xref: /openbmc/qemu/chardev/char.c (revision ffe98631)
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, const 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, const 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->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->logfile = g_strdup(logfile);
500     backend->has_logappend = true;
501     backend->logappend = qemu_opt_get_bool(opts, "logappend", false);
502 }
503 
504 static const ChardevClass *char_get_class(const char *driver, Error **errp)
505 {
506     ObjectClass *oc;
507     const ChardevClass *cc;
508     char *typename = g_strdup_printf("chardev-%s", driver);
509 
510     oc = module_object_class_by_name(typename);
511     g_free(typename);
512 
513     if (!object_class_dynamic_cast(oc, TYPE_CHARDEV)) {
514         error_setg(errp, "'%s' is not a valid char driver name", driver);
515         return NULL;
516     }
517 
518     if (object_class_is_abstract(oc)) {
519         error_setg(errp, QERR_INVALID_PARAMETER_VALUE, "driver",
520                    "an abstract device type");
521         return NULL;
522     }
523 
524     cc = CHARDEV_CLASS(oc);
525     if (cc->internal) {
526         error_setg(errp, "'%s' is not a valid char driver name", driver);
527         return NULL;
528     }
529 
530     return cc;
531 }
532 
533 typedef struct ChadevClassFE {
534     void (*fn)(const char *name, void *opaque);
535     void *opaque;
536 } ChadevClassFE;
537 
538 static void
539 chardev_class_foreach(ObjectClass *klass, void *opaque)
540 {
541     ChadevClassFE *fe = opaque;
542 
543     assert(g_str_has_prefix(object_class_get_name(klass), "chardev-"));
544     if (CHARDEV_CLASS(klass)->internal) {
545         return;
546     }
547 
548     fe->fn(object_class_get_name(klass) + 8, fe->opaque);
549 }
550 
551 static void
552 chardev_name_foreach(void (*fn)(const char *name, void *opaque),
553                      void *opaque)
554 {
555     ChadevClassFE fe = { .fn = fn, .opaque = opaque };
556 
557     object_class_foreach(chardev_class_foreach, TYPE_CHARDEV, false, &fe);
558 }
559 
560 static void
561 help_string_append(const char *name, void *opaque)
562 {
563     GString *str = opaque;
564 
565     g_string_append_printf(str, "\n  %s", name);
566 }
567 
568 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts, Error **errp)
569 {
570     Error *local_err = NULL;
571     const ChardevClass *cc;
572     ChardevBackend *backend = NULL;
573     const char *name = qemu_opt_get(opts, "backend");
574 
575     if (name == NULL) {
576         error_setg(errp, "chardev: \"%s\" missing backend",
577                    qemu_opts_id(opts));
578         return NULL;
579     }
580 
581     cc = char_get_class(name, errp);
582     if (cc == NULL) {
583         return NULL;
584     }
585 
586     backend = g_new0(ChardevBackend, 1);
587     backend->type = CHARDEV_BACKEND_KIND_NULL;
588 
589     if (cc->parse) {
590         cc->parse(opts, backend, &local_err);
591         if (local_err) {
592             error_propagate(errp, local_err);
593             qapi_free_ChardevBackend(backend);
594             return NULL;
595         }
596     } else {
597         ChardevCommon *ccom = g_new0(ChardevCommon, 1);
598         qemu_chr_parse_common(opts, ccom);
599         backend->u.null.data = ccom; /* Any ChardevCommon member would work */
600     }
601 
602     return backend;
603 }
604 
605 Chardev *qemu_chr_new_from_opts(QemuOpts *opts, GMainContext *context,
606                                 Error **errp)
607 {
608     const ChardevClass *cc;
609     Chardev *chr = NULL;
610     ChardevBackend *backend = NULL;
611     const char *name = qemu_opt_get(opts, "backend");
612     const char *id = qemu_opts_id(opts);
613     char *bid = NULL;
614 
615     if (name && is_help_option(name)) {
616         GString *str = g_string_new("");
617 
618         chardev_name_foreach(help_string_append, str);
619 
620         qemu_printf("Available chardev backend types: %s\n", str->str);
621         g_string_free(str, true);
622         return NULL;
623     }
624 
625     if (id == NULL) {
626         error_setg(errp, "chardev: no id specified");
627         return NULL;
628     }
629 
630     backend = qemu_chr_parse_opts(opts, errp);
631     if (backend == NULL) {
632         return NULL;
633     }
634 
635     cc = char_get_class(name, errp);
636     if (cc == NULL) {
637         goto out;
638     }
639 
640     if (qemu_opt_get_bool(opts, "mux", 0)) {
641         bid = g_strdup_printf("%s-base", id);
642     }
643 
644     chr = qemu_chardev_new(bid ? bid : id,
645                            object_class_get_name(OBJECT_CLASS(cc)),
646                            backend, context, errp);
647 
648     if (chr == NULL) {
649         goto out;
650     }
651 
652     if (bid) {
653         Chardev *mux;
654         qapi_free_ChardevBackend(backend);
655         backend = g_new0(ChardevBackend, 1);
656         backend->type = CHARDEV_BACKEND_KIND_MUX;
657         backend->u.mux.data = g_new0(ChardevMux, 1);
658         backend->u.mux.data->chardev = g_strdup(bid);
659         mux = qemu_chardev_new(id, TYPE_CHARDEV_MUX, backend, context, errp);
660         if (mux == NULL) {
661             object_unparent(OBJECT(chr));
662             chr = NULL;
663             goto out;
664         }
665         chr = mux;
666     }
667 
668 out:
669     qapi_free_ChardevBackend(backend);
670     g_free(bid);
671     return chr;
672 }
673 
674 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
675                                bool permit_mux_mon, GMainContext *context)
676 {
677     const char *p;
678     Chardev *chr;
679     QemuOpts *opts;
680     Error *err = NULL;
681 
682     if (strstart(filename, "chardev:", &p)) {
683         return qemu_chr_find(p);
684     }
685 
686     opts = qemu_chr_parse_compat(label, filename, permit_mux_mon);
687     if (!opts)
688         return NULL;
689 
690     chr = qemu_chr_new_from_opts(opts, context, &err);
691     if (!chr) {
692         error_report_err(err);
693         goto out;
694     }
695 
696     if (qemu_opt_get_bool(opts, "mux", 0)) {
697         assert(permit_mux_mon);
698         monitor_init_hmp(chr, true, &err);
699         if (err) {
700             error_report_err(err);
701             object_unparent(OBJECT(chr));
702             chr = NULL;
703             goto out;
704         }
705     }
706 
707 out:
708     qemu_opts_del(opts);
709     return chr;
710 }
711 
712 static Chardev *qemu_chr_new_permit_mux_mon(const char *label,
713                                           const char *filename,
714                                           bool permit_mux_mon,
715                                           GMainContext *context)
716 {
717     Chardev *chr;
718     chr = qemu_chr_new_noreplay(label, filename, permit_mux_mon, context);
719     if (chr) {
720         if (replay_mode != REPLAY_MODE_NONE) {
721             qemu_chr_set_feature(chr, QEMU_CHAR_FEATURE_REPLAY);
722         }
723         if (qemu_chr_replay(chr) && CHARDEV_GET_CLASS(chr)->chr_ioctl) {
724             error_report("Replay: ioctl is not supported "
725                          "for serial devices yet");
726         }
727         replay_register_char_driver(chr);
728     }
729     return chr;
730 }
731 
732 Chardev *qemu_chr_new(const char *label, const char *filename,
733                       GMainContext *context)
734 {
735     return qemu_chr_new_permit_mux_mon(label, filename, false, context);
736 }
737 
738 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename,
739                               GMainContext *context)
740 {
741     return qemu_chr_new_permit_mux_mon(label, filename, true, context);
742 }
743 
744 static int qmp_query_chardev_foreach(Object *obj, void *data)
745 {
746     Chardev *chr = CHARDEV(obj);
747     ChardevInfoList **list = data;
748     ChardevInfo *value = g_malloc0(sizeof(*value));
749 
750     value->label = g_strdup(chr->label);
751     value->filename = g_strdup(chr->filename);
752     value->frontend_open = chr->be && chr->be->fe_open;
753 
754     QAPI_LIST_PREPEND(*list, value);
755 
756     return 0;
757 }
758 
759 ChardevInfoList *qmp_query_chardev(Error **errp)
760 {
761     ChardevInfoList *chr_list = NULL;
762 
763     object_child_foreach(get_chardevs_root(),
764                          qmp_query_chardev_foreach, &chr_list);
765 
766     return chr_list;
767 }
768 
769 static void
770 qmp_prepend_backend(const char *name, void *opaque)
771 {
772     ChardevBackendInfoList **list = opaque;
773     ChardevBackendInfo *value;
774 
775     value = g_new0(ChardevBackendInfo, 1);
776     value->name = g_strdup(name);
777     QAPI_LIST_PREPEND(*list, value);
778 }
779 
780 ChardevBackendInfoList *qmp_query_chardev_backends(Error **errp)
781 {
782     ChardevBackendInfoList *backend_list = NULL;
783 
784     chardev_name_foreach(qmp_prepend_backend, &backend_list);
785 
786     return backend_list;
787 }
788 
789 Chardev *qemu_chr_find(const char *name)
790 {
791     Object *obj = object_resolve_path_component(get_chardevs_root(), name);
792 
793     return obj ? CHARDEV(obj) : NULL;
794 }
795 
796 QemuOptsList qemu_chardev_opts = {
797     .name = "chardev",
798     .implied_opt_name = "backend",
799     .head = QTAILQ_HEAD_INITIALIZER(qemu_chardev_opts.head),
800     .desc = {
801         {
802             .name = "backend",
803             .type = QEMU_OPT_STRING,
804         },{
805             .name = "path",
806             .type = QEMU_OPT_STRING,
807         },{
808             .name = "host",
809             .type = QEMU_OPT_STRING,
810         },{
811             .name = "port",
812             .type = QEMU_OPT_STRING,
813         },{
814             .name = "fd",
815             .type = QEMU_OPT_STRING,
816         },{
817             .name = "localaddr",
818             .type = QEMU_OPT_STRING,
819         },{
820             .name = "localport",
821             .type = QEMU_OPT_STRING,
822         },{
823             .name = "to",
824             .type = QEMU_OPT_NUMBER,
825         },{
826             .name = "ipv4",
827             .type = QEMU_OPT_BOOL,
828         },{
829             .name = "ipv6",
830             .type = QEMU_OPT_BOOL,
831         },{
832             .name = "wait",
833             .type = QEMU_OPT_BOOL,
834         },{
835             .name = "server",
836             .type = QEMU_OPT_BOOL,
837         },{
838             .name = "delay",
839             .type = QEMU_OPT_BOOL,
840         },{
841             .name = "nodelay",
842             .type = QEMU_OPT_BOOL,
843         },{
844             .name = "reconnect",
845             .type = QEMU_OPT_NUMBER,
846         },{
847             .name = "telnet",
848             .type = QEMU_OPT_BOOL,
849         },{
850             .name = "tn3270",
851             .type = QEMU_OPT_BOOL,
852         },{
853             .name = "tls-creds",
854             .type = QEMU_OPT_STRING,
855         },{
856             .name = "tls-authz",
857             .type = QEMU_OPT_STRING,
858         },{
859             .name = "websocket",
860             .type = QEMU_OPT_BOOL,
861         },{
862             .name = "width",
863             .type = QEMU_OPT_NUMBER,
864         },{
865             .name = "height",
866             .type = QEMU_OPT_NUMBER,
867         },{
868             .name = "cols",
869             .type = QEMU_OPT_NUMBER,
870         },{
871             .name = "rows",
872             .type = QEMU_OPT_NUMBER,
873         },{
874             .name = "mux",
875             .type = QEMU_OPT_BOOL,
876         },{
877             .name = "signal",
878             .type = QEMU_OPT_BOOL,
879         },{
880             .name = "name",
881             .type = QEMU_OPT_STRING,
882         },{
883             .name = "debug",
884             .type = QEMU_OPT_NUMBER,
885         },{
886             .name = "size",
887             .type = QEMU_OPT_SIZE,
888         },{
889             .name = "chardev",
890             .type = QEMU_OPT_STRING,
891         },{
892             .name = "append",
893             .type = QEMU_OPT_BOOL,
894         },{
895             .name = "logfile",
896             .type = QEMU_OPT_STRING,
897         },{
898             .name = "logappend",
899             .type = QEMU_OPT_BOOL,
900         },{
901             .name = "mouse",
902             .type = QEMU_OPT_BOOL,
903         },{
904             .name = "clipboard",
905             .type = QEMU_OPT_BOOL,
906 #ifdef CONFIG_LINUX
907         },{
908             .name = "tight",
909             .type = QEMU_OPT_BOOL,
910             .def_value_str = "on",
911         },{
912             .name = "abstract",
913             .type = QEMU_OPT_BOOL,
914 #endif
915         },
916         { /* end of list */ }
917     },
918 };
919 
920 bool qemu_chr_has_feature(Chardev *chr,
921                           ChardevFeature feature)
922 {
923     return test_bit(feature, chr->features);
924 }
925 
926 void qemu_chr_set_feature(Chardev *chr,
927                            ChardevFeature feature)
928 {
929     return set_bit(feature, chr->features);
930 }
931 
932 static Chardev *chardev_new(const char *id, const char *typename,
933                             ChardevBackend *backend,
934                             GMainContext *gcontext,
935                             bool handover_yank_instance,
936                             Error **errp)
937 {
938     Object *obj;
939     Chardev *chr = NULL;
940     Error *local_err = NULL;
941     bool be_opened = true;
942 
943     assert(g_str_has_prefix(typename, "chardev-"));
944     assert(id);
945 
946     obj = object_new(typename);
947     chr = CHARDEV(obj);
948     chr->handover_yank_instance = handover_yank_instance;
949     chr->label = g_strdup(id);
950     chr->gcontext = gcontext;
951 
952     qemu_char_open(chr, backend, &be_opened, &local_err);
953     if (local_err) {
954         error_propagate(errp, local_err);
955         object_unref(obj);
956         return NULL;
957     }
958 
959     if (!chr->filename) {
960         chr->filename = g_strdup(typename + 8);
961     }
962     if (be_opened) {
963         qemu_chr_be_event(chr, CHR_EVENT_OPENED);
964     }
965 
966     return chr;
967 }
968 
969 Chardev *qemu_chardev_new(const char *id, const char *typename,
970                           ChardevBackend *backend,
971                           GMainContext *gcontext,
972                           Error **errp)
973 {
974     Chardev *chr;
975     g_autofree char *genid = NULL;
976 
977     if (!id) {
978         genid = id_generate(ID_CHR);
979         id = genid;
980     }
981 
982     chr = chardev_new(id, typename, backend, gcontext, false, errp);
983     if (!chr) {
984         return NULL;
985     }
986 
987     if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
988                                        errp)) {
989         object_unref(OBJECT(chr));
990         return NULL;
991     }
992     object_unref(OBJECT(chr));
993 
994     return chr;
995 }
996 
997 ChardevReturn *qmp_chardev_add(const char *id, ChardevBackend *backend,
998                                Error **errp)
999 {
1000     ERRP_GUARD();
1001     const ChardevClass *cc;
1002     ChardevReturn *ret;
1003     g_autoptr(Chardev) chr = NULL;
1004 
1005     if (qemu_chr_find(id)) {
1006         error_setg(errp, "Chardev with id '%s' already exists", id);
1007         return NULL;
1008     }
1009 
1010     cc = char_get_class(ChardevBackendKind_str(backend->type), errp);
1011     if (!cc) {
1012         goto err;
1013     }
1014 
1015     chr = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc)),
1016                       backend, NULL, false, errp);
1017     if (!chr) {
1018         goto err;
1019     }
1020 
1021     if (!object_property_try_add_child(get_chardevs_root(), id, OBJECT(chr),
1022                                        errp)) {
1023         goto err;
1024     }
1025 
1026     ret = g_new0(ChardevReturn, 1);
1027     if (CHARDEV_IS_PTY(chr)) {
1028         ret->pty = g_strdup(chr->filename + 4);
1029     }
1030 
1031     return ret;
1032 
1033 err:
1034     error_prepend(errp, "Failed to add chardev '%s': ", id);
1035     return NULL;
1036 }
1037 
1038 ChardevReturn *qmp_chardev_change(const char *id, ChardevBackend *backend,
1039                                   Error **errp)
1040 {
1041     CharBackend *be;
1042     const ChardevClass *cc, *cc_new;
1043     Chardev *chr, *chr_new;
1044     bool closed_sent = false;
1045     bool handover_yank_instance;
1046     ChardevReturn *ret;
1047 
1048     chr = qemu_chr_find(id);
1049     if (!chr) {
1050         error_setg(errp, "Chardev '%s' does not exist", id);
1051         return NULL;
1052     }
1053 
1054     if (CHARDEV_IS_MUX(chr)) {
1055         error_setg(errp, "Mux device hotswap not supported yet");
1056         return NULL;
1057     }
1058 
1059     if (qemu_chr_replay(chr)) {
1060         error_setg(errp,
1061             "Chardev '%s' cannot be changed in record/replay mode", id);
1062         return NULL;
1063     }
1064 
1065     be = chr->be;
1066     if (!be) {
1067         /* easy case */
1068         object_unparent(OBJECT(chr));
1069         return qmp_chardev_add(id, backend, errp);
1070     }
1071 
1072     if (!be->chr_be_change) {
1073         error_setg(errp, "Chardev user does not support chardev hotswap");
1074         return NULL;
1075     }
1076 
1077     cc = CHARDEV_GET_CLASS(chr);
1078     cc_new = char_get_class(ChardevBackendKind_str(backend->type), errp);
1079     if (!cc_new) {
1080         return NULL;
1081     }
1082 
1083     /*
1084      * The new chardev should not register a yank instance if the current
1085      * chardev has registered one already.
1086      */
1087     handover_yank_instance = cc->supports_yank && cc_new->supports_yank;
1088 
1089     chr_new = chardev_new(id, object_class_get_name(OBJECT_CLASS(cc_new)),
1090                           backend, chr->gcontext, handover_yank_instance, errp);
1091     if (!chr_new) {
1092         return NULL;
1093     }
1094 
1095     if (chr->be_open && !chr_new->be_open) {
1096         qemu_chr_be_event(chr, CHR_EVENT_CLOSED);
1097         closed_sent = true;
1098     }
1099 
1100     chr->be = NULL;
1101     qemu_chr_fe_init(be, chr_new, &error_abort);
1102 
1103     if (be->chr_be_change(be->opaque) < 0) {
1104         error_setg(errp, "Chardev '%s' change failed", chr_new->label);
1105         chr_new->be = NULL;
1106         qemu_chr_fe_init(be, chr, &error_abort);
1107         if (closed_sent) {
1108             qemu_chr_be_event(chr, CHR_EVENT_OPENED);
1109         }
1110         object_unref(OBJECT(chr_new));
1111         return NULL;
1112     }
1113 
1114     /* change successfull, clean up */
1115     chr_new->handover_yank_instance = false;
1116 
1117     /*
1118      * When the old chardev is freed, it should not unregister the yank
1119      * instance if the new chardev needs it.
1120      */
1121     chr->handover_yank_instance = handover_yank_instance;
1122 
1123     object_unparent(OBJECT(chr));
1124     object_property_add_child(get_chardevs_root(), chr_new->label,
1125                               OBJECT(chr_new));
1126     object_unref(OBJECT(chr_new));
1127 
1128     ret = g_new0(ChardevReturn, 1);
1129     if (CHARDEV_IS_PTY(chr_new)) {
1130         ret->pty = g_strdup(chr_new->filename + 4);
1131     }
1132 
1133     return ret;
1134 }
1135 
1136 void qmp_chardev_remove(const char *id, Error **errp)
1137 {
1138     Chardev *chr;
1139 
1140     chr = qemu_chr_find(id);
1141     if (chr == NULL) {
1142         error_setg(errp, "Chardev '%s' not found", id);
1143         return;
1144     }
1145     if (qemu_chr_is_busy(chr)) {
1146         error_setg(errp, "Chardev '%s' is busy", id);
1147         return;
1148     }
1149     if (qemu_chr_replay(chr)) {
1150         error_setg(errp,
1151             "Chardev '%s' cannot be unplugged in record/replay mode", id);
1152         return;
1153     }
1154     object_unparent(OBJECT(chr));
1155 }
1156 
1157 void qmp_chardev_send_break(const char *id, Error **errp)
1158 {
1159     Chardev *chr;
1160 
1161     chr = qemu_chr_find(id);
1162     if (chr == NULL) {
1163         error_setg(errp, "Chardev '%s' not found", id);
1164         return;
1165     }
1166     qemu_chr_be_event(chr, CHR_EVENT_BREAK);
1167 }
1168 
1169 /*
1170  * Add a timeout callback for the chardev (in milliseconds), return
1171  * the GSource object created. Please use this to add timeout hook for
1172  * chardev instead of g_timeout_add() and g_timeout_add_seconds(), to
1173  * make sure the gcontext that the task bound to is correct.
1174  */
1175 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
1176                                  GSourceFunc func, void *private)
1177 {
1178     GSource *source = g_timeout_source_new(ms);
1179 
1180     assert(func);
1181     g_source_set_callback(source, func, private, NULL);
1182     g_source_attach(source, chr->gcontext);
1183 
1184     return source;
1185 }
1186 
1187 void qemu_chr_cleanup(void)
1188 {
1189     object_unparent(get_chardevs_root());
1190 }
1191 
1192 static void register_types(void)
1193 {
1194     type_register_static(&char_type_info);
1195 }
1196 
1197 type_init(register_types);
1198