1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
|
/* Host support routines for MinGW, for GDB, the GNU debugger.
Copyright (C) 2006-2015 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "main.h"
#include "serial.h"
#include "event-loop.h"
#include "gdb_select.h"
#include "readline/readline.h"
#include <windows.h>
/* This event is signalled whenever an asynchronous SIGINT handler
needs to perform an action in the main thread. */
static HANDLE sigint_event;
/* When SIGINT_EVENT is signalled, gdb_select will call this
function. */
struct async_signal_handler *sigint_handler;
/* Return an absolute file name of the running GDB, if possible, or
ARGV0 if not. The return value is in malloc'ed storage. */
char *
windows_get_absolute_argv0 (const char *argv0)
{
char full_name[PATH_MAX];
if (GetModuleFileName (NULL, full_name, PATH_MAX))
return xstrdup (full_name);
return xstrdup (argv0);
}
/* Wrapper for select. On Windows systems, where the select interface
only works for sockets, this uses the GDB serial abstraction to
handle sockets, consoles, pipes, and serial ports.
The arguments to this function are the same as the traditional
arguments to select on POSIX platforms. */
int
gdb_select (int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
struct timeval *timeout)
{
static HANDLE never_handle;
HANDLE handles[MAXIMUM_WAIT_OBJECTS];
HANDLE h;
DWORD event;
DWORD num_handles;
/* SCBS contains serial control objects corresponding to file
descriptors in READFDS and WRITEFDS. */
struct serial *scbs[MAXIMUM_WAIT_OBJECTS];
/* The number of valid entries in SCBS. */
size_t num_scbs;
int fd;
int num_ready;
size_t indx;
num_ready = 0;
num_handles = 0;
num_scbs = 0;
for (fd = 0; fd < n; ++fd)
{
HANDLE read = NULL, except = NULL;
struct serial *scb;
/* There is no support yet for WRITEFDS. At present, this isn't
used by GDB -- but we do not want to silently ignore WRITEFDS
if something starts using it. */
gdb_assert (!writefds || !FD_ISSET (fd, writefds));
if ((!readfds || !FD_ISSET (fd, readfds))
&& (!exceptfds || !FD_ISSET (fd, exceptfds)))
continue;
scb = serial_for_fd (fd);
if (scb)
{
serial_wait_handle (scb, &read, &except);
scbs[num_scbs++] = scb;
}
if (read == NULL)
read = (HANDLE) _get_osfhandle (fd);
if (except == NULL)
{
if (!never_handle)
never_handle = CreateEvent (0, FALSE, FALSE, 0);
except = never_handle;
}
if (readfds && FD_ISSET (fd, readfds))
{
gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
handles[num_handles++] = read;
}
if (exceptfds && FD_ISSET (fd, exceptfds))
{
gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
handles[num_handles++] = except;
}
}
gdb_assert (num_handles < MAXIMUM_WAIT_OBJECTS);
handles[num_handles++] = sigint_event;
event = WaitForMultipleObjects (num_handles,
handles,
FALSE,
timeout
? (timeout->tv_sec * 1000
+ timeout->tv_usec / 1000)
: INFINITE);
/* EVENT can only be a value in the WAIT_ABANDONED_0 range if the
HANDLES included an abandoned mutex. Since GDB doesn't use
mutexes, that should never occur. */
gdb_assert (!(WAIT_ABANDONED_0 <= event
&& event < WAIT_ABANDONED_0 + num_handles));
/* We no longer need the helper threads to check for activity. */
for (indx = 0; indx < num_scbs; ++indx)
serial_done_wait_handle (scbs[indx]);
if (event == WAIT_FAILED)
return -1;
if (event == WAIT_TIMEOUT)
return 0;
/* Run through the READFDS, clearing bits corresponding to descriptors
for which input is unavailable. */
h = handles[event - WAIT_OBJECT_0];
for (fd = 0, indx = 0; fd < n; ++fd)
{
HANDLE fd_h;
if ((!readfds || !FD_ISSET (fd, readfds))
&& (!exceptfds || !FD_ISSET (fd, exceptfds)))
continue;
if (readfds && FD_ISSET (fd, readfds))
{
fd_h = handles[indx++];
/* This handle might be ready, even though it wasn't the handle
returned by WaitForMultipleObjects. */
if (fd_h != h && WaitForSingleObject (fd_h, 0) != WAIT_OBJECT_0)
FD_CLR (fd, readfds);
else
num_ready++;
}
if (exceptfds && FD_ISSET (fd, exceptfds))
{
fd_h = handles[indx++];
/* This handle might be ready, even though it wasn't the handle
returned by WaitForMultipleObjects. */
if (fd_h != h && WaitForSingleObject (fd_h, 0) != WAIT_OBJECT_0)
FD_CLR (fd, exceptfds);
else
num_ready++;
}
}
/* With multi-threaded SIGINT handling, there is a race between the
readline signal handler and GDB. It may still be in
rl_prep_terminal in another thread. Do not return until it is
done; we can check the state here because we never longjmp from
signal handlers on Windows. */
while (RL_ISSTATE (RL_STATE_SIGHANDLER))
Sleep (1);
if (h == sigint_event
|| WaitForSingleObject (sigint_event, 0) == WAIT_OBJECT_0)
{
if (sigint_handler != NULL)
call_async_signal_handler (sigint_handler);
if (num_ready == 0)
{
errno = EINTR;
return -1;
}
}
return num_ready;
}
/* Wrapper for the body of signal handlers. On Windows systems, a
SIGINT handler runs in its own thread. We can't longjmp from
there, and we shouldn't even prompt the user. Delay HANDLER
until the main thread is next in gdb_select. */
void
gdb_call_async_signal_handler (struct async_signal_handler *handler,
int immediate_p)
{
if (immediate_p)
sigint_handler = handler;
else
{
mark_async_signal_handler (handler);
sigint_handler = NULL;
}
SetEvent (sigint_event);
}
/* -Wmissing-prototypes */
extern initialize_file_ftype _initialize_mingw_hdep;
void
_initialize_mingw_hdep (void)
{
sigint_event = CreateEvent (0, FALSE, FALSE, 0);
}
|
