| 1 | /* histsearch.c -- searching the history list. */ |
| 2 | |
| 3 | /* Copyright (C) 1989, 1992 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file contains the GNU History Library (the Library), a set of |
| 6 | routines for managing the text of previously typed lines. |
| 7 | |
| 8 | The Library is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 2, or (at your option) |
| 11 | any later version. |
| 12 | |
| 13 | The Library is distributed in the hope that it will be useful, but |
| 14 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | General Public License for more details. |
| 17 | |
| 18 | The GNU General Public License is often shipped with GNU software, and |
| 19 | is generally kept in a file called COPYING or LICENSE. If you do not |
| 20 | have a copy of the license, write to the Free Software Foundation, |
| 21 | 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ |
| 22 | |
| 23 | #define READLINE_LIBRARY |
| 24 | |
| 25 | #if defined (HAVE_CONFIG_H) |
| 26 | # include <config.h> |
| 27 | #endif |
| 28 | |
| 29 | #include <stdio.h> |
| 30 | #if defined (HAVE_STDLIB_H) |
| 31 | # include <stdlib.h> |
| 32 | #else |
| 33 | # include "ansi_stdlib.h" |
| 34 | #endif /* HAVE_STDLIB_H */ |
| 35 | |
| 36 | #if defined (HAVE_UNISTD_H) |
| 37 | # ifdef _MINIX |
| 38 | # include <sys/types.h> |
| 39 | # endif |
| 40 | # include <unistd.h> |
| 41 | #endif |
| 42 | |
| 43 | #include "history.h" |
| 44 | #include "histlib.h" |
| 45 | |
| 46 | /* The list of alternate characters that can delimit a history search |
| 47 | string. */ |
| 48 | char *history_search_delimiter_chars = (char *)NULL; |
| 49 | |
| 50 | static int history_search_internal PARAMS((const char *, int, int)); |
| 51 | |
| 52 | /* Search the history for STRING, starting at history_offset. |
| 53 | If DIRECTION < 0, then the search is through previous entries, else |
| 54 | through subsequent. If ANCHORED is non-zero, the string must |
| 55 | appear at the beginning of a history line, otherwise, the string |
| 56 | may appear anywhere in the line. If the string is found, then |
| 57 | current_history () is the history entry, and the value of this |
| 58 | function is the offset in the line of that history entry that the |
| 59 | string was found in. Otherwise, nothing is changed, and a -1 is |
| 60 | returned. */ |
| 61 | |
| 62 | static int |
| 63 | history_search_internal (string, direction, anchored) |
| 64 | const char *string; |
| 65 | int direction, anchored; |
| 66 | { |
| 67 | register int i, reverse; |
| 68 | register char *line; |
| 69 | register int line_index; |
| 70 | int string_len; |
| 71 | HIST_ENTRY **the_history; /* local */ |
| 72 | |
| 73 | i = history_offset; |
| 74 | reverse = (direction < 0); |
| 75 | |
| 76 | /* Take care of trivial cases first. */ |
| 77 | if (string == 0 || *string == '\0') |
| 78 | return (-1); |
| 79 | |
| 80 | if (!history_length || ((i == history_length) && !reverse)) |
| 81 | return (-1); |
| 82 | |
| 83 | if (reverse && (i == history_length)) |
| 84 | i--; |
| 85 | |
| 86 | #define NEXT_LINE() do { if (reverse) i--; else i++; } while (0) |
| 87 | |
| 88 | the_history = history_list (); |
| 89 | string_len = strlen (string); |
| 90 | while (1) |
| 91 | { |
| 92 | /* Search each line in the history list for STRING. */ |
| 93 | |
| 94 | /* At limit for direction? */ |
| 95 | if ((reverse && i < 0) || (!reverse && i == history_length)) |
| 96 | return (-1); |
| 97 | |
| 98 | line = the_history[i]->line; |
| 99 | line_index = strlen (line); |
| 100 | |
| 101 | /* If STRING is longer than line, no match. */ |
| 102 | if (string_len > line_index) |
| 103 | { |
| 104 | NEXT_LINE (); |
| 105 | continue; |
| 106 | } |
| 107 | |
| 108 | /* Handle anchored searches first. */ |
| 109 | if (anchored == ANCHORED_SEARCH) |
| 110 | { |
| 111 | if (STREQN (string, line, string_len)) |
| 112 | { |
| 113 | history_offset = i; |
| 114 | return (0); |
| 115 | } |
| 116 | |
| 117 | NEXT_LINE (); |
| 118 | continue; |
| 119 | } |
| 120 | |
| 121 | /* Do substring search. */ |
| 122 | if (reverse) |
| 123 | { |
| 124 | line_index -= string_len; |
| 125 | |
| 126 | while (line_index >= 0) |
| 127 | { |
| 128 | if (STREQN (string, line + line_index, string_len)) |
| 129 | { |
| 130 | history_offset = i; |
| 131 | return (line_index); |
| 132 | } |
| 133 | line_index--; |
| 134 | } |
| 135 | } |
| 136 | else |
| 137 | { |
| 138 | register int limit; |
| 139 | |
| 140 | limit = line_index - string_len + 1; |
| 141 | line_index = 0; |
| 142 | |
| 143 | while (line_index < limit) |
| 144 | { |
| 145 | if (STREQN (string, line + line_index, string_len)) |
| 146 | { |
| 147 | history_offset = i; |
| 148 | return (line_index); |
| 149 | } |
| 150 | line_index++; |
| 151 | } |
| 152 | } |
| 153 | NEXT_LINE (); |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | /* Do a non-anchored search for STRING through the history in DIRECTION. */ |
| 158 | int |
| 159 | history_search (string, direction) |
| 160 | const char *string; |
| 161 | int direction; |
| 162 | { |
| 163 | return (history_search_internal (string, direction, NON_ANCHORED_SEARCH)); |
| 164 | } |
| 165 | |
| 166 | /* Do an anchored search for string through the history in DIRECTION. */ |
| 167 | int |
| 168 | history_search_prefix (string, direction) |
| 169 | const char *string; |
| 170 | int direction; |
| 171 | { |
| 172 | return (history_search_internal (string, direction, ANCHORED_SEARCH)); |
| 173 | } |
| 174 | |
| 175 | /* Search for STRING in the history list. DIR is < 0 for searching |
| 176 | backwards. POS is an absolute index into the history list at |
| 177 | which point to begin searching. */ |
| 178 | int |
| 179 | history_search_pos (string, dir, pos) |
| 180 | const char *string; |
| 181 | int dir, pos; |
| 182 | { |
| 183 | int ret, old; |
| 184 | |
| 185 | old = where_history (); |
| 186 | history_set_pos (pos); |
| 187 | if (history_search (string, dir) == -1) |
| 188 | { |
| 189 | history_set_pos (old); |
| 190 | return (-1); |
| 191 | } |
| 192 | ret = where_history (); |
| 193 | history_set_pos (old); |
| 194 | return ret; |
| 195 | } |