1/* Connect implementation
2 Copyright (C) 2014-2017 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#include <cc1plugin-config.h>
21#include <string>
22#include <unistd.h>
23#include <sys/types.h>
24#include <string.h>
25#include <errno.h>
26#include "marshall.hh"
27#include "connection.hh"
28#include "rpc.hh"
29
30cc1_plugin::connection::~connection ()
31{
32}
33
34void
35cc1_plugin::connection::print (const char *)
36{
37}
38
39cc1_plugin::status
40cc1_plugin::connection::send (char c)
41{
42 if (write (m_fd, &c, 1) != 1)
43 return FAIL;
44 return OK;
45}
46
47cc1_plugin::status
48cc1_plugin::connection::send (const void *buf, int len)
49{
50 if (write (m_fd, buf, len) != len)
51 return FAIL;
52 return OK;
53}
54
55cc1_plugin::status
56cc1_plugin::connection::require (char c)
57{
58 char result;
59
60 if (read (m_fd, &result, 1) != 1
61 || result != c)
62 return FAIL;
63
64 return OK;
65}
66
67cc1_plugin::status
68cc1_plugin::connection::get (void *buf, int len)
69{
70 if (read (m_fd, buf, len) != len)
71 return FAIL;
72 return OK;
73}
74
75cc1_plugin::status
76cc1_plugin::connection::do_wait (bool want_result)
77{
78 while (true)
79 {
80 char result;
81 fd_set read_set;
82
83 FD_ZERO (&read_set);
84 FD_SET (m_fd, &read_set);
85 if (m_aux_fd != -1)
86 FD_SET (m_aux_fd, &read_set);
87
88 int nfds = select (FD_SETSIZE, &read_set, NULL, NULL, NULL);
89 if (nfds == -1)
90 {
91 if (errno == EINTR)
92 continue;
93 return FAIL;
94 }
95
96 // We have to check the stderr fd first, to avoid a possible
97 // blocking scenario when do_wait is called reentrantly. In
98 // such a call, if we handle the primary fd first, then we may
99 // re-enter this function, read from gcc's stderr, causing the
100 // outer invocation of this function to block when trying to
101 // read.
102 if (m_aux_fd != -1 && FD_ISSET (m_aux_fd, &read_set))
103 {
104 char buf[1024];
105 int n = read (m_aux_fd, buf, sizeof (buf) - 1);
106 if (n < 0)
107 return FAIL;
108 if (n > 0)
109 {
110 buf[n] = '\0';
111 print (buf);
112 }
113 }
114
115 if (FD_ISSET (m_fd, &read_set))
116 {
117 int n = read (m_fd, &result, 1);
118 if (n == 0)
119 return want_result ? FAIL : OK;
120 if (n != 1)
121 return FAIL;
122
123 switch (result)
124 {
125 case 'R':
126 // The reply is ready; the caller will unmarshall it.
127 return want_result ? OK : FAIL;
128
129 case 'Q':
130 // While waiting for a reply, the other side made a method
131 // call.
132 {
133 // Use an argument_wrapper here to simplify management
134 // of the string's lifetime.
135 argument_wrapper<char *> method_name;
136
137 if (!method_name.unmarshall (this))
138 return FAIL;
139
140 callback_ftype *callback
141 = m_callbacks.find_callback (method_name);
142 // The call to CALLBACK is where we may end up in a
143 // reentrant call.
144 if (callback == NULL || !callback (this))
145 return FAIL;
146 }
147 break;
148
149 default:
150 return FAIL;
151 }
152 }
153 }
154}
155