759805 - nsICacheSession::AsyncOpenCacheEntry sometimes returns a failure code even after it has queued a call to the nsICacheListener

Status: RESOLVED WONTFIX

(Core :: Networking: Cache, defect)

Description

[Brian Smith (:briansmith, :bsmith, use NEEDINFO?)]

If nsICacheSession::AsyncOpenCacheEntry is going to eventually call one of the listener's callback methods, then it MUST return rv such that NS_SUCCEEDED(rv). Conversely, if nsICacheSession::AsyncOpenCacheEntry will NOT call one of the listener's callback methods, then it must return rv such that NS_FAILED(rv).

With my patches in bug 722034, I have run into a case where AsyncOpenCacheEntry is returning NS_ERROR_CACHE_KEY_NOT_FOUND in test dom/tests/mochitest/ajax/offline/test_changingManifest.html, and ALSO calling my listener's OnCacheEntryAvailable method.

The code for AsyncOpenCacheEntry is:

    nsresult rv;
    rv = nsCacheService::OpenCacheEntry(this,
                                        key,
                                        accessRequested,
                                        !noWait,
                                        listener,
                                        nsnull); // no result

    if (rv == NS_ERROR_CACHE_WAIT_FOR_VALIDATION) rv = NS_OK;
    return rv;

I guess nsCacheService::OpenCacheEntry has the same problem; it should not be returning a failure status if it has queued a request for the listener, so that the "if (rv == NS_ERROR_CACHE_WAIT_FOR_VALIDATION) rv = NS_OK;" statement is unnecessary.

Comment 1

[Brian Smith (:briansmith, :bsmith, use NEEDINFO?)]

dom/tests/mochitest/ajax/offline/test_overlap.html is another test that triggers this (intermittently?).

Comment 2

[Michal Novotny [:michal]]

old cache bug