the screen window; this will catch processes
 # that did not leave a PID behind
 # Uses globals ``SERVICE_DIR``, ``USE_SCREEN``
 # stop_process service
 function stop_process {
     local service=$1
 
     SERVICE_DIR=${SERVICE_DIR:-${DEST}/status}

     USE_SCREEN=$(trueorfalse True USE_SCREEN)

 
     if is_service_enabled $service; then

         # Kill via pid if we have one available

         if [[ -r $SERVICE_DIR/$SCREEN_NAME/$service.pid ]]; then
             pkill -g $(cat $SERVICE_DIR/$SCREEN_NAME/$service.pid)
             rm $SERVICE_DIR/$SCREEN_NAME/$service.pid

         fi
         if [[ "$USE_SCREEN" = "True" ]]; then
             # Clean up the screen window

             screen_stop_service $service

         fi
     fi
 }
 
 # Helper to get the status of each running service

 # Uses globals ``SCREEN_NAME``, ``SERVICE_DIR``

 # service_check

 function service_check {

     local service
     local failures
     SCREEN_NAME=${SCREEN_NAME:-stack}
     SERVICE_DIR=${SERVICE_DIR:-${DEST}/status}
 
 
     if [[ ! -d "$SERVICE_DIR/$SCREEN_NAME" ]]; then
         echo "No service status directory found"
         return
     fi
 
     # Check if there is any falure flag file under $SERVICE_DIR/$SCREEN_NAME

     # make this -o errexit safe
     failures=`ls "$SERVICE_DIR/$SCREEN_NAME"/*.failure 2>/dev/null || /bin/true`

 
     for service in $failures; do
         service=`basename $service`
         service=${service%.failure}
         echo "Error: Service $service is not running"
     done
 
     if [ -n "$failures" ]; then

         die $LINENO "More details about the above errors can be found with screen, with ./rejoin-stack.sh"

     fi
 }
 

 # Tail a log file in a screen if USE_SCREEN is true.
 function tail_log {

     local name=$1

     local logfile=$2
 

     USE_SCREEN=$(trueorfalse True USE_SCREEN)

     if [[ "$USE_SCREEN" = "True" ]]; then

         screen_process "$name" "sudo tail -f $logfile"

     fi
 }
 

 # Deprecated Functions
 # --------------------
 
 # _old_run_process() is designed to be backgrounded by old_run_process() to simulate a
 # fork.  It includes the dirty work of closing extra filehandles and preparing log
 # files to produce the same logs as screen_it().  The log filename is derived
 # from the service name and global-and-now-misnamed ``SCREEN_LOGDIR``
 # Uses globals ``CURRENT_LOG_TIME``, ``SCREEN_LOGDIR``, ``SCREEN_NAME``, ``SERVICE_DIR``
 # _old_run_process service "command-line"
 function _old_run_process {
     local service=$1
     local command="$2"
 
     # Undo logging redirections and close the extra descriptors
     exec 1>&3
     exec 2>&3
     exec 3>&-
     exec 6>&-
 
     if [[ -n ${SCREEN_LOGDIR} ]]; then

         exec 1>&${SCREEN_LOGDIR}/screen-${1}.log.${CURRENT_LOG_TIME} 2>&1
         ln -sf ${SCREEN_LOGDIR}/screen-${1}.log.${CURRENT_LOG_TIME} ${SCREEN_LOGDIR}/screen-${1}.log

 
         # TODO(dtroyer): Hack to get stdout from the Python interpreter for the logs.
         export PYTHONUNBUFFERED=1
     fi
 
     exec /bin/bash -c "$command"
     die "$service exec failure: $command"
 }
 
 # old_run_process() launches a child process that closes all file descriptors and
 # then exec's the passed in command.  This is meant to duplicate the semantics
 # of screen_it() without screen.  PIDs are written to
 # ``$SERVICE_DIR/$SCREEN_NAME/$service.pid`` by the spawned child process.
 # old_run_process service "command-line"
 function old_run_process {
     local service=$1
     local command="$2"
 
     # Spawn the child process
     _old_run_process "$service" "$command" &
     echo $!
 }
 
 # Compatibility for existing start_XXXX() functions
 # Uses global ``USE_SCREEN``
 # screen_it service "command-line"
 function screen_it {
     if is_service_enabled $1; then
         # Append the service to the screen rc file
         screen_rc "$1" "$2"
 
         if [[ "$USE_SCREEN" = "True" ]]; then

             screen_process "$1" "$2"

         else
             # Spawn directly without screen
             old_run_process "$1" "$2" >$SERVICE_DIR/$SCREEN_NAME/$1.pid
         fi
     fi
 }
 
 # Compatibility for existing stop_XXXX() functions
 # Stop a service in screen
 # If a PID is available use it, kill the whole process group via TERM
 # If screen is being used kill the screen window; this will catch processes
 # that did not leave a PID behind
 # screen_stop service
 function screen_stop {
     # Clean up the screen window
     stop_process $1
 }
 
 

 # Python Functions
 # ================
 
 # Get the path to the pip command.
 # get_pip_command

 function get_pip_command {

     which pip || which pip-python
 
     if [ $? -ne 0 ]; then
         die $LINENO "Unable to find pip; cannot continue"
     fi
 }
 
 # Get the path to the direcotry where python executables are installed.
 # get_python_exec_prefix

 function get_python_exec_prefix {

     if is_fedora || is_suse; then
         echo "/usr/bin"
     else
         echo "/usr/local/bin"
     fi
 }
 
 # Wrapper for ``pip install`` to set cache and proxy environment variables

 # Uses globals ``OFFLINE``, ``TRACK_DEPENDS``, ``*_proxy``

 # pip_install package [package ...]
 function pip_install {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local offline=${OFFLINE:-False}
     if [[ "$offline" == "True" || -z "$@" ]]; then

         $xtrace
         return
     fi
 

     if [[ -z "$os_PACKAGE" ]]; then
         GetOSVersion
     fi

     if [[ $TRACK_DEPENDS = True && ! "$@" =~ virtualenv ]]; then
         # TRACK_DEPENDS=True installation creates a circular dependency when
         # we attempt to install virtualenv into a virualenv, so we must global
         # that installation.

         source $DEST/.venv/bin/activate

         local cmd_pip=$DEST/.venv/bin/pip
         local sudo_pip="env"

     else

         local cmd_pip=$(get_pip_command)

         local sudo_pip="sudo -H"

     fi
 

     local pip_version=$(python -c "import pip; \
                         print(pip.__version__.strip('.')[0])")
     if (( pip_version<6 )); then
         die $LINENO "Currently installed pip version ${pip_version} does not" \
             "meet minimum requirements (>=6)."
     fi
 

     $xtrace

     $sudo_pip \

         http_proxy=${http_proxy:-} \
         https_proxy=${https_proxy:-} \
         no_proxy=${no_proxy:-} \

         $cmd_pip install \

         $@

     INSTALL_TESTONLY_PACKAGES=$(trueorfalse False INSTALL_TESTONLY_PACKAGES)

     if [[ "$INSTALL_TESTONLY_PACKAGES" == "True" ]]; then
         local test_req="$@/test-requirements.txt"
         if [[ -e "$test_req" ]]; then

             $sudo_pip \

                 http_proxy=${http_proxy:-} \
                 https_proxy=${https_proxy:-} \
                 no_proxy=${no_proxy:-} \

                 $cmd_pip install \

                 -r $test_req

         fi
     fi

 }
 

 # should we use this library from their git repo, or should we let it
 # get pulled in via pip dependencies.
 function use_library_from_git {
     local name=$1
     local enabled=1
     [[ ,${LIBS_FROM_GIT}, =~ ,${name}, ]] && enabled=0
     return $enabled
 }
 
 # setup a library by name. If we are trying to use the library from
 # git, we'll do a git based install, otherwise we'll punt and the
 # library should be installed by a requirements pull from another
 # project.
 function setup_lib {
     local name=$1
     local dir=${GITDIR[$name]}
     setup_install $dir
 }
 

 # setup a library by name in editiable mode. If we are trying to use
 # the library from git, we'll do a git based install, otherwise we'll
 # punt and the library should be installed by a requirements pull from
 # another project.
 #
 # use this for non namespaced libraries
 function setup_dev_lib {
     local name=$1
     local dir=${GITDIR[$name]}
     setup_develop $dir
 }

 # this should be used if you want to install globally, all libraries should
 # use this, especially *oslo* ones
 function setup_install {
     local project_dir=$1
     setup_package_with_req_sync $project_dir
 }
 
 # this should be used for projects which run services, like all services
 function setup_develop {
     local project_dir=$1
     setup_package_with_req_sync $project_dir -e
 }
 

 # determine if a project as specified by directory is in
 # projects.txt. This will not be an exact match because we throw away
 # the namespacing when we clone, but it should be good enough in all
 # practical ways.
 function is_in_projects_txt {
     local project_dir=$1
     local project_name=$(basename $project_dir)
     return grep "/$project_name\$" $REQUIREMENTS_DIR/projects.txt >/dev/null
 }
 

 # ``pip install -e`` the package, which processes the dependencies
 # using pip before running `setup.py develop`
 #
 # Updates the dependencies in project_dir from the
 # openstack/requirements global list before installing anything.
 #
 # Uses globals ``TRACK_DEPENDS``, ``REQUIREMENTS_DIR``, ``UNDO_REQUIREMENTS``
 # setup_develop directory

 function setup_package_with_req_sync {

     local project_dir=$1

     local flags=$2

 
     # Don't update repo if local changes exist
     # Don't use buggy "git diff --quiet"

     # ``errexit`` requires us to trap the exit code when the repo is changed
     local update_requirements=$(cd $project_dir && git diff --exit-code >/dev/null || echo "changed")

     if [[ $update_requirements != "changed" ]]; then

         if [[ "$REQUIREMENTS_MODE" == "soft" ]]; then
             if is_in_projects_txt $project_dir; then
                 (cd $REQUIREMENTS_DIR; \
                     python update.py $project_dir)
             else
                 # soft update projects not found in requirements project.txt
                 (cd $REQUIREMENTS_DIR; \
                     python update.py -s $project_dir)
             fi
         else
             (cd $REQUIREMENTS_DIR; \
                 python update.py $project_dir)
         fi

     fi
 

     setup_package $project_dir $flags

 
     # We've just gone and possibly modified the user's source tree in an
     # automated way, which is considered bad form if it's a development
     # tree because we've screwed up their next git checkin. So undo it.
     #
     # However... there are some circumstances, like running in the gate
     # where we really really want the overridden version to stick. So provide
     # a variable that tells us whether or not we should UNDO the requirements
     # changes (this will be set to False in the OpenStack ci gate)
     if [ $UNDO_REQUIREMENTS = "True" ]; then

         if [[ $update_requirements != "changed" ]]; then

             (cd $project_dir && git reset --hard)
         fi
     fi
 }
 
 # ``pip install -e`` the package, which processes the dependencies
 # using pip before running `setup.py develop`
 # Uses globals ``STACK_USER``
 # setup_develop_no_requirements_update directory

 function setup_package {

     local project_dir=$1

     local flags=$2

     pip_install $flags $project_dir

     # ensure that further actions can do things like setup.py sdist

     if [[ "$flags" == "-e" ]]; then
         safe_chown -R $STACK_USER $1/*.egg-info
     fi

 }
 

 # Plugin Functions
 # =================
 
 DEVSTACK_PLUGINS=${DEVSTACK_PLUGINS:-""}
 
 # enable_plugin <name> <url> [branch]
 #
 # ``name`` is an arbitrary name - (aka: glusterfs, nova-docker, zaqar)
 # ``url`` is a git url
 # ``branch`` is a gitref. If it's not set, defaults to master
 function enable_plugin {
     local name=$1
     local url=$2
     local branch=${3:-master}
     DEVSTACK_PLUGINS+=",$name"
     GITREPO[$name]=$url
     GITDIR[$name]=$DEST/$name
     GITBRANCH[$name]=$branch
 }
 
 # fetch_plugins
 #
 # clones all plugins
 function fetch_plugins {
     local plugins="${DEVSTACK_PLUGINS}"
     local plugin
 
     # short circuit if nothing to do
     if [[ -z $plugins ]]; then
         return
     fi
 
     echo "Fetching devstack plugins"
     for plugin in ${plugins//,/ }; do
         git_clone_by_name $plugin
     done
 }
 
 # load_plugin_settings
 #
 # Load settings from plugins in the order that they were registered
 function load_plugin_settings {
     local plugins="${DEVSTACK_PLUGINS}"
     local plugin
 
     # short circuit if nothing to do
     if [[ -z $plugins ]]; then
         return
     fi
 
     echo "Loading plugin settings"
     for plugin in ${plugins//,/ }; do
         local dir=${GITDIR[$plugin]}
         # source any known settings
         if [[ -f $dir/devstack/settings ]]; then
             source $dir/devstack/settings
         fi
     done
 }
 
 # run_plugins
 #
 # Run the devstack/plugin.sh in all the plugin directories. These are
 # run in registration order.
 function run_plugins {
     local mode=$1
     local phase=$2

 
     local plugins="${DEVSTACK_PLUGINS}"
     local plugin

     for plugin in ${plugins//,/ }; do
         local dir=${GITDIR[$plugin]}
         if [[ -f $dir/devstack/plugin.sh ]]; then
             source $dir/devstack/plugin.sh $mode $phase
         fi
     done
 }
 
 function run_phase {
     local mode=$1
     local phase=$2
     if [[ -d $TOP_DIR/extras.d ]]; then
         for i in $TOP_DIR/extras.d/*.sh; do
             [[ -r $i ]] && source $i $mode $phase
         done
     fi
     # the source phase corresponds to settings loading in plugins
     if [[ "$mode" == "source" ]]; then
         load_plugin_settings
     else
         run_plugins $mode $phase
     fi
 }
 

 
 # Service Functions
 # =================
 
 # remove extra commas from the input string (i.e. ``ENABLED_SERVICES``)
 # _cleanup_service_list service-list

 function _cleanup_service_list {

     echo "$1" | sed -e '
         s/,,/,/g;
         s/^,//;
         s/,$//
     '
 }
 
 # disable_all_services() removes all current services
 # from ``ENABLED_SERVICES`` to reset the configuration
 # before a minimal installation
 # Uses global ``ENABLED_SERVICES``
 # disable_all_services

 function disable_all_services {

     ENABLED_SERVICES=""
 }
 
 # Remove all services starting with '-'.  For example, to install all default
 # services except rabbit (rabbit) set in ``localrc``:
 # ENABLED_SERVICES+=",-rabbit"
 # Uses global ``ENABLED_SERVICES``
 # disable_negated_services

 function disable_negated_services {

     local tmpsvcs="${ENABLED_SERVICES}"
     local service
     for service in ${tmpsvcs//,/ }; do
         if [[ ${service} == -* ]]; then
             tmpsvcs=$(echo ${tmpsvcs}|sed -r "s/(,)?(-)?${service#-}(,)?/,/g")
         fi
     done
     ENABLED_SERVICES=$(_cleanup_service_list "$tmpsvcs")
 }
 
 # disable_service() removes the services passed as argument to the
 # ``ENABLED_SERVICES`` list, if they are present.
 #
 # For example:
 #   disable_service rabbit
 #
 # This function does not know about the special cases
 # for nova, glance, and neutron built into is_service_enabled().
 # Uses global ``ENABLED_SERVICES``
 # disable_service service [service ...]

 function disable_service {

     local tmpsvcs=",${ENABLED_SERVICES},"
     local service
     for service in $@; do
         if is_service_enabled $service; then
             tmpsvcs=${tmpsvcs//,$service,/,}
         fi
     done
     ENABLED_SERVICES=$(_cleanup_service_list "$tmpsvcs")
 }
 
 # enable_service() adds the services passed as argument to the
 # ``ENABLED_SERVICES`` list, if they are not already present.
 #
 # For example:
 #   enable_service qpid
 #
 # This function does not know about the special cases
 # for nova, glance, and neutron built into is_service_enabled().
 # Uses global ``ENABLED_SERVICES``
 # enable_service service [service ...]

 function enable_service {

     local tmpsvcs="${ENABLED_SERVICES}"

     local service

     for service in $@; do
         if ! is_service_enabled $service; then
             tmpsvcs+=",$service"
         fi
     done
     ENABLED_SERVICES=$(_cleanup_service_list "$tmpsvcs")
     disable_negated_services
 }
 
 # is_service_enabled() checks if the service(s) specified as arguments are
 # enabled by the user in ``ENABLED_SERVICES``.
 #
 # Multiple services specified as arguments are ``OR``'ed together; the test
 # is a short-circuit boolean, i.e it returns on the first match.
 #
 # There are special cases for some 'catch-all' services::
 #   **nova** returns true if any service enabled start with **n-**
 #   **cinder** returns true if any service enabled start with **c-**
 #   **ceilometer** returns true if any service enabled start with **ceilometer**
 #   **glance** returns true if any service enabled start with **g-**
 #   **neutron** returns true if any service enabled start with **q-**
 #   **swift** returns true if any service enabled start with **s-**
 #   **trove** returns true if any service enabled start with **tr-**
 #   For backward compatibility if we have **swift** in ENABLED_SERVICES all the
 #   **s-** services will be enabled. This will be deprecated in the future.
 #
 # Cells within nova is enabled if **n-cell** is in ``ENABLED_SERVICES``.
 # We also need to make sure to treat **n-cell-region** and **n-cell-child**
 # as enabled in this case.
 #
 # Uses global ``ENABLED_SERVICES``
 # is_service_enabled service [service ...]

 function is_service_enabled {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace
     local enabled=1

     local services=$@
     local service

     for service in ${services}; do

         [[ ,${ENABLED_SERVICES}, =~ ,${service}, ]] && enabled=0

 
         # Look for top-level 'enabled' function for this service
         if type is_${service}_enabled >/dev/null 2>&1; then
             # A function exists for this service, use it
             is_${service}_enabled

             enabled=$?

         fi
 
         # TODO(dtroyer): Remove these legacy special-cases after the is_XXX_enabled()
         #                are implemented
 

         [[ ${service} == n-cell-* && ${ENABLED_SERVICES} =~ "n-cell" ]] && enabled=0

         [[ ${service} == n-cpu-* && ${ENABLED_SERVICES} =~ "n-cpu" ]] && enabled=0

         [[ ${service} == "nova" && ${ENABLED_SERVICES} =~ "n-" ]] && enabled=0
         [[ ${service} == "cinder" && ${ENABLED_SERVICES} =~ "c-" ]] && enabled=0
         [[ ${service} == "ceilometer" && ${ENABLED_SERVICES} =~ "ceilometer-" ]] && enabled=0
         [[ ${service} == "glance" && ${ENABLED_SERVICES} =~ "g-" ]] && enabled=0
         [[ ${service} == "ironic" && ${ENABLED_SERVICES} =~ "ir-" ]] && enabled=0
         [[ ${service} == "neutron" && ${ENABLED_SERVICES} =~ "q-" ]] && enabled=0
         [[ ${service} == "trove" && ${ENABLED_SERVICES} =~ "tr-" ]] && enabled=0
         [[ ${service} == "swift" && ${ENABLED_SERVICES} =~ "s-" ]] && enabled=0
         [[ ${service} == s-* && ${ENABLED_SERVICES} =~ "swift" ]] && enabled=0

         [[ ${service} == key-* && ${ENABLED_SERVICES} =~ "key" ]] && enabled=0

     done

     $xtrace
     return $enabled

 }
 
 # Toggle enable/disable_service for services that must run exclusive of each other
 #  $1 The name of a variable containing a space-separated list of services
 #  $2 The name of a variable in which to store the enabled service's name
 #  $3 The name of the service to enable
 function use_exclusive_service {
     local options=${!1}
     local selection=$3

     local out=$2

     [ -z $selection ] || [[ ! "$options" =~ "$selection" ]] && return 1

     local opt

     for opt in $options;do
         [[ "$opt" = "$selection" ]] && enable_service $opt || disable_service $opt
     done
     eval "$out=$selection"
     return 0
 }
 
 

 # System Functions
 # ================

 
 # Only run the command if the target file (the last arg) is not on an
 # NFS filesystem.

 function _safe_permission_operation {

     local xtrace=$(set +o | grep xtrace)
     set +o xtrace

     local args=( $@ )
     local last
     local sudo_cmd
     local dir_to_check
 
     let last="${#args[*]} - 1"
 

     local dir_to_check=${args[$last]}

     if [ ! -d "$dir_to_check" ]; then
         dir_to_check=`dirname "$dir_to_check"`
     fi
 
     if is_nfs_directory "$dir_to_check" ; then

         $xtrace

         return 0
     fi
 
     if [[ $TRACK_DEPENDS = True ]]; then
         sudo_cmd="env"
     else
         sudo_cmd="sudo"
     fi
 

     $xtrace

     $sudo_cmd $@
 }
 
 # Exit 0 if address is in network or 1 if address is not in network
 # ip-range is in CIDR notation: 1.2.3.4/20
 # address_in_net ip-address ip-range

 function address_in_net {

     local ip=$1
     local range=$2
     local masklen=${range#*/}
     local network=$(maskip ${range%/*} $(cidr2netmask $masklen))
     local subnet=$(maskip $ip $(cidr2netmask $masklen))
     [[ $network == $subnet ]]
 }
 
 # Add a user to a group.
 # add_user_to_group user group

 function add_user_to_group {

     local user=$1
     local group=$2
 
     if [[ -z "$os_VENDOR" ]]; then
         GetOSVersion
     fi
 
     # SLE11 and openSUSE 12.2 don't have the usual usermod
     if ! is_suse || [[ "$os_VENDOR" = "openSUSE" && "$os_RELEASE" != "12.2" ]]; then
         sudo usermod -a -G "$group" "$user"
     else
         sudo usermod -A "$group" "$user"
     fi
 }
 
 # Convert CIDR notation to a IPv4 netmask
 # cidr2netmask cidr-bits

 function cidr2netmask {

     local maskpat="255 255 255 255"
     local maskdgt="254 252 248 240 224 192 128"
     set -- ${maskpat:0:$(( ($1 / 8) * 4 ))}${maskdgt:$(( (7 - ($1 % 8)) * 4 )):3}
     echo ${1-0}.${2-0}.${3-0}.${4-0}
 }
 
 # Gracefully cp only if source file/dir exists
 # cp_it source destination
 function cp_it {
     if [ -e $1 ] || [ -d $1 ]; then
         cp -pRL $1 $2
     fi
 }
 
 # HTTP and HTTPS proxy servers are supported via the usual environment variables [1]
 # ``http_proxy``, ``https_proxy`` and ``no_proxy``. They can be set in
 # ``localrc`` or on the command line if necessary::
 #
 # [1] http://www.w3.org/Daemon/User/Proxies/ProxyClients.html
 #
 #     http_proxy=http://proxy.example.com:3128/ no_proxy=repo.example.net ./stack.sh
 

 function export_proxy_variables {

     if isset http_proxy ; then

         export http_proxy=$http_proxy
     fi

     if isset https_proxy ; then

         export https_proxy=$https_proxy
     fi

     if isset no_proxy ; then

         export no_proxy=$no_proxy
     fi
 }
 
 # Returns true if the directory is on a filesystem mounted via NFS.

 function is_nfs_directory {

     local mount_type=`stat -f -L -c %T $1`
     test "$mount_type" == "nfs"
 }
 
 # Return the network portion of the given IP address using netmask
 # netmask is in the traditional dotted-quad format
 # maskip ip-address netmask

 function maskip {

     local ip=$1
     local mask=$2
     local l="${ip%.*}"; local r="${ip#*.}"; local n="${mask%.*}"; local m="${mask#*.}"
     local subnet=$((${ip%%.*}&${mask%%.*})).$((${r%%.*}&${m%%.*})).$((${l##*.}&${n##*.})).$((${ip##*.}&${mask##*.}))
     echo $subnet
 }
 
 # Service wrapper to restart services
 # restart_service service-name

 function restart_service {

     if is_ubuntu; then
         sudo /usr/sbin/service $1 restart
     else
         sudo /sbin/service $1 restart
     fi
 }
 
 # Only change permissions of a file or directory if it is not on an
 # NFS filesystem.

 function safe_chmod {

     _safe_permission_operation chmod $@
 }
 
 # Only change ownership of a file or directory if it is not on an NFS
 # filesystem.

 function safe_chown {

     _safe_permission_operation chown $@
 }
 
 # Service wrapper to start services
 # start_service service-name

 function start_service {

     if is_ubuntu; then
         sudo /usr/sbin/service $1 start
     else
         sudo /sbin/service $1 start
     fi
 }
 
 # Service wrapper to stop services
 # stop_service service-name

 function stop_service {

     if is_ubuntu; then
         sudo /usr/sbin/service $1 stop
     else
         sudo /sbin/service $1 stop
     fi
 }
 
 
 # Restore xtrace
 $XTRACE
 
 # Local variables:
 # mode: shell-script
 # End: