In the current code there are 3 main issues:
1. nsFileStream is not really thread-safe. There is nothing to protect the
internal members and we see crashes.
2. nsPipeInputStream doesn't implement ::Seek() method and that caused issues
in devtools when a nsHttpChannel sends POST data using a pipe. In order to fix
this, bug 1494176 added a check in nsHttpChannel: if the stream doesn't
implement ::Seek(), let's clone it. This was an hack around nsPipeInputStream,
and it's bad.
3. When nsHttpChannel sends POST data using a file stream, nsFileStream does
I/O on main-thread because of the issue 2. Plus, ::Seek() is called on the
main-thread causing issue 1.
Note that nsPipeInputStream implements only ::Tell(), of the nsISeekableStream
methods. It doesn't implement ::Seek() and it doesn't implement ::SetEOF().
With this patch I want to fix point 2 and point 3 (and consequentially issue 1
- but we need a separate fix for it - follow up). The patch does:
1. it splits nsISeekableStream in 2 interfaces: nsITellableStream and
nsISeekableStream.
2. nsPipeInputStream implements only nsITellableStream. Doing this, we don't
need the ::Seek() check for point 2 in nsHttpChannel: a simple QI check is
enough.
3. Because we don't call ::Seek() in nsHttpChannel, nsFileStream doesn't do I/O
on the main-thread, and we don't crash doing so.
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
The bulk of this commit was generated by running:
run-clang-tidy.py \
-checks='-*,llvm-namespace-comment' \
-header-filter=^/.../mozilla-central/.* \
-fix
Sylvestre Ledru
Andrea Marchesini
Michal Novotny
Honza Bambas
Nathan Froyd
Birunthan Mohanathas
Ehsan Akhgari
Ed Morley