NetServices: Notify any async listeners when a request completes early.

The API allows a user to end parsing responses earlier if the response has a
client (4xx) or server (5xx) error code. The end user should still be notified
of this result, so that they can act.

Change-Id: I11f2ab296658f767b5b34e10badb54de27aab494
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5910
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
Reviewed-by: Adrien Destugues <pulkomandy@pulkomandy.tk>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>

NetServices: format code using `haiku-format`

This commit formats all the netservices2 code with the `haiku-format` tool from
https://github.com/owenca/haiku-format (commit aa7408e), with the following
customizations:
* SpaceBeforeRangeBasedForLoopColon is set to false
* Braces before a catch block are not wrapped
* Most headers, except for ExclusiveBorrow.h, have been manually reformatted
to adhere to Haiku's header format (issue #19 in the repository)

Change-Id: I693c4515cf26402e48f35d1213ab6d5fcf14bd1e

NetServices: Refactor to make HttpParser stateful

This change refactors various parts of the HTTP parsing. The HttpParser now
tracks what part of the message needs to be received next, and throws an error
if the object is used in the wrong way (when the caller requests to parse the
wrong part of he message).

The metadata about the transmission is now also saved in te parser. There is
partial work in there to start exposing the 'bytes written', which in
compressed streams is expected to differ from the bytes read. This is not
used yet.

This also simplifies the state tracking done by BHttpSession::Request.

Change-Id: I8532c6a5c8776456ea8bbccd6df7a44bac92b60d

NetServices: use BBorrow<BDataIO> for custom body targets

Change-Id: Ib2d4b0ca3689338d906f943295278c086c6f2c83

NetServices: Add debugging constants and messages

These allow for additional messages about the progress/status of the request.
For now, the messages are sent unconditionally, though it may be reasonable to
in the future switch to sending them only when enabled.

Change-Id: Ic45a0055037af02c689494fa5ce0acd03592ad7e

NetServices: Rework parsing of content-length and move to HttpParser

This fixes a bug in the HttpAuthTest, and in general, moves responsibility of determining
the shape and size of the content to the right place.

Still to do is to fix the case where there really is a variable length content. This will
now probably error out as a connection closed error.

Change-Id: I13c20028e834cc9af8c7bc1d7d7613bf60838e64

NetServices: Add custom error message to BNetworkRequestError

Change-Id: I03970762531a689e25cd78a1091aecf755ee87ce

NetServices: add the HttpSerializer helper to help serialize requests

Change-Id: Ide1e2d387884ce4cf2d406057960cd0732d61f38

NetServices: move HttpBuffer and HttpParser into their own header/source

Change-Id: I5bc0d9df6f94c2cf1c39baa6206bf6f1db284705

NetServices: Implement controls on the number of concurrent requests.

This change allows the user to control how many concurrent request can be done
per session. This is going to be helpful to running the tests as well; they were
all fired up in parallel, which sometimes leads to our test server refusing a
connection.

Change-Id: I4f1f40b28b8e0199ea5589b36cd8d00ecd849a63

NetServices: Rewrite the control thread loop to prepare for filtering of requests to do

Change-Id: I72d5f1ddd499f8fb227af5ee78111a60eb50b1f5

NetServices: Implement asynchronous status update messages.

The integration PostTest has a basic test that the expected messages are sent and
have the expected data fields. The gist is documented in book.dox.

To do are the messages around SSL. However, that functionality is also not
implemented yet, so there is nothing to send.

Change-Id: Ib8f36ed32f9854d643d8256338b71af7067059f0

NetServices: Refactor the parsing code into a HttpParser helper class

Change-Id: Ib03aacc36d46318c8870554f794ff66db4cce063

NetServices: add HttpBuffer to encapsulate buffered reading

Change-Id: I7ec3189c3cf459fccae4ffac44702fd6b8c12ac9

NetServices: When the response Content-Length is 0, do not expect a body.

Change-Id: Ia715b44289dc3c64c2b834f954421413cbc3593c

NetServices: Add support for an input body in a request and handle this with redirects.

Change-Id: Id2399d49aa673469c8c04ebd13884cdbcb24112d

NetServices: Implement BHttpSession::Cancel()

Change-Id: Iff0a7726e57f3e6bd4e9d0ebac08a370d25a62d7

NetServices: Add/rework the MaxRedirections, Timeout and StopOnError options

Change-Id: I4e59b51c16c6777941dc92ce02505386257dad03

NetServices: Implement BHttpStatusCode, BHttpStatusClass and Redirects

The user of the API can set whether redirects should be followed, and if so,
how many. This is part of the BHttpRequest API. The BHttpSession then follows
those instructions, and executes the maximum number of redirects the user
would like to follow.

As part of this commit, the BHttpStatusClass and BHttpStatusCodes helper enums
have been added, to give a friendlier access to HTTP status codes and status
classes.

Change-Id: Ic8c9e3fda158e2cce549c8f1d360951f7ac83311

NetServices: implement support for HEAD requests and 204 responses.

These particular responses will not have a body. This is now handled by the
BHttpSession object. There is also a minor fix in here that prevents a crash
when multiple requests are handled by the DataThread at the same time, and not
all of the requests have events.

Change-Id: I7f47d8b3cd8491c8193275be4b3fc1080780fa20

NetServices: partial implementation of the receive function

This initial implementation contains a lot of extra debuggin output that will
be removed in future changes. It is now possible to run a simple GET request
to the test server with gzip encoding.

Change-Id: I2c402e5cf80b94b366563888222a891a1b094b7a

NetServices: implement writing in the data thread.

Change-Id: Ideb63f9f96bf62ea7d9ce63df22805473273855d

NetServices: implement hostname resolution and connection for BHttpRequest

BHttpSession::Execute() moves the request into the session, and returns a future BHttpResponse
object. Currently implemented are resolving the hostname, and opening the connection.

There is some scaffolding for the actual data transfer.

Change-Id: I5a8a7a7f8680036b91cdba4beee140bbed6bfd5a

NetServices: Initial implementation of BHttpResult

Incomplete class, but will provide the basis to start working on the internals of the BHttpSession.

Change-Id: I3ca14b7bd823fc1b4a5a32f5784592d214c4e9a7

netservices: Flesh out BHttpSession::Impl data and control structures

Change-Id: I4230570ea8339b12d855f7de7fa72e4664013e2d

NetServices: Add skeleton BHttpSession class and its documentation

Change-Id: Ia8a35588422908f6fe9b839ce239fb478baf298b