/* $OpenBSD: server-fn.c,v 1.148 2026/07/14 19:07:03 nicm Exp $ */

/*

 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER

 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING

 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include <sys/types.h>

#include <sys/wait.h>

#include <sys/uio.h>

#include <signal.h>

#include <stdlib.h>

#include <string.h>

#include <time.h>

#include <unistd.h>

#include "tmux.h"

static void server_destroy_session_group(struct session *);

static void server_fire_pane_exit(const char *, struct window_pane *);

static void

server_fire_pane_exit(const char *name, struct window_pane *wp)

{

  struct event_payload  *ep;

  struct cmd_find_state  fs;

  int      status = wp->status;

  const char    *signame;

  if (WIFSIGNALED(status))

    signame = sig2name(WTERMSIG(status));

  ep = event_payload_create();

  cmd_find_from_pane(&fs, wp, 0);

  event_payload_set_target(ep, &fs);

  event_payload_set_pane(ep, "pane", wp);

  event_payload_set_window(ep, "window", wp->window);

  if (WIFEXITED(status))

    event_payload_set_int(ep, "exit_status", WEXITSTATUS(status));

  else if (WIFSIGNALED(status))

    event_payload_set_string(ep, "exit_signal", "%s", signame);

  event_payload_set_int(ep, "exit_success", status == 0);

  events_fire(name, ep);

}

void

server_redraw_client(struct client *c)

{

  c->flags |= CLIENT_ALLREDRAWFLAGS;

}

void

server_status_client(struct client *c)

{

  c->flags |= CLIENT_REDRAWSTATUS;

}

void

server_redraw_session(struct session *s)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session == s)

      server_redraw_client(c);

  }

}

void

server_redraw_session_group(struct session *s)

{

  struct session_group  *sg;

  if ((sg = session_group_contains(s)) == NULL)

    server_redraw_session(s);

  else {

    TAILQ_FOREACH(s, &sg->sessions, gentry)

      server_redraw_session(s);

  }

}

void

server_status_session(struct session *s)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session == s)

      server_status_client(c);

  }

}

void

server_status_session_group(struct session *s)

{

  struct session_group  *sg;

  if ((sg = session_group_contains(s)) == NULL)

    server_status_session(s);

  else {

    TAILQ_FOREACH(s, &sg->sessions, gentry)

      server_status_session(s);

  }

}

void

server_redraw_window(struct window *w)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session != NULL &&

        c->session->curw != NULL &&

        c->session->curw->window == w)

      server_redraw_client(c);

  }

}

void

server_redraw_window_menu(struct window *w)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session != NULL &&

        c->session->curw != NULL &&

        c->session->curw->window == w)

      c->flags |= CLIENT_REDRAWMENU;

  }

}

void

server_redraw_window_borders(struct window *w)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session != NULL &&

        c->session->curw != NULL &&

        c->session->curw->window == w)

      c->flags |= CLIENT_REDRAWBORDERS;

  }

}

void

server_status_window(struct window *w)

{

  struct session  *s;

  /*

   * This is slightly different. We want to redraw the status line of any

   * clients containing this window rather than anywhere it is the

   * current window.

   */

  RB_FOREACH(s, sessions, &sessions) {

    if (session_has(s, w))

      server_status_session(s);

  }

}

void

server_lock(void)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session != NULL)

      server_lock_client(c);

  }

}

void

server_lock_session(struct session *s)

{

  struct client *c;

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session == s)

      server_lock_client(c);

  }

}

void

server_lock_client(struct client *c)

{

  const char  *cmd;

  if (c->flags & CLIENT_CONTROL)

    return;

  if (c->flags & CLIENT_SUSPENDED)

    return;

  cmd = options_get_string(c->session->options, "lock-command");

  if (*cmd == '\0' || strlen(cmd) + 1 > MAX_IMSGSIZE - IMSG_HEADER_SIZE)

    return;

  tty_stop_tty(&c->tty);

  tty_raw(&c->tty, tty_term_string(c->tty.term, TTYC_SMCUP));

  tty_raw(&c->tty, tty_term_string(c->tty.term, TTYC_CLEAR));

  tty_raw(&c->tty, tty_term_string(c->tty.term, TTYC_E3));

  c->flags |= CLIENT_SUSPENDED;

  proc_send(c->peer, MSG_LOCK, -1, cmd, strlen(cmd) + 1);

}

void

server_kill_pane(struct window_pane *wp)

{

  struct window *w = wp->window;

  if (window_count_panes(w, 1) == 1) {

    server_kill_window(w, 1);

    recalculate_sizes();

  } else {

    server_unzoom_window(w);

    server_client_remove_pane(wp);

    layout_close_pane(wp);

    window_remove_pane(w, wp);

    server_redraw_window(w);

  }

}

void

server_kill_window(struct window *w, int renumber)

{

  struct session  *s, *s1;

  struct winlink  *wl;

  window_add_ref(w, __func__);

  RB_FOREACH_SAFE(s, sessions, &sessions, s1) {

    if (!session_has(s, w))

      continue;

    server_unzoom_window(w);

    while ((wl = winlink_find_by_window(&s->windows, w)) != NULL) {

      if (session_detach(s, wl)) {

        server_destroy_session_group(s);

        break;

      }

      server_redraw_session_group(s);

    }

    if (renumber)

      server_renumber_session(s);

  }

  recalculate_sizes();

  window_remove_ref(w, __func__);

}

void

server_renumber_session(struct session *s)

{

  struct session_group  *sg;

  if (options_get_number(s->options, "renumber-windows")) {

    if ((sg = session_group_contains(s)) != NULL) {

      TAILQ_FOREACH(s, &sg->sessions, gentry)

          session_renumber_windows(s);

    } else

      session_renumber_windows(s);

  }

}

void

server_renumber_all(void)

{

  struct session  *s;

  RB_FOREACH(s, sessions, &sessions)

    server_renumber_session(s);

}

int

server_link_window(struct session *src, struct winlink *srcwl,

    struct session *dst, int dstidx, int killflag, int selectflag,

    char **cause)

{

  struct winlink    *dstwl;

  struct session_group  *srcsg, *dstsg;

  srcsg = session_group_contains(src);

  dstsg = session_group_contains(dst);

  if (src != dst && srcsg != NULL && dstsg != NULL && srcsg == dstsg) {

    xasprintf(cause, "sessions are grouped");

    return (-1);

  }

  dstwl = NULL;

  if (dstidx != -1)

    dstwl = winlink_find_by_index(&dst->windows, dstidx);

  if (dstwl != NULL) {

    if (dstwl->window == srcwl->window) {

      xasprintf(cause, "same index: %d", dstidx);

      return (-1);

    }

    if (killflag) {

      /*

       * Can't use session_detach as it will destroy session

       * if this makes it empty.

       */

      events_fire_winlink("window-unlinked", dstwl);

      dstwl->flags &= ~WINLINK_ALERTFLAGS;

      winlink_stack_remove(&dst->lastw, dstwl);

      winlink_remove(&dst->windows, dstwl);

      /* Force select/redraw if current. */

      if (dstwl == dst->curw) {

        selectflag = 1;

        dst->curw = NULL;

      }

    }

  }

  if (dstidx == -1)

    dstidx = -1 - options_get_number(dst->options, "base-index");

  dstwl = session_attach(dst, srcwl->window, dstidx, cause);

  if (dstwl == NULL)

    return (-1);

  if (marked_pane.wl == srcwl)

    marked_pane.wl = dstwl;

  if (selectflag)

    session_select(dst, dstwl->idx);

  server_redraw_session_group(dst);

  return (0);

}

void

server_unlink_window(struct session *s, struct winlink *wl)

{

  if (session_detach(s, wl))

    server_destroy_session_group(s);

  else

    server_redraw_session_group(s);

}

void

server_destroy_pane(struct window_pane *wp, int notify)

{

  struct window   *w = wp->window;

  struct screen_write_ctx  ctx;

  struct grid_cell   gc;

  int      remain_on_exit;

  const char    *s;

  char      *expanded;

  u_int      sx = screen_size_x(&wp->base);

  u_int      sy = screen_size_y(&wp->base);

  if (wp->fd != -1) {

#ifdef HAVE_UTEMPTER

    utempter_remove_record(wp->fd);

    kill(getpid(), SIGCHLD);

#endif

    bufferevent_free(wp->event);

    wp->event = NULL;

    close(wp->fd);

    wp->fd = -1;

  }

  remain_on_exit = options_get_number(wp->options, "remain-on-exit");

  if (remain_on_exit != 0 && (~wp->flags & PANE_STATUSREADY))

    return;

  switch (remain_on_exit) {

  case 0:

    break;

  case 2:

    if (WIFEXITED(wp->status) && WEXITSTATUS(wp->status) == 0)

      break;

    /* FALLTHROUGH */

  case 1:

  case 3:

    if (wp->flags & PANE_STATUSDRAWN)

      return;

    wp->flags |= PANE_STATUSDRAWN;

    gettimeofday(&wp->dead_time, NULL);

    if (notify)

      server_fire_pane_exit("pane-died", wp);

    s = options_get_string(wp->options, "remain-on-exit-format");

    if (*s != '\0') {

      screen_write_start_pane(&ctx, wp, &wp->base);

      screen_write_scrollregion(&ctx, 0, sy - 1);

      screen_write_cursormove(&ctx, 0, sy - 1, 0);

      screen_write_linefeed(&ctx, 1, 8);

      memcpy(&gc, &grid_default_cell, sizeof gc);

      expanded = format_single(NULL, s, NULL, NULL, NULL, wp);

      format_draw(&ctx, &gc, sx, expanded, NULL, 0);

      free(expanded);

      screen_write_stop(&ctx);

    }

    wp->base.mode &= ~MODE_CURSOR;

    wp->flags |= PANE_REDRAW;

    return;

  }

  if (notify)

    server_fire_pane_exit("pane-exited", wp);

  server_unzoom_window(w);

  server_client_remove_pane(wp);

  layout_close_pane(wp);

  window_remove_pane(w, wp);

  if (TAILQ_EMPTY(&w->panes))

    server_kill_window(w, 1);

  else

    server_redraw_window(w);

}

static void

server_destroy_session_group(struct session *s)

{

  struct session_group  *sg;

  struct session    *s1;

  if ((sg = session_group_contains(s)) == NULL) {

    server_destroy_session(s);

    session_destroy(s, 1, __func__);

  } else {

    TAILQ_FOREACH_SAFE(s, &sg->sessions, gentry, s1) {

      server_destroy_session(s);

      session_destroy(s, 1, __func__);

    }

  }

}

static struct session *

server_find_session(struct session *s,

    int (*f)(struct session *, struct session *))

{

  struct session *s_loop, *s_out = NULL;

  RB_FOREACH(s_loop, sessions, &sessions) {

    if (s_loop != s && f(s_loop, s_out))

      s_out = s_loop;

  }

  return (s_out);

}

static int

server_newer_session(struct session *s_loop, struct session *s_out)

{

  if (s_out == NULL)

    return (1);

  return (timercmp(&s_loop->activity_time, &s_out->activity_time, >));

}

static int

server_newer_detached_session(struct session *s_loop, struct session *s_out)

{

  if (s_loop->attached)

    return (0);

  return (server_newer_session(s_loop, s_out));

}

void

server_destroy_session(struct session *s)

{

  struct client *c;

  struct session  *s_new = NULL, *cs_new = NULL, *use_s;

  struct sort_criteria   sort_crit = { .order = SORT_NAME };

  int    detach_on_destroy;

  detach_on_destroy = options_get_number(s->options, "detach-on-destroy");

  if (detach_on_destroy == 0)

    s_new = server_find_session(s, server_newer_session);

  else if (detach_on_destroy == 2)

    s_new = server_find_session(s, server_newer_detached_session);

  else if (detach_on_destroy == 3)

    s_new = session_previous_session(s, &sort_crit);

  else if (detach_on_destroy == 4)

    s_new = session_next_session(s, &sort_crit);

  if (s_new == s)

    s_new = NULL;

  /*

   * If no suitable new session was found above, then look for any

   * session as an alternative in case a client needs it.

   */

  if (s_new == NULL &&

      (detach_on_destroy == 1 || detach_on_destroy == 2))

    cs_new = server_find_session(s, server_newer_session);

  TAILQ_FOREACH(c, &clients, entry) {

    if (c->session != s)

      continue;

    use_s = s_new;

    if (use_s == NULL && (c->flags & CLIENT_NO_DETACH_ON_DESTROY))

      use_s = cs_new;

    c->session = NULL;

    c->last_session = NULL;

    server_client_set_session(c, use_s);

    if (use_s == NULL)

      c->flags |= CLIENT_EXIT;

  }

  recalculate_sizes();

}

void

server_check_unattached(void)

{

  struct session    *s;

  struct session_group  *sg;

  /*

   * If any sessions are no longer attached and have destroy-unattached

   * set, collect them.

   */

  RB_FOREACH(s, sessions, &sessions) {

    if (s->attached != 0)

      continue;

    switch (options_get_number(s->options, "destroy-unattached")) {

    case 0: /* off */

      continue;

    case 1: /* on */

      break;

    case 2: /* keep-last */

      sg = session_group_contains(s);

      if (sg == NULL || session_group_count(sg) <= 1)

        continue;

      break;

    case 3: /* keep-group */

      sg = session_group_contains(s);

      if (sg != NULL && session_group_count(sg) == 1)

        continue;

      break;

    }

    session_destroy(s, 1, __func__);

  }

}

void

server_unzoom_window(struct window *w)

{

  if (window_unzoom(w, 1) == 0)

    server_redraw_window(w);

}