diff -r 2f0ea1163b9e -r fd16d9a1234b src/mercurialserver/access.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/mercurialserver/access.py	Fri Mar 06 09:15:00 2009 +0000
@@ -0,0 +1,51 @@
+# Copyright 2008-2009 LShift Ltd
+# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
+#
+# Authors:
+# Paul Crowley <paul@lshift.net>
+# Vadim Gelfer <vadim.gelfer@gmail.com>
+#
+# This software may be used and distributed according to the terms
+# of the GNU General Public License, incorporated herein by reference.
+
+from mercurial.i18n import _
+import mercurial.util
+import mercurial.node
+
+import os
+from mercurialserver import ruleset
+from mercurialserver import changes
+
+class Checker(object):
+    '''acl checker.'''
+
+    def __init__(self, ui, repo):
+        self.ui = ui
+        self.repo = repo
+        
+        self.rules = ruleset.rules_from_env()
+        self.rules.set(user = os.environ['REMOTE_USER'])
+        self.rules.set(repo = os.environ['HG_REPO_PATH'])
+
+    def allow(self, ctx):
+        branch = ctx.branch()
+        if not self.rules.allow("write", branch=branch, file=None):
+            return False
+        for f in ctx.files():
+            if not self.rules.allow("write", branch=branch, file=f):
+                return False
+        return True
+
+    def check(self, ctx):
+        '''return if access allowed, raise exception if not.'''
+        if not self.allow(ctx):
+            raise mercurial.util.Abort(_('%s: access denied for changeset %s') %
+                (__name__, mercurial.node.short(ctx.node())))
+
+def hook(ui, repo, hooktype, node=None, source=None, **kwargs):
+    if hooktype != 'pretxnchangegroup':
+        raise mercurial.util.Abort(_('config error - hook type "%s" cannot stop '
+                           'incoming changesets') % hooktype)
+    c = Checker(ui, repo)
+    for ctx in changes.changes(repo, node):
+        c.check(ctx)