This patchset makes ProtocolServer stream the downloads to its client
(LibProtocol), and as such changes the download API; a possible
download lifecycle could be as such:
notation = client->server:'>', server->client:'<', pipe activity:'*'
```
> StartDownload(GET, url, headers, {})
< Response(0, fd 8)
* {data, 1024b}
< HeadersBecameAvailable(0, response_headers, 200)
< DownloadProgress(0, 4K, 1024)
* {data, 1024b}
* {data, 1024b}
< DownloadProgress(0, 4K, 2048)
* {data, 1024b}
< DownloadProgress(0, 4K, 1024)
< DownloadFinished(0, true, 4K)
```
Since managing the received file descriptor is a pain, LibProtocol
implements `Download::stream_into(OutputStream)`, which can be used to
stream the download into any given output stream (be it a file, or
memory, or writing stuff with a delay, etc.).
Also, as some of the users of this API require all the downloaded data
upfront, LibProtocol also implements `set_should_buffer_all_input()`,
which causes the download instance to buffer all the data until the
download is complete, and to call the `on_buffered_download_finish`
hook.
This makes most operations thread safe, especially so that they
can safely be used in the Kernel. This includes obtaining a strong
reference from a weak reference, which now requires an explicit
call to WeakPtr::strong_ref(). Another major change is that
Weakable::make_weak_ref() may require the explicit target type.
Previously we used reinterpret_cast in WeakPtr, assuming that it
can be properly converted. But WeakPtr does not necessarily have
the knowledge to be able to do this. Instead, we now ask the class
itself to deliver a WeakPtr to the type that we want.
Also, WeakLink is no longer specific to a target type. The reason
for this is that we want to be able to safely convert e.g. WeakPtr<T>
to WeakPtr<U>, and before this we just reinterpret_cast the internal
WeakLink<T> to WeakLink<U>, which is a bold assumption that it would
actually produce the correct code. Instead, WeakLink now operates
on just a raw pointer and we only make those constructors/operators
available if we can verify that it can be safely cast.
In order to guarantee thread safety, we now use the least significant
bit in the pointer for locking purposes. This also means that only
properly aligned pointers can be used.
If we're sharing buffers, we only want to share trivial structures
as anything else could potentially share internal pointers, which
most likely is going to cause problems due to different address
spaces.
Fix the GUI::SystemTheme structure, which was not trivial, which
is now caught at compile time.
Fixes#3650
Clients now receive HTTP status codes like 200, 404, etc.
Note that a 404 with content is still considered a "successful"
download from ProtocolServer's perspective. It's up to the client
to interpret the status code.
I'm not sure if this is the best API, but it'll work for now.
You can now pass a dictionary of request headers when starting a new
download in ProtocolServer.
The HTTP and HTTPS protocol will include the headers in their requests.
Core::Object derived objects should always have private constructors
and use construct() for construction. This prevents accidentally
keeping them in non-reference-counting containers.
It didn't feel right to have a "DHCPClient" in a "Servers" directory.
Rename this to Services to better reflect the type of programs we'll
be putting in there.
We now store the response headers in a download object on the protocol
server side and pass it to the client when finishing up a download.
Response headers are passed as an IPC::Dictionary. :^)
StartDownload requests for unhandled protocols (or invalid URLs) will
now refuse to load instead of asserting. A failure code is sent back
to LibProtocol and Protocol::Client::start_download() returns nullptr.
Fixes#1604.
This feels a lot more consistent and Unixy:
create_shared_buffer() => shbuf_create()
share_buffer_with() => shbuf_allow_pid()
share_buffer_globally() => shbuf_allow_all()
get_shared_buffer() => shbuf_get()
release_shared_buffer() => shbuf_release()
seal_shared_buffer() => shbuf_seal()
get_shared_buffer_size() => shbuf_get_size()
Also, "shared_buffer_id" is shortened to "shbuf_id" all around.
This allows RefPtr to be stored in a HashTable<RefPtr<T>> :^)
It's unfortunate about the const_casts. We'll need to fix HashMap::get
to play nice with non-const Traits<T>::PeekType at some point.
As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.
For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.
Going forward, all new source files should include a license header.
Lock each directory before entering it so when using -j, the same
dependency isn't built more than once at a time.
This doesn't get full -j parallelism though, since one make child
will be sitting idle waiting for flock to receive its lock and
continue making (which should then do nothing since it will have
been built already). Unfortunately there's not much that can be
done to fix that since it can't proceed until its dependency is
built by another make process.
Allow everything to be built from the top level directory with just
'make', cleaned with 'make clean', and installed with 'make
install'. Also support these in any particular subdirectory.
Specifying 'make VERBOSE=1' will print each ld/g++/etc. command as
it runs.
Kernel and early host tools (IPCCompiler, etc.) are built as
object.host.o so that they don't conflict with other things built
with the cross-compiler.
Instead of passing the PIDs back and forth in a handshake "Greet"
message, just use getsockopt(SO_PEERCRED) on both sides to get the same
information from the kernel.
This is a nice little simplification of the IPC protocol, although it
does not get rid of the handshake since we still have to pass the
"client ID" from the server to each client so they know how to refer
to themselves. This might not be necessary and we might be able to get
rid of this later on.
This matches what we're already calling the server-side subclasses
better, though we'll probably want to find some better names for the
client-side classes eventually.
LibProtocol::Client::start_download() now gives you a Download object
with convenient hooks (on_finish & on_progress).
Also, the IPC handshake is snuck into the Client constructor, so you
don't need to perform it after instantiating a Client.
This makes using LibProtocol much more pleasant. :^)
The DownloadFinished message from the server now includes a buffer ID
that can be mapped into the client program.
To avoid prematurely destroying the buffer, the server will hang on to
it until the client lets it know that they're all good. That's what the
ProtocolServer::DisownSharedBuffer message is about.
In the future it would be nice if the kernel had a mechanism to allow
passing ownership of a shared buffer along with an IPC message somehow.
This patch adds ProtocolServer, a server that handles network requests
on behalf of its clients. The first protocol implemented is HTTP.
The idea here is to use a plug-in architecture where any number of
protocols can be added and implemented without having to mess around
with each client program that wants to use the protocol.
A simple client API is provided through LibProtocol::Client. :^)