Before, we were calling nsDeviceContextSpecGTK::StartPrintJob within the
gtk_enumerate_printers callback function as soon as we found the printer
we wanted to print from. This was causing the GTK printing backend to get
confused about what the capabilities of the selected printer were when running
in the content process, due to https://bugzilla.gnome.org/show_bug.cgi?id=753041.
This moves the call to StartPrintJob to the next tick of the event loop.
The current situation looks like this: Firefox launches the plugin-container
with two environment variables set:
LD_LIBRARY_PATH=$FIREFOX_DIR:$LD_LIBRARY_PATH
LD_PRELOAD=$FIREFOX_DIR/libmozgtk2.so:$LD_PRELOAD
libxul.so has a dependency on libmozgtk.so (without "2"), but libmozgtk2.so
has a SONAME of libmozgtk.so, so ld.so recognizes libmozgtk2.so as a
dependency of libxul.so, and uses it instead of the actual libmozgtk.so,
making the plugin-container use Gtk+2 instead of Gtk+3 to load Gtk+2 plugins.
Now, ASan sets things up in shared libraries such that they needs a symbol
from the executable binary. So in the case of plugin-container, the
plugin-container executable itself contains some ASan symbols such as
__asan_init_v3. libmozgtk2.so, OTOH, contains an undefined weak reference to
that symbol, like all other Firefox shared libraries.
Since libmozgtk2.so is LD_PRELOADed, it is loaded _before_ the
plugin-container executable, and __asan_init_v3 can't be resolved.
Disabling ASan for libmozgtk2.so would be a possibility, but the build system
doesn't really know how to do that, and filtering out -fsanitize=address
can be fragile.
The alternative possibility, implemented here, is to change the library
loading strategy, renaming libmozgtk2.so to gtk2/libmozgtk.so, and setting
the following environment variable when Firefox launches the plugin-container:
LD_LIBRARY_PATH=$FIREFOX_DIR/gtk2:$FIREFOX_DIR:$LD_LIBRARY_PATH
The bulk of this commit was generated by running:
run-clang-tidy.py \
-checks='-*,llvm-namespace-comment' \
-header-filter=^/.../mozilla-central/.* \
-fix
This conversion was done with the script:
find . -name '*.cpp' -o -name '*.h' -o -name '*.mm' -o -name '*.idl' | \
egrep -v 'cairo-win32-refptr.h|RefPtr.h|TestRefPtr.cpp' | \
xargs sed -i -e 's/mozilla::TemporaryRef</already_AddRefed</g' \
-e 's/TemporaryRef</already_AddRefed</g'
Manual fixups were performed in the following instances:
- We handled mfbt/RefPtr.h manually so as to not convert TemporaryRef itself
into already_AddRefed.
- The following files had explicit Move() calls added to make up for the lack
of a copy constructor on already_AddRefed:
dom/base/ImageEncoder.cpp
dom/media/MediaTaskQueue.{h,cpp}
dom/media/webaudio/PannerNode.cpp
- A redundant overload for MediaTaskQueue::Dispatch was deleted.
- A few manual fixups were required in mfbt/tests/TestRefPtr.cpp.
- Comments, using declarations, and forward declarations relating to
TemporaryRef in dom/canvas/ and gfx/layers/ were changed to refer to
already_AddRefed.
