tests/md5sum.py

exchangev2: use filesdata

filesdata is a more efficient mechanism for bulk fetching files data for a
range of changesets. Let's use it in exchangev2.

With this change, a client performing a full clone of mozilla-unified
transmits substantially fewer bytes across the wire:

before: 139,124,863 bytes sent
after:   20,522,499 bytes sent

The bulk of the remaining bytes is likely the transfer of ~1M nodes for
changesets and manifests. We can eliminate this by making requests in
terms of node ranges instead of explicit node lists...

Differential Revision: https://phab.mercurial-scm.org/D4982

#!/usr/bin/env python
#
# Based on python's Tools/scripts/md5sum.py
#
# This software may be used and distributed according to the terms
# of the PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2, which is
# GPL-compatible.

from __future__ import absolute_import

import hashlib
import os
import sys

try:
    import msvcrt
    msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
    msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
except ImportError:
    pass

for filename in sys.argv[1:]:
    try:
        fp = open(filename, 'rb')
    except IOError as msg:
        sys.stderr.write('%s: Can\'t open: %s\n' % (filename, msg))
        sys.exit(1)

    m = hashlib.md5()
    try:
        for data in iter(lambda: fp.read(8192), b''):
            m.update(data)
    except IOError as msg:
        sys.stderr.write('%s: I/O error: %s\n' % (filename, msg))
        sys.exit(1)
    sys.stdout.write('%s  %s\n' % (m.hexdigest(), filename))

sys.exit(0)