1 files changed, 169 insertions, 0 deletions
diff --git a/share/spack/docker/handle-prompt.sh b/share/spack/docker/handle-prompt.sh
new file mode 100644
index 0000000000..d523ac3a31
--- /dev/null
+++ b/share/spack/docker/handle-prompt.sh
@@ -0,0 +1,169 @@
+# Copyright 2013-2018 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+if [ x$SPACK_PROMPT '!=' x0 ] ; then
+
+__tmp="`mktemp -d`"
+
+__trylock() {
+    local dir
+    dir="$__tmp/$1.lock"
+    mkdir "$dir" &>/dev/null
+    return $?
+}
+
+__queue_init() {
+    local r
+    local w
+
+    mkdir "$__tmp/$1.read.lock" ; r=$?
+    mkdir "$__tmp/$1.write.lock" ; w=$?
+
+    if [ "$r" '=' '0' -a "$w" '=' '0' ] ; then
+        return 0
+    else
+        return 1
+    fi
+}
+
+__queue_try_read() {
+    __trylock "$1.read"
+    return $?
+}
+
+__queue_try_write() {
+    __trylock "$1.write"
+    return $?
+}
+
+__queue_make_readable() {
+    rm -r "$__tmp/$1.read.lock" &>/dev/null
+    return $?
+}
+
+__queue_make_writable() {
+    rm -r "$__tmp/$1.write.lock" &>/dev/null
+    return $?
+}
+
+__read() {
+    cat "$__tmp/$1" 2> /dev/null
+    return $?
+}
+
+__write() {
+    cat > "$__tmp/$1" 2> /dev/null
+    return $?
+}
+
+__revparse_head() {
+    head="`git -C /spack rev-parse $@ HEAD 2>/dev/null`"
+    result="$?"
+    if [ "$result" '!=' '0' ] ; then
+        head="`git --git-dir=/spack/.git \\
+              --work-tree=/spack rev-parse $@ HEAD 2>/dev/null`"
+        result="$?"
+    fi
+
+    echo "$head"
+    return $result
+}
+
+__git_head() {
+    head="`__revparse_head --abbrev-ref`"
+    if [ "$?" '=' '0' ] ; then
+        if [ "$head" '=' 'HEAD' ] ; then
+            head="`__revparse_head | cut -c1-8`..."
+        fi
+
+        echo "$head"
+    fi
+}
+
+__update_prompt() {
+    local prompt
+    prompt=''
+    linux_distro="$DOCKERFILE_DISTRO"
+    if [ -n "$linux_distro" ] ; then
+        linux_distro='\[\e[1;34m\][\[\e[0;34m\]'"$linux_distro"'\[\e[1;34m\]]'
+        if [ -n "$prompt" ] ; then
+            prompt="$prompt "
+        fi
+        prompt="$prompt$linux_distro"
+    fi
+
+    git_head="`__git_head`"
+
+    if [ -n "$git_head" ] ; then
+        git_head='\[\e[1;32m\](\[\e[0;32m\]'"$git_head"'\[\e[1;32m\])'
+        if [ -n "$prompt" ] ; then
+            prompt="$prompt "
+        fi
+        prompt="$prompt$git_head"
+    fi
+
+    if [ -n "$prompt" ] ; then
+        prompt="$prompt "
+    fi
+    prompt="$prompt"'\[\e[0;m\]\W: '
+    echo "$prompt" | __write prompt
+}
+
+set -m
+(
+    __queue_init query
+    __queue_init prompt
+
+    __update_prompt
+    __queue_make_readable prompt
+
+    __queue_make_writable query
+
+    while sleep 0.010 ; do
+        last_q_time=''
+
+        while sleep 0.010 ; do
+            q_time="`date +%s%N`"
+            if __queue_try_read query ; then
+                last_q_time="$q_time"
+                __queue_make_writable query
+            fi
+
+            if [ -n "$last_q_time" -a \
+                "$(( (q_time - last_q_time)/10000000 > 100 ))" '=' '1' ] ; then
+                break
+            fi
+        done
+
+        __update_prompt
+        __queue_make_readable prompt
+    done
+) &>/dev/null &
+set +m
+
+__update_prompt_main_first_call=1
+__update_prompt_main() {
+    if [ "$__update_prompt_main_first_call" '=' '1' ] ; then
+        while sleep 0.001 ; do
+            if __queue_try_read prompt ; then
+                PS1="`__read prompt`"
+                break
+            fi
+        done
+        __update_prompt_main_first_call=0
+    else
+        if __queue_try_read prompt ; then
+            PS1="`__read prompt`"
+        fi
+    fi
+
+    if __queue_try_write query ; then
+        __queue_make_readable query
+    fi
+}
+
+PROMPT_COMMAND=__update_prompt_main
+
+fi # [ x$SPACK_PROMPT '!=' x0 ]