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726f6388 JA |
1 | /* History.c -- standalone history library */ |
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 | |
bb70624e | 10 | the Free Software Foundation; either version 2, or (at your option) |
726f6388 JA |
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, | |
bb70624e | 21 | 59 Temple Place, Suite 330, Boston, MA 02111 USA. */ |
726f6388 JA |
22 | |
23 | /* The goal is to make the implementation transparent, so that you | |
24 | don't have to know what data types are used, just what functions | |
25 | you can call. I think I have done that. */ | |
26 | #define READLINE_LIBRARY | |
27 | ||
ccc6cda3 JA |
28 | #if defined (HAVE_CONFIG_H) |
29 | # include <config.h> | |
30 | #endif | |
31 | ||
726f6388 | 32 | #include <stdio.h> |
ccc6cda3 | 33 | |
726f6388 JA |
34 | #if defined (HAVE_STDLIB_H) |
35 | # include <stdlib.h> | |
36 | #else | |
37 | # include "ansi_stdlib.h" | |
38 | #endif /* HAVE_STDLIB_H */ | |
ccc6cda3 | 39 | |
726f6388 | 40 | #if defined (HAVE_UNISTD_H) |
cce855bc JA |
41 | # ifdef _MINIX |
42 | # include <sys/types.h> | |
43 | # endif | |
726f6388 JA |
44 | # include <unistd.h> |
45 | #endif | |
ccc6cda3 | 46 | |
726f6388 JA |
47 | #if defined (HAVE_STRING_H) |
48 | # include <string.h> | |
49 | #else | |
50 | # include <strings.h> | |
51 | #endif /* !HAVE_STRING_H */ | |
726f6388 | 52 | |
726f6388 | 53 | #include "history.h" |
ccc6cda3 | 54 | #include "histlib.h" |
726f6388 | 55 | |
bb70624e | 56 | #include "xmalloc.h" |
726f6388 | 57 | |
ccc6cda3 JA |
58 | /* The number of slots to increase the_history by. */ |
59 | #define DEFAULT_HISTORY_GROW_SIZE 50 | |
726f6388 JA |
60 | |
61 | /* **************************************************************** */ | |
62 | /* */ | |
63 | /* History Functions */ | |
64 | /* */ | |
65 | /* **************************************************************** */ | |
66 | ||
67 | /* An array of HIST_ENTRY. This is where we store the history. */ | |
68 | static HIST_ENTRY **the_history = (HIST_ENTRY **)NULL; | |
69 | ||
70 | /* Non-zero means that we have enforced a limit on the amount of | |
71 | history that we save. */ | |
ccc6cda3 | 72 | static int history_stifled; |
726f6388 JA |
73 | |
74 | /* If HISTORY_STIFLED is non-zero, then this is the maximum number of | |
75 | entries to remember. */ | |
28ef6c31 JA |
76 | int history_max_entries; |
77 | int max_input_history; /* backwards compatibility */ | |
726f6388 JA |
78 | |
79 | /* The current location of the interactive history pointer. Just makes | |
80 | life easier for outside callers. */ | |
ccc6cda3 | 81 | int history_offset; |
726f6388 | 82 | |
ccc6cda3 JA |
83 | /* The number of strings currently stored in the history list. */ |
84 | int history_length; | |
726f6388 JA |
85 | |
86 | /* The current number of slots allocated to the input_history. */ | |
ccc6cda3 | 87 | static int history_size; |
726f6388 JA |
88 | |
89 | /* The logical `base' of the history array. It defaults to 1. */ | |
90 | int history_base = 1; | |
91 | ||
92 | /* Return the current HISTORY_STATE of the history. */ | |
93 | HISTORY_STATE * | |
94 | history_get_history_state () | |
95 | { | |
96 | HISTORY_STATE *state; | |
97 | ||
98 | state = (HISTORY_STATE *)xmalloc (sizeof (HISTORY_STATE)); | |
99 | state->entries = the_history; | |
100 | state->offset = history_offset; | |
101 | state->length = history_length; | |
102 | state->size = history_size; | |
103 | state->flags = 0; | |
104 | if (history_stifled) | |
105 | state->flags |= HS_STIFLED; | |
106 | ||
107 | return (state); | |
108 | } | |
109 | ||
110 | /* Set the state of the current history array to STATE. */ | |
111 | void | |
112 | history_set_history_state (state) | |
113 | HISTORY_STATE *state; | |
114 | { | |
115 | the_history = state->entries; | |
116 | history_offset = state->offset; | |
117 | history_length = state->length; | |
118 | history_size = state->size; | |
119 | if (state->flags & HS_STIFLED) | |
120 | history_stifled = 1; | |
121 | } | |
122 | ||
123 | /* Begin a session in which the history functions might be used. This | |
124 | initializes interactive variables. */ | |
125 | void | |
126 | using_history () | |
127 | { | |
128 | history_offset = history_length; | |
129 | } | |
130 | ||
131 | /* Return the number of bytes that the primary history entries are using. | |
132 | This just adds up the lengths of the_history->lines. */ | |
133 | int | |
134 | history_total_bytes () | |
135 | { | |
136 | register int i, result; | |
137 | ||
28ef6c31 | 138 | for (i = result = 0; the_history && the_history[i]; i++) |
726f6388 JA |
139 | result += strlen (the_history[i]->line); |
140 | ||
141 | return (result); | |
142 | } | |
143 | ||
ccc6cda3 JA |
144 | /* Returns the magic number which says what history element we are |
145 | looking at now. In this implementation, it returns history_offset. */ | |
146 | int | |
147 | where_history () | |
148 | { | |
149 | return (history_offset); | |
150 | } | |
151 | ||
152 | /* Make the current history item be the one at POS, an absolute index. | |
153 | Returns zero if POS is out of range, else non-zero. */ | |
154 | int | |
155 | history_set_pos (pos) | |
156 | int pos; | |
157 | { | |
158 | if (pos > history_length || pos < 0 || !the_history) | |
159 | return (0); | |
160 | history_offset = pos; | |
161 | return (1); | |
162 | } | |
163 | ||
164 | /* Return the current history array. The caller has to be carefull, since this | |
165 | is the actual array of data, and could be bashed or made corrupt easily. | |
166 | The array is terminated with a NULL pointer. */ | |
167 | HIST_ENTRY ** | |
168 | history_list () | |
169 | { | |
170 | return (the_history); | |
171 | } | |
172 | ||
173 | /* Return the history entry at the current position, as determined by | |
174 | history_offset. If there is no entry there, return a NULL pointer. */ | |
175 | HIST_ENTRY * | |
176 | current_history () | |
177 | { | |
178 | return ((history_offset == history_length) || the_history == 0) | |
179 | ? (HIST_ENTRY *)NULL | |
180 | : the_history[history_offset]; | |
181 | } | |
182 | ||
183 | /* Back up history_offset to the previous history entry, and return | |
184 | a pointer to that entry. If there is no previous entry then return | |
185 | a NULL pointer. */ | |
186 | HIST_ENTRY * | |
187 | previous_history () | |
188 | { | |
189 | return history_offset ? the_history[--history_offset] : (HIST_ENTRY *)NULL; | |
190 | } | |
191 | ||
192 | /* Move history_offset forward to the next history entry, and return | |
193 | a pointer to that entry. If there is no next entry then return a | |
194 | NULL pointer. */ | |
195 | HIST_ENTRY * | |
196 | next_history () | |
197 | { | |
198 | return (history_offset == history_length) ? (HIST_ENTRY *)NULL : the_history[++history_offset]; | |
199 | } | |
200 | ||
201 | /* Return the history entry which is logically at OFFSET in the history array. | |
202 | OFFSET is relative to history_base. */ | |
203 | HIST_ENTRY * | |
204 | history_get (offset) | |
205 | int offset; | |
206 | { | |
207 | int local_index; | |
208 | ||
209 | local_index = offset - history_base; | |
210 | return (local_index >= history_length || local_index < 0 || !the_history) | |
211 | ? (HIST_ENTRY *)NULL | |
212 | : the_history[local_index]; | |
213 | } | |
214 | ||
726f6388 JA |
215 | /* Place STRING at the end of the history list. The data field |
216 | is set to NULL. */ | |
217 | void | |
218 | add_history (string) | |
28ef6c31 | 219 | const char *string; |
726f6388 JA |
220 | { |
221 | HIST_ENTRY *temp; | |
222 | ||
28ef6c31 | 223 | if (history_stifled && (history_length == history_max_entries)) |
726f6388 JA |
224 | { |
225 | register int i; | |
226 | ||
227 | /* If the history is stifled, and history_length is zero, | |
28ef6c31 | 228 | and it equals history_max_entries, we don't save items. */ |
726f6388 JA |
229 | if (history_length == 0) |
230 | return; | |
231 | ||
232 | /* If there is something in the slot, then remove it. */ | |
233 | if (the_history[0]) | |
234 | { | |
235 | free (the_history[0]->line); | |
236 | free (the_history[0]); | |
237 | } | |
238 | ||
239 | /* Copy the rest of the entries, moving down one slot. */ | |
240 | for (i = 0; i < history_length; i++) | |
241 | the_history[i] = the_history[i + 1]; | |
242 | ||
243 | history_base++; | |
726f6388 JA |
244 | } |
245 | else | |
246 | { | |
ccc6cda3 | 247 | if (history_size == 0) |
726f6388 JA |
248 | { |
249 | history_size = DEFAULT_HISTORY_GROW_SIZE; | |
250 | the_history = (HIST_ENTRY **)xmalloc (history_size * sizeof (HIST_ENTRY *)); | |
251 | history_length = 1; | |
726f6388 JA |
252 | } |
253 | else | |
254 | { | |
255 | if (history_length == (history_size - 1)) | |
256 | { | |
257 | history_size += DEFAULT_HISTORY_GROW_SIZE; | |
258 | the_history = (HIST_ENTRY **) | |
259 | xrealloc (the_history, history_size * sizeof (HIST_ENTRY *)); | |
260 | } | |
261 | history_length++; | |
262 | } | |
263 | } | |
264 | ||
265 | temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); | |
266 | temp->line = savestring (string); | |
267 | temp->data = (char *)NULL; | |
268 | ||
269 | the_history[history_length] = (HIST_ENTRY *)NULL; | |
270 | the_history[history_length - 1] = temp; | |
271 | } | |
272 | ||
273 | /* Make the history entry at WHICH have LINE and DATA. This returns | |
274 | the old entry so you can dispose of the data. In the case of an | |
275 | invalid WHICH, a NULL pointer is returned. */ | |
276 | HIST_ENTRY * | |
277 | replace_history_entry (which, line, data) | |
278 | int which; | |
28ef6c31 | 279 | const char *line; |
b72432fd | 280 | histdata_t data; |
726f6388 | 281 | { |
28ef6c31 | 282 | HIST_ENTRY *temp, *old_value; |
726f6388 JA |
283 | |
284 | if (which >= history_length) | |
285 | return ((HIST_ENTRY *)NULL); | |
286 | ||
28ef6c31 | 287 | temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); |
726f6388 JA |
288 | old_value = the_history[which]; |
289 | ||
290 | temp->line = savestring (line); | |
291 | temp->data = data; | |
292 | the_history[which] = temp; | |
293 | ||
294 | return (old_value); | |
295 | } | |
296 | ||
726f6388 JA |
297 | /* Remove history element WHICH from the history. The removed |
298 | element is returned to you so you can free the line, data, | |
299 | and containing structure. */ | |
300 | HIST_ENTRY * | |
301 | remove_history (which) | |
302 | int which; | |
303 | { | |
304 | HIST_ENTRY *return_value; | |
28ef6c31 | 305 | register int i; |
726f6388 JA |
306 | |
307 | if (which >= history_length || !history_length) | |
308 | return_value = (HIST_ENTRY *)NULL; | |
309 | else | |
310 | { | |
726f6388 JA |
311 | return_value = the_history[which]; |
312 | ||
313 | for (i = which; i < history_length; i++) | |
314 | the_history[i] = the_history[i + 1]; | |
315 | ||
316 | history_length--; | |
317 | } | |
318 | ||
319 | return (return_value); | |
320 | } | |
321 | ||
322 | /* Stifle the history list, remembering only MAX number of lines. */ | |
323 | void | |
324 | stifle_history (max) | |
325 | int max; | |
326 | { | |
28ef6c31 JA |
327 | register int i, j; |
328 | ||
726f6388 JA |
329 | if (max < 0) |
330 | max = 0; | |
331 | ||
332 | if (history_length > max) | |
333 | { | |
726f6388 | 334 | /* This loses because we cannot free the data. */ |
ccc6cda3 | 335 | for (i = 0, j = history_length - max; i < j; i++) |
726f6388 JA |
336 | { |
337 | free (the_history[i]->line); | |
338 | free (the_history[i]); | |
339 | } | |
340 | ||
341 | history_base = i; | |
342 | for (j = 0, i = history_length - max; j < max; i++, j++) | |
343 | the_history[j] = the_history[i]; | |
344 | the_history[j] = (HIST_ENTRY *)NULL; | |
345 | history_length = j; | |
346 | } | |
347 | ||
348 | history_stifled = 1; | |
28ef6c31 | 349 | max_input_history = history_max_entries = max; |
726f6388 JA |
350 | } |
351 | ||
ccc6cda3 JA |
352 | /* Stop stifling the history. This returns the previous amount the |
353 | history was stifled by. The value is positive if the history was | |
354 | stifled, negative if it wasn't. */ | |
726f6388 JA |
355 | int |
356 | unstifle_history () | |
357 | { | |
726f6388 JA |
358 | if (history_stifled) |
359 | { | |
726f6388 | 360 | history_stifled = 0; |
28ef6c31 | 361 | return (-history_max_entries); |
726f6388 JA |
362 | } |
363 | ||
28ef6c31 | 364 | return (history_max_entries); |
726f6388 JA |
365 | } |
366 | ||
367 | int | |
368 | history_is_stifled () | |
369 | { | |
370 | return (history_stifled); | |
371 | } | |
372 | ||
ccc6cda3 JA |
373 | void |
374 | clear_history () | |
726f6388 JA |
375 | { |
376 | register int i; | |
726f6388 | 377 | |
ccc6cda3 JA |
378 | /* This loses because we cannot free the data. */ |
379 | for (i = 0; i < history_length; i++) | |
726f6388 | 380 | { |
ccc6cda3 JA |
381 | free (the_history[i]->line); |
382 | free (the_history[i]); | |
383 | the_history[i] = (HIST_ENTRY *)NULL; | |
726f6388 JA |
384 | } |
385 | ||
ccc6cda3 | 386 | history_offset = history_length = 0; |
726f6388 | 387 | } |