Check protocol versions

This also allows the old unidentified protocol

mercurial/hg.py

@@ -1744,11 +1744,21 b' class httprepository:'
         qs = urllib.urlencode(q)
         cu = "%s?%s" % (self.url, qs)
         resp = urllib2.urlopen(cu)
+        proto = resp.headers['content-type']
 
-        if not resp.headers['content-type'].startswith('application/hg'):
+        # accept old "text/plain" and "application/hg-changegroup" for now
+        if not proto.startswith('application/mercurial') and \
+               not proto.startswith('text/plain') and \
+               not proto.startswith('application/hg-changegroup'):
             raise RepoError("'%s' does not appear to be an hg repository"
                             % self.url)
 
+        if proto.startswith('application/mercurial'):
+            version = proto[22:]
+            if float(version) > 0.1:
+                raise RepoError("'%s' uses newer protocol %s" %
+                                (self.url, version))
+
         return resp
 
     def heads(self):

mercurial/hgweb.py

@@ -670,7 +670,7 b' class hgweb:'
                 sys.stdout.write(" ".join(map(hex, b)) + "\n")
 
         elif args['cmd'][0] == 'between':
-            httphdr("application/hg-0.1")
+            httphdr("application/mercurial-0.1")
             nodes = []
             if args.has_key('pairs'):
                 pairs = [ map(bin, p.split("-"))