#!/bin/sh
# Runs a shell command (or interactive shell) using the binaries and
# libraries bundled with this app.

set -e

base="$(dirname "$0")"

if [ ! -d "$base" ]; then
	echo "** cannot find base directory (I seem to be $0)" >&2
	exit 1
fi

if [ ! -e "$base/bin/debug-me" ]; then
	echo "** base directory $base does not contain bin/debug-me" >&2
	exit 1
fi

# Get absolute path to base, to avoid breakage when things change directories.
orig="$(pwd)"
cd "$base"
base="$(pwd)"
cd "$orig"

# --library-path won't work if $base contains : or ;
# Detect this problem, and work around it by using a temp directory.
if echo "$base" | grep -q '[:;]'; then
	tbase=$(mktemp -d -p /tmp debugmeshimXXXXXXXXX 2>/dev/null || true)
	if [ -z "$tbase" ]; then
		tbase="/tmp/debugmeshim.$$"
		mkdir "$tbase"
	fi
	ln -s "$base" "$tbase/link"
	base="$tbase/link"
	cleanuptbase () {
		rm -rf "$tbase"
	}
	trap cleanuptbase EXIT
fi

# Put our binaries first, to avoid issues with out of date or incompatible
# system binaries. Extra binaries come after system path.
ORIG_PATH="$PATH"
export ORIG_PATH
PATH="$base/bin:$PATH:$base/extra"
export PATH

# These env vars are used by the shim wrapper around each binary.
for lib in $(cat "$base/libdirs"); do
	DEBUG_ME_LD_LIBRARY_PATH="$base/$lib:$DEBUG_ME_LD_LIBRARY_PATH"
done
export DEBUG_ME_LD_LIBRARY_PATH
DEBUG_ME_DIR="$base"
export DEBUG_ME_DIR

ORIG_GCONV_PATH="$GCONV_PATH"
export ORIG_GCONV_PATH
GCONV_PATH="$base/$(cat "$base/gconvdir")"
export GCONV_PATH

ORIG_MANPATH="$MANPATH"
export ORIG_MANPATH
MANPATH="$base/usr/share/man:$MANPATH"
export MANPATH

DEBUG_ME_EXE="$base/debug-me"
export DEBUG_ME_EXE

if [ "$1" ]; then
	cmd="$1"
	shift 1
	if [ -z "$tbase" ]; then
		exec "$cmd" "$@"
	else
		# allow EXIT trap to cleanup
		"$cmd" "$@"
	fi
else
	sh
fi