1 // Copyright 2014 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
7 import "mojo/services/public/interfaces/network/net_address.mojom";
8 import "mojo/services/public/interfaces/network/network_error.mojom";
10 // UDPSocket and UDPSocketClient represent a UDP socket and its client. The
11 // typical flow of using the interfaces is:
12 // - Acquire a UDPSocket interface pointer and set a UDPSocketClient instance.
13 // - (optional) Set options which are allowed prior to Bind().
15 // - (optional) Set options which are allowed after Bind().
16 // - Send / request to receive datagrams. Received datagrams will be delivered
17 // to UDPSocketClient.OnReceived().
19 [Client=UDPSocketClient]
21 // Allows the socket to share the local address to which it will be bound with
22 // other processes. Should be called before Bind().
23 // (This is equivalent to SO_REUSEADDR of the POSIX socket API.)
24 AllowAddressReuse() => (NetworkError result);
26 // Binds the socket to the given address.
27 // |bound_addr| is non-NULL on success. It might not be the same as |addr|.
28 // For example, if port 0 is used in |addr|, an available port is picked and
29 // returned in |bound_addr|.
30 Bind(NetAddress addr) => (NetworkError result, NetAddress? bound_addr);
32 // Sets the OS send buffer size (in bytes) for the socket. The socket must be
34 SetSendBufferSize(uint32 size) => (NetworkError result);
36 // Sets the OS receive buffer size (in bytes) for the socket. The socket must
38 SetReceiveBufferSize(uint32 size) => (NetworkError result);
40 // Negotiates the maximum number of pending SendTo() requests. If
41 // |requested_size| is set to 0, this method queries the current settings.
43 // The service stores SendTo() requests in a queue while they are waiting to
44 // be executed (i.e., while they are waiting to be placed in the OS send
45 // buffer and sent out). This method negotiates how many requests (not bytes)
46 // this queue is able to store. If the queue is full, the service fails new
47 // requests directly with error code ERR_INSUFFICIENT_RESOURCES and discards
48 // those datagrams. If the client wants to avoid such failures, it needs to
49 // keep track of how many SendTo() calls are pending and make sure the number
50 // doesn't exceed the result of this method.
51 NegotiateMaxPendingSendRequests(uint32 requested_size)
52 => (uint32 actual_size);
54 // Notifies that the client is ready to accept |number| of datagrams.
55 // Correspondingly, OnReceived() of the UDPSocketClient interface will be
56 // called |number| times (errors also count), unless the connection is closed
59 // It is allowed to call this method again before the previous request is
60 // completely satisfied. For example:
61 // service->ReceiveMore(3);
63 // // OnReceived() is called.
64 // // OnReceived() is called.
66 // service->ReceiveMore(3);
67 // // The client expects 4 more calls to OnReceived().
69 // Please note that how ReceiveMore() is used will affect performance
70 // significantly. For example:
72 // service->ReceiveMore(3);
73 // // OnReceived() is called.
74 // // OnReceived() is called.
75 // // OnReceived() is called.
78 // service->ReceiveMore(1);
79 // // OnReceived() is called.
80 // service->ReceiveMore(1);
81 // // OnReceived() is called.
82 // service->ReceiveMore(1);
83 // // OnReceived() is called.
85 // It is very likely that approach 1 will perform better than approach 2,
86 // because in approach 2 getting every datagram takes at least the time of a
87 // round trip to the service side.
88 ReceiveMore(uint32 datagram_number);
90 // Sends data to the specified destination. The socket must be bound.
91 // On success, |result.code| is a non-negative number indicating how many
92 // bytes have been written. Otherwise, it is a network error code, including
93 // (but not limited to):
94 // - ERR_INSUFFICIENT_RESOURCES (-12): The service doesn't have sufficient
95 // resource to complete the operation. One possible cause is that the client
96 // tries to send too many datagrams in a short period of time.
97 // TODO(yzshen): Formalize Mojo networking error codes.
98 SendTo(NetAddress dest_addr, array<uint8> data) => (NetworkError result);
101 interface UDPSocketClient {
102 // On success, |src_addr| and |data| are non-NULL, and |result.code| is a
103 // non-negative number indicating how many bytes have been received. On
104 // failure, |result.code| is a network error code.
105 OnReceived(NetworkError result, NetAddress? src_addr, array<uint8>? data);