/src/tmux/server-client.c

Source
/* $OpenBSD: server-client.c,v 1.530 2026/10/27 13:00:14 nicm Exp $ */

/*
 * Copyright (c) 2009 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/ioctl.h>
#include <sys/uio.h>

#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "tmux.h"

static void server_client_free(int, short, void *);
static void server_client_check_pane_resize(struct window_pane *);
static void server_client_check_pane_buffer(struct window_pane *);
static void server_client_check_window_resize(struct window *);
static key_code server_client_check_mouse(struct client *, struct key_event *);
static void server_client_repeat_timer(int, short, void *);
static void server_client_click_timer(int, short, void *);
static void server_client_check_exit(struct client *, int);
static void server_client_exit_timer(int, short, void *);
static void server_client_check_redraw(struct client *);
static void server_client_check_modes(struct client *);
static void server_client_set_title(struct client *);
static void server_client_set_path(struct client *);
static void server_client_set_progress_bar(struct client *);
static void server_client_reset_state(struct client *);
static void server_client_update_latest(struct client *);
static int  server_client_handle_dead_key(struct window_pane *, key_code);
static int  server_client_handle_key0(struct client *, struct key_event *,
        struct cmdq_item *, struct cmdq_item **, int);
static enum cmd_retval  server_client_key_callback(struct cmdq_item *, void *);
static void server_client_dispatch(struct imsg *, void *);
static int  server_client_dispatch_command(struct client *, struct imsg *);
static int  server_client_dispatch_identify(struct client *, struct imsg *);
static int  server_client_dispatch_shell(struct client *);
static void server_client_report_theme(struct client *, enum client_theme);

/* Clients that have been lost but not yet freed. */
struct clients dead_clients = TAILQ_HEAD_INITIALIZER(dead_clients);

/* Number of attached clients. */
u_int
server_client_how_many(void)
{
  struct client *c;
  u_int    n;

  n = 0;
  TAILQ_FOREACH(c, &clients, entry) {
    if (c->session != NULL && (~c->flags & CLIENT_UNATTACHEDFLAGS))
      n++;
  }
  return (n);
}

/* Are these ranges empty? That is, nothing is visible. */
int
server_client_ranges_is_empty(struct visible_ranges *r)
{
  u_int i;

  for (i = 0; i < r->used; i++) {
    if (r->ranges[i].nx != 0)
      return (0);
  }
  return (1);
}

/* Ensure we have space for at least n ranges. */
void
server_client_ensure_ranges(struct visible_ranges *r, u_int n)
{
  if (r->size >= n)
    return;
  r->ranges = xrecallocarray(r->ranges, r->size, n, sizeof *r->ranges);
  r->size = n;
}

/* Check if this client is inside this server. */
int
server_client_check_nested(struct client *c)
{
  struct environ_entry  *envent;
  struct window_pane  *wp;

  envent = environ_find(c->environ, "TMUX");
  if (envent == NULL || *envent->value == '\0')
    return (0);

  RB_FOREACH(wp, window_pane_tree, &all_window_panes) {
    if (strcmp(wp->tty, c->ttyname) == 0)
      return (1);
  }
  return (0);
}

/* Set client key table. */
void
server_client_set_key_table(struct client *c, const char *name)
{
  if (name == NULL)
    name = server_client_get_key_table(c);

  key_bindings_unref_table(c->keytable);
  c->keytable = key_bindings_get_table(name, 1);
  c->keytable->references++;
  if (gettimeofday(&c->keytable->activity_time, NULL) != 0)
    fatal("gettimeofday failed");
}

static uint64_t
server_client_key_table_activity_diff(struct client *c)
{
  struct timeval  diff;

  timersub(&c->activity_time, &c->keytable->activity_time, &diff);
  return ((diff.tv_sec * 1000ULL) + (diff.tv_usec / 1000ULL));
}

/* Get default key table. */
const char *
server_client_get_key_table(struct client *c)
{
  struct session  *s = c->session;
  const char  *name;

  if (s == NULL)
    return ("root");

  name = options_get_string(s->options, "key-table");
  if (*name == '\0')
    return ("root");
  return (name);
}

/* Is this table the default key table? */
static int
server_client_is_default_key_table(struct client *c, struct key_table *table)
{
  return (strcmp(table->name, server_client_get_key_table(c)) == 0);
}

/* Create a new client. */
struct client *
server_client_create(int fd)
{
  struct client *c;
  u_int    i;

  setblocking(fd, 0);

  c = xcalloc(1, sizeof *c);
  c->references = 1;
  c->peer = proc_add_peer(server_proc, fd, server_client_dispatch, c);

  if (gettimeofday(&c->creation_time, NULL) != 0)
    fatal("gettimeofday failed");
  memcpy(&c->activity_time, &c->creation_time, sizeof c->activity_time);

  c->environ = environ_create();

  c->fd = -1;
  c->out_fd = -1;

  c->queue = cmdq_new();
  RB_INIT(&c->files);

  c->tty.sx = 80;
  c->tty.sy = 24;

  for (i = 0; i < COLOUR_THEME_COUNT; i++)
    c->theme_colours[i] = 8;
  c->theme = THEME_UNKNOWN;

  status_init(c);
  status_side_init(c);
  c->flags |= CLIENT_FOCUSED;

  c->keytable = key_bindings_get_table("root", 1);
  c->keytable->references++;

  evtimer_set(&c->repeat_timer, server_client_repeat_timer, c);
  evtimer_set(&c->click_timer, server_client_click_timer, c);
  evtimer_set(&c->exit_timer, server_client_exit_timer, c);

  c->click_wp = -1;

  TAILQ_INIT(&c->input_requests);

  TAILQ_INSERT_TAIL(&clients, c, entry);
  log_debug("new client %p", c);
  return (c);
}

/* Open client terminal if needed. */
int
server_client_open(struct client *c, char **cause)
{
  const char  *ttynam = _PATH_TTY;

  if (c->flags & CLIENT_CONTROL)
    return (0);

  if (strcmp(c->ttyname, ttynam) == 0||
      ((isatty(STDIN_FILENO) &&
      (ttynam = ttyname(STDIN_FILENO)) != NULL &&
      strcmp(c->ttyname, ttynam) == 0) ||
      (isatty(STDOUT_FILENO) &&
      (ttynam = ttyname(STDOUT_FILENO)) != NULL &&
      strcmp(c->ttyname, ttynam) == 0) ||
      (isatty(STDERR_FILENO) &&
      (ttynam = ttyname(STDERR_FILENO)) != NULL &&
      strcmp(c->ttyname, ttynam) == 0))) {
    xasprintf(cause, "can't use %s", c->ttyname);
    return (-1);
  }

  if (!(c->flags & CLIENT_TERMINAL)) {
    *cause = xstrdup("not a terminal");
    return (-1);
  }

  if (tty_open(&c->tty, cause) != 0)
    return (-1);

  server_client_update_theme_colours(c);
  return (0);
}

/* Lost an attached client. */
static void
server_client_attached_lost(struct client *c)
{
  struct session  *s;
  struct window *w;
  struct client *loop;
  struct client *found;

  log_debug("lost attached client %p", c);

  /*
   * By this point the session in the client has been cleared so walk all
   * windows to find any with this client as the latest.
   */
  RB_FOREACH(w, windows, &windows) {
    if (w->latest != c)
      continue;

    found = NULL;
    TAILQ_FOREACH(loop, &clients, entry) {
      s = loop->session;
      if (loop == c || s == NULL || s->curw->window != w)
        continue;
      if (found == NULL || timercmp(&loop->activity_time,
          &found->activity_time, >))
        found = loop;
    }
    if (found != NULL)
      server_client_update_latest(found);
  }
}

/* Fire client session changed. */
static void
server_client_fire_session_changed(struct client *c, struct session *old)
{
  struct event_payload  *ep;
  struct cmd_find_state  fs;

  ep = event_payload_create();
  cmd_find_from_client(&fs, c, 0);
  event_payload_set_target(ep, &fs);
  event_payload_set_client(ep, "client", c);
  if (fs.s != NULL) {
    event_payload_set_session(ep, "session", fs.s);
    event_payload_set_session(ep, "new_session", fs.s);
  }
  if (old != NULL)
    event_payload_set_session(ep, "old_session", old);
  if (fs.w != NULL)
    event_payload_set_window(ep, "window", fs.w);
  if (fs.wl != NULL)
    event_payload_set_int(ep, "window_index", fs.wl->idx);
  else if (fs.idx != -1)
    event_payload_set_int(ep, "window_index", fs.idx);
  if (fs.wp != NULL)
    event_payload_set_pane(ep, "pane", fs.wp);
  events_fire("client-session-changed", ep);
}

/* Fire client resized. */
static void
server_client_fire_resized(struct client *c, u_int old_sx, u_int old_sy)
{
  struct event_payload  *ep;
  struct cmd_find_state  fs;

  ep = event_payload_create();
  cmd_find_from_client(&fs, c, 0);
  event_payload_set_target(ep, &fs);
  event_payload_set_client(ep, "client", c);
  if (fs.s != NULL)
    event_payload_set_session(ep, "session", fs.s);
  if (fs.w != NULL)
    event_payload_set_window(ep, "window", fs.w);
  if (fs.wl != NULL)
    event_payload_set_int(ep, "window_index", fs.wl->idx);
  else if (fs.idx != -1)
    event_payload_set_int(ep, "window_index", fs.idx);
  if (fs.wp != NULL)
    event_payload_set_pane(ep, "pane", fs.wp);
  event_payload_set_uint(ep, "width", c->tty.sx);
  event_payload_set_uint(ep, "height", c->tty.sy);
  event_payload_set_uint(ep, "old_width", old_sx);
  event_payload_set_uint(ep, "old_height", old_sy);
  events_fire("client-resized", ep);
}

/* Recalculate sizes and notify a resized client. */
static void
server_client_apply_resize(struct client *c, u_int old_sx, u_int old_sy)
{
  if (c->session != NULL) {
    recalculate_sizes();
    server_redraw_client(c);
    server_client_fire_resized(c, old_sx, old_sy);
  }
}

/* Apply a new reported size. */
void
server_client_size_changed(struct client *c, u_int sx, u_int sy)
{
  u_int old_sx = c->tty.sx, old_sy = c->tty.sy;

  if (c->flags & CLIENT_CONTROL)
    return;
  if (sx == 0 || sy == 0 || (sx == old_sx && sy == old_sy))
    return;

  log_debug("%s: reported size %ux%u (was %ux%u)", c->name, sx, sy,
      old_sx, old_sy);
  server_client_update_latest(c);
  tty_set_size(&c->tty, sx, sy, c->tty.xpixel, c->tty.ypixel);
  tty_invalidate(&c->tty);
  server_client_apply_resize(c, old_sx, old_sy);
}

/* Set client session. */
void
server_client_set_session(struct client *c, struct session *s)
{
  struct session  *old = c->session;

  if (s != NULL && c->session != NULL && c->session != s)
    c->last_session = c->session;
  else if (s == NULL)
    c->last_session = NULL;
  c->session = s;
  c->flags |= CLIENT_FOCUSED;

  if (old != NULL && old->curw != NULL)
    window_update_focus(old->curw->window);
  if (s != NULL) {
    s->curw->window->latest = c;
    recalculate_sizes();
    window_update_focus(s->curw->window);
    session_update_activity(s, NULL);
    session_theme_changed(s);
    gettimeofday(&s->last_attached_time, NULL);
    s->curw->flags &= ~WINLINK_ALERTFLAGS;
    alerts_check_session(s);
    tty_update_client_offset(c);
    status_timer_start(c);
    server_client_fire_session_changed(c, old);

    /*
     * Redraw if the session or displayed window changed. Use the
     * cached scene because the session's current window is already set.
     */
    if (old != s || !redraw_client_has_window(c, s->curw->window))
      server_redraw_client(c);
  }

  server_check_unattached();
  server_update_socket();
}

/* Lost a client. */
void
server_client_lost(struct client *c)
{
  struct client_file  *cf, *cf1;

  cfg_client_lost(c);
  c->flags |= CLIENT_DEAD;

  status_prompt_clear(c);
  status_message_clear(c);

  RB_FOREACH_SAFE(cf, client_files, &c->files, cf1) {
    cf->error = EINTR;
    file_fire_done(cf);
  }

  TAILQ_REMOVE(&clients, c, entry);
  TAILQ_INSERT_TAIL(&dead_clients, c, entry);
  log_debug("lost client %p", c);

  cmd_wait_for_client_lost(c);
  cmdq_next(c);

  if (c->flags & CLIENT_ATTACHED) {
    server_client_attached_lost(c);
    events_fire_client("client-detached", c);
  }
  if (c->name != NULL && (c->flags & (CLIENT_CONTROL|CLIENT_TERMINAL)))
    events_fire_client("client-closed", c);

  c->session = NULL;
  c->last_session = NULL;

  if (c->flags & CLIENT_CONTROL)
    control_stop(c);
  if (c->flags & CLIENT_TERMINAL)
    tty_free(&c->tty);
  free(c->ttyname);
  free(c->clipboard_panes);

  free(c->term_name);
  free(c->term_type);
  tty_term_free_list(c->term_caps, c->term_ncaps);

  status_free(c);
  status_side_free(c);
  input_cancel_requests(c);

  free(c->title);
  free(c->path);
  free((void *)c->cwd);
  free(c->exit_session);
  free(c->exit_message);

  evtimer_del(&c->repeat_timer);
  evtimer_del(&c->click_timer);
  evtimer_del(&c->exit_timer);
  if (event_initialized(&c->cycle_timer))
    evtimer_del(&c->cycle_timer);

  key_bindings_unref_table(c->keytable);

  free(c->message_string);
  if (event_initialized(&c->message_timer))
    evtimer_del(&c->message_timer);
  prompt_free(c->prompt);

  format_lost_client(c);
  environ_free(c->environ);

  proc_remove_peer(c->peer);
  c->peer = NULL;

  if (c->out_fd != -1)
    close(c->out_fd);
  if (c->fd != -1) {
    close(c->fd);
    c->fd = -1;
  }
  server_client_unref(c);

  server_add_accept(0); /* may be more file descriptors now */

  recalculate_sizes();
  server_check_unattached();
  server_update_socket();
}

/* Remove reference from a client. */
void
server_client_unref(struct client *c)
{
  log_debug("unref client %p (%d references)", c, c->references);

  c->references--;
  if (c->references == 0)
    event_once(-1, EV_TIMEOUT, server_client_free, c, NULL);
}

/* Free dead client. */
static void
server_client_free(__unused int fd, __unused short events, void *arg)
{
  struct client *c = arg;

  log_debug("free client %p (%d references)", c, c->references);

  TAILQ_REMOVE(&dead_clients, c, entry);
  redraw_free_scene(c->redraw_scene);
  cmdq_free(c->queue);

  if (c->references == 0) {
    free((void *)c->name);
    free((void *)c->user);
    free(c);
  }
}

/* Suspend a client. */
void
server_client_suspend(struct client *c)
{
  struct session  *s = c->session;

  if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
    return;

  tty_stop_tty(&c->tty);
  c->flags |= CLIENT_SUSPENDED;
  proc_send(c->peer, MSG_SUSPEND, -1, NULL, 0);
}

/* Detach a client. */
void
server_client_detach(struct client *c, enum msgtype msgtype)
{
  struct session  *s = c->session;

  if (s == NULL || (c->flags & CLIENT_NODETACHFLAGS))
    return;

  c->flags |= CLIENT_EXIT;

  c->exit_type = CLIENT_EXIT_DETACH;
  c->exit_msgtype = msgtype;
  c->exit_session = xstrdup(s->name);
}

/* Execute command to replace a client. */
void
server_client_exec(struct client *c, const char *cmd)
{
  struct session  *s = c->session;
  char    *msg;
  const char  *shell;
  size_t     cmdsize, shellsize;

  if (*cmd == '\0')
    return;
  cmdsize = strlen(cmd) + 1;

  if (s != NULL)
    shell = options_get_string(s->options, "default-shell");
  else
    shell = options_get_string(global_s_options, "default-shell");
  if (!checkshell(shell))
    shell = _PATH_BSHELL;
  shellsize = strlen(shell) + 1;

  msg = xmalloc(cmdsize + shellsize);
  memcpy(msg, cmd, cmdsize);
  memcpy(msg + cmdsize, shell, shellsize);

  proc_send(c->peer, MSG_EXEC, -1, msg, cmdsize + shellsize);
  free(msg);
}

/* Is this point inside the auto-hide scrollbar interaction area? */
static int
server_client_in_scrollbar_area(struct window_pane *wp, int px, int py)
{
  struct window *w = wp->window;
  u_int    width, pad, total;
  int    start, end;

  if (!window_pane_scrollbar_overlay(wp))
    return (0);
  if (py < wp->yoff || py >= wp->yoff + (int)wp->sy)
    return (0);

  width = wp->scrollbar_style.width;
  pad = wp->scrollbar_style.pad;
  total = width + pad;
  if (total == 0 || total > wp->sx)
    total = wp->sx;

  if (w->sb_pos == PANE_SCROLLBARS_LEFT) {
    start = wp->xoff;
    end = wp->xoff + (int)total - 1;
  } else {
    end = wp->xoff + (int)wp->sx - 1;
    start = end - (int)total + 1;
  }
  return (px >= start && px <= end);
}

/* Update auto-hide scrollbars for a mouse movement. */
static void
server_client_update_scrollbar_hover(struct client *c, int type, int px, int py)
{
  struct window   *w = c->session->curw->window;
  struct window_pane  *wp;

  if (type != KEYC_TYPE_MOUSEMOVE)
    return;

  TAILQ_FOREACH(wp, &w->panes, entry) {
    if (!window_pane_is_visible(wp))
      continue;
    if (server_client_in_scrollbar_area(wp, px, py)) {
      wp->sb_auto_hover = 1;
      window_pane_scrollbar_show(wp, 1);
    } else {
      wp->sb_auto_hover = 0;
      window_pane_scrollbar_start_timer(wp);
    }
  }
}

/* Is the mouse inside a pane? */
static enum key_code_mouse_location
server_client_check_mouse_in_pane(struct window_pane *wp, int px, int py,
    u_int *sl_mpos)
{
  struct window   *w = wp->window;
  struct window_pane  *fwp;
  int      pane_status, sb_w, sb_pad;
  int      pane_status_line, sl_top, sl_bottom;
  int      bdr_bottom, bdr_top, bdr_left, bdr_right;
  int      sb_start, sb_end, sb_overlay;

  pane_status = window_pane_get_pane_status(wp);
  sb_overlay = window_pane_scrollbar_overlay(wp);

  if (window_pane_scrollbar_visible(wp)) {
    sb_w = wp->scrollbar_style.width;
    sb_pad = wp->scrollbar_style.pad;
    if (sb_overlay && sb_w > (int)wp->sx)
      sb_w = wp->sx;
  } else {
    sb_w = 0;
    sb_pad = 0;
  }

  if (pane_status == PANE_STATUS_TOP)
    pane_status_line = wp->yoff - 1;
  else if (pane_status == PANE_STATUS_BOTTOM)
    pane_status_line = wp->yoff + wp->sy;
  else
    pane_status_line = -1; /* not used */
  bdr_left = wp->xoff - 1;
  if (!sb_overlay && w->sb_pos == PANE_SCROLLBARS_LEFT)
    bdr_left -= sb_pad + sb_w;

  if (sb_overlay && sb_w != 0 &&
      py >= wp->yoff && py < wp->yoff + (int)wp->sy &&
      px >= wp->xoff && px < wp->xoff + (int)wp->sx) {
    if (w->sb_pos == PANE_SCROLLBARS_LEFT) {
      sb_start = wp->xoff;
      sb_end = sb_start + sb_w - 1;
    } else {
      sb_end = wp->xoff + (int)wp->sx - 1;
      sb_start = sb_end - sb_w + 1;
    }
    if (px >= sb_start && px <= sb_end) {
      sl_top = wp->yoff + wp->sb_slider_y;
      sl_bottom = (wp->yoff + wp->sb_slider_y +
          wp->sb_slider_h - 1);
      if (py < sl_top)
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_UP);
      else if (py >= sl_top && py <= sl_bottom) {
        *sl_mpos = (py - wp->sb_slider_y - wp->yoff);
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_SLIDER);
      } else
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_DOWN);
    }
    return (KEYC_MOUSE_LOCATION_PANE);
  }

  /* Check if point is within the pane or scrollbar. */
  if (((pane_status != PANE_STATUS_OFF &&
      py != pane_status_line && py != wp->yoff + (int)wp->sy) ||
      (wp->yoff == 0 && py < (int)wp->sy) ||
      (py >= wp->yoff && py < wp->yoff + (int)wp->sy)) &&
      ((w->sb_pos == PANE_SCROLLBARS_RIGHT &&
      px < wp->xoff + (int)wp->sx + sb_pad + sb_w) ||
      (w->sb_pos == PANE_SCROLLBARS_LEFT &&
      px < wp->xoff + (int)wp->sx - sb_pad - sb_w))) {
    /* Check if in the scrollbar. */
    if ((w->sb_pos == PANE_SCROLLBARS_RIGHT &&
        (px >= wp->xoff + (int)wp->sx + sb_pad &&
        px < wp->xoff + (int)wp->sx + sb_pad + sb_w)) ||
        (w->sb_pos == PANE_SCROLLBARS_LEFT &&
        (px >= wp->xoff - sb_pad - sb_w &&
        px < wp->xoff - sb_pad))) {
      /* Check where inside the scrollbar. */
      sl_top = wp->yoff + wp->sb_slider_y;
      sl_bottom = (wp->yoff + wp->sb_slider_y +
          wp->sb_slider_h - 1);
      if (py < sl_top)
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_UP);
      else if (py >= sl_top && py <= sl_bottom) {
        *sl_mpos = (py - wp->sb_slider_y - wp->yoff);
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_SLIDER);
      } else /* py > sl_bottom */
        return (KEYC_MOUSE_LOCATION_SCROLLBAR_DOWN);
    } else if (window_pane_is_floating(wp) &&
        window_pane_get_pane_lines(wp) != PANE_LINES_NONE &&
        (px == bdr_left ||
        py == wp->yoff - 1 ||
        py == wp->yoff + (int)wp->sy)) {
      /* Floating pane left, bottom or top border. */
      return (KEYC_MOUSE_LOCATION_BORDER);
    } else {
      /* Must be inside the pane. */
      return (KEYC_MOUSE_LOCATION_PANE);
    }
  } else {
    /* Try the pane borders. */
    TAILQ_FOREACH(fwp, &w->panes, entry) {
      if (!window_pane_is_visible(fwp))
        continue;
      if (window_pane_is_floating(fwp) &&
          window_pane_get_pane_lines(fwp) == PANE_LINES_NONE)
        continue;
      if (window_pane_scrollbar_reserve(fwp)) {
        sb_w = fwp->scrollbar_style.width;
        sb_pad = fwp->scrollbar_style.pad;
      } else {
        sb_w = 0;
        sb_pad = 0;
      }
      bdr_top = fwp->yoff - 1;
      bdr_bottom = fwp->yoff + fwp->sy;
      bdr_left = fwp->xoff - 1;
      if (w->sb_pos == PANE_SCROLLBARS_LEFT) {
        bdr_left -= sb_pad + sb_w;
        bdr_right = fwp->xoff + fwp->sx;
      } else {
        /* PANE_SCROLLBARS_RIGHT or none. */
        bdr_right = fwp->xoff + fwp->sx + sb_pad + sb_w;
      }
      if (py >= fwp->yoff - 1 &&
          py <= fwp->yoff + (int)fwp->sy) {
        if (px == bdr_right)
          break;
        if (window_pane_is_floating(wp)) {
          /* Floating pane, check left border. */
          if (px == bdr_left)
            break;
        }
      }
      if (px >= bdr_left && px <= fwp->xoff + (int)fwp->sx) {
        bdr_bottom = fwp->yoff + fwp->sy;
        if (py == bdr_bottom)
          break;
        if (py == bdr_top)
          break;
      }
    }
    if (fwp != NULL)
      return (KEYC_MOUSE_LOCATION_BORDER);
  }
  return (KEYC_MOUSE_LOCATION_NOWHERE);
}

/* Check for mouse events on the status lines. */
static int
server_client_check_mouse_status(struct client *c, struct mouse_event *m,
    enum key_code_type type, u_int x, u_int y,
    enum key_code_mouse_location *loc)
{
  struct tty      *tty = &c->tty;
  struct winlink      *fwl;
  struct window_pane    *fwp;
  struct session      *s = c->session, *fs;
  struct style_range    *sr;
  u_int        n, sidey, separator;
  int        side = 0, mflag = tty->mouse_drag_flag;
  enum key_code_mouse_location   mloc = tty->mouse_drag_location;

  *loc = KEYC_MOUSE_LOCATION_NOWHERE;

  m->statusat = status_at_line(c);
  m->statuslines = status_line_size(c);
  m->sideat = status_side_at_column(c);
  m->sidewidth = status_side_size(c);

  if (mflag != 0 && mloc == KEYC_MOUSE_LOCATION_SIDE_STATUS_BORDER) {
    *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_BORDER;
    return (0);
  }

  if (m->statusat != -1 &&
      y >= (u_int)m->statusat &&
      y < m->statusat + m->statuslines) {
    sr = status_get_range(c, x, y - m->statusat);
  } else {
    if (m->sideat == -1 ||
        x < (u_int)m->sideat ||
        x >= m->sideat + m->sidewidth) {
      goto not_on_status;
    }
    if (m->statusat == 0)
      sidey = m->statuslines;
    else
      sidey = 0;
    if (y < sidey || y - sidey >= status_side_rows(c))
      goto not_on_status;
    separator = m->sideat;
    if (separator == 0)
      separator = m->sidewidth - 1;
    if (m->sidewidth > 1 && x == separator) {
      *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_BORDER;
      if (type == KEYC_TYPE_MOUSEDRAG && mflag == 0)
        tty->mouse_drag_status = 1;
      return (0);
    }
    side = 1;
    sr = status_side_get_range(c, x - m->sideat, y - sidey);
  }
  if (type == KEYC_TYPE_MOUSEDRAG && mflag == 0)
    tty->mouse_drag_status = 1;
  if (sr == NULL) {
    if (side)
      *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_DEFAULT;
    else
      *loc = KEYC_MOUSE_LOCATION_STATUS_DEFAULT;
    return (0);
  }

  if (side)
    *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS;
  else
    *loc = KEYC_MOUSE_LOCATION_STATUS;
  switch (sr->type) {
  case STYLE_RANGE_NONE:
    return (-1);
  case STYLE_RANGE_LEFT:
    log_debug("mouse range: left");
    if (side)
      *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_LEFT;
    else
      *loc = KEYC_MOUSE_LOCATION_STATUS_LEFT;
    break;
  case STYLE_RANGE_RIGHT:
    log_debug("mouse range: right");
    if (side)
      *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_RIGHT;
    else
      *loc = KEYC_MOUSE_LOCATION_STATUS_RIGHT;
    break;
  case STYLE_RANGE_PANE:
    fwp = window_pane_find_by_id(sr->argument);
    if (fwp == NULL)
      return (-1);
    m->wp = sr->argument;

    log_debug("mouse range: pane %%%u", m->wp);
    break;
  case STYLE_RANGE_WINDOW:
    fwl = winlink_find_by_index(&s->windows, sr->argument);
    if (fwl == NULL)
      return (-1);
    m->w = fwl->window->id;

    log_debug("mouse range: window @%u", m->w);
    break;
  case STYLE_RANGE_SESSION:
    fs = session_find_by_id(sr->argument);
    if (fs == NULL)
      return (-1);
    m->s = sr->argument;

    log_debug("mouse range: session $%u", m->s);
    break;
  case STYLE_RANGE_USER:
    log_debug("mouse range: user");
    break;
  case STYLE_RANGE_CONTROL:
    n = sr->argument; /* parsing keeps this < 10 */
    log_debug("mouse range: control %u", n);
    if (side)
      *loc = KEYC_MOUSE_LOCATION_SIDE_STATUS_CONTROL0 + n;
    else
      *loc = KEYC_MOUSE_LOCATION_CONTROL0 + n;
    break;
  }
  return (0);

not_on_status:
  /* Keep drags started on status lines from triggering pane bindings. */
  if (type == KEYC_TYPE_MOUSEDRAG && tty->mouse_drag_status)
    *loc = mloc;
  return (0);
}

/* Check for mouse keys. */
static key_code
server_client_check_mouse(struct client *c, struct key_event *event)
{
  struct mouse_event    *m = &event->m;
  struct session      *s = c->session;
  struct window     *w = s->curw->window;
  struct window_pane    *wp, *lwp = NULL;
  u_int        x, y, sx, sy, px, py, n, sl_mpos = 0;
  u_int        b, bn;
  int        ignore = 0;
  int        modal_drag = 0;
  key_code       key;
  struct timeval       tv;
  struct style_range    *sr;
  enum key_code_type     type = KEYC_TYPE_NOTYPE;
  enum key_code_mouse_location   loc = KEYC_MOUSE_LOCATION_NOWHERE;

  log_debug("%s mouse %02x at %u,%u (last %u,%u) (%d)", c->name, m->b,
      m->x, m->y, m->lx, m->ly, c->tty.mouse_drag_flag);

  /* Find last pane, if any. */
  if (c->tty.mouse_last_pane != -1) {
    lwp = window_pane_find_by_id(c->tty.mouse_last_pane);
    if (lwp != NULL)
      log_debug("%s mouse last pane %%%u", c->name, lwp->id);
  }

  /* What type of event is this? */
  if (event->key == KEYC_DOUBLECLICK) {
    type = KEYC_TYPE_DOUBLECLICK;
    x = m->x, y = m->y, b = m->b;
    ignore = 1;
    log_debug("double-click at %u,%u", x, y);
  } else if ((m->sgr_type != ' ' &&
      MOUSE_DRAG(m->sgr_b) &&
      MOUSE_RELEASE(m->sgr_b)) ||
      (m->sgr_type == ' ' &&
      MOUSE_DRAG(m->b) &&
      MOUSE_RELEASE(m->b) &&
      MOUSE_RELEASE(m->lb))) {
    type = KEYC_TYPE_MOUSEMOVE;
    x = m->x, y = m->y, b = 0;
    log_debug("move at %u,%u", x, y);
  } else if (MOUSE_DRAG(m->b)) {
    type = KEYC_TYPE_MOUSEDRAG;
    if (c->tty.mouse_drag_flag) {
      x = m->x, y = m->y, b = m->b;
      if (x == m->lx && y == m->ly)
        return (KEYC_UNKNOWN);
      log_debug("drag update at %u,%u", x, y);
    } else {
      x = m->lx, y = m->ly, b = m->lb;
      c->tty.mouse_drag_status = 0;
      log_debug("drag start at %u,%u", x, y);
    }
  } else if (MOUSE_WHEEL(m->b)) {
    if ((m->b & MOUSE_MASK_BUTTONS) == MOUSE_WHEEL_UP)
      type = KEYC_TYPE_WHEELUP;
    else
      type = KEYC_TYPE_WHEELDOWN;
    x = m->x, y = m->y, b = m->b;
    log_debug("wheel at %u,%u", x, y);
  } else if (MOUSE_RELEASE(m->b)) {
    type = KEYC_TYPE_MOUSEUP;
    x = m->x, y = m->y, b = m->lb;
    if (m->sgr_type == 'm')
      b = m->sgr_b;
    log_debug("up at %u,%u", x, y);
  } else {
    if (c->flags & CLIENT_DOUBLECLICK) {
      evtimer_del(&c->click_timer);
      c->flags &= ~CLIENT_DOUBLECLICK;
      type = KEYC_TYPE_SECONDCLICK;
      x = m->x, y = m->y, b = m->b;
      log_debug("second-click at %u,%u", x, y);
      c->flags |= CLIENT_TRIPLECLICK;
    } else if (c->flags & CLIENT_TRIPLECLICK) {
      evtimer_del(&c->click_timer);
      c->flags &= ~CLIENT_TRIPLECLICK;
      type = KEYC_TYPE_TRIPLECLICK;
      x = m->x, y = m->y, b = m->b;
      log_debug("triple-click at %u,%u", x, y);
      goto have_event;
    }

    /* DOWN is the only remaining event type. */
    if (type == KEYC_TYPE_NOTYPE) {
      type = KEYC_TYPE_MOUSEDOWN;
      x = m->x, y = m->y, b = m->b;
      log_debug("down at %u,%u", x, y);
      c->flags |= CLIENT_DOUBLECLICK;
    }
  }

have_event:
  if (type == KEYC_TYPE_NOTYPE)
    return (KEYC_UNKNOWN);

  /* Save the session. */
  m->s = s->id;
  m->w = -1;
  m->wp = -1;
  m->ignore = ignore;

  if (server_client_check_mouse_status(c, m, type, x, y, &loc) != 0)
    return (KEYC_UNKNOWN);
  if (w->modal != NULL && loc != KEYC_MOUSE_LOCATION_NOWHERE)
    return (KEYC_UNKNOWN);

  /*
   * Not on status line. Adjust position and check for border, pane, or
   * scrollbar.
   */
  if (loc == KEYC_MOUSE_LOCATION_NOWHERE && c->tty.mouse_scrolling_flag) {
    if (lwp != NULL) {
      loc = KEYC_MOUSE_LOCATION_SCROLLBAR_SLIDER;
      m->wp = lwp->id;
      m->w = lwp->window->id;
    }
  } else if (loc == KEYC_MOUSE_LOCATION_NOWHERE) {
    if (m->sideat == 0 && x >= m->sidewidth)
      px = x - m->sidewidth;
    else if (m->sideat > 0 && x >= (u_int)m->sideat)
      px = m->sideat - 1;
    else
      px = x;
    if (m->statusat == 0 && y >= m->statuslines)
      py = y - m->statuslines;
    else if (m->statusat > 0 && y >= (u_int)m->statusat)
      py = m->statusat - 1;
    else
      py = y;

    tty_window_offset(&c->tty, &m->ox, &m->oy, &sx, &sy);
    log_debug("mouse window @%u at %u,%u (%ux%u)", w->id, m->ox,
        m->oy, sx, sy);
    if (px > sx || py > sy) {
      server_client_update_scrollbar_hover(c, type, -1, -1);
      return (KEYC_UNKNOWN);
    }
    px = px + m->ox;
    py = py + m->oy;
    if (w->modal != NULL &&
        !window_pane_contains(w->modal, px, py)) {
      if (lwp == w->modal &&
          c->tty.mouse_drag_flag != 0 &&
          (type == KEYC_TYPE_MOUSEDRAG ||
          type == KEYC_TYPE_MOUSEUP)) {
        modal_drag = 1;
        wp = lwp;
        loc = KEYC_MOUSE_LOCATION_PANE;
        m->wp = wp->id;
        m->w = wp->window->id;
      } else {
        server_client_update_scrollbar_hover(c, type,
            -1, -1);
        c->tty.mouse_drag_update = NULL;
        c->tty.mouse_drag_release = NULL;
        c->tty.mouse_drag_flag = 0;
        c->tty.mouse_scrolling_flag = 0;
        c->tty.mouse_slider_mpos = -1;
        c->tty.mouse_last_pane = -1;
        if ((w->modal->flags & PANE_CLOSEONCLICK) &&
            (type == KEYC_TYPE_MOUSEDOWN ||
            type == KEYC_TYPE_SECONDCLICK ||
            type == KEYC_TYPE_TRIPLECLICK))
          server_kill_pane(w->modal);
        return (KEYC_UNKNOWN);
      }
    }
    server_client_update_scrollbar_hover(c, type, px, py);

    if (modal_drag) {
      /* Keep the drag with the modal pane. */
    } else if (type == KEYC_TYPE_MOUSEDRAG && lwp != NULL) {
      /* Use pane from last mouse event. */
      wp = lwp;
    } else {
      /* Try inside the pane. */
      wp = window_get_active_at(w, px, py);
    }
    if (wp == NULL) {
      loc = KEYC_MOUSE_LOCATION_EMPTY;
      m->w = w->id;
      log_debug("mouse %u,%u on empty area", x, y);
    } else {
      if (!modal_drag) {
        loc = server_client_check_mouse_in_pane(wp, px,
            py, &sl_mpos);
      }
      if (loc == KEYC_MOUSE_LOCATION_PANE) {
        log_debug("mouse %u,%u on pane %%%u", x, y,
            wp->id);
      } else if (loc == KEYC_MOUSE_LOCATION_BORDER) {
        sr = window_pane_status_get_range(wp, px, py);
        if (sr != NULL) {
          n = sr->argument;
          loc = KEYC_MOUSE_LOCATION_CONTROL0 + n;
        }
        log_debug("mouse on pane %%%u border", wp->id);
      } else if (loc == KEYC_MOUSE_LOCATION_SCROLLBAR_UP ||
          loc == KEYC_MOUSE_LOCATION_SCROLLBAR_SLIDER ||
          loc == KEYC_MOUSE_LOCATION_SCROLLBAR_DOWN) {
        log_debug("mouse on pane %%%u scrollbar",
            wp->id);
      }
      m->wp = wp->id;
      m->w = wp->window->id;
    }
  } else
    server_client_update_scrollbar_hover(c, type, -1, -1);

  /* Reset click type or add a click timer if needed. */
  if (type == KEYC_TYPE_MOUSEDOWN ||
      type == KEYC_TYPE_SECONDCLICK ||
      type == KEYC_TYPE_TRIPLECLICK) {
    if (type != KEYC_TYPE_MOUSEDOWN &&
        (m->b != c->click_button ||
        loc != (enum key_code_mouse_location)c->click_loc ||
        m->wp != c->click_wp)) {
      type = KEYC_TYPE_MOUSEDOWN;
      log_debug("click sequence reset at %u,%u", x, y);
      c->flags &= ~CLIENT_TRIPLECLICK;
      c->flags |= CLIENT_DOUBLECLICK;
    }

    if (type != KEYC_TYPE_TRIPLECLICK && KEYC_CLICK_TIMEOUT != 0) {
      memcpy(&c->click_event, m, sizeof c->click_event);
      c->click_button = m->b;
      c->click_loc = loc;
      c->click_wp = m->wp;

      log_debug("click timer started");
      tv.tv_sec = KEYC_CLICK_TIMEOUT / 1000;
      tv.tv_usec = (KEYC_CLICK_TIMEOUT % 1000) * 1000L;
      evtimer_add(&c->click_timer, &tv);
    }
  }

  key = KEYC_UNKNOWN;

  /* Stop dragging if needed. */
  if (type != KEYC_TYPE_MOUSEDRAG &&
      type != KEYC_TYPE_WHEELUP &&
      type != KEYC_TYPE_WHEELDOWN &&
      type != KEYC_TYPE_DOUBLECLICK &&
      type != KEYC_TYPE_TRIPLECLICK &&
      c->tty.mouse_drag_flag != 0) {
    if (c->tty.mouse_drag_release != NULL)
      c->tty.mouse_drag_release(c, m);

    c->tty.mouse_drag_update = NULL;
    c->tty.mouse_drag_release = NULL;
    c->tty.mouse_scrolling_flag = 0;

    /*
     * End a mouse drag by passing a MouseDragEnd key corresponding
     * to the button that started the drag.
     */
    type = KEYC_TYPE_MOUSEDRAGEND;
    c->tty.mouse_drag_flag = 0;
    c->tty.mouse_slider_mpos = -1;
    c->tty.mouse_last_pane = -1;
  }

  /* Convert to a key binding. */
  if (type == KEYC_TYPE_MOUSEMOVE && loc == KEYC_MOUSE_LOCATION_PANE) {
    key = KEYC_MOUSEMOVE_PANE;
    if (wp != NULL &&
        wp != w->active &&
        options_get_number(s->options, "focus-follows-mouse")) {
      window_redraw_active_switch(w, wp);
      window_set_active_pane(w, wp, 1);
      server_redraw_window_borders(w);
      server_status_window(w);
    }
  }
  if (type == KEYC_TYPE_MOUSEDRAG) {
    if (c->tty.mouse_drag_update != NULL)
      key = KEYC_DRAGGING;

    /*
     * Begin a drag by setting the flag to a non-zero value that
     * corresponds to the mouse button in use. If starting to drag
     * the scrollbar, store the relative position in the slider
     * where the user grabbed.
     */
    if (c->tty.mouse_drag_flag == 0) {
      c->tty.mouse_drag_location = loc;
      if (c->tty.mouse_drag_status) {
        c->tty.mouse_drag_x = x;
        c->tty.mouse_drag_y = y;
      } else {
        c->tty.mouse_drag_x = px;
        c->tty.mouse_drag_y = py;
      }
    }
    c->tty.mouse_drag_flag = MOUSE_BUTTONS(b) + 1;

    /* Change the pane if the drag did not start on status line. */
    if (!c->tty.mouse_drag_status && lwp == NULL) {
      lwp = wp = window_get_active_at(w, px, py);
      if (wp != NULL)
        c->tty.mouse_last_pane = wp->id;
    }

    /* Change scrollbar position if needed. */
    if (c->tty.mouse_scrolling_flag == 0 &&
        loc == KEYC_MOUSE_LOCATION_SCROLLBAR_SLIDER) {
      c->tty.mouse_scrolling_flag = 1;
      if (m->statusat == 0) {
        c->tty.mouse_slider_mpos = sl_mpos +
            m->statuslines;
      } else
        c->tty.mouse_slider_mpos = sl_mpos;
    }
  }

  if (key == KEYC_UNKNOWN) {
    /* Adjust the button number. */
    if (type == KEYC_TYPE_MOUSEMOVE)
      bn = 0;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_1)
      bn = 1;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_2)
      bn = 2;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_3)
      bn = 3;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_6)
      bn = 6;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_7)
      bn = 7;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_8)
      bn = 8;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_9)
      bn = 9;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_10)
      bn = 10;
    else if (MOUSE_BUTTONS(b) == MOUSE_BUTTON_11)
      bn = 11;
    else
      bn = 0;
    key = KEYC_MAKE_MOUSE_KEY(type, bn, loc);
  }

  /* Apply modifiers if any. */
  if (b & MOUSE_MASK_META)
    key |= KEYC_META;
  if (b & MOUSE_MASK_CTRL)
    key |= KEYC_CTRL;
  if (b & MOUSE_MASK_SHIFT)
    key |= KEYC_SHIFT;

  if (log_get_level() != 0)
    log_debug("mouse key is %s", key_string_lookup_key (key, 1));
  return (key);
}

/* Update client theme colours from server options. */
void
server_client_update_theme_colours(struct client *c)
{
  struct format_tree  *ft;
  const char    *name, *value;
  enum client_theme  theme;
  char      *expanded;
  u_int      i;
  int      colour, option;

  if (c == NULL)
    return;

  option = options_get_number(global_options, "theme");
  if (option == 1) {
    for (i = 0; i < COLOUR_THEME_COUNT; i++)
      c->theme_colours[i] = colour_theme_terminal_colour(i);
    return;
  }

  ft = format_create(c, NULL, FORMAT_NONE, FORMAT_NOJOBS);
  format_defaults(ft, c, NULL, NULL, NULL);

  theme = c->theme;
  if (theme == THEME_UNKNOWN)
    theme = colour_totheme(c->tty.bg);
  if (option == 2)
    theme = THEME_LIGHT;
  else if (option == 3)
    theme = THEME_DARK;
  for (i = 0; i < COLOUR_THEME_COUNT; i++) {
    c->theme_colours[i] = 8;
    name = colour_theme_option(i, theme);
    if (name == NULL)
      continue;
    value = options_get_string(global_options, name);
    expanded = format_expand(ft, value);
    colour = colour_fromstring(expanded);
    free(expanded);
    if (colour == -1 || (colour & COLOUR_FLAG_THEME))
      continue;
    c->theme_colours[i] = colour;
  }

  format_free(ft);
}

/* Is this a bracket paste key? */
static int
server_client_is_bracket_paste(struct client *c, key_code key)
{
  if ((key & KEYC_MASK_KEY) == KEYC_PASTE_START) {
    c->flags |= CLIENT_BRACKETPASTING;
    c->paste_time = current_time;
    log_debug("%s: bracket paste on", c->name);
    return (0);
  }

  if ((key & KEYC_MASK_KEY) == KEYC_PASTE_END) {
    c->flags &= ~CLIENT_BRACKETPASTING;
    log_debug("%s: bracket paste off", c->name);
    return (0);
  }

  return !!(c->flags & CLIENT_BRACKETPASTING);
}

/* Is this fast enough to probably be a paste? */
static int
server_client_is_assume_paste(struct client *c)
{
  struct session  *s = c->session;
  struct timeval   tv;
  int    t;

  if (c->flags & CLIENT_BRACKETPASTING)
    return (0);
  if ((t = options_get_number(s->options, "assume-paste-time")) == 0)
    return (0);
  if (tty_term_has(c->tty.term, TTYC_ENBP))
    return (0);

  timersub(&c->activity_time, &c->last_activity_time, &tv);
  if (tv.tv_sec == 0 && tv.tv_usec < t * 1000) {
    if (c->flags & CLIENT_ASSUMEPASTING)
      return (1);
    c->flags |= CLIENT_ASSUMEPASTING;
    c->paste_time = current_time;
    log_debug("%s: assume paste on", c->name);
    return (0);
  }
  if (c->flags & CLIENT_ASSUMEPASTING) {
    c->flags &= ~CLIENT_ASSUMEPASTING;
    log_debug("%s: assume paste off", c->name);
  }
  return (0);
}

/* Has the latest client changed? */
static void
server_client_update_latest(struct client *c)
{
  struct window *w;

  if (c->session == NULL)
    return;
  w = c->session->curw->window;

  if (w->latest == c)
    return;
  w->latest = c;

  if (options_get_number(w->options, "window-size") == WINDOW_SIZE_LATEST)
    recalculate_size(w, 0);

  events_fire_client("client-active", c);
}

/* Get repeat time. */
static u_int
server_client_repeat_time(struct client *c, struct key_binding *bd)
{
  struct session  *s = c->session;
  u_int    repeat, initial;

  if (~bd->flags & KEY_BINDING_REPEAT)
    return (0);
  repeat = options_get_number(s->options, "repeat-time");
  if (repeat == 0)
    return (0);
  if ((~c->flags & CLIENT_REPEAT) || bd->key != c->last_key) {
    initial = options_get_number(s->options, "initial-repeat-time");
    if (initial != 0)
      repeat = initial;
  }
  return (repeat);
}

/* Handle a key press which closes a dead pane. */
static int
server_client_handle_dead_key(struct window_pane *wp, key_code key)
{
  int remain_on_exit;

  if (wp == NULL ||
      (~wp->flags & PANE_EXITED) ||
      KEYC_IS_MOUSE(key) ||
      KEYC_IS_PASTE(key))
    return (0);
  remain_on_exit = options_get_number(wp->options, "remain-on-exit");
  if (remain_on_exit != 3 && remain_on_exit != 4)
    return (0);
  options_set_number(wp->options, "remain-on-exit", 0);
  server_destroy_pane(wp, 0);
  return (1);
}

/*
 * Handle data key input from client. This owns and can modify the key event it
 * is given and is responsible for freeing it.
 */
static enum cmd_retval
server_client_key_callback(struct cmdq_item *item, void *data)
{
  struct key_event    *event = data;
  struct client     *c, *ec = event->client;
  key_code       key = event->key;
  struct mouse_event    *m = &event->m;
  struct session      *s;
  struct winlink      *wl;
  struct window_pane    *wp;
  struct window_mode_entry  *wme;
  struct timeval       tv;
  struct key_table    *table, *first;
  struct key_binding    *bd;
  u_int        repeat;
  uint64_t       flags, prefix_delay;
  struct cmd_find_state    fs;
  key_code       key0, prefix, prefix2;

  if (ec != NULL)
    c = ec;
  else
    c = cmdq_get_client(item);
  s = c->session;

  /* Check the client is good to accept input. */
  if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
    goto out;

  /* Recheck input handlers opened by earlier queued commands. */
  if (server_client_handle_key0(c, event, NULL, NULL, 1) == 0)
    goto out;

  wl = s->curw;

  /* Update the activity timer. */
  memcpy(&c->last_activity_time, &c->activity_time,
      sizeof c->last_activity_time);
  if (gettimeofday(&c->activity_time, NULL) != 0)
    fatal("gettimeofday failed");
  session_update_activity(s, &c->activity_time);

  /* Check for mouse keys. */
  m->valid = 0;
  if (key == KEYC_MOUSE || key == KEYC_DOUBLECLICK) {
    if (c->flags & CLIENT_READONLY)
      goto out;
    key = server_client_check_mouse(c, event);
    if (key == KEYC_UNKNOWN)
      goto out;

    m->valid = 1;
    m->key = key;

    /*
     * Synchronize direct drag output with the later damage redraw
     * before invoking the drag callback.
     */
    if ((key & KEYC_MASK_KEY) == KEYC_DRAGGING) {
      tty_sync_start(&c->tty);
      c->tty.mouse_drag_update(c, m);
      goto out;
    }
    event->key = key;
  }

  /* Find affected pane. */
  if (!KEYC_IS_MOUSE(key) || cmd_find_from_mouse(&fs, m, 0) != 0)
    cmd_find_from_client(&fs, c, 0);
  wp = fs.wp;

  /* Forward mouse keys if disabled. */
  if (KEYC_IS_MOUSE(key) && !options_get_number(s->options, "mouse"))
    goto forward_key;

  /* Forward if bracket pasting. */
  if (server_client_is_bracket_paste (c, key))
    goto paste_key;

  /* Treat everything as a regular key when pasting is detected. */
  if (!KEYC_IS_MOUSE(key) &&
      key != KEYC_FOCUS_IN &&
      key != KEYC_FOCUS_OUT &&
      (~key & KEYC_SENT) &&
      server_client_is_assume_paste(c))
    goto paste_key;

  /* Forward keys directly if this pane is capturing all keys. */
  if (wp != NULL &&
      (wp->flags & PANE_CAPTUREALLKEYS) &&
      (~wp->flags & PANE_EXITED) &&
      !KEYC_IS_MOUSE(key) &&
      TAILQ_EMPTY(&wp->modes))
    goto forward_key;

  /* Focus events are not keys and cannot be bound. */
  if (key == KEYC_FOCUS_IN || key == KEYC_FOCUS_OUT)
    goto forward_key;

  /*
   * Work out the current key table. If the pane is in a mode, use
   * the mode table instead of the default key table.
   */
  if (server_client_is_default_key_table(c, c->keytable) &&
      wp != NULL &&
      (wme = TAILQ_FIRST(&wp->modes)) != NULL &&
      wme->mode->key_table != NULL)
    table = key_bindings_get_table(wme->mode->key_table(wme), 1);
  else
    table = c->keytable;
  first = table;

table_changed:
  /*
   * The prefix always takes precedence and forces a switch to the prefix
   * table, unless we are already there.
   */
  prefix = (key_code)options_get_number(s->options, "prefix");
  prefix2 = (key_code)options_get_number(s->options, "prefix2");
  key0 = (key & (KEYC_MASK_KEY|KEYC_MASK_MODIFIERS));
  if ((key0 == (prefix & (KEYC_MASK_KEY|KEYC_MASK_MODIFIERS)) ||
      key0 == (prefix2 & (KEYC_MASK_KEY|KEYC_MASK_MODIFIERS))) &&
      strcmp(table->name, "prefix") != 0) {
    server_client_set_key_table(c, "prefix");
    server_status_client(c);
    goto out;
  }
  flags = c->flags;

try_again:
  /* Log key table. */
  if (wp == NULL)
    log_debug("key table %s (no pane)", table->name);
  else
    log_debug("key table %s (pane %%%u)", table->name, wp->id);
  if (c->flags & CLIENT_REPEAT)
    log_debug("currently repeating");

  bd = key_bindings_get(table, key0);

  /*
   * If prefix-timeout is enabled and we're in the prefix table, see if
   * the timeout has been exceeded. Revert to the root table if so.
   */
  prefix_delay = options_get_number(global_options, "prefix-timeout");
  if (prefix_delay > 0 &&
      strcmp(table->name, "prefix") == 0 &&
      server_client_key_table_activity_diff(c) > prefix_delay) {
    /*
     * If repeating is active and this is a repeating binding,
     * ignore the timeout.
     */
    if (bd != NULL &&
        (c->flags & CLIENT_REPEAT) &&
        (bd->flags & KEY_BINDING_REPEAT)) {
      log_debug("prefix timeout ignored, repeat is active");
    } else {
      log_debug("prefix timeout exceeded");
      server_client_set_key_table(c, NULL);
      first = table = c->keytable;
      server_status_client(c);
      goto table_changed;
    }
  }

  /* Try to see if there is a key binding in the current table. */
  if (bd != NULL) {
    /*
     * Key was matched in this table. If currently repeating but a
     * non-repeating binding was found, stop repeating and try
     * again in the root table.
     */
    if ((c->flags & CLIENT_REPEAT) &&
        (~bd->flags & KEY_BINDING_REPEAT)) {
      log_debug("found in key table %s (not repeating)",
          table->name);
      server_client_set_key_table(c, NULL);
      first = table = c->keytable;
      c->flags &= ~CLIENT_REPEAT;
      server_status_client(c);
      goto table_changed;
    }
    log_debug("found in key table %s", table->name);

    /*
     * Take a reference to this table to make sure the key binding
     * doesn't disappear.
     */
    table->references++;

    /*
     * If this is a repeating key, start the timer. Otherwise reset
     * the client back to the root table.
     */
    repeat = server_client_repeat_time(c, bd);
    if (repeat != 0) {
      c->flags |= CLIENT_REPEAT;
      c->last_key = bd->key;

      tv.tv_sec = repeat / 1000;
      tv.tv_usec = (repeat % 1000) * 1000L;
      evtimer_add(&c->repeat_timer, &tv);
    } else {
      c->flags &= ~CLIENT_REPEAT;
      server_client_set_key_table(c, NULL);
    }
    server_status_client(c);

    /* Execute the key binding. */
    key_bindings_dispatch(bd, item, c, event, &fs);
    key_bindings_unref_table(table);
    goto out;
  }

  /*
   * No match, try the ANY key.
   */
  if (key0 != KEYC_ANY) {
    key0 = KEYC_ANY;
    goto try_again;
  }

  /*
   * Binding movement keys is useless since we only turn them on when the
   * application requests, so don't let them exit the prefix table.
   */
  if (KEYC_IS_TYPE(key, KEYC_TYPE_MOUSEMOVE))
    goto forward_key;

  /*
   * No match in this table. If not in the root table or if repeating
   * switch the client back to the root table and try again.
   */
  log_debug("not found in key table %s", table->name);
  if (!server_client_is_default_key_table(c, table) ||
      (c->flags & CLIENT_REPEAT)) {
    log_debug("trying in root table");
    server_client_set_key_table(c, NULL);
    table = c->keytable;
    if (c->flags & CLIENT_REPEAT)
      first = table;
    c->flags &= ~CLIENT_REPEAT;
    server_status_client(c);
    goto table_changed;
  }

  /*
   * No match in the root table either. If this wasn't the first table
   * tried, don't pass the key to the pane.
   */
  if (first != table && (~flags & CLIENT_REPEAT)) {
    server_client_set_key_table(c, NULL);
    server_status_client(c);
    goto out;
  }

forward_key:
  if (server_client_handle_dead_key(wp, key))
    goto out;
  if (c->flags & CLIENT_READONLY)
    goto out;
  if (wp != NULL)
    window_pane_key(wp, c, s, wl, key, m);
  goto out;

paste_key:
  if (c->flags & CLIENT_READONLY)
    goto out;
  if (event->buf != NULL)
    window_pane_paste(wp, key, event->buf, event->len);
  key = KEYC_NONE;
  goto out;

out:
  if (s != NULL && key != KEYC_FOCUS_OUT)
    server_client_update_latest(c);
  if (ec != NULL)
    server_client_unref(ec);
  free(event->buf);
  free(event);
  return (CMD_RETURN_NORMAL);
}

/* Handle a key event for the active window menu, if any. */
static int
server_client_handle_menu_key(struct client *c, struct key_event *event)
{
  struct window   *w = c->session->curw->window;
  struct key_event   new_event;
  struct mouse_event  *m;
  u_int      ox, oy, sx, sy;

  if (w->menu == NULL)
    return (0);

  memcpy(&new_event, event, sizeof new_event);
  if (KEYC_IS_MOUSE(event->key)) {
    m = &new_event.m;
    m->statusat = status_at_line(c);
    m->statuslines = status_line_size(c);
    m->sideat = status_side_at_column(c);
    m->sidewidth = status_side_size(c);

    tty_window_offset(&c->tty, &ox, &oy, &sx, &sy);
    if (m->sideat == 0 && m->x < m->sidewidth)
      m->x = m->y = UINT_MAX;
    else if (m->sideat > 0 && m->x >= (u_int)m->sideat)
      m->x = m->y = UINT_MAX;
    else {
      if (m->sideat == 0)
        m->x -= m->sidewidth;
      m->x += ox;
      if (m->statusat == 0) {
        if (m->y < m->statuslines)
          m->x = m->y = UINT_MAX;
        else
          m->y = m->y - m->statuslines + oy;
      } else if (m->statusat > 0 &&
          m->y >= (u_int)m->statusat)
        m->x = m->y = UINT_MAX;
      else
        m->y += oy;
    }
  }

  if (menu_key(c, w->menu, &new_event) == 1)
    menu_close(w);
  return (1);
}

/* Handle a key; check skips queueing. Returns 0 if used, 1 otherwise. */
static int
server_client_handle_key0(struct client *c, struct key_event *event,
    struct cmdq_item *after, struct cmdq_item **next, int check)
{
  struct session    *s = c->session;
  struct mouse_event  *m = &event->m;
  struct cmdq_item  *item;
  struct window_pane  *wp;
  key_code     key;
  enum key_event_delivery  d = event->delivered;

  /* A consumed key only needs to be freed by the callback. */
  if (check && d == KEY_EVENT_CONSUMED)
    return (0);

  /* Check the client is good to accept input. */
  if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
    return (0);

  if (event->key == KEYC_REPORT_LIGHT_THEME) {
    server_client_report_theme(c, THEME_LIGHT);
    return (0);
  }
  if (event->key == KEYC_REPORT_DARK_THEME) {
    server_client_report_theme(c, THEME_DARK);
    return (0);
  }

  /*
   * Dead panes waiting for a key, modal cancel keys, panes capturing all
   * keys and the command prompt are special cases. The queue might be
   * blocked so they need to be processed immediately rather than queued.
   */
  if (~c->flags & CLIENT_READONLY) {
    if (c->message_string != NULL) {
      if (c->message_ignore_keys)
        return (0);
      status_message_clear(c);
    }

    wp = s->curw->window->active;
    if (server_client_handle_dead_key(wp, event->key))
      return (0);
    if (wp != NULL &&
        wp == wp->window->modal &&
        (wp->flags & PANE_CLOSEONCANCEL) &&
        (event->key == '\033' || event->key == ('c'|KEYC_CTRL))) {
      server_kill_pane(wp);
      return (0);
    }
    if (wp != NULL &&
        (wp->flags & PANE_CAPTUREALLKEYS) &&
        (~wp->flags & PANE_EXITED) &&
        TAILQ_EMPTY(&wp->modes) &&
        (!KEYC_IS_MOUSE(event->key) || wp->wait_item != NULL)) {
      key = event->key;
      if (KEYC_IS_MOUSE(key)) {
        key = server_client_check_mouse(c, event);
        if (key == KEYC_UNKNOWN ||
            (u_int)m->wp != wp->id)
          return (0);
        m->valid = 1;
        m->key = key;
      }
      window_pane_key(wp, c, s, s->curw, key, m);
      return (0);
    }

    if (server_client_handle_menu_key(c, event))
      return (0);
    if (d == KEY_EVENT_NOT_OFFERED && c->prompt != NULL) {
      switch (status_prompt_key(c, event->key, &event->m)) {
      case PROMPT_KEY_HANDLED:
      case PROMPT_KEY_CLOSE:
        return (0);
      case PROMPT_KEY_NOT_HANDLED:
      case PROMPT_KEY_MOVE:
        break;
      }
    }

    wp = s->curw->window->active;
    if (wp == NULL || !window_pane_has_prompt(wp)) {
      TAILQ_FOREACH(wp, &s->curw->window->panes, entry) {
        if (window_pane_has_prompt(wp) &&
            window_pane_is_visible(wp))
          break;
      }
    }
    if (d == KEY_EVENT_NOT_OFFERED &&
        wp != NULL &&
        window_pane_has_prompt(wp) &&
        window_pane_is_visible(wp)) {
      switch (window_pane_prompt_key(wp, c, event->key,
          &event->m)) {
      case PROMPT_KEY_HANDLED:
      case PROMPT_KEY_CLOSE:
      case PROMPT_KEY_MOVE:
        return (0);
      case PROMPT_KEY_NOT_HANDLED:
        if (KEYC_IS_MOUSE(event->key))
          return (0);
        break;
      }
    }
  }
  if (check)
    return (1);

  /*
   * Queue after earlier commands. Mark injected keys too, so waiting
   * prompts can consume them.
   */
  item = cmdq_get_callback(server_client_key_callback, event);
  cmdq_add_flags(item, CMDQ_KEY);
  if (after != NULL) {
    event->client = c;
    c->references++;
    item = cmdq_insert_after(after, item);
    if (next != NULL)
      *next = item;
    return (1);
  }
  cmdq_append(c, item);
  return (1);
}

/* Offer a queued key once. Returns 0 if used, 1 otherwise. */
int
server_client_key_prompt(struct cmdq_item *item, void *data)
{
  struct key_event  *event = data;
  struct client   *c = event->client;
  int      ret;

  if (event->delivered != KEY_EVENT_NOT_OFFERED) {
    if (event->delivered == KEY_EVENT_CONSUMED)
      return (0);
    return (1);
  }
  if (c == NULL)
    c = cmdq_get_client(item);
  if (c == NULL)
    return (1);
  ret = server_client_handle_key0(c, event, NULL, NULL, 1);
  if (ret == 0)
    event->delivered = KEY_EVENT_CONSUMED;
  else
    event->delivered = KEY_EVENT_NOT_CONSUMED;
  return (ret);
}

/* Handle key and insert at end of queue. */
int
server_client_handle_key(struct client *c, struct key_event *event)
{
  return (server_client_handle_key0(c, event, NULL, NULL, 0));
}

/* Handle key and insert after another item. */
int
server_client_handle_key_after(struct client *c, struct key_event *event,
    struct cmdq_item *after, struct cmdq_item **next)
{
  return (server_client_handle_key0(c, event, after, next, 0));
}

/* Client functions that need to happen every loop. */
void
server_client_loop(void)
{
  struct client     *c;
  struct window     *w;
  struct window_pane    *wp;
  struct window_mode_entry  *wme;

  /* Check for window resize. This is done before redrawing. */
  RB_FOREACH(w, windows, &windows)
    server_client_check_window_resize(w);

  /* Notify modes that pane styles may have changed. */
  RB_FOREACH(w, windows, &windows) {
    TAILQ_FOREACH(wp, &w->panes, entry) {
      if (wp->flags & PANE_STYLECHANGED) {
        wme = TAILQ_FIRST(&wp->modes);
        if (wme != NULL &&
            wme->mode->style_changed != NULL)
          wme->mode->style_changed(wme);
      }
    }
  }

  /* Check clients. */
  TAILQ_FOREACH(c, &clients, entry) {
    server_client_check_exit(c, 0);
    if (c->session != NULL && c->session->curw != NULL) {
      server_client_check_modes(c);
      server_client_check_redraw(c);
      server_client_reset_state(c);
    }
  }

  /*
   * Clear window redraw state after processing all clients. Deferred
   * redraws are preserved in client flags.
   */
  RB_FOREACH(w, windows, &windows) {
    TAILQ_FOREACH(wp, &w->panes, entry) {
      if (wp->fd != -1) {
        server_client_check_pane_resize(wp);
        server_client_check_pane_buffer(wp);
      }
      wp->flags &= ~(PANE_REDRAW|PANE_REDRAWSCROLLBAR|
          PANE_ACTIVITY);
    }
    redraw_free_damage(w);

    check_window_name(w);
  }

  /* Send theme updates. */
  RB_FOREACH(w, windows, &windows) {
    TAILQ_FOREACH(wp, &w->panes, entry)
      window_pane_send_theme_update(wp);
  }
}

/* Check if window needs to be resized. */
static void
server_client_check_window_resize(struct window *w)
{
  struct winlink  *wl;

  if (~w->flags & WINDOW_RESIZE)
    return;

  TAILQ_FOREACH(wl, &w->winlinks, wentry) {
    if (wl->session->attached != 0 && wl->session->curw == wl)
      break;
  }
  if (wl == NULL)
    return;

  log_debug("%s: resizing window @%u", __func__, w->id);
  resize_window(w, w->new_sx, w->new_sy, w->new_xpixel, w->new_ypixel);
}

/* Resize timer event. */
static void
server_client_resize_timer(__unused int fd, __unused short events, void *data)
{
  struct window_pane  *wp = data;

  log_debug("%s: %%%u resize timer expired", __func__, wp->id);
  evtimer_del(&wp->resize_timer);
}

/* Check if pane should be resized. */
static void
server_client_check_pane_resize(struct window_pane *wp)
{
  struct window_pane_resize *r, *first, *last;
  struct timeval       tv = { .tv_usec = 250000 };

  if (TAILQ_EMPTY(&wp->resize_queue))
    return;

  if (!event_initialized(&wp->resize_timer))
    evtimer_set(&wp->resize_timer, server_client_resize_timer, wp);
  if (evtimer_pending(&wp->resize_timer, NULL))
    return;

  log_debug("%s: %%%u needs to be resized", __func__, wp->id);
  TAILQ_FOREACH(r, &wp->resize_queue, entry) {
    log_debug("queued resize: %ux%u -> %ux%u", r->osx, r->osy,
        r->sx, r->sy);
  }

  /*
   * There are three cases that matter:
   *
   * - Only one resize. It can just be applied.
   *
   * - Multiple resizes and the ending size is different from the
   *   starting size. We can discard all resizes except the most recent.
   *
   * - Multiple resizes and the ending size is the same as the starting
   *   size. We must resize at least twice to force the application to
   *   redraw. So apply the first and leave the last on the queue for
   *   next time.
   */
  first = TAILQ_FIRST(&wp->resize_queue);
  last = TAILQ_LAST(&wp->resize_queue, window_pane_resizes);
  if (first == last) {
    /* Only one resize. */
    window_pane_send_resize(wp, first->sx, first->sy);
    TAILQ_REMOVE(&wp->resize_queue, first, entry);
    free(first);
  } else if (last->sx != first->osx || last->sy != first->osy) {
    /* Multiple resizes ending up with a different size. */
    window_pane_send_resize(wp, last->sx, last->sy);
    window_pane_clear_resizes(wp, NULL);
  } else {
    /*
     * Multiple resizes ending up with the same size. There will
     * not be more than one to the same size in succession so we
     * can just use the last-but-one on the list and leave the last
     * for later. We reduce the time until the next check to avoid
     * a long delay between the resizes.
     */
    r = TAILQ_PREV(last, window_pane_resizes, entry);
    window_pane_send_resize(wp, r->sx, r->sy);
    window_pane_clear_resizes(wp, last);
    tv.tv_usec = 10000;
  }
  evtimer_add(&wp->resize_timer, &tv);
}

/* Check pane buffer size. */
static void
server_client_check_pane_buffer(struct window_pane *wp)
{
  struct evbuffer     *evb = wp->event->input;
  size_t         minimum;
  struct client     *c;
  struct window_pane_offset *wpo;
  int        off = 1, flag;
  u_int        attached_clients = 0;
  size_t         new_size;

  /*
   * Work out the minimum used size. This is the most that can be removed
   * from the buffer.
   */
  minimum = wp->offset.used;
  if (wp->pipe_fd != -1 && wp->pipe_offset.used < minimum)
    minimum = wp->pipe_offset.used;
  TAILQ_FOREACH(c, &clients, entry) {
    if (c->session == NULL)
      continue;
    attached_clients++;

    if (~c->flags & CLIENT_CONTROL) {
      off = 0;
      continue;
    }
    wpo = control_pane_offset(c, wp, &flag);
    if (wpo == NULL) {
      if (!flag)
        off = 0;
      continue;
    }
    if (!flag)
      off = 0;

    window_pane_get_new_data(wp, wpo, &new_size);
    log_debug("%s: %s has %zu bytes used and %zu left for %%%u",
        __func__, c->name, wpo->used - wp->base_offset, new_size,
        wp->id);
    if (wpo->used < minimum)
      minimum = wpo->used;
  }
  if (attached_clients == 0)
    off = 0;
  minimum -= wp->base_offset;
  if (minimum == 0)
    goto out;

  /* Drain the buffer. */
  log_debug("%s: %%%u has %zu minimum (of %zu) bytes used", __func__,
      wp->id, minimum, EVBUFFER_LENGTH(evb));
  evbuffer_drain(evb, minimum);

  /*
   * Adjust the base offset. If it would roll over, all the offsets into
   * the buffer need to be adjusted.
   */
  if (wp->base_offset > SIZE_MAX - minimum) {
    log_debug("%s: %%%u base offset has wrapped", __func__, wp->id);
    wp->offset.used -= wp->base_offset;
    if (wp->pipe_fd != -1)
      wp->pipe_offset.used -= wp->base_offset;
    TAILQ_FOREACH(c, &clients, entry) {
      if (c->session == NULL || (~c->flags & CLIENT_CONTROL))
        continue;
      wpo = control_pane_offset(c, wp, &flag);
      if (wpo != NULL && !flag)
        wpo->used -= wp->base_offset;
    }
    wp->base_offset = minimum;
  } else
    wp->base_offset += minimum;

out:
  /*
   * If there is data remaining, and there are no clients able to consume
   * it, do not read any more. This is true when there are attached
   * clients, all of which are control clients which are not able to
   * accept any more data.
   */
  log_debug("%s: pane %%%u is %s", __func__, wp->id, off ? "off" : "on");
  if (off)
    bufferevent_disable(wp->event, EV_READ);
  else
    bufferevent_enable(wp->event, EV_READ);
}

/* Move cursor for pane prompt. */
static int
server_client_prompt_cursor(struct client *c, struct window_pane *wp, int *mode,
    u_int *cx, u_int *cy)
{
  struct tty    *tty = &c->tty;
  struct visible_ranges *r;
  u_int      ox, oy, sx, sy;
  int      px, py;

  if (!window_pane_has_prompt(wp))
    return (0);
  *mode &= ~MODE_CURSOR;

  tty_window_offset(tty, &ox, &oy, &sx, &sy);
  if (status_at_line(c) == 0)
    py = wp->yoff;
  else
    py = wp->yoff + wp->sy - 1;
  px = wp->xoff + wp->prompt_cx;
  if (px < (int)ox || px > (int)(ox + sx) ||
      py < (int)oy || py > (int)(oy + sy))
    return (1);

  *cx = px - ox;
  *cy = py - oy;

  r = window_visible_ranges(wp, *cx, *cy, 1, NULL);
  if (window_position_is_visible(r, *cx)) {
    if (status_at_line(c) == 0)
      *cy += status_line_size(c);
    if (status_side_at_column(c) == 0)
      *cx += status_side_size(c);
    *mode |= MODE_CURSOR;
  }
  return (1);
}

/*
 * Update cursor position and mode settings. The scroll region and attributes
 * are cleared when idle (waiting for an event) as this is the most likely time
 * a user may interrupt tmux, for example with ~^Z in ssh(1). This is a
 * compromise between excessive resets and likelihood of an interrupt.
 *
 * tty_region/tty_reset/tty_update_mode already take care of not resetting
 * things that are already in their default state.
 */
static void
server_client_reset_state(struct client *c)
{
  struct tty    *tty = &c->tty;
  struct window   *w = c->session->curw->window;
  struct window_pane  *wp = w->active, *loop;
  struct screen   *s = NULL;
  struct options    *oo = c->session->options;
  int      mode = 0, cursor, flags, pane_mode = 0;
  u_int      cx = 0, cy = 0, ox, oy, sx, sy, prompt = 0;
  u_int      sb_w;
  struct visible_ranges *r;

  if (c->flags & (CLIENT_CONTROL|CLIENT_SUSPENDED))
    return;

  /* Disable the block flag. */
  flags = (tty->flags & TTY_BLOCK);
  tty->flags &= ~TTY_BLOCK;

  /* Get mode from the menu if any, else from the screen. */
  if (w->menu != NULL) {
    menu_get_cursor(w->menu, &cx, &cy);
    s = menu_screen(w->menu);
  } else if (wp != NULL && c->prompt == NULL)
    s = wp->screen;
  else
    s = c->status.active;
  if (s != NULL)
    mode = s->mode;
  if (log_get_level() != 0) {
    log_debug("%s: client %s mode %s", __func__, c->name,
        screen_mode_to_string(mode));
  }

  /* Reset region and margin. */
  tty_region_off(tty);
  tty_margin_off(tty);

  /* Move cursor to pane cursor and offset. */
  if (c->prompt != NULL) {
    prompt = 1;
    status_prompt_cursor(c, &cx, &cy);
  } else if (wp != NULL) {
    if (w->menu != NULL) {
      tty_window_offset(tty, &ox, &oy, &sx, &sy);
      if (cx < ox || cx >= ox + sx ||
          cy < oy || cy >= oy + sy)
        mode &= ~MODE_CURSOR;
      else {
        cx -= ox;
        cy -= oy;
        if (status_at_line(c) == 0)
          cy += status_line_size(c);
        if (status_side_at_column(c) == 0)
          cx += status_side_size(c);
      }
      prompt = 1;
    } else {
      prompt = server_client_prompt_cursor(c, wp, &mode, &cx,
          &cy);
    }
    if (!prompt) {
      cursor = 0;
      pane_mode = s->mode;

      tty_window_offset(tty, &ox, &oy, &sx, &sy);
      if (wp->xoff + (int)s->cx >= (int)ox &&
          wp->xoff + (int)s->cx <= (int)ox + (int)sx &&
          wp->yoff + (int)s->cy >= (int)oy &&
          wp->yoff + (int)s->cy <= (int)oy + (int)sy) {
        cursor = 1;

        cx = wp->xoff + (int)s->cx - (int)ox;
        cy = wp->yoff + (int)s->cy - (int)oy;

        r = window_visible_ranges(wp, cx, cy, 1, NULL);
        if (!window_position_is_visible(r, cx))
          cursor = 0;

        if (window_pane_scrollbar_overlay_visible(wp)) {
          sb_w = wp->scrollbar_style.width;
          if (sb_w > wp->sx)
            sb_w = wp->sx;
          if (sb_w != 0 &&
              w->sb_pos == PANE_SCROLLBARS_LEFT) {
            if (s->cx < sb_w)
              cursor = 0;
          } else if (sb_w != 0 &&
              s->cx >= wp->sx - sb_w)
            cursor = 0;
        }

        if (status_at_line(c) == 0)
          cy += status_line_size(c);
        if (status_side_at_column(c) == 0)
          cx += status_side_size(c);
      }

      if (!cursor)
        mode &= ~MODE_CURSOR;
    }
  } else if (s == NULL)
    mode &= ~MODE_CURSOR;
  if (~pane_mode & MODE_SYNC) {
    log_debug("%s: cursor to %u,%u", __func__, cx, cy);
    tty_cursor(tty, cx, cy);
  } else {
    mode &= ~CURSOR_MODES;
    mode |= tty->mode & CURSOR_MODES;
    s = NULL;
  }

  /*
   * Set mouse mode if requested. To support dragging, always use button
   * mode. For focus-follows-mouse, we need all-motion mode to receive
   * movement events.
   */
  if (options_get_number(oo, "mouse")) {
    if (w->menu == NULL) {
      mode &= ~ALL_MOUSE_MODES;
      TAILQ_FOREACH(loop, &w->panes, entry) {
        if (loop->screen->mode & MODE_MOUSE_ALL)
          mode |= MODE_MOUSE_ALL;
      }
    }
    if (options_get_number(oo, "focus-follows-mouse") ||
        w->sb == PANE_SCROLLBARS_MODAL ||
        w->sb == PANE_SCROLLBARS_AUTOHIDE)
      mode |= MODE_MOUSE_ALL;
    else if (~mode & MODE_MOUSE_ALL)
      mode |= MODE_MOUSE_BUTTON;
  }

  /* Clear bracketed paste mode if at the prompt. */
  if (prompt)
    mode &= ~MODE_BRACKETPASTE;

  /* Set the terminal mode and reset attributes. */
  tty_update_mode(tty, mode, s);
  tty_reset(tty);

  /* All writing must be done, send a sync end (if it was started). */
  tty_sync_end(tty);
  tty->flags |= flags;
}

/* Repeat time callback. */
static void
server_client_repeat_timer(__unused int fd, __unused short events, void *data)
{
  struct client *c = data;

  if (c->flags & CLIENT_REPEAT) {
    server_client_set_key_table(c, NULL);
    c->flags &= ~CLIENT_REPEAT;
    server_status_client(c);
  }
}

/* Double-click callback. */
static void
server_client_click_timer(__unused int fd, __unused short events, void *data)
{
  struct client   *c = data;
  struct key_event  *event;

  log_debug("click timer expired");

  if (c->flags & CLIENT_TRIPLECLICK) {
    /*
     * Waiting for a third click that hasn't happened, so this must
     * have been a double click.
     */
    event = xcalloc(1, sizeof *event);
    event->key = KEYC_DOUBLECLICK;
    memcpy(&event->m, &c->click_event, sizeof event->m);
    if (!server_client_handle_key(c, event)) {
      free(event->buf);
      free(event);
    }
  }
  c->flags &= ~(CLIENT_DOUBLECLICK|CLIENT_TRIPLECLICK);
}

/* Start client exit timer. */
static void
server_client_start_exit_timer(struct client *c)
{
  struct timeval  tv = { .tv_sec = 10 };

  if (!evtimer_pending(&c->exit_timer, NULL))
    evtimer_add(&c->exit_timer, &tv);
}

/* Exit timer has expired: stop waiting for the client. */
static void
server_client_exit_timer(__unused int fd, __unused short events, void *data)
{
  struct client *c = data;

  if (c->flags & (CLIENT_DEAD|CLIENT_SUSPENDED))
    return;

  if (c->flags & CLIENT_EXITED) {
    log_debug("%s: %s took too long to exit", __func__, c->name);
    server_client_lost(c);
  } else if (c->flags & CLIENT_EXIT) {
    log_debug("%s: %s took too long to flush", __func__, c->name);
    server_client_check_exit(c, 1);
  }
}

/* Check if client should be exited, abandoning buffered output if forced. */
static void
server_client_check_exit(struct client *c, int force)
{
  struct client_file  *cf;
  const char    *name = c->exit_session;
  char      *data;
  size_t       size, msize;

  if (c->flags & (CLIENT_DEAD|CLIENT_EXITED))
    return;
  if (~c->flags & CLIENT_EXIT)
    return;

  if ((c->flags & CLIENT_CONTROL) && c->control_state != NULL) {
    if (force)
      control_discard_all(c);
    else {
      control_discard(c);
      if (!control_all_done(c)) {
        server_client_start_exit_timer(c);
        return;
      }
    }
  }
  if (!force) {
    RB_FOREACH(cf, client_files, &c->files) {
      if (EVBUFFER_LENGTH(cf->buffer) != 0) {
        server_client_start_exit_timer(c);
        return;
      }
    }
  }
  c->flags |= CLIENT_EXITED;

  evtimer_del(&c->exit_timer);
  server_client_start_exit_timer(c);

  switch (c->exit_type) {
  case CLIENT_EXIT_RETURN:
    if (c->exit_message != NULL)
      msize = strlen(c->exit_message) + 1;
    else
      msize = 0;
    size = (sizeof c->retval) + msize;
    data = xmalloc(size);
    memcpy(data, &c->retval, sizeof c->retval);
    if (c->exit_message != NULL)
      memcpy(data + sizeof c->retval, c->exit_message, msize);
    proc_send(c->peer, MSG_EXIT, -1, data, size);
    free(data);
    break;
  case CLIENT_EXIT_SHUTDOWN:
    proc_send(c->peer, MSG_SHUTDOWN, -1, NULL, 0);
    break;
  case CLIENT_EXIT_DETACH:
    proc_send(c->peer, c->exit_msgtype, -1, name, strlen(name) + 1);
    break;
  }
}

/* Redraw timer callback. */
static void
server_client_redraw_timer(__unused int fd, __unused short events,
    __unused void *data)
{
  log_debug("redraw timer fired");
}

/*
 * Check if modes need to be updated. Only modes in the current window are
 * updated and it is done when the status line is redrawn.
 */
static void
server_client_check_modes(struct client *c)
{
  struct window     *w = c->session->curw->window;
  struct window_pane    *wp;
  struct window_mode_entry  *wme;

  if (c->flags & (CLIENT_CONTROL|CLIENT_SUSPENDED))
    return;
  if (~c->flags & CLIENT_REDRAWSTATUS)
    return;
  TAILQ_FOREACH(wp, &w->panes, entry) {
    wme = TAILQ_FIRST(&wp->modes);
    if (wme != NULL && wme->mode->update != NULL)
      wme->mode->update(wme);
  }
}

/* Check if any panes need to be redrawn. */
static int
server_client_any_pane_redraw(struct client *c)
{
  struct session    *s = c->session;
  struct window   *w = s->curw->window;
  struct window_pane  *wp;

  if (c->flags & CLIENT_REDRAWWINDOW)
    return (1);
  if (!TAILQ_EMPTY(&w->damage))
    return (1);
  TAILQ_FOREACH(wp, &w->panes, entry) {
    if (wp->flags & (PANE_REDRAW|PANE_REDRAWSCROLLBAR))
      return (1);
  }
  return (0);
}

/* Check for client redraws. */
static void
server_client_check_redraw(struct client *c)
{
  struct session    *s = c->session;
  struct tty    *tty = &c->tty;
  struct window   *w = s->curw->window;
  struct window_pane  *wp;
  int      needed, tflags, mode = tty->mode;
  int      damaged = !TAILQ_EMPTY(&w->damage);
  struct timeval     tv = { .tv_usec = 1000 };
  static struct event  ev;
  size_t       n;

  if (c->flags & (CLIENT_CONTROL|CLIENT_SUSPENDED))
    return;
  if (c->flags & CLIENT_ALLREDRAWFLAGS) {
    log_debug("%s: redraw%s%s%s%s", c->name,
        (c->flags & CLIENT_REDRAWWINDOW) ? " window" : "",
        (c->flags & CLIENT_REDRAWSTATUS) ? " status" : "",
        (c->flags & CLIENT_REDRAWBORDERS) ? " borders" : "",
        (c->flags & CLIENT_REDRAWMENU) ? " menu" : "");
  }

  /* Work out if a redraw is actually needed. */
  needed = 0;
  if (c->flags & (CLIENT_ALLREDRAWFLAGS|CLIENT_REDRAWSCROLLBARS))
    needed = 1;
  else if (server_client_any_pane_redraw(c))
    needed = 1;
  if (!needed) {
    c->flags &= ~CLIENT_STATUSFORCE;
    return;
  }

  /* Ignore output queued within the current synchronized frame. */
  n = EVBUFFER_LENGTH(tty->out);
  if ((tty->flags & TTY_SYNCING) && n > tty->sync_offset)
    n = tty->sync_offset;

  /* Defer until output drains, preserving damage in client flags. */
  if (n != 0 || (tty->flags & TTY_BLOCK)) {
    if (n != 0)
      log_debug("%s: redraw deferred (%zu left)", c->name, n);
    else
      log_debug("%s: redraw deferred (blocked)", c->name);
    if (!evtimer_initialized(&ev))
      evtimer_set(&ev, server_client_redraw_timer, NULL);
    if (!evtimer_pending(&ev, NULL)) {
      log_debug("redraw timer started");
      evtimer_add(&ev, &tv);
    }
    if (damaged) {
      c->flags |= CLIENT_REDRAWWINDOW;
      return;
    }
    TAILQ_FOREACH(wp, &w->panes, entry) {
      if (wp->flags & PANE_REDRAW) {
        c->flags |= CLIENT_REDRAWWINDOW;
        break;
      }
      if (wp->flags & PANE_REDRAWSCROLLBAR)
        c->flags |= CLIENT_REDRAWSCROLLBARS;
    }
    return;
  }

  /* Unfreeze the tty and turn off the cursor. */
  log_debug("%s: redraw needed", c->name);
  tflags = tty->flags & (TTY_BLOCK|TTY_FREEZE|TTY_NOCURSOR);
  tty->flags = (tty->flags & ~(TTY_BLOCK|TTY_FREEZE))|TTY_NOCURSOR;

  /*
   * If not redrawing the entire window, check whether each pane needs to
   * be redrawn.
   */
  if (~c->flags & CLIENT_REDRAWWINDOW) {
    TAILQ_FOREACH(wp, &w->panes, entry) {
      if (wp->flags & PANE_REDRAW) {
        log_debug("%s: redraw pane %%%u", __func__,
            wp->id);
        redraw_pane(c, wp);
      } else if ((wp->flags & PANE_REDRAWSCROLLBAR) ||
          (c->flags & CLIENT_REDRAWSCROLLBARS)) {
        log_debug("%s: redraw scrollbar %%%u", __func__,
            wp->id);
        redraw_pane_scrollbar(c, wp);
      }
    }

    /* Draw damage here if no client redraw flags will handle it. */
    if (damaged && (c->flags & CLIENT_ALLREDRAWFLAGS) == 0)
      redraw_client_damage(c);
  }

  /*
   * Set titles etc and do the redraw if there are redraw flags (and we
   * aren't here just to redraw panes).
   */
  if (c->flags & CLIENT_ALLREDRAWFLAGS) {
    if (options_get_number(s->options, "set-titles")) {
      server_client_set_title(c);
      server_client_set_path(c);
    }
    server_client_set_progress_bar(c);
    redraw_screen(c);
    redraw_client_damage(c);
  }

  /* Put the tty back how it was. */
  tty->flags = (tty->flags & ~TTY_NOCURSOR)|(tflags & TTY_NOCURSOR);
  tty_update_mode(tty, mode, NULL);
  tty->flags = (tty->flags & ~(TTY_BLOCK|TTY_FREEZE|TTY_NOCURSOR))|tflags;

  /*
   * All the redraw flags can now be cleared. Also record how many bytes
   * were written.
   */
  c->flags &= ~(CLIENT_ALLREDRAWFLAGS|CLIENT_REDRAWSCROLLBARS|
      CLIENT_STATUSFORCE);
  c->redraw = EVBUFFER_LENGTH(tty->out);
  log_debug("%s: redraw added %zu bytes", c->name, c->redraw);
}

/* Set client title. */
static void
server_client_set_title(struct client *c)
{
  struct session    *s = c->session;
  const char    *template;
  char      *title;
  struct format_tree  *ft;

  template = options_get_string(s->options, "set-titles-string");

  ft = format_create(c, NULL, FORMAT_NONE, 0);
  format_defaults(ft, c, NULL, NULL, NULL);

  title = format_expand_time(ft, template);
  if (c->title == NULL || strcmp(title, c->title) != 0) {
    free(c->title);
    c->title = xstrdup(title);
    tty_set_title(&c->tty, c->title);
  }
  free(title);

  format_free(ft);
}

/* Set client path. */
static void
server_client_set_path(struct client *c)
{
  struct session  *s = c->session;
  const char  *path;

  if (s->curw == NULL || s->curw->window->active == NULL)
    return;
  if (s->curw->window->active->base.path == NULL)
    path = "";
  else
    path = s->curw->window->active->base.path;
  if (c->path == NULL || strcmp(path, c->path) != 0) {
    free(c->path);
    c->path = xstrdup(path);
    tty_set_path(&c->tty, c->path);
  }
}

/* Set client progress bar. */
static void
server_client_set_progress_bar(struct client *c)
{
  struct session    *s = c->session;
  struct progress_bar *pane_pb;

  if (s->curw == NULL || s->curw->window->active == NULL)
    return;
  pane_pb = &s->curw->window->active->base.progress_bar;
  if (pane_pb->state == c->progress_bar.state &&
      pane_pb->progress == c->progress_bar.progress)
    return;
  memcpy(&c->progress_bar, pane_pb, sizeof c->progress_bar);
  tty_set_progress_bar(&c->tty, &c->progress_bar);
}

/* Dispatch message from client. */
static void
server_client_dispatch(struct imsg *imsg, void *arg)
{
  struct client *c = arg;
  ssize_t    datalen;
  struct session  *s;
  u_int    old_sx, old_sy;

  if (c->flags & CLIENT_DEAD)
    return;

  if (imsg == NULL) {
    server_client_lost(c);
    return;
  }

  datalen = imsg->hdr.len - IMSG_HEADER_SIZE;

  switch (imsg->hdr.type) {
  case MSG_IDENTIFY_CLIENTPID:
  case MSG_IDENTIFY_CWD:
  case MSG_IDENTIFY_ENVIRON:
  case MSG_IDENTIFY_FEATURES:
  case MSG_IDENTIFY_FLAGS:
  case MSG_IDENTIFY_LONGFLAGS:
  case MSG_IDENTIFY_STDIN:
  case MSG_IDENTIFY_STDOUT:
  case MSG_IDENTIFY_TERM:
  case MSG_IDENTIFY_TERMINFO:
  case MSG_IDENTIFY_TTYNAME:
  case MSG_IDENTIFY_DONE:
    if (server_client_dispatch_identify(c, imsg) != 0)
      goto bad;
    break;
  case MSG_COMMAND:
    if (server_client_dispatch_command(c, imsg) != 0)
      goto bad;
    break;
  case MSG_RESIZE:
    if (datalen != 0)
      goto bad;

    if ((c->flags & CLIENT_CONTROL) || (~c->tty.flags & TTY_OPENED))
      break;
    server_client_update_latest(c);
    old_sx = c->tty.sx;
    old_sy = c->tty.sy;
    tty_resize(&c->tty);
    tty_repeat_requests(&c->tty, 0);
    server_client_apply_resize(c, old_sx, old_sy);
    break;
  case MSG_EXITING:
    if (datalen != 0)
      goto bad;
    server_client_set_session(c, NULL);
    recalculate_sizes();
    tty_close(&c->tty);
    proc_send(c->peer, MSG_EXITED, -1, NULL, 0);
    break;
  case MSG_WAKEUP:
  case MSG_UNLOCK:
    if (datalen != 0)
      goto bad;

    if (!(c->flags & CLIENT_SUSPENDED))
      break;
    c->flags &= ~CLIENT_SUSPENDED;

    if (c->fd == -1 || c->session == NULL) /* exited already */
      break;
    s = c->session;

    if (gettimeofday(&c->activity_time, NULL) != 0)
      fatal("gettimeofday failed");

    tty_start_tty(&c->tty);
    server_redraw_client(c);
    recalculate_sizes();

    if (s != NULL)
      session_update_activity(s, &c->activity_time);
    break;
  case MSG_SHELL:
    if (datalen != 0)
      goto bad;
    if (server_client_dispatch_shell(c) != 0)
      goto bad;
    break;
  case MSG_WRITE_READY:
    if (file_write_ready(&c->files, imsg) != 0)
      goto bad;
    break;
  case MSG_WRITE_DONE:
    if (file_write_done(&c->files, imsg) != 0)
      goto bad;
    break;
  case MSG_READ:
    if (file_read_data(&c->files, imsg) != 0)
      goto bad;
    break;
  case MSG_READ_DONE:
    if (file_read_done(&c->files, imsg) != 0)
      goto bad;
    break;
  }

  return;

bad:
  log_debug("client %p invalid message type %d", c, imsg->hdr.type);
  proc_kill_peer(c->peer);
}

/* Callback when command is not allowed. */
static enum cmd_retval
server_client_read_only(struct cmdq_item *item, __unused void *data)
{
  cmdq_error(item, "client is read-only");
  return (CMD_RETURN_ERROR);
}

/* Callback for default command. */
static enum cmd_retval
server_client_default_command(struct cmdq_item *item, __unused void *data)
{
  struct client   *c = cmdq_get_client(item);
  struct cmd_list   *cmdlist;
  struct cmdq_item  *new_item;

  cmdlist = options_get_command(global_options, "default-client-command");
  if ((c->flags & CLIENT_READONLY) &&
      !cmd_list_all_have(cmdlist, CMD_READONLY))
    new_item = cmdq_get_callback(server_client_read_only, NULL);
  else
    new_item = cmdq_get_command(cmdlist, NULL);
  cmdq_insert_after(item, new_item);
  return (CMD_RETURN_NORMAL);
}

/* Callback when command is done. */
static enum cmd_retval
server_client_command_done(struct cmdq_item *item, __unused void *data)
{
  struct client *c = cmdq_get_client(item);

  if (~c->flags & CLIENT_ATTACHED)
    c->flags |= CLIENT_EXIT;
  else if (~c->flags & CLIENT_EXIT) {
    if (c->flags & CLIENT_CONTROL)
      control_ready(c);
    tty_send_requests(&c->tty);
  }
  return (CMD_RETURN_NORMAL);
}

/* Handle command message. */
static int
server_client_dispatch_command(struct client *c, struct imsg *imsg)
{
  struct msg_command    data;
  char       *buf;
  size_t        len;
  int       argc = 0;
  char      **argv, *cause;
  struct cmd_parse_result  *pr;
  struct args_value  *values;
  struct cmdq_item   *new_item;

  if (c->flags & CLIENT_EXIT)
    return (0);

  if (imsg->hdr.len - IMSG_HEADER_SIZE < sizeof data)
    return (-1);
  memcpy(&data, imsg->data, sizeof data);

  buf = (char *)imsg->data + sizeof data;
  len = imsg->hdr.len - IMSG_HEADER_SIZE - sizeof data;
  if (len > 0 && buf[len - 1] != '\0')
    return (-1);

  if (cmd_unpack_argv(buf, len, data.argc, &argv) != 0) {
    cause = xstrdup("command too long");
    goto error;
  }

  argc = data.argc;
  if (argc == 0) {
    new_item = cmdq_get_callback(server_client_default_command,
        NULL);
  } else {
    values = args_from_vector(argc, argv);
    pr = cmd_parse_from_arguments(values, argc, NULL);
    args_free_values(values, argc);
    free(values);
    switch (pr->status) {
    case CMD_PARSE_ERROR:
      cause = pr->error;
      goto error;
    case CMD_PARSE_SUCCESS:
      break;
    }
    cmd_free_argv(argc, argv);
    if ((c->flags & CLIENT_READONLY) &&
        !cmd_list_all_have(pr->cmdlist, CMD_READONLY)) {
      new_item = cmdq_get_callback(server_client_read_only,
          NULL);
    } else
      new_item = cmdq_get_command(pr->cmdlist, NULL);
    cmd_list_free(pr->cmdlist);
  }
  cmdq_append(c, new_item);
  cmdq_append(c, cmdq_get_callback(server_client_command_done, NULL));

  return (0);

error:
  cmd_free_argv(argc, argv);

  cmdq_append(c, cmdq_get_error(cause));
  free(cause);

  c->flags |= CLIENT_EXIT;
  return (0);
}

/* Handle identify message. */
static int
server_client_dispatch_identify(struct client *c, struct imsg *imsg)
{
  const char  *data, *home;
  size_t     datalen;
  int    flags, feat;
  uint64_t   longflags;
  char    *name;

  if (c->flags & CLIENT_IDENTIFIED)
    return (-1);

  data = imsg->data;
  datalen = imsg->hdr.len - IMSG_HEADER_SIZE;

  switch (imsg->hdr.type) {
  case MSG_IDENTIFY_FEATURES:
    if (datalen != sizeof feat)
      return (-1);
    memcpy(&feat, data, sizeof feat);
    c->term_features |= feat;
    log_debug("client %p IDENTIFY_FEATURES %s", c,
        tty_get_features(feat));
    break;
  case MSG_IDENTIFY_FLAGS:
    if (datalen != sizeof flags)
      return (-1);
    memcpy(&flags, data, sizeof flags);
    c->flags |= flags;
    log_debug("client %p IDENTIFY_FLAGS %#x", c, flags);
    break;
  case MSG_IDENTIFY_LONGFLAGS:
    if (datalen != sizeof longflags)
      return (-1);
    memcpy(&longflags, data, sizeof longflags);
    c->flags |= longflags;
    log_debug("client %p IDENTIFY_LONGFLAGS %#llx", c,
        (unsigned long long)longflags);
    break;
  case MSG_IDENTIFY_TERM:
    if (datalen == 0 || data[datalen - 1] != '\0')
      return (-1);
    c->term_name = xstrdup(data);
    log_debug("client %p IDENTIFY_TERM %s", c, data);
    break;
  case MSG_IDENTIFY_TERMINFO:
    if (datalen == 0 || data[datalen - 1] != '\0')
      return (-1);
    c->term_caps = xreallocarray(c->term_caps, c->term_ncaps + 1,
        sizeof *c->term_caps);
    c->term_caps[c->term_ncaps++] = xstrdup(data);
    log_debug("client %p IDENTIFY_TERMINFO %s", c, data);
    break;
  case MSG_IDENTIFY_TTYNAME:
    if (datalen == 0 || data[datalen - 1] != '\0')
      return (-1);
    c->ttyname = xstrdup(data);
    log_debug("client %p IDENTIFY_TTYNAME %s", c, data);
    break;
  case MSG_IDENTIFY_CWD:
    if (datalen == 0 || data[datalen - 1] != '\0')
      return (-1);
    if (access(data, X_OK) == 0)
      c->cwd = xstrdup(data);
    else if ((home = find_home()) != NULL)
      c->cwd = xstrdup(home);
    else
      c->cwd = xstrdup("/");
    log_debug("client %p IDENTIFY_CWD %s", c, data);
    break;
  case MSG_IDENTIFY_STDIN:
    if (datalen != 0)
      return (-1);
    c->fd = imsg_get_fd(imsg);
    log_debug("client %p IDENTIFY_STDIN %d", c, c->fd);
    break;
  case MSG_IDENTIFY_STDOUT:
    if (datalen != 0)
      return (-1);
    c->out_fd = imsg_get_fd(imsg);
    log_debug("client %p IDENTIFY_STDOUT %d", c, c->out_fd);
    break;
  case MSG_IDENTIFY_ENVIRON:
    if (datalen == 0 || data[datalen - 1] != '\0')
      return (-1);
    if (strchr(data, '=') != NULL)
      environ_put(c->environ, data, 0);
    log_debug("client %p IDENTIFY_ENVIRON %s", c, data);
    break;
  case MSG_IDENTIFY_CLIENTPID:
    if (datalen != sizeof c->pid)
      return (-1);
    memcpy(&c->pid, data, sizeof c->pid);
    log_debug("client %p IDENTIFY_CLIENTPID %ld", c, (long)c->pid);
    break;
  default:
    break;
  }

  if (imsg->hdr.type != MSG_IDENTIFY_DONE)
    return (0);
  c->flags |= CLIENT_IDENTIFIED;

  if (c->term_name == NULL || *c->term_name == '\0') {
    free(c->term_name);
    c->term_name = xstrdup("unknown");
  }

  if (c->ttyname != NULL && *c->ttyname != '\0')
    name = xstrdup(c->ttyname);
  else
    xasprintf(&name, "client-%ld", (long)c->pid);
  c->name = name;
  log_debug("client %p name is %s", c, c->name);

#ifdef __CYGWIN__
  c->fd = open(c->ttyname, O_RDWR|O_NOCTTY);
  c->out_fd = dup(c->fd);
#endif

  if (c->flags & CLIENT_CONTROL)
    control_start(c);
  else if (c->fd != -1) {
    if (tty_init(&c->tty, c) != 0) {
      close(c->fd);
      c->fd = -1;
    } else {
      tty_resize(&c->tty);
      c->flags |= CLIENT_TERMINAL;
    }
    if (c->out_fd != -1)
      close(c->out_fd);
    c->out_fd = -1;
  }
  if (c->flags & (CLIENT_CONTROL|CLIENT_TERMINAL))
    events_fire_client("client-created", c);

  /* If pasting has taken too long, turn it off. */
  if (c->flags & (CLIENT_BRACKETPASTING|CLIENT_ASSUMEPASTING) &&
      current_time - c->paste_time > CLIENT_PASTE_TIME_LIMIT) {
    log_debug("%s: paste time limit exceeded", c->name);
    c->flags &= ~(CLIENT_BRACKETPASTING|CLIENT_ASSUMEPASTING);
  }

  /*
   * If this is the first client, load configuration files. Any later
   * clients are allowed to continue with their command even if the
   * config has not been loaded - they might have been run from inside it
   */
  if ((~c->flags & CLIENT_EXIT) &&
       !cfg_finished &&
       c == TAILQ_FIRST(&clients))
    start_cfg();

  return (0);
}

/* Handle shell message. */
static int
server_client_dispatch_shell(struct client *c)
{
  const char  *shell;

  shell = options_get_string(global_s_options, "default-shell");
  if (!checkshell(shell))
    shell = _PATH_BSHELL;
  proc_send(c->peer, MSG_SHELL, -1, shell, strlen(shell) + 1);

  proc_kill_peer(c->peer);
  return (0);
}

/* Get client working directory. */
const char *
server_client_get_cwd(struct client *c, struct session *s)
{
  const char  *home;

  if (!cfg_finished && cfg_client != NULL)
    return (cfg_client->cwd);
  if (c != NULL && c->session == NULL && c->cwd != NULL)
    return (c->cwd);
  if (s != NULL && s->cwd != NULL)
    return (s->cwd);
  if (c != NULL && (s = c->session) != NULL && s->cwd != NULL)
    return (s->cwd);
  if ((home = find_home()) != NULL)
    return (home);
  return ("/");
}

/* Get control client flags. */
static uint64_t
server_client_control_flags(struct client *c, const char *next)
{
  if (strcmp(next, "pause-after") == 0) {
    c->pause_age = 0;
    return (CLIENT_CONTROL_PAUSEAFTER);
  }
  if (sscanf(next, "pause-after=%u", &c->pause_age) == 1) {
    c->pause_age *= 1000;
    return (CLIENT_CONTROL_PAUSEAFTER);
  }
  if (strcmp(next, "no-output") == 0)
    return (CLIENT_CONTROL_NOOUTPUT);
  if (strcmp(next, "wait-exit") == 0)
    return (CLIENT_CONTROL_WAITEXIT);
  if (strcmp(next, "new-layouts") == 0)
    return (CLIENT_CONTROL_NEWLAYOUTS);
  return (0);
}

/* Set client flags. */
void
server_client_set_flags(struct client *c, const char *flags)
{
  char  *s, *copy, *next;
  uint64_t flag;
  int  not;

  s = copy = xstrdup(flags);
  while ((next = strsep(&s, ",")) != NULL) {
    not = (*next == '!');
    if (not)
      next++;

    if (c->flags & CLIENT_CONTROL)
      flag = server_client_control_flags(c, next);
    else
      flag = 0;
    if (strcmp(next, "read-only") == 0)
      flag = CLIENT_READONLY;
    else if (strcmp(next, "ignore-size") == 0)
      flag = CLIENT_IGNORESIZE;
    else if (strcmp(next, "no-detach-on-destroy") == 0)
      flag = CLIENT_NO_DETACH_ON_DESTROY;
    if (flag == 0)
      continue;

    log_debug("client %s set flag %s", c->name, next);
    if (not) {
      if (c->flags & CLIENT_READONLY)
        flag &= ~CLIENT_READONLY;
      c->flags &= ~flag;
    } else
      c->flags |= flag;
    if (flag == CLIENT_CONTROL_NOOUTPUT)
      control_reset_offsets(c);
  }
  free(copy);
  proc_send(c->peer, MSG_FLAGS, -1, &c->flags, sizeof c->flags);
}

/* Get client flags. This is only flags useful to show to users. */
const char *
server_client_get_flags(struct client *c)
{
  static char s[256];
  char    tmp[32];

  *s = '\0';
  if (c->flags & CLIENT_ATTACHED)
    strlcat(s, "attached,", sizeof s);
  if (c->flags & CLIENT_FOCUSED)
    strlcat(s, "focused,", sizeof s);
  if (c->flags & CLIENT_CONTROL)
    strlcat(s, "control-mode,", sizeof s);
  if (c->flags & CLIENT_IGNORESIZE)
    strlcat(s, "ignore-size,", sizeof s);
  if (c->flags & CLIENT_NO_DETACH_ON_DESTROY)
    strlcat(s, "no-detach-on-destroy,", sizeof s);
  if (c->flags & CLIENT_CONTROL_NOOUTPUT)
    strlcat(s, "no-output,", sizeof s);
  if (c->flags & CLIENT_CONTROL_WAITEXIT)
    strlcat(s, "wait-exit,", sizeof s);
  if (c->flags & CLIENT_CONTROL_NEWLAYOUTS)
    strlcat(s, "new-layouts,", sizeof s);
  if (c->flags & CLIENT_CONTROL_PAUSEAFTER) {
    xsnprintf(tmp, sizeof tmp, "pause-after=%u,",
        c->pause_age / 1000);
    strlcat(s, tmp, sizeof s);
  }
  if (c->flags & CLIENT_READONLY)
    strlcat(s, "read-only,", sizeof s);
  if (c->flags & CLIENT_SUSPENDED)
    strlcat(s, "suspended,", sizeof s);
  if (c->flags & CLIENT_UTF8)
    strlcat(s, "UTF-8,", sizeof s);
  if (*s != '\0')
    s[strlen(s) - 1] = '\0';
  return (s);
}

/* Remove pane from client state. */
void
server_client_remove_pane(struct window_pane *wp)
{
  struct client     *c;

  TAILQ_FOREACH(c, &clients, entry) {
    if (c->tty.mouse_last_pane == (int)wp->id) {
      c->tty.mouse_last_pane = -1;
      c->tty.mouse_drag_update = NULL;
      c->tty.mouse_scrolling_flag = 0;
    }
  }
}

/* Print to a client. */
void
server_client_print(struct client *c, int parse, struct evbuffer *evb)
{
  void        *data = EVBUFFER_DATA(evb);
  size_t         size = EVBUFFER_LENGTH(evb);
  struct window_pane    *wp;
  struct window_mode_entry  *wme;
  char        *sanitized, *msg, *line, empty = '\0';

  if (!parse) {
    utf8_stravisx(&msg, data, size,
        VIS_OCTAL|VIS_CSTYLE|VIS_NOSLASH);
  } else {
    if (size == 0)
      msg = &empty;
    else {
      msg = EVBUFFER_DATA(evb);
      if (msg[size - 1] != '\0')
        evbuffer_add(evb, "", 1);
    }
  }
  log_debug("%s: %s", __func__, msg);

  if (c == NULL)
    goto out;

  if (c->session == NULL || (c->flags & CLIENT_CONTROL)) {
    if (~c->flags & CLIENT_UTF8) {
      sanitized = utf8_sanitize(msg);
      if (c->flags & CLIENT_CONTROL)
        control_write(c, "%s", sanitized);
      else
        file_print(c, "%s\n", sanitized);
      free(sanitized);
    } else {
      if (c->flags & CLIENT_CONTROL)
        control_write(c, "%s", msg);
      else
        file_print(c, "%s\n", msg);
    }
    goto out;
  }

  wp = c->session->curw->window->active;
  wme = TAILQ_FIRST(&wp->modes);
  if (wme == NULL || wme->mode != &window_view_mode)
    window_pane_set_mode(wp, NULL, &window_view_mode, NULL, NULL,
        NULL);
  if (parse) {
    do {
      line = evbuffer_readln(evb, NULL, EVBUFFER_EOL_LF);
      if (line != NULL) {
        window_copy_add(wp, 1, "%s", line);
        free(line);
      }
    } while (line != NULL);

    size = EVBUFFER_LENGTH(evb);
    if (size != 0) {
      line = EVBUFFER_DATA(evb);
      window_copy_add(wp, 1, "%.*s", (int)size, line);
    }
  } else
    window_copy_add(wp, 0, "%s", msg);

out:
  if (!parse)
    free(msg);
}

static void
server_client_report_theme(struct client *c, enum client_theme theme)
{
  enum client_theme  old = c->theme;

  if (theme == THEME_LIGHT) {
    c->theme = THEME_LIGHT;
    events_fire_client("client-light-theme", c);
  } else {
    c->theme = THEME_DARK;
    events_fire_client("client-dark-theme", c);
  }

  /*
   * If the theme has changed, update the theme colours and redraw the
   * client.
   */
  if (c->theme != old) {
    server_client_update_theme_colours(c);
    if (c->tty.flags & TTY_OPENED)
      tty_invalidate(&c->tty);
    server_redraw_client(c);
  }

  /*
   * Request foreground and background colour again. Don't forward 2031 to
   * panes until a response is received.
   */
  tty_repeat_requests(&c->tty, 1);
}

Coverage Report

Created: 2026-10-28 06:08