• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* Copyright (c) 2012 The Chromium OS 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.
4  */
5 
6 /*
7  * A remote client to the server.
8  */
9 #ifndef CRAS_RCLIENT_H_
10 #define CRAS_RCLIENT_H_
11 
12 #include "cras_types.h"
13 
14 struct cras_client_message;
15 struct cras_message;
16 struct cras_server_message;
17 
18 /* An attached client.
19  *  id - The id of the client.
20  *  fd - Connection for client communication.
21  *  ops - cras_rclient_ops for the cras_rclient.
22  *  supported_directions - Bit mask for supported stream directions.
23  *  client_type - Client type of this rclient. If this is set to value other
24  *                than CRAS_CLIENT_TYPE_UNKNOWN, rclient will overwrite incoming
25  *                messages' client type.
26  */
27 struct cras_rclient {
28 	struct cras_observer_client *observer;
29 	size_t id;
30 	int fd;
31 	const struct cras_rclient_ops *ops;
32 	int supported_directions;
33 	enum CRAS_CLIENT_TYPE client_type;
34 };
35 
36 /* Operations for cras_rclient.
37  * handle_message_from_client - Entry point for handling a message from the
38  * corresponded client.
39  * send_message_to_client - Method for sending message to the corresponded
40  * client.
41  * destroy - Method to destroy and free the cras_rclient.
42  */
43 struct cras_rclient_ops {
44 	int (*handle_message_from_client)(struct cras_rclient *,
45 					  const struct cras_server_message *,
46 					  int *fds, unsigned int num_fds);
47 	int (*send_message_to_client)(const struct cras_rclient *,
48 				      const struct cras_client_message *,
49 				      int *fds, unsigned int num_fds);
50 	void (*destroy)(struct cras_rclient *);
51 };
52 
53 /* Creates an rclient structure.
54  * Args:
55  *    fd - The file descriptor used for communication with the client.
56  *    id - Unique identifier for this client.
57  *    conn_type - Client connection type.
58  * Returns:
59  *    A pointer to the newly created rclient on success, NULL on failure.
60  */
61 struct cras_rclient *cras_rclient_create(int fd, size_t id,
62 					 enum CRAS_CONNECTION_TYPE conn_type);
63 
64 /* Destroys an rclient created with "cras_rclient_create".
65  * Args:
66  *    client - The client to destroy.
67  */
68 void cras_rclient_destroy(struct cras_rclient *client);
69 
70 /* Handles a received buffer from the client.
71  * Args:
72  *    client - The client that received this message.
73  *    buf - The raw byte buffer the client sent. It should contain a valid
74  *      cras_server_message.
75  *    buf_len - The length of |buf|.
76  *    fds - Array of valid file descriptors sent by the remote client.
77  *    num_fds - Length of |fds|.
78  * Returns:
79  *    0 on success, otherwise a negative error code.
80  */
81 int cras_rclient_buffer_from_client(struct cras_rclient *client,
82 				    const uint8_t *buf, size_t buf_len,
83 				    int *fds, int num_fds);
84 
85 /* Sends a message to the client.
86  * Args:
87  *    client - The client to send the message to.
88  *    msg - The message to send.
89  *    fds - Array of file descriptors or null
90  *    num_fds - Number of entries in the fds array.
91  * Returns:
92  *    number of bytes written on success, otherwise a negative error code.
93  */
94 int cras_rclient_send_message(const struct cras_rclient *client,
95 			      const struct cras_client_message *msg, int *fds,
96 			      unsigned int num_fds);
97 
98 #endif /* CRAS_RCLIENT_H_ */
99