Outline of this patch:
1. Define a new ipdl message called |CloseAfterInvalidationComplete| to trigger the close event after all transactions are complete only if the database is invalidated by the user agent.
2. Make sure the following event sequence is consistent during invalidation according to the steps in |5.2. Closing a database| by the following 2 solutions:
IDBRequest.onerror -> IDBTransaction.onerror -> IDBTransaction.onabort -> IDBDatabase.onclose.
2.1. In parent process, do not force to abort the transactions after invalidation but wait for all the transactions in its child process are complete.
2.2. In child process, make sure that each IDBTransaction will notify its completion to the parent after all its pending IDBRequests are finished.
3. Add test_database_onclose.js to test the close event especially when read/write operation is ongoing.
4. Add test_database_close_without_onclose.js as a XPCShell test because setTimeout() is not preferred in Mochitest to ensure that the IDBDatabase.onclose event won't be sent after closed normally.
The bulk of this commit was generated with a script, executed at the top
level of a typical source code checkout. The only non-machine-generated
part was modifying MFBT's moz.build to reflect the new naming.
CLOSED TREE makes big refactorings like this a piece of cake.
# The main substitution.
find . -name '*.cpp' -o -name '*.cc' -o -name '*.h' -o -name '*.mm' -o -name '*.idl'| \
xargs perl -p -i -e '
s/nsRefPtr\.h/RefPtr\.h/g; # handle includes
s/nsRefPtr ?</RefPtr</g; # handle declarations and variables
'
# Handle a special friend declaration in gfx/layers/AtomicRefCountedWithFinalize.h.
perl -p -i -e 's/::nsRefPtr;/::RefPtr;/' gfx/layers/AtomicRefCountedWithFinalize.h
# Handle nsRefPtr.h itself, a couple places that define constructors
# from nsRefPtr, and code generators specially. We do this here, rather
# than indiscriminantly s/nsRefPtr/RefPtr/, because that would rename
# things like nsRefPtrHashtable.
perl -p -i -e 's/nsRefPtr/RefPtr/g' \
mfbt/nsRefPtr.h \
xpcom/glue/nsCOMPtr.h \
xpcom/base/OwningNonNull.h \
ipc/ipdl/ipdl/lower.py \
ipc/ipdl/ipdl/builtin.py \
dom/bindings/Codegen.py \
python/lldbutils/lldbutils/utils.py
# In our indiscriminate substitution above, we renamed
# nsRefPtrGetterAddRefs, the class behind getter_AddRefs. Fix that up.
find . -name '*.cpp' -o -name '*.h' -o -name '*.idl' | \
xargs perl -p -i -e 's/nsRefPtrGetterAddRefs/RefPtrGetterAddRefs/g'
if [ -d .git ]; then
git mv mfbt/nsRefPtr.h mfbt/RefPtr.h
else
hg mv mfbt/nsRefPtr.h mfbt/RefPtr.h
fi
--HG--
rename : mfbt/nsRefPtr.h => mfbt/RefPtr.h
This is motivated by three separate but related problems:
1. Our concept of recursion depth is broken for things that run from AfterProcessNextEvent observers (e.g. Promises). We decrement the recursionDepth counter before firing observers, so a Promise callback running at the lowest event loop depth has a recursion depth of 0 (whereas a regular nsIRunnable would be 1). This is a problem because it's impossible to distinguish a Promise running after a sync XHR's onreadystatechange handler from a top-level event (since the former runs with depth 2 - 1 = 1, and the latter runs with just 1).
2. The nsIThreadObserver mechanism that is used by a lot of code to run "after" the current event is a poor fit for anything that runs script. First, the order the observers fire in is the order they were added, not anything fixed by spec. Additionally, running script can cause the event loop to spin, which is a big source of pain here (bholley has some nasty bug caused by this).
3. We run Promises from different points in the code for workers and main thread. The latter runs from XPConnect's nsIThreadObserver callbacks, while the former runs from a hardcoded call to run Promises in the worker event loop. What workers do is particularly problematic because it means we can't get the right recursion depth no matter what we do to nsThread.
The solve this, this patch does the following:
1. Consolidate some handling of microtasks and all handling of stable state from appshell and WorkerPrivate into CycleCollectedJSRuntime.
2. Make the recursionDepth counter only available to CycleCollectedJSRuntime (and its consumers) and remove it from the nsIThreadInternal and nsIThreadObserver APIs.
3. Adjust the recursionDepth counter so that microtasks run with the recursionDepth of the task they are associated with.
4. Introduce the concept of metastable state to replace appshell's RunBeforeNextEvent. Metastable state is reached after every microtask or task is completed. This provides the semantics that bent and I want for IndexedDB, where transactions autocommit at the end of a microtask and do not "spill" from one microtask into a subsequent microtask. This differs from appshell's RunBeforeNextEvent in two ways:
a) It fires between microtasks, which was the motivation for starting this.
b) It no longer ensures that we're at the same event loop depth in the native event queue. bent decided we don't care about this.
5. Reorder stable state to happen after microtasks such as Promises, per HTML. Right now we call the regular thread observers, including appshell, before the main thread observer (XPConnect), so stable state tasks happen before microtasks.
The bulk of this commit was generated by running:
run-clang-tidy.py \
-checks='-*,llvm-namespace-comment' \
-header-filter=^/.../mozilla-central/.* \
-fix
This patch was mostly generated with the following command:
find . -name "*.h" -o -name "*.cpp" | xargs sed -e '/WrapObject(JSContext/ {; N; s/\(WrapObject(JSContext *\* *a\{0,1\}[Cc]x\),\n\{0,1\} *JS::Handle<JSObject\*> a\{0,1\}[sS]cope/\1/ ; }' -i ""
and then reverting the changes that made to
dom/bindings/BindingUtils.h, since those WrapObject methods are not
the ones we're trying to change here, plus a bunch of manual fixups
for cases that this command did not catch (including all the callsites
of WrapObject()).
This patch was mostly generated with this command:
find . -name "*.h" -o -name "*.cpp" | xargs sed -e 's/Binding::Wrap(aCx, aScope, this/Binding::Wrap(aCx, this/' -e 's/Binding_workers::Wrap(aCx, aScope, this/Binding_workers::Wrap(aCx, this/' -e 's/Binding::Wrap(cx, scope, this/Binding::Wrap(cx, this/' -i ""
plus a few manual fixes to dom/bindings/Codegen.py, js/xpconnect/src/event_impl_gen.py, and a few C++ files that were not caught in the search-and-replace above.
