/* isearch.c - incremental searching */

/* **************************************************************** */
/*								    */
/*			I-Search and Searching			    */
/*								    */
/* **************************************************************** */

/* Copyright (C) 1987-2012 Free Software Foundation, Inc.

   This file is part of the GNU Readline Library (Readline), a library
   for reading lines of text with interactive input and history editing.      

   Readline is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   Readline is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with Readline.  If not, see <http://www.gnu.org/licenses/>.
*/

#define READLINE_LIBRARY

#if defined (HAVE_CONFIG_H)
#  include <config.h>
#endif

#include <sys/types.h>

#include <stdio.h>

#if defined (HAVE_UNISTD_H)
#  include <unistd.h>
#endif

#if defined (HAVE_STDLIB_H)
#  include <stdlib.h>
#else
#  include "ansi_stdlib.h"
#endif

#include "rldefs.h"
#include "rlmbutil.h"

#include "readline.h"
#include "history.h"

#include "rlprivate.h"
#include "xmalloc.h"

/* Variables exported to other files in the readline library. */
char *_rl_isearch_terminators = (char *)NULL;

_rl_search_cxt *_rl_iscxt = 0;

/* Variables imported from other files in the readline library. */
extern HIST_ENTRY *_rl_saved_line_for_history;

static int rl_search_history PARAMS((int, int));

static _rl_search_cxt *_rl_isearch_init PARAMS((int));
static void _rl_isearch_fini PARAMS((_rl_search_cxt *));
static int _rl_isearch_cleanup PARAMS((_rl_search_cxt *, int));

/* Last line found by the current incremental search, so we don't `find'
   identical lines many times in a row.  Now part of isearch context. */
/* static char *prev_line_found; */

/* Last search string and its length. */
static char *last_isearch_string;
static int last_isearch_string_len;

static char * const default_isearch_terminators = "\033\012";

_rl_search_cxt *
_rl_scxt_alloc (type, flags)
     int type, flags;
{
  _rl_search_cxt *cxt;

  cxt = (_rl_search_cxt *)xmalloc (sizeof (_rl_search_cxt));

  cxt->type = type;
  cxt->sflags = flags;

  cxt->search_string = 0;
  cxt->search_string_size = cxt->search_string_index = 0;

  cxt->lines = 0;
  cxt->allocated_line = 0;
  cxt->hlen = cxt->hindex = 0;

  cxt->save_point = rl_point;
  cxt->save_mark = rl_mark;
  cxt->save_line = where_history ();
  cxt->last_found_line = cxt->save_line;
  cxt->prev_line_found = 0;

  cxt->save_undo_list = 0;

  cxt->keymap = _rl_keymap;
  cxt->okeymap = _rl_keymap;

  cxt->history_pos = 0;
  cxt->direction = 0;

  cxt->prevc = cxt->lastc = 0;

  cxt->sline = 0;
  cxt->sline_len = cxt->sline_index = 0;

  cxt->search_terminators = 0;

  return cxt;
}

void
_rl_scxt_dispose (cxt, flags)
     _rl_search_cxt *cxt;
     int flags;
{
  FREE (cxt->search_string);
  FREE (cxt->allocated_line);
  FREE (cxt->lines);

  xfree (cxt);
}

/* Search backwards through the history looking for a string which is typed
   interactively.  Start with the current line. */
int
rl_reverse_search_history (sign, key)
     int sign, key;
{
  return (rl_search_history (-sign, key));
}

/* Search forwards through the history looking for a string which is typed
   interactively.  Start with the current line. */
int
rl_forward_search_history (sign, key)
     int sign, key;
{
  return (rl_search_history (sign, key));
}

/* Display the current state of the search in the echo-area.
   SEARCH_STRING contains the string that is being searched for,
   DIRECTION is zero for forward, or non-zero for reverse,
   WHERE is the history list number of the current line.  If it is
   -1, then this line is the starting one. */
static void
rl_display_search (search_string, reverse_p, where)
     char *search_string;
     int reverse_p, where;
{
  char *message;
  int msglen, searchlen;

  searchlen = (search_string && *search_string) ? strlen (search_string) : 0;

  message = (char *)xmalloc (searchlen + 33);
  msglen = 0;

#if defined (NOTDEF)
  if (where != -1)
    {
      sprintf (message, "[%d]", where + history_base);
      msglen = strlen (message);
    }
#endif /* NOTDEF */

  message[msglen++] = '(';

  if (reverse_p)
    {
      strcpy (message + msglen, "reverse-");
      msglen += 8;
    }

  strcpy (message + msglen, "i-search)`");
  msglen += 10;

  if (search_string)
    {
      strcpy (message + msglen, search_string);
      msglen += searchlen;
    }

  strcpy (message + msglen, "': ");

  rl_message ("%s", message);
  xfree (message);
  (*rl_redisplay_function) ();
}

static _rl_search_cxt *
_rl_isearch_init (direction)
     int direction;
{
  _rl_search_cxt *cxt;
  register int i;
  HIST_ENTRY **hlist;

  cxt = _rl_scxt_alloc (RL_SEARCH_ISEARCH, 0);
  if (direction < 0)
    cxt->sflags |= SF_REVERSE;

  cxt->search_terminators = _rl_isearch_terminators ? _rl_isearch_terminators
						: default_isearch_terminators;

  /* Create an arrary of pointers to the lines that we want to search. */
  hlist = history_list ();
  rl_maybe_replace_line ();
  i = 0;
  if (hlist)
    for (i = 0; hlist[i]; i++);

  /* Allocate space for this many lines, +1 for the current input line,
     and remember those lines. */
  cxt->lines = (char **)xmalloc ((1 + (cxt->hlen = i)) * sizeof (char *));
  for (i = 0; i < cxt->hlen; i++)
    cxt->lines[i] = hlist[i]->line;

  if (_rl_saved_line_for_history)
    cxt->lines[i] = _rl_saved_line_for_history->line;
  else
    {
      /* Keep track of this so we can free it. */
      cxt->allocated_line = (char *)xmalloc (1 + strlen (rl_line_buffer));
      strcpy (cxt->allocated_line, &rl_line_buffer[0]);
      cxt->lines[i] = cxt->allocated_line;
    }

  cxt->hlen++;

  /* The line where we start the search. */
  cxt->history_pos = cxt->save_line;

  rl_save_prompt ();

  /* Initialize search parameters. */
  cxt->search_string = (char *)xmalloc (cxt->search_string_size = 128);
  cxt->search_string[cxt->search_string_index = 0] = '\0';

  /* Normalize DIRECTION into 1 or -1. */
  cxt->direction = (direction >= 0) ? 1 : -1;

  cxt->sline = rl_line_buffer;
  cxt->sline_len = strlen (cxt->sline);
  cxt->sline_index = rl_point;

  _rl_iscxt = cxt;		/* save globally */

  return cxt;
}

static void
_rl_isearch_fini (cxt)
     _rl_search_cxt *cxt;
{
  /* First put back the original state. */
  strcpy (rl_line_buffer, cxt->lines[cxt->save_line]);

  rl_restore_prompt ();

  /* Save the search string for possible later use. */
  FREE (last_isearch_string);
  last_isearch_string = cxt->search_string;
  last_isearch_string_len = cxt->search_string_index;
  cxt->search_string = 0;

  if (cxt->last_found_line < cxt->save_line)
    rl_get_previous_history (cxt->save_line - cxt->last_found_line, 0);
  else
    rl_get_next_history (cxt->last_found_line - cxt->save_line, 0);

  /* If the string was not found, put point at the end of the last matching
     line.  If last_found_line == orig_line, we didn't find any matching
     history lines at all, so put point back in its original position. */
  if (cxt->sline_index < 0)
    {
      if (cxt->last_found_line == cxt->save_line)
	cxt->sline_index = cxt->save_point;
      else
	cxt->sline_index = strlen (rl_line_buffer);
      rl_mark = cxt->save_mark;
    }

  rl_point = cxt->sline_index;
  /* Don't worry about where to put the mark here; rl_get_previous_history
     and rl_get_next_history take care of it. */

  rl_clear_message ();
}

int
_rl_search_getchar (cxt)
     _rl_search_cxt *cxt;
{
  int c;

  /* Read a key and decide how to proceed. */
  RL_SETSTATE(RL_STATE_MOREINPUT);
  c = cxt->lastc = rl_read_key ();
  RL_UNSETSTATE(RL_STATE_MOREINPUT);

#if defined (HANDLE_MULTIBYTE)
  /* This ends up with C (and LASTC) being set to the last byte of the
     multibyte character.  In most cases c == lastc == mb[0] */
  if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
    c = cxt->lastc = _rl_read_mbstring (cxt->lastc, cxt->mb, MB_LEN_MAX);
#endif

  RL_CHECK_SIGNALS ();
  return c;
}

#define ENDSRCH_CHAR(c) \
  ((CTRL_CHAR (c) || META_CHAR (c) || (c) == RUBOUT) && ((c) != CTRL ('G')))

/* Process just-read character C according to isearch context CXT.  Return
   -1 if the caller should just free the context and return, 0 if we should
   break out of the loop, and 1 if we should continue to read characters. */
int
_rl_isearch_dispatch (cxt, c)
     _rl_search_cxt *cxt;
     int c;
{
  int n, wstart, wlen, limit, cval;
  rl_command_func_t *f;

  f = (rl_command_func_t *)NULL;

  if (c < 0)
    {
      cxt->sflags |= SF_FAILED;
      cxt->history_pos = cxt->last_found_line;
      return -1;
    }

  /* If we are moving into a new keymap, modify cxt->keymap and go on.
     This can be a problem if c == ESC and we want to terminate the
     incremental search, so we check */
  if (c >= 0 && cxt->keymap[c].type == ISKMAP && strchr (cxt->search_terminators, cxt->lastc) == 0)
    {
      /* _rl_keyseq_timeout specified in milliseconds; _rl_input_queued
	 takes microseconds, so multiply by 1000.  If we don't get any
	 additional input and we this keymap shadows another function, process
	 that key as if it was all we read. */
      if (_rl_keyseq_timeout > 0 &&
	    RL_ISSTATE (RL_STATE_CALLBACK) == 0 &&
	    RL_ISSTATE (RL_STATE_INPUTPENDING) == 0 &&
	    _rl_pushed_input_available () == 0 &&
	    ((Keymap)(cxt->keymap[c].function))[ANYOTHERKEY].function &&
	    _rl_input_queued (_rl_keyseq_timeout*1000) == 0)
	goto add_character;

      cxt->okeymap = cxt->keymap;
      cxt->keymap = FUNCTION_TO_KEYMAP (cxt->keymap, c);
      cxt->sflags |= SF_CHGKMAP;
      /* XXX - we should probably save this sequence, so we can do
	 something useful if this doesn't end up mapping to a command we
	 interpret here.  Right now we just save the most recent character
	 that caused the index into a new keymap. */
      cxt->prevc = c;
#if defined (HANDLE_MULTIBYTE)
      if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
	{
	  if (cxt->mb[1] == 0)
	    {
	      cxt->pmb[0] = c;		/* XXX should be == cxt->mb[0] */
	      cxt->pmb[1] = '\0';
	    }
	  else
	    memcpy (cxt->pmb, cxt->mb, sizeof (cxt->pmb));
	}
#endif
      return 1;
    }

add_character:

  /* Translate the keys we do something with to opcodes. */
  if (c >= 0 && cxt->keymap[c].type == ISFUNC)
    {
      f = cxt->keymap[c].function;

      if (f == rl_reverse_search_history)
	cxt->lastc = (cxt->sflags & SF_REVERSE) ? -1 : -2;
      else if (f == rl_forward_search_history)
	cxt->lastc = (cxt->sflags & SF_REVERSE) ? -2 : -1;
      else if (f == rl_rubout)
	cxt->lastc = -3;
      else if (c == CTRL ('G') || f == rl_abort)
	cxt->lastc = -4;
      else if (c == CTRL ('W') || f == rl_unix_word_rubout)	/* XXX */
	cxt->lastc = -5;
      else if (c == CTRL ('Y') || f == rl_yank)	/* XXX */
	cxt->lastc = -6;
    }

  /* If we changed the keymap earlier while translating a key sequence into
     a command, restore it now that we've succeeded. */
  if (cxt->sflags & SF_CHGKMAP)
    {
      cxt->keymap = cxt->okeymap;
      cxt->sflags &= ~SF_CHGKMAP;
      /* If we indexed into a new keymap, but didn't map to a command that
	 affects the search (lastc > 0), and the character that mapped to a
	 new keymap would have ended the search (ENDSRCH_CHAR(cxt->prevc)),
	 handle that now as if the previous char would have ended the search
	 and we would have read the current character. */
      /* XXX - should we check cxt->mb? */
      if (cxt->lastc > 0 && ENDSRCH_CHAR (cxt->prevc))
	{
	  rl_stuff_char (cxt->lastc);
	  rl_execute_next (cxt->prevc);
	  /* XXX - do we insert everything in cxt->pmb? */
	  return (0);
	}
      /* Otherwise, if the current character is mapped to self-insert or
	 nothing (i.e., not an editing command), and the previous character
	 was a keymap index, then we need to insert both the previous
	 character and the current character into the search string. */
      else if (cxt->lastc > 0 && cxt->prevc > 0 &&
	       cxt->keymap[cxt->prevc].type == ISKMAP &&
	       (f == 0 || f == rl_insert))
	{
	  /* Make lastc be the next character read */
	  /* XXX - do we insert everything in cxt->mb? */
	  rl_execute_next (cxt->lastc);
	  /* Dispatch on the previous character (insert into search string) */
	  cxt->lastc = cxt->prevc;
#if defined (HANDLE_MULTIBYTE)
	  /* Have to overwrite cxt->mb here because dispatch uses it below */
	  if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
	    {  
	      if (cxt->pmb[1] == 0)	  
		{
		  cxt->mb[0] = cxt->lastc;	/* == cxt->prevc */
		  cxt->mb[1] = '\0';
		}
	      else
		memcpy (cxt->mb, cxt->pmb, sizeof (cxt->mb));
	    }
#endif
	  cxt->prevc = 0;	  
	}
      else if (cxt->lastc > 0 && cxt->prevc > 0 && f && f != rl_insert)
	{
	  rl_stuff_char (cxt->lastc);
	  rl_execute_next (cxt->prevc);
	  /* XXX - do we insert everything in cxt->pmb? */
	  return (0);
	}
    }

  /* The characters in isearch_terminators (set from the user-settable
     variable isearch-terminators) are used to terminate the search but
     not subsequently execute the character as a command.  The default
     value is "\033\012" (ESC and C-J). */
  if (cxt->lastc > 0 && strchr (cxt->search_terminators, cxt->lastc))
    {
      /* ESC still terminates the search, but if there is pending
	 input or if input arrives within 0.1 seconds (on systems
	 with select(2)) it is used as a prefix character
	 with rl_execute_next.  WATCH OUT FOR THIS!  This is intended
	 to allow the arrow keys to be used like ^F and ^B are used
	 to terminate the search and execute the movement command.
	 XXX - since _rl_input_available depends on the application-
	 settable keyboard timeout value, this could alternatively
	 use _rl_input_queued(100000) */
      if (cxt->lastc == ESC && _rl_input_available ())
	rl_execute_next (ESC);
      return (0);
    }

#if defined (HANDLE_MULTIBYTE)
  if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
    {
      if (cxt->lastc >= 0 && (cxt->mb[0] && cxt->mb[1] == '\0') && ENDSRCH_CHAR (cxt->lastc))
	{
	  /* This sets rl_pending_input to LASTC; it will be picked up the next
	     time rl_read_key is called. */
	  rl_execute_next (cxt->lastc);
	  return (0);
	}
    }
  else
#endif
    if (cxt->lastc >= 0 && ENDSRCH_CHAR (cxt->lastc))
      {
	/* This sets rl_pending_input to LASTC; it will be picked up the next
	   time rl_read_key is called. */
	rl_execute_next (cxt->lastc);
	return (0);
      }

  /* Now dispatch on the character.  `Opcodes' affect the search string or
     state.  Other characters are added to the string.  */
  switch (cxt->lastc)
    {
    /* search again */
    case -1:
      if (cxt->search_string_index == 0)
	{
	  if (last_isearch_string)
	    {
	      cxt->search_string_size = 64 + last_isearch_string_len;
	      cxt->search_string = (char *)xrealloc (cxt->search_string, cxt->search_string_size);
	      strcpy (cxt->search_string, last_isearch_string);
	      cxt->search_string_index = last_isearch_string_len;
	      rl_display_search (cxt->search_string, (cxt->sflags & SF_REVERSE), -1);
	      break;
	    }
	  return (1);
	}
      else if (cxt->sflags & SF_REVERSE)
	cxt->sline_index--;
      else if (cxt->sline_index != cxt->sline_len)
	cxt->sline_index++;
      else
	rl_ding ();
      break;

    /* switch directions */
    case -2:
      cxt->direction = -cxt->direction;
      if (cxt->direction < 0)
	cxt->sflags |= SF_REVERSE;
      else
	cxt->sflags &= ~SF_REVERSE;
      break;

    /* delete character from search string. */
    case -3:	/* C-H, DEL */
      /* This is tricky.  To do this right, we need to keep a
	 stack of search positions for the current search, with
	 sentinels marking the beginning and end.  But this will
	 do until we have a real isearch-undo. */
      if (cxt->search_string_index == 0)
	rl_ding ();
      else
	cxt->search_string[--cxt->search_string_index] = '\0';
      break;

    case -4:	/* C-G, abort */
      rl_replace_line (cxt->lines[cxt->save_line], 0);
      rl_point = cxt->save_point;
      rl_mark = cxt->save_mark;
      rl_restore_prompt();
      rl_clear_message ();

      return -1;

    case -5:	/* C-W */
      /* skip over portion of line we already matched and yank word */
      wstart = rl_point + cxt->search_string_index;
      if (wstart >= rl_end)
	{
	  rl_ding ();
	  break;
	}

      /* if not in a word, move to one. */
      cval = _rl_char_value (rl_line_buffer, wstart);
      if (_rl_walphabetic (cval) == 0)
	{
	  rl_ding ();
	  break;
	}
      n = MB_NEXTCHAR (rl_line_buffer, wstart, 1, MB_FIND_NONZERO);;
      while (n < rl_end)
	{
	  cval = _rl_char_value (rl_line_buffer, n);
	  if (_rl_walphabetic (cval) == 0)
	    break;
	  n = MB_NEXTCHAR (rl_line_buffer, n, 1, MB_FIND_NONZERO);;
	}
      wlen = n - wstart + 1;
      if (cxt->search_string_index + wlen + 1 >= cxt->search_string_size)
	{
	  cxt->search_string_size += wlen + 1;
	  cxt->search_string = (char *)xrealloc (cxt->search_string, cxt->search_string_size);
	}
      for (; wstart < n; wstart++)
	cxt->search_string[cxt->search_string_index++] = rl_line_buffer[wstart];
      cxt->search_string[cxt->search_string_index] = '\0';
      break;

    case -6:	/* C-Y */
      /* skip over portion of line we already matched and yank rest */
      wstart = rl_point + cxt->search_string_index;
      if (wstart >= rl_end)
	{
	  rl_ding ();
	  break;
	}
      n = rl_end - wstart + 1;
      if (cxt->search_string_index + n + 1 >= cxt->search_string_size)
	{
	  cxt->search_string_size += n + 1;
	  cxt->search_string = (char *)xrealloc (cxt->search_string, cxt->search_string_size);
	}
      for (n = wstart; n < rl_end; n++)
	cxt->search_string[cxt->search_string_index++] = rl_line_buffer[n];
      cxt->search_string[cxt->search_string_index] = '\0';
      break;

    /* Add character to search string and continue search. */
    default:
      if (cxt->search_string_index + 2 >= cxt->search_string_size)
	{
	  cxt->search_string_size += 128;
	  cxt->search_string = (char *)xrealloc (cxt->search_string, cxt->search_string_size);
	}
#if defined (HANDLE_MULTIBYTE)
      if (MB_CUR_MAX > 1 && rl_byte_oriented == 0)
	{
	  int j, l;

	  if (cxt->mb[0] == 0 || cxt->mb[1] == 0)
	    cxt->search_string[cxt->search_string_index++] = cxt->mb[0];
	  else
	    for (j = 0, l = RL_STRLEN (cxt->mb); j < l; )
	      cxt->search_string[cxt->search_string_index++] = cxt->mb[j++];
	}
      else
#endif
	cxt->search_string[cxt->search_string_index++] = cxt->lastc;	/* XXX - was c instead of lastc */
      cxt->search_string[cxt->search_string_index] = '\0';
      break;
    }

  for (cxt->sflags &= ~(SF_FOUND|SF_FAILED);; )
    {
      limit = cxt->sline_len - cxt->search_string_index + 1;

      /* Search the current line. */
      while ((cxt->sflags & SF_REVERSE) ? (cxt->sline_index >= 0) : (cxt->sline_index < limit))
	{
	  if (STREQN (cxt->search_string, cxt->sline + cxt->sline_index, cxt->search_string_index))
	    {
	      cxt->sflags |= SF_FOUND;
	      break;
	    }
	  else
	    cxt->sline_index += cxt->direction;
	}
      if (cxt->sflags & SF_FOUND)
	break;

      /* Move to the next line, but skip new copies of the line
	 we just found and lines shorter than the string we're
	 searching for. */
      do
	{
	  /* Move to the next line. */
	  cxt->history_pos += cxt->direction;

	  /* At limit for direction? */
	  if ((cxt->sflags & SF_REVERSE) ? (cxt->history_pos < 0) : (cxt->history_pos == cxt->hlen))
	    {
	      cxt->sflags |= SF_FAILED;
	      break;
	    }

	  /* We will need these later. */
	  cxt->sline = cxt->lines[cxt->history_pos];
	  cxt->sline_len = strlen (cxt->sline);
	}
      while ((cxt->prev_line_found && STREQ (cxt->prev_line_found, cxt->lines[cxt->history_pos])) ||
	     (cxt->search_string_index > cxt->sline_len));

      if (cxt->sflags & SF_FAILED)
	break;

      /* Now set up the line for searching... */
      cxt->sline_index = (cxt->sflags & SF_REVERSE) ? cxt->sline_len - cxt->search_string_index : 0;
    }

  if (cxt->sflags & SF_FAILED)
    {
      /* We cannot find the search string.  Ding the bell. */
      rl_ding ();
      cxt->history_pos = cxt->last_found_line;
      return 1;
    }

  /* We have found the search string.  Just display it.  But don't
     actually move there in the history list until the user accepts
     the location. */
  if (cxt->sflags & SF_FOUND)
    {
      cxt->prev_line_found = cxt->lines[cxt->history_pos];
      rl_replace_line (cxt->lines[cxt->history_pos], 0);
      rl_point = cxt->sline_index;
      cxt->last_found_line = cxt->history_pos;
      rl_display_search (cxt->search_string, (cxt->sflags & SF_REVERSE), (cxt->history_pos == cxt->save_line) ? -1 : cxt->history_pos);
    }

  return 1;
}

static int
_rl_isearch_cleanup (cxt, r)
     _rl_search_cxt *cxt;
     int r;
{
  if (r >= 0)
    _rl_isearch_fini (cxt);
  _rl_scxt_dispose (cxt, 0);
  _rl_iscxt = 0;

  RL_UNSETSTATE(RL_STATE_ISEARCH);

  return (r != 0);
}

/* Search through the history looking for an interactively typed string.
   This is analogous to i-search.  We start the search in the current line.
   DIRECTION is which direction to search; >= 0 means forward, < 0 means
   backwards. */
static int
rl_search_history (direction, invoking_key)
     int direction, invoking_key;
{
  _rl_search_cxt *cxt;		/* local for now, but saved globally */
  int c, r;

  RL_SETSTATE(RL_STATE_ISEARCH);
  cxt = _rl_isearch_init (direction);

  rl_display_search (cxt->search_string, (cxt->sflags & SF_REVERSE), -1);

  /* If we are using the callback interface, all we do is set up here and
      return.  The key is that we leave RL_STATE_ISEARCH set. */
  if (RL_ISSTATE (RL_STATE_CALLBACK))
    return (0);

  r = -1;
  for (;;)
    {
      c = _rl_search_getchar (cxt);
      /* We might want to handle EOF here (c == 0) */
      r = _rl_isearch_dispatch (cxt, cxt->lastc);
      if (r <= 0)
        break;
    }

  /* The searching is over.  The user may have found the string that she
     was looking for, or else she may have exited a failing search.  If
     LINE_INDEX is -1, then that shows that the string searched for was
     not found.  We use this to determine where to place rl_point. */
  return (_rl_isearch_cleanup (cxt, r));
}

#if defined (READLINE_CALLBACKS)
/* Called from the callback functions when we are ready to read a key.  The
   callback functions know to call this because RL_ISSTATE(RL_STATE_ISEARCH).
   If _rl_isearch_dispatch finishes searching, this function is responsible
   for turning off RL_STATE_ISEARCH, which it does using _rl_isearch_cleanup. */
int
_rl_isearch_callback (cxt)
     _rl_search_cxt *cxt;
{
  int c, r;

  c = _rl_search_getchar (cxt);
  /* We might want to handle EOF here */
  r = _rl_isearch_dispatch (cxt, cxt->lastc);

  return (r <= 0) ? _rl_isearch_cleanup (cxt, r) : 0;
}
#endif