#! /bin/sh

# Root of targets tools + dest directories
# or unset to default to a native build.

# This script assumes target tools in $root/tools 
# and target's destdir in $root/dest, the result of a NetBSD build.sh.
# ...or the native root, when we don't cross-compile
root=${CROSS_ROOT:-/}

incadd=""
native=false
if [ $root = "/" ]; then
	native=true
else
	# What's the tools/bin prefix (if we're cross-building)?
	gnuarch=${GNU_CROSS_TARGET:?}

	# A special hack for netbsd-8 targets.
	# netbsd-8 has gcc 5.5, but llvm and rust needs >= 7
	# so we build tools from -9, and try to use that, but
	# then the include path becomes wrong, and <stdatomic.h>
	# is no longer picked up automatically by the compiler
	# from the target destination directory
	case $gnuarch in
		sparc64*)	incadd="-I=/usr/include/gcc-5"
				;;

				# immintrin & from gcc-5 not
				# compatible with gcc7, apparently
		i[3456]86*)	incadd="-I=/usr/include/gcc-7"
				;;

				# mips64 does soft-float
		mips64*)	madd="-msoft-float"
				;;
	esac
	# We build both for -8 and -9 due to ABI differences,
	# so can't just test $gnuarch...  Yes, a vile hack.
	if [ "$root" = "/u/macppc" ]; then
		incadd="-I=/usr/include/gcc-5"
	fi
fi

# Who are we a wrapper for? (Typically either gcc or c++)
who=$(basename $0 | sed -e 's/-wrap$//')

args=""
if [ ! -z "$madd" ]; then
	args="$args $madd"
fi

# May need to add $linkadd before first -l or fist -L
linkadd="-Wl,--sysroot=${root}/dest"
# (perhaps this is overly cautious, other adjustments we do
# below may be sufficient...)
# Lib directories to ensure we search and have in run-path
libs="/lib /usr/lib /usr/pkg/lib"

for d in $libs; do
	if ! $native; then
		linkadd="$linkadd -L=$d"
		linkadd="$linkadd -Wl,-rpath-link=${root}/dest/$d"
	fi
	# Run-path is for when we execute on the target,
	# so no $root prefix
	linkadd="$linkadd -Wl,-rpath,$d"
done

# ...and add a placeholder so we can tweak RPATH with chrpath,
# since chrpath can't extend the length of the run path
# (This may also not be needed, we use LD_LIBRARY_PATH instead)
placeholder="placeholder-$(date | openssl dgst -sha1 | \
	awk '{ print $2 }')"
linkadd="$linkadd -Wl,-rpath,/$placeholder"
# the / is a sneaky attempt to let it past cwrapper...

# More debugging
linkadd="$linkadd -Wl,--verbose"

linktweaked=false

# Step through args, tweak where required
set -- "$@"
while [ $# -gt 0 ]; do
	case "$1" in
# Insert = at the front of -isystem args.
# This is to get --sysroot prepended, so that
# we pick up the correct set of header files.
# (I thought this wasn't reqired, but apparently it is...)
		-isystem)
			shift
			args="$args -isystem =$1"
			;;
# Also doctor -I directives of known paths and
# redirect them to the --sysroot.
		-I/usr/include)
			args="$args -I=/usr/include"
			;;
		-I/usr/include/krb5)
			args="$args -I=/usr/include/krb5"
			;;
		-I/usr/pkg/include)
# Try to drop this...
			if ! $native; then
				args="$args -I=/usr/pkg/include"
			fi
			;;
		-I)
			if [ $2 = "/usr/include" ]; then
				args="$args -I=/usr/include"
				shift
			elif [ $2 = "/usr/include/krb5" ]; then
				args="$args -I=/usr/include/krb5"
				shift
			elif [ $2 = "/usr/pkg/include" ]; then
# Try to drop this too...
				if ! $native; then
					args="$args -I=/usr/pkg/include"
				fi
				shift
			else
				args="$args -I"
			fi
			;;
		-l*)
			if ! $linktweaked; then
				args="$args $linkadd"
				linktweaked=true
			fi
			args="$args $1"
			;;
		-L)
			if ! $linktweaked; then
				args="$args $linkadd"
				linktweaked=true
			fi
			shift
			tweaked=false
			# redirect these to -Wl,--sysroot
			for d in /lib /usr/lib /usr/pkg/lib; do
				if [ $1 = $d ]; then
					args="$args -L =$d"
					tweaked=true
				fi
			done
			# Not redirected?  If so we need to add
			if ! $tweaked; then
				args="$args -L $1"
			fi
			;;
			
		-L/lib)
			if ! $linktweaked; then
				args="$args $linkadd"
				linktweaked=true
			fi
			args="$args -L=/lib"
			;;
		-L/usr/lib)
			if ! $linktweaked; then
				args="$args $linkadd"
				linktweaked=true
			fi
			args="$args -L=/usr/lib"
			;;
		-L/usr/pkg/lib)
			if ! $linktweaked; then
				args="$args $linkadd"
				linktweaked=true
			fi
			args="$args -L=/usr/pkg/lib"
			;;
		-Wl,--enable-new-dtags)
			# ignore
			;;
		*)
			args="$args $1"
			;;
	esac
	shift
done

if $native; then
	# Try to avoid cwrappers, which does "undocumented magic"
	# by invoking the compiler "directly".
	#cmd="/usr/bin/${who} $args"
	# (however, this wrapper isn't used when buliding natively...)
	cmd="${who} $args"
else
	cmd="${root}/tools/bin/${gnuarch}-${who} \
		--sysroot=${root}/dest \
		$incadd \
		$args"
fi

# Cannot echo to stdout, messes up e.g. "gcc -print-prog-name=ld" output...
#echo $cmd >> /tmp/gcc-wrap.log
exec $cmd