#!/usr/bin/python

#

# CDDL HEADER START

#

# The contents of this file are subject to the terms of the

# Common Development and Distribution License (the "License").

# You may not use this file except in compliance with the License.

#

# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE

# or http://www.opensolaris.org/os/licensing.

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# When distributing Covered Code, include this CDDL HEADER in each

# file and include the License file at usr/src/OPENSOLARIS.LICENSE.

# If applicable, add the following below this CDDL HEADER, with the

# fields enclosed by brackets "[]" replaced with your own identifying

# information: Portions Copyright [yyyy] [name of copyright owner]

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# Copyright 2008 Sun Microsystems, Inc.  All rights reserved.

# Use is subject to license terms.

import os

import urllib

import urllib2

import urlparse

import httplib

import platform

import re

import sha

import zlib

import pkg.urlhelpers as urlhelpers

import pkg.portable as portable

from pkg.client.imagetypes import img_type_names, IMG_NONE

from pkg import VERSION

def hash_file_name(f):

        """Return the two-level path fragment for the given filename, which is

        assumed to be a content hash of at least 8 distinct characters."""

        return os.path.join("%s" % f[0:2], "%s" % f[2:8], "%s" % f)

def url_affix_trailing_slash(u):

        if u[-1] != '/':

                u = u + '/'

        return u

_client_version = "pkg/%s (%s %s; %s %s; %%s)" % \

    (VERSION, portable.util.get_canonical_os_name(), platform.machine(),

    portable.util.get_os_release(), platform.version())

def versioned_urlopen(base_uri, operation, versions = [], tail = None,

    data = None, headers = {}, ssl_creds = None, imgtype = IMG_NONE):

        """Open the best URI for an operation given a set of versions.

        Both the client and the server may support multiple versions of

        the protocol of a particular operation.  The client will pass

        this method an ordered array of versions it understands, along

        with the base URI and the operation it wants.  This method will

        open the URL corresponding to the best version both the client

        and the server understand, returning a tuple of the open URL and

        the version used on success, and throwing an exception if no

        matching version can be found.

        """

        # Ignore http_proxy for localhost case, by overriding

        # default proxy behaviour of urlopen().

        netloc = urlparse.urlparse(base_uri)[1]

        if not netloc:

                raise ValueError, "Malformed URL: %s" % base_uri

        if urllib.splitport(netloc)[0] == "localhost":

                # XXX cache this opener?

                proxy_handler = urllib2.ProxyHandler({})

                opener_dir = urllib2.build_opener(proxy_handler)

                url_opener = opener_dir.open

        elif ssl_creds and ssl_creds != (None, None):

                cert_handler = urlhelpers.HTTPSCertHandler(

                    key_file = ssl_creds[0], cert_file = ssl_creds[1])

                opener_dir = urllib2.build_opener(cert_handler)

                url_opener = opener_dir.open

        else:

                url_opener = urllib2.urlopen

        for version in versions:

                if base_uri[-1] != '/':

                        base_uri += '/'

                if tail:

                        uri = urlparse.urljoin(base_uri, "%s/%s/%s" % \

                            (operation, version, tail))

                else:

                        uri = urlparse.urljoin(base_uri, "%s/%s" % \

                            (operation, version))

                headers["User-Agent"] = \

                    _client_version % img_type_names[imgtype]

                req = urllib2.Request(url = uri, headers = headers)

                if data is not None:

                        req.add_data(data)

                try:

                        c = url_opener(req)

                except urllib2.HTTPError, e:

                        if e.code != httplib.NOT_FOUND or e.msg != "Version not supported":

                                raise

                        continue

                # XXX catch BadStatusLine and convert to INTERNAL_SERVER_ERROR?

                return c, version

        else:

                # Couldn't find a version that we liked.

                raise RuntimeError, \

                    "%s doesn't speak a known version of %s operation" % \

                    (base_uri, operation)

_hostname_re = re.compile("^[a-zA-Z0-9](?:[a-zA-Z0-9\-]*[a-zA-Z0-9]+\.?)*$")

_invalid_host_chars = re.compile(".*[^a-zA-Z0-9\-\.]+")

_valid_proto = ["http", "https"]

def valid_auth_prefix(prefix):

        """Verify that the authority prefix only contains valid characters."""

        # This is a workaround for the the hostname_re being slow when

        # it comes to finding invalid characters in the prefix string.

        if _invalid_host_chars.match(prefix):

                # prefix bad chars

                return False

        if _hostname_re.match(prefix):

                return True

        return False

def valid_auth_url(url):

        """Verify that the authority URL contains only valid characters."""

        # First split the URL and check if the scheme is one we support

        o = urlparse.urlsplit(url)

        if not o[0] in _valid_proto:

                return False

        # Next verify that the network location is valid

        host, port = urllib.splitport(o[1])

        if not host or _invalid_host_chars.match(host):

                return False

        if _hostname_re.match(host):

                return True

        return False

def gunzip_from_stream(gz, outfile):

        """Decompress a gzipped input stream into an output stream.

        The argument 'gz' is an input stream of a gzipped file (XXX make it do

        either a gzipped file or raw zlib compressed data), and 'outfile' is is

        an output stream.  gunzip_from_stream() decompresses data from 'gz' and

        writes it to 'outfile', and returns the hexadecimal SHA-1 sum of that

        data.

        """

        FHCRC = 2

        FEXTRA = 4

        FNAME = 8

        FCOMMENT = 16

        # Read the header

        magic = gz.read(2)

        if magic != "\037\213":

                raise IOError, "Not a gzipped file"

        method = ord(gz.read(1))

        if method != 8:

                raise IOError, "Unknown compression method"

        flag = ord(gz.read(1))

        gz.read(6) # Discard modtime, extraflag, os

        # Discard an extra field

        if flag & FEXTRA:

                xlen = ord(gz.read(1))

                xlen = xlen + 256 * ord(gz.read(1))

                gz.read(xlen)

        # Discard a null-terminated filename

        if flag & FNAME:

                while True:

                        s = gz.read(1)

                        if not s or s == "\000":

                                break

        # Discard a null-terminated comment

        if flag & FCOMMENT:

                while True:

                        s = gz.read(1)

                        if not s or s == "\000":

                                break

        # Discard a 16-bit CRC

        if flag & FHCRC:

                gz.read(2)

        shasum = sha.new()

        dcobj = zlib.decompressobj(-zlib.MAX_WBITS)

        while True:

                buf = gz.read(64 * 1024)

                if buf == "":

                        ubuf = dcobj.flush()

                        shasum.update(ubuf)

                        outfile.write(ubuf)

                        break

                ubuf = dcobj.decompress(buf)

                shasum.update(ubuf)

                outfile.write(ubuf)

        return shasum.hexdigest()