I've attempted to handle the errors gracefully where it was clear how to
do so, and simple, but a lot of this was just adding
`release_value_but_fixme_should_propagate_errors()` in places.
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.
This encapsulates what our multi-client IPC servers typically do on
startup:
1. Create a Core::LocalServer
2. Take over a listening socket file descriptor from SystemServer
3. Set up an accept handler for incoming connections
IPC::MultiServer does all this for you! All you have to do is provide
the relevant client connection type as a template argument.
These ones all manage their storage internally, whereas the WebContent
and ImageDecoder ones require the caller to manage their lifetime. This
distinction is not obvious to the user without looking through the code,
so an API that makes this clearer would be nice.
Everyone used this hook in the same way: immediately accept() on the
socket and then do something with the newly accepted fd.
This patch simplifies the hook by having LocalServer do the accepting
automatically.
This isn't a complete conversion to ErrorOr<void>, but a good chunk.
The end goal here is to propagate buffer allocation failures to the
caller, and allow the use of TRY() with formatting functions.
Also add slightly richer parse errors now that we can include a string
literal with returned errors.
This will allow us to use TRY() when working with JSON data.
Derivatives of Core::Object should be constructed through
ClassName::construct(), to avoid handling ref-counted objects with
refcount zero. Fixing the visibility means that misuses like this are
more difficult.
This adds a FileWatcher to the LookupServer which watches '/etc/hosts'
for changes during runtime and reloads its contents. If the file is
deleted, m_etc_hosts will be cleared.
Since we now need to access '/etc/hosts' later during runtime, it needs
to be unveiled with read permissions.
This reworks the LookupServer::load_etc_hosts() method to use the
IPv4Address APIs instead of trying to parse an IPv4 address itself.
It also adds a few error checks for invalid entries in /etc/hosts,
trims away leading and trailing whitespace from lines and tries to use
StringView over String.
Since applications using Core::EventLoop no longer need to create a
socket in /tmp/rpc/, and also don't need to listen for incoming
connections on this socket, we can remove a whole bunch of pledges!
The implementation is extremely basic, and is far from fully conforming
to the spec. Among other things, it does not really work in case there
are multiple network adapters.
Nevertheless, it works quite well for the simple case! You can now do
this on your host machine:
$ ping courage.local
and same on your Serenity box:
$ ping host-machine-name.local
This enables support for automatically generating client methods.
With this added the user gets code completion support for all
IPC methods which are available on a connection object.
