histsearch.c
上传用户:tsgydb
上传日期:2007-04-14
资源大小:10674k
文件大小:5k
- /* 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 == ' ')
- 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;
- }