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 <deque>
23 #include <memory>
24 #include <string>
25 
26 #include "adb_unique_fd.h"
27 #include "fdevent/fdevent.h"
28 #include "types.h"
29 
30 class atransport;
31 
32 /* An asocket represents one half of a connection between a local and
33  * remote entity.  A local asocket is bound to a file descriptor.  A
34  * remote asocket is bound to the protocol engine.
35  */
36 struct asocket {
37     /* the unique identifier for this asocket
38      */
39     unsigned id = 0;
40 
41     /* flag: set when the socket's peer has closed
42      * but packets are still queued for delivery
43      */
44     int closing = 0;
45 
46     // flag: set when the socket failed to write, so the socket will not wait to
47     // write packets and close directly.
48     bool has_write_error = 0;
49 
50     /* flag: quit adbd when both ends close the
51      * local service socket
52      */
53     int exit_on_close = 0;
54 
55     // the asocket we are connected to
56     asocket* peer = nullptr;
57 
58     /* For local asockets, the fde is used to bind
59      * us to our fd event system.  For remote asockets
60      * these fields are not used.
61      */
62     fdevent* fde = nullptr;
63     int fd = -1;
64 
65     // queue of data waiting to be written
66     IOVector packet_queue;
67 
68     std::string smart_socket_data;
69 
70     /* enqueue is called by our peer when it has data
71      * for us.  It should return 0 if we can accept more
72      * data or 1 if not.  If we return 1, we must call
73      * peer->ready() when we once again are ready to
74      * receive data.
75      */
76     int (*enqueue)(asocket* s, apacket::payload_type data) = nullptr;
77 
78     /* ready is called by the peer when it is ready for
79      * us to send data via enqueue again
80      */
81     void (*ready)(asocket* s) = nullptr;
82 
83     /* shutdown is called by the peer before it goes away.
84      * the socket should not do any further calls on its peer.
85      * Always followed by a call to close. Optional, i.e. can be NULL.
86      */
87     void (*shutdown)(asocket* s) = nullptr;
88 
89     /* close is called by the peer when it has gone away.
90      * we are not allowed to make any further calls on the
91      * peer once our close method is called.
92      */
93     void (*close)(asocket* s) = nullptr;
94 
95     /* A socket is bound to atransport */
96     atransport* transport = nullptr;
97 
98     size_t get_max_payload() const;
99 };
100 
101 asocket *find_local_socket(unsigned local_id, unsigned remote_id);
102 void install_local_socket(asocket *s);
103 void remove_socket(asocket *s);
104 void close_all_sockets(atransport *t);
105 
106 asocket* create_local_socket(unique_fd fd);
107 asocket* create_local_service_socket(std::string_view destination, atransport* transport);
108 
109 asocket *create_remote_socket(unsigned id, atransport *t);
110 void connect_to_remote(asocket* s, std::string_view destination);
111 
112 #if ADB_HOST
113 void connect_to_smartsocket(asocket *s);
114 #endif
115 
116 // Internal functions that are only made available here for testing purposes.
117 namespace internal {
118 
119 #if ADB_HOST
120 bool parse_host_service(std::string_view* out_serial, std::string_view* out_command,
121                         std::string_view service);
122 #endif
123 
124 }  // namespace internal
125 
126 #endif  // __ADB_SOCKET_H
127