Usage: binhost-snapshot [options] <src_pkg_dir> <snapshot_dir> <snapshot_uri> <binhos...

This program will copy src_pkg_dir to snapshot_dir and inside
binhost_dir it will create a Packages index file which refers to
snapshot_uri. This is intended to solve race conditions on binhosts as
described at http://crosbug.com/3225.

Required Arguments:

  src_pkg_dir  - the source $PKGDIR
  snapshot_dir - destination snapshot directory (must not exist)
  snapshot_uri - URI which refers to snapshot_dir from the
                 client side
  binhost_dir  - directory in which to write Packages index with
                 snapshot_uri

Options:
  -h, --help            show this help message and exit
  --hardlinks=HARDLINKS
                        create hardlinks (y or n, default is y)

diff --git a/bin/binhost-snapshot b/bin/binhost-snapshot
new file mode 100755 (executable)
index 0000000..825a116
--- /dev/null
+++ b/bin/binhost-snapshot
@@ -0,0 +1,142 @@
+#!/usr/bin/python
+# Copyright 2010 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+import codecs
+import optparse
+import os
+import sys
+import textwrap
+
+try:
+       from urllib.parse import urlparse
+except ImportError:
+       from urlparse import urlparse
+
+try:
+       import portage
+except ImportError:
+       from os import path as osp
+       sys.path.insert(0, osp.join(osp.dirname(osp.dirname(
+               osp.realpath(__file__))), "pym"))
+       import portage
+
+def parse_args(argv):
+       prog_name = os.path.basename(argv[0])
+       usage = prog_name + ' [options] ' + \
+               '<src_pkg_dir> <snapshot_dir> <snapshot_uri> <binhost_dir>'
+
+       prog_desc = "This program will copy src_pkg_dir to snapshot_dir " + \
+               "and inside binhost_dir it will create a Packages index file " + \
+               "which refers to snapshot_uri. This is intended to solve race " + \
+               "conditions on binhosts as described at http://crosbug.com/3225."
+
+       usage += "\n\n"
+       for line in textwrap.wrap(prog_desc, 70):
+               usage += line + "\n" 
+
+       usage += "\n"
+       usage += "Required Arguments:\n\n"
+       usage += "  src_pkg_dir  - the source $PKGDIR\n"
+       usage += "  snapshot_dir - destination snapshot " + \
+               "directory (must not exist)\n"
+       usage += "  snapshot_uri - URI which refers to " + \
+               "snapshot_dir from the\n" + \
+               "                 client side\n"
+       usage += "  binhost_dir  - directory in which to " + \
+               "write Packages index with\n" + \
+               "                 snapshot_uri"
+
+       parser = optparse.OptionParser(usage=usage)
+       parser.add_option('--hardlinks', help='create hardlinks (y or n, default is y)',
+               choices=('y', 'n'))
+       parser.set_defaults(hardlinks='y')
+       options, args = parser.parse_args(argv[1:])
+
+       if len(args) != 4:
+               parser.error("Required 4 arguments, got %d" % (len(args),))
+
+       return parser, options, args
+
+def main(argv):
+       parser, options, args = parse_args(argv)
+
+       src_pkg_dir, snapshot_dir, snapshot_uri, binhost_dir = args
+       src_pkgs_index = os.path.join(src_pkg_dir, 'Packages')
+
+       if not os.path.isdir(src_pkg_dir):
+               parser.error("src_pkg_dir is not a directory: '%s'" % (src_pkg_dir,))
+
+       if not os.path.isfile(src_pkgs_index):
+               parser.error("src_pkg_dir does not contain a " + \
+                       "'Packages' index: '%s'" % (src_pkg_dir,))
+
+       parse_result = urlparse(snapshot_uri)
+       if not (parse_result.scheme and parse_result.netloc and parse_result.path):
+               parser.error("snapshot_uri is not a valid URI: '%s'" % (snapshot_uri,))
+
+       if os.path.isdir(snapshot_dir):
+               parser.error("snapshot_dir already exists: '%s'" % snapshot_dir)
+
+       try:
+               os.makedirs(os.path.dirname(snapshot_dir))
+       except OSError:
+               pass
+       if not os.path.isdir(os.path.dirname(snapshot_dir)):
+               parser.error("snapshot_dir parent could not be created: '%s'" % \
+                       os.path.dirname(snapshot_dir))
+
+       try:
+               os.makedirs(binhost_dir)
+       except OSError:
+               pass
+       if not os.path.isdir(binhost_dir):
+               parser.error("binhost_dir could not be created: '%s'" % binhost_dir)
+
+       cp_opts = 'RP'
+       if options.hardlinks == 'n':
+               cp_opts += 'p'
+       else:
+               cp_opts += 'l'
+
+       cp_cmd = 'cp -%s %s %s' % (
+               cp_opts,
+               portage._shell_quote(src_pkg_dir),
+               portage._shell_quote(snapshot_dir)
+       )
+
+       ret = os.system(cp_cmd)
+       if not (os.WIFEXITED(ret) and os.WEXITSTATUS(ret) == os.EX_OK):
+               return 1
+
+       infile = codecs.open(portage._unicode_encode(src_pkgs_index,
+               encoding=portage._encodings['fs'], errors='strict'),
+               mode='r', encoding=portage._encodings['repo.content'],
+               errors='strict')
+
+       outfile = portage.util.atomic_ofstream(
+               os.path.join(binhost_dir, "Packages"),
+               encoding=portage._encodings['repo.content'],
+               errors='strict')
+
+       for line in infile:
+               if line[:4] == 'URI:':
+                       # skip existing URI line
+                       pass
+               else:
+                       if not line.strip():
+                               # end of header
+                               outfile.write("URI: %s\n\n" % snapshot_uri)
+                               break
+                       outfile.write(line)
+
+       for line in infile:
+               outfile.write(line)
+
+       infile.close()
+       outfile.close()
+
+       return os.EX_OK
+
+if __name__ == "__main__":
+       sys.exit(main(sys.argv))