This abstraction will help us to support multiple IPC transport
mechanisms going forward. For now, we only have a TransportSocket that
implements the same behavior we previously had, using Unix Sockets for
IPC.
There is an issue where gifs with many frames cannot be loaded, as each
bitmap is sent over IPC using a separate file descriptor, and there is
limit on the maximum number of descriptors per IPC message. Thus, trying
to load gifs with more than 64 frames (the current limit) causes the
image decoder process to die.
This commit introduces the BitmapSequence class, which is a thin wrapper
around the type Vector<Optional<NonnullRefPtr<Gfx::Bitmap>>> and
provides an IPC encode/decode routine that collates all bitmap data into
a single buffer so that only a single file descriptor is required per
IPC transfer, even if multiple frames are being sent.
Before this change, we were passing them as Gfx::ShareableBitmap. The
problem is that shareable bitmaps keep their underlying file descriptor
open, so that they can be shared again with someone else.
When a Gfx::Bitmap is decoded from an IPC message, the file descriptor
is closed and recovered immediately.
This fixes an issue where we'd accumulate one file descriptor for every
image decoded. This eventually led to descriptor starvation after enough
images were loaded and still referenced at the same time.
This large commit also refactors LibWebView's process handling to use
a top-level Application class that uses a new WebView::Process class to
encapsulate the IPC-centric nature of each helper process.
Most of these now just await the image decoding, equivalent (ish) to
the old behavior. A more async-aware refactor should happen some time
in the future.
ImageDecoder now queues up image decoding requests and returns the
images back to the caller later. ImageDecoderClient has a new
promise-based API that allows callers to attach their own resolve/reject
handlers to the responses from ImageDecoder.
Exif metadata have two tags to store the pixel density along each axis.
If both values are different and no action is taken, the resulting image
will appear deformed. This commit scales the displayed bitmap
accordingly to these tags in order to show the image in its intended
shape. This unfortunately includes a lot of plumbing to get this
information through IPC.
This commit un-deprecates DeprecatedString, and repurposes it as a byte
string.
As the null state has already been removed, there are no other
particularly hairy blockers in repurposing this type as a byte string
(what it _really_ is).
This commit is auto-generated:
$ xs=$(ack -l \bDeprecatedString\b\|deprecated_string AK Userland \
Meta Ports Ladybird Tests Kernel)
$ perl -pie 's/\bDeprecatedString\b/ByteString/g;
s/deprecated_string/byte_string/g' $xs
$ clang-format --style=file -i \
$(git diff --name-only | grep \.cpp\|\.h)
$ gn format $(git ls-files '*.gn' '*.gni')
This patch brings a service to handle image decompression. With it comes
security enhancement due to the process boundary. Indeed, consequences
of a potential attack is reduced as only the decoder will crash without
perturbing the WebContent process.
It also allows us to display pages containing images that we claim to
support but still make us crash, like for not-finished-yet decoders.
As an example, we can now load https://jpegxl.info/jxl-art.html without
crashing the WebContent process.
This library offers tools to communicate with an ImageDecoder server
through IPC. There is currently no such executable for Lagom but that
shouldn't take long :^)
Originally I simply thought that passing file paths is quite OK, but as
Linus pointed to, it turned out that passing file paths to ensure some
files are able to be decoded is awkward because it does not work with
images being served over HTTP.
Therefore, ideally we should just use the MIME type as an optional
argument to ensure that we can always fallback to use that in case
sniffing for the correct image type has failed so we can still detect
files like with the TGA format, which has no magic bytes.
Because TGA images don't have magic bytes as a signature to be detected,
instead assume a sequence of ReadonlyBytes is a possible TGA image only
if we are given a path so we could check the extension of the file and
see if it's a TGA image.
When we know the path of the file being loaded, we will try to first
check its extension, and only if there's no match to a known decoder,
based on simple extension lookup, then we would probe for other formats
as usual with the normal sniffing method.
Otherwise, we end up propagating those dependencies into targets that
link against that library, which creates unnecessary link-time
dependencies.
Also included are changes to readd now missing dependencies to tools
that actually need them.
This commit does three things atomically:
- switch over Core::Account+SystemServer+LoginServer to sid based socket
names.
- change socket names with %uid to %sid.
- add/update necessary pledges and unveils.
Userland: Switch over servers to sid based sockets
Userland: Properly pledge and unveil for sid based sockets
This patch allows to insert "%uid" in `IPC_CLIENT_CONNECTION`
declaration and in SystemServer's ini files. This pattern is replaced
then replaced by the UID of the owner of the service. It opens a path
for seamlessly managed, per-user portal.
This change unfortunately cannot be atomically made without a single
commit changing everything.
Most of the important changes are in LibIPC/Connection.cpp,
LibIPC/ServerConnection.cpp and LibCore/LocalServer.cpp.
The notable changes are:
- IPCCompiler now generates the decode and decode_message functions such
that they take a Core::Stream::LocalSocket instead of the socket fd.
- IPC::Decoder now uses the receive_fd method of LocalSocket instead of
doing system calls directly on the fd.
- IPC::ConnectionBase and related classes now use the Stream API
functions.
- IPC::ServerConnection no longer constructs the socket itself; instead,
a convenience macro, IPC_CLIENT_CONNECTION, is used in place of
C_OBJECT and will generate a static try_create factory function for
the ServerConnection subclass. The subclass is now responsible for
passing the socket constructed in this function to its
ServerConnection base; the socket is passed as the first argument to
the constructor (as a NonnullOwnPtr<Core::Stream::LocalServer>) before
any other arguments.
- The functionality regarding taking over sockets from SystemServer has
been moved to LibIPC/SystemServerTakeover.cpp. The Core::LocalSocket
implementation of this functionality hasn't been deleted due to my
intention of removing this class in the near future and to reduce
noise on this (already quite noisy) PR.
Previously you could pass anything (e.g a text file) to ImageDecoder and
it would "succeed" in decoding it and give you back a 0-frame result.
Let's consider that state a failure instead.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
The overhead from spawning a new ImageDecoder for every decoding job is
way too large and causing other problems as well (#5421)
Let's keep the same decoder open and reuse it as long as it's working.
If the ImageDecoder service crashes while decoding an image for us,
we now recover gracefully and simply return null.
This shields the browser from bugs in our image decoders.
The PIDs were used for sharing shbufs between processes, but now that
we have migrated to file descriptor passing, we no longer need to know
the PID of the other side.
The ImageDecoder service now returns a list of image frames, each with
a duration value.
The code for in-process image decoding is removed from LibWeb, an all
image decode requests are sent out-of-process to ImageDecoder. :^)
This won't scale super well to very long and/or large animations, but
we can work on improving that separately. The main goal here is simply
to stop doing any image decoding inside LibWeb.
Fixes#5165.