shell-source

#!/bin/sh -efu
### This file is covered by the GNU General Public License,
### which should be included with libshell as the file LICENSE.
### All copyright information are listed in the COPYING.

if [ -z "${__included_shell_source-}" ]; then
__included_shell_source=1

__shell_source_find()
{
	local r f IFS=:
	r="$1"; shift
	f="$1"; shift

	if [ -n "${f##*/*}" ]; then
		set -- ${PATH-}
		while [ "$#" -gt 0 ]; do
			if [ -e "$1/$f" ]; then
				f="$1/$f"
				break
			fi
			shift
		done
	fi
	[ -e "$f" ] || return 1
	eval "$r=\"\$f\""
}

### Execute commands from file in the current environment if file exists.
### Usage: source_if_exists /file arg1 arg2
###    or: source_if_exists  file arg1 arg2
source_if_exists()
{
	local v f
	f="$1";	shift
	! __shell_source_find v "$f" || [ ! -f "$v" ] || . "$v"
}

### Execute commands from file in the current environment if file is not empty.
### Usage: source_if_notempty /file arg1 arg2
###    or: source_if_notempty  file arg1 arg2
source_if_notempty()
{
	local v f
	f="$1"; shift
	! __shell_source_find v "$f" || [ ! -s "$v" ] || . "$v"
}

### Execute commands from file in the current environment if file is executable.
### Usage: source_if_executable /file arg1 arg2
###    or: source_if_executable  file arg1 arg2
source_if_executable()
{
	local v f
	f="$1"; shift
	! __shell_source_find v "$f" || [ ! -x "$v" ] || . "$v"
}

fi #__included_shell_source