quorum: Avoid bdrv_aio_writev() for rewrites
[qemu.git] / io / channel-watch.c
1 /*
2 * QEMU I/O channels watch helper APIs
3 *
4 * Copyright (c) 2015 Red Hat, Inc.
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21 #include "qemu/osdep.h"
22 #include "io/channel-watch.h"
23
24 typedef struct QIOChannelFDSource QIOChannelFDSource;
25 struct QIOChannelFDSource {
26 GSource parent;
27 GPollFD fd;
28 QIOChannel *ioc;
29 GIOCondition condition;
30 };
31
32
33 #ifdef CONFIG_WIN32
34 typedef struct QIOChannelSocketSource QIOChannelSocketSource;
35 struct QIOChannelSocketSource {
36 GSource parent;
37 GPollFD fd;
38 QIOChannel *ioc;
39 SOCKET socket;
40 int revents;
41 GIOCondition condition;
42 };
43
44 #endif
45
46
47 typedef struct QIOChannelFDPairSource QIOChannelFDPairSource;
48 struct QIOChannelFDPairSource {
49 GSource parent;
50 GPollFD fdread;
51 GPollFD fdwrite;
52 QIOChannel *ioc;
53 GIOCondition condition;
54 };
55
56
57 static gboolean
58 qio_channel_fd_source_prepare(GSource *source G_GNUC_UNUSED,
59 gint *timeout)
60 {
61 *timeout = -1;
62
63 return FALSE;
64 }
65
66
67 static gboolean
68 qio_channel_fd_source_check(GSource *source)
69 {
70 QIOChannelFDSource *ssource = (QIOChannelFDSource *)source;
71
72 return ssource->fd.revents & ssource->condition;
73 }
74
75
76 static gboolean
77 qio_channel_fd_source_dispatch(GSource *source,
78 GSourceFunc callback,
79 gpointer user_data)
80 {
81 QIOChannelFunc func = (QIOChannelFunc)callback;
82 QIOChannelFDSource *ssource = (QIOChannelFDSource *)source;
83
84 return (*func)(ssource->ioc,
85 ssource->fd.revents & ssource->condition,
86 user_data);
87 }
88
89
90 static void
91 qio_channel_fd_source_finalize(GSource *source)
92 {
93 QIOChannelFDSource *ssource = (QIOChannelFDSource *)source;
94
95 object_unref(OBJECT(ssource->ioc));
96 }
97
98
99 #ifdef CONFIG_WIN32
100 static gboolean
101 qio_channel_socket_source_prepare(GSource *source G_GNUC_UNUSED,
102 gint *timeout)
103 {
104 *timeout = -1;
105
106 return FALSE;
107 }
108
109
110 /*
111 * NB, this impl only works when the socket is in non-blocking
112 * mode on Win32
113 */
114 static gboolean
115 qio_channel_socket_source_check(GSource *source)
116 {
117 static struct timeval tv0;
118
119 QIOChannelSocketSource *ssource = (QIOChannelSocketSource *)source;
120 WSANETWORKEVENTS ev;
121 fd_set rfds, wfds, xfds;
122
123 if (!ssource->condition) {
124 return 0;
125 }
126
127 WSAEnumNetworkEvents(ssource->socket, ssource->ioc->event, &ev);
128
129 FD_ZERO(&rfds);
130 FD_ZERO(&wfds);
131 FD_ZERO(&xfds);
132 if (ssource->condition & G_IO_IN) {
133 FD_SET((SOCKET)ssource->socket, &rfds);
134 }
135 if (ssource->condition & G_IO_OUT) {
136 FD_SET((SOCKET)ssource->socket, &wfds);
137 }
138 if (ssource->condition & G_IO_PRI) {
139 FD_SET((SOCKET)ssource->socket, &xfds);
140 }
141 ssource->revents = 0;
142 if (select(0, &rfds, &wfds, &xfds, &tv0) == 0) {
143 return 0;
144 }
145
146 if (FD_ISSET(ssource->socket, &rfds)) {
147 ssource->revents |= G_IO_IN;
148 }
149 if (FD_ISSET(ssource->socket, &wfds)) {
150 ssource->revents |= G_IO_OUT;
151 }
152 if (FD_ISSET(ssource->socket, &xfds)) {
153 ssource->revents |= G_IO_PRI;
154 }
155
156 return ssource->revents;
157 }
158
159
160 static gboolean
161 qio_channel_socket_source_dispatch(GSource *source,
162 GSourceFunc callback,
163 gpointer user_data)
164 {
165 QIOChannelFunc func = (QIOChannelFunc)callback;
166 QIOChannelSocketSource *ssource = (QIOChannelSocketSource *)source;
167
168 return (*func)(ssource->ioc, ssource->revents, user_data);
169 }
170
171
172 static void
173 qio_channel_socket_source_finalize(GSource *source)
174 {
175 QIOChannelSocketSource *ssource = (QIOChannelSocketSource *)source;
176
177 object_unref(OBJECT(ssource->ioc));
178 }
179
180
181 GSourceFuncs qio_channel_socket_source_funcs = {
182 qio_channel_socket_source_prepare,
183 qio_channel_socket_source_check,
184 qio_channel_socket_source_dispatch,
185 qio_channel_socket_source_finalize
186 };
187 #endif
188
189
190 static gboolean
191 qio_channel_fd_pair_source_prepare(GSource *source G_GNUC_UNUSED,
192 gint *timeout)
193 {
194 *timeout = -1;
195
196 return FALSE;
197 }
198
199
200 static gboolean
201 qio_channel_fd_pair_source_check(GSource *source)
202 {
203 QIOChannelFDPairSource *ssource = (QIOChannelFDPairSource *)source;
204 GIOCondition poll_condition = ssource->fdread.revents |
205 ssource->fdwrite.revents;
206
207 return poll_condition & ssource->condition;
208 }
209
210
211 static gboolean
212 qio_channel_fd_pair_source_dispatch(GSource *source,
213 GSourceFunc callback,
214 gpointer user_data)
215 {
216 QIOChannelFunc func = (QIOChannelFunc)callback;
217 QIOChannelFDPairSource *ssource = (QIOChannelFDPairSource *)source;
218 GIOCondition poll_condition = ssource->fdread.revents |
219 ssource->fdwrite.revents;
220
221 return (*func)(ssource->ioc,
222 poll_condition & ssource->condition,
223 user_data);
224 }
225
226
227 static void
228 qio_channel_fd_pair_source_finalize(GSource *source)
229 {
230 QIOChannelFDPairSource *ssource = (QIOChannelFDPairSource *)source;
231
232 object_unref(OBJECT(ssource->ioc));
233 }
234
235
236 GSourceFuncs qio_channel_fd_source_funcs = {
237 qio_channel_fd_source_prepare,
238 qio_channel_fd_source_check,
239 qio_channel_fd_source_dispatch,
240 qio_channel_fd_source_finalize
241 };
242
243
244 GSourceFuncs qio_channel_fd_pair_source_funcs = {
245 qio_channel_fd_pair_source_prepare,
246 qio_channel_fd_pair_source_check,
247 qio_channel_fd_pair_source_dispatch,
248 qio_channel_fd_pair_source_finalize
249 };
250
251
252 GSource *qio_channel_create_fd_watch(QIOChannel *ioc,
253 int fd,
254 GIOCondition condition)
255 {
256 GSource *source;
257 QIOChannelFDSource *ssource;
258
259 source = g_source_new(&qio_channel_fd_source_funcs,
260 sizeof(QIOChannelFDSource));
261 ssource = (QIOChannelFDSource *)source;
262
263 ssource->ioc = ioc;
264 object_ref(OBJECT(ioc));
265
266 ssource->condition = condition;
267
268 #ifdef CONFIG_WIN32
269 ssource->fd.fd = (gint64)_get_osfhandle(fd);
270 #else
271 ssource->fd.fd = fd;
272 #endif
273 ssource->fd.events = condition;
274
275 g_source_add_poll(source, &ssource->fd);
276
277 return source;
278 }
279
280 #ifdef CONFIG_WIN32
281 GSource *qio_channel_create_socket_watch(QIOChannel *ioc,
282 int socket,
283 GIOCondition condition)
284 {
285 GSource *source;
286 QIOChannelSocketSource *ssource;
287
288 source = g_source_new(&qio_channel_socket_source_funcs,
289 sizeof(QIOChannelSocketSource));
290 ssource = (QIOChannelSocketSource *)source;
291
292 ssource->ioc = ioc;
293 object_ref(OBJECT(ioc));
294
295 ssource->condition = condition;
296 ssource->socket = socket;
297 ssource->revents = 0;
298
299 ssource->fd.fd = (gintptr)ioc->event;
300 ssource->fd.events = G_IO_IN;
301
302 g_source_add_poll(source, &ssource->fd);
303
304 return source;
305 }
306 #else
307 GSource *qio_channel_create_socket_watch(QIOChannel *ioc,
308 int socket,
309 GIOCondition condition)
310 {
311 return qio_channel_create_fd_watch(ioc, socket, condition);
312 }
313 #endif
314
315 GSource *qio_channel_create_fd_pair_watch(QIOChannel *ioc,
316 int fdread,
317 int fdwrite,
318 GIOCondition condition)
319 {
320 GSource *source;
321 QIOChannelFDPairSource *ssource;
322
323 source = g_source_new(&qio_channel_fd_pair_source_funcs,
324 sizeof(QIOChannelFDPairSource));
325 ssource = (QIOChannelFDPairSource *)source;
326
327 ssource->ioc = ioc;
328 object_ref(OBJECT(ioc));
329
330 ssource->condition = condition;
331
332 #ifdef CONFIG_WIN32
333 ssource->fdread.fd = (gint64)_get_osfhandle(fdread);
334 ssource->fdwrite.fd = (gint64)_get_osfhandle(fdwrite);
335 #else
336 ssource->fdread.fd = fdread;
337 ssource->fdwrite.fd = fdwrite;
338 #endif
339
340 ssource->fdread.events = condition & G_IO_IN;
341 ssource->fdwrite.events = condition & G_IO_OUT;
342
343 g_source_add_poll(source, &ssource->fdread);
344 g_source_add_poll(source, &ssource->fdwrite);
345
346 return source;
347 }