convert: readd --filemap
To handle merges correctly, this revision adds a filemap_source class
that wraps a converter_source and does the work necessary to calculate
the subgraph we're interested in.
The wrapped converter_source must provide a new getchangedfiles method
that, given a revision rev, and an index N, returns the list of files
that are different in rev and its Nth parent.
The implementation depends on the ability to skip some revisions and to
change the parents field of the commit objects that we returned earlier.
To make the conversion restartable, we assume the revisons in the
revmapfile are topologically sorted.
"""
changegroup.py - Mercurial changegroup manipulation functions
Copyright 2006 Matt Mackall <mpm@selenic.com>
This software may be used and distributed according to the terms
of the GNU General Public License, incorporated herein by reference.
"""
from i18n import _
import struct, os, bz2, zlib, util, tempfile
def getchunk(source):
"""get a chunk from a changegroup"""
d = source.read(4)
if not d:
return ""
l = struct.unpack(">l", d)[0]
if l <= 4:
return ""
d = source.read(l - 4)
if len(d) < l - 4:
raise util.Abort(_("premature EOF reading chunk"
" (got %d bytes, expected %d)")
% (len(d), l - 4))
return d
def chunkiter(source):
"""iterate through the chunks in source"""
while 1:
c = getchunk(source)
if not c:
break
yield c
def chunkheader(length):
"""build a changegroup chunk header"""
return struct.pack(">l", length + 4)
def closechunk():
return struct.pack(">l", 0)
class nocompress(object):
def compress(self, x):
return x
def flush(self):
return ""
bundletypes = {
"": ("", nocompress),
"HG10UN": ("HG10UN", nocompress),
"HG10BZ": ("HG10", lambda: bz2.BZ2Compressor()),
"HG10GZ": ("HG10GZ", lambda: zlib.compressobj()),
}
def writebundle(cg, filename, bundletype):
"""Write a bundle file and return its filename.
Existing files will not be overwritten.
If no filename is specified, a temporary file is created.
bz2 compression can be turned off.
The bundle file will be deleted in case of errors.
"""
fh = None
cleanup = None
try:
if filename:
fh = open(filename, "wb")
else:
fd, filename = tempfile.mkstemp(prefix="hg-bundle-", suffix=".hg")
fh = os.fdopen(fd, "wb")
cleanup = filename
header, compressor = bundletypes[bundletype]
fh.write(header)
z = compressor()
# parse the changegroup data, otherwise we will block
# in case of sshrepo because we don't know the end of the stream
# an empty chunkiter is the end of the changegroup
empty = False
while not empty:
empty = True
for chunk in chunkiter(cg):
empty = False
fh.write(z.compress(chunkheader(len(chunk))))
pos = 0
while pos < len(chunk):
next = pos + 2**20
fh.write(z.compress(chunk[pos:next]))
pos = next
fh.write(z.compress(closechunk()))
fh.write(z.flush())
cleanup = None
return filename
finally:
if fh is not None:
fh.close()
if cleanup is not None:
os.unlink(cleanup)
def readbundle(fh, fname):
header = fh.read(6)
if not header.startswith("HG"):
raise util.Abort(_("%s: not a Mercurial bundle file") % fname)
elif not header.startswith("HG10"):
raise util.Abort(_("%s: unknown bundle version") % fname)
if header == "HG10BZ":
def generator(f):
zd = bz2.BZ2Decompressor()
zd.decompress("BZ")
for chunk in util.filechunkiter(f, 4096):
yield zd.decompress(chunk)
return util.chunkbuffer(generator(fh))
elif header == "HG10UN":
return fh
raise util.Abort(_("%s: unknown bundle compression type")
% fname)