xref: /openbmc/qemu/chardev/char.c (revision bbfff196)
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 "sysemu/sysemu.h"
29 #include "qemu/config-file.h"
30 #include "qemu/error-report.h"
31 #include "qemu/qemu-print.h"
32 #include "chardev/char.h"
33 #include "qapi/error.h"
34 #include "qapi/qapi-commands-char.h"
35 #include "qapi/qmp/qerror.h"
36 #include "sysemu/replay.h"
37 #include "qemu/help_option.h"
38 #include "qemu/option.h"
39 
40 #include "chardev/char-mux.h"
41 
42 /***********************************************************/
43 /* character device */
44 
45 static Object *get_chardevs_root(void)
46 {
47     return container_get(object_get_root(), "/chardevs");
48 }
49 
50 static void chr_be_event(Chardev *s, int event)
51 {
52     CharBackend *be = s->be;
53 
54     if (!be || !be->chr_event) {
55         return;
56     }
57 
58     be->chr_event(be->opaque, event);
59 }
60 
61 void qemu_chr_be_event(Chardev *s, int event)
62 {
63     /* Keep track if the char device is open */
64     switch (event) {
65         case CHR_EVENT_OPENED:
66             s->be_open = 1;
67             break;
68         case CHR_EVENT_CLOSED:
69             s->be_open = 0;
70             break;
71     }
72 
73     CHARDEV_GET_CLASS(s)->chr_be_event(s, event);
74 }
75 
76 /* Not reporting errors from writing to logfile, as logs are
77  * defined to be "best effort" only */
78 static void qemu_chr_write_log(Chardev *s, const uint8_t *buf, size_t len)
79 {
80     size_t done = 0;
81     ssize_t ret;
82 
83     if (s->logfd < 0) {
84         return;
85     }
86 
87     while (done < len) {
88     retry:
89         ret = write(s->logfd, buf + done, len - done);
90         if (ret == -1 && errno == EAGAIN) {
91             g_usleep(100);
92             goto retry;
93         }
94 
95         if (ret <= 0) {
96             return;
97         }
98         done += ret;
99     }
100 }
101 
102 static int qemu_chr_write_buffer(Chardev *s,
103                                  const uint8_t *buf, int len,
104                                  int *offset, bool write_all)
105 {
106     ChardevClass *cc = CHARDEV_GET_CLASS(s);
107     int res = 0;
108     *offset = 0;
109 
110     qemu_mutex_lock(&s->chr_write_lock);
111     while (*offset < len) {
112     retry:
113         res = cc->chr_write(s, buf + *offset, len - *offset);
114         if (res < 0 && errno == EAGAIN && write_all) {
115             g_usleep(100);
116             goto retry;
117         }
118 
119         if (res <= 0) {
120             break;
121         }
122 
123         *offset += res;
124         if (!write_all) {
125             break;
126         }
127     }
128     if (*offset > 0) {
129         qemu_chr_write_log(s, buf, *offset);
130     }
131     qemu_mutex_unlock(&s->chr_write_lock);
132 
133     return res;
134 }
135 
136 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all)
137 {
138     int offset = 0;
139     int res;
140 
141     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_PLAY) {
142         replay_char_write_event_load(&res, &offset);
143         assert(offset <= len);
144         qemu_chr_write_buffer(s, buf, offset, &offset, true);
145         return res;
146     }
147 
148     res = qemu_chr_write_buffer(s, buf, len, &offset, write_all);
149 
150     if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {
151         replay_char_write_event_save(res, offset);
152     }
153 
154     if (res < 0) {
155         return res;
156     }
157     return offset;
158 }
159 
160 int qemu_chr_be_can_write(Chardev *s)
161 {
162     CharBackend *be = s->be;
163 
164     if (!be || !be->chr_can_read) {
165         return 0;
166     }
167 
168     return be->chr_can_read(be->opaque);
169 }
170 
171 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len)
172 {
173     CharBackend *be = s->be;
174 
175     if (be && be->chr_read) {
176         be->chr_read(be->opaque, buf, len);
177     }
178 }
179 
180 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len)
181 {
182     if (qemu_chr_replay(s)) {
183         if (replay_mode == REPLAY_MODE_PLAY) {
184             return;
185         }
186         replay_chr_be_write(s, buf, len);
187     } else {
188         qemu_chr_be_write_impl(s, buf, len);
189     }
190 }
191 
192 void qemu_chr_be_update_read_handlers(Chardev *s,
193                                       GMainContext *context)
194 {
195     ChardevClass *cc = CHARDEV_GET_CLASS(s);
196 
197     assert(qemu_chr_has_feature(s, QEMU_CHAR_FEATURE_GCONTEXT)
198            || !context);
199     s->gcontext = context;
200     if (cc->chr_update_read_handler) {
201         cc->chr_update_read_handler(s);
202     }
203 }
204 
205 int qemu_chr_add_client(Chardev *s, int fd)
206 {
207     return CHARDEV_GET_CLASS(s)->chr_add_client ?
208         CHARDEV_GET_CLASS(s)->chr_add_client(s, fd) : -1;
209 }
210 
211 static void qemu_char_open(Chardev *chr, ChardevBackend *backend,
212                            bool *be_opened, Error **errp)
213 {
214     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
215     /* Any ChardevCommon member would work */
216     ChardevCommon *common = backend ? backend->u.null.data : NULL;
217 
218     if (common && common->has_logfile) {
219         int flags = O_WRONLY | O_CREAT;
220         if (common->has_logappend &&
221             common->logappend) {
222             flags |= O_APPEND;
223         } else {
224             flags |= O_TRUNC;
225         }
226         chr->logfd = qemu_open(common->logfile, flags, 0666);
227         if (chr->logfd < 0) {
228             error_setg_errno(errp, errno,
229                              "Unable to open logfile %s",
230                              common->logfile);
231             return;
232         }
233     }
234 
235     if (cc->open) {
236         cc->open(chr, backend, be_opened, errp);
237     }
238 }
239 
240 static void char_init(Object *obj)
241 {
242     Chardev *chr = CHARDEV(obj);
243 
244     chr->logfd = -1;
245     qemu_mutex_init(&chr->chr_write_lock);
246 
247     /*
248      * Assume if chr_update_read_handler is implemented it will
249      * take the updated gcontext into account.
250      */
251     if (CHARDEV_GET_CLASS(chr)->chr_update_read_handler) {
252         qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_GCONTEXT);
253     }
254 
255 }
256 
257 static int null_chr_write(Chardev *chr, const uint8_t *buf, int len)
258 {
259     return len;
260 }
261 
262 static void char_class_init(ObjectClass *oc, void *data)
263 {
264     ChardevClass *cc = CHARDEV_CLASS(oc);
265 
266     cc->chr_write = null_chr_write;
267     cc->chr_be_event = chr_be_event;
268 }
269 
270 static void char_finalize(Object *obj)
271 {
272     Chardev *chr = CHARDEV(obj);
273 
274     if (chr->be) {
275         chr->be->chr = NULL;
276     }
277     g_free(chr->filename);
278     g_free(chr->label);
279     if (chr->logfd != -1) {
280         close(chr->logfd);
281     }
282     qemu_mutex_destroy(&chr->chr_write_lock);
283 }
284 
285 static const TypeInfo char_type_info = {
286     .name = TYPE_CHARDEV,
287     .parent = TYPE_OBJECT,
288     .instance_size = sizeof(Chardev),
289     .instance_init = char_init,
290     .instance_finalize = char_finalize,
291     .abstract = true,
292     .class_size = sizeof(ChardevClass),
293     .class_init = char_class_init,
294 };
295 
296 static int chardev_machine_done_notify_one(Object *child, void *opaque)
297 {
298     Chardev *chr = (Chardev *)child;
299     ChardevClass *class = CHARDEV_GET_CLASS(chr);
300 
301     if (class->chr_machine_done) {
302         return class->chr_machine_done(chr);
303     }
304 
305     return 0;
306 }
307 
308 static void chardev_machine_done_hook(Notifier *notifier, void *unused)
309 {
310     int ret = object_child_foreach(get_chardevs_root(),
311                                    chardev_machine_done_notify_one, NULL);
312 
313     if (ret) {
314         error_report("Failed to call chardev machine_done hooks");
315         exit(1);
316     }
317 }
318 
319 static Notifier chardev_machine_done_notify = {
320     .notify = chardev_machine_done_hook,
321 };
322 
323 static bool qemu_chr_is_busy(Chardev *s)
324 {
325     if (CHARDEV_IS_MUX(s)) {
326         MuxChardev *d = MUX_CHARDEV(s);
327         return d->mux_cnt >= 0;
328     } else {
329         return s->be != NULL;
330     }
331 }
332 
333 int qemu_chr_wait_connected(Chardev *chr, Error **errp)
334 {
335     ChardevClass *cc = CHARDEV_GET_CLASS(chr);
336 
337     if (cc->chr_wait_connected) {
338         return cc->chr_wait_connected(chr, errp);
339     }
340 
341     return 0;
342 }
343 
344 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename,
345                                 bool permit_mux_mon)
346 {
347     char host[65], port[33], width[8], height[8];
348     int pos;
349     const char *p;
350     QemuOpts *opts;
351     Error *local_err = NULL;
352 
353     opts = qemu_opts_create(qemu_find_opts("chardev"), label, 1, &local_err);
354     if (local_err) {
355         error_report_err(local_err);
356         return NULL;
357     }
358 
359     if (strstart(filename, "mon:", &p)) {
360         if (!permit_mux_mon) {
361             error_report("mon: isn't supported in this context");
362             return NULL;
363         }
364         filename = p;
365         qemu_opt_set(opts, "mux", "on", &error_abort);
366         if (strcmp(filename, "stdio") == 0) {
367             /* Monitor is muxed to stdio: do not exit on Ctrl+C by default
368              * but pass it to the guest.  Handle this only for compat syntax,
369              * for -chardev syntax we have special option for this.
370              * This is what -nographic did, redirecting+muxing serial+monitor
371              * to stdio causing Ctrl+C to be passed to guest. */
372             qemu_opt_set(opts, "signal", "off", &error_abort);
373         }
374     }
375 
376     if (strcmp(filename, "null")    == 0 ||
377         strcmp(filename, "pty")     == 0 ||
378         strcmp(filename, "msmouse") == 0 ||
379         strcmp(filename, "wctablet") == 0 ||
380         strcmp(filename, "braille") == 0 ||
381         strcmp(filename, "testdev") == 0 ||
382         strcmp(filename, "stdio")   == 0) {
383         qemu_opt_set(opts, "backend", filename, &error_abort);
384         return opts;
385     }
386     if (strstart(filename, "vc", &p)) {
387         qemu_opt_set(opts, "backend", "vc", &error_abort);
388         if (*p == ':') {
389             if (sscanf(p+1, "%7[0-9]x%7[0-9]", width, height) == 2) {
390                 /* pixels */
391                 qemu_opt_set(opts, "width", width, &error_abort);
392                 qemu_opt_set(opts, "height", height, &error_abort);
393             } else if (sscanf(p+1, "%7[0-9]Cx%7[0-9]C", width, height) == 2) {
394                 /* chars */
395                 qemu_opt_set(opts, "cols", width, &error_abort);
396                 qemu_opt_set(opts, "rows", height, &error_abort);
397             } else {
398                 goto fail;
399             }
400         }
401         return opts;
402     }
403     if (strcmp(filename, "con:") == 0) {
404         qemu_opt_set(opts, "backend", "console", &error_abort);
405         return opts;
406     }
407     if (strstart(filename, "COM", NULL)) {
408         qemu_opt_set(opts, "backend", "serial", &error_abort);
409         qemu_opt_set(opts, "path", filename, &error_abort);
410         return opts;
411     }
412     if (strstart(filename, "file:", &p)) {
413         qemu_opt_set(opts, "backend", "file", &error_abort);
414         qemu_opt_set(opts, "path", p, &error_abort);
415         return opts;
416     }
417     if (strstart(filename, "pipe:", &p)) {
418         qemu_opt_set(opts, "backend", "pipe", &error_abort);
419         qemu_opt_set(opts, "path", p, &error_abort);
420         return opts;
421     }
422     if (strstart(filename, "tcp:", &p) ||
423         strstart(filename, "telnet:", &p) ||
424         strstart(filename, "tn3270:", &p) ||
425         strstart(filename, "websocket:", &p)) {
426         if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
427             host[0] = 0;
428             if (sscanf(p, ":%32[^,]%n", port, &pos) < 1)
429                 goto fail;
430         }
431         qemu_opt_set(opts, "backend", "socket", &error_abort);
432         qemu_opt_set(opts, "host", host, &error_abort);
433         qemu_opt_set(opts, "port", port, &error_abort);
434         if (p[pos] == ',') {
435             qemu_opts_do_parse(opts, p+pos+1, NULL, &local_err);
436             if (local_err) {
437                 error_report_err(local_err);
438                 goto fail;
439             }
440         }
441         if (strstart(filename, "telnet:", &p)) {
442             qemu_opt_set(opts, "telnet", "on", &error_abort);
443         } else if (strstart(filename, "tn3270:", &p)) {
444             qemu_opt_set(opts, "tn3270", "on", &error_abort);
445         } else if (strstart(filename, "websocket:", &p)) {
446             qemu_opt_set(opts, "websocket", "on", &error_abort);
447         }
448         return opts;
449     }
450     if (strstart(filename, "udp:", &p)) {
451         qemu_opt_set(opts, "backend", "udp", &error_abort);
452         if (sscanf(p, "%64[^:]:%32[^@,]%n", host, port, &pos) < 2) {
453             host[0] = 0;
454             if (sscanf(p, ":%32[^@,]%n", port, &pos) < 1) {
455                 goto fail;
456             }
457         }
458         qemu_opt_set(opts, "host", host, &error_abort);
459         qemu_opt_set(opts, "port", port, &error_abort);
460         if (p[pos] == '@') {
461             p += pos + 1;
462             if (sscanf(p, "%64[^:]:%32[^,]%n", host, port, &pos) < 2) {
463                 host[0] = 0;
464                 if (sscanf(p, ":%32[^,]%n", port, &pos) < 1) {
465                     goto fail;
466                 }
467             }
468             qemu_opt_set(opts, "localaddr", host, &error_abort);
469             qemu_opt_set(opts, "localport", port, &error_abort);
470         }
471         return opts;
472     }
473     if (strstart(filename, "unix:", &p)) {
474         qemu_opt_set(opts, "backend", "socket", &error_abort);
475         qemu_opts_do_parse(opts, p, "path", &local_err);
476         if (local_err) {
477             error_report_err(local_err);
478             goto fail;
479         }
480         return opts;
481     }
482     if (strstart(filename, "/dev/parport", NULL) ||
483         strstart(filename, "/dev/ppi", NULL)) {
484         qemu_opt_set(opts, "backend", "parallel", &error_abort);
485         qemu_opt_set(opts, "path", filename, &error_abort);
486         return opts;
487     }
488     if (strstart(filename, "/dev/", NULL)) {
489         qemu_opt_set(opts, "backend", "serial", &error_abort);
490         qemu_opt_set(opts, "path", filename, &error_abort);
491         return opts;
492     }
493 
494     error_report("'%s' is not a valid char driver", filename);
495 
496 fail:
497     qemu_opts_del(opts);
498     return NULL;
499 }
500 
501 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend)
502 {
503     const char *logfile = qemu_opt_get(opts, "logfile");
504 
505     backend->has_logfile = logfile != NULL;
506     backend->logfile = g_strdup(logfile);
507 
508     backend->has_logappend = true;
509     backend->logappend = qemu_opt_get_bool(opts, "logappend", false);
510 }
511 
512 static const ChardevClass *char_get_class(const char *driver, Error **errp)
513 {
514     ObjectClass *oc;
515     const ChardevClass *cc;
516     char *typename = g_strdup_printf("chardev-%s", driver);
517 
518     oc = object_class_by_name(typename);
519     g_free(typename);
520 
521     if (!object_class_dynamic_cast(oc, TYPE_CHARDEV)) {
522         error_setg(errp, "'%s' is not a valid char driver name", driver);
523         return NULL;
524     }
525 
526     if (object_class_is_abstract(oc)) {
527         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "driver",
528                    "abstract device type");
529         return NULL;
530     }
531 
532     cc = CHARDEV_CLASS(oc);
533     if (cc->internal) {
534         error_setg(errp, "'%s' is not a valid char driver name", driver);
535         return NULL;
536     }
537 
538     return cc;
539 }
540 
541 static const struct ChardevAlias {
542     const char *typename;
543     const char *alias;
544 } chardev_alias_table[] = {
545 #ifdef HAVE_CHARDEV_PARPORT
546     { "parallel", "parport" },
547 #endif
548 #ifdef HAVE_CHARDEV_SERIAL
549     { "serial", "tty" },
550 #endif
551 };
552 
553 typedef struct ChadevClassFE {
554     void (*fn)(const char *name, void *opaque);
555     void *opaque;
556 } ChadevClassFE;
557 
558 static void
559 chardev_class_foreach(ObjectClass *klass, void *opaque)
560 {
561     ChadevClassFE *fe = opaque;
562 
563     assert(g_str_has_prefix(object_class_get_name(klass), "chardev-"));
564     if (CHARDEV_CLASS(klass)->internal) {
565         return;
566     }
567 
568     fe->fn(object_class_get_name(klass) + 8, fe->opaque);
569 }
570 
571 static void
572 chardev_name_foreach(void (*fn)(const char *name, void *opaque), void *opaque)
573 {
574     ChadevClassFE fe = { .fn = fn, .opaque = opaque };
575     int i;
576 
577     object_class_foreach(chardev_class_foreach, TYPE_CHARDEV, false, &fe);
578 
579     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
580         fn(chardev_alias_table[i].alias, opaque);
581     }
582 }
583 
584 static void
585 help_string_append(const char *name, void *opaque)
586 {
587     GString *str = opaque;
588 
589     g_string_append_printf(str, "\n  %s", name);
590 }
591 
592 static const char *chardev_alias_translate(const char *name)
593 {
594     int i;
595     for (i = 0; i < (int)ARRAY_SIZE(chardev_alias_table); i++) {
596         if (g_strcmp0(chardev_alias_table[i].alias, name) == 0) {
597             return chardev_alias_table[i].typename;
598         }
599     }
600     return name;
601 }
602 
603 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts, Error **errp)
604 {
605     Error *local_err = NULL;
606     const ChardevClass *cc;
607     ChardevBackend *backend = NULL;
608     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
609 
610     if (name == NULL) {
611         error_setg(errp, "chardev: \"%s\" missing backend",
612                    qemu_opts_id(opts));
613         return NULL;
614     }
615 
616     cc = char_get_class(name, errp);
617     if (cc == NULL) {
618         return NULL;
619     }
620 
621     backend = g_new0(ChardevBackend, 1);
622     backend->type = CHARDEV_BACKEND_KIND_NULL;
623 
624     if (cc->parse) {
625         cc->parse(opts, backend, &local_err);
626         if (local_err) {
627             error_propagate(errp, local_err);
628             qapi_free_ChardevBackend(backend);
629             return NULL;
630         }
631     } else {
632         ChardevCommon *ccom = g_new0(ChardevCommon, 1);
633         qemu_chr_parse_common(opts, ccom);
634         backend->u.null.data = ccom; /* Any ChardevCommon member would work */
635     }
636 
637     return backend;
638 }
639 
640 Chardev *qemu_chr_new_from_opts(QemuOpts *opts, GMainContext *context,
641                                 Error **errp)
642 {
643     const ChardevClass *cc;
644     Chardev *chr = NULL;
645     ChardevBackend *backend = NULL;
646     const char *name = chardev_alias_translate(qemu_opt_get(opts, "backend"));
647     const char *id = qemu_opts_id(opts);
648     char *bid = NULL;
649 
650     if (name && is_help_option(name)) {
651         GString *str = g_string_new("");
652 
653         chardev_name_foreach(help_string_append, str);
654 
655         qemu_printf("Available chardev backend types: %s\n", str->str);
656         g_string_free(str, true);
657         return NULL;
658     }
659 
660     if (id == NULL) {
661         error_setg(errp, "chardev: no id specified");
662         return NULL;
663     }
664 
665     backend = qemu_chr_parse_opts(opts, errp);
666     if (backend == NULL) {
667         return NULL;
668     }
669 
670     cc = char_get_class(name, errp);
671     if (cc == NULL) {
672         goto out;
673     }
674 
675     if (qemu_opt_get_bool(opts, "mux", 0)) {
676         bid = g_strdup_printf("%s-base", id);
677     }
678 
679     chr = qemu_chardev_new(bid ? bid : id,
680                            object_class_get_name(OBJECT_CLASS(cc)),
681                            backend, context, errp);
682 
683     if (chr == NULL) {
684         goto out;
685     }
686 
687     if (bid) {
688         Chardev *mux;
689         qapi_free_ChardevBackend(backend);
690         backend = g_new0(ChardevBackend, 1);
691         backend->type = CHARDEV_BACKEND_KIND_MUX;
692         backend->u.mux.data = g_new0(ChardevMux, 1);
693         backend->u.mux.data->chardev = g_strdup(bid);
694         mux = qemu_chardev_new(id, TYPE_CHARDEV_MUX, backend, context, errp);
695         if (mux == NULL) {
696             object_unparent(OBJECT(chr));
697             chr = NULL;
698             goto out;
699         }
700         chr = mux;
701     }
702 
703 out:
704     qapi_free_ChardevBackend(backend);
705     g_free(bid);
706     return chr;
707 }
708 
709 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
710                                bool permit_mux_mon, GMainContext *context)
711 {
712     const char *p;
713     Chardev *chr;
714     QemuOpts *opts;
715     Error *err = NULL;
716 
717     if (strstart(filename, "chardev:", &p)) {
718         return qemu_chr_find(p);
719     }
720 
721     opts = qemu_chr_parse_compat(label, filename, permit_mux_mon);
722     if (!opts)
723         return NULL;
724 
725     chr = qemu_chr_new_from_opts(opts, context, &err);
726     if (!chr) {
727         error_report_err(err);
728         goto out;
729     }
730 
731     if (qemu_opt_get_bool(opts, "mux", 0)) {
732         assert(permit_mux_mon);
733         monitor_init(chr, MONITOR_USE_READLINE);
734     }
735 
736 out:
737     qemu_opts_del(opts);
738     return chr;
739 }
740 
741 static Chardev *qemu_chr_new_permit_mux_mon(const char *label,
742                                           const char *filename,
743                                           bool permit_mux_mon,
744                                           GMainContext *context)
745 {
746     Chardev *chr;
747     chr = qemu_chr_new_noreplay(label, filename, permit_mux_mon, context);
748     if (chr) {
749         if (replay_mode != REPLAY_MODE_NONE) {
750             qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_REPLAY);
751         }
752         if (qemu_chr_replay(chr) && CHARDEV_GET_CLASS(chr)->chr_ioctl) {
753             error_report("Replay: ioctl is not supported "
754                          "for serial devices yet");
755         }
756         replay_register_char_driver(chr);
757     }
758     return chr;
759 }
760 
761 Chardev *qemu_chr_new(const char *label, const char *filename,
762                       GMainContext *context)
763 {
764     return qemu_chr_new_permit_mux_mon(label, filename, false, context);
765 }
766 
767 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename,
768                               GMainContext *context)
769 {
770     return qemu_chr_new_permit_mux_mon(label, filename, true, context);
771 }
772 
773 static int qmp_query_chardev_foreach(Object *obj, void *data)
774 {
775     Chardev *chr = CHARDEV(obj);
776     ChardevInfoList **list = data;
777     ChardevInfoList *info = g_malloc0(sizeof(*info));
778 
779     info->value = g_malloc0(sizeof(*info->value));
780     info->value->label = g_strdup(chr->label);
781     info->value->filename = g_strdup(chr->filename);
782     info->value->frontend_open = chr->be && chr->be->fe_open;
783 
784     info->next = *list;
785     *list = info;
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     ChardevBackendInfoList *info = g_malloc0(sizeof(*info));
805 
806     info->value = g_malloc0(sizeof(*info->value));
807     info->value->name = g_strdup(name);
808     info->next = *list;
809     *list = info;
810 }
811 
812 ChardevBackendInfoList *qmp_query_chardev_backends(Error **errp)
813 {
814     ChardevBackendInfoList *backend_list = NULL;
815 
816     chardev_name_foreach(qmp_prepend_backend, &backend_list);
817 
818     return backend_list;
819 }
820 
821 Chardev *qemu_chr_find(const char *name)
822 {
823     Object *obj = object_resolve_path_component(get_chardevs_root(), name);
824 
825     return obj ? CHARDEV(obj) : NULL;
826 }
827 
828 QemuOptsList qemu_chardev_opts = {
829     .name = "chardev",
830     .implied_opt_name = "backend",
831     .head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
832     .desc = {
833         {
834             .name = "backend",
835             .type = QEMU_OPT_STRING,
836         },{
837             .name = "path",
838             .type = QEMU_OPT_STRING,
839         },{
840             .name = "host",
841             .type = QEMU_OPT_STRING,
842         },{
843             .name = "port",
844             .type = QEMU_OPT_STRING,
845         },{
846             .name = "fd",
847             .type = QEMU_OPT_STRING,
848         },{
849             .name = "localaddr",
850             .type = QEMU_OPT_STRING,
851         },{
852             .name = "localport",
853             .type = QEMU_OPT_STRING,
854         },{
855             .name = "to",
856             .type = QEMU_OPT_NUMBER,
857         },{
858             .name = "ipv4",
859             .type = QEMU_OPT_BOOL,
860         },{
861             .name = "ipv6",
862             .type = QEMU_OPT_BOOL,
863         },{
864             .name = "wait",
865             .type = QEMU_OPT_BOOL,
866         },{
867             .name = "server",
868             .type = QEMU_OPT_BOOL,
869         },{
870             .name = "delay",
871             .type = QEMU_OPT_BOOL,
872         },{
873             .name = "reconnect",
874             .type = QEMU_OPT_NUMBER,
875         },{
876             .name = "telnet",
877             .type = QEMU_OPT_BOOL,
878         },{
879             .name = "tn3270",
880             .type = QEMU_OPT_BOOL,
881         },{
882             .name = "tls-creds",
883             .type = QEMU_OPT_STRING,
884         },{
885             .name = "tls-authz",
886             .type = QEMU_OPT_STRING,
887         },{
888             .name = "websocket",
889             .type = QEMU_OPT_BOOL,
890         },{
891             .name = "width",
892             .type = QEMU_OPT_NUMBER,
893         },{
894             .name = "height",
895             .type = QEMU_OPT_NUMBER,
896         },{
897             .name = "cols",
898             .type = QEMU_OPT_NUMBER,
899         },{
900             .name = "rows",
901             .type = QEMU_OPT_NUMBER,
902         },{
903             .name = "mux",
904             .type = QEMU_OPT_BOOL,
905         },{
906             .name = "signal",
907             .type = QEMU_OPT_BOOL,
908         },{
909             .name = "name",
910             .type = QEMU_OPT_STRING,
911         },{
912             .name = "debug",
913             .type = QEMU_OPT_NUMBER,
914         },{
915             .name = "size",
916             .type = QEMU_OPT_SIZE,
917         },{
918             .name = "chardev",
919             .type = QEMU_OPT_STRING,
920         },{
921             .name = "append",
922             .type = QEMU_OPT_BOOL,
923         },{
924             .name = "logfile",
925             .type = QEMU_OPT_STRING,
926         },{
927             .name = "logappend",
928             .type = QEMU_OPT_BOOL,
929         },
930         { /* end of list */ }
931     },
932 };
933 
934 bool qemu_chr_has_feature(Chardev *chr,
935                           ChardevFeature feature)
936 {
937     return test_bit(feature, chr->features);
938 }
939 
940 void qemu_chr_set_feature(Chardev *chr,
941                            ChardevFeature feature)
942 {
943     return set_bit(feature, chr->features);
944 }
945 
946 Chardev *qemu_chardev_new(const char *id, const char *typename,
947                           ChardevBackend *backend,
948                           GMainContext *gcontext,
949                           Error **errp)
950 {
951     Object *obj;
952     Chardev *chr = NULL;
953     Error *local_err = NULL;
954     bool be_opened = true;
955 
956     assert(g_str_has_prefix(typename, "chardev-"));
957 
958     obj = object_new(typename);
959     chr = CHARDEV(obj);
960     chr->label = g_strdup(id);
961     chr->gcontext = gcontext;
962 
963     qemu_char_open(chr, backend, &be_opened, &local_err);
964     if (local_err) {
965         goto end;
966     }
967 
968     if (!chr->filename) {
969         chr->filename = g_strdup(typename + 8);
970     }
971     if (be_opened) {
972         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
973     }
974 
975     if (id) {
976         object_property_add_child(get_chardevs_root(), id, obj, &local_err);
977         if (local_err) {
978             goto end;
979         }
980         object_unref(obj);
981     }
982 
983 end:
984     if (local_err) {
985         error_propagate(errp, local_err);
986         object_unref(obj);
987         return NULL;
988     }
989 
990     return chr;
991 }
992 
993 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
994                                Error **errp)
995 {
996     const ChardevClass *cc;
997     ChardevReturn *ret;
998     Chardev *chr;
999 
1000     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
1001     if (!cc) {
1002         return NULL;
1003     }
1004 
1005     chr = qemu_chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
1006                            backend, NULL, errp);
1007     if (!chr) {
1008         return NULL;
1009     }
1010 
1011     ret = g_new0(ChardevReturn, 1);
1012     if (CHARDEV_IS_PTY(chr)) {
1013         ret->pty = g_strdup(chr->filename + 4);
1014         ret->has_pty = true;
1015     }
1016 
1017     return ret;
1018 }
1019 
1020 ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
1021                                   Error **errp)
1022 {
1023     CharBackend *be;
1024     const ChardevClass *cc;
1025     Chardev *chr, *chr_new;
1026     bool closed_sent = false;
1027     ChardevReturn *ret;
1028 
1029     chr = qemu_chr_find(id);
1030     if (!chr) {
1031         error_setg(errp, "Chardev '%s' does not exist", id);
1032         return NULL;
1033     }
1034 
1035     if (CHARDEV_IS_MUX(chr)) {
1036         error_setg(errp, "Mux device hotswap not supported yet");
1037         return NULL;
1038     }
1039 
1040     if (qemu_chr_replay(chr)) {
1041         error_setg(errp,
1042             "Chardev '%s' cannot be changed in record/replay mode", id);
1043         return NULL;
1044     }
1045 
1046     be = chr->be;
1047     if (!be) {
1048         /* easy case */
1049         object_unparent(OBJECT(chr));
1050         return qmp_chardev_add(id, backend, errp);
1051     }
1052 
1053     if (!be->chr_be_change) {
1054         error_setg(errp, "Chardev user does not support chardev hotswap");
1055         return NULL;
1056     }
1057 
1058     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
1059     if (!cc) {
1060         return NULL;
1061     }
1062 
1063     chr_new = qemu_chardev_new(NULL, object_class_get_name(OBJECT_CLASS(cc)),
1064                                backend, chr->gcontext, errp);
1065     if (!chr_new) {
1066         return NULL;
1067     }
1068     chr_new->label = g_strdup(id);
1069 
1070     if (chr->be_open && !chr_new->be_open) {
1071         qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
1072         closed_sent = true;
1073     }
1074 
1075     chr->be = NULL;
1076     qemu_chr_fe_init(be, chr_new, &error_abort);
1077 
1078     if (be->chr_be_change(be->opaque) < 0) {
1079         error_setg(errp, "Chardev '%s' change failed", chr_new->label);
1080         chr_new->be = NULL;
1081         qemu_chr_fe_init(be, chr, &error_abort);
1082         if (closed_sent) {
1083             qemu_chr_be_event(chr, CHR_EVENT_OPENED);
1084         }
1085         object_unref(OBJECT(chr_new));
1086         return NULL;
1087     }
1088 
1089     object_unparent(OBJECT(chr));
1090     object_property_add_child(get_chardevs_root(), chr_new->label,
1091                               OBJECT(chr_new), &error_abort);
1092     object_unref(OBJECT(chr_new));
1093 
1094     ret = g_new0(ChardevReturn, 1);
1095     if (CHARDEV_IS_PTY(chr_new)) {
1096         ret->pty = g_strdup(chr_new->filename + 4);
1097         ret->has_pty = true;
1098     }
1099 
1100     return ret;
1101 }
1102 
1103 void qmp_chardev_remove(const char *id, Error **errp)
1104 {
1105     Chardev *chr;
1106 
1107     chr = qemu_chr_find(id);
1108     if (chr == NULL) {
1109         error_setg(errp, "Chardev '%s' not found", id);
1110         return;
1111     }
1112     if (qemu_chr_is_busy(chr)) {
1113         error_setg(errp, "Chardev '%s' is busy", id);
1114         return;
1115     }
1116     if (qemu_chr_replay(chr)) {
1117         error_setg(errp,
1118             "Chardev '%s' cannot be unplugged in record/replay mode", id);
1119         return;
1120     }
1121     object_unparent(OBJECT(chr));
1122 }
1123 
1124 void qmp_chardev_send_break(const char *id, Error **errp)
1125 {
1126     Chardev *chr;
1127 
1128     chr = qemu_chr_find(id);
1129     if (chr == NULL) {
1130         error_setg(errp, "Chardev '%s' not found", id);
1131         return;
1132     }
1133     qemu_chr_be_event(chr, CHR_EVENT_BREAK);
1134 }
1135 
1136 /*
1137  * Add a timeout callback for the chardev (in milliseconds), return
1138  * the GSource object created. Please use this to add timeout hook for
1139  * chardev instead of g_timeout_add() and g_timeout_add_seconds(), to
1140  * make sure the gcontext that the task bound to is correct.
1141  */
1142 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
1143                                  GSourceFunc func, void *private)
1144 {
1145     GSource *source = g_timeout_source_new(ms);
1146 
1147     assert(func);
1148     g_source_set_callback(source, func, private, NULL);
1149     g_source_attach(source, chr->gcontext);
1150 
1151     return source;
1152 }
1153 
1154 void qemu_chr_cleanup(void)
1155 {
1156     object_unparent(get_chardevs_root());
1157 }
1158 
1159 static void register_types(void)
1160 {
1161     type_register_static(&char_type_info);
1162 
1163     /* this must be done after machine init, since we register FEs with muxes
1164      * as part of realize functions like serial_isa_realizefn when -nographic
1165      * is specified
1166      */
1167     qemu_add_machine_init_done_notifier(&chardev_machine_done_notify);
1168 }
1169 
1170 type_init(register_types);
1171