convert: add commandline.xargs(), use it in svn_sink class

Introduce commandline.xargs() to limit argument list with respect
to ARG_MAX bytes. If no ARG_MAX information available - use POSIX
required minimum of 4096 bytes.

Under Windows, while actual argument list length is limited to 32k,
shells impose their own limits on command line length, down to 2047 bytes
for cmd.exe under Windows NT/2k and about 2500 bytes for older 4nt.exe.
See http://support.microsoft.com/kb/830473 for details about cmd.exe
limitations.

Since ARG_MAX is limit for argument list and environment, we reserve half
of it and one byte for environment variables. This way with default ARG_MAX
(4096 bytes) we get value 2047 bytes which is OK for Windows too.

hgext/convert/common.py

@@ -1,297 +1,342
 # common code for the convert extension
 import base64, errno
+import os
 import cPickle as pickle
 from mercurial import util
 from mercurial.i18n import _
 
 def encodeargs(args):
     def encodearg(s):
         lines = base64.encodestring(s)
         lines = [l.splitlines()[0] for l in lines]
         return ''.join(lines)
 
     s = pickle.dumps(args)
     return encodearg(s)
 
 def decodeargs(s):
     s = base64.decodestring(s)
     return pickle.loads(s)
 
 def checktool(exe, name=None):
     name = name or exe
     if not util.find_exe(exe):
         raise util.Abort('cannot find required "%s" tool' % name)
 
 class NoRepo(Exception): pass
 
 SKIPREV = 'SKIP'
 
 class commit(object):
     def __init__(self, author, date, desc, parents, branch=None, rev=None,
                  extra={}):
         self.author = author
         self.date = date
         self.desc = desc
         self.parents = parents
         self.branch = branch
         self.rev = rev
         self.extra = extra
 
 class converter_source(object):
     """Conversion source interface"""
 
     def __init__(self, ui, path=None, rev=None):
         """Initialize conversion source (or raise NoRepo("message")
         exception if path is not a valid repository)"""
         self.ui = ui
         self.path = path
         self.rev = rev
 
         self.encoding = 'utf-8'
 
     def before(self):
         pass
 
     def after(self):
         pass
 
     def setrevmap(self, revmap):
         """set the map of already-converted revisions"""
         pass
 
     def getheads(self):
         """Return a list of this repository's heads"""
         raise NotImplementedError()
 
     def getfile(self, name, rev):
         """Return file contents as a string"""
         raise NotImplementedError()
 
     def getmode(self, name, rev):
         """Return file mode, eg. '', 'x', or 'l'"""
         raise NotImplementedError()
 
     def getchanges(self, version):
         """Returns a tuple of (files, copies)
         Files is a sorted list of (filename, id) tuples for all files changed
         in version, where id is the source revision id of the file.
 
         copies is a dictionary of dest: source
         """
         raise NotImplementedError()
 
     def getcommit(self, version):
         """Return the commit object for version"""
         raise NotImplementedError()
 
     def gettags(self):
         """Return the tags as a dictionary of name: revision"""
         raise NotImplementedError()
 
     def recode(self, s, encoding=None):
         if not encoding:
             encoding = self.encoding or 'utf-8'
 
         if isinstance(s, unicode):
             return s.encode("utf-8")
         try:
             return s.decode(encoding).encode("utf-8")
         except:
             try:
                 return s.decode("latin-1").encode("utf-8")
             except:
                 return s.decode(encoding, "replace").encode("utf-8")
 
     def getchangedfiles(self, rev, i):
         """Return the files changed by rev compared to parent[i].
 
         i is an index selecting one of the parents of rev.  The return
         value should be the list of files that are different in rev and
         this parent.
 
         If rev has no parents, i is None.
 
         This function is only needed to support --filemap
         """
         raise NotImplementedError()
 
     def converted(self, rev, sinkrev):
         '''Notify the source that a revision has been converted.'''
         pass
 
 
 class converter_sink(object):
     """Conversion sink (target) interface"""
 
     def __init__(self, ui, path):
         """Initialize conversion sink (or raise NoRepo("message")
         exception if path is not a valid repository)
 
         created is a list of paths to remove if a fatal error occurs
         later"""
         self.ui = ui
         self.path = path
         self.created = []
 
     def getheads(self):
         """Return a list of this repository's heads"""
         raise NotImplementedError()
 
     def revmapfile(self):
         """Path to a file that will contain lines
         source_rev_id sink_rev_id
         mapping equivalent revision identifiers for each system."""
         raise NotImplementedError()
 
     def authorfile(self):
         """Path to a file that will contain lines
         srcauthor=dstauthor
         mapping equivalent authors identifiers for each system."""
         return None
 
     def putfile(self, f, e, data):
         """Put file for next putcommit().
         f: path to file
         e: '', 'x', or 'l' (regular file, executable, or symlink)
         data: file contents"""
         raise NotImplementedError()
 
     def delfile(self, f):
         """Delete file for next putcommit().
         f: path to file"""
         raise NotImplementedError()
 
     def putcommit(self, files, parents, commit):
         """Create a revision with all changed files listed in 'files'
         and having listed parents. 'commit' is a commit object containing
         at a minimum the author, date, and message for this changeset.
         Called after putfile() and delfile() calls. Note that the sink
         repository is not told to update itself to a particular revision
         (or even what that revision would be) before it receives the
         file data."""
         raise NotImplementedError()
 
     def puttags(self, tags):
         """Put tags into sink.
         tags: {tagname: sink_rev_id, ...}"""
         raise NotImplementedError()
 
     def setbranch(self, branch, pbranch, parents):
         """Set the current branch name. Called before the first putfile
         on the branch.
         branch: branch name for subsequent commits
         pbranch: branch name of parent commit
         parents: destination revisions of parent"""
         pass
 
     def setfilemapmode(self, active):
         """Tell the destination that we're using a filemap
 
         Some converter_sources (svn in particular) can claim that a file
         was changed in a revision, even if there was no change.  This method
         tells the destination that we're using a filemap and that it should
         filter empty revisions.
         """
         pass
 
     def before(self):
         pass
 
     def after(self):
         pass
 
 
 class commandline(object):
     def __init__(self, ui, command):
         self.ui = ui
         self.command = command
 
     def prerun(self):
         pass
 
     def postrun(self):
         pass
 
-    def _run(self, cmd, *args, **kwargs):
+    def _cmdline(self, cmd, *args, **kwargs):
         cmdline = [self.command, cmd] + list(args)
         for k, v in kwargs.iteritems():
             if len(k) == 1:
                 cmdline.append('-' + k)
             else:
                 cmdline.append('--' + k.replace('_', '-'))
             try:
                 if len(k) == 1:
                     cmdline.append('' + v)
                 else:
                     cmdline[-1] += '=' + v
             except TypeError:
                 pass
         cmdline = [util.shellquote(arg) for arg in cmdline]
         cmdline += ['<', util.nulldev]
         cmdline = ' '.join(cmdline)
         self.ui.debug(cmdline, '\n')
+        return cmdline
 
+    def _run(self, cmd, *args, **kwargs):
+        cmdline = self._cmdline(cmd, *args, **kwargs)
         self.prerun()
         try:
             return util.popen(cmdline)
         finally:
             self.postrun()
 
     def run(self, cmd, *args, **kwargs):
         fp = self._run(cmd, *args, **kwargs)
         output = fp.read()
         self.ui.debug(output)
         return output, fp.close()
 
     def checkexit(self, status, output=''):
         if status:
             if output:
                 self.ui.warn(_('%s error:\n') % self.command)
                 self.ui.warn(output)
             msg = util.explain_exit(status)[0]
             raise util.Abort(_('%s %s') % (self.command, msg))
 
     def run0(self, cmd, *args, **kwargs):
         output, status = self.run(cmd, *args, **kwargs)
         self.checkexit(status, output)
         return output
 
+    def getargmax(self):
+        if '_argmax' in self.__dict__:
+            return self._argmax
+
+        # POSIX requires at least 4096 bytes for ARG_MAX
+        self._argmax = 4096
+        try:
+            self._argmax = os.sysconf("SC_ARG_MAX")
+        except:
+            pass
+
+        # Windows shells impose their own limits on command line length,
+        # down to 2047 bytes for cmd.exe under Windows NT/2k and 2500 bytes
+        # for older 4nt.exe. See http://support.microsoft.com/kb/830473 for
+        # details about cmd.exe limitations.
+
+        # Since ARG_MAX is for command line _and_ environment, lower our limit
+        # (and make happy Windows shells while doing this).
+
+        self._argmax = self._argmax/2 - 1
+        return self._argmax
+
+    def limit_arglist(self, arglist, cmd, *args, **kwargs):
+        limit = self.getargmax() - len(self._cmdline(cmd, *args, **kwargs))
+        bytes = 0
+        fl = []
+        for fn in arglist:
+            b = len(fn) + 3
+            if bytes + b < limit or len(fl) == 0:
+                fl.append(fn)
+                bytes += b
+            else:
+                yield fl
+                fl = [fn]
+                bytes = b
+        if fl:
+            yield fl
+
+    def xargs(self, arglist, cmd, *args, **kwargs):
+        for l in self.limit_arglist(arglist, cmd, *args, **kwargs):
+            self.run0(cmd, *(list(args) + l), **kwargs)
 
 class mapfile(dict):
     def __init__(self, ui, path):
         super(mapfile, self).__init__()
         self.ui = ui
         self.path = path
         self.fp = None
         self.order = []
         self._read()
 
     def _read(self):
         try:
             fp = open(self.path, 'r')
         except IOError, err:
             if err.errno != errno.ENOENT:
                 raise
             return
         for line in fp:
             key, value = line[:-1].split(' ', 1)
             if key not in self:
                 self.order.append(key)
             super(mapfile, self).__setitem__(key, value)
         fp.close()
 
     def __setitem__(self, key, value):
         if self.fp is None:
             try:
                 self.fp = open(self.path, 'a')
             except IOError, err:
                 raise util.Abort(_('could not open map file %r: %s') %
                                  (self.path, err.strerror))
         self.fp.write('%s %s\n' % (key, value))
         self.fp.flush()
         super(mapfile, self).__setitem__(key, value)
 
     def close(self):
         if self.fp:
             self.fp.close()
             self.fp = None

hgext/convert/subversion.py

@@ -1,952 +1,926
 # Subversion 1.4/1.5 Python API backend
 #
 # Copyright(C) 2007 Daniel Holth et al
 #
 # Configuration options:
 #
 # convert.svn.trunk
 #   Relative path to the trunk (default: "trunk")
 # convert.svn.branches
 #   Relative path to tree of branches (default: "branches")
 # convert.svn.tags
 #   Relative path to tree of tags (default: "tags")
 #
 # Set these in a hgrc, or on the command line as follows:
 #
 #   hg convert --config convert.svn.trunk=wackoname [...]
 
 import locale
 import os
 import re
 import sys
 import cPickle as pickle
 import tempfile
 
 from mercurial import strutil, util
 from mercurial.i18n import _
 
 # Subversion stuff. Works best with very recent Python SVN bindings
 # e.g. SVN 1.5 or backports. Thanks to the bzr folks for enhancing
 # these bindings.
 
 from cStringIO import StringIO
 
 from common import NoRepo, commit, converter_source, encodeargs, decodeargs
 from common import commandline, converter_sink, mapfile
 
 try:
     from svn.core import SubversionException, Pool
     import svn
     import svn.client
     import svn.core
     import svn.ra
     import svn.delta
     import transport
 except ImportError:
     pass
 
 def geturl(path):
     try:
         return svn.client.url_from_path(svn.core.svn_path_canonicalize(path))
     except SubversionException:
         pass
     if os.path.isdir(path):
         path = os.path.normpath(os.path.abspath(path))
         if os.name == 'nt':
             path = '/' + path.replace('\\', '/')
         return 'file://%s' % path
     return path
 
 def optrev(number):
     optrev = svn.core.svn_opt_revision_t()
     optrev.kind = svn.core.svn_opt_revision_number
     optrev.value.number = number
     return optrev
 
 class changedpath(object):
     def __init__(self, p):
         self.copyfrom_path = p.copyfrom_path
         self.copyfrom_rev = p.copyfrom_rev
         self.action = p.action
 
 def get_log_child(fp, url, paths, start, end, limit=0, discover_changed_paths=True,
                     strict_node_history=False):
     protocol = -1
     def receiver(orig_paths, revnum, author, date, message, pool):
         if orig_paths is not None:
             for k, v in orig_paths.iteritems():
                 orig_paths[k] = changedpath(v)
         pickle.dump((orig_paths, revnum, author, date, message),
                     fp, protocol)
 
     try:
         # Use an ra of our own so that our parent can consume
         # our results without confusing the server.
         t = transport.SvnRaTransport(url=url)
         svn.ra.get_log(t.ra, paths, start, end, limit,
                        discover_changed_paths,
                        strict_node_history,
                        receiver)
     except SubversionException, (inst, num):
         pickle.dump(num, fp, protocol)
     else:
         pickle.dump(None, fp, protocol)
     fp.close()
 
 def debugsvnlog(ui, **opts):
     """Fetch SVN log in a subprocess and channel them back to parent to
     avoid memory collection issues.
     """
     util.set_binary(sys.stdin)
     util.set_binary(sys.stdout)
     args = decodeargs(sys.stdin.read())
     get_log_child(sys.stdout, *args)
 
 # SVN conversion code stolen from bzr-svn and tailor
 class svn_source(converter_source):
     def __init__(self, ui, url, rev=None):
         super(svn_source, self).__init__(ui, url, rev=rev)
 
         try:
             SubversionException
         except NameError:
             raise NoRepo('Subversion python bindings could not be loaded')
 
         self.encoding = locale.getpreferredencoding()
         self.lastrevs = {}
 
         latest = None
         try:
             # Support file://path@rev syntax. Useful e.g. to convert
             # deleted branches.
             at = url.rfind('@')
             if at >= 0:
                 latest = int(url[at+1:])
                 url = url[:at]
         except ValueError, e:
             pass
         self.url = geturl(url)
         self.encoding = 'UTF-8' # Subversion is always nominal UTF-8
         try:
             self.transport = transport.SvnRaTransport(url=self.url)
             self.ra = self.transport.ra
             self.ctx = self.transport.client
             self.base = svn.ra.get_repos_root(self.ra)
             self.module = self.url[len(self.base):]
             self.modulemap = {} # revision, module
             self.commits = {}
             self.paths = {}
             self.uuid = svn.ra.get_uuid(self.ra).decode(self.encoding)
         except SubversionException, e:
             ui.print_exc()
             raise NoRepo("%s does not look like a Subversion repo" % self.url)
 
         if rev:
             try:
                 latest = int(rev)
             except ValueError:
                 raise util.Abort('svn: revision %s is not an integer' % rev)
 
         try:
             self.get_blacklist()
         except IOError, e:
             pass
 
         self.last_changed = self.latest(self.module, latest)
 
         self.head = self.revid(self.last_changed)
         self._changescache = None
 
         if os.path.exists(os.path.join(url, '.svn/entries')):
             self.wc = url
         else:
             self.wc = None
         self.convertfp = None
 
     def setrevmap(self, revmap):
         lastrevs = {}
         for revid in revmap.iterkeys():
             uuid, module, revnum = self.revsplit(revid)
             lastrevnum = lastrevs.setdefault(module, revnum)
             if revnum > lastrevnum:
                 lastrevs[module] = revnum
         self.lastrevs = lastrevs
 
     def exists(self, path, optrev):
         try:
             svn.client.ls(self.url.rstrip('/') + '/' + path,
                                  optrev, False, self.ctx)
             return True
         except SubversionException, err:
             return False
 
     def getheads(self):
         # detect standard /branches, /tags, /trunk layout
         rev = optrev(self.last_changed)
         rpath = self.url.strip('/')
         cfgtrunk = self.ui.config('convert', 'svn.trunk')
         cfgbranches = self.ui.config('convert', 'svn.branches')
         cfgtags = self.ui.config('convert', 'svn.tags')
         trunk = (cfgtrunk or 'trunk').strip('/')
         branches = (cfgbranches or 'branches').strip('/')
         tags = (cfgtags or 'tags').strip('/')
         if self.exists(trunk, rev) and self.exists(branches, rev) and self.exists(tags, rev):
             self.ui.note('found trunk at %r, branches at %r and tags at %r\n' %
                          (trunk, branches, tags))
             oldmodule = self.module
             self.module += '/' + trunk
             lt = self.latest(self.module, self.last_changed)
             self.head = self.revid(lt)
             self.heads = [self.head]
             branchnames = svn.client.ls(rpath + '/' + branches, rev, False,
                                         self.ctx)
             for branch in branchnames.keys():
                 if oldmodule:
                     module = oldmodule + '/' + branches + '/' + branch
                 else:
                     module = '/' + branches + '/' + branch
                 brevnum = self.latest(module, self.last_changed)
                 brev = self.revid(brevnum, module)
                 self.ui.note('found branch %s at %d\n' % (branch, brevnum))
                 self.heads.append(brev)
 
             if oldmodule:
                 self.tags = '%s/%s' % (oldmodule, tags)
             else:
                 self.tags = '/%s' % tags
 
         elif cfgtrunk or cfgbranches or cfgtags:
             raise util.Abort('trunk/branch/tags layout expected, but not found')
         else:
             self.ui.note('working with one branch\n')
             self.heads = [self.head]
             self.tags  = tags
         return self.heads
 
     def getfile(self, file, rev):
         data, mode = self._getfile(file, rev)
         self.modecache[(file, rev)] = mode
         return data
 
     def getmode(self, file, rev):
         return self.modecache[(file, rev)]
 
     def getchanges(self, rev):
         if self._changescache and self._changescache[0] == rev:
             return self._changescache[1]
         self._changescache = None
         self.modecache = {}
         (paths, parents) = self.paths[rev]
         files, copies = self.expandpaths(rev, paths, parents)
         files.sort()
         files = zip(files, [rev] * len(files))
 
         # caller caches the result, so free it here to release memory
         del self.paths[rev]
         return (files, copies)
 
     def getchangedfiles(self, rev, i):
         changes = self.getchanges(rev)
         self._changescache = (rev, changes)
         return [f[0] for f in changes[0]]
 
     def getcommit(self, rev):
         if rev not in self.commits:
             uuid, module, revnum = self.revsplit(rev)
             self.module = module
             self.reparent(module)
             stop = self.lastrevs.get(module, 0)
             self._fetch_revisions(from_revnum=revnum, to_revnum=stop)
         commit = self.commits[rev]
         # caller caches the result, so free it here to release memory
         del self.commits[rev]
         return commit
 
     def get_log(self, paths, start, end, limit=0, discover_changed_paths=True,
                 strict_node_history=False):
 
         def parent(fp):
             while True:
                 entry = pickle.load(fp)
                 try:
                     orig_paths, revnum, author, date, message = entry
                 except:
                     if entry is None:
                         break
                     raise SubversionException("child raised exception", entry)
                 yield entry
 
         args = [self.url, paths, start, end, limit, discover_changed_paths,
                 strict_node_history]
         arg = encodeargs(args)
         hgexe = util.hgexecutable()
         cmd = '%s debugsvnlog' % util.shellquote(hgexe)
         stdin, stdout = os.popen2(cmd, 'b')
 
         stdin.write(arg)
         stdin.close()
 
         for p in parent(stdout):
             yield p
 
     def gettags(self):
         tags = {}
         start = self.revnum(self.head)
         try:
             for entry in self.get_log([self.tags], 0, start):
                 orig_paths, revnum, author, date, message = entry
                 for path in orig_paths:
                     if not path.startswith(self.tags+'/'):
                         continue
                     ent = orig_paths[path]
                     source = ent.copyfrom_path
                     rev = ent.copyfrom_rev
                     tag = path.split('/')[-1]
                     tags[tag] = self.revid(rev, module=source)
         except SubversionException, (inst, num):
             self.ui.note('no tags found at revision %d\n' % start)
         return tags
 
     def converted(self, rev, destrev):
         if not self.wc:
             return
         if self.convertfp is None:
             self.convertfp = open(os.path.join(self.wc, '.svn', 'hg-shamap'),
                                   'a')
         self.convertfp.write('%s %d\n' % (destrev, self.revnum(rev)))
         self.convertfp.flush()
 
     # -- helper functions --
 
     def revid(self, revnum, module=None):
         if not module:
             module = self.module
         return u"svn:%s%s@%s" % (self.uuid, module.decode(self.encoding),
                                  revnum)
 
     def revnum(self, rev):
         return int(rev.split('@')[-1])
 
     def revsplit(self, rev):
         url, revnum = rev.encode(self.encoding).split('@', 1)
         revnum = int(revnum)
         parts = url.split('/', 1)
         uuid = parts.pop(0)[4:]
         mod = ''
         if parts:
             mod = '/' + parts[0]
         return uuid, mod, revnum
 
     def latest(self, path, stop=0):
         'find the latest revision affecting path, up to stop'
         if not stop:
             stop = svn.ra.get_latest_revnum(self.ra)
         try:
             self.reparent('')
             dirent = svn.ra.stat(self.ra, path.strip('/'), stop)
             self.reparent(self.module)
         except SubversionException:
             dirent = None
         if not dirent:
             raise util.Abort('%s not found up to revision %d' % (path, stop))
 
         return dirent.created_rev
 
     def get_blacklist(self):
         """Avoid certain revision numbers.
         It is not uncommon for two nearby revisions to cancel each other
         out, e.g. 'I copied trunk into a subdirectory of itself instead
         of making a branch'. The converted repository is significantly
         smaller if we ignore such revisions."""
         self.blacklist = util.set()
         blacklist = self.blacklist
         for line in file("blacklist.txt", "r"):
             if not line.startswith("#"):
                 try:
                     svn_rev = int(line.strip())
                     blacklist.add(svn_rev)
                 except ValueError, e:
                     pass # not an integer or a comment
 
     def is_blacklisted(self, svn_rev):
         return svn_rev in self.blacklist
 
     def reparent(self, module):
         svn_url = self.base + module
         self.ui.debug("reparent to %s\n" % svn_url.encode(self.encoding))
         svn.ra.reparent(self.ra, svn_url.encode(self.encoding))
 
     def expandpaths(self, rev, paths, parents):
         def get_entry_from_path(path, module=self.module):
             # Given the repository url of this wc, say
             #   "http://server/plone/CMFPlone/branches/Plone-2_0-branch"
             # extract the "entry" portion (a relative path) from what
             # svn log --xml says, ie
             #   "/CMFPlone/branches/Plone-2_0-branch/tests/PloneTestCase.py"
             # that is to say "tests/PloneTestCase.py"
             if path.startswith(module):
                 relative = path[len(module):]
                 if relative.startswith('/'):
                     return relative[1:]
                 else:
                     return relative
 
             # The path is outside our tracked tree...
             self.ui.debug('%r is not under %r, ignoring\n' % (path, module))
             return None
 
         entries = []
         copyfrom = {} # Map of entrypath, revision for finding source of deleted revisions.
         copies = {}
         revnum = self.revnum(rev)
 
         if revnum in self.modulemap:
             new_module = self.modulemap[revnum]
             if new_module != self.module:
                 self.module = new_module
                 self.reparent(self.module)
 
         for path, ent in paths:
             entrypath = get_entry_from_path(path, module=self.module)
             entry = entrypath.decode(self.encoding)
 
             kind = svn.ra.check_path(self.ra, entrypath, revnum)
             if kind == svn.core.svn_node_file:
                 if ent.copyfrom_path:
                     copyfrom_path = get_entry_from_path(ent.copyfrom_path)
                     if copyfrom_path:
                         self.ui.debug("Copied to %s from %s@%s\n" % (entry, copyfrom_path, ent.copyfrom_rev))
                         # It's probably important for hg that the source
                         # exists in the revision's parent, not just the
                         # ent.copyfrom_rev
                         fromkind = svn.ra.check_path(self.ra, copyfrom_path, ent.copyfrom_rev)
                         if fromkind != 0:
                             copies[self.recode(entry)] = self.recode(copyfrom_path)
                 entries.append(self.recode(entry))
             elif kind == 0: # gone, but had better be a deleted *file*
                 self.ui.debug("gone from %s\n" % ent.copyfrom_rev)
 
                 # if a branch is created but entries are removed in the same
                 # changeset, get the right fromrev
                 if parents:
                     uuid, old_module, fromrev = self.revsplit(parents[0])
                 else:
                     fromrev = revnum - 1
                     # might always need to be revnum - 1 in these 3 lines?
                     old_module = self.modulemap.get(fromrev, self.module)
 
                 basepath = old_module + "/" + get_entry_from_path(path, module=self.module)
                 entrypath = old_module + "/" + get_entry_from_path(path, module=self.module)
 
                 def lookup_parts(p):
                     rc = None
                     parts = p.split("/")
                     for i in range(len(parts)):
                         part = "/".join(parts[:i])
                         info = part, copyfrom.get(part, None)
                         if info[1] is not None:
                             self.ui.debug("Found parent directory %s\n" % info[1])
                             rc = info
                     return rc
 
                 self.ui.debug("base, entry %s %s\n" % (basepath, entrypath))
 
                 frompath, froment = lookup_parts(entrypath) or (None, revnum - 1)
 
                 # need to remove fragment from lookup_parts and replace with copyfrom_path
                 if frompath is not None:
                     self.ui.debug("munge-o-matic\n")
                     self.ui.debug(entrypath + '\n')
                     self.ui.debug(entrypath[len(frompath):] + '\n')
                     entrypath = froment.copyfrom_path + entrypath[len(frompath):]
                     fromrev = froment.copyfrom_rev
                     self.ui.debug("Info: %s %s %s %s\n" % (frompath, froment, ent, entrypath))
 
                 fromkind = svn.ra.check_path(self.ra, entrypath, fromrev)
                 if fromkind == svn.core.svn_node_file:   # a deleted file
                     entries.append(self.recode(entry))
                 elif fromkind == svn.core.svn_node_dir:
                     # print "Deleted/moved non-file:", revnum, path, ent
                     # children = self._find_children(path, revnum - 1)
                     # print "find children %s@%d from %d action %s" % (path, revnum, ent.copyfrom_rev, ent.action)
                     # Sometimes this is tricky. For example: in
                     # The Subversion Repository revision 6940 a dir
                     # was copied and one of its files was deleted
                     # from the new location in the same commit. This
                     # code can't deal with that yet.
                     if ent.action == 'C':
                         children = self._find_children(path, fromrev)
                     else:
                         oroot = entrypath.strip('/')
                         nroot = path.strip('/')
                         children = self._find_children(oroot, fromrev)
                         children = [s.replace(oroot,nroot) for s in children]
                     # Mark all [files, not directories] as deleted.
                     for child in children:
                         # Can we move a child directory and its
                         # parent in the same commit? (probably can). Could
                         # cause problems if instead of revnum -1,
                         # we have to look in (copyfrom_path, revnum - 1)
                         entrypath = get_entry_from_path("/" + child, module=old_module)
                         if entrypath:
                             entry = self.recode(entrypath.decode(self.encoding))
                             if entry in copies:
                                 # deleted file within a copy
                                 del copies[entry]
                             else:
                                 entries.append(entry)
                 else:
                     self.ui.debug('unknown path in revision %d: %s\n' % \
                                   (revnum, path))
             elif kind == svn.core.svn_node_dir:
                 # Should probably synthesize normal file entries
                 # and handle as above to clean up copy/rename handling.
 
                 # If the directory just had a prop change,
                 # then we shouldn't need to look for its children.
                 # Also this could create duplicate entries. Not sure
                 # whether this will matter. Maybe should make entries a set.
                 # print "Changed directory", revnum, path, ent.action, ent.copyfrom_path, ent.copyfrom_rev
                 # This will fail if a directory was copied
                 # from another branch and then some of its files
                 # were deleted in the same transaction.
                 children = self._find_children(path, revnum)
                 children.sort()
                 for child in children:
                     # Can we move a child directory and its
                     # parent in the same commit? (probably can). Could
                     # cause problems if instead of revnum -1,
                     # we have to look in (copyfrom_path, revnum - 1)
                     entrypath = get_entry_from_path("/" + child, module=self.module)
                     # print child, self.module, entrypath
                     if entrypath:
                         # Need to filter out directories here...
                         kind = svn.ra.check_path(self.ra, entrypath, revnum)
                         if kind != svn.core.svn_node_dir:
                             entries.append(self.recode(entrypath))
 
                 # Copies here (must copy all from source)
                 # Probably not a real problem for us if
                 # source does not exist
 
                 # Can do this with the copy command "hg copy"
                 # if ent.copyfrom_path:
                 #     copyfrom_entry = get_entry_from_path(ent.copyfrom_path.decode(self.encoding),
                 #             module=self.module)
                 #     copyto_entry = entrypath
                 #
                 #     print "copy directory", copyfrom_entry, 'to', copyto_entry
                 #
                 #     copies.append((copyfrom_entry, copyto_entry))
 
                 if ent.copyfrom_path:
                     copyfrom_path = ent.copyfrom_path.decode(self.encoding)
                     copyfrom_entry = get_entry_from_path(copyfrom_path, module=self.module)
                     if copyfrom_entry:
                         copyfrom[path] = ent
                         self.ui.debug("mark %s came from %s\n" % (path, copyfrom[path]))
 
                         # Good, /probably/ a regular copy. Really should check
                         # to see whether the parent revision actually contains
                         # the directory in question.
                         children = self._find_children(self.recode(copyfrom_path), ent.copyfrom_rev)
                         children.sort()
                         for child in children:
                             entrypath = get_entry_from_path("/" + child, module=self.module)
                             if entrypath:
                                 entry = entrypath.decode(self.encoding)
                                 # print "COPY COPY From", copyfrom_entry, entry
                                 copyto_path = path + entry[len(copyfrom_entry):]
                                 copyto_entry =  get_entry_from_path(copyto_path, module=self.module)
                                 # print "COPY", entry, "COPY To", copyto_entry
                                 copies[self.recode(copyto_entry)] = self.recode(entry)
                                 # copy from quux splort/quuxfile
 
         return (entries, copies)
 
     def _fetch_revisions(self, from_revnum = 0, to_revnum = 347):
         self.child_cset = None
         def parselogentry(orig_paths, revnum, author, date, message):
             self.ui.debug("parsing revision %d (%d changes)\n" %
                           (revnum, len(orig_paths)))
 
             if revnum in self.modulemap:
                 new_module = self.modulemap[revnum]
                 if new_module != self.module:
                     self.module = new_module
                     self.reparent(self.module)
 
             rev = self.revid(revnum)
             # branch log might return entries for a parent we already have
             if (rev in self.commits or
                 (revnum < self.lastrevs.get(self.module, 0))):
                 return
 
             parents = []
             # check whether this revision is the start of a branch
             if self.module in orig_paths:
                 ent = orig_paths[self.module]
                 if ent.copyfrom_path:
                     # ent.copyfrom_rev may not be the actual last revision
                     prev = self.latest(ent.copyfrom_path, ent.copyfrom_rev)
                     self.modulemap[prev] = ent.copyfrom_path
                     parents = [self.revid(prev, ent.copyfrom_path)]
                     self.ui.note('found parent of branch %s at %d: %s\n' % \
                                      (self.module, prev, ent.copyfrom_path))
                 else:
                     self.ui.debug("No copyfrom path, don't know what to do.\n")
 
             self.modulemap[revnum] = self.module # track backwards in time
 
             orig_paths = orig_paths.items()
             orig_paths.sort()
             paths = []
             # filter out unrelated paths
             for path, ent in orig_paths:
                 if not path.startswith(self.module):
                     self.ui.debug("boring@%s: %s\n" % (revnum, path))
                     continue
                 paths.append((path, ent))
 
             self.paths[rev] = (paths, parents)
 
             # Example SVN datetime. Includes microseconds.
             # ISO-8601 conformant
             # '2007-01-04T17:35:00.902377Z'
             date = util.parsedate(date[:19] + " UTC", ["%Y-%m-%dT%H:%M:%S"])
 
             log = message and self.recode(message)
             author = author and self.recode(author) or ''
             try:
                 branch = self.module.split("/")[-1]
                 if branch == 'trunk':
                     branch = ''
             except IndexError:
                 branch = None
 
             cset = commit(author=author,
                           date=util.datestr(date),
                           desc=log,
                           parents=parents,
                           branch=branch,
                           rev=rev.encode('utf-8'))
 
             self.commits[rev] = cset
             if self.child_cset and not self.child_cset.parents:
                 self.child_cset.parents = [rev]
             self.child_cset = cset
 
         self.ui.note('fetching revision log for "%s" from %d to %d\n' %
                      (self.module, from_revnum, to_revnum))
 
         try:
             for entry in self.get_log([self.module], from_revnum, to_revnum):
                 orig_paths, revnum, author, date, message = entry
                 if self.is_blacklisted(revnum):
                     self.ui.note('skipping blacklisted revision %d\n' % revnum)
                     continue
                 if orig_paths is None:
                     self.ui.debug('revision %d has no entries\n' % revnum)
                     continue
                 parselogentry(orig_paths, revnum, author, date, message)
         except SubversionException, (inst, num):
             if num == svn.core.SVN_ERR_FS_NO_SUCH_REVISION:
                 raise NoSuchRevision(branch=self,
                     revision="Revision number %d" % to_revnum)
             raise
 
     def _getfile(self, file, rev):
         io = StringIO()
         # TODO: ra.get_file transmits the whole file instead of diffs.
         mode = ''
         try:
             revnum = self.revnum(rev)
             if self.module != self.modulemap[revnum]:
                 self.module = self.modulemap[revnum]
                 self.reparent(self.module)
             info = svn.ra.get_file(self.ra, file, revnum, io)
             if isinstance(info, list):
                 info = info[-1]
             mode = ("svn:executable" in info) and 'x' or ''
             mode = ("svn:special" in info) and 'l' or mode
         except SubversionException, e:
             notfound = (svn.core.SVN_ERR_FS_NOT_FOUND,
                 svn.core.SVN_ERR_RA_DAV_PATH_NOT_FOUND)
             if e.apr_err in notfound: # File not found
                 raise IOError()
             raise
         data = io.getvalue()
         if mode == 'l':
             link_prefix = "link "
             if data.startswith(link_prefix):
                 data = data[len(link_prefix):]
         return data, mode
 
     def _find_children(self, path, revnum):
         path = path.strip('/')
         pool = Pool()
         rpath = '/'.join([self.base, path]).strip('/')
         return ['%s/%s' % (path, x) for x in svn.client.ls(rpath, optrev(revnum), True, self.ctx, pool).keys()]
 
 pre_revprop_change = '''#!/bin/sh
 
 REPOS="$1"
 REV="$2"
 USER="$3"
 PROPNAME="$4"
 ACTION="$5"
 
 if [ "$ACTION" = "M" -a "$PROPNAME" = "svn:log" ]; then exit 0; fi
 if [ "$ACTION" = "A" -a "$PROPNAME" = "hg:convert-branch" ]; then exit 0; fi
 if [ "$ACTION" = "A" -a "$PROPNAME" = "hg:convert-rev" ]; then exit 0; fi
 
 echo "Changing prohibited revision property" >&2
 exit 1
 '''
 
 class svn_sink(converter_sink, commandline):
     commit_re = re.compile(r'Committed revision (\d+).', re.M)
 
-    # iterates sublist of given list for concatenated length is within limit
-    def limit_arglist(self, files):
-        if os.name != 'nt':
-            yield files
-            return
-        # When I tested on WinXP, limit = 2500 is NG, 2400 is OK
-        limit = 2000
-        bytes = 0
-        fl = []
-        for fn in files:
-            b = len(fn) + 1
-            if bytes + b < limit:
-                fl.append(fn)
-                bytes += b
-            else:
-                yield fl
-                fl = [fn]
-                bytes = b
-        if fl:
-            yield fl
-
     def prerun(self):
         if self.wc:
             os.chdir(self.wc)
 
     def postrun(self):
         if self.wc:
             os.chdir(self.cwd)
 
     def join(self, name):
         return os.path.join(self.wc, '.svn', name)
 
     def revmapfile(self):
         return self.join('hg-shamap')
 
     def authorfile(self):
         return self.join('hg-authormap')
 
     def __init__(self, ui, path):
         converter_sink.__init__(self, ui, path)
         commandline.__init__(self, ui, 'svn')
         self.delete = []
         self.setexec = []
         self.delexec = []
         self.copies = []
         self.wc = None
         self.cwd = os.getcwd()
 
         path = os.path.realpath(path)
 
         created = False
         if os.path.isfile(os.path.join(path, '.svn', 'entries')):
             self.wc = path
             self.run0('update')
         else:
             wcpath = os.path.join(os.getcwd(), os.path.basename(path) + '-wc')
 
             if os.path.isdir(os.path.dirname(path)):
                 if not os.path.exists(os.path.join(path, 'db', 'fs-type')):
                     ui.status(_('initializing svn repo %r\n') %
                               os.path.basename(path))
                     commandline(ui, 'svnadmin').run0('create', path)
                     created = path
                 path = path.replace('\\', '/')
                 if not path.startswith('/'):
                     path = '/' + path
                 path = 'file://' + path
 
             ui.status(_('initializing svn wc %r\n') % os.path.basename(wcpath))
             self.run0('checkout', path, wcpath)
 
             self.wc = wcpath
         self.opener = util.opener(self.wc)
         self.wopener = util.opener(self.wc)
         self.childmap = mapfile(ui, self.join('hg-childmap'))
         self.is_exec = util.checkexec(self.wc) and util.is_exec or None
 
         if created:
             hook = os.path.join(created, 'hooks', 'pre-revprop-change')
             fp = open(hook, 'w')
             fp.write(pre_revprop_change)
             fp.close()
             util.set_flags(hook, "x")
 
         xport = transport.SvnRaTransport(url=geturl(path))
         self.uuid = svn.ra.get_uuid(xport.ra)
 
     def wjoin(self, *names):
         return os.path.join(self.wc, *names)
 
     def putfile(self, filename, flags, data):
         if 'l' in flags:
             self.wopener.symlink(data, filename)
         else:
             try:
                 if os.path.islink(self.wjoin(filename)):
                     os.unlink(filename)
             except OSError:
                 pass
             self.wopener(filename, 'w').write(data)
 
             if self.is_exec:
                 was_exec = self.is_exec(self.wjoin(filename))
             else:
                 # On filesystems not supporting execute-bit, there is no way
                 # to know if it is set but asking subversion. Setting it
                 # systematically is just as expensive and much simpler.
                 was_exec = 'x' not in flags
 
             util.set_flags(self.wjoin(filename), flags)
             if was_exec:
                 if 'x' not in flags:
                     self.delexec.append(filename)
             else:
                 if 'x' in flags:
                     self.setexec.append(filename)
 
     def delfile(self, name):
         self.delete.append(name)
 
     def copyfile(self, source, dest):
         self.copies.append([source, dest])
 
     def _copyfile(self, source, dest):
         # SVN's copy command pukes if the destination file exists, but
         # our copyfile method expects to record a copy that has
         # already occurred.  Cross the semantic gap.
         wdest = self.wjoin(dest)
         exists = os.path.exists(wdest)
         if exists:
             fd, tempname = tempfile.mkstemp(
                 prefix='hg-copy-', dir=os.path.dirname(wdest))
             os.close(fd)
             os.unlink(tempname)
             os.rename(wdest, tempname)
         try:
             self.run0('copy', source, dest)
         finally:
             if exists:
                 try:
                     os.unlink(wdest)
                 except OSError:
                     pass
                 os.rename(tempname, wdest)
 
     def dirs_of(self, files):
         dirs = set()
         for f in files:
             if os.path.isdir(self.wjoin(f)):
                 dirs.add(f)
             for i in strutil.rfindall(f, '/'):
                 dirs.add(f[:i])
         return dirs
 
     def add_dirs(self, files):
         add_dirs = [d for d in self.dirs_of(files)
                     if not os.path.exists(self.wjoin(d, '.svn', 'entries'))]
         if add_dirs:
             add_dirs.sort()
-            for fl in self.limit_arglist(add_dirs):
-                self.run('add', non_recursive=True, quiet=True, *fl)
+            self.xargs(add_dirs, 'add', non_recursive=True, quiet=True)
         return add_dirs
 
     def add_files(self, files):
         if files:
-            for fl in self.limit_arglist(files):
-                self.run('add', quiet=True, *fl)
+            self.xargs(files, 'add', quiet=True)
         return files
 
     def tidy_dirs(self, names):
         dirs = list(self.dirs_of(names))
         dirs.sort(reverse=True)
         deleted = []
         for d in dirs:
             wd = self.wjoin(d)
             if os.listdir(wd) == '.svn':
                 self.run0('delete', d)
                 deleted.append(d)
         return deleted
 
     def addchild(self, parent, child):
         self.childmap[parent] = child
 
     def revid(self, rev):
         return u"svn:%s@%s" % (self.uuid, rev)
 
     def putcommit(self, files, parents, commit):
         for parent in parents:
             try:
                 return self.revid(self.childmap[parent])
             except KeyError:
                 pass
         entries = set(self.delete)
         files = util.frozenset(files)
         entries.update(self.add_dirs(files.difference(entries)))
         if self.copies:
             for s, d in self.copies:
                 self._copyfile(s, d)
             self.copies = []
         if self.delete:
-            for fl in self.limit_arglist(self.delete):
-                self.run0('delete', *fl)
+            self.xargs(self.delete, 'delete')
             self.delete = []
         entries.update(self.add_files(files.difference(entries)))
         entries.update(self.tidy_dirs(entries))
         if self.delexec:
-            for fl in self.limit_arglist(self.delexec):
-                self.run0('propdel', 'svn:executable', *fl)
+            self.xargs(self.delexec, 'propdel', 'svn:executable')
             self.delexec = []
         if self.setexec:
-            for fl in self.limit_arglist(self.setexec):
-                self.run0('propset', 'svn:executable', '*', *fl)
+            self.xargs(self.setexec, 'propset', 'svn:executable', '*')
             self.setexec = []
 
         fd, messagefile = tempfile.mkstemp(prefix='hg-convert-')
         fp = os.fdopen(fd, 'w')
         fp.write(commit.desc)
         fp.close()
         try:
             output = self.run0('commit',
                                username=util.shortuser(commit.author),
                                file=messagefile,
                                encoding='utf-8')
             try:
                 rev = self.commit_re.search(output).group(1)
             except AttributeError:
                 self.ui.warn(_('unexpected svn output:\n'))
                 self.ui.warn(output)
                 raise util.Abort(_('unable to cope with svn output'))
             if commit.rev:
                 self.run('propset', 'hg:convert-rev', commit.rev,
                          revprop=True, revision=rev)
             if commit.branch and commit.branch != 'default':
                 self.run('propset', 'hg:convert-branch', commit.branch,
                          revprop=True, revision=rev)
             for parent in parents:
                 self.addchild(parent, rev)
             return self.revid(rev)
         finally:
             os.unlink(messagefile)
 
     def puttags(self, tags):
         self.ui.warn(_('XXX TAGS NOT IMPLEMENTED YET\n'))