session.c

   1 /* $OpenBSD$ */
   2
   3 /*
   4  * Copyright (c) 2007 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 #include <sys/time.h>
  21
  22 #include <paths.h>
  23 #include <string.h>
  24 #include <stdlib.h>
  25 #include <unistd.h>
  26 #include <vis.h>
  27 #include <time.h>
  28
  29 #include "tmux.h"
  30
  31 struct sessions         sessions;
  32 u_int                   next_session_id;
  33 struct session_groups   session_groups = RB_INITIALIZER(&session_groups);
  34
  35 static void     session_free(int, short, void *);
  36
  37 static void     session_lock_timer(int, short, void *);
  38
  39 static struct winlink *session_next_alert(struct winlink *);
  40 static struct winlink *session_previous_alert(struct winlink *);
  41
  42 static void     session_group_remove(struct session *);
  43 static void     session_group_synchronize1(struct session *, struct session *);
  44
  45 int
  46 session_cmp(struct session *s1, struct session *s2)
  47 {
  48         return (strcmp(s1->name, s2->name));
  49 }
  50 RB_GENERATE(sessions, session, entry, session_cmp);
  51
  52 static int
  53 session_group_cmp(struct session_group *s1, struct session_group *s2)
  54 {
  55         return (strcmp(s1->name, s2->name));
  56 }
  57 RB_GENERATE_STATIC(session_groups, session_group, entry, session_group_cmp);
  58
  59 /*
  60  * Find if session is still alive. This is true if it is still on the global
  61  * sessions list.
  62  */
  63 int
  64 session_alive(struct session *s)
  65 {
  66         struct session *s_loop;
  67
  68         RB_FOREACH(s_loop, sessions, &sessions) {
  69                 if (s_loop == s)
  70                         return (1);
  71         }
  72         return (0);
  73 }
  74
  75 /* Find session by name. */
  76 struct session *
  77 session_find(const char *name)
  78 {
  79         struct session  s;
  80
  81         s.name = (char *) name;
  82         return (RB_FIND(sessions, &sessions, &s));
  83 }
  84
  85 /* Find session by id parsed from a string. */
  86 struct session *
  87 session_find_by_id_str(const char *s)
  88 {
  89         const char      *errstr;
  90         u_int            id;
  91
  92         if (*s != '$')
  93                 return (NULL);
  94
  95         id = strtonum(s + 1, 0, UINT_MAX, &errstr);
  96         if (errstr != NULL)
  97                 return (NULL);
  98         return (session_find_by_id(id));
  99 }
 100
 101 /* Find session by id. */
 102 struct session *
 103 session_find_by_id(u_int id)
 104 {
 105         struct session  *s;
 106
 107         RB_FOREACH(s, sessions, &sessions) {
 108                 if (s->id == id)
 109                         return (s);
 110         }
 111         return (NULL);
 112 }
 113
 114 /* Create a new session. */
 115 struct session *
 116 session_create(const char *prefix, const char *name, const char *cwd,
 117     struct environ *env, struct options *oo, struct termios *tio)
 118 {
 119         struct session  *s;
 120
 121         s = xcalloc(1, sizeof *s);
 122         s->references = 1;
 123         s->flags = 0;
 124
 125         s->cwd = xstrdup(cwd);
 126
 127         TAILQ_INIT(&s->lastw);
 128         RB_INIT(&s->windows);
 129
 130         s->environ = env;
 131         s->options = oo;
 132
 133         status_update_cache(s);
 134
 135         s->tio = NULL;
 136         if (tio != NULL) {
 137                 s->tio = xmalloc(sizeof *s->tio);
 138                 memcpy(s->tio, tio, sizeof *s->tio);
 139         }
 140
 141         if (name != NULL) {
 142                 s->name = xstrdup(name);
 143                 s->id = next_session_id++;
 144         } else {
 145                 do {
 146                         s->id = next_session_id++;
 147                         free(s->name);
 148                         if (prefix != NULL)
 149                                 xasprintf(&s->name, "%s-%u", prefix, s->id);
 150                         else
 151                                 xasprintf(&s->name, "%u", s->id);
 152                 } while (RB_FIND(sessions, &sessions, s) != NULL);
 153         }
 154         RB_INSERT(sessions, &sessions, s);
 155
 156         log_debug("new session %s $%u", s->name, s->id);
 157
 158         if (gettimeofday(&s->creation_time, NULL) != 0)
 159                 fatal("gettimeofday failed");
 160         session_update_activity(s, &s->creation_time);
 161
 162         return (s);
 163 }
 164
 165 /* Add a reference to a session. */
 166 void
 167 session_add_ref(struct session *s, const char *from)
 168 {
 169         s->references++;
 170         log_debug("%s: %s %s, now %d", __func__, s->name, from, s->references);
 171 }
 172
 173 /* Remove a reference from a session. */
 174 void
 175 session_remove_ref(struct session *s, const char *from)
 176 {
 177         s->references--;
 178         log_debug("%s: %s %s, now %d", __func__, s->name, from, s->references);
 179
 180         if (s->references == 0)
 181                 event_once(-1, EV_TIMEOUT, session_free, s, NULL);
 182 }
 183
 184 /* Free session. */
 185 static void
 186 session_free(__unused int fd, __unused short events, void *arg)
 187 {
 188         struct session  *s = arg;
 189
 190         log_debug("session %s freed (%d references)", s->name, s->references);
 191
 192         if (s->references == 0) {
 193                 environ_free(s->environ);
 194                 options_free(s->options);
 195
 196                 free(s->name);
 197                 free(s);
 198         }
 199 }
 200
 201 /* Destroy a session. */
 202 void
 203 session_destroy(struct session *s, int notify, const char *from)
 204 {
 205         struct winlink  *wl;
 206
 207         log_debug("session %s destroyed (%s)", s->name, from);
 208
 209         if (s->curw == NULL)
 210                 return;
 211         s->curw = NULL;
 212
 213         RB_REMOVE(sessions, &sessions, s);
 214         if (notify)
 215                 notify_session("session-closed", s);
 216
 217         free(s->tio);
 218
 219         if (event_initialized(&s->lock_timer))
 220                 event_del(&s->lock_timer);
 221
 222         session_group_remove(s);
 223
 224         while (!TAILQ_EMPTY(&s->lastw))
 225                 winlink_stack_remove(&s->lastw, TAILQ_FIRST(&s->lastw));
 226         while (!RB_EMPTY(&s->windows)) {
 227                 wl = RB_ROOT(&s->windows);
 228                 notify_session_window("window-unlinked", s, wl->window);
 229                 winlink_remove(&s->windows, wl);
 230         }
 231
 232         free((void *)s->cwd);
 233
 234         session_remove_ref(s, __func__);
 235 }
 236
 237 /* Sanitize session name. */
 238 char *
 239 session_check_name(const char *name)
 240 {
 241         char    *copy, *cp, *new_name;
 242
 243         if (*name == '\0')
 244                 return (NULL);
 245         copy = xstrdup(name);
 246         for (cp = copy; *cp != '\0'; cp++) {
 247                 if (*cp == ':' || *cp == '.')
 248                         *cp = '_';
 249         }
 250         utf8_stravis(&new_name, copy, VIS_OCTAL|VIS_CSTYLE|VIS_TAB|VIS_NL);
 251         free(copy);
 252         return (new_name);
 253 }
 254
 255 /* Lock session if it has timed out. */
 256 static void
 257 session_lock_timer(__unused int fd, __unused short events, void *arg)
 258 {
 259         struct session  *s = arg;
 260
 261         if (s->attached == 0)
 262                 return;
 263
 264         log_debug("session %s locked, activity time %lld", s->name,
 265             (long long)s->activity_time.tv_sec);
 266
 267         server_lock_session(s);
 268         recalculate_sizes();
 269 }
 270
 271 /* Update activity time. */
 272 void
 273 session_update_activity(struct session *s, struct timeval *from)
 274 {
 275         struct timeval   tv;
 276
 277         if (from == NULL)
 278                 gettimeofday(&s->activity_time, NULL);
 279         else
 280                 memcpy(&s->activity_time, from, sizeof s->activity_time);
 281
 282         log_debug("session $%u %s activity %lld.%06d", s->id,
 283             s->name, (long long)s->activity_time.tv_sec,
 284             (int)s->activity_time.tv_usec);
 285
 286         if (evtimer_initialized(&s->lock_timer))
 287                 evtimer_del(&s->lock_timer);
 288         else
 289                 evtimer_set(&s->lock_timer, session_lock_timer, s);
 290
 291         if (s->attached != 0) {
 292                 timerclear(&tv);
 293                 tv.tv_sec = options_get_number(s->options, "lock-after-time");
 294                 if (tv.tv_sec != 0)
 295                         evtimer_add(&s->lock_timer, &tv);
 296         }
 297 }
 298
 299 /* Find the next usable session. */
 300 struct session *
 301 session_next_session(struct session *s)
 302 {
 303         struct session *s2;
 304
 305         if (RB_EMPTY(&sessions) || !session_alive(s))
 306                 return (NULL);
 307
 308         s2 = RB_NEXT(sessions, &sessions, s);
 309         if (s2 == NULL)
 310                 s2 = RB_MIN(sessions, &sessions);
 311         if (s2 == s)
 312                 return (NULL);
 313         return (s2);
 314 }
 315
 316 /* Find the previous usable session. */
 317 struct session *
 318 session_previous_session(struct session *s)
 319 {
 320         struct session *s2;
 321
 322         if (RB_EMPTY(&sessions) || !session_alive(s))
 323                 return (NULL);
 324
 325         s2 = RB_PREV(sessions, &sessions, s);
 326         if (s2 == NULL)
 327                 s2 = RB_MAX(sessions, &sessions);
 328         if (s2 == s)
 329                 return (NULL);
 330         return (s2);
 331 }
 332
 333 /* Attach a window to a session. */
 334 struct winlink *
 335 session_attach(struct session *s, struct window *w, int idx, char **cause)
 336 {
 337         struct winlink  *wl;
 338
 339         if ((wl = winlink_add(&s->windows, idx)) == NULL) {
 340                 xasprintf(cause, "index in use: %d", idx);
 341                 return (NULL);
 342         }
 343         wl->session = s;
 344         winlink_set_window(wl, w);
 345         notify_session_window("window-linked", s, w);
 346
 347         session_group_synchronize_from(s);
 348         return (wl);
 349 }
 350
 351 /* Detach a window from a session. */
 352 int
 353 session_detach(struct session *s, struct winlink *wl)
 354 {
 355         if (s->curw == wl &&
 356             session_last(s) != 0 &&
 357             session_previous(s, 0) != 0)
 358                 session_next(s, 0);
 359
 360         wl->flags &= ~WINLINK_ALERTFLAGS;
 361         notify_session_window("window-unlinked", s, wl->window);
 362         winlink_stack_remove(&s->lastw, wl);
 363         winlink_remove(&s->windows, wl);
 364
 365         session_group_synchronize_from(s);
 366
 367         if (RB_EMPTY(&s->windows))
 368                 return (1);
 369         return (0);
 370 }
 371
 372 /* Return if session has window. */
 373 int
 374 session_has(struct session *s, struct window *w)
 375 {
 376         struct winlink  *wl;
 377
 378         TAILQ_FOREACH(wl, &w->winlinks, wentry) {
 379                 if (wl->session == s)
 380                         return (1);
 381         }
 382         return (0);
 383 }
 384
 385 /*
 386  * Return 1 if a window is linked outside this session (not including session
 387  * groups). The window must be in this session!
 388  */
 389 int
 390 session_is_linked(struct session *s, struct window *w)
 391 {
 392         struct session_group    *sg;
 393
 394         if ((sg = session_group_contains(s)) != NULL)
 395                 return (w->references != session_group_count(sg));
 396         return (w->references != 1);
 397 }
 398
 399 static struct winlink *
 400 session_next_alert(struct winlink *wl)
 401 {
 402         while (wl != NULL) {
 403                 if (wl->flags & WINLINK_ALERTFLAGS)
 404                         break;
 405                 wl = winlink_next(wl);
 406         }
 407         return (wl);
 408 }
 409
 410 /* Move session to next window. */
 411 int
 412 session_next(struct session *s, int alert)
 413 {
 414         struct winlink  *wl;
 415
 416         if (s->curw == NULL)
 417                 return (-1);
 418
 419         wl = winlink_next(s->curw);
 420         if (alert)
 421                 wl = session_next_alert(wl);
 422         if (wl == NULL) {
 423                 wl = RB_MIN(winlinks, &s->windows);
 424                 if (alert && ((wl = session_next_alert(wl)) == NULL))
 425                         return (-1);
 426         }
 427         return (session_set_current(s, wl));
 428 }
 429
 430 static struct winlink *
 431 session_previous_alert(struct winlink *wl)
 432 {
 433         while (wl != NULL) {
 434                 if (wl->flags & WINLINK_ALERTFLAGS)
 435                         break;
 436                 wl = winlink_previous(wl);
 437         }
 438         return (wl);
 439 }
 440
 441 /* Move session to previous window. */
 442 int
 443 session_previous(struct session *s, int alert)
 444 {
 445         struct winlink  *wl;
 446
 447         if (s->curw == NULL)
 448                 return (-1);
 449
 450         wl = winlink_previous(s->curw);
 451         if (alert)
 452                 wl = session_previous_alert(wl);
 453         if (wl == NULL) {
 454                 wl = RB_MAX(winlinks, &s->windows);
 455                 if (alert && (wl = session_previous_alert(wl)) == NULL)
 456                         return (-1);
 457         }
 458         return (session_set_current(s, wl));
 459 }
 460
 461 /* Move session to specific window. */
 462 int
 463 session_select(struct session *s, int idx)
 464 {
 465         struct winlink  *wl;
 466
 467         wl = winlink_find_by_index(&s->windows, idx);
 468         return (session_set_current(s, wl));
 469 }
 470
 471 /* Move session to last used window. */
 472 int
 473 session_last(struct session *s)
 474 {
 475         struct winlink  *wl;
 476
 477         wl = TAILQ_FIRST(&s->lastw);
 478         if (wl == NULL)
 479                 return (-1);
 480         if (wl == s->curw)
 481                 return (1);
 482
 483         return (session_set_current(s, wl));
 484 }
 485
 486 /* Set current winlink to wl .*/
 487 int
 488 session_set_current(struct session *s, struct winlink *wl)
 489 {
 490         struct winlink  *old = s->curw;
 491
 492         if (wl == NULL)
 493                 return (-1);
 494         if (wl == s->curw)
 495                 return (1);
 496
 497         winlink_stack_remove(&s->lastw, wl);
 498         winlink_stack_push(&s->lastw, s->curw);
 499         s->curw = wl;
 500         if (options_get_number(global_options, "focus-events")) {
 501                 if (old != NULL)
 502                         window_update_focus(old->window);
 503                 window_update_focus(wl->window);
 504         }
 505         winlink_clear_flags(wl);
 506         window_update_activity(wl->window);
 507         tty_update_window_offset(wl->window);
 508         notify_session("session-window-changed", s);
 509         return (0);
 510 }
 511
 512 /* Find the session group containing a session. */
 513 struct session_group *
 514 session_group_contains(struct session *target)
 515 {
 516         struct session_group    *sg;
 517         struct session          *s;
 518
 519         RB_FOREACH(sg, session_groups, &session_groups) {
 520                 TAILQ_FOREACH(s, &sg->sessions, gentry) {
 521                         if (s == target)
 522                                 return (sg);
 523                 }
 524         }
 525         return (NULL);
 526 }
 527
 528 /* Find session group by name. */
 529 struct session_group *
 530 session_group_find(const char *name)
 531 {
 532         struct session_group    sg;
 533
 534         sg.name = name;
 535         return (RB_FIND(session_groups, &session_groups, &sg));
 536 }
 537
 538 /* Create a new session group. */
 539 struct session_group *
 540 session_group_new(const char *name)
 541 {
 542         struct session_group    *sg;
 543
 544         if ((sg = session_group_find(name)) != NULL)
 545                 return (sg);
 546
 547         sg = xcalloc(1, sizeof *sg);
 548         sg->name = xstrdup(name);
 549         TAILQ_INIT(&sg->sessions);
 550
 551         RB_INSERT(session_groups, &session_groups, sg);
 552         return (sg);
 553 }
 554
 555 /* Add a session to a session group. */
 556 void
 557 session_group_add(struct session_group *sg, struct session *s)
 558 {
 559         if (session_group_contains(s) == NULL)
 560                 TAILQ_INSERT_TAIL(&sg->sessions, s, gentry);
 561 }
 562
 563 /* Remove a session from its group and destroy the group if empty. */
 564 static void
 565 session_group_remove(struct session *s)
 566 {
 567         struct session_group    *sg;
 568
 569         if ((sg = session_group_contains(s)) == NULL)
 570                 return;
 571         TAILQ_REMOVE(&sg->sessions, s, gentry);
 572         if (TAILQ_EMPTY(&sg->sessions)) {
 573                 RB_REMOVE(session_groups, &session_groups, sg);
 574                 free((void *)sg->name);
 575                 free(sg);
 576         }
 577 }
 578
 579 /* Count number of sessions in session group. */
 580 u_int
 581 session_group_count(struct session_group *sg)
 582 {
 583         struct session  *s;
 584         u_int            n;
 585
 586         n = 0;
 587         TAILQ_FOREACH(s, &sg->sessions, gentry)
 588                 n++;
 589         return (n);
 590 }
 591
 592 /* Count number of clients attached to sessions in session group. */
 593 u_int
 594 session_group_attached_count(struct session_group *sg)
 595 {
 596         struct session  *s;
 597         u_int            n;
 598
 599         n = 0;
 600         TAILQ_FOREACH(s, &sg->sessions, gentry)
 601                 n += s->attached;
 602         return (n);
 603 }
 604
 605 /* Synchronize a session to its session group. */
 606 void
 607 session_group_synchronize_to(struct session *s)
 608 {
 609         struct session_group    *sg;
 610         struct session          *target;
 611
 612         if ((sg = session_group_contains(s)) == NULL)
 613                 return;
 614
 615         target = NULL;
 616         TAILQ_FOREACH(target, &sg->sessions, gentry) {
 617                 if (target != s)
 618                         break;
 619         }
 620         if (target != NULL)
 621                 session_group_synchronize1(target, s);
 622 }
 623
 624 /* Synchronize a session group to a session. */
 625 void
 626 session_group_synchronize_from(struct session *target)
 627 {
 628         struct session_group    *sg;
 629         struct session          *s;
 630
 631         if ((sg = session_group_contains(target)) == NULL)
 632                 return;
 633
 634         TAILQ_FOREACH(s, &sg->sessions, gentry) {
 635                 if (s != target)
 636                         session_group_synchronize1(target, s);
 637         }
 638 }
 639
 640 /*
 641  * Synchronize a session with a target session. This means destroying all
 642  * winlinks then recreating them, then updating the current window, last window
 643  * stack and alerts.
 644  */
 645 static void
 646 session_group_synchronize1(struct session *target, struct session *s)
 647 {
 648         struct winlinks          old_windows, *ww;
 649         struct winlink_stack     old_lastw;
 650         struct winlink          *wl, *wl2;
 651
 652         /* Don't do anything if the session is empty (it'll be destroyed). */
 653         ww = &target->windows;
 654         if (RB_EMPTY(ww))
 655                 return;
 656
 657         /* If the current window has vanished, move to the next now. */
 658         if (s->curw != NULL &&
 659             winlink_find_by_index(ww, s->curw->idx) == NULL &&
 660             session_last(s) != 0 && session_previous(s, 0) != 0)
 661                 session_next(s, 0);
 662
 663         /* Save the old pointer and reset it. */
 664         memcpy(&old_windows, &s->windows, sizeof old_windows);
 665         RB_INIT(&s->windows);
 666
 667         /* Link all the windows from the target. */
 668         RB_FOREACH(wl, winlinks, ww) {
 669                 wl2 = winlink_add(&s->windows, wl->idx);
 670                 wl2->session = s;
 671                 winlink_set_window(wl2, wl->window);
 672                 notify_session_window("window-linked", s, wl2->window);
 673                 wl2->flags |= wl->flags & WINLINK_ALERTFLAGS;
 674         }
 675
 676         /* Fix up the current window. */
 677         if (s->curw != NULL)
 678                 s->curw = winlink_find_by_index(&s->windows, s->curw->idx);
 679         else
 680                 s->curw = winlink_find_by_index(&s->windows, target->curw->idx);
 681
 682         /* Fix up the last window stack. */
 683         memcpy(&old_lastw, &s->lastw, sizeof old_lastw);
 684         TAILQ_INIT(&s->lastw);
 685         TAILQ_FOREACH(wl, &old_lastw, sentry) {
 686                 wl2 = winlink_find_by_index(&s->windows, wl->idx);
 687                 if (wl2 != NULL) {
 688                         TAILQ_INSERT_TAIL(&s->lastw, wl2, sentry);
 689                         wl2->flags |= WINLINK_VISITED;
 690                 }
 691         }
 692
 693         /* Then free the old winlinks list. */
 694         while (!RB_EMPTY(&old_windows)) {
 695                 wl = RB_ROOT(&old_windows);
 696                 wl2 = winlink_find_by_window_id(&s->windows, wl->window->id);
 697                 if (wl2 == NULL)
 698                         notify_session_window("window-unlinked", s, wl->window);
 699                 winlink_remove(&old_windows, wl);
 700         }
 701 }
 702
 703 /* Renumber the windows across winlinks attached to a specific session. */
 704 void
 705 session_renumber_windows(struct session *s)
 706 {
 707         struct winlink          *wl, *wl1, *wl_new;
 708         struct winlinks          old_wins;
 709         struct winlink_stack     old_lastw;
 710         int                      new_idx, new_curw_idx, marked_idx = -1;
 711
 712         /* Save and replace old window list. */
 713         memcpy(&old_wins, &s->windows, sizeof old_wins);
 714         RB_INIT(&s->windows);
 715
 716         /* Start renumbering from the base-index if it's set. */
 717         new_idx = options_get_number(s->options, "base-index");
 718         new_curw_idx = 0;
 719
 720         /* Go through the winlinks and assign new indexes. */
 721         RB_FOREACH(wl, winlinks, &old_wins) {
 722                 wl_new = winlink_add(&s->windows, new_idx);
 723                 wl_new->session = s;
 724                 winlink_set_window(wl_new, wl->window);
 725                 wl_new->flags |= wl->flags & WINLINK_ALERTFLAGS;
 726
 727                 if (wl == marked_pane.wl)
 728                         marked_idx = wl_new->idx;
 729                 if (wl == s->curw)
 730                         new_curw_idx = wl_new->idx;
 731
 732                 new_idx++;
 733         }
 734
 735         /* Fix the stack of last windows now. */
 736         memcpy(&old_lastw, &s->lastw, sizeof old_lastw);
 737         TAILQ_INIT(&s->lastw);
 738         TAILQ_FOREACH(wl, &old_lastw, sentry) {
 739                 wl->flags &= ~WINLINK_VISITED;
 740                 wl_new = winlink_find_by_window(&s->windows, wl->window);
 741                 if (wl_new != NULL) {
 742                         TAILQ_INSERT_TAIL(&s->lastw, wl_new, sentry);
 743                         wl_new->flags |= WINLINK_VISITED;
 744                 }
 745         }
 746
 747         /* Set the current window. */
 748         if (marked_idx != -1) {
 749                 marked_pane.wl = winlink_find_by_index(&s->windows, marked_idx);
 750                 if (marked_pane.wl == NULL)
 751                         server_clear_marked();
 752         }
 753         s->curw = winlink_find_by_index(&s->windows, new_curw_idx);
 754
 755         /* Free the old winlinks (reducing window references too). */
 756         RB_FOREACH_SAFE(wl, winlinks, &old_wins, wl1)
 757                 winlink_remove(&old_wins, wl);
 758 }