#!/usr/bin/env python

##
# Copyright (c) 2007 Apple Inc.
#
# This is the MIT license.  This software may also be distributed under the
# same terms as Python (the PSF license).
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
# IN THE SOFTWARE.
##

import sys
import os
import getopt
import xattr

def usage(e=None):
    if e:
        print e
        print ""

    name = os.path.basename(sys.argv[0])
    print "usage: %s [-l] file [file ...]" % (name,)
    print "       %s -p [-l] attr_name file [file ...]" % (name,)
    print "       %s -w attr_name attr_value file [file ...]" % (name,)
    print "       %s -d attr_name file [file ...]" % (name,)
    print ""
    print "The first form lists the names of all xattrs on the given file(s)."
    print "The second form (-p) prints the value of the xattr attr_name."
    print "The third form (-w) sets the value of the xattr attr_name to attr_value."
    print "The fourth form (-d) deletes the xattr attr_name."
    print ""
    print "options:"
    print "  -h: print this help"
    print "  -l: print long format (attr_name: attr_value)"

    if e:
        sys.exit(64)
    else:
        sys.exit(0)

def main():
    try:
        (optargs, args) = getopt.getopt(sys.argv[1:], "hlpwd", ["help"])
    except getopt.GetoptError, e:
        usage(e)

    attr_name   = None
    long_format = False
    read        = False
    write       = False
    delete      = False
    status      = 0

    for opt, arg in optargs:
        if opt in ("-h", "--help"):
            usage()
        elif opt == "-l":
            long_format = True
        elif opt == "-p":
	    read = True
        elif opt == "-w":
	    write = True
        elif opt == "-d":
	    delete = True

    if write or delete:
	if long_format:
	    usage("-l not allowed with -w or -p")

    if read or write or delete:
	if not args:
	    usage("No attr_name")
	attr_name = args.pop(0)

    if write:
	if not args:
	    usage("No attr_value")
	attr_value = args.pop(0)

    if len(args) > 1:
	multiple_files = True
    else:
	multiple_files = False

    for filename in args:
	def onError(e):
	    if not os.path.exists(filename):
		sys.stderr.write("No such file: %s\n" % (filename,))
	    else:
		sys.stderr.write(str(e) + "\n")
	    status = 1

	try:
	    attrs = xattr.xattr(filename)
	except (IOError, OSError), e:
	    onError(e)
	    continue

	if write:
	    try:
		attrs[attr_name] = attr_value
	    except (IOError, OSError), e:
		onError(e)
		continue

	elif delete:
	    try:
		del attrs[attr_name]
	    except (IOError, OSError), e:
		onError(e)
		continue
	    except KeyError:
		onError("No such xattr: %s" % (attr_name,))
		continue

	else:
	    try:
		if read:
		    attr_names = (attr_name,)
		else:
		    attr_names = attrs.keys()
	    except (IOError, OSError), e:
		onError(e)
		continue

	    if multiple_files:
		file_prefix = "%s: " % (filename,)
	    else:
		file_prefix = ""

	    for attr_name in attr_names:
		try:
		    if long_format:
			print "".join((file_prefix, "%s: " % (attr_name,), attrs[attr_name]))
		    else:
			if read:
			    print "".join((file_prefix, attrs[attr_name]))
			else:
			    print "".join((file_prefix, attr_name))
		except KeyError:
		    onError("%sNo such xattr: %s" % (file_prefix, attr_name))
		    continue

    sys.exit(status)

if __name__ == "__main__":
    main()