chardev/char.c

   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->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);