1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef __ADB_SOCKET_H
18#define __ADB_SOCKET_H
19
20#include <stddef.h>
21
22#include <memory>
23
24#include "fdevent.h"
25
26struct apacket;
27class atransport;
28
29/* An asocket represents one half of a connection between a local and
30 * remote entity.  A local asocket is bound to a file descriptor.  A
31 * remote asocket is bound to the protocol engine.
32 */
33struct asocket {
34    /* chain pointers for the local/remote list of
35     * asockets that this asocket lives in
36     */
37    asocket* next;
38    asocket* prev;
39
40    /* the unique identifier for this asocket
41     */
42    unsigned id;
43
44    /* flag: set when the socket's peer has closed
45     * but packets are still queued for delivery
46     */
47    int closing;
48
49    // flag: set when the socket failed to write, so the socket will not wait to
50    // write packets and close directly.
51    bool has_write_error;
52
53    /* flag: quit adbd when both ends close the
54     * local service socket
55     */
56    int exit_on_close;
57
58    // the asocket we are connected to
59    asocket* peer;
60
61    /* For local asockets, the fde is used to bind
62     * us to our fd event system.  For remote asockets
63     * these fields are not used.
64     */
65    fdevent fde;
66    int fd;
67
68    // queue of apackets waiting to be written
69    apacket* pkt_first;
70    apacket* pkt_last;
71
72    /* enqueue is called by our peer when it has data
73     * for us.  It should return 0 if we can accept more
74     * data or 1 if not.  If we return 1, we must call
75     * peer->ready() when we once again are ready to
76     * receive data.
77     */
78    int (*enqueue)(asocket* s, apacket* pkt);
79
80    /* ready is called by the peer when it is ready for
81     * us to send data via enqueue again
82     */
83    void (*ready)(asocket* s);
84
85    /* shutdown is called by the peer before it goes away.
86     * the socket should not do any further calls on its peer.
87     * Always followed by a call to close. Optional, i.e. can be NULL.
88     */
89    void (*shutdown)(asocket* s);
90
91    /* close is called by the peer when it has gone away.
92     * we are not allowed to make any further calls on the
93     * peer once our close method is called.
94     */
95    void (*close)(asocket* s);
96
97    /* A socket is bound to atransport */
98    atransport* transport;
99
100    size_t get_max_payload() const;
101};
102
103asocket *find_local_socket(unsigned local_id, unsigned remote_id);
104void install_local_socket(asocket *s);
105void remove_socket(asocket *s);
106void close_all_sockets(atransport *t);
107
108asocket *create_local_socket(int fd);
109asocket *create_local_service_socket(const char* destination,
110                                     const atransport* transport);
111
112asocket *create_remote_socket(unsigned id, atransport *t);
113void connect_to_remote(asocket *s, const char *destination);
114void connect_to_smartsocket(asocket *s);
115
116// Internal functions that are only made available here for testing purposes.
117namespace internal {
118
119#if ADB_HOST
120char* skip_host_serial(char* service);
121#endif
122
123}  // namespace internal
124
125#endif  // __ADB_SOCKET_H
126