This was a huge work, but now UDP is usable as seen in the examples.
Instead of relying on 'connect()', just do 'sendto()' and 'recvfrom()'
as they are universal. Multicast address can only be connected in
IPv4, IPv6 wasn't working and I'm not sure the IPv4 is portable to
other platforms.
Dialer will auto-join multicast groups is the dialed address is
one. Multicast properties such as time to live (hops) and loopback can
be configured. When joining multicast groups, the local
address/interface can be configured by 'IP@IFACE' format, with
'@IFACE' being optional.
Dialers will now auto-bind, so it can receive data as dialers are
expected to be bi-directional. One can manually specify the binding
address if there is such need.
Since datagrams must be read in their full size, otherwise the
remaining bits are dropped, expose next_datagram_size_query() in both
Efl.Net.Socket.Udp and Efl.Net.Server.Udp.Client.
To finalize UDP for real we need to introduce an 'Efl_Net_Ip_Address'
structure to serve as both IPv4 and IPv6 and expose 'sendto()' and
'recvfrom()'. These will come later as this commit is already too big.
Instead of using 'bool', which requires a parameter to be useful, make
them toggle of the default value.
Adapt names to make more sense in that context.
This is handful to error the copier with ETIMEDOUT if there are no
reads or writes in the given amount of time.
Since copiers are usable to download data or handle network clients,
it's easy to set a timeout and disconnect, let's say UDP clients that
are gone.
This is the initial UDP server that works similarly to the TCP one,
however under the hood it's widely different since the socket is
reused for all "clients", thus needs a new Efl.Net.Server.Udp.Client
(Efl.Net.Socket) as Efl.Net.Socket.Udp exposes the fd and options such
as 'cork', which would interfere in other clients.
The main socket will read the packets and find an existing client to
feed it. If no client exists, then it will create one if not overr
limit. Since there is no kernel-queuing as done by listen()/accept(),
the 'no reject' case will just accept the client anyway.
Next commits will improve UDP server handling with some advanced
features:
- join multicast groups
- bind to a specific interface (SO_BINDTODEVICE)
- block packets going out of local network (SO_DONTROUTE)
- specify priorities (SO_PRIORITY)
instead of blindly reading and writing, which can lead to hangs due no
server, let's use can_read and can_write to do the operations, this
won't let us believe we can read when we can't.
it's also the recommended approach, so let's show that in the examples
so users don't copy&paste incorrect stuff :-)
Sometimes we want to handle both IPv4 and IPv6 in the same socket,
instead of spawning 2 servers, one for each protocol. That is achieved
by means of disabling IPV6_V6ONLY socket option, present in most
recent platforms.
Like existing ecore_con code, this does not use SOCKSv5 UDP
proxy. It's kinda cumbersome to add since requires a keep alive TCP
connection to the server, a second UDP channel and framing around the
original UDP frame.
Added UDP_CORK (if present) to match TCP_UDP present in TCP sockets,
this allows one to execute multiple write() calls that will result in
a single datagram, generated when CORK becomes FALSE again.
The efl_io_copier_example.c now accepts this as output. There is no
input UDP as there is no way to notify the server of a connection
(since such thing doesn't exit), usually servers react after a
datagram is received, replying to the source.
It has been discussed on the ML (thread: "[RFC] rename efl_self") and
IRC, and has been decided we should rename it to this in order to avoid
confusion with the already established meaning of self which is very
similar to what we were using it for, but didn't have complete overlap.
Kudos to Marcel Hollerbach for initiating the discussion and
fighting for it until he convinced a significant mass. :)
This commit breaks API, and depending on compiler potentially ABI.
@feature
The Efl.Net.Dialer.Websocket is just like other Efl.Net.Dialers: you
can dial, you can close, monitor connected/address resolved and so
on. And you can use WebSocket primitives and events such as
text_send(), binary_send(), ping() and close_request() (since
WebSockets use a close process where you should state a close
reason). See efl_net_dialer_websocket_example.c
Even if WebSocket is a message-based protocol (like "packets" from
UDP), you can use efl_net_dialer_websocket_streaming_mode_set() to
tell it to handle text or binary messages as a stream. Then all the
Efl.Io.Reader and Efl.Io.Writer APIs work as expected, see
efl_io_copier_example.c updates.
The use of low-level interfaces such as Efl.Io.Reader and
Efl.Io.Writer are not that user-friendly as they can handle partial
data.
Classes such as Efl.Io.Copier makes them easy to use, but they need a
reader (source) or writer (destination) and in our examples we used
fixed buffers or some existing streams (stdin/stdout/stderr,
networking...).
However, if interactively we need to produce some data to be sent,
such as implementing some networking protocols, we'd have to write our
own Efl.Io.Reader and Efl.Io.Writer classes to handle the buffering.
Not anymore! With Efl.Io.Queue you can write stuff to it and it will
buffer to memory. Once stuff is read, it will automatically remove
those bytes from buffer.
This class implements the Efl.Net.Dialer interface using libcurl to
perform HTTP requests. That means it's an Efl.Net.Dialer,
Efl.Net.Socket, Efl.Io.Reader, Efl.Io.Writer and Efl.Io.Closer, thus
being usable with Efl.Io.Copier as demonstrated in the
efl_io_copier_example.c
Efl.Net.Server defines how to accept new connections, doing the
bind(), listen() and accept() for protocols such as TCP.
Efl.Net.Dialer defines to to reach a server.
Both are based on Efl.Net.Socket as communication interface that is
based on Efl.Io.Reader, Efl.Io.Writer and Efl.Io.Closer, thus being
usable with code such as Efl.Io.Copier.
The Server will emit an event "client,add" with the established
Socket, which is a child and can be closed by both the server or the
user.
The Dialer extends the Socket and allows for creating one given an
address, that will be resolved and connected.
TCP is the initial implementation so we an validate the
interfaces. UDP, Unix-Local and SSL will come later as derivate
classes.
The examples are documented and should cover the basic principles:
- efl_io_copier_example can accept "tcp://IP:PORT" and will work as a
"netcat", can send data from socket, file or stdin to a socket,
file, stdout or stderr.
- efl_net_server_example listens for connections and can either reply
"Hello World!" and take some data or work as an echo-server,
looping back all received data to the user.
More complex interactions that require a "chat" between client and
server will be covered with new classes later, such as a queue that
empties itself once data is read.
These interfaces allows generic operations on objects that can store
or provide data, such as a file or a buffer.
With well defined interfaces and events we can create code such as
Efl.Io.Copier, that will link a source with a destination and
progressively copy data as they appear.
This reverts commit 546ff7bbba788ec834c5608361c0834853f2d5d7.
It seems that eo_del() is useful and removing it was creating bugs.
The issue is that the way we defined parents in eo, both the parent and
the programmer share a reference to the object. When we eo_unref() that
reference as the programmer, eo has no way to know it's this specific
reference we are freeing, and not a general one, so in some
circumstances, for example:
eo_ref(child);
eo_unref(child); // trying to delete here
eo_unref(container); // container is deleted here
eo_unref(child); // child already has 0 refs before this point.
We would have an issue with references and objects being freed too soon
and in general, issue with the references.
Having eo_del() solves that, because this one explicitly unparents if
there is a parent, meaning the reference ownership is explicitly taken
by the programmer.
eo_del() is essentially a convenience function around "check if has
parent, and if so unparent, otherwise, unref". Which should be used when
you want to delete an object although it has a parent, and is equivalent
to eo_unref() when it doesn't have one.
We used to have eo_del() as the mirrored action to eo_add(). No longer,
now you just always eo_unref() to delete an object. This change makes it
so the reference of the parent is shared with the reference the
programmer has. So eo_parent_set(obj, NULL) can free an object, and so
does eo_unref() (even if there is a parent).
This means Eo no longer complains if you have a parent during deletion.
I just ran my script (email to follow) to migrate all of the EFL
automatically. This commit is *only* the automatic conversion, so it can
be easily reverted and re-run.
Summary:
The socket API is different on Windows and on Linux.
This is the perfect example where we need to abstract the socket API in Eina :
1) to avoid all these includes specific to sockets
2) to avoid on Windows undefined behavior : close(socket); is undefined behavior if socket is indeed a socket
Reviewers: jpeg
Reviewed By: jpeg
Subscribers: cedric, jpeg
Projects: #efl
Differential Revision: https://phab.enlightenment.org/D3441
Summary:
Checking if client is NULL before freeing is not of much use. If it is NULL, it would have crashed before when it was dereferenced in printf. So checking NULL before dereferencing.
Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>
Reviewers: cedric
Reviewed By: cedric
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D3151
Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>
Summary:
Checking if client is NULL before freeing is not of much use. If it is NULL, it would have crashed before when it was dereferenced in printf. So checking NULL before dereferencing.
Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>
Reviewers: cedric
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D3088
Signed-off-by: Cedric BAIL <cedric@osg.samsung.com>
Summary:
pd was dereferenced and then checked for NULL. If it was NULL, the program would crash much before. So fixed that.
Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>
Reviewers: cedric, stefan_schmidt
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D3031
Summary:
cd was dereferenced and then was checked for NULL. If cd is NULL, it would crash before itself. So checking for NULL before dereferencing cd.
Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>
Reviewers: cedric, stefan_schmidt
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D3009
Summary:
Relating to D3010. This patch is code cleanup. Have done dos2unix. After this will update D3010 bug.
Signed-off-by: Srivardhan Hebbar <sri.hebbar@samsung.com>
Reviewers: cedric, stefan_schmidt
Subscribers: cedric
Differential Revision: https://phab.enlightenment.org/D3025