Resolved, thanks to Christos via squid-dev. Bug is in the ICAP server implementation, not in Squid. The ICAP server cannot *only* respond with 204s as it must echo the messages when required by the ICAP client, per the RFC. Lisa On Thu, Dec 4, 2008 at 1:06 PM, Lisa Fowler <lisa.fowler@xxxxxxxxx> wrote: > Hello- > > I've searched through the archives and can't find anything pertaining > to this problem, so I hope that someone can help with this. > > I have a Squid 3.0 installation (a build from November) with the ICAP > client running, intercepting responses precache, which then forwards > the entire responses to the ICAP server. I have a simple Python ICAP > server that does nothing but respond to OPTIONS and sends back 204s > otherwise. Preview is not enabled. > > For *most* webpages, this works fine (e.g. http://www.google.com > http://www.mozilla.org), and the webpage is forwarded and all content > is rendered properly on the web client. > > For certain webpages (e.g. http://www.mozillazine.org), the ICAP > server receives the content, responds with the 204 as usual, but then > the client never receives webpage and thus renders a blank page. > > Looking under the hood, Squid deterministically fails in > ICAPModXact::virginContentSize() at the Must(virginConsumed <= start > && start <= end) line. > > I'm deep in the murky waters of debugging, and it seems that there's a > quirk in whether or not virginConsumed is reset to 0, such that I get > a failure on the above Must assertion, for example (36033 <= 0 && 0 <= > 36033) . I wonder if it's related to how > virgin.body_pipe->buf().contentSize() is handled in the case of > virginBodySending, such that in ICAPModXact::echoMore(), sizeMax is 0, > and thus virginBodySending.progress(size) is never called... In the > cases that *do* work, virginBodySending.progress(size) is called, but > not in the cases that fail. The cases that fail have contentSize > zeroed out (because virginBodySending.progress(size) is not called)... > > Any ideas/experience/advice? > > Thanks, > Lisa >
