1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21#include "qemu/osdep.h"
22#include "io/channel.h"
23#include "qapi/error.h"
24#include "qemu/main-loop.h"
25#include "qemu/iov.h"
26
27bool qio_channel_has_feature(QIOChannel *ioc,
28 QIOChannelFeature feature)
29{
30 return ioc->features & (1 << feature);
31}
32
33
34void qio_channel_set_feature(QIOChannel *ioc,
35 QIOChannelFeature feature)
36{
37 ioc->features |= (1 << feature);
38}
39
40
41void qio_channel_set_name(QIOChannel *ioc,
42 const char *name)
43{
44 g_free(ioc->name);
45 ioc->name = g_strdup(name);
46}
47
48
49ssize_t qio_channel_readv_full(QIOChannel *ioc,
50 const struct iovec *iov,
51 size_t niov,
52 int **fds,
53 size_t *nfds,
54 Error **errp)
55{
56 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
57
58 if ((fds || nfds) &&
59 !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
60 error_setg_errno(errp, EINVAL,
61 "Channel does not support file descriptor passing");
62 return -1;
63 }
64
65 return klass->io_readv(ioc, iov, niov, fds, nfds, errp);
66}
67
68
69ssize_t qio_channel_writev_full(QIOChannel *ioc,
70 const struct iovec *iov,
71 size_t niov,
72 int *fds,
73 size_t nfds,
74 Error **errp)
75{
76 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
77
78 if ((fds || nfds) &&
79 !qio_channel_has_feature(ioc, QIO_CHANNEL_FEATURE_FD_PASS)) {
80 error_setg_errno(errp, EINVAL,
81 "Channel does not support file descriptor passing");
82 return -1;
83 }
84
85 return klass->io_writev(ioc, iov, niov, fds, nfds, errp);
86}
87
88
89int qio_channel_readv_all_eof(QIOChannel *ioc,
90 const struct iovec *iov,
91 size_t niov,
92 Error **errp)
93{
94 int ret = -1;
95 struct iovec *local_iov = g_new(struct iovec, niov);
96 struct iovec *local_iov_head = local_iov;
97 unsigned int nlocal_iov = niov;
98 bool partial = false;
99
100 nlocal_iov = iov_copy(local_iov, nlocal_iov,
101 iov, niov,
102 0, iov_size(iov, niov));
103
104 while (nlocal_iov > 0) {
105 ssize_t len;
106 len = qio_channel_readv(ioc, local_iov, nlocal_iov, errp);
107 if (len == QIO_CHANNEL_ERR_BLOCK) {
108 if (qemu_in_coroutine()) {
109 qio_channel_yield(ioc, G_IO_IN);
110 } else {
111 qio_channel_wait(ioc, G_IO_IN);
112 }
113 continue;
114 } else if (len < 0) {
115 goto cleanup;
116 } else if (len == 0) {
117 if (partial) {
118 error_setg(errp,
119 "Unexpected end-of-file before all bytes were read");
120 } else {
121 ret = 0;
122 }
123 goto cleanup;
124 }
125
126 partial = true;
127 iov_discard_front(&local_iov, &nlocal_iov, len);
128 }
129
130 ret = 1;
131
132 cleanup:
133 g_free(local_iov_head);
134 return ret;
135}
136
137int qio_channel_readv_all(QIOChannel *ioc,
138 const struct iovec *iov,
139 size_t niov,
140 Error **errp)
141{
142 int ret = qio_channel_readv_all_eof(ioc, iov, niov, errp);
143
144 if (ret == 0) {
145 ret = -1;
146 error_setg(errp,
147 "Unexpected end-of-file before all bytes were read");
148 } else if (ret == 1) {
149 ret = 0;
150 }
151 return ret;
152}
153
154int qio_channel_writev_all(QIOChannel *ioc,
155 const struct iovec *iov,
156 size_t niov,
157 Error **errp)
158{
159 int ret = -1;
160 struct iovec *local_iov = g_new(struct iovec, niov);
161 struct iovec *local_iov_head = local_iov;
162 unsigned int nlocal_iov = niov;
163
164 nlocal_iov = iov_copy(local_iov, nlocal_iov,
165 iov, niov,
166 0, iov_size(iov, niov));
167
168 while (nlocal_iov > 0) {
169 ssize_t len;
170 len = qio_channel_writev(ioc, local_iov, nlocal_iov, errp);
171 if (len == QIO_CHANNEL_ERR_BLOCK) {
172 if (qemu_in_coroutine()) {
173 qio_channel_yield(ioc, G_IO_OUT);
174 } else {
175 qio_channel_wait(ioc, G_IO_OUT);
176 }
177 continue;
178 }
179 if (len < 0) {
180 goto cleanup;
181 }
182
183 iov_discard_front(&local_iov, &nlocal_iov, len);
184 }
185
186 ret = 0;
187 cleanup:
188 g_free(local_iov_head);
189 return ret;
190}
191
192ssize_t qio_channel_readv(QIOChannel *ioc,
193 const struct iovec *iov,
194 size_t niov,
195 Error **errp)
196{
197 return qio_channel_readv_full(ioc, iov, niov, NULL, NULL, errp);
198}
199
200
201ssize_t qio_channel_writev(QIOChannel *ioc,
202 const struct iovec *iov,
203 size_t niov,
204 Error **errp)
205{
206 return qio_channel_writev_full(ioc, iov, niov, NULL, 0, errp);
207}
208
209
210ssize_t qio_channel_read(QIOChannel *ioc,
211 char *buf,
212 size_t buflen,
213 Error **errp)
214{
215 struct iovec iov = { .iov_base = buf, .iov_len = buflen };
216 return qio_channel_readv_full(ioc, &iov, 1, NULL, NULL, errp);
217}
218
219
220ssize_t qio_channel_write(QIOChannel *ioc,
221 const char *buf,
222 size_t buflen,
223 Error **errp)
224{
225 struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
226 return qio_channel_writev_full(ioc, &iov, 1, NULL, 0, errp);
227}
228
229
230int qio_channel_read_all_eof(QIOChannel *ioc,
231 char *buf,
232 size_t buflen,
233 Error **errp)
234{
235 struct iovec iov = { .iov_base = buf, .iov_len = buflen };
236 return qio_channel_readv_all_eof(ioc, &iov, 1, errp);
237}
238
239
240int qio_channel_read_all(QIOChannel *ioc,
241 char *buf,
242 size_t buflen,
243 Error **errp)
244{
245 struct iovec iov = { .iov_base = buf, .iov_len = buflen };
246 return qio_channel_readv_all(ioc, &iov, 1, errp);
247}
248
249
250int qio_channel_write_all(QIOChannel *ioc,
251 const char *buf,
252 size_t buflen,
253 Error **errp)
254{
255 struct iovec iov = { .iov_base = (char *)buf, .iov_len = buflen };
256 return qio_channel_writev_all(ioc, &iov, 1, errp);
257}
258
259
260int qio_channel_set_blocking(QIOChannel *ioc,
261 bool enabled,
262 Error **errp)
263{
264 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
265 return klass->io_set_blocking(ioc, enabled, errp);
266}
267
268
269int qio_channel_close(QIOChannel *ioc,
270 Error **errp)
271{
272 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
273 return klass->io_close(ioc, errp);
274}
275
276
277GSource *qio_channel_create_watch(QIOChannel *ioc,
278 GIOCondition condition)
279{
280 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
281 GSource *ret = klass->io_create_watch(ioc, condition);
282
283 if (ioc->name) {
284 g_source_set_name(ret, ioc->name);
285 }
286
287 return ret;
288}
289
290
291void qio_channel_set_aio_fd_handler(QIOChannel *ioc,
292 AioContext *ctx,
293 IOHandler *io_read,
294 IOHandler *io_write,
295 void *opaque)
296{
297 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
298
299 klass->io_set_aio_fd_handler(ioc, ctx, io_read, io_write, opaque);
300}
301
302guint qio_channel_add_watch_full(QIOChannel *ioc,
303 GIOCondition condition,
304 QIOChannelFunc func,
305 gpointer user_data,
306 GDestroyNotify notify,
307 GMainContext *context)
308{
309 GSource *source;
310 guint id;
311
312 source = qio_channel_create_watch(ioc, condition);
313
314 g_source_set_callback(source, (GSourceFunc)func, user_data, notify);
315
316 id = g_source_attach(source, context);
317 g_source_unref(source);
318
319 return id;
320}
321
322guint qio_channel_add_watch(QIOChannel *ioc,
323 GIOCondition condition,
324 QIOChannelFunc func,
325 gpointer user_data,
326 GDestroyNotify notify)
327{
328 return qio_channel_add_watch_full(ioc, condition, func,
329 user_data, notify, NULL);
330}
331
332GSource *qio_channel_add_watch_source(QIOChannel *ioc,
333 GIOCondition condition,
334 QIOChannelFunc func,
335 gpointer user_data,
336 GDestroyNotify notify,
337 GMainContext *context)
338{
339 GSource *source;
340 guint id;
341
342 id = qio_channel_add_watch_full(ioc, condition, func,
343 user_data, notify, context);
344 source = g_main_context_find_source_by_id(context, id);
345 g_source_ref(source);
346 return source;
347}
348
349
350int qio_channel_shutdown(QIOChannel *ioc,
351 QIOChannelShutdown how,
352 Error **errp)
353{
354 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
355
356 if (!klass->io_shutdown) {
357 error_setg(errp, "Data path shutdown not supported");
358 return -1;
359 }
360
361 return klass->io_shutdown(ioc, how, errp);
362}
363
364
365void qio_channel_set_delay(QIOChannel *ioc,
366 bool enabled)
367{
368 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
369
370 if (klass->io_set_delay) {
371 klass->io_set_delay(ioc, enabled);
372 }
373}
374
375
376void qio_channel_set_cork(QIOChannel *ioc,
377 bool enabled)
378{
379 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
380
381 if (klass->io_set_cork) {
382 klass->io_set_cork(ioc, enabled);
383 }
384}
385
386
387off_t qio_channel_io_seek(QIOChannel *ioc,
388 off_t offset,
389 int whence,
390 Error **errp)
391{
392 QIOChannelClass *klass = QIO_CHANNEL_GET_CLASS(ioc);
393
394 if (!klass->io_seek) {
395 error_setg(errp, "Channel does not support random access");
396 return -1;
397 }
398
399 return klass->io_seek(ioc, offset, whence, errp);
400}
401
402
403static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc);
404
405static void qio_channel_restart_read(void *opaque)
406{
407 QIOChannel *ioc = opaque;
408 Coroutine *co = ioc->read_coroutine;
409
410 ioc->read_coroutine = NULL;
411 qio_channel_set_aio_fd_handlers(ioc);
412 aio_co_wake(co);
413}
414
415static void qio_channel_restart_write(void *opaque)
416{
417 QIOChannel *ioc = opaque;
418 Coroutine *co = ioc->write_coroutine;
419
420 ioc->write_coroutine = NULL;
421 qio_channel_set_aio_fd_handlers(ioc);
422 aio_co_wake(co);
423}
424
425static void qio_channel_set_aio_fd_handlers(QIOChannel *ioc)
426{
427 IOHandler *rd_handler = NULL, *wr_handler = NULL;
428 AioContext *ctx;
429
430 if (ioc->read_coroutine) {
431 rd_handler = qio_channel_restart_read;
432 }
433 if (ioc->write_coroutine) {
434 wr_handler = qio_channel_restart_write;
435 }
436
437 ctx = ioc->ctx ? ioc->ctx : iohandler_get_aio_context();
438 qio_channel_set_aio_fd_handler(ioc, ctx, rd_handler, wr_handler, ioc);
439}
440
441void qio_channel_attach_aio_context(QIOChannel *ioc,
442 AioContext *ctx)
443{
444 assert(!ioc->read_coroutine);
445 assert(!ioc->write_coroutine);
446 ioc->ctx = ctx;
447}
448
449void qio_channel_detach_aio_context(QIOChannel *ioc)
450{
451 ioc->read_coroutine = NULL;
452 ioc->write_coroutine = NULL;
453 qio_channel_set_aio_fd_handlers(ioc);
454 ioc->ctx = NULL;
455}
456
457void coroutine_fn qio_channel_yield(QIOChannel *ioc,
458 GIOCondition condition)
459{
460 assert(qemu_in_coroutine());
461 if (condition == G_IO_IN) {
462 assert(!ioc->read_coroutine);
463 ioc->read_coroutine = qemu_coroutine_self();
464 } else if (condition == G_IO_OUT) {
465 assert(!ioc->write_coroutine);
466 ioc->write_coroutine = qemu_coroutine_self();
467 } else {
468 abort();
469 }
470 qio_channel_set_aio_fd_handlers(ioc);
471 qemu_coroutine_yield();
472}
473
474
475static gboolean qio_channel_wait_complete(QIOChannel *ioc,
476 GIOCondition condition,
477 gpointer opaque)
478{
479 GMainLoop *loop = opaque;
480
481 g_main_loop_quit(loop);
482 return FALSE;
483}
484
485
486void qio_channel_wait(QIOChannel *ioc,
487 GIOCondition condition)
488{
489 GMainContext *ctxt = g_main_context_new();
490 GMainLoop *loop = g_main_loop_new(ctxt, TRUE);
491 GSource *source;
492
493 source = qio_channel_create_watch(ioc, condition);
494
495 g_source_set_callback(source,
496 (GSourceFunc)qio_channel_wait_complete,
497 loop,
498 NULL);
499
500 g_source_attach(source, ctxt);
501
502 g_main_loop_run(loop);
503
504 g_source_unref(source);
505 g_main_loop_unref(loop);
506 g_main_context_unref(ctxt);
507}
508
509
510static void qio_channel_finalize(Object *obj)
511{
512 QIOChannel *ioc = QIO_CHANNEL(obj);
513
514 g_free(ioc->name);
515
516#ifdef _WIN32
517 if (ioc->event) {
518 CloseHandle(ioc->event);
519 }
520#endif
521}
522
523static const TypeInfo qio_channel_info = {
524 .parent = TYPE_OBJECT,
525 .name = TYPE_QIO_CHANNEL,
526 .instance_size = sizeof(QIOChannel),
527 .instance_finalize = qio_channel_finalize,
528 .abstract = true,
529 .class_size = sizeof(QIOChannelClass),
530};
531
532
533static void qio_channel_register_types(void)
534{
535 type_register_static(&qio_channel_info);
536}
537
538
539type_init(qio_channel_register_types);
540