/* 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; }