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