Subversion Repositories or1k

/* histsearch.c -- searching the history list. */

/* Copyright (C) 1989, 1992 Free Software Foundation, Inc.

   This file contains the GNU History Library (the Library), a set of

   routines for managing the text of previously typed lines.

   The Library 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 1, or (at your option)

   any later version.

   The Library 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.

   The GNU General Public License is often shipped with GNU software, and

   is generally kept in a file called COPYING or LICENSE.  If you do not

   have a copy of the license, write to the Free Software Foundation,

   675 Mass Ave, Cambridge, MA 02139, USA. */

#define READLINE_LIBRARY

#if defined (HAVE_CONFIG_H)

#  include <config.h>

#endif

#include <stdio.h>

#if defined (HAVE_STDLIB_H)

#  include <stdlib.h>

#else

#  include "ansi_stdlib.h"

#endif /* HAVE_STDLIB_H */

#if defined (HAVE_UNISTD_H)

#  ifdef _MINIX

#    include <sys/types.h>

#  endif

#  include <unistd.h>

#endif

#if defined (HAVE_STRING_H)

#  include <string.h>

#else

#  include <strings.h>

#endif /* !HAVE_STRING_H */

#include "history.h"

#include "histlib.h"

/* Variables imported from other history library files. */

extern int history_offset;

/* The list of alternate characters that can delimit a history search

   string. */

char *history_search_delimiter_chars = (char *)NULL;

/* Search the history for STRING, starting at history_offset.

   If DIRECTION < 0, then the search is through previous entries, else

   through subsequent.  If ANCHORED is non-zero, the string must

   appear at the beginning of a history line, otherwise, the string

   may appear anywhere in the line.  If the string is found, then

   current_history () is the history entry, and the value of this

   function is the offset in the line of that history entry that the

   string was found in.  Otherwise, nothing is changed, and a -1 is

   returned. */

static int

history_search_internal (string, direction, anchored)

     char *string;

     int direction, anchored;

{

  register int i, reverse;

  register char *line;

  register int line_index;

  int string_len;

  HIST_ENTRY **the_history;     /* local */

  i = history_offset;

  reverse = (direction < 0);

  /* Take care of trivial cases first. */

  if (string == 0 || *string == '\0')

    return (-1);

  if (!history_length || ((i == history_length) && !reverse))

    return (-1);

  if (reverse && (i == history_length))

    i--;

#define NEXT_LINE() do { if (reverse) i--; else i++; } while (0)

  the_history = history_list ();

  string_len = strlen (string);

  while (1)

    {

      /* Search each line in the history list for STRING. */

      /* At limit for direction? */

      if ((reverse && i < 0) || (!reverse && i == history_length))

        return (-1);

      line = the_history[i]->line;

      line_index = strlen (line);

      /* If STRING is longer than line, no match. */

      if (string_len > line_index)

        {

          NEXT_LINE ();

          continue;

        }

      /* Handle anchored searches first. */

      if (anchored == ANCHORED_SEARCH)

        {

          if (STREQN (string, line, string_len))

            {

              history_offset = i;

              return (0);

            }

          NEXT_LINE ();

          continue;

        }

      /* Do substring search. */

      if (reverse)

        {

          line_index -= string_len;

          while (line_index >= 0)

            {

              if (STREQN (string, line + line_index, string_len))

                {

                  history_offset = i;

                  return (line_index);

                }

              line_index--;

            }

        }

      else

        {

          register int limit;

          limit = line_index - string_len + 1;

          line_index = 0;

          while (line_index < limit)

            {

              if (STREQN (string, line + line_index, string_len))

                {

                  history_offset = i;

                  return (line_index);

                }

              line_index++;

            }

        }

      NEXT_LINE ();

    }

}

/* Do a non-anchored search for STRING through the history in DIRECTION. */

int

history_search (string, direction)

     char *string;

     int direction;

{

  return (history_search_internal (string, direction, NON_ANCHORED_SEARCH));

}

/* Do an anchored search for string through the history in DIRECTION. */

int

history_search_prefix (string, direction)

     char *string;

     int direction;

{

  return (history_search_internal (string, direction, ANCHORED_SEARCH));

}

/* Search for STRING in the history list.  DIR is < 0 for searching

   backwards.  POS is an absolute index into the history list at

   which point to begin searching. */

int

history_search_pos (string, dir, pos)

     char *string;

     int dir, pos;

{

  int ret, old;

  old = where_history ();

  history_set_pos (pos);

  if (history_search (string, dir) == -1)

    {

      history_set_pos (old);

      return (-1);

    }

  ret = where_history ();

  history_set_pos (old);

  return ret;

}