This does not work: only fixes the object server, but needs the proxy
server doing the same thing, too.
Needs proper logging (for some reason, the intercepted exception
and the supposed 500 do not log ("supposed" because, of course, with
the broken TCP connection 200 logs instead - with full length)).
Needs a succint comment that explains why file.close() is not hooked.

commit 311b158d735b749d5a1624fbd8000c496ca47481
Author: Pete Zaitcev <zaitcev@yahoo.com>
Date:   Thu Mar 15 15:56:07 2012 -0600

    lp:704015 candidate 1

diff --git a/swift/obj/server.py b/swift/obj/server.py
index f631507..f2a4d6a 100644
--- a/swift/obj/server.py
+++ b/swift/obj/server.py
@@ -122,6 +122,7 @@ class DiskFile(object):
         self.iter_etag = None
         self.started_at_0 = False
         self.read_to_eof = False
+        self.expect_to_read = 0
         self.quarantined_dir = None
         self.keep_cache = False
         if not os.path.exists(self.datadir):
@@ -175,10 +176,17 @@ class DiskFile(object):
                     self.read_to_eof = True
                     self.drop_cache(self.fp.fileno(), dropped_cache,
                         read - dropped_cache)
+                    # lp:704015 (could force verify_file, but read is here, so)
+                    if self.expect_to_read != read:
+                        # raise Exception("Unexpected EOF at %d" % read)
+                        raise
                     break
         finally:
             self.close()
 
+    def arm_expectation(self, file_size):
+        self.expect_to_read = file_size
+
     def app_iter_range(self, start, stop):
         """Returns an iterator over the data file for range (start, stop)"""
         if start:
@@ -670,6 +678,7 @@ class ObjectController(object):
            if_modified_since:
             file.close()
             return HTTPNotModified(request=request)
+        file.arm_expectation(file_size)
         response = Response(app_iter=file,
                         request=request, conditional_response=True)
         response.headers['Content-Type'] = file.metadata.get('Content-Type',