xref: /netbsd-src/external/gpl3/gcc/dist/libcc1/connection.hh (revision 0a3071956a3a9fdebdbf7f338cf2d439b45fc728)
1 /* Plugin connection declarations
2    Copyright (C) 2014-2022 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 #ifndef CC1_PLUGIN_CONNECTION_HH
21 #define CC1_PLUGIN_CONNECTION_HH
22 
23 #include "status.hh"
24 #include "callbacks.hh"
25 
26 namespace cc1_plugin
27 {
28   // The connection class represents one side of the connection
29   // between the gdb-side library and the gcc plugin.  It handles the
30   // low-level details of reading and writing data.
31   class connection
32   {
33   public:
34 
35     connection (int fd)
36       : m_fd (fd),
37 	m_aux_fd (-1),
38 	m_callbacks ()
39     {
40     }
41 
42     connection (int fd, int aux_fd)
43       : m_fd (fd),
44 	m_aux_fd (aux_fd),
45 	m_callbacks ()
46     {
47     }
48 
49     virtual ~connection () = default;
50 
51     connection (const connection &) = delete;
52     connection &operator= (const connection &) = delete;
53 
54     // Send a single character.  This is used to introduce various
55     // higher-level protocol elements.
56     status send (char c);
57 
58     // Send data in bulk.
59     status send (const void *buf, int len);
60 
61     // Read a single byte from the connection and verify that it
62     // matches the argument C.
63     status require (char c);
64 
65     // Read data in bulk.
66     status get (void *buf, int len);
67 
68     // This is called after a query (remote function call) has been
69     // sent to the remote.  It waits for a response packet.  The
70     // response character is read before returning.  Any query packets
71     // sent from the remote while waiting for a response are handled
72     // by this function.
73     status wait_for_result ()
74     {
75       return do_wait (true);
76     }
77 
78     // Read and respond to query packets sent by the remote.  This
79     // function returns when the connection is closed.
80     status wait_for_query ()
81     {
82       return do_wait (false);
83     }
84 
85     // Register a callback with this connection.  NAME is the name of
86     // the method being registered.  FUNC is the function.  It must
87     // know how to decode its own arguments.  When a query packet is
88     // received by one of the wait_* methods, the corresponding
89     // callback is invoked.
90     void add_callback (const char *name, callback_ftype *func)
91     {
92       m_callbacks.add_callback (name, func);
93     }
94 
95     virtual void print (const char *)
96     {
97     }
98 
99   private:
100 
101     // Helper function for the wait_* methods.
102     status do_wait (bool);
103 
104     // The file descriptor.
105     int m_fd;
106 
107     // An auxiliary file descriptor, or -1 if none.
108     int m_aux_fd;
109 
110     // Callbacks associated with this connection.
111     callbacks m_callbacks;
112   };
113 }
114 
115 #endif // CC1_PLUGIN_CONNECTION_HH
116