xref: /qemu/chardev/char.c (revision 18375b5c)
1 /*
2  * QEMU System Emulator
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "qemu/osdep.h"
25 #include "qemu/cutils.h"
26 #include "monitor/monitor.h"
27 #include "sysemu/sysemu.h"
28 #include "qemu/config-file.h"
29 #include "qemu/error-report.h"
30 #include "chardev/char.h"
31 #include "qmp-commands.h"
32 #include "qapi-visit.h"
33 #include "sysemu/replay.h"
34 #include "qemu/help_option.h"
35 
36 #include "chardev/char-mux.h"
37 
38 /***********************************************************/
39 /* character device */
40 
41 static Object *get_chardevs_root(void)
42 {
43     return container_get(object_get_root(), "/chardevs");
44 }
45 
46 void qemu_chr_be_event(Chardev *s, int event)
47 {
48     CharBackend *be = s->be;
49 
50     /* Keep track if the char device is open */
51     switch (event) {
52         case CHR_EVENT_OPENED:
53             s->be_open = 1;
54             break;
55         case CHR_EVENT_CLOSED:
56             s->be_open = 0;
57             break;
58     }
59 
60     if (!be || !be->chr_event) {
61         return;
62     }
63 
64     be->chr_event(be->opaque, event);
65 }
66 
67 /* Not reporting errors from writing to logfile, as logs are
68  * defined to be "best effort" only */
69 static void qemu_chr_write_log(Chardev *s, const uint8_t *buf, size_t len)
70 {
71     size_t done = 0;
72     ssize_t ret;
73 
74     if (s->logfd < 0) {
75         return;
76     }
77 
78     while (done < len) {
79     retry:
80         ret = write(s->logfd, buf + done, len - done);
81         if (ret == -1 && errno == EAGAIN) {
82             g_usleep(100);
83             goto retry;
84         }
85 
86         if (ret <= 0) {
87             return;
88         }
89         done += ret;
90     }
91 }
92 
93 static int qemu_chr_write_buffer(Chardev *s,
94                                  const uint8_t *buf, int len,
95                                  int *offset, bool write_all)
96 {
97     ChardevClass *cc = CHARDEV_GET_CLASS(s);
98     int res = 0;
99     *offset = 0;
100 
101     qemu_mutex_lock(&s->chr_write_lock);
102     while (*offset < len) {
103     retry:
104         res = cc->chr_write(s, buf + *offset, len - *offset);
105         if (res < 0 && errno == EAGAIN && write_all) {
106             g_usleep(100);
107             goto retry;
108         }
109 
110         if (res <= 0) {
111             break;
112         }
113 
114         *offset += res;
115         if (!write_all) {
116             break;
117         }
118     }
119     if (*offset > 0) {
120         qemu_chr_write_log(s, buf, *offset);
121     }
122     qemu_mutex_unlock(&s->chr_write_lock);
123 
124     return res;
125 }
126 
127 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all)
128 {
129     int offset = 0;
130     int res;
131 
132     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_PLAY) {
133         replay_char_write_event_load(&res, &offset);
134         assert(offset <= len);
135         qemu_chr_write_buffer(s, buf, offset, &offset, true);
136         return res;
137     }
138 
139     res = qemu_chr_write_buffer(s, buf, len, &offset, write_all);
140 
141     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
142         replay_char_write_event_save(res, offset);
143     }
144 
145     if (res < 0) {
146         return res;
147     }
148     return offset;
149 }
150 
151 int qemu_chr_be_can_write(Chardev *s)
152 {
153     CharBackend *be = s->be;
154 
155     if (!be || !be->chr_can_read) {
156         return 0;
157     }
158 
159     return be->chr_can_read(be->opaque);
160 }
161 
162 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len)
163 {
164     CharBackend *be = s->be;
165 
166     if (be && be->chr_read) {
167         be->chr_read(be->opaque, buf, len);
168     }
169 }
170 
171 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len)
172 {
173     if (qemu_chr_replay(s)) {
174         if (replay_mode == REPLAY_MODE_PLAY) {
175             return;
176         }
177         replay_chr_be_write(s, buf, len);
178     } else {
179         qemu_chr_be_write_impl(s, buf, len);
180     }
181 }
182 
183 int qemu_chr_add_client(Chardev *s, int fd)
184 {
185     return CHARDEV_GET_CLASS(s)->chr_add_client ?
186         CHARDEV_GET_CLASS(s)->chr_add_client(s, fd) : -1;
187 }
188 
189 static void qemu_char_open(Chardev *chr, ChardevBackend *backend,
190                            bool *be_opened, Error **errp)
191 {
192     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
193     /* Any ChardevCommon member would work */
194     ChardevCommon *common = backend ? backend->u.null.data : NULL;
195 
196     if (common && common->has_logfile) {
197         int flags = O_WRONLY | O_CREAT;
198         if (common->has_logappend &&
199             common->logappend) {
200             flags |= O_APPEND;
201         } else {
202             flags |= O_TRUNC;
203         }
204         chr->logfd = qemu_open(common->logfile, flags, 0666);
205         if (chr->logfd < 0) {
206             error_setg_errno(errp, errno,
207                              "Unable to open logfile %s",
208                              common->logfile);
209             return;
210         }
211     }
212 
213     if (cc->open) {
214         cc->open(chr, backend, be_opened, errp);
215     }
216 }
217 
218 static void char_init(Object *obj)
219 {
220     Chardev *chr = CHARDEV(obj);
221 
222     chr->logfd = -1;
223     qemu_mutex_init(&chr->chr_write_lock);
224 }
225 
226 static int null_chr_write(Chardev *chr, const uint8_t *buf, int len)
227 {
228     return len;
229 }
230 
231 static void char_class_init(ObjectClass *oc, void *data)
232 {
233     ChardevClass *cc = CHARDEV_CLASS(oc);
234 
235     cc->chr_write = null_chr_write;
236 }
237 
238 static void char_finalize(Object *obj)
239 {
240     Chardev *chr = CHARDEV(obj);
241 
242     if (chr->be) {
243         chr->be->chr = NULL;
244     }
245     g_free(chr->filename);
246     g_free(chr->label);
247     if (chr->logfd != -1) {
248         close(chr->logfd);
249     }
250     qemu_mutex_destroy(&chr->chr_write_lock);
251 }
252 
253 static const TypeInfo char_type_info = {
254     .name = TYPE_CHARDEV,
255     .parent = TYPE_OBJECT,
256     .instance_size = sizeof(Chardev),
257     .instance_init = char_init,
258     .instance_finalize = char_finalize,
259     .abstract = true,
260     .class_size = sizeof(ChardevClass),
261     .class_init = char_class_init,
262 };
263 
264 /**
265  * Called after processing of default and command-line-specified
266  * chardevs to deliver CHR_EVENT_OPENED events to any FEs attached
267  * to a mux chardev. This is done here to ensure that
268  * output/prompts/banners are only displayed for the FE that has
269  * focus when initial command-line processing/machine init is
270  * completed.
271  *
272  * After this point, any new FE attached to any new or existing
273  * mux will receive CHR_EVENT_OPENED notifications for the BE
274  * immediately.
275  */
276 static int open_muxes(Object *child, void *opaque)
277 {
278     if (CHARDEV_IS_MUX(child)) {
279         /* send OPENED to all already-attached FEs */
280         mux_chr_send_all_event(CHARDEV(child), CHR_EVENT_OPENED);
281         /* mark mux as OPENED so any new FEs will immediately receive
282          * OPENED event
283          */
284         qemu_chr_be_event(CHARDEV(child), CHR_EVENT_OPENED);
285     }
286 
287     return 0;
288 }
289 
290 static void muxes_realize_done(Notifier *notifier, void *unused)
291 {
292     muxes_realized = true;
293     object_child_foreach(get_chardevs_root(), open_muxes, NULL);
294 }
295 
296 static Notifier muxes_realize_notify = {
297     .notify = muxes_realize_done,
298 };
299 
300 static bool qemu_chr_is_busy(Chardev *s)
301 {
302     if (CHARDEV_IS_MUX(s)) {
303         MuxChardev *d = MUX_CHARDEV(s);
304         return d->mux_cnt >= 0;
305     } else {
306         return s->be != NULL;
307     }
308 }
309 
310 int qemu_chr_wait_connected(Chardev *chr, Error **errp)
311 {
312     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
313 
314     if (cc->chr_wait_connected) {
315         return cc->chr_wait_connected(chr, errp);
316     }
317 
318     return 0;
319 }
320 
321 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename)
322 {
323     char host[65], port[33], width[8], height[8];
324     int pos;
325     const char *p;
326     QemuOpts *opts;
327     Error *local_err = NULL;
328 
329     opts = qemu_opts_create(qemu_find_opts("chardev"), label, 1, &local_err);
330     if (local_err) {
331         error_report_err(local_err);
332         return NULL;
333     }
334 
335     if (strstart(filename, "mon:", &p)) {
336         filename = p;
337         qemu_opt_set(opts, "mux", "on", &error_abort);
338         if (strcmp(filename, "stdio") == 0) {
339             /* Monitor is muxed to stdio: do not exit on Ctrl+C by default
340              * but pass it to the guest.  Handle this only for compat syntax,
341              * for -chardev syntax we have special option for this.
342              * This is what -nographic did, redirecting+muxing serial+monitor
343              * to stdio causing Ctrl+C to be passed to guest. */
344             qemu_opt_set(opts, "signal", "off", &error_abort);
345         }
346     }
347 
348     if (strcmp(filename, "null")    == 0 ||
349         strcmp(filename, "pty")     == 0 ||
350         strcmp(filename, "msmouse") == 0 ||
351         strcmp(filename, "wctablet") == 0 ||
352         strcmp(filename, "braille") == 0 ||
353         strcmp(filename, "testdev") == 0 ||
354         strcmp(filename, "stdio")   == 0) {
355         qemu_opt_set(opts, "backend", filename, &error_abort);
356         return opts;
357     }
358     if (strstart(filename, "vc", &p)) {
359         qemu_opt_set(opts, "backend", "vc", &error_abort);
360         if (*p == ':') {
361             if (sscanf(p+1, "%7[0-9]x%7[0-9]", width, height) == 2) {
362                 /* pixels */
363                 qemu_opt_set(opts, "width", width, &error_abort);
364                 qemu_opt_set(opts, "height", height, &error_abort);
365             } else if (sscanf(p+1, "%7[0-9]Cx%7[0-9]C", width, height) == 2) {
366                 /* chars */
367                 qemu_opt_set(opts, "cols", width, &error_abort);
368                 qemu_opt_set(opts, "rows", height, &error_abort);
369             } else {
370                 goto fail;
371             }
372         }
373         return opts;
374     }
375     if (strcmp(filename, "con:") == 0) {
376         qemu_opt_set(opts, "backend", "console", &error_abort);
377         return opts;
378     }
379     if (strstart(filename, "COM", NULL)) {
380         qemu_opt_set(opts, "backend", "serial", &error_abort);
381         qemu_opt_set(opts, "path", filename, &error_abort);
382         return opts;
383     }
384     if (strstart(filename, "file:", &p)) {
385         qemu_opt_set(opts, "backend", "file", &error_abort);
386         qemu_opt_set(opts, "path", p, &error_abort);
387         return opts;
388     }
389     if (strstart(filename, "pipe:", &p)) {
390         qemu_opt_set(opts, "backend", "pipe", &error_abort);
391         qemu_opt_set(opts, "path", p, &error_abort);
392         return opts;
393     }
394     if (strstart(filename, "tcp:", &p) ||
395         strstart(filename, "telnet:", &p) ||
396         strstart(filename, "tn3270:", &p)) {
397         if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
398             host[0] = 0;
399             if (sscanf(p, ":%32[^,]%n", port, &pos) < 1)
400                 goto fail;
401         }
402         qemu_opt_set(opts, "backend", "socket", &error_abort);
403         qemu_opt_set(opts, "host", host, &error_abort);
404         qemu_opt_set(opts, "port", port, &error_abort);
405         if (p[pos] == ',') {
406             qemu_opts_do_parse(opts, p+pos+1, NULL, &local_err);
407             if (local_err) {
408                 error_report_err(local_err);
409                 goto fail;
410             }
411         }
412         if (strstart(filename, "telnet:", &p)) {
413             qemu_opt_set(opts, "telnet", "on", &error_abort);
414         } else if (strstart(filename, "tn3270:", &p)) {
415             qemu_opt_set(opts, "tn3270", "on", &error_abort);
416         }
417         return opts;
418     }
419     if (strstart(filename, "udp:", &p)) {
420         qemu_opt_set(opts, "backend", "udp", &error_abort);
421         if (sscanf(p, "%64[^:]:%32[^@,]%n", host, port, &pos) < 2) {
422             host[0] = 0;
423             if (sscanf(p, ":%32[^@,]%n", port, &pos) < 1) {
424                 goto fail;
425             }
426         }
427         qemu_opt_set(opts, "host", host, &error_abort);
428         qemu_opt_set(opts, "port", port, &error_abort);
429         if (p[pos] == '@') {
430             p += pos + 1;
431             if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
432                 host[0] = 0;
433                 if (sscanf(p, ":%32[^,]%n", port, &pos) < 1) {
434                     goto fail;
435                 }
436             }
437             qemu_opt_set(opts, "localaddr", host, &error_abort);
438             qemu_opt_set(opts, "localport", port, &error_abort);
439         }
440         return opts;
441     }
442     if (strstart(filename, "unix:", &p)) {
443         qemu_opt_set(opts, "backend", "socket", &error_abort);
444         qemu_opts_do_parse(opts, p, "path", &local_err);
445         if (local_err) {
446             error_report_err(local_err);
447             goto fail;
448         }
449         return opts;
450     }
451     if (strstart(filename, "/dev/parport", NULL) ||
452         strstart(filename, "/dev/ppi", NULL)) {
453         qemu_opt_set(opts, "backend", "parallel", &error_abort);
454         qemu_opt_set(opts, "path", filename, &error_abort);
455         return opts;
456     }
457     if (strstart(filename, "/dev/", NULL)) {
458         qemu_opt_set(opts, "backend", "serial", &error_abort);
459         qemu_opt_set(opts, "path", filename, &error_abort);
460         return opts;
461     }
462 
463 fail:
464     qemu_opts_del(opts);
465     return NULL;
466 }
467 
468 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend)
469 {
470     const char *logfile = qemu_opt_get(opts, "logfile");
471 
472     backend->has_logfile = logfile != NULL;
473     backend->logfile = g_strdup(logfile);
474 
475     backend->has_logappend = true;
476     backend->logappend = qemu_opt_get_bool(opts, "logappend", false);
477 }
478 
479 static const ChardevClass *char_get_class(const char *driver, Error **errp)
480 {
481     ObjectClass *oc;
482     const ChardevClass *cc;
483     char *typename = g_strdup_printf("chardev-%s", driver);
484 
485     oc = object_class_by_name(typename);
486     g_free(typename);
487 
488     if (!object_class_dynamic_cast(oc, TYPE_CHARDEV)) {
489         error_setg(errp, "'%s' is not a valid char driver name", driver);
490         return NULL;
491     }
492 
493     if (object_class_is_abstract(oc)) {
494         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "driver",
495                    "abstract device type");
496         return NULL;
497     }
498 
499     cc = CHARDEV_CLASS(oc);
500     if (cc->internal) {
501         error_setg(errp, "'%s' is not a valid char driver name", driver);
502         return NULL;
503     }
504 
505     return cc;
506 }
507 
508 static const struct ChardevAlias {
509     const char *typename;
510     const char *alias;
511 } chardev_alias_table[] = {
512 #ifdef HAVE_CHARDEV_PARPORT
513     { "parallel", "parport" },
514 #endif
515 #ifdef HAVE_CHARDEV_SERIAL
516     { "serial", "tty" },
517 #endif
518 };
519 
520 typedef struct ChadevClassFE {
521     void (*fn)(const char *name, void *opaque);
522     void *opaque;
523 } ChadevClassFE;
524 
525 static void
526 chardev_class_foreach(ObjectClass *klass, void *opaque)
527 {
528     ChadevClassFE *fe = opaque;
529 
530     assert(g_str_has_prefix(object_class_get_name(klass), "chardev-"));
531     if (CHARDEV_CLASS(klass)->internal) {
532         return;
533     }
534 
535     fe->fn(object_class_get_name(klass) + 8, fe->opaque);
536 }
537 
538 static void
539 chardev_name_foreach(void (*fn)(const char *name, void *opaque), void *opaque)
540 {
541     ChadevClassFE fe = { .fn = fn, .opaque = opaque };
542     int i;
543 
544     object_class_foreach(chardev_class_foreach, TYPE_CHARDEV, false, &fe);
545 
546     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
547         fn(chardev_alias_table[i].alias, opaque);
548     }
549 }
550 
551 static void
552 help_string_append(const char *name, void *opaque)
553 {
554     GString *str = opaque;
555 
556     g_string_append_printf(str, "\n%s", name);
557 }
558 
559 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
560                                 Error **errp)
561 {
562     Error *local_err = NULL;
563     const ChardevClass *cc;
564     Chardev *chr;
565     int i;
566     ChardevBackend *backend = NULL;
567     const char *name = qemu_opt_get(opts, "backend");
568     const char *id = qemu_opts_id(opts);
569     char *bid = NULL;
570 
571     if (name == NULL) {
572         error_setg(errp, "chardev: \"%s\" missing backend",
573                    qemu_opts_id(opts));
574         return NULL;
575     }
576 
577     if (is_help_option(name)) {
578         GString *str = g_string_new("");
579 
580         chardev_name_foreach(help_string_append, str);
581 
582         error_report("Available chardev backend types: %s", str->str);
583         g_string_free(str, true);
584         exit(0);
585     }
586 
587     if (id == NULL) {
588         error_setg(errp, "chardev: no id specified");
589         return NULL;
590     }
591 
592     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
593         if (g_strcmp0(chardev_alias_table[i].alias, name) == 0) {
594             name = chardev_alias_table[i].typename;
595             break;
596         }
597     }
598 
599     cc = char_get_class(name, errp);
600     if (cc == NULL) {
601         return NULL;
602     }
603 
604     backend = g_new0(ChardevBackend, 1);
605     backend->type = CHARDEV_BACKEND_KIND_NULL;
606 
607     if (qemu_opt_get_bool(opts, "mux", 0)) {
608         bid = g_strdup_printf("%s-base", id);
609     }
610 
611     chr = NULL;
612     if (cc->parse) {
613         cc->parse(opts, backend, &local_err);
614         if (local_err) {
615             error_propagate(errp, local_err);
616             goto out;
617         }
618     } else {
619         ChardevCommon *ccom = g_new0(ChardevCommon, 1);
620         qemu_chr_parse_common(opts, ccom);
621         backend->u.null.data = ccom; /* Any ChardevCommon member would work */
622     }
623 
624     chr = qemu_chardev_new(bid ? bid : id,
625                            object_class_get_name(OBJECT_CLASS(cc)),
626                            backend, errp);
627 
628     if (chr == NULL) {
629         goto out;
630     }
631 
632     if (bid) {
633         Chardev *mux;
634         qapi_free_ChardevBackend(backend);
635         backend = g_new0(ChardevBackend, 1);
636         backend->type = CHARDEV_BACKEND_KIND_MUX;
637         backend->u.mux.data = g_new0(ChardevMux, 1);
638         backend->u.mux.data->chardev = g_strdup(bid);
639         mux = qemu_chardev_new(id, TYPE_CHARDEV_MUX, backend, errp);
640         if (mux == NULL) {
641             object_unparent(OBJECT(chr));
642             chr = NULL;
643             goto out;
644         }
645         chr = mux;
646     }
647 
648 out:
649     qapi_free_ChardevBackend(backend);
650     g_free(bid);
651     return chr;
652 }
653 
654 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename)
655 {
656     const char *p;
657     Chardev *chr;
658     QemuOpts *opts;
659     Error *err = NULL;
660 
661     if (strstart(filename, "chardev:", &p)) {
662         return qemu_chr_find(p);
663     }
664 
665     opts = qemu_chr_parse_compat(label, filename);
666     if (!opts)
667         return NULL;
668 
669     chr = qemu_chr_new_from_opts(opts, &err);
670     if (err) {
671         error_report_err(err);
672     }
673     if (chr && qemu_opt_get_bool(opts, "mux", 0)) {
674         monitor_init(chr, MONITOR_USE_READLINE);
675     }
676     qemu_opts_del(opts);
677     return chr;
678 }
679 
680 Chardev *qemu_chr_new(const char *label, const char *filename)
681 {
682     Chardev *chr;
683     chr = qemu_chr_new_noreplay(label, filename);
684     if (chr) {
685         if (replay_mode != REPLAY_MODE_NONE) {
686             qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_REPLAY);
687         }
688         if (qemu_chr_replay(chr) && CHARDEV_GET_CLASS(chr)->chr_ioctl) {
689             error_report("Replay: ioctl is not supported "
690                          "for serial devices yet");
691         }
692         replay_register_char_driver(chr);
693     }
694     return chr;
695 }
696 
697 static int qmp_query_chardev_foreach(Object *obj, void *data)
698 {
699     Chardev *chr = CHARDEV(obj);
700     ChardevInfoList **list = data;
701     ChardevInfoList *info = g_malloc0(sizeof(*info));
702 
703     info->value = g_malloc0(sizeof(*info->value));
704     info->value->label = g_strdup(chr->label);
705     info->value->filename = g_strdup(chr->filename);
706     info->value->frontend_open = chr->be && chr->be->fe_open;
707 
708     info->next = *list;
709     *list = info;
710 
711     return 0;
712 }
713 
714 ChardevInfoList *qmp_query_chardev(Error **errp)
715 {
716     ChardevInfoList *chr_list = NULL;
717 
718     object_child_foreach(get_chardevs_root(),
719                          qmp_query_chardev_foreach, &chr_list);
720 
721     return chr_list;
722 }
723 
724 static void
725 qmp_prepend_backend(const char *name, void *opaque)
726 {
727     ChardevBackendInfoList **list = opaque;
728     ChardevBackendInfoList *info = g_malloc0(sizeof(*info));
729 
730     info->value = g_malloc0(sizeof(*info->value));
731     info->value->name = g_strdup(name);
732     info->next = *list;
733     *list = info;
734 }
735 
736 ChardevBackendInfoList *qmp_query_chardev_backends(Error **errp)
737 {
738     ChardevBackendInfoList *backend_list = NULL;
739 
740     chardev_name_foreach(qmp_prepend_backend, &backend_list);
741 
742     return backend_list;
743 }
744 
745 Chardev *qemu_chr_find(const char *name)
746 {
747     Object *obj = object_resolve_path_component(get_chardevs_root(), name);
748 
749     return obj ? CHARDEV(obj) : NULL;
750 }
751 
752 QemuOptsList qemu_chardev_opts = {
753     .name = "chardev",
754     .implied_opt_name = "backend",
755     .head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
756     .desc = {
757         {
758             .name = "backend",
759             .type = QEMU_OPT_STRING,
760         },{
761             .name = "path",
762             .type = QEMU_OPT_STRING,
763         },{
764             .name = "host",
765             .type = QEMU_OPT_STRING,
766         },{
767             .name = "port",
768             .type = QEMU_OPT_STRING,
769         },{
770             .name = "localaddr",
771             .type = QEMU_OPT_STRING,
772         },{
773             .name = "localport",
774             .type = QEMU_OPT_STRING,
775         },{
776             .name = "to",
777             .type = QEMU_OPT_NUMBER,
778         },{
779             .name = "ipv4",
780             .type = QEMU_OPT_BOOL,
781         },{
782             .name = "ipv6",
783             .type = QEMU_OPT_BOOL,
784         },{
785             .name = "wait",
786             .type = QEMU_OPT_BOOL,
787         },{
788             .name = "server",
789             .type = QEMU_OPT_BOOL,
790         },{
791             .name = "delay",
792             .type = QEMU_OPT_BOOL,
793         },{
794             .name = "reconnect",
795             .type = QEMU_OPT_NUMBER,
796         },{
797             .name = "telnet",
798             .type = QEMU_OPT_BOOL,
799         },{
800             .name = "tn3270",
801             .type = QEMU_OPT_BOOL,
802         },{
803             .name = "tls-creds",
804             .type = QEMU_OPT_STRING,
805         },{
806             .name = "width",
807             .type = QEMU_OPT_NUMBER,
808         },{
809             .name = "height",
810             .type = QEMU_OPT_NUMBER,
811         },{
812             .name = "cols",
813             .type = QEMU_OPT_NUMBER,
814         },{
815             .name = "rows",
816             .type = QEMU_OPT_NUMBER,
817         },{
818             .name = "mux",
819             .type = QEMU_OPT_BOOL,
820         },{
821             .name = "signal",
822             .type = QEMU_OPT_BOOL,
823         },{
824             .name = "name",
825             .type = QEMU_OPT_STRING,
826         },{
827             .name = "debug",
828             .type = QEMU_OPT_NUMBER,
829         },{
830             .name = "size",
831             .type = QEMU_OPT_SIZE,
832         },{
833             .name = "chardev",
834             .type = QEMU_OPT_STRING,
835         },{
836             .name = "append",
837             .type = QEMU_OPT_BOOL,
838         },{
839             .name = "logfile",
840             .type = QEMU_OPT_STRING,
841         },{
842             .name = "logappend",
843             .type = QEMU_OPT_BOOL,
844         },
845         { /* end of list */ }
846     },
847 };
848 
849 bool qemu_chr_has_feature(Chardev *chr,
850                           ChardevFeature feature)
851 {
852     return test_bit(feature, chr->features);
853 }
854 
855 void qemu_chr_set_feature(Chardev *chr,
856                            ChardevFeature feature)
857 {
858     return set_bit(feature, chr->features);
859 }
860 
861 Chardev *qemu_chardev_new(const char *id, const char *typename,
862                           ChardevBackend *backend,
863                           Error **errp)
864 {
865     Object *obj;
866     Chardev *chr = NULL;
867     Error *local_err = NULL;
868     bool be_opened = true;
869 
870     assert(g_str_has_prefix(typename, "chardev-"));
871 
872     obj = object_new(typename);
873     chr = CHARDEV(obj);
874     chr->label = g_strdup(id);
875 
876     qemu_char_open(chr, backend, &be_opened, &local_err);
877     if (local_err) {
878         goto end;
879     }
880 
881     if (!chr->filename) {
882         chr->filename = g_strdup(typename + 8);
883     }
884     if (be_opened) {
885         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
886     }
887 
888     if (id) {
889         object_property_add_child(get_chardevs_root(), id, obj, &local_err);
890         if (local_err) {
891             goto end;
892         }
893         object_unref(obj);
894     }
895 
896 end:
897     if (local_err) {
898         error_propagate(errp, local_err);
899         object_unref(obj);
900         return NULL;
901     }
902 
903     return chr;
904 }
905 
906 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
907                                Error **errp)
908 {
909     const ChardevClass *cc;
910     ChardevReturn *ret;
911     Chardev *chr;
912 
913     cc = char_get_class(ChardevBackendKind_lookup[backend->type], errp);
914     if (!cc) {
915         return NULL;
916     }
917 
918     chr = qemu_chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
919                            backend, errp);
920     if (!chr) {
921         return NULL;
922     }
923 
924     ret = g_new0(ChardevReturn, 1);
925     if (CHARDEV_IS_PTY(chr)) {
926         ret->pty = g_strdup(chr->filename + 4);
927         ret->has_pty = true;
928     }
929 
930     return ret;
931 }
932 
933 void qmp_chardev_remove(const char *id, Error **errp)
934 {
935     Chardev *chr;
936 
937     chr = qemu_chr_find(id);
938     if (chr == NULL) {
939         error_setg(errp, "Chardev '%s' not found", id);
940         return;
941     }
942     if (qemu_chr_is_busy(chr)) {
943         error_setg(errp, "Chardev '%s' is busy", id);
944         return;
945     }
946     if (qemu_chr_replay(chr)) {
947         error_setg(errp,
948             "Chardev '%s' cannot be unplugged in record/replay mode", id);
949         return;
950     }
951     object_unparent(OBJECT(chr));
952 }
953 
954 void qmp_chardev_send_break(const char *id, Error **errp)
955 {
956     Chardev *chr;
957 
958     chr = qemu_chr_find(id);
959     if (chr == NULL) {
960         error_setg(errp, "Chardev '%s' not found", id);
961         return;
962     }
963     qemu_chr_be_event(chr, CHR_EVENT_BREAK);
964 }
965 
966 void qemu_chr_cleanup(void)
967 {
968     object_unparent(get_chardevs_root());
969 }
970 
971 static void register_types(void)
972 {
973     type_register_static(&char_type_info);
974 
975     /* this must be done after machine init, since we register FEs with muxes
976      * as part of realize functions like serial_isa_realizefn when -nographic
977      * is specified
978      */
979     qemu_add_machine_init_done_notifier(&muxes_realize_notify);
980 }
981 
982 type_init(register_types);
983