aboutsummaryrefslogtreecommitdiff
path: root/build/scripts/install-sysroot.py
blob: 898cc7ce5b8e4b21dcc49ee484ca792cbff34065 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
#!/usr/bin/env python3

# Copyright 2019 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""
Install Debian sysroots for cross compiling Open Screen.
"""

# The sysroot is needed to ensure that binaries that get built will run on
# the oldest stable version of Debian that we currently support.
# This script can be run manually but is more often run as part of gclient
# hooks. When run from hooks this script is a no-op on non-linux platforms.

# The sysroot image could be constructed from scratch based on the current state
# of the Debian archive but for consistency we use a pre-built root image (we
# don't want upstream changes to Debian to affect the build until we
# choose to pull them in). The sysroot images are stored in Chrome's common
# data storage, and the sysroots.json file should be kept in sync with Chrome's
# copy of it.

from __future__ import print_function

import hashlib
import json
import platform
import argparse
import os
import re
import shutil
import subprocess
import sys
try:
    # For Python 3.0 and later
    from urllib.request import urlopen
except ImportError:
    # Fall back to Python 2's urllib2
    from urllib2 import urlopen

SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
PARENT_DIR = os.path.dirname(SCRIPT_DIR)
URL_PREFIX = 'https://storage.googleapis.com'
URL_PATH = 'openscreen-sysroots'

VALID_ARCHS = ('arm', 'arm64')
VALID_PLATFORMS = ('stretch', 'sid')


class Error(Exception):
    pass


def GetSha1(filename):
    """Generates a SHA1 hash for validating download. Done in chunks to avoid
    excess memory usage."""
    BLOCKSIZE = 1024 * 1024
    sha1 = hashlib.sha1()
    with open(filename, 'rb') as f:
        chunk = f.read(BLOCKSIZE)
        while chunk:
            sha1.update(chunk)
            chunk = f.read(BLOCKSIZE)
    return sha1.hexdigest()


def GetSysrootDict(target_platform, target_arch):
    """Gets the sysroot information for a given platform and arch from the
       sysroots.json file."""
    if target_arch not in VALID_ARCHS:
        raise Error('Unknown architecture: %s' % target_arch)

    sysroots_file = os.path.join(SCRIPT_DIR, 'sysroots.json')
    sysroots = json.load(open(sysroots_file))
    sysroot_key = '%s_%s' % (target_platform, target_arch)
    if sysroot_key not in sysroots:
        raise Error('No sysroot for: %s' % (sysroot_key))
    return sysroots[sysroot_key]


def DownloadFile(url, local_path):
    """Uses urllib to download a remote file into local_path."""
    for _ in range(3):
        try:
            response = urlopen(url)
            with open(local_path, "wb") as f:
                f.write(response.read())
            break
        except Exception:
            pass
    else:
        raise Error('Failed to download %s' % url)

def ValidateFile(local_path, expected_sum):
    """Generates the SHA1 hash of a local file to compare with an expected
       hashsum."""
    sha1sum = GetSha1(local_path)
    if sha1sum != expected_sum:
        raise Error('Tarball sha1sum is wrong.'
                    'Expected %s, actual: %s' % (expected_sum, sha1sum))

def InstallSysroot(target_platform, target_arch):
    """Downloads, validates, unpacks, and installs a sysroot image."""
    sysroot_dict = GetSysrootDict(target_platform, target_arch)
    tarball_filename = sysroot_dict['Tarball']
    tarball_sha1sum = sysroot_dict['Sha1Sum']

    sysroot = os.path.join(PARENT_DIR, sysroot_dict['SysrootDir'])

    url = '%s/%s/%s/%s' % (URL_PREFIX, URL_PATH, tarball_sha1sum,
                           tarball_filename)

    stamp = os.path.join(sysroot, '.stamp')
    if os.path.exists(stamp):
        with open(stamp) as s:
            if s.read() == url:
                return

    if os.path.isdir(sysroot):
        shutil.rmtree(sysroot)
    os.mkdir(sysroot)

    tarball_path = os.path.join(sysroot, tarball_filename)
    DownloadFile(url, tarball_path)
    ValidateFile(tarball_path, tarball_sha1sum)
    subprocess.check_call(['tar', 'xf', tarball_path, '-C', sysroot])
    os.remove(tarball_path)

    with open(stamp, 'w') as s:
        s.write(url)


def parse_args(args):
    """Parses the passed in arguments into an object."""
    p = argparse.ArgumentParser()
    p.add_argument(
        'arch',
        help='Sysroot architecture: %s' % ', '.join(VALID_ARCHS))
    p.add_argument(
        'platform',
        help='Sysroot platform: %s' % ', '.join(VALID_PLATFORMS))
    p.add_argument(
        '--print-hash', action="store_true",
        help='Print the hash of the sysroot for the specified arch.')

    return p.parse_args(args)


def main(args):
    if not (sys.platform.startswith('linux') or sys.platform == 'darwin'):
        print('Unsupported platform. Only Linux and Mac OS X are supported.')
        return 1

    parsed_args = parse_args(args)
    if parsed_args.print_hash:
        print(GetSysrootDict(parsed_args.platform, parsed_args.arch)['Sha1Sum'])

    InstallSysroot(parsed_args.platform, parsed_args.arch)
    return 0


if __name__ == '__main__':
    try:
        sys.exit(main(sys.argv[1:]))
    except Error as e:
        sys.stderr.write('Installing sysroot error: {}\n'.format(e))
        sys.exit(1)