mirror of
https://github.com/EQEmu/Server.git
synced 2025-12-24 09:01:29 +00:00
296 lines
9.8 KiB
ReStructuredText
296 lines
9.8 KiB
ReStructuredText
|
|
.. _udp:
|
|
|
|
:c:type:`uv_udp_t` --- UDP handle
|
|
=================================
|
|
|
|
UDP handles encapsulate UDP communication for both clients and servers.
|
|
|
|
|
|
Data types
|
|
----------
|
|
|
|
.. c:type:: uv_udp_t
|
|
|
|
UDP handle type.
|
|
|
|
.. c:type:: uv_udp_send_t
|
|
|
|
UDP send request type.
|
|
|
|
.. c:type:: uv_udp_flags
|
|
|
|
Flags used in :c:func:`uv_udp_bind` and :c:type:`uv_udp_recv_cb`..
|
|
|
|
::
|
|
|
|
enum uv_udp_flags {
|
|
/* Disables dual stack mode. */
|
|
UV_UDP_IPV6ONLY = 1,
|
|
/*
|
|
* Indicates message was truncated because read buffer was too small. The
|
|
* remainder was discarded by the OS. Used in uv_udp_recv_cb.
|
|
*/
|
|
UV_UDP_PARTIAL = 2,
|
|
/*
|
|
* Indicates if SO_REUSEADDR will be set when binding the handle in
|
|
* uv_udp_bind.
|
|
* This sets the SO_REUSEPORT socket flag on the BSDs and OS X. On other
|
|
* Unix platforms, it sets the SO_REUSEADDR flag. What that means is that
|
|
* multiple threads or processes can bind to the same address without error
|
|
* (provided they all set the flag) but only the last one to bind will receive
|
|
* any traffic, in effect "stealing" the port from the previous listener.
|
|
*/
|
|
UV_UDP_REUSEADDR = 4
|
|
};
|
|
|
|
.. c:type:: void (*uv_udp_send_cb)(uv_udp_send_t* req, int status)
|
|
|
|
Type definition for callback passed to :c:func:`uv_udp_send`, which is
|
|
called after the data was sent.
|
|
|
|
.. c:type:: void (*uv_udp_recv_cb)(uv_udp_t* handle, ssize_t nread, const uv_buf_t* buf, const struct sockaddr* addr, unsigned flags)
|
|
|
|
Type definition for callback passed to :c:func:`uv_udp_recv_start`, which
|
|
is called when the endpoint receives data.
|
|
|
|
* `handle`: UDP handle
|
|
* `nread`: Number of bytes that have been received.
|
|
0 if there is no more data to read. You may discard or repurpose
|
|
the read buffer. Note that 0 may also mean that an empty datagram
|
|
was received (in this case `addr` is not NULL). < 0 if a transmission
|
|
error was detected.
|
|
* `buf`: :c:type:`uv_buf_t` with the received data.
|
|
* `addr`: ``struct sockaddr*`` containing the address of the sender.
|
|
Can be NULL. Valid for the duration of the callback only.
|
|
* `flags`: One or more or'ed UV_UDP_* constants. Right now only
|
|
``UV_UDP_PARTIAL`` is used.
|
|
|
|
.. note::
|
|
The receive callback will be called with `nread` == 0 and `addr` == NULL when there is
|
|
nothing to read, and with `nread` == 0 and `addr` != NULL when an empty UDP packet is
|
|
received.
|
|
|
|
.. c:type:: uv_membership
|
|
|
|
Membership type for a multicast address.
|
|
|
|
::
|
|
|
|
typedef enum {
|
|
UV_LEAVE_GROUP = 0,
|
|
UV_JOIN_GROUP
|
|
} uv_membership;
|
|
|
|
|
|
Public members
|
|
^^^^^^^^^^^^^^
|
|
|
|
.. c:member:: size_t uv_udp_t.send_queue_size
|
|
|
|
Number of bytes queued for sending. This field strictly shows how much
|
|
information is currently queued.
|
|
|
|
.. c:member:: size_t uv_udp_t.send_queue_count
|
|
|
|
Number of send requests currently in the queue awaiting to be processed.
|
|
|
|
.. c:member:: uv_udp_t* uv_udp_send_t.handle
|
|
|
|
UDP handle where this send request is taking place.
|
|
|
|
.. seealso:: The :c:type:`uv_handle_t` members also apply.
|
|
|
|
|
|
API
|
|
---
|
|
|
|
.. c:function:: int uv_udp_init(uv_loop_t* loop, uv_udp_t* handle)
|
|
|
|
Initialize a new UDP handle. The actual socket is created lazily.
|
|
Returns 0 on success.
|
|
|
|
.. c:function:: int uv_udp_init_ex(uv_loop_t* loop, uv_udp_t* handle, unsigned int flags)
|
|
|
|
Initialize the handle with the specified flags. At the moment the lower 8 bits
|
|
of the `flags` parameter are used as the socket domain. A socket will be created
|
|
for the given domain. If the specified domain is ``AF_UNSPEC`` no socket is created,
|
|
just like :c:func:`uv_udp_init`.
|
|
|
|
.. versionadded:: 1.7.0
|
|
|
|
.. c:function:: int uv_udp_open(uv_udp_t* handle, uv_os_sock_t sock)
|
|
|
|
Opens an existing file descriptor or Windows SOCKET as a UDP handle.
|
|
|
|
Unix only:
|
|
The only requirement of the `sock` argument is that it follows the datagram
|
|
contract (works in unconnected mode, supports sendmsg()/recvmsg(), etc).
|
|
In other words, other datagram-type sockets like raw sockets or netlink
|
|
sockets can also be passed to this function.
|
|
|
|
.. versionchanged:: 1.2.1 the file descriptor is set to non-blocking mode.
|
|
|
|
.. note::
|
|
The passed file descriptor or SOCKET is not checked for its type, but
|
|
it's required that it represents a valid datagram socket.
|
|
|
|
.. c:function:: int uv_udp_bind(uv_udp_t* handle, const struct sockaddr* addr, unsigned int flags)
|
|
|
|
Bind the UDP handle to an IP address and port.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param addr: `struct sockaddr_in` or `struct sockaddr_in6`
|
|
with the address and port to bind to.
|
|
|
|
:param flags: Indicate how the socket will be bound,
|
|
``UV_UDP_IPV6ONLY`` and ``UV_UDP_REUSEADDR`` are supported.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_getsockname(const uv_udp_t* handle, struct sockaddr* name, int* namelen)
|
|
|
|
Get the local IP and port of the UDP handle.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init` and bound.
|
|
|
|
:param name: Pointer to the structure to be filled with the address data.
|
|
In order to support IPv4 and IPv6 `struct sockaddr_storage` should be
|
|
used.
|
|
|
|
:param namelen: On input it indicates the data of the `name` field. On
|
|
output it indicates how much of it was filled.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_membership(uv_udp_t* handle, const char* multicast_addr, const char* interface_addr, uv_membership membership)
|
|
|
|
Set membership for a multicast address
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param multicast_addr: Multicast address to set membership for.
|
|
|
|
:param interface_addr: Interface address.
|
|
|
|
:param membership: Should be ``UV_JOIN_GROUP`` or ``UV_LEAVE_GROUP``.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_multicast_loop(uv_udp_t* handle, int on)
|
|
|
|
Set IP multicast loop flag. Makes multicast packets loop back to
|
|
local sockets.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param on: 1 for on, 0 for off.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_multicast_ttl(uv_udp_t* handle, int ttl)
|
|
|
|
Set the multicast ttl.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param ttl: 1 through 255.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_multicast_interface(uv_udp_t* handle, const char* interface_addr)
|
|
|
|
Set the multicast interface to send or receive data on.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param interface_addr: interface address.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_broadcast(uv_udp_t* handle, int on)
|
|
|
|
Set broadcast on or off.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param on: 1 for on, 0 for off.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_set_ttl(uv_udp_t* handle, int ttl)
|
|
|
|
Set the time to live.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param ttl: 1 through 255.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_send(uv_udp_send_t* req, uv_udp_t* handle, const uv_buf_t bufs[], unsigned int nbufs, const struct sockaddr* addr, uv_udp_send_cb send_cb)
|
|
|
|
Send data over the UDP socket. If the socket has not previously been bound
|
|
with :c:func:`uv_udp_bind` it will be bound to 0.0.0.0
|
|
(the "all interfaces" IPv4 address) and a random port number.
|
|
|
|
:param req: UDP request handle. Need not be initialized.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param bufs: List of buffers to send.
|
|
|
|
:param nbufs: Number of buffers in `bufs`.
|
|
|
|
:param addr: `struct sockaddr_in` or `struct sockaddr_in6` with the
|
|
address and port of the remote peer.
|
|
|
|
:param send_cb: Callback to invoke when the data has been sent out.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_try_send(uv_udp_t* handle, const uv_buf_t bufs[], unsigned int nbufs, const struct sockaddr* addr)
|
|
|
|
Same as :c:func:`uv_udp_send`, but won't queue a send request if it can't
|
|
be completed immediately.
|
|
|
|
:returns: >= 0: number of bytes sent (it matches the given buffer size).
|
|
< 0: negative error code (``UV_EAGAIN`` is returned when the message
|
|
can't be sent immediately).
|
|
|
|
.. c:function:: int uv_udp_recv_start(uv_udp_t* handle, uv_alloc_cb alloc_cb, uv_udp_recv_cb recv_cb)
|
|
|
|
Prepare for receiving data. If the socket has not previously been bound
|
|
with :c:func:`uv_udp_bind` it is bound to 0.0.0.0 (the "all interfaces"
|
|
IPv4 address) and a random port number.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:param alloc_cb: Callback to invoke when temporary storage is needed.
|
|
|
|
:param recv_cb: Callback to invoke with received data.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. c:function:: int uv_udp_recv_stop(uv_udp_t* handle)
|
|
|
|
Stop listening for incoming datagrams.
|
|
|
|
:param handle: UDP handle. Should have been initialized with
|
|
:c:func:`uv_udp_init`.
|
|
|
|
:returns: 0 on success, or an error code < 0 on failure.
|
|
|
|
.. seealso:: The :c:type:`uv_handle_t` API functions also apply.
|