sk

#!/bin/bash

#
# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
#

installDir=$(dirname "${BASH_SOURCE[0]}")
clangpp=clang++-6.0
preamble="$installDir/../lib/skip/preamble.ll"
standalone="$installDir/../lib/skip/sk_standalone.cpp.o"
prelude="$installDir/../lib/skip/prelude"
thirdPartyLibDir="$installDir/../lib/skip"
linuxGnuLibDir="$installDir/../lib/x86_64-linux-gnu"
skipRuntimeLib="$installDir/../lib/skip/libskip_runtime.a"
skip_server="$installDir/../bin/skip_server"

if [ -z "$1" ]; then
    command="run"
    root="$PWD"
else
    if [ "$1" == "--args" ]; then
	command="run"
	root="$PWD"
	shift
    else
        command="$1"
	shift

	if [ -z "$1" ]; then
	    root="$PWD"
	else
	    if [ "$1" == "--args" ]; then
		root="$PWD"
	    else
		root="$1"
	    fi
	    shift
	fi
    fi
fi

root=`realpath "$root"`

if [ "$1" == "--args" ]; then
    shift
fi

case $command in
    init|start|stop|status|build|check|run|restart)
	;;
    *)
	>&2 echo "Usage:"
	>&2 echo "\$ sk (init|start|stop|status|build|check|run|restart) dirname";
	exit 1
	;;

esac

project="$root/skip.project.json"
skdir_escape_z="${root//z/zZ}"
tmpdir=$(dirname $(mktemp -u))
skdir="$tmpdir/.skserver_${skdir_escape_z//\//z}"
errfile="$skdir/errors"

if ! [ -d "$root" ]; then
    >&2 echo "*********************************************"
    >&2 echo "ERROR: '$root' is not a valid directory name!"
    >&2 echo "*********************************************"
    exit 1
fi

if [ $command == "init" ]; then
    echo "{" > "$project"
    echo "  \"skipVersion\": \"1.0\"," >> "$project"
    echo "  \"programUnits\": {" >> "$project"
    echo "    \"a.out\": {" >> "$project"
    echo "      \"kind\": \"Program\"," >> "$project"
    echo "      \"sources\": [\".\"]," >> "$project"
    echo "      \"references\": [{ \"path\": \"$prelude\" }]" >> "$project"
    echo "    }" >> "$project"
    echo "  }" >> "$project"
    echo "}" >> "$project"

    exit 0
fi

runAfterBuild=""

if [ $command == "run" ]; then

    if [ -f "$skdir/bin.out" ]; then
	if [[ $(find "$root" -name "*.sk" -newer "$skdir/bin.out") ]]; then
	    runAfterBuild=1
	    command="build"
	else
	    exec "$skdir/bin.out" "$@"
	fi
    else
	runAfterBuild=1
	command="build"
    fi
fi

if ! [ -f "$project" ]; then
    >&2 echo "*********************************************"
    >&2 echo "ERROR: $project doesn't exist!"
    >&2 echo "*********************************************"
    >&2 echo "You can create a default project file with:"
    >&2 echo "\$ sk init $root"
    exit 7
fi

stop() {
    kill -9 `cat "$skdir/pids" 2> /dev/null` 2> /dev/null
    rm -Rf "$skdir"
}

if [ $command == "stop" ]; then
    stop
    echo "Server stopped"
    exit 0
fi

start() {
    skip_server_pid=`ps xa | grep skip_server | grep "$root" | awk '{ print $1 }'`
    if [ "$skip_server_pid" ]; then
        >&2 echo "Another server is already running"
        exit 2
    fi

    fifo_command="$skdir/fifo_command"
    fifo_response="$skdir/fifo_response"

    if ! [ -e "$skdir" ] ; then
	mkdir "$skdir"
    fi

    if ! [ -p "$fifo_command" ]; then
	rm -f "$fifo_command"
	mkfifo "$fifo_command"
    fi

    if ! [ -p "$fifo_response" ]; then
	rm -f "$fifo_response"
	mkfifo "$fifo_response"
    fi

    nohup sleep 86400 > "$fifo_command" < "$fifo_response" 2> /dev/null &
    echo $! > "$skdir/pids"

    if ! [ -d "$root" ] ; then
	echo "$root is not a directory"
	exit 1
    fi

    # This is a scheme to create a unique temporary file name derived
    # from the directory named. We first replace the 'z' with "zZ" and
    # then replace the '/' with z. This way, for example, the directory
    # /tmp/myDirwithZinIt becomes ztmpzmyDirwithzZinIt.
    # The idea is to create a valid filename given an absolute path.

    skdir_escape_z="${root//z/zZ}"
    tmpdir=$(dirname $(mktemp -u))
    skdir="$tmpdir/.skserver_${skdir_escape_z//\//z}"

    if ! [ -e "$skdir" ] ; then
	>&2 echo "Missing directory $skdir"
	exit 2
    fi

    # We use 2 fifos to talk to the skip_server.
    fifo_command="$skdir/fifo_command"
    fifo_response="$skdir/fifo_response"

    if ! [ -p "$fifo_command" ]; then
	>&2 echo "Missing: $fifo_command"
	exit 2
    fi

    if ! [ -p "$fifo_response" ]; then
	>&2 echo "Missing: $fifo_response"
	exit 2
    fi

    find "$root" -name "*.sk" > "$skdir/skfiles"

    read < "$fifo_response" &
    readPid=$!

    nohup "$skip_server" "$root" --export-function-as main=skip_main \
	  --output "$skdir/out.ll" < "$fifo_command" > "$fifo_response" \
	  2> "$skdir/server_errors" &
    echo $! >> "$skdir/pids"

    sleep 1

    skip_server_pid=`ps xawww | grep skip_server | grep "$root" | awk '{ print $1 }'`
    if [ -z "$skip_server_pid" ]; then
        >&2 echo "Could not start the server"
        cat "$skdir/server_errors" 1>&2
	kill -9 `cat "$skdir/pids" 2> /dev/null` 2> /dev/null
        exit 9
    fi

    echo "Server started for: $root"
    wait $readPid
    echo "Ready"
}

if [ $command == "start" ]; then
    start
    exit 0
fi

restart() {
    stop
    start
    echo "Server restarted for: $root"
}

# Let's check if the ".sk" files changed, if it's the case,
# restart the server.

if [ -f "$skdir/skfiles" ]; then
    find "$root" -name "*.sk" > "$skdir/skfiles_new"

    diff -q "$skdir/skfiles" "$skdir/skfiles_new" > /dev/null
    if [ $? -ne 0 ]; then
	echo "Detected a file configuration change"
	restart
    fi
fi

if [ $command == "restart" ]; then
    restart
    exit 0
fi

skip_server_pid=`ps xawww | grep skip_server | grep "$root" | awk '{ print $1 }'`
if [ -z "$skip_server_pid" ]; then
    if [ $command == "status" ]; then
	echo "No server running"
	exit 0
    fi
    echo "No server running, starting one now!"
    start
fi

if [ $command == "status" ]; then
    echo "The server is running"
    exit 0
fi

read < "$skdir/fifo_response" &
readPid=$!

echo $command > "$skdir/fifo_command"

wait $readPid

if cat "$errfile" | head -n 1 | grep --quiet "No error"; then
    if [ $command == "check" ]; then
	cat "$errfile";
	exit 0
    fi
else
    cat "$errfile" >&2;
    rm -f "$skdir/bin.out"
    exit 2
fi

if [ $command == "build" ]; then
    rm -f "$skdir/bin.out"

    # If built is called before the initialization of the server is over,
    # we could be in a situation where the .ll file is not yet ready.
    # This can also happen if another process was asking for a "check"
    # and so the server was responding to that other process.
    # These races are rare enough that we are just going to wait for
    # the file to be written.
    while [ ! -f "$skdir/out.ll" ];
    do
	sleep 1
    done;

    # Adding the preamble to the .ll file
    cat "$preamble" "$skdir/out.ll" > "$skdir/preamble_and_out.ll"

    system=$(uname -s)

    if ! [ -f "$root/.ccopts" ]; then
	ccopts=""
    else
	ccopts=`cat "$root/.ccopts"`
    fi

    "$clangpp" -O2 -g -c "$skdir/preamble_and_out.ll" -o "$skdir/preamble_and_out.o"
    if [ "$system" == "Linux" ]; then

      # Linking it all together
      "$clangpp" -s -o "$skdir/bin.out" -g \
             "$skdir/preamble_and_out.o" "$standalone" \
	     -L"$thirdPartyLibDir/" \
	     "$skipRuntimeLib" \
	     -fPIC -DPIC \
	     -lrt \
	     -Wl,--gc-sections \
	     -DUSE_JEMALLOC -msse4.2 -std=c++14 \
	     -O3 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer \
	     -fdata-sections -ffunction-sections \
	     -lglog -lgflags \
	     -licuuc -licui18n -licuio -licutu -licudata -ljemalloc_pic \
	     -lpcre -lboost_system \
	     -lboost_filesystem -lboost_chrono -lboost_date_time \
	     -levent \
	     -lpthread \
	     -lunwind \
	     -lboost_thread \
	     -lboost_context \
	     -lboost_atomic \
	     -ldl \
	     $ccopts
    else
	if [ "$system" == "Darwin" ]; then
          "$clangpp" -o "$skdir/bin.out" -g \
	     "$skdir/preamble_and_out.o" "$standalone" \
	     -L"$thirdPartyLibDir/" \
	     "$skipRuntimeLib" \
	     -fPIC -DPIC -Wl,-rpath,"$linuxGnuLibDir" \
	     -lboost_thread-mt \
	     -lboost_context-mt \
	     -lboost_atomic-mt \
	     -DUSE_JEMALLOC -msse4.2 -std=c++14 \
	     -O3 -fno-omit-frame-pointer -mno-omit-leaf-frame-pointer \
	     -fdata-sections -ffunction-sections \
	     -lglog -lgflags  \
	     -licuuc -licui18n -licuio -licutu -licudata -ljemalloc_pic \
	     -lpcre -lboost_system \
	     -lboost_filesystem -lboost_chrono -lboost_date_time \
	     -levent -ldl \
	     -lpthread \
	     $ccopts
	else
	    2>&1 echo "Unknown system"
	    exit 2
	fi
    fi


    echo "Written: $skdir/bin.out"
fi

if [ $runAfterBuild ]; then
    exec "$skdir/bin.out" "$@"
fi