cmd-queue.c

   1 /* $OpenBSD$ */
   2
   3 /*
   4  * Copyright (c) 2013 Nicholas Marriott <nicholas.marriott@gmail.com>
   5  *
   6  * Permission to use, copy, modify, and distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
  15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
  16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18
  19 #include <sys/types.h>
  20
  21 #include <ctype.h>
  22 #include <pwd.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <time.h>
  26 #include <unistd.h>
  27
  28 #include "tmux.h"
  29
  30 /* Command queue flags. */
  31 #define CMDQ_FIRED 0x1
  32 #define CMDQ_WAITING 0x2
  33
  34 /* Command queue item type. */
  35 enum cmdq_type {
  36         CMDQ_COMMAND,
  37         CMDQ_CALLBACK,
  38 };
  39
  40 /* Command queue item. */
  41 struct cmdq_item {
  42         char                    *name;
  43         struct cmdq_list        *queue;
  44         struct cmdq_item        *next;
  45
  46         struct client           *client;
  47         struct client           *target_client;
  48
  49         enum cmdq_type           type;
  50         u_int                    group;
  51
  52         u_int                    number;
  53         time_t                   time;
  54
  55         int                      flags;
  56
  57         struct cmdq_state       *state;
  58         struct cmd_find_state    source;
  59         struct cmd_find_state    target;
  60
  61         struct cmd_list         *cmdlist;
  62         struct cmd              *cmd;
  63
  64         cmdq_cb                  cb;
  65         void                    *data;
  66
  67         TAILQ_ENTRY(cmdq_item)   entry;
  68 };
  69 TAILQ_HEAD(cmdq_item_list, cmdq_item);
  70
  71 /*
  72  * Command queue state. This is the context for commands on the command queue.
  73  * It holds information about how the commands were fired (the key and flags),
  74  * any additional formats for the commands, and the current default target.
  75  * Multiple commands can share the same state and a command may update the
  76  * default target.
  77  */
  78 struct cmdq_state {
  79         int                      references;
  80         int                      flags;
  81
  82         struct format_tree      *formats;
  83
  84         struct key_event         event;
  85         struct cmd_find_state    current;
  86 };
  87
  88 /* Command queue. */
  89 struct cmdq_list {
  90         struct cmdq_item        *item;
  91         struct cmdq_item_list    list;
  92 };
  93
  94 /* Get command queue name. */
  95 static const char *
  96 cmdq_name(struct client *c)
  97 {
  98         static char     s[256];
  99
 100         if (c == NULL)
 101                 return ("<global>");
 102         if (c->name != NULL)
 103                 xsnprintf(s, sizeof s, "<%s>", c->name);
 104         else
 105                 xsnprintf(s, sizeof s, "<%p>", c);
 106         return (s);
 107 }
 108
 109 /* Get command queue from client. */
 110 static struct cmdq_list *
 111 cmdq_get(struct client *c)
 112 {
 113         static struct cmdq_list *global_queue;
 114
 115         if (c == NULL) {
 116                 if (global_queue == NULL)
 117                         global_queue = cmdq_new();
 118                 return (global_queue);
 119         }
 120         return (c->queue);
 121 }
 122
 123 /* Create a queue. */
 124 struct cmdq_list *
 125 cmdq_new(void)
 126 {
 127         struct cmdq_list        *queue;
 128
 129         queue = xcalloc(1, sizeof *queue);
 130         TAILQ_INIT (&queue->list);
 131         return (queue);
 132 }
 133
 134 /* Free a queue. */
 135 void
 136 cmdq_free(struct cmdq_list *queue)
 137 {
 138         if (!TAILQ_EMPTY(&queue->list))
 139                 fatalx("queue not empty");
 140         free(queue);
 141 }
 142
 143 /* Get item name. */
 144 const char *
 145 cmdq_get_name(struct cmdq_item *item)
 146 {
 147         return (item->name);
 148 }
 149
 150 /* Get item client. */
 151 struct client *
 152 cmdq_get_client(struct cmdq_item *item)
 153 {
 154         return (item->client);
 155 }
 156
 157 /* Get item target client. */
 158 struct client *
 159 cmdq_get_target_client(struct cmdq_item *item)
 160 {
 161         return (item->target_client);
 162 }
 163
 164 /* Get item state. */
 165 struct cmdq_state *
 166 cmdq_get_state(struct cmdq_item *item)
 167 {
 168         return (item->state);
 169 }
 170
 171 /* Get item target. */
 172 struct cmd_find_state *
 173 cmdq_get_target(struct cmdq_item *item)
 174 {
 175         return (&item->target);
 176 }
 177
 178 /* Get item source. */
 179 struct cmd_find_state *
 180 cmdq_get_source(struct cmdq_item *item)
 181 {
 182         return (&item->source);
 183 }
 184
 185 /* Get state event. */
 186 struct key_event *
 187 cmdq_get_event(struct cmdq_item *item)
 188 {
 189         return (&item->state->event);
 190 }
 191
 192 /* Get state current target. */
 193 struct cmd_find_state *
 194 cmdq_get_current(struct cmdq_item *item)
 195 {
 196         return (&item->state->current);
 197 }
 198
 199 /* Get state flags. */
 200 int
 201 cmdq_get_flags(struct cmdq_item *item)
 202 {
 203         return (item->state->flags);
 204 }
 205
 206 /* Create a new state. */
 207 struct cmdq_state *
 208 cmdq_new_state(struct cmd_find_state *current, struct key_event *event,
 209     int flags)
 210 {
 211         struct cmdq_state       *state;
 212
 213         state = xcalloc(1, sizeof *state);
 214         state->references = 1;
 215         state->flags = flags;
 216
 217         if (event != NULL)
 218                 memcpy(&state->event, event, sizeof state->event);
 219         else
 220                 state->event.key = KEYC_NONE;
 221         if (current != NULL && cmd_find_valid_state(current))
 222                 cmd_find_copy_state(&state->current, current);
 223         else
 224                 cmd_find_clear_state(&state->current, 0);
 225
 226         return (state);
 227 }
 228
 229 /* Add a reference to a state. */
 230 struct cmdq_state *
 231 cmdq_link_state(struct cmdq_state *state)
 232 {
 233         state->references++;
 234         return (state);
 235 }
 236
 237 /* Make a copy of a state. */
 238 struct cmdq_state *
 239 cmdq_copy_state(struct cmdq_state *state)
 240 {
 241         return (cmdq_new_state(&state->current, &state->event, state->flags));
 242 }
 243
 244 /* Free a state. */
 245 void
 246 cmdq_free_state(struct cmdq_state *state)
 247 {
 248         if (--state->references != 0)
 249                 return;
 250
 251         if (state->formats != NULL)
 252                 format_free(state->formats);
 253         free(state);
 254 }
 255
 256 /* Add a format to command queue. */
 257 void
 258 cmdq_add_format(struct cmdq_state *state, const char *key, const char *fmt, ...)
 259 {
 260         va_list  ap;
 261         char    *value;
 262
 263         va_start(ap, fmt);
 264         xvasprintf(&value, fmt, ap);
 265         va_end(ap);
 266
 267         if (state->formats == NULL)
 268                 state->formats = format_create(NULL, NULL, FORMAT_NONE, 0);
 269         format_add(state->formats, key, "%s", value);
 270
 271         free(value);
 272 }
 273
 274 /* Add formats to command queue. */
 275 void
 276 cmdq_add_formats(struct cmdq_state *state, struct format_tree *ft)
 277 {
 278         if (state->formats == NULL)
 279                 state->formats = format_create(NULL, NULL, FORMAT_NONE, 0);
 280         format_merge(state->formats, ft);
 281 }
 282
 283 /* Merge formats from item. */
 284 void
 285 cmdq_merge_formats(struct cmdq_item *item, struct format_tree *ft)
 286 {
 287         const struct cmd_entry  *entry;
 288
 289         if (item->cmd != NULL) {
 290                 entry = cmd_get_entry(item->cmd);
 291                 format_add(ft, "command", "%s", entry->name);
 292         }
 293         if (item->state->formats != NULL)
 294                 format_merge(ft, item->state->formats);
 295 }
 296
 297 /* Append an item. */
 298 struct cmdq_item *
 299 cmdq_append(struct client *c, struct cmdq_item *item)
 300 {
 301         struct cmdq_list        *queue = cmdq_get(c);
 302         struct cmdq_item        *next;
 303
 304         do {
 305                 next = item->next;
 306                 item->next = NULL;
 307
 308                 if (c != NULL)
 309                         c->references++;
 310                 item->client = c;
 311
 312                 item->queue = queue;
 313                 TAILQ_INSERT_TAIL(&queue->list, item, entry);
 314                 log_debug("%s %s: %s", __func__, cmdq_name(c), item->name);
 315
 316                 item = next;
 317         } while (item != NULL);
 318         return (TAILQ_LAST(&queue->list, cmdq_item_list));
 319 }
 320
 321 /* Insert an item. */
 322 struct cmdq_item *
 323 cmdq_insert_after(struct cmdq_item *after, struct cmdq_item *item)
 324 {
 325         struct client           *c = after->client;
 326         struct cmdq_list        *queue = after->queue;
 327         struct cmdq_item        *next;
 328
 329         do {
 330                 next = item->next;
 331                 item->next = after->next;
 332                 after->next = item;
 333
 334                 if (c != NULL)
 335                         c->references++;
 336                 item->client = c;
 337
 338                 item->queue = queue;
 339                 TAILQ_INSERT_AFTER(&queue->list, after, item, entry);
 340                 log_debug("%s %s: %s after %s", __func__, cmdq_name(c),
 341                     item->name, after->name);
 342
 343                 after = item;
 344                 item = next;
 345         } while (item != NULL);
 346         return (after);
 347 }
 348
 349 /* Insert a hook. */
 350 void
 351 cmdq_insert_hook(struct session *s, struct cmdq_item *item,
 352     struct cmd_find_state *current, const char *fmt, ...)
 353 {
 354         struct cmdq_state               *state = item->state;
 355         struct cmd                      *cmd = item->cmd;
 356         struct args                     *args = cmd_get_args(cmd);
 357         struct args_entry               *ae;
 358         struct args_value               *av;
 359         struct options                  *oo;
 360         va_list                          ap;
 361         char                            *name, tmp[32], flag, *arguments;
 362         u_int                            i;
 363         const char                      *value;
 364         struct cmdq_item                *new_item;
 365         struct cmdq_state               *new_state;
 366         struct options_entry            *o;
 367         struct options_array_item       *a;
 368         struct cmd_list                 *cmdlist;
 369
 370         if (item->state->flags & CMDQ_STATE_NOHOOKS)
 371                 return;
 372         if (s == NULL)
 373                 oo = global_s_options;
 374         else
 375                 oo = s->options;
 376
 377         va_start(ap, fmt);
 378         xvasprintf(&name, fmt, ap);
 379         va_end(ap);
 380
 381         o = options_get(oo, name);
 382         if (o == NULL) {
 383                 free(name);
 384                 return;
 385         }
 386         log_debug("running hook %s (parent %p)", name, item);
 387
 388         /*
 389          * The hooks get a new state because they should not update the current
 390          * target or formats for any subsequent commands.
 391          */
 392         new_state = cmdq_new_state(current, &state->event, CMDQ_STATE_NOHOOKS);
 393         cmdq_add_format(new_state, "hook", "%s", name);
 394
 395         arguments = args_print(args);
 396         cmdq_add_format(new_state, "hook_arguments", "%s", arguments);
 397         free(arguments);
 398
 399         for (i = 0; i < args_count(args); i++) {
 400                 xsnprintf(tmp, sizeof tmp, "hook_argument_%d", i);
 401                 cmdq_add_format(new_state, tmp, "%s", args_string(args, i));
 402         }
 403         flag = args_first(args, &ae);
 404         while (flag != 0) {
 405                 value = args_get(args, flag);
 406                 if (value == NULL) {
 407                         xsnprintf(tmp, sizeof tmp, "hook_flag_%c", flag);
 408                         cmdq_add_format(new_state, tmp, "1");
 409                 } else {
 410                         xsnprintf(tmp, sizeof tmp, "hook_flag_%c", flag);
 411                         cmdq_add_format(new_state, tmp, "%s", value);
 412                 }
 413
 414                 i = 0;
 415                 av = args_first_value(args, flag);
 416                 while (av != NULL) {
 417                         xsnprintf(tmp, sizeof tmp, "hook_flag_%c_%d", flag, i);
 418                         cmdq_add_format(new_state, tmp, "%s", av->string);
 419                         i++;
 420                         av = args_next_value(av);
 421                 }
 422
 423                 flag = args_next(&ae);
 424         }
 425
 426         a = options_array_first(o);
 427         while (a != NULL) {
 428                 cmdlist = options_array_item_value(a)->cmdlist;
 429                 if (cmdlist != NULL) {
 430                         new_item = cmdq_get_command(cmdlist, new_state);
 431                         if (item != NULL)
 432                                 item = cmdq_insert_after(item, new_item);
 433                         else
 434                                 item = cmdq_append(NULL, new_item);
 435                 }
 436                 a = options_array_next(a);
 437         }
 438
 439         cmdq_free_state(new_state);
 440         free(name);
 441 }
 442
 443 /* Continue processing command queue. */
 444 void
 445 cmdq_continue(struct cmdq_item *item)
 446 {
 447         item->flags &= ~CMDQ_WAITING;
 448 }
 449
 450 /* Remove an item. */
 451 static void
 452 cmdq_remove(struct cmdq_item *item)
 453 {
 454         if (item->client != NULL)
 455                 server_client_unref(item->client);
 456         if (item->cmdlist != NULL)
 457                 cmd_list_free(item->cmdlist);
 458         cmdq_free_state(item->state);
 459
 460         TAILQ_REMOVE(&item->queue->list, item, entry);
 461
 462         free(item->name);
 463         free(item);
 464 }
 465
 466 /* Remove all subsequent items that match this item's group. */
 467 static void
 468 cmdq_remove_group(struct cmdq_item *item)
 469 {
 470         struct cmdq_item        *this, *next;
 471
 472         if (item->group == 0)
 473                 return;
 474         this = TAILQ_NEXT(item, entry);
 475         while (this != NULL) {
 476                 next = TAILQ_NEXT(this, entry);
 477                 if (this->group == item->group)
 478                         cmdq_remove(this);
 479                 this = next;
 480         }
 481 }
 482
 483 /* Empty command callback. */
 484 static enum cmd_retval
 485 cmdq_empty_command(__unused struct cmdq_item *item, __unused void *data)
 486 {
 487         return (CMD_RETURN_NORMAL);
 488 }
 489
 490 /* Get a command for the command queue. */
 491 struct cmdq_item *
 492 cmdq_get_command(struct cmd_list *cmdlist, struct cmdq_state *state)
 493 {
 494         struct cmdq_item        *item, *first = NULL, *last = NULL;
 495         struct cmd              *cmd;
 496         const struct cmd_entry  *entry;
 497         int                      created = 0;
 498
 499         if ((cmd = cmd_list_first(cmdlist)) == NULL)
 500                 return (cmdq_get_callback(cmdq_empty_command, NULL));
 501
 502         if (state == NULL) {
 503                 state = cmdq_new_state(NULL, NULL, 0);
 504                 created = 1;
 505         }
 506
 507         while (cmd != NULL) {
 508                 entry = cmd_get_entry(cmd);
 509
 510                 item = xcalloc(1, sizeof *item);
 511                 xasprintf(&item->name, "[%s/%p]", entry->name, item);
 512                 item->type = CMDQ_COMMAND;
 513
 514                 item->group = cmd_get_group(cmd);
 515                 item->state = cmdq_link_state(state);
 516
 517                 item->cmdlist = cmdlist;
 518                 item->cmd = cmd;
 519
 520                 cmdlist->references++;
 521                 log_debug("%s: %s group %u", __func__, item->name, item->group);
 522
 523                 if (first == NULL)
 524                         first = item;
 525                 if (last != NULL)
 526                         last->next = item;
 527                 last = item;
 528
 529                 cmd = cmd_list_next(cmd);
 530         }
 531
 532         if (created)
 533                 cmdq_free_state(state);
 534         return (first);
 535 }
 536
 537 /* Fill in flag for a command. */
 538 static enum cmd_retval
 539 cmdq_find_flag(struct cmdq_item *item, struct cmd_find_state *fs,
 540     const struct cmd_entry_flag *flag)
 541 {
 542         const char      *value;
 543
 544         if (flag->flag == 0) {
 545                 cmd_find_from_client(fs, item->target_client, 0);
 546                 return (CMD_RETURN_NORMAL);
 547         }
 548
 549         value = args_get(cmd_get_args(item->cmd), flag->flag);
 550         if (cmd_find_target(fs, item, value, flag->type, flag->flags) != 0) {
 551                 cmd_find_clear_state(fs, 0);
 552                 return (CMD_RETURN_ERROR);
 553         }
 554         return (CMD_RETURN_NORMAL);
 555 }
 556
 557 /* Add message with command. */
 558 static void
 559 cmdq_add_message(struct cmdq_item *item)
 560 {
 561         struct client           *c = item->client;
 562         struct cmdq_state       *state = item->state;
 563         const char              *key;
 564         char                    *tmp;
 565         uid_t                    uid;
 566         struct passwd           *pw;
 567         char                    *user = NULL;
 568
 569         tmp = cmd_print(item->cmd);
 570         if (c != NULL) {
 571                 uid = proc_get_peer_uid(c->peer);
 572                 if (uid != (uid_t)-1 && uid != getuid()) {
 573                         if ((pw = getpwuid(uid)) != NULL)
 574                                 xasprintf(&user, "[%s]", pw->pw_name);
 575                         else
 576                                 user = xstrdup("[unknown]");
 577                 } else
 578                         user = xstrdup("");
 579                 if (c->session != NULL && state->event.key != KEYC_NONE) {
 580                         key = key_string_lookup_key(state->event.key, 0);
 581                         server_add_message("%s%s key %s: %s", c->name, user,
 582                             key, tmp);
 583                 } else {
 584                         server_add_message("%s%s command: %s", c->name, user,
 585                             tmp);
 586                 }
 587                 free(user);
 588         } else
 589                 server_add_message("command: %s", tmp);
 590         free(tmp);
 591 }
 592
 593 /* Fire command on command queue. */
 594 static enum cmd_retval
 595 cmdq_fire_command(struct cmdq_item *item)
 596 {
 597         const char              *name = cmdq_name(item->client);
 598         struct cmdq_state       *state = item->state;
 599         struct cmd              *cmd = item->cmd;
 600         struct args             *args = cmd_get_args(cmd);
 601         const struct cmd_entry  *entry = cmd_get_entry(cmd);
 602         struct client           *tc, *saved = item->client;
 603         enum cmd_retval          retval;
 604         struct cmd_find_state   *fsp, fs;
 605         int                      flags, quiet = 0;
 606         char                    *tmp;
 607
 608         if (cfg_finished)
 609                 cmdq_add_message(item);
 610         if (log_get_level() > 1) {
 611                 tmp = cmd_print(cmd);
 612                 log_debug("%s %s: (%u) %s", __func__, name, item->group, tmp);
 613                 free(tmp);
 614         }
 615
 616         flags = !!(state->flags & CMDQ_STATE_CONTROL);
 617         cmdq_guard(item, "begin", flags);
 618
 619         if (item->client == NULL)
 620                 item->client = cmd_find_client(item, NULL, 1);
 621
 622         if (entry->flags & CMD_CLIENT_CANFAIL)
 623                 quiet = 1;
 624         if (entry->flags & CMD_CLIENT_CFLAG) {
 625                 tc = cmd_find_client(item, args_get(args, 'c'), quiet);
 626                 if (tc == NULL && !quiet) {
 627                         retval = CMD_RETURN_ERROR;
 628                         goto out;
 629                 }
 630         } else if (entry->flags & CMD_CLIENT_TFLAG) {
 631                 tc = cmd_find_client(item, args_get(args, 't'), quiet);
 632                 if (tc == NULL && !quiet) {
 633                         retval = CMD_RETURN_ERROR;
 634                         goto out;
 635                 }
 636         } else
 637                 tc = cmd_find_client(item, NULL, 1);
 638         item->target_client = tc;
 639
 640         retval = cmdq_find_flag(item, &item->source, &entry->source);
 641         if (retval == CMD_RETURN_ERROR)
 642                 goto out;
 643         retval = cmdq_find_flag(item, &item->target, &entry->target);
 644         if (retval == CMD_RETURN_ERROR)
 645                 goto out;
 646
 647         retval = entry->exec(cmd, item);
 648         if (retval == CMD_RETURN_ERROR)
 649                 goto out;
 650
 651         if (entry->flags & CMD_AFTERHOOK) {
 652                 if (cmd_find_valid_state(&item->target))
 653                         fsp = &item->target;
 654                 else if (cmd_find_valid_state(&item->state->current))
 655                         fsp = &item->state->current;
 656                 else if (cmd_find_from_client(&fs, item->client, 0) == 0)
 657                         fsp = &fs;
 658                 else
 659                         goto out;
 660                 cmdq_insert_hook(fsp->s, item, fsp, "after-%s", entry->name);
 661         }
 662
 663 out:
 664         item->client = saved;
 665         if (retval == CMD_RETURN_ERROR)
 666                 cmdq_guard(item, "error", flags);
 667         else
 668                 cmdq_guard(item, "end", flags);
 669         return (retval);
 670 }
 671
 672 /* Get a callback for the command queue. */
 673 struct cmdq_item *
 674 cmdq_get_callback1(const char *name, cmdq_cb cb, void *data)
 675 {
 676         struct cmdq_item        *item;
 677
 678         item = xcalloc(1, sizeof *item);
 679         xasprintf(&item->name, "[%s/%p]", name, item);
 680         item->type = CMDQ_CALLBACK;
 681
 682         item->group = 0;
 683         item->state = cmdq_new_state(NULL, NULL, 0);
 684
 685         item->cb = cb;
 686         item->data = data;
 687
 688         return (item);
 689 }
 690
 691 /* Generic error callback. */
 692 static enum cmd_retval
 693 cmdq_error_callback(struct cmdq_item *item, void *data)
 694 {
 695         char    *error = data;
 696
 697         cmdq_error(item, "%s", error);
 698         free(error);
 699
 700         return (CMD_RETURN_NORMAL);
 701 }
 702
 703 /* Get an error callback for the command queue. */
 704 struct cmdq_item *
 705 cmdq_get_error(const char *error)
 706 {
 707         return (cmdq_get_callback(cmdq_error_callback, xstrdup(error)));
 708 }
 709
 710 /* Fire callback on callback queue. */
 711 static enum cmd_retval
 712 cmdq_fire_callback(struct cmdq_item *item)
 713 {
 714         return (item->cb(item, item->data));
 715 }
 716
 717 /* Process next item on command queue. */
 718 u_int
 719 cmdq_next(struct client *c)
 720 {
 721         struct cmdq_list        *queue = cmdq_get(c);
 722         const char              *name = cmdq_name(c);
 723         struct cmdq_item        *item;
 724         enum cmd_retval          retval;
 725         u_int                    items = 0;
 726         static u_int             number;
 727
 728         if (TAILQ_EMPTY(&queue->list)) {
 729                 log_debug("%s %s: empty", __func__, name);
 730                 return (0);
 731         }
 732         if (TAILQ_FIRST(&queue->list)->flags & CMDQ_WAITING) {
 733                 log_debug("%s %s: waiting", __func__, name);
 734                 return (0);
 735         }
 736
 737         log_debug("%s %s: enter", __func__, name);
 738         for (;;) {
 739                 item = queue->item = TAILQ_FIRST(&queue->list);
 740                 if (item == NULL)
 741                         break;
 742                 log_debug("%s %s: %s (%d), flags %x", __func__, name,
 743                     item->name, item->type, item->flags);
 744
 745                 /*
 746                  * Any item with the waiting flag set waits until an external
 747                  * event clears the flag (for example, a job - look at
 748                  * run-shell).
 749                  */
 750                 if (item->flags & CMDQ_WAITING)
 751                         goto waiting;
 752
 753                 /*
 754                  * Items are only fired once, once the fired flag is set, a
 755                  * waiting flag can only be cleared by an external event.
 756                  */
 757                 if (~item->flags & CMDQ_FIRED) {
 758                         item->time = time(NULL);
 759                         item->number = ++number;
 760
 761                         switch (item->type) {
 762                         case CMDQ_COMMAND:
 763                                 retval = cmdq_fire_command(item);
 764
 765                                 /*
 766                                  * If a command returns an error, remove any
 767                                  * subsequent commands in the same group.
 768                                  */
 769                                 if (retval == CMD_RETURN_ERROR)
 770                                         cmdq_remove_group(item);
 771                                 break;
 772                         case CMDQ_CALLBACK:
 773                                 retval = cmdq_fire_callback(item);
 774                                 break;
 775                         default:
 776                                 retval = CMD_RETURN_ERROR;
 777                                 break;
 778                         }
 779                         item->flags |= CMDQ_FIRED;
 780
 781                         if (retval == CMD_RETURN_WAIT) {
 782                                 item->flags |= CMDQ_WAITING;
 783                                 goto waiting;
 784                         }
 785                         items++;
 786                 }
 787                 cmdq_remove(item);
 788         }
 789         queue->item = NULL;
 790
 791         log_debug("%s %s: exit (empty)", __func__, name);
 792         return (items);
 793
 794 waiting:
 795         log_debug("%s %s: exit (wait)", __func__, name);
 796         return (items);
 797 }
 798
 799 /* Get running item if any. */
 800 struct cmdq_item *
 801 cmdq_running(struct client *c)
 802 {
 803         struct cmdq_list        *queue = cmdq_get(c);
 804
 805         if (queue->item == NULL)
 806         return (NULL);
 807     if (queue->item->flags & CMDQ_WAITING)
 808         return (NULL);
 809     return (queue->item);
 810 }
 811
 812 /* Print a guard line. */
 813 void
 814 cmdq_guard(struct cmdq_item *item, const char *guard, int flags)
 815 {
 816         struct client   *c = item->client;
 817         long             t = item->time;
 818         u_int            number = item->number;
 819
 820         if (c != NULL && (c->flags & CLIENT_CONTROL))
 821                 control_write(c, "%%%s %ld %u %d", guard, t, number, flags);
 822 }
 823
 824 /* Show message from command. */
 825 void
 826 cmdq_print(struct cmdq_item *item, const char *fmt, ...)
 827 {
 828         struct client                   *c = item->client;
 829         struct window_pane              *wp;
 830         struct window_mode_entry        *wme;
 831         va_list                          ap;
 832         char                            *tmp, *msg;
 833
 834         va_start(ap, fmt);
 835         xvasprintf(&msg, fmt, ap);
 836         va_end(ap);
 837
 838         log_debug("%s: %s", __func__, msg);
 839
 840         if (c == NULL)
 841                 /* nothing */;
 842         else if (c->session == NULL || (c->flags & CLIENT_CONTROL)) {
 843                 if (~c->flags & CLIENT_UTF8) {
 844                         tmp = msg;
 845                         msg = utf8_sanitize(tmp);
 846                         free(tmp);
 847                 }
 848                 if (c->flags & CLIENT_CONTROL)
 849                         control_write(c, "%s", msg);
 850                 else
 851                         file_print(c, "%s\n", msg);
 852         } else {
 853                 wp = server_client_get_pane(c);
 854                 wme = TAILQ_FIRST(&wp->modes);
 855                 if (wme == NULL || wme->mode != &window_view_mode) {
 856                         window_pane_set_mode(wp, NULL, &window_view_mode, NULL,
 857                             NULL);
 858                 }
 859                 window_copy_add(wp, 0, "%s", msg);
 860         }
 861
 862         free(msg);
 863 }
 864
 865 /* Show error from command. */
 866 void
 867 cmdq_error(struct cmdq_item *item, const char *fmt, ...)
 868 {
 869         struct client   *c = item->client;
 870         struct cmd      *cmd = item->cmd;
 871         va_list          ap;
 872         char            *msg, *tmp;
 873         const char      *file;
 874         u_int            line;
 875
 876         va_start(ap, fmt);
 877         xvasprintf(&msg, fmt, ap);
 878         va_end(ap);
 879
 880         log_debug("%s: %s", __func__, msg);
 881
 882         if (c == NULL) {
 883                 cmd_get_source(cmd, &file, &line);
 884                 cfg_add_cause("%s:%u: %s", file, line, msg);
 885         } else if (c->session == NULL || (c->flags & CLIENT_CONTROL)) {
 886                 server_add_message("%s message: %s", c->name, msg);
 887                 if (~c->flags & CLIENT_UTF8) {
 888                         tmp = msg;
 889                         msg = utf8_sanitize(tmp);
 890                         free(tmp);
 891                 }
 892                 if (c->flags & CLIENT_CONTROL)
 893                         control_write(c, "%s", msg);
 894                 else
 895                         file_error(c, "%s\n", msg);
 896                 c->retval = 1;
 897         } else {
 898                 *msg = toupper((u_char) *msg);
 899                 status_message_set(c, -1, 1, 0, "%s", msg);
 900         }
 901
 902         free(msg);
 903 }