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Diffstat (limited to 'eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/hgext/relink.py')
| -rw-r--r-- | eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/hgext/relink.py | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/hgext/relink.py b/eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/hgext/relink.py new file mode 100644 index 0000000..77bd3c3 --- /dev/null +++ b/eggs/mercurial-1.7.3-py2.6-linux-x86_64.egg/hgext/relink.py @@ -0,0 +1,180 @@ +# Mercurial extension to provide 'hg relink' command +# +# Copyright (C) 2007 Brendan Cully <brendan@kublai.com> +# +# This software may be used and distributed according to the terms of the +# GNU General Public License version 2 or any later version. + +"""recreates hardlinks between repository clones""" + +from mercurial import hg, util +from mercurial.i18n import _ +import os, stat + +def relink(ui, repo, origin=None, **opts): + """recreate hardlinks between two repositories + + When repositories are cloned locally, their data files will be + hardlinked so that they only use the space of a single repository. + + Unfortunately, subsequent pulls into either repository will break + hardlinks for any files touched by the new changesets, even if + both repositories end up pulling the same changes. + + Similarly, passing --rev to "hg clone" will fail to use any + hardlinks, falling back to a complete copy of the source + repository. + + This command lets you recreate those hardlinks and reclaim that + wasted space. + + This repository will be relinked to share space with ORIGIN, which + must be on the same local disk. If ORIGIN is omitted, looks for + "default-relink", then "default", in [paths]. + + Do not attempt any read operations on this repository while the + command is running. (Both repositories will be locked against + writes.) + """ + if not hasattr(util, 'samefile') or not hasattr(util, 'samedevice'): + raise util.Abort(_('hardlinks are not supported on this system')) + src = hg.repository( + hg.remoteui(repo, opts), + ui.expandpath(origin or 'default-relink', origin or 'default')) + if not src.local(): + raise util.Abort('must specify local origin repository') + ui.status(_('relinking %s to %s\n') % (src.store.path, repo.store.path)) + locallock = repo.lock() + try: + remotelock = src.lock() + try: + candidates = sorted(collect(src, ui)) + targets = prune(candidates, src.store.path, repo.store.path, ui) + do_relink(src.store.path, repo.store.path, targets, ui) + finally: + remotelock.release() + finally: + locallock.release() + +def collect(src, ui): + seplen = len(os.path.sep) + candidates = [] + live = len(src['tip'].manifest()) + # Your average repository has some files which were deleted before + # the tip revision. We account for that by assuming that there are + # 3 tracked files for every 2 live files as of the tip version of + # the repository. + # + # mozilla-central as of 2010-06-10 had a ratio of just over 7:5. + total = live * 3 // 2 + src = src.store.path + pos = 0 + ui.status(_("tip has %d files, estimated total number of files: %s\n") + % (live, total)) + for dirpath, dirnames, filenames in os.walk(src): + dirnames.sort() + relpath = dirpath[len(src) + seplen:] + for filename in sorted(filenames): + if not filename[-2:] in ('.d', '.i'): + continue + st = os.stat(os.path.join(dirpath, filename)) + if not stat.S_ISREG(st.st_mode): + continue + pos += 1 + candidates.append((os.path.join(relpath, filename), st)) + ui.progress(_('collecting'), pos, filename, _('files'), total) + + ui.progress(_('collecting'), None) + ui.status(_('collected %d candidate storage files\n') % len(candidates)) + return candidates + +def prune(candidates, src, dst, ui): + def linkfilter(src, dst, st): + try: + ts = os.stat(dst) + except OSError: + # Destination doesn't have this file? + return False + if util.samefile(src, dst): + return False + if not util.samedevice(src, dst): + # No point in continuing + raise util.Abort( + _('source and destination are on different devices')) + if st.st_size != ts.st_size: + return False + return st + + targets = [] + total = len(candidates) + pos = 0 + for fn, st in candidates: + pos += 1 + srcpath = os.path.join(src, fn) + tgt = os.path.join(dst, fn) + ts = linkfilter(srcpath, tgt, st) + if not ts: + ui.debug(_('not linkable: %s\n') % fn) + continue + targets.append((fn, ts.st_size)) + ui.progress(_('pruning'), pos, fn, _('files'), total) + + ui.progress(_('pruning'), None) + ui.status(_('pruned down to %d probably relinkable files\n') % len(targets)) + return targets + +def do_relink(src, dst, files, ui): + def relinkfile(src, dst): + bak = dst + '.bak' + os.rename(dst, bak) + try: + util.os_link(src, dst) + except OSError: + os.rename(bak, dst) + raise + os.remove(bak) + + CHUNKLEN = 65536 + relinked = 0 + savedbytes = 0 + + pos = 0 + total = len(files) + for f, sz in files: + pos += 1 + source = os.path.join(src, f) + tgt = os.path.join(dst, f) + # Binary mode, so that read() works correctly, especially on Windows + sfp = file(source, 'rb') + dfp = file(tgt, 'rb') + sin = sfp.read(CHUNKLEN) + while sin: + din = dfp.read(CHUNKLEN) + if sin != din: + break + sin = sfp.read(CHUNKLEN) + sfp.close() + dfp.close() + if sin: + ui.debug(_('not linkable: %s\n') % f) + continue + try: + relinkfile(source, tgt) + ui.progress(_('relinking'), pos, f, _('files'), total) + relinked += 1 + savedbytes += sz + except OSError, inst: + ui.warn('%s: %s\n' % (tgt, str(inst))) + + ui.progress(_('relinking'), None) + + ui.status(_('relinked %d files (%d bytes reclaimed)\n') % + (relinked, savedbytes)) + +cmdtable = { + 'relink': ( + relink, + [], + _('[ORIGIN]') + ) +} |