/* 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 2, 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,   59 Temple Place, Suite 330, Boston, MA 02111 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#include "history.h"#include "histlib.h"/* The list of alternate characters that can delimit a history search   string. */char *history_search_delimiter_chars = (char *)NULL;static int history_search_internal PARAMS((const char *, int, int));/* 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 inthistory_search_internal (string, direction, anchored)     const 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. */inthistory_search (string, direction)     const char *string;     int direction;{  return (history_search_internal (string, direction, NON_ANCHORED_SEARCH));}/* Do an anchored search for string through the history in DIRECTION. */inthistory_search_prefix (string, direction)     const 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. */inthistory_search_pos (string, dir, pos)     const 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;}