After adopting the new thread model for safebrowsing, we will create a new
lookup cache for update so we can still check lookup cache at the same time.
Prefix set, completions will be generated when we open the new lookup cache
but it won't include cache, so we will loss cache after that.
This patch will copy cache data from old lookup cache to new lookup
cache while update.
MozReview-Commit-ID: L0WpiHOGIGm
In V2 we shuffled the hash entries before sending the request to obscure the real
entry from noises. We should also hide the real entry in V4. Using sort() is
enough for both V2 and V4 because the array contains exactly 5 entries in almost
all cases.
MozReview-Commit-ID: 4uOXIF83KQL
In this patch, we will make Safebrowsing V2 caching use the same algorithm as V4.
So we remove "mMissCache" for negative caching and TableFresness check for
positive caching.
But Safebrowsing V2 doesn't contain negative/positive cache duration information in
gethash response. So we hard-code a fixed value, 15 minutes, as cache duration.
In this way, we can sync the mechanism we handle caching for V2 and V4.
An extra effort for V2 here is that we need to manually record prefixes misses
because we won't get any response for those prefixes(implemented in
nsUrlClassifierLookupCallback::CacheMisses).
This patch includes following changes:
1. nsUrlClassifierHashCompleter.js
nsUrlClassifierHashCompleter.idl
- Add completionV4 interface for hashCompleter to pass response data to
DB service.
- Process response data includes negative cache duration, matched full
hashes and cache duration for each match. Full matches are passed through
nsIFullHashMatch interface.
- Change _requests.responses from array contains matched fullhashes to
dictionary so that it can store additional information likes negative cache
duration.
2. nsUrlClassifierDBService.cpp
- Implement CompletionV4 interface, store response data to CacheResultV4
object. Expired duration to expired time is handled here.
- Add CacheResultToTableUpdate function to convert V2 & V4 cache result
to TableUpdate object.
3. LookupCache.h
- Extend CacheResult to CacheResultV2 and CacheResultV4 so we can store
response data in CompletionV2 and CompletionV4.
4. HashStore.h
- Add API and member variable in TableUpdateV4 to store response data.
TableUpdate object is used by DB service to pass update data or gethash
response to Classifier, so we need to extend TableUpdateV4 to be able
to store fullHashes.find response.
6. Entry.h
- Define the structure about how we cache fullHashes.find response.
MozReview-Commit-ID: FV4yAl2SAc6
This patch includes following changes:
1. nsUrlClassifierHashCompleter.js
nsUrlClassifierHashCompleter.idl
- Add completionV4 interface for hashCompleter to pass response data to
DB service.
- Process response data includes negative cache duration, matched full
hashes and cache duration for each match. Full matches are passed through
nsIFullHashMatch interface.
- Change _requests.responses from array contains matched fullhashes to
dictionary so that it can store additional information likes negative cache
duration.
2. nsUrlClassifierDBService.cpp
- Implement CompletionV4 interface, store response data to CacheResultV4
object. Expired duration to expired time is handled here.
- Add CacheResultToTableUpdate function to convert V2 & V4 cache result
to TableUpdate object.
3. LookupCache.h
- Extend CacheResult to CacheResultV2 and CacheResultV4 so we can store
response data in CompletionV2 and CompletionV4.
4. HashStore.h
- Add API and member variable in TableUpdateV4 to store response data.
TableUpdate object is used by DB service to pass update data or gethash
response to Classifier, so we need to extend TableUpdateV4 to be able
to store fullHashes.find response.
6. Entry.h
- Define the structure about how we cache fullHashes.find response.
MozReview-Commit-ID: KgR1NASl7GC
A new function Classifier::AsyncApplyUpdates() is implemented for async update.
Besides, all public Classifier interfaces become "worker thread only" and
we remove DBServiceWorker::ApplyUpdatesBackground/Foreground.
In DBServiceWorker::FinishUpdate, instead of calling Classifier::ApplyUpdates,
we call Classifier::AsyncApplyUpdates and install a callback for notifying
the update observer when update is finished. The callback will occur on the
caller thread (i.e. worker thread.)
As for the shutdown issue, when the main thread is notified to shut down,
we at first *synchronously* dispatch an event to the worker thread to
shut down the update thread. After getting synchronized with all other
threads, we send last two events "CancelUpdate" and "CloseDb" to notify
dangling update (i.e. BeginUpdate is called but FinishUpdate isn't)
and do cleanup work.
MozReview-Commit-ID: DXZvA2eFKlc
