xref: /openbmc/qemu/chardev/char.c (revision 5690b437)
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 
25 #include "qemu/osdep.h"
26 #include "qemu/cutils.h"
27 #include "monitor/monitor.h"
28 #include "qemu/config-file.h"
29 #include "qemu/error-report.h"
30 #include "qemu/qemu-print.h"
31 #include "chardev/char.h"
32 #include "qapi/error.h"
33 #include "qapi/qapi-commands-char.h"
34 #include "qapi/qmp/qerror.h"
35 #include "sysemu/replay.h"
36 #include "qemu/help_option.h"
37 #include "qemu/module.h"
38 #include "qemu/option.h"
39 #include "qemu/id.h"
40 #include "qemu/coroutine.h"
41 #include "qemu/yank.h"
42 
43 #include "chardev-internal.h"
44 
45 /***********************************************************/
46 /* character device */
47 
48 Object *get_chardevs_root(void)
49 {
50     return container_get(object_get_root(), "/chardevs");
51 }
52 
53 static void chr_be_event(Chardev *s, QEMUChrEvent event)
54 {
55     CharBackend *be = s->be;
56 
57     if (!be || !be->chr_event) {
58         return;
59     }
60 
61     be->chr_event(be->opaque, event);
62 }
63 
64 void qemu_chr_be_event(Chardev *s, QEMUChrEvent event)
65 {
66     /* Keep track if the char device is open */
67     switch (event) {
68         case CHR_EVENT_OPENED:
69             s->be_open = 1;
70             break;
71         case CHR_EVENT_CLOSED:
72             s->be_open = 0;
73             break;
74     case CHR_EVENT_BREAK:
75     case CHR_EVENT_MUX_IN:
76     case CHR_EVENT_MUX_OUT:
77         /* Ignore */
78         break;
79     }
80 
81     CHARDEV_GET_CLASS(s)->chr_be_event(s, event);
82 }
83 
84 /* Not reporting errors from writing to logfile, as logs are
85  * defined to be "best effort" only */
86 static void qemu_chr_write_log(Chardev *s, const uint8_t *buf, size_t len)
87 {
88     size_t done = 0;
89     ssize_t ret;
90 
91     if (s->logfd < 0) {
92         return;
93     }
94 
95     while (done < len) {
96     retry:
97         ret = write(s->logfd, buf + done, len - done);
98         if (ret == -1 && errno == EAGAIN) {
99             g_usleep(100);
100             goto retry;
101         }
102 
103         if (ret <= 0) {
104             return;
105         }
106         done += ret;
107     }
108 }
109 
110 static int qemu_chr_write_buffer(Chardev *s,
111                                  const uint8_t *buf, int len,
112                                  int *offset, bool write_all)
113 {
114     ChardevClass *cc = CHARDEV_GET_CLASS(s);
115     int res = 0;
116     *offset = 0;
117 
118     qemu_mutex_lock(&s->chr_write_lock);
119     while (*offset < len) {
120     retry:
121         res = cc->chr_write(s, buf + *offset, len - *offset);
122         if (res < 0 && errno == EAGAIN && write_all) {
123             if (qemu_in_coroutine()) {
124                 qemu_co_sleep_ns(QEMU_CLOCK_REALTIME, 100000);
125             } else {
126                 g_usleep(100);
127             }
128             goto retry;
129         }
130 
131         if (res <= 0) {
132             break;
133         }
134 
135         *offset += res;
136         if (!write_all) {
137             break;
138         }
139     }
140     if (*offset > 0) {
141         /*
142          * If some data was written by backend, we should
143          * only log what was actually written. This method
144          * may be invoked again to write the remaining
145          * method, thus we'll log the remainder at that time.
146          */
147         qemu_chr_write_log(s, buf, *offset);
148     } else if (res < 0) {
149         /*
150          * If a fatal error was reported by the backend,
151          * assume this method won't be invoked again with
152          * this buffer, so log it all right away.
153          */
154         qemu_chr_write_log(s, buf, len);
155     }
156     qemu_mutex_unlock(&s->chr_write_lock);
157 
158     return res;
159 }
160 
161 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all)
162 {
163     int offset = 0;
164     int res;
165 
166     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_PLAY) {
167         replay_char_write_event_load(&res, &offset);
168         assert(offset <= len);
169         qemu_chr_write_buffer(s, buf, offset, &offset, true);
170         return res;
171     }
172 
173     res = qemu_chr_write_buffer(s, buf, len, &offset, write_all);
174 
175     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
176         replay_char_write_event_save(res, offset);
177     }
178 
179     if (res < 0) {
180         return res;
181     }
182     return offset;
183 }
184 
185 int qemu_chr_be_can_write(Chardev *s)
186 {
187     CharBackend *be = s->be;
188 
189     if (!be || !be->chr_can_read) {
190         return 0;
191     }
192 
193     return be->chr_can_read(be->opaque);
194 }
195 
196 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len)
197 {
198     CharBackend *be = s->be;
199 
200     if (be && be->chr_read) {
201         be->chr_read(be->opaque, buf, len);
202     }
203 }
204 
205 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len)
206 {
207     if (qemu_chr_replay(s)) {
208         if (replay_mode == REPLAY_MODE_PLAY) {
209             return;
210         }
211         replay_chr_be_write(s, buf, len);
212     } else {
213         qemu_chr_be_write_impl(s, buf, len);
214     }
215 }
216 
217 void qemu_chr_be_update_read_handlers(Chardev *s,
218                                       GMainContext *context)
219 {
220     ChardevClass *cc = CHARDEV_GET_CLASS(s);
221 
222     assert(qemu_chr_has_feature(s, QEMU_CHAR_FEATURE_GCONTEXT)
223            || !context);
224     s->gcontext = context;
225     if (cc->chr_update_read_handler) {
226         cc->chr_update_read_handler(s);
227     }
228 }
229 
230 int qemu_chr_add_client(Chardev *s, int fd)
231 {
232     return CHARDEV_GET_CLASS(s)->chr_add_client ?
233         CHARDEV_GET_CLASS(s)->chr_add_client(s, fd) : -1;
234 }
235 
236 static void qemu_char_open(Chardev *chr, ChardevBackend *backend,
237                            bool *be_opened, Error **errp)
238 {
239     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
240     /* Any ChardevCommon member would work */
241     ChardevCommon *common = backend ? backend->u.null.data : NULL;
242 
243     if (common && common->has_logfile) {
244         int flags = O_WRONLY;
245         if (common->has_logappend &&
246             common->logappend) {
247             flags |= O_APPEND;
248         } else {
249             flags |= O_TRUNC;
250         }
251         chr->logfd = qemu_create(common->logfile, flags, 0666, errp);
252         if (chr->logfd < 0) {
253             return;
254         }
255     }
256 
257     if (cc->open) {
258         cc->open(chr, backend, be_opened, errp);
259     }
260 }
261 
262 static void char_init(Object *obj)
263 {
264     Chardev *chr = CHARDEV(obj);
265 
266     chr->handover_yank_instance = false;
267     chr->logfd = -1;
268     qemu_mutex_init(&chr->chr_write_lock);
269 
270     /*
271      * Assume if chr_update_read_handler is implemented it will
272      * take the updated gcontext into account.
273      */
274     if (CHARDEV_GET_CLASS(chr)->chr_update_read_handler) {
275         qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT);
276     }
277 
278 }
279 
280 static int null_chr_write(Chardev *chr, const uint8_t *buf, int len)
281 {
282     return len;
283 }
284 
285 static void char_class_init(ObjectClass *oc, void *data)
286 {
287     ChardevClass *cc = CHARDEV_CLASS(oc);
288 
289     cc->chr_write = null_chr_write;
290     cc->chr_be_event = chr_be_event;
291 }
292 
293 static void char_finalize(Object *obj)
294 {
295     Chardev *chr = CHARDEV(obj);
296 
297     if (chr->be) {
298         chr->be->chr = NULL;
299     }
300     g_free(chr->filename);
301     g_free(chr->label);
302     if (chr->logfd != -1) {
303         close(chr->logfd);
304     }
305     qemu_mutex_destroy(&chr->chr_write_lock);
306 }
307 
308 static const TypeInfo char_type_info = {
309     .name = TYPE_CHARDEV,
310     .parent = TYPE_OBJECT,
311     .instance_size = sizeof(Chardev),
312     .instance_init = char_init,
313     .instance_finalize = char_finalize,
314     .abstract = true,
315     .class_size = sizeof(ChardevClass),
316     .class_init = char_class_init,
317 };
318 
319 static bool qemu_chr_is_busy(Chardev *s)
320 {
321     if (CHARDEV_IS_MUX(s)) {
322         MuxChardev *d = MUX_CHARDEV(s);
323         return d->mux_cnt >= 0;
324     } else {
325         return s->be != NULL;
326     }
327 }
328 
329 int qemu_chr_wait_connected(Chardev *chr, Error **errp)
330 {
331     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
332 
333     if (cc->chr_wait_connected) {
334         return cc->chr_wait_connected(chr, errp);
335     }
336 
337     return 0;
338 }
339 
340 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename,
341                                 bool permit_mux_mon)
342 {
343     char host[65], port[33], width[8], height[8];
344     int pos;
345     const char *p;
346     QemuOpts *opts;
347     Error *local_err = NULL;
348 
349     opts = qemu_opts_create(qemu_find_opts("chardev"), label, 1, &local_err);
350     if (local_err) {
351         error_report_err(local_err);
352         return NULL;
353     }
354 
355     if (strstart(filename, "mon:", &p)) {
356         if (!permit_mux_mon) {
357             error_report("mon: isn't supported in this context");
358             return NULL;
359         }
360         filename = p;
361         qemu_opt_set(opts, "mux", "on", &error_abort);
362         if (strcmp(filename, "stdio") == 0) {
363             /* Monitor is muxed to stdio: do not exit on Ctrl+C by default
364              * but pass it to the guest.  Handle this only for compat syntax,
365              * for -chardev syntax we have special option for this.
366              * This is what -nographic did, redirecting+muxing serial+monitor
367              * to stdio causing Ctrl+C to be passed to guest. */
368             qemu_opt_set(opts, "signal", "off", &error_abort);
369         }
370     }
371 
372     if (strcmp(filename, "null")    == 0 ||
373         strcmp(filename, "pty")     == 0 ||
374         strcmp(filename, "msmouse") == 0 ||
375         strcmp(filename, "wctablet") == 0 ||
376         strcmp(filename, "braille") == 0 ||
377         strcmp(filename, "testdev") == 0 ||
378         strcmp(filename, "stdio")   == 0) {
379         qemu_opt_set(opts, "backend", filename, &error_abort);
380         return opts;
381     }
382     if (strstart(filename, "vc", &p)) {
383         qemu_opt_set(opts, "backend", "vc", &error_abort);
384         if (*p == ':') {
385             if (sscanf(p+1, "%7[0-9]x%7[0-9]", width, height) == 2) {
386                 /* pixels */
387                 qemu_opt_set(opts, "width", width, &error_abort);
388                 qemu_opt_set(opts, "height", height, &error_abort);
389             } else if (sscanf(p+1, "%7[0-9]Cx%7[0-9]C", width, height) == 2) {
390                 /* chars */
391                 qemu_opt_set(opts, "cols", width, &error_abort);
392                 qemu_opt_set(opts, "rows", height, &error_abort);
393             } else {
394                 goto fail;
395             }
396         }
397         return opts;
398     }
399     if (strcmp(filename, "con:") == 0) {
400         qemu_opt_set(opts, "backend", "console", &error_abort);
401         return opts;
402     }
403     if (strstart(filename, "COM", NULL)) {
404         qemu_opt_set(opts, "backend", "serial", &error_abort);
405         qemu_opt_set(opts, "path", filename, &error_abort);
406         return opts;
407     }
408     if (strstart(filename, "file:", &p)) {
409         qemu_opt_set(opts, "backend", "file", &error_abort);
410         qemu_opt_set(opts, "path", p, &error_abort);
411         return opts;
412     }
413     if (strstart(filename, "pipe:", &p)) {
414         qemu_opt_set(opts, "backend", "pipe", &error_abort);
415         qemu_opt_set(opts, "path", p, &error_abort);
416         return opts;
417     }
418     if (strstart(filename, "tcp:", &p) ||
419         strstart(filename, "telnet:", &p) ||
420         strstart(filename, "tn3270:", &p) ||
421         strstart(filename, "websocket:", &p)) {
422         if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
423             host[0] = 0;
424             if (sscanf(p, ":%32[^,]%n", port, &pos) < 1)
425                 goto fail;
426         }
427         qemu_opt_set(opts, "backend", "socket", &error_abort);
428         qemu_opt_set(opts, "host", host, &error_abort);
429         qemu_opt_set(opts, "port", port, &error_abort);
430         if (p[pos] == ',') {
431             if (!qemu_opts_do_parse(opts, p + pos + 1, NULL, &local_err)) {
432                 error_report_err(local_err);
433                 goto fail;
434             }
435         }
436         if (strstart(filename, "telnet:", &p)) {
437             qemu_opt_set(opts, "telnet", "on", &error_abort);
438         } else if (strstart(filename, "tn3270:", &p)) {
439             qemu_opt_set(opts, "tn3270", "on", &error_abort);
440         } else if (strstart(filename, "websocket:", &p)) {
441             qemu_opt_set(opts, "websocket", "on", &error_abort);
442         }
443         return opts;
444     }
445     if (strstart(filename, "udp:", &p)) {
446         qemu_opt_set(opts, "backend", "udp", &error_abort);
447         if (sscanf(p, "%64[^:]:%32[^@,]%n", host, port, &pos) < 2) {
448             host[0] = 0;
449             if (sscanf(p, ":%32[^@,]%n", port, &pos) < 1) {
450                 goto fail;
451             }
452         }
453         qemu_opt_set(opts, "host", host, &error_abort);
454         qemu_opt_set(opts, "port", port, &error_abort);
455         if (p[pos] == '@') {
456             p += pos + 1;
457             if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
458                 host[0] = 0;
459                 if (sscanf(p, ":%32[^,]%n", port, &pos) < 1) {
460                     goto fail;
461                 }
462             }
463             qemu_opt_set(opts, "localaddr", host, &error_abort);
464             qemu_opt_set(opts, "localport", port, &error_abort);
465         }
466         return opts;
467     }
468     if (strstart(filename, "unix:", &p)) {
469         qemu_opt_set(opts, "backend", "socket", &error_abort);
470         if (!qemu_opts_do_parse(opts, p, "path", &local_err)) {
471             error_report_err(local_err);
472             goto fail;
473         }
474         return opts;
475     }
476     if (strstart(filename, "/dev/parport", NULL) ||
477         strstart(filename, "/dev/ppi", NULL)) {
478         qemu_opt_set(opts, "backend", "parallel", &error_abort);
479         qemu_opt_set(opts, "path", filename, &error_abort);
480         return opts;
481     }
482     if (strstart(filename, "/dev/", NULL)) {
483         qemu_opt_set(opts, "backend", "serial", &error_abort);
484         qemu_opt_set(opts, "path", filename, &error_abort);
485         return opts;
486     }
487 
488     error_report("'%s' is not a valid char driver", filename);
489 
490 fail:
491     qemu_opts_del(opts);
492     return NULL;
493 }
494 
495 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend)
496 {
497     const char *logfile = qemu_opt_get(opts, "logfile");
498 
499     backend->has_logfile = logfile != NULL;
500     backend->logfile = g_strdup(logfile);
501 
502     backend->has_logappend = true;
503     backend->logappend = qemu_opt_get_bool(opts, "logappend", false);
504 }
505 
506 static const ChardevClass *char_get_class(const char *driver, Error **errp)
507 {
508     ObjectClass *oc;
509     const ChardevClass *cc;
510     char *typename = g_strdup_printf("chardev-%s", driver);
511 
512     oc = module_object_class_by_name(typename);
513     g_free(typename);
514 
515     if (!object_class_dynamic_cast(oc, TYPE_CHARDEV)) {
516         error_setg(errp, "'%s' is not a valid char driver name", driver);
517         return NULL;
518     }
519 
520     if (object_class_is_abstract(oc)) {
521         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "driver",
522                    "an abstract device type");
523         return NULL;
524     }
525 
526     cc = CHARDEV_CLASS(oc);
527     if (cc->internal) {
528         error_setg(errp, "'%s' is not a valid char driver name", driver);
529         return NULL;
530     }
531 
532     return cc;
533 }
534 
535 static struct ChardevAlias {
536     const char *typename;
537     const char *alias;
538     bool deprecation_warning_printed;
539 } chardev_alias_table[] = {
540 #ifdef HAVE_CHARDEV_PARPORT
541     { "parallel", "parport" },
542 #endif
543 #ifdef HAVE_CHARDEV_SERIAL
544     { "serial", "tty" },
545 #endif
546 };
547 
548 typedef struct ChadevClassFE {
549     void (*fn)(const char *name, void *opaque);
550     void *opaque;
551 } ChadevClassFE;
552 
553 static void
554 chardev_class_foreach(ObjectClass *klass, void *opaque)
555 {
556     ChadevClassFE *fe = opaque;
557 
558     assert(g_str_has_prefix(object_class_get_name(klass), "chardev-"));
559     if (CHARDEV_CLASS(klass)->internal) {
560         return;
561     }
562 
563     fe->fn(object_class_get_name(klass) + 8, fe->opaque);
564 }
565 
566 static void
567 chardev_name_foreach(void (*fn)(const char *name, void *opaque),
568                      void *opaque)
569 {
570     ChadevClassFE fe = { .fn = fn, .opaque = opaque };
571 
572     object_class_foreach(chardev_class_foreach, TYPE_CHARDEV, false, &fe);
573 }
574 
575 static void
576 help_string_append(const char *name, void *opaque)
577 {
578     GString *str = opaque;
579 
580     g_string_append_printf(str, "\n  %s", name);
581 }
582 
583 static const char *chardev_alias_translate(const char *name)
584 {
585     int i;
586     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
587         if (g_strcmp0(chardev_alias_table[i].alias, name) == 0) {
588             if (!chardev_alias_table[i].deprecation_warning_printed) {
589                 warn_report("The alias '%s' is deprecated, use '%s' instead",
590                             name, chardev_alias_table[i].typename);
591                 chardev_alias_table[i].deprecation_warning_printed = true;
592             }
593             return chardev_alias_table[i].typename;
594         }
595     }
596     return name;
597 }
598 
599 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts, Error **errp)
600 {
601     Error *local_err = NULL;
602     const ChardevClass *cc;
603     ChardevBackend *backend = NULL;
604     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
605 
606     if (name == NULL) {
607         error_setg(errp, "chardev: \"%s\" missing backend",
608                    qemu_opts_id(opts));
609         return NULL;
610     }
611 
612     cc = char_get_class(name, errp);
613     if (cc == NULL) {
614         return NULL;
615     }
616 
617     backend = g_new0(ChardevBackend, 1);
618     backend->type = CHARDEV_BACKEND_KIND_NULL;
619 
620     if (cc->parse) {
621         cc->parse(opts, backend, &local_err);
622         if (local_err) {
623             error_propagate(errp, local_err);
624             qapi_free_ChardevBackend(backend);
625             return NULL;
626         }
627     } else {
628         ChardevCommon *ccom = g_new0(ChardevCommon, 1);
629         qemu_chr_parse_common(opts, ccom);
630         backend->u.null.data = ccom; /* Any ChardevCommon member would work */
631     }
632 
633     return backend;
634 }
635 
636 Chardev *qemu_chr_new_from_opts(QemuOpts *opts, GMainContext *context,
637                                 Error **errp)
638 {
639     const ChardevClass *cc;
640     Chardev *chr = NULL;
641     ChardevBackend *backend = NULL;
642     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
643     const char *id = qemu_opts_id(opts);
644     char *bid = NULL;
645 
646     if (name && is_help_option(name)) {
647         GString *str = g_string_new("");
648 
649         chardev_name_foreach(help_string_append, str);
650 
651         qemu_printf("Available chardev backend types: %s\n", str->str);
652         g_string_free(str, true);
653         return NULL;
654     }
655 
656     if (id == NULL) {
657         error_setg(errp, "chardev: no id specified");
658         return NULL;
659     }
660 
661     backend = qemu_chr_parse_opts(opts, errp);
662     if (backend == NULL) {
663         return NULL;
664     }
665 
666     cc = char_get_class(name, errp);
667     if (cc == NULL) {
668         goto out;
669     }
670 
671     if (qemu_opt_get_bool(opts, "mux", 0)) {
672         bid = g_strdup_printf("%s-base", id);
673     }
674 
675     chr = qemu_chardev_new(bid ? bid : id,
676                            object_class_get_name(OBJECT_CLASS(cc)),
677                            backend, context, errp);
678 
679     if (chr == NULL) {
680         goto out;
681     }
682 
683     if (bid) {
684         Chardev *mux;
685         qapi_free_ChardevBackend(backend);
686         backend = g_new0(ChardevBackend, 1);
687         backend->type = CHARDEV_BACKEND_KIND_MUX;
688         backend->u.mux.data = g_new0(ChardevMux, 1);
689         backend->u.mux.data->chardev = g_strdup(bid);
690         mux = qemu_chardev_new(id, TYPE_CHARDEV_MUX, backend, context, errp);
691         if (mux == NULL) {
692             object_unparent(OBJECT(chr));
693             chr = NULL;
694             goto out;
695         }
696         chr = mux;
697     }
698 
699 out:
700     qapi_free_ChardevBackend(backend);
701     g_free(bid);
702     return chr;
703 }
704 
705 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
706                                bool permit_mux_mon, GMainContext *context)
707 {
708     const char *p;
709     Chardev *chr;
710     QemuOpts *opts;
711     Error *err = NULL;
712 
713     if (strstart(filename, "chardev:", &p)) {
714         return qemu_chr_find(p);
715     }
716 
717     opts = qemu_chr_parse_compat(label, filename, permit_mux_mon);
718     if (!opts)
719         return NULL;
720 
721     chr = qemu_chr_new_from_opts(opts, context, &err);
722     if (!chr) {
723         error_report_err(err);
724         goto out;
725     }
726 
727     if (qemu_opt_get_bool(opts, "mux", 0)) {
728         assert(permit_mux_mon);
729         monitor_init_hmp(chr, true, &err);
730         if (err) {
731             error_report_err(err);
732             object_unparent(OBJECT(chr));
733             chr = NULL;
734             goto out;
735         }
736     }
737 
738 out:
739     qemu_opts_del(opts);
740     return chr;
741 }
742 
743 static Chardev *qemu_chr_new_permit_mux_mon(const char *label,
744                                           const char *filename,
745                                           bool permit_mux_mon,
746                                           GMainContext *context)
747 {
748     Chardev *chr;
749     chr = qemu_chr_new_noreplay(label, filename, permit_mux_mon, context);
750     if (chr) {
751         if (replay_mode != REPLAY_MODE_NONE) {
752             qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_REPLAY);
753         }
754         if (qemu_chr_replay(chr) && CHARDEV_GET_CLASS(chr)->chr_ioctl) {
755             error_report("Replay: ioctl is not supported "
756                          "for serial devices yet");
757         }
758         replay_register_char_driver(chr);
759     }
760     return chr;
761 }
762 
763 Chardev *qemu_chr_new(const char *label, const char *filename,
764                       GMainContext *context)
765 {
766     return qemu_chr_new_permit_mux_mon(label, filename, false, context);
767 }
768 
769 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename,
770                               GMainContext *context)
771 {
772     return qemu_chr_new_permit_mux_mon(label, filename, true, context);
773 }
774 
775 static int qmp_query_chardev_foreach(Object *obj, void *data)
776 {
777     Chardev *chr = CHARDEV(obj);
778     ChardevInfoList **list = data;
779     ChardevInfo *value = g_malloc0(sizeof(*value));
780 
781     value->label = g_strdup(chr->label);
782     value->filename = g_strdup(chr->filename);
783     value->frontend_open = chr->be && chr->be->fe_open;
784 
785     QAPI_LIST_PREPEND(*list, value);
786 
787     return 0;
788 }
789 
790 ChardevInfoList *qmp_query_chardev(Error **errp)
791 {
792     ChardevInfoList *chr_list = NULL;
793 
794     object_child_foreach(get_chardevs_root(),
795                          qmp_query_chardev_foreach, &chr_list);
796 
797     return chr_list;
798 }
799 
800 static void
801 qmp_prepend_backend(const char *name, void *opaque)
802 {
803     ChardevBackendInfoList **list = opaque;
804     ChardevBackendInfo *value;
805 
806     value = g_new0(ChardevBackendInfo, 1);
807     value->name = g_strdup(name);
808     QAPI_LIST_PREPEND(*list, value);
809 }
810 
811 ChardevBackendInfoList *qmp_query_chardev_backends(Error **errp)
812 {
813     ChardevBackendInfoList *backend_list = NULL;
814 
815     chardev_name_foreach(qmp_prepend_backend, &backend_list);
816 
817     return backend_list;
818 }
819 
820 Chardev *qemu_chr_find(const char *name)
821 {
822     Object *obj = object_resolve_path_component(get_chardevs_root(), name);
823 
824     return obj ? CHARDEV(obj) : NULL;
825 }
826 
827 QemuOptsList qemu_chardev_opts = {
828     .name = "chardev",
829     .implied_opt_name = "backend",
830     .head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
831     .desc = {
832         {
833             .name = "backend",
834             .type = QEMU_OPT_STRING,
835         },{
836             .name = "path",
837             .type = QEMU_OPT_STRING,
838         },{
839             .name = "host",
840             .type = QEMU_OPT_STRING,
841         },{
842             .name = "port",
843             .type = QEMU_OPT_STRING,
844         },{
845             .name = "fd",
846             .type = QEMU_OPT_STRING,
847         },{
848             .name = "localaddr",
849             .type = QEMU_OPT_STRING,
850         },{
851             .name = "localport",
852             .type = QEMU_OPT_STRING,
853         },{
854             .name = "to",
855             .type = QEMU_OPT_NUMBER,
856         },{
857             .name = "ipv4",
858             .type = QEMU_OPT_BOOL,
859         },{
860             .name = "ipv6",
861             .type = QEMU_OPT_BOOL,
862         },{
863             .name = "wait",
864             .type = QEMU_OPT_BOOL,
865         },{
866             .name = "server",
867             .type = QEMU_OPT_BOOL,
868         },{
869             .name = "delay",
870             .type = QEMU_OPT_BOOL,
871         },{
872             .name = "nodelay",
873             .type = QEMU_OPT_BOOL,
874         },{
875             .name = "reconnect",
876             .type = QEMU_OPT_NUMBER,
877         },{
878             .name = "telnet",
879             .type = QEMU_OPT_BOOL,
880         },{
881             .name = "tn3270",
882             .type = QEMU_OPT_BOOL,
883         },{
884             .name = "tls-creds",
885             .type = QEMU_OPT_STRING,
886         },{
887             .name = "tls-authz",
888             .type = QEMU_OPT_STRING,
889         },{
890             .name = "websocket",
891             .type = QEMU_OPT_BOOL,
892         },{
893             .name = "width",
894             .type = QEMU_OPT_NUMBER,
895         },{
896             .name = "height",
897             .type = QEMU_OPT_NUMBER,
898         },{
899             .name = "cols",
900             .type = QEMU_OPT_NUMBER,
901         },{
902             .name = "rows",
903             .type = QEMU_OPT_NUMBER,
904         },{
905             .name = "mux",
906             .type = QEMU_OPT_BOOL,
907         },{
908             .name = "signal",
909             .type = QEMU_OPT_BOOL,
910         },{
911             .name = "name",
912             .type = QEMU_OPT_STRING,
913         },{
914             .name = "debug",
915             .type = QEMU_OPT_NUMBER,
916         },{
917             .name = "size",
918             .type = QEMU_OPT_SIZE,
919         },{
920             .name = "chardev",
921             .type = QEMU_OPT_STRING,
922         },{
923             .name = "append",
924             .type = QEMU_OPT_BOOL,
925         },{
926             .name = "logfile",
927             .type = QEMU_OPT_STRING,
928         },{
929             .name = "logappend",
930             .type = QEMU_OPT_BOOL,
931         },{
932             .name = "mouse",
933             .type = QEMU_OPT_BOOL,
934         },{
935             .name = "clipboard",
936             .type = QEMU_OPT_BOOL,
937 #ifdef CONFIG_LINUX
938         },{
939             .name = "tight",
940             .type = QEMU_OPT_BOOL,
941             .def_value_str = "on",
942         },{
943             .name = "abstract",
944             .type = QEMU_OPT_BOOL,
945 #endif
946         },
947         { /* end of list */ }
948     },
949 };
950 
951 bool qemu_chr_has_feature(Chardev *chr,
952                           ChardevFeature feature)
953 {
954     return test_bit(feature, chr->features);
955 }
956 
957 void qemu_chr_set_feature(Chardev *chr,
958                            ChardevFeature feature)
959 {
960     return set_bit(feature, chr->features);
961 }
962 
963 static Chardev *chardev_new(const char *id, const char *typename,
964                             ChardevBackend *backend,
965                             GMainContext *gcontext,
966                             bool handover_yank_instance,
967                             Error **errp)
968 {
969     Object *obj;
970     Chardev *chr = NULL;
971     Error *local_err = NULL;
972     bool be_opened = true;
973 
974     assert(g_str_has_prefix(typename, "chardev-"));
975     assert(id);
976 
977     obj = object_new(typename);
978     chr = CHARDEV(obj);
979     chr->handover_yank_instance = handover_yank_instance;
980     chr->label = g_strdup(id);
981     chr->gcontext = gcontext;
982 
983     qemu_char_open(chr, backend, &be_opened, &local_err);
984     if (local_err) {
985         error_propagate(errp, local_err);
986         object_unref(obj);
987         return NULL;
988     }
989 
990     if (!chr->filename) {
991         chr->filename = g_strdup(typename + 8);
992     }
993     if (be_opened) {
994         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
995     }
996 
997     return chr;
998 }
999 
1000 Chardev *qemu_chardev_new(const char *id, const char *typename,
1001                           ChardevBackend *backend,
1002                           GMainContext *gcontext,
1003                           Error **errp)
1004 {
1005     Chardev *chr;
1006     g_autofree char *genid = NULL;
1007 
1008     if (!id) {
1009         genid = id_generate(ID_CHR);
1010         id = genid;
1011     }
1012 
1013     chr = chardev_new(id, typename, backend, gcontext, false, errp);
1014     if (!chr) {
1015         return NULL;
1016     }
1017 
1018     if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
1019                                        errp)) {
1020         object_unref(OBJECT(chr));
1021         return NULL;
1022     }
1023     object_unref(OBJECT(chr));
1024 
1025     return chr;
1026 }
1027 
1028 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
1029                                Error **errp)
1030 {
1031     ERRP_GUARD();
1032     const ChardevClass *cc;
1033     ChardevReturn *ret;
1034     g_autoptr(Chardev) chr = NULL;
1035 
1036     if (qemu_chr_find(id)) {
1037         error_setg(errp, "Chardev with id '%s' already exists", id);
1038         return NULL;
1039     }
1040 
1041     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
1042     if (!cc) {
1043         goto err;
1044     }
1045 
1046     chr = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
1047                       backend, NULL, false, errp);
1048     if (!chr) {
1049         goto err;
1050     }
1051 
1052     if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
1053                                        errp)) {
1054         goto err;
1055     }
1056 
1057     ret = g_new0(ChardevReturn, 1);
1058     if (CHARDEV_IS_PTY(chr)) {
1059         ret->pty = g_strdup(chr->filename + 4);
1060         ret->has_pty = true;
1061     }
1062 
1063     return ret;
1064 
1065 err:
1066     error_prepend(errp, "Failed to add chardev '%s': ", id);
1067     return NULL;
1068 }
1069 
1070 ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
1071                                   Error **errp)
1072 {
1073     CharBackend *be;
1074     const ChardevClass *cc, *cc_new;
1075     Chardev *chr, *chr_new;
1076     bool closed_sent = false;
1077     bool handover_yank_instance;
1078     ChardevReturn *ret;
1079 
1080     chr = qemu_chr_find(id);
1081     if (!chr) {
1082         error_setg(errp, "Chardev '%s' does not exist", id);
1083         return NULL;
1084     }
1085 
1086     if (CHARDEV_IS_MUX(chr)) {
1087         error_setg(errp, "Mux device hotswap not supported yet");
1088         return NULL;
1089     }
1090 
1091     if (qemu_chr_replay(chr)) {
1092         error_setg(errp,
1093             "Chardev '%s' cannot be changed in record/replay mode", id);
1094         return NULL;
1095     }
1096 
1097     be = chr->be;
1098     if (!be) {
1099         /* easy case */
1100         object_unparent(OBJECT(chr));
1101         return qmp_chardev_add(id, backend, errp);
1102     }
1103 
1104     if (!be->chr_be_change) {
1105         error_setg(errp, "Chardev user does not support chardev hotswap");
1106         return NULL;
1107     }
1108 
1109     cc = CHARDEV_GET_CLASS(chr);
1110     cc_new = char_get_class(ChardevBackendKind_str(backend->type), errp);
1111     if (!cc_new) {
1112         return NULL;
1113     }
1114 
1115     /*
1116      * The new chardev should not register a yank instance if the current
1117      * chardev has registered one already.
1118      */
1119     handover_yank_instance = cc->supports_yank && cc_new->supports_yank;
1120 
1121     chr_new = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc_new)),
1122                           backend, chr->gcontext, handover_yank_instance, errp);
1123     if (!chr_new) {
1124         return NULL;
1125     }
1126 
1127     if (chr->be_open && !chr_new->be_open) {
1128         qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
1129         closed_sent = true;
1130     }
1131 
1132     chr->be = NULL;
1133     qemu_chr_fe_init(be, chr_new, &error_abort);
1134 
1135     if (be->chr_be_change(be->opaque) < 0) {
1136         error_setg(errp, "Chardev '%s' change failed", chr_new->label);
1137         chr_new->be = NULL;
1138         qemu_chr_fe_init(be, chr, &error_abort);
1139         if (closed_sent) {
1140             qemu_chr_be_event(chr, CHR_EVENT_OPENED);
1141         }
1142         object_unref(OBJECT(chr_new));
1143         return NULL;
1144     }
1145 
1146     /* change successfull, clean up */
1147     chr_new->handover_yank_instance = false;
1148 
1149     /*
1150      * When the old chardev is freed, it should not unregister the yank
1151      * instance if the new chardev needs it.
1152      */
1153     chr->handover_yank_instance = handover_yank_instance;
1154 
1155     object_unparent(OBJECT(chr));
1156     object_property_add_child(get_chardevs_root(), chr_new->label,
1157                               OBJECT(chr_new));
1158     object_unref(OBJECT(chr_new));
1159 
1160     ret = g_new0(ChardevReturn, 1);
1161     if (CHARDEV_IS_PTY(chr_new)) {
1162         ret->pty = g_strdup(chr_new->filename + 4);
1163         ret->has_pty = true;
1164     }
1165 
1166     return ret;
1167 }
1168 
1169 void qmp_chardev_remove(const char *id, Error **errp)
1170 {
1171     Chardev *chr;
1172 
1173     chr = qemu_chr_find(id);
1174     if (chr == NULL) {
1175         error_setg(errp, "Chardev '%s' not found", id);
1176         return;
1177     }
1178     if (qemu_chr_is_busy(chr)) {
1179         error_setg(errp, "Chardev '%s' is busy", id);
1180         return;
1181     }
1182     if (qemu_chr_replay(chr)) {
1183         error_setg(errp,
1184             "Chardev '%s' cannot be unplugged in record/replay mode", id);
1185         return;
1186     }
1187     object_unparent(OBJECT(chr));
1188 }
1189 
1190 void qmp_chardev_send_break(const char *id, Error **errp)
1191 {
1192     Chardev *chr;
1193 
1194     chr = qemu_chr_find(id);
1195     if (chr == NULL) {
1196         error_setg(errp, "Chardev '%s' not found", id);
1197         return;
1198     }
1199     qemu_chr_be_event(chr, CHR_EVENT_BREAK);
1200 }
1201 
1202 /*
1203  * Add a timeout callback for the chardev (in milliseconds), return
1204  * the GSource object created. Please use this to add timeout hook for
1205  * chardev instead of g_timeout_add() and g_timeout_add_seconds(), to
1206  * make sure the gcontext that the task bound to is correct.
1207  */
1208 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
1209                                  GSourceFunc func, void *private)
1210 {
1211     GSource *source = g_timeout_source_new(ms);
1212 
1213     assert(func);
1214     g_source_set_callback(source, func, private, NULL);
1215     g_source_attach(source, chr->gcontext);
1216 
1217     return source;
1218 }
1219 
1220 void qemu_chr_cleanup(void)
1221 {
1222     object_unparent(get_chardevs_root());
1223 }
1224 
1225 static void register_types(void)
1226 {
1227     type_register_static(&char_type_info);
1228 }
1229 
1230 type_init(register_types);
1231