diff --git a/functions b/functions
new file mode 100644
index 0000000000..01c4758fa0
--- /dev/null
+++ b/functions
@@ -0,0 +1,91 @@
+# functions - Common functions used by DevStack components
+
+
+# apt-get wrapper to set arguments correctly
+# apt_get package [package ...]
+function apt_get() {
+    [[ "$OFFLINE" = "True" ]] && return
+    local sudo="sudo"
+    [[ "$(id -u)" = "0" ]] && sudo="env"
+    $sudo DEBIAN_FRONTEND=noninteractive \
+        http_proxy=$http_proxy https_proxy=$https_proxy \
+        apt-get --option "Dpkg::Options::=--force-confold" --assume-yes "$@"
+}
+
+
+# Gracefully cp only if source file/dir exists
+# cp_it source destination
+function cp_it {
+    if [ -e $1 ] || [ -d $1 ]; then
+        cp -pRL $1 $2
+    fi
+}
+
+
+# git clone only if directory doesn't exist already.  Since ``DEST`` might not
+# be owned by the installation user, we create the directory and change the
+# ownership to the proper user.
+# Set global RECLONE=yes to simulate a clone when dest-dir exists
+# git_clone remote dest-dir branch
+function git_clone {
+    [[ "$OFFLINE" = "True" ]] && return
+
+    GIT_REMOTE=$1
+    GIT_DEST=$2
+    GIT_BRANCH=$3
+
+    if echo $GIT_BRANCH | egrep -q "^refs"; then
+        # If our branch name is a gerrit style refs/changes/...
+        if [[ ! -d $GIT_DEST ]]; then
+            git clone $GIT_REMOTE $GIT_DEST
+        fi
+        cd $GIT_DEST
+        git fetch $GIT_REMOTE $GIT_BRANCH && git checkout FETCH_HEAD
+    else
+        # do a full clone only if the directory doesn't exist
+        if [[ ! -d $GIT_DEST ]]; then
+            git clone $GIT_REMOTE $GIT_DEST
+            cd $GIT_DEST
+            # This checkout syntax works for both branches and tags
+            git checkout $GIT_BRANCH
+        elif [[ "$RECLONE" == "yes" ]]; 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 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 $GIT_DEST -name '*.pyc' -delete
+            git checkout -f origin/$GIT_BRANCH
+            # a local branch might not exist
+            git branch -D $GIT_BRANCH || true
+            git checkout -b $GIT_BRANCH
+        fi
+    fi
+}
+
+
+# pip install wrapper to set cache and proxy environment variables
+# pip_install package [package ...]
+function pip_install {
+    [[ "$OFFLINE" = "True" ]] && return
+    sudo PIP_DOWNLOAD_CACHE=/var/cache/pip \
+        HTTP_PROXY=$http_proxy \
+        HTTPS_PROXY=$https_proxy \
+        pip install --use-mirrors $@
+}
+
+
+# Normalize config values to True or False
+# VAR=`trueorfalse default-value test-value`
+function trueorfalse() {
+    local default=$1
+    local testval=$2
+
+    [[ -z "$testval" ]] && { echo "$default"; return; }
+    [[ "0 no false False FALSE" =~ "$testval" ]] && { echo "False"; return; }
+    [[ "1 yes true True TRUE" =~ "$testval" ]] && { echo "True"; return; }
+    echo "$default"
+}
diff --git a/stack.sh b/stack.sh
index 8dc54ce248..c40b24c996 100755
--- a/stack.sh
+++ b/stack.sh
@@ -35,6 +35,9 @@ fi
 # Keep track of the current devstack directory.
 TOP_DIR=$(cd $(dirname "$0") && pwd)
 
+# Import common functions
+. $TOP_DIR/functions
+
 # stack.sh keeps the list of **apt** and **pip** dependencies in external
 # files, along with config templates and other useful files.  You can find these
 # in the ``files`` directory (next to this script).  We will reference this
@@ -86,16 +89,6 @@ source ./stackrc
 # Destination path for installation ``DEST``
 DEST=${DEST:-/opt/stack}
 
-# apt-get wrapper to just get arguments set correctly
-function apt_get() {
-    [[ "$OFFLINE" = "True" ]] && return
-    local sudo="sudo"
-    [ "$(id -u)" = "0" ] && sudo="env"
-    $sudo DEBIAN_FRONTEND=noninteractive \
-        http_proxy=$http_proxy https_proxy=$https_proxy \
-        apt-get --option "Dpkg::Options::=--force-confold" --assume-yes "$@"
-}
-
 # Check to see if we are already running a stack.sh
 if screen -ls | egrep -q "[0-9].stack"; then
     echo "You are already running a stack.sh session."
@@ -155,18 +148,6 @@ else
     sudo mv $TEMPFILE /etc/sudoers.d/stack_sh_nova
 fi
 
-# Normalize config values to True or False
-# VAR=`trueorfalse default-value test-value`
-function trueorfalse() {
-    local default=$1
-    local testval=$2
-
-    [[ -z "$testval" ]] && { echo "$default"; return; }
-    [[ "0 no false False FALSE" =~ "$testval" ]] && { echo "False"; return; }
-    [[ "1 yes true True TRUE" =~ "$testval" ]] && { echo "True"; return; }
-    echo "$default"
-}
-
 # Set True to configure stack.sh to run cleanly without Internet access.
 # stack.sh must have been previously run with Internet access to install
 # prerequisites and initialize $DEST.
@@ -542,14 +523,6 @@ function get_packages() {
     done
 }
 
-function pip_install {
-    [[ "$OFFLINE" = "True" ]] && return
-    sudo PIP_DOWNLOAD_CACHE=/var/cache/pip \
-        HTTP_PROXY=$http_proxy \
-        HTTPS_PROXY=$https_proxy \
-        pip install --use-mirrors $@
-}
-
 # install apt requirements
 apt_get update
 apt_get install $(get_packages)
@@ -557,48 +530,6 @@ apt_get install $(get_packages)
 # install python requirements
 pip_install `cat $FILES/pips/* | uniq`
 
-# 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.
-function git_clone {
-    [[ "$OFFLINE" = "True" ]] && return
-
-    GIT_REMOTE=$1
-    GIT_DEST=$2
-    GIT_BRANCH=$3
-
-    if echo $GIT_BRANCH | egrep -q "^refs"; then
-        # If our branch name is a gerrit style refs/changes/...
-        if [ ! -d $GIT_DEST ]; then
-            git clone $GIT_REMOTE $GIT_DEST
-        fi
-        cd $GIT_DEST
-        git fetch $GIT_REMOTE $GIT_BRANCH && git checkout FETCH_HEAD
-    else
-        # do a full clone only if the directory doesn't exist
-        if [ ! -d $GIT_DEST ]; then
-            git clone $GIT_REMOTE $GIT_DEST
-            cd $GIT_DEST
-            # This checkout syntax works for both branches and tags
-            git checkout $GIT_BRANCH
-        elif [[ "$RECLONE" == "yes" ]]; 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 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 $GIT_DEST -name '*.pyc' -delete
-            git checkout -f origin/$GIT_BRANCH
-            # a local branch might not exist
-            git branch -D $GIT_BRANCH || true
-            git checkout -b $GIT_BRANCH
-        fi
-    fi
-}
-
 # compute service
 git_clone $NOVA_REPO $NOVA_DIR $NOVA_BRANCH
 # python client library to nova that horizon (and others) use
diff --git a/tools/build_ramdisk.sh b/tools/build_ramdisk.sh
index feaa8a97ad..7c1600b1ec 100755
--- a/tools/build_ramdisk.sh
+++ b/tools/build_ramdisk.sh
@@ -47,7 +47,10 @@ IMG_FILE=$1
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 # Store cwd
 CWD=`pwd`
@@ -170,35 +173,6 @@ if [ ! -r "`ls $MNTDIR/boot/vmlinuz-*-generic | head -1`" ]; then
     chroot $MNTDIR apt-get install -y linux-generic
 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.
-function git_clone {
-
-    # clone new copy or fetch latest changes
-    CHECKOUT=${MNTDIR}$2
-    if [ ! -d $CHECKOUT ]; then
-        mkdir -p $CHECKOUT
-        git clone $1 $CHECKOUT
-    else
-        pushd $CHECKOUT
-        git fetch
-        popd
-    fi
-
-    # FIXME(ja): checkout specified version (should works for branches and tags)
-
-    pushd $CHECKOUT
-    # checkout the proper branch/tag
-    git checkout $3
-    # force our local version to be the same as the remote version
-    git reset --hard origin/$3
-    popd
-
-    # give ownership to the stack user
-    chroot $MNTDIR chown -R stack $2
-}
-
 git_clone $NOVA_REPO $DEST/nova $NOVA_BRANCH
 git_clone $GLANCE_REPO $DEST/glance $GLANCE_BRANCH
 git_clone $KEYSTONE_REPO $DEST/keystone $KEYSTONE_BRANCH
diff --git a/tools/build_tempest.sh b/tools/build_tempest.sh
index aa44766ae8..230e8f9b72 100755
--- a/tools/build_tempest.sh
+++ b/tools/build_tempest.sh
@@ -26,7 +26,10 @@ trap cleanup SIGHUP SIGINT SIGTERM SIGQUIT EXIT
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 # Abort if localrc is not set
 if [ ! -e $TOP_DIR/localrc ]; then
@@ -43,42 +46,8 @@ DEST=${DEST:-/opt/stack}
 
 TEMPEST_DIR=$DEST/tempest
 
-DIST_NAME=${DIST_NAME:-oneiric}
-
-# 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.
-function git_clone {
-
-    GIT_REMOTE=$1
-    GIT_DEST=$2
-    GIT_BRANCH=$3
-
-    # do a full clone only if the directory doesn't exist
-    if [ ! -d $GIT_DEST ]; then
-        git clone $GIT_REMOTE $GIT_DEST
-        cd $2
-        # This checkout syntax works for both branches and tags
-        git checkout $GIT_BRANCH
-    elif [[ "$RECLONE" == "yes" ]]; 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 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 $GIT_DEST -name '*.pyc' -delete
-        git checkout -f origin/$GIT_BRANCH
-        # a local branch might not exist
-        git branch -D $GIT_BRANCH || true
-        git checkout -b $GIT_BRANCH
-    fi
-}
-
 # Install tests and prerequisites
-sudo PIP_DOWNLOAD_CACHE=/var/cache/pip pip install --use-mirrors `cat $TOP_DIR/files/pips/tempest`
+pip_install `cat $TOP_DIR/files/pips/tempest`
 
 git_clone $TEMPEST_REPO $TEMPEST_DIR $TEMPEST_BRANCH
 
diff --git a/tools/build_uec.sh b/tools/build_uec.sh
index 04e1a45913..ed5a017174 100755
--- a/tools/build_uec.sh
+++ b/tools/build_uec.sh
@@ -8,7 +8,10 @@ fi
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 cd $TOP_DIR
 
@@ -34,7 +37,7 @@ fi
 
 # Install deps if needed
 DEPS="kvm libvirt-bin kpartx cloud-utils curl"
-apt-get install -y --force-yes $DEPS || true # allow this to fail gracefully for concurrent builds
+apt_get install -y --force-yes $DEPS || true # allow this to fail gracefully for concurrent builds
 
 # Where to store files and instances
 WORK_DIR=${WORK_DIR:-/opt/uecstack}
diff --git a/tools/build_uec_ramdisk.sh b/tools/build_uec_ramdisk.sh
index 174eaac72c..32f90c05c0 100755
--- a/tools/build_uec_ramdisk.sh
+++ b/tools/build_uec_ramdisk.sh
@@ -40,7 +40,10 @@ DEST_FILE=$1
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 cd $TOP_DIR
 
@@ -68,7 +71,7 @@ fi
 
 # Install deps if needed
 DEPS="kvm libvirt-bin kpartx cloud-utils curl"
-apt-get install -y --force-yes $DEPS
+apt_get install -y --force-yes $DEPS
 
 # Where to store files and instances
 CACHEDIR=${CACHEDIR:-/opt/stack/cache}
@@ -113,35 +116,6 @@ if [ ! -r "`ls $MNT_DIR/boot/vmlinuz-*-generic | head -1`" ]; then
     chroot $MNT_DIR apt-get install -y linux-generic
 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.
-function git_clone {
-
-    # clone new copy or fetch latest changes
-    CHECKOUT=${MNT_DIR}$2
-    if [ ! -d $CHECKOUT ]; then
-        mkdir -p $CHECKOUT
-        git clone $1 $CHECKOUT
-    else
-        pushd $CHECKOUT
-        git fetch
-        popd
-    fi
-
-    # FIXME(ja): checkout specified version (should works for branches and tags)
-
-    pushd $CHECKOUT
-    # checkout the proper branch/tag
-    git checkout $3
-    # force our local version to be the same as the remote version
-    git reset --hard origin/$3
-    popd
-
-    # give ownership to the stack user
-    chroot $MNT_DIR chown -R stack $2
-}
-
 git_clone $NOVA_REPO $DEST/nova $NOVA_BRANCH
 git_clone $GLANCE_REPO $DEST/glance $GLANCE_BRANCH
 git_clone $KEYSTONE_REPO $DEST/keystone $KEYSTONE_BRANCH
diff --git a/tools/configure_tempest.sh b/tools/configure_tempest.sh
index 00add9a336..f6ef0d3b95 100755
--- a/tools/configure_tempest.sh
+++ b/tools/configure_tempest.sh
@@ -30,7 +30,10 @@ trap cleanup SIGHUP SIGINT SIGTERM SIGQUIT EXIT
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 # Abort if localrc is not set
 if [ ! -e $TOP_DIR/localrc ]; then
diff --git a/tools/copy_dev_environment_to_uec.sh b/tools/copy_dev_environment_to_uec.sh
index c949b329df..d5687dc14d 100755
--- a/tools/copy_dev_environment_to_uec.sh
+++ b/tools/copy_dev_environment_to_uec.sh
@@ -8,7 +8,10 @@ set -o errexit
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 # Change dir to top of devstack
 cd $TOP_DIR
@@ -47,13 +50,6 @@ echo stack:pass | chroot $STAGING_DIR chpasswd
 ( umask 226 && echo "stack ALL=(ALL) NOPASSWD:ALL" \
     > $STAGING_DIR/etc/sudoers.d/50_stack_sh )
 
-# Gracefully cp only if source file/dir exists
-function cp_it {
-    if [ -e $1 ] || [ -d $1 ]; then
-        cp -pRL $1 $2
-    fi
-}
-
 # Copy over your ssh keys and env if desired
 cp_it ~/.ssh $STAGING_DIR/$DEST/.ssh
 cp_it ~/.ssh/id_rsa.pub $STAGING_DIR/$DEST/.ssh/authorized_keys
diff --git a/tools/get_uec_image.sh b/tools/get_uec_image.sh
index f66f2bc2fb..09630740dc 100755
--- a/tools/get_uec_image.sh
+++ b/tools/get_uec_image.sh
@@ -6,7 +6,10 @@ ROOTSIZE=${ROOTSIZE:-2000}
 
 # Keep track of the current directory
 TOOLS_DIR=$(cd $(dirname "$0") && pwd)
-TOP_DIR=`cd $TOOLS_DIR/..; pwd`
+TOP_DIR=$(cd $TOOLS_DIR/..; pwd)
+
+# Import common functions
+. $TOP_DIR/functions
 
 # exit on error to stop unexpected errors
 set -o errexit