Linux: Add a script to generate a Precise dpkg admin dir for use with official builds on Trusty.

chrome/installer/linux/sysroot_scripts/generate_precise_dpkg_admin_dir.py

Index: chrome/installer/linux/sysroot_scripts/generate_precise_dpkg_admin_dir.py
diff --git a/chrome/installer/linux/sysroot_scripts/generate_precise_dpkg_admin_dir.py b/chrome/installer/linux/sysroot_scripts/generate_precise_dpkg_admin_dir.py
new file mode 100755
index 0000000000000000000000000000000000000000..af57926ff1a5c31c0f23cbd608acc00d99e8eb8c
--- /dev/null
+++ b/chrome/installer/linux/sysroot_scripts/generate_precise_dpkg_admin_dir.py
@@ -0,0 +1,165 @@
+#!/usr/bin/env python
+# Copyright 2014 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.
+
+# Takes in a Ubuntu Precise dpkg admin directory (typically /var/lib/dpkg) and
+# outputs a dpkg admin directory appropriate for use with dpkg-shlibdeps on
+# Ubuntu Trusty.
+#
+# Example usage:
+#   generate_precise_dpkg_admin_dir.py --arch i386 \
+#       /path/to/precise_32-bit_chroot/var/lib/dpkg /path/to/dest_dir
+
+import optparse
+import os
+import shutil
+import string
+import sys
+
+
+SCRIPT_DIR = os.path.dirname(os.path.abspath(__file__))
+PACKAGES = [

[Paweł Hajdan Jr., 2014/12/08 10:12:15]

Can we de-duplicate the list of packages between this script and the
sysroot-generating script?

+    "libasound2",
+    "libc6",
+    "libcairo2",
+    "libcups2",
+    "libdbus-1-3",
+    "libexpat1",
+    "libfontconfig1",
+    "libfreetype6",
+    "libgconf-2-4",
+    "libgdk-pixbuf2.0-0",
+    "libglib2.0-0",
+    "libgtk2.0-0",
+    "libnspr4",
+    "libnss3",
+    "libpango-1.0-0",
+    "libpangocairo-1.0-0",
+    "libstdc++6",
+    "libx11-6",
+    "libxcomposite1",
+    "libxcursor1",
+    "libxdamage1",
+    "libxext6",
+    "libxfixes3",
+    "libxi6",
+    "libxrandr2",
+    "libxrender1",
+    "libxss1",
+    "libxtst6",
+]
+
+
+def ParseStatusFile(status_file):
+  package_map = {}
+  lines = open(status_file).readlines()
+  current_package_name = ''
+  current_package_data = ''
+  for line in lines:
+    if (not line or
+        line[0] not in string.ascii_uppercase or
+        line.startswith('Homepage: ') or
+        line.startswith('Original-Maintainer: ')):
+      continue
+    if line.startswith('Package: '):
+      if current_package_name:
+        package_map[current_package_name] = current_package_data
+      current_package_name = line[len('Package: '):].strip()
+      current_package_data = ''
+      # Hack for libpango1.0-0 vs libpango-1.0-0

[Paweł Hajdan Jr., 2014/12/08 10:12:15]

Could you explain more why we need this hack? If possible I'd really like to
understand entire background behind it.

+      if current_package_name == 'libpango1.0-0':
+        current_package_name = 'libpango-1.0-0'
+    else:
+      current_package_data += line
+
+  # Hack for libpangocairo-1.0-0

[Paweł Hajdan Jr., 2014/12/08 10:12:15]

Same here, I'm really surprised we'd need this.

Can we simplify things if we require Precise for running this script?

Or is compiling on Trusty a problem if we don't apply the hacks?

+  if 'libpango-1.0-0' in package_map:
+    assert('libpangocairo-1.0-0' not in package_map)
+    package_map['libpangocairo-1.0-0'] = package_map['libpango-1.0-0']
+  return package_map
+
+
+def main():
+  if options.arch not in ['amd64', 'i386']:

[Paweł Hajdan Jr., 2014/12/08 10:12:15]

At least argparse has built-in ways to validate that a value belongs to a set of
choices. Please consider using that.

+    print 'Unknown architecture: %s' % options.arch
+    return 1
+
+  if len(args) != 2:
+    print 'Wrong number of arguments.'
+    return 1
+
+  src_dir = args[0]
+  dest_dir = args[1]
+
+  src_status_file = os.path.join(src_dir, 'status')
+  src_info_dir = os.path.join(src_dir, 'info')
+  src_info_format_file = os.path.join(src_info_dir, 'format')
+  src_triggers_dir = os.path.join(src_dir, 'triggers')
+  src_updates_dir = os.path.join(src_dir, 'updates')
+  if not os.path.isfile(src_status_file):
+    print 'status file not found. (%s)' % src_status_file
+    return 1
+  if not os.path.isdir(src_info_dir):
+    print 'info dir not found. (%s)' % src_info_dir
+    return 1
+  if not os.path.isfile(src_info_format_file):
+    print 'info format file not found. (%s)' % src_info_format_file
+    return 1
+  if not os.path.isdir(src_triggers_dir):
+    print 'triggers dir not found. (%s)' % src_triggers_dir
+    return 1
+  if not os.path.isdir(src_updates_dir):
+    print 'updates dir not found. (%s)' % src_updates_dir
+    return 1
+
+  package_map = ParseStatusFile(src_status_file)
+  missing_packages = []
+  for package in PACKAGES:
+    if package not in package_map:
+      missing_packages.append(package)
+  if missing_packages:
+    print 'Missing packages: %s' % ','.join(missing_packages)
+    return 1
+
+  dest_status_file = os.path.join(dest_dir, 'status')
+  dest_info_dir = os.path.join(dest_dir, 'info')
+  dest_info_format_file = os.path.join(dest_info_dir, 'format')
+  dest_triggers_dir = os.path.join(dest_dir, 'triggers')
+  dest_updates_dir = os.path.join(dest_dir, 'updates')
+
+  os.makedirs(dest_info_dir)
+  shutil.copy(src_info_format_file, dest_info_format_file)
+  shutil.copytree(src_triggers_dir, dest_triggers_dir,
+                  ignore=shutil.ignore_patterns('Lock'))
+  shutil.copytree(src_updates_dir, dest_updates_dir)
+
+  dest_status_file_handle = open(dest_status_file, 'w')
+  for package in PACKAGES:
+    dest_status_file_handle.write('Package: %s\n' % package)
+    dest_status_file_handle.write(package_map[package])
+    dest_status_file_handle.write('\n')
+  dest_status_file_handle.close()

[Paweł Hajdan Jr., 2014/12/08 10:12:15]

nit: Why not just "with open(...) as ..."?

+
+  for package in PACKAGES:
+    for extension in ('shlibs', 'symbols'):
+      dest_filename = '%s:%s.%s' % (package, options.arch, extension)
+      # Hack for libpango
+      if (package == 'libpango-1.0-0' or package == 'libpangocairo-1.0-0'):
+        src_filename = 'libpango1.0-0:%s.%s' % (options.arch, extension)
+      else:
+        src_filename = dest_filename
+      src_file = os.path.join(src_info_dir, src_filename)
+      dest_file = os.path.join(dest_info_dir, dest_filename)
+      if not os.path.isfile(src_file):
+        continue
+      shutil.copy(src_file, dest_file)
+
+  return 0
+
+
+if __name__ == '__main__':
+  parser = optparse.OptionParser('usage: %prog --arch ARCH SRC DEST')
+  parser.add_option('--arch', help='Sysroot architecture: i386 or amd64')
+  options, args = parser.parse_args()
+  sys.exit(main())