Mercurial > hg
view mercurial/changegroup.py @ 11791:00cde9bddbe4
repair: do not compress partial bundle if we do not keep it on disk
A partial bundle is created to temporarily save revisions > rev but
not descending from the node to strip, to be able to restore the
changesets after stripping the changelog.
Since this bundle is not kept after the strip operation, and is not
user-visible, it is not necessary and should be faster to avoid
compression.
author | Nicolas Dumazet <nicdumz.commits@gmail.com> |
---|---|
date | Thu, 12 Aug 2010 16:53:23 +0900 |
parents | 801533a52799 |
children | 270fb4d39153 |
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# 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 version 2 or any later version. from i18n import _ import util import struct, os, bz2, zlib, tempfile def getchunk(source): """return the next chunk from changegroup 'source' as a string""" 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, progress=None): """iterate through the chunks in source, yielding a sequence of chunks (strings)""" while 1: c = getchunk(source) if not c: break elif progress is not None: progress() yield c def chunkheader(length): """return a changegroup chunk header (string)""" return struct.pack(">l", length + 4) def closechunk(): """return a changegroup chunk header (string) for a zero-length chunk""" 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 collector(cl, mmfs, files): # Gather information about changeset nodes going out in a bundle. # We want to gather manifests needed and filelogs affected. def collect(node): c = cl.read(node) files.update(c[3]) mmfs.setdefault(c[0], node) return collect # hgweb uses this list to communicate its preferred type bundlepriority = ['HG10GZ', 'HG10BZ', 'HG10UN'] 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 # a changegroup has at least 2 chunkiters (changelog and manifest). # after that, an empty chunkiter is the end of the changegroup empty = False count = 0 while not empty or count <= 2: empty = True count += 1 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 unbundle(header, fh): if header == 'HG10UN': return fh elif not header.startswith('HG'): # old client with uncompressed bundle def generator(f): yield header for chunk in f: yield chunk elif header == 'HG10GZ': def generator(f): zd = zlib.decompressobj() for chunk in f: yield zd.decompress(chunk) elif 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)) def readbundle(fh, fname): header = fh.read(6) if not header.startswith('HG'): raise util.Abort(_('%s: not a Mercurial bundle file') % fname) if not header.startswith('HG10'): raise util.Abort(_('%s: unknown bundle version') % fname) elif header not in bundletypes: raise util.Abort(_('%s: unknown bundle compression type') % fname) return unbundle(header, fh)