common/renameat2

##/bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2014 Miklos Szeredi.  All Rights Reserved.
#
# renameat2 helpers

# Setup source or dest
#
_setup_one()
{
	local path=$1
	local type=$2

	case $type in
		none)	;;
		regu)	echo foo > $path;;
		symb)	ln -s foo $path;;
		dire)	mkdir $path;;
		tree)	mkdir $path; echo foo > $path/bar;;
	esac
}

#
# Cleanup source or dest
#
_cleanup_one()
{
	local path=$1

	if test -d $path; then
		rm -f $path/bar
		rmdir $path
	else
		rm -f $path
	fi
}

#
# Check type of source or destination
#
_showtype_one()
{
	local path=$1

	if test -e $path -o -h $path; then
		if test -d $path -a -e $path/bar; then
			echo -n "tree"
		else
			echo -n `stat -c %F $path | cut -b-4`
		fi
	else
		echo -n "none"
	fi
}

#
# This runs renameat2 on all combinations of source and dest
#
_rename_tests_source_dest()
{
	local source=$1
	local dest=$2
	local options=$3
	local flags=$4

	for stype in none regu symb dire tree; do
		for dtype in none regu symb dire tree; do
			echo -n "$options $stype/$dtype -> "
			_setup_one $source $stype
			_setup_one $dest $dtype
			$here/src/renameat2 $source $dest $flags
			if test $? == 0; then
				_showtype_one $source
				echo -n "/"
				_showtype_one $dest
				echo "."
			fi
			_cleanup_one $source
			_cleanup_one $dest
		done
	done
}

#
# This runs _rename_tests_source_dest() for both same-directory and
# cross-directory renames
#
_rename_tests()
{
	local testdir=$1
	local flags=$2

	#same directory renames
	_rename_tests_source_dest $testdir/src $testdir/dst     "samedir " $flags

	#cross directory renames
	mkdir $testdir/x $testdir/y
	_rename_tests_source_dest $testdir/x/src $testdir/y/dst "crossdir" $flags
	rmdir $testdir/x $testdir/y
}

#
# This checks whether the renameat2 syscall is supported
#
_require_renameat2()
{
	local flags=$1
	local rename_dir=`mktemp -d -p $TEST_DIR`
	local cmd=""

	if test ! -x $here/src/renameat2; then
		_notrun "renameat2 binary not found"
	fi

	touch $rename_dir/foo
	case $flags in
	"noreplace")
		cmd="-n $rename_dir/foo $rename_dir/bar"
		;;
	"exchange")
		touch $rename_dir/bar
		cmd="-x $rename_dir/foo $rename_dir/bar"
		;;
	"whiteout")
		touch $rename_dir/bar
		cmd="-w $rename_dir/foo $rename_dir/bar"
		;;
	"")
		cmd=""
		;;
	*)
		rm -rf $rename_dir
		_fail "_require_renameat2: only support noreplace,exchange,whiteout rename flags"
		;;
	esac
	if ! $here/src/renameat2 -t $cmd; then
		rm -rf $rename_dir
		_notrun "kernel doesn't support renameat2 syscall"
	fi
	rm -rf $rename_dir
}