hgweb: be sure to drain request data even in early error conditions

Thanks to Mads Kiilerich with noticing this. The hg client can only read data
after all the sent data has been read, so we have to read all the request data
even if we're not going to do anything with it (in error conditions). This
is not easy to fix in the client, because we're using Python's httplib, which
is strictly stateful. Abstracted the draining into a separate method.

mercurial/hgweb/hgweb_mod.py

@@ -91,7 +91,12 b' class hgweb(object):'
         if cmd and cmd in protocol.__all__:
             try:
                 if cmd in perms:
-                    self.check_perm(req, perms[cmd])
+                    try:
+                        self.check_perm(req, perms[cmd])
+                    except ErrorResponse, inst:
+                        if cmd == 'unbundle':
+                            req.drain()
+                        raise
                 method = getattr(protocol, cmd)
                 return method(self.repo, req)
             except ErrorResponse, inst:

mercurial/hgweb/protocol.py

@@ -117,11 +117,7 b' def unbundle(repo, req):'
 
     # fail early if possible
     if not check_heads():
-        length = int(req.env.get('CONTENT_LENGTH', 0))
-        for s in util.filechunkiter(req, limit=length):
-            # drain incoming bundle, else client will not see
-            # response when run outside cgi script
-            pass
+        req.drain()
         raise ErrorResponse(HTTP_OK, 'unsynced changes')
 
     # do not lock repo until all changegroup data is

mercurial/hgweb/request.py

@@ -7,6 +7,7 b''
 # of the GNU General Public License, incorporated herein by reference.
 
 import socket, cgi, errno
+from mercurial import util
 from common import ErrorResponse, statusmessage
 
 shortcuts = {
@@ -57,6 +58,12 b' class wsgirequest(object):'
     def read(self, count=-1):
         return self.inp.read(count)
 
+    def drain(self):
+        '''need to read all data from request, httplib is half-duplex'''
+        length = int(self.env.get('CONTENT_LENGTH', 0))
+        for s in util.filechunkiter(self.inp, limit=length):
+            pass
+
     def respond(self, status, type=None, filename=None, length=0):
         if self._start_response is not None: