#!/usr/bin/python3
#
#Copyright (c) 2006, 2007, Olivier Sessink
#All rights reserved.
#
#Redistribution and use in source and binary forms, with or without
#modification, are permitted provided that the following conditions 
#are met:
#  * Redistributions of source code must retain the above copyright 
#    notice, this list of conditions and the following disclaimer.
#  * Redistributions in binary form must reproduce the above 
#    copyright notice, this list of conditions and the following 
#    disclaimer in the documentation and/or other materials provided 
#    with the distribution.
#  * The names of its contributors may not be used to endorse or 
#    promote products derived from this software without specific 
#    prior written permission.
#
#THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
#"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
#LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 
#FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
#COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 
#INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
#BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
#LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
#CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
#LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
#ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
#POSSIBILITY OF SUCH DAMAGE.
#

from __future__ import print_function

import sys
if sys.version_info > (3, 0):						#Python 3
	from configparser import ConfigParser
else:									#Python 2
	from ConfigParser import ConfigParser
import os
import string
from stat import *
import getopt
import stat

INIPREFIX='/etc/jailkit'
LIBDIR='/usr/share/jailkit'
sys.path.append(LIBDIR)
import jk_lib

def comparecontent(fileA, fileB):
	try:
		fA=open(fileA, 'rb')
		fB=open(fileB, 'rb')
		cont = 1
		retval = 1
		while (cont==1 and retval==1):
			bufA = fA.read(4096)
			bufB = fB.read(4096)
			if (bufA != bufB):
				retval = 0
			if (len(bufA)==0):
				cont = 0
		fA.close()
		fB.close()
		return retval
	except IOError:
		return 0

def comparemetadata(fileA, fileB, onlyifAisnewer=1, sbA=None, sbB=None):
	if (sbA==None):
		sbA = os.lstat(fileA)
	if (sbB==None):
		sbB = os.lstat(fileB)
	if (sbA[stat.ST_MTIME] > sbB[stat.ST_MTIME]): 
		if (sbA[stat.ST_SIZE] != sbB[stat.ST_SIZE]):
			return 0
		if (stat.S_ISLNK(sbA[stat.ST_MODE]) != stat.S_ISLNK(sbB[stat.ST_MODE])):
			return 0
		if (stat.S_ISLNK(sbA[stat.ST_MODE])):
			if (os.readlink(fileA) != os.readlink(fileB)):
				return 0
	return 1

def need_update(original, injail, origstatbuf=None):
	try :
		if (comparemetadata(original, injail,sbA=origstatbuf)==1):
			if (comparecontent(original, injail)==1):
				return 0
		return 1
	except OSError as e:
		errno, _ = e.args
		# files that do not have an original file obviously cannot be updated
		# but they need cleaning
		if (errno == 2):
			return 2
		return 0

def find2update(jail, dir, skips, config, files2update=[],files2clean=[]):
	if (config['verbose'] == 1):
		print('scanning '+jail+dir)
	for file in os.listdir(jail+dir):
#		print('test if '+dir+file+' or '+jail+dir+file+' exists in ',skips)
		if ((dir+file in skips) or (jail+dir+file in skips)):
			print('skip '+jail+dir+file)
		else:
			try:
				sbuf = os.lstat(dir+file)
				if (stat.S_ISDIR(sbuf[stat.ST_MODE])):
					files2update, files2clean = find2update(jail, dir+file+'/', skips, config, files2update, files2clean)
				elif (stat.S_ISREG(sbuf[stat.ST_MODE])):
					if (config['verbose'] == 1):
						print('checking '+jail+dir+file+'')
					ret = need_update(dir+file, jail+dir+file, origstatbuf=sbuf)
					if (ret == 1):
						files2update.append(dir+file)
					elif (ret == 2):
						files2clean.append(dir+file) 
			except OSError as e:
				errno, strerror = e.args
				if (errno == 2):
					if (os.path.isdir(jail+dir+file)):
						files2update, files2clean = find2update(jail, dir+file+'/', skips, config, files2update, files2clean)
					
					files2clean.append(dir+file)
				else:
					sys.stderr.write('ERROR: while checking if '+jail+dir+file+' needs to be updated: '+strerror+'\n')
	return files2update,files2clean

def updatejail(jail, dirs, skips, config):
	jaillen = len(jail)
	allfiles = []
	allcleans = []
	for dir in dirs:
		if (dir[:jaillen] == jail):
			dir = dir[jaillen:]
		if (dir[-1:] != '/'):
			dir += '/'
		dirnoslash = dir[:-1]
		#print('test if '+dirnoslash+' or '+jail+dirnoslash+' exists in ',skips)
		if ((dirnoslash in skips) or (jail+dirnoslash in skips)):
			print('skip '+jail+dir)
		else:
			files = []
			cleans = []
			cdirs = []
			try:
				files,cleans = find2update(jail, dir, skips, config, [],[])
			except OSError as e:
				_, strerror = e.args
				sys.stderr.write('ERROR:  while scanning dir '+jail+dir+': '+strerror+'\n')
			for file in files:
				if (config['dry-run'] == 1):
					allfiles.append(file)
				else:
					print('removing outdated file '+jail+file)
					try:
						os.unlink(jail+file)
						allfiles.append(file)
					except:
						sys.stderr.write('ERROR: failed to remove outdated file '+jail+file+'\n')
			for file in cleans:
				if (config['dry-run'] == 1):
					allcleans.append(file)
				else:
					if (os.path.isdir(jail+file)):
						cdirs.append(file)
					else:
						print('removing deprecated file '+jail+file)
						try:
							os.unlink(jail+file)
							allcleans.append(file)
						except:
							sys.stderr.write('ERROR: failed to remove deprecated file '+jail+file+'\n')
			for cdir in cdirs:
				if (config['dry-run'] == 1):
					allcleans.append(cdir)
				else:
					print('removing deprecated directory '+jail+file)
					try:
						os.rmdir(jail+cdir)
						allcleans.append(cdir)
					except:
						sys.stderr.write('ERROR: failed to remove deprecated directory '+jail+file+'\n')
	if (config['dry-run'] == 1):
		for file in allfiles:
			print('will update outdated file '+jail+file)
		for file in allcleans:
			print('will remove deprecated file '+jail+file)
	else:
		handled = jk_lib.copy_binaries_and_libs(jail,allfiles, 0, config['verbose'], try_hardlink=config['hardlink'])
		if (len(handled)>0):
			jk_lib.gen_library_cache(jail)

def usage():
	print('')
	print("Usage: "+sys.argv[0]+" [OPTIONS] [DIRECTORIES]")
	print('-h|--help          : this message')
	print('-v|--verbose       : give verbose output')
	print('-c|--configsection=: use options specified in section of config file')
	print('-j|--jail=         : the jail to update')
	print('-d|--dry-run       : show what will be done')
	print('-s|--skip=         : skip file, option can be used multiple times')
	print('-k|--hardlink      : use hardlinks if possible')
	print('')
	print('if no directories are specified, jk_update will scan /bin /usr /lib and /opt')
	print('')

def main():
	try:
		opts, args = getopt.getopt(sys.argv[1:], 'hvdj:s:kc:', ['help', 'verbose', 'dry-run', 'jail=', 'skip=', 'hardlink', 'configsection='])
	except getopt.GetoptError:
		usage()
		sys.exit(1)
	config = {}
	config['verbose'] = 0
	config['dry-run'] = 0
	jail = None
	configsection = None
	dirs = []
	skips = []
	for o, a in opts:
		if o in ("-c", "--configsection"):
			configsection = a
		if o in ("-h", "--help"):
			usage()
			sys.exit()
		elif o in ("-v", "--verbose"):
			config['verbose'] = 1
		elif o in ("-d", "--dry-run"):
			config['dry-run'] = 1
		elif o in ("-s", "--skip"):
		# the name in skips will never have a slash, whether it is a file or a dir
			if (os.path.isdir(a) and (a[-1:] == '/')):
				tmp = a[:-1]
			else:
				tmp = a
			skips.append(tmp)
		elif o in ("-j", "--jail"):
			jail = a
		elif o in ("-k", "--hardlink"):
			config['hardlink'] = 1
	if (jail != None and configsection != None):
		sys.stderr.write('ERROR: cannot specify both a jail and a configsection\n')
		sys.exit(21)
	if (jail == None and configsection == None):
		sys.stderr.write('ERROR: must at least specify a jail or a configsection using\n -j or --jail or -c or --configsection\n\n')
		sys.exit(1)
	if (len(args)>0):
		dirs = args
	
	if (configsection != None):
		cfile = INIPREFIX+'/jk_update.ini'
		jail = configsection
		cfg = ConfigParser()
		cfg.read(cfile)
		if (not cfg.has_section(configsection)):
			sys.stderr.write('ERROR: configfile '+cfile+' does not have a section called '+configsection+'\n')
			sys.exit(1)
		tmp = jk_lib.config_get_option_as_list(cfg,configsection,'skips')
		for entry in tmp:
			skips.append(entry)
		if (not config.has_key('hardlink') and cfg.has_option(configsection,'hardlink')):
			try:
				tmp = int(cfg.get(section,'hardlink'))
				config['hardlink'] = tmp
			except:
				pass
		tmp = jk_lib.config_get_option_as_list(cfg,configsection,'directories')
		for entry in tmp:
			dirs.append(entry)
	if (not config.has_key('hardlink')):
		config['hardlink'] = 0
	if (jail[-1:]=='/'):
		jail = jail[:-1]
	if (dirs == None or len(dirs)==0):
		dirs = ['/bin/', '/lib/', '/usr/', '/opt/']
	# all directories in 'skips' should be without slash
	newskips = []
	for entry in skips:
		if (entry[-1] == '/'):
			newskips.append(entry[:-1])
		else:
			newskips.append(entry)
	skips = newskips
	
	updatejail(jail, dirs, skips, config)

if __name__ == "__main__":
    main()