1/* history.h -- the names of functions that you can call in history. */
2/* Copyright (C) 1989-2003 Free Software Foundation, Inc.
3
4 This file contains the GNU History Library (the Library), a set of
5 routines for managing the text of previously typed lines.
6
7 The Library is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 The Library is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 General Public License for more details.
16
17 The GNU General Public License is often shipped with GNU software, and
18 is generally kept in a file called COPYING or LICENSE. If you do not
19 have a copy of the license, write to the Free Software Foundation,
20 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
21
22#ifndef _HISTORY_H_
23#define _HISTORY_H_
24
25#ifdef __cplusplus
26extern "C" {
27#endif
28
29#include <time.h> /* XXX - for history timestamp code */
30
31#if defined READLINE_LIBRARY
32# include "rlstdc.h"
33# include "rltypedefs.h"
34#else
35# include <rlstdc.h>
36# include <rltypedefs.h>
37#endif
38
39#ifdef __STDC__
40typedef void *histdata_t;
41#else
42typedef char *histdata_t;
43#endif
44
45/* The structure used to store a history entry. */
46typedef struct _hist_entry {
47 char *line;
48 char *timestamp; /* char * rather than time_t for read/write */
49 histdata_t data;
50} HIST_ENTRY;
51
52/* Size of the history-library-managed space in history entry HS. */
53#define HISTENT_BYTES(hs) (strlen ((hs)->line) + strlen ((hs)->timestamp))
54
55/* A structure used to pass the current state of the history stuff around. */
56typedef struct _hist_state {
57 HIST_ENTRY **entries; /* Pointer to the entries themselves. */
58 int offset; /* The location pointer within this array. */
59 int length; /* Number of elements within this array. */
60 int size; /* Number of slots allocated to this array. */
61 int flags;
62} HISTORY_STATE;
63
64/* Flag values for the `flags' member of HISTORY_STATE. */
65#define HS_STIFLED 0x01
66
67/* Initialization and state management. */
68
69/* Begin a session in which the history functions might be used. This
70 just initializes the interactive variables. */
71extern void using_history PARAMS((void));
72
73/* Return the current HISTORY_STATE of the history. */
74extern HISTORY_STATE *history_get_history_state PARAMS((void));
75
76/* Set the state of the current history array to STATE. */
77extern void history_set_history_state PARAMS((HISTORY_STATE *));
78
79/* Manage the history list. */
80
81/* Place STRING at the end of the history list.
82 The associated data field (if any) is set to NULL. */
83extern void add_history PARAMS((const char *));
84
85/* Change the timestamp associated with the most recent history entry to
86 STRING. */
87extern void add_history_time PARAMS((const char *));
88
89/* A reasonably useless function, only here for completeness. WHICH
90 is the magic number that tells us which element to delete. The
91 elements are numbered from 0. */
92extern HIST_ENTRY *remove_history PARAMS((int));
93
94/* Free the history entry H and return any application-specific data
95 associated with it. */
96extern histdata_t free_history_entry PARAMS((HIST_ENTRY *));
97
98/* Make the history entry at WHICH have LINE and DATA. This returns
99 the old entry so you can dispose of the data. In the case of an
100 invalid WHICH, a NULL pointer is returned. */
101extern HIST_ENTRY *replace_history_entry PARAMS((int, const char *, histdata_t));
102
103/* Clear the history list and start over. */
104extern void clear_history PARAMS((void));
105
106/* Stifle the history list, remembering only MAX number of entries. */
107extern void stifle_history PARAMS((int));
108
109/* Stop stifling the history. This returns the previous amount the
110 history was stifled by. The value is positive if the history was
111 stifled, negative if it wasn't. */
112extern int unstifle_history PARAMS((void));
113
114/* Return 1 if the history is stifled, 0 if it is not. */
115extern int history_is_stifled PARAMS((void));
116
117/* Information about the history list. */
118
119/* Return a NULL terminated array of HIST_ENTRY which is the current input
120 history. Element 0 of this list is the beginning of time. If there
121 is no history, return NULL. */
122extern HIST_ENTRY **history_list PARAMS((void));
123
124/* Returns the number which says what history element we are now
125 looking at. */
126extern int where_history PARAMS((void));
127
128/* Return the history entry at the current position, as determined by
129 history_offset. If there is no entry there, return a NULL pointer. */
130extern HIST_ENTRY *current_history PARAMS((void));
131
132/* Return the history entry which is logically at OFFSET in the history
133 array. OFFSET is relative to history_base. */
134extern HIST_ENTRY *history_get PARAMS((int));
135
136/* Return the timestamp associated with the HIST_ENTRY * passed as an
137 argument */
138extern time_t history_get_time PARAMS((HIST_ENTRY *));
139
140/* Return the number of bytes that the primary history entries are using.
141 This just adds up the lengths of the_history->lines. */
142extern int history_total_bytes PARAMS((void));
143
144/* Moving around the history list. */
145
146/* Set the position in the history list to POS. */
147extern int history_set_pos PARAMS((int));
148
149/* Back up history_offset to the previous history entry, and return
150 a pointer to that entry. If there is no previous entry, return
151 a NULL pointer. */
152extern HIST_ENTRY *previous_history PARAMS((void));
153
154/* Move history_offset forward to the next item in the input_history,
155 and return the a pointer to that entry. If there is no next entry,
156 return a NULL pointer. */
157extern HIST_ENTRY *next_history PARAMS((void));
158
159/* Searching the history list. */
160
161/* Search the history for STRING, starting at history_offset.
162 If DIRECTION < 0, then the search is through previous entries,
163 else through subsequent. If the string is found, then
164 current_history () is the history entry, and the value of this function
165 is the offset in the line of that history entry that the string was
166 found in. Otherwise, nothing is changed, and a -1 is returned. */
167extern int history_search PARAMS((const char *, int));
168
169/* Search the history for STRING, starting at history_offset.
170 The search is anchored: matching lines must begin with string.
171 DIRECTION is as in history_search(). */
172extern int history_search_prefix PARAMS((const char *, int));
173
174/* Search for STRING in the history list, starting at POS, an
175 absolute index into the list. DIR, if negative, says to search
176 backwards from POS, else forwards.
177 Returns the absolute index of the history element where STRING
178 was found, or -1 otherwise. */
179extern int history_search_pos PARAMS((const char *, int, int));
180
181/* Managing the history file. */
182
183/* Add the contents of FILENAME to the history list, a line at a time.
184 If FILENAME is NULL, then read from ~/.history. Returns 0 if
185 successful, or errno if not. */
186extern int read_history PARAMS((const char *));
187
188/* Read a range of lines from FILENAME, adding them to the history list.
189 Start reading at the FROM'th line and end at the TO'th. If FROM
190 is zero, start at the beginning. If TO is less than FROM, read
191 until the end of the file. If FILENAME is NULL, then read from
192 ~/.history. Returns 0 if successful, or errno if not. */
193extern int read_history_range PARAMS((const char *, int, int));
194
195/* Write the current history to FILENAME. If FILENAME is NULL,
196 then write the history list to ~/.history. Values returned
197 are as in read_history (). */
198extern int write_history PARAMS((const char *));
199
200/* Append NELEMENT entries to FILENAME. The entries appended are from
201 the end of the list minus NELEMENTs up to the end of the list. */
202extern int append_history PARAMS((int, const char *));
203
204/* Truncate the history file, leaving only the last NLINES lines. */
205extern int history_truncate_file PARAMS((const char *, int));
206
207/* History expansion. */
208
209/* Expand the string STRING, placing the result into OUTPUT, a pointer
210 to a string. Returns:
211
212 0) If no expansions took place (or, if the only change in
213 the text was the de-slashifying of the history expansion
214 character)
215 1) If expansions did take place
216 -1) If there was an error in expansion.
217 2) If the returned line should just be printed.
218
219 If an error ocurred in expansion, then OUTPUT contains a descriptive
220 error message. */
221extern int history_expand PARAMS((char *, char **));
222
223/* Extract a string segment consisting of the FIRST through LAST
224 arguments present in STRING. Arguments are broken up as in
225 the shell. */
226extern char *history_arg_extract PARAMS((int, int, const char *));
227
228/* Return the text of the history event beginning at the current
229 offset into STRING. Pass STRING with *INDEX equal to the
230 history_expansion_char that begins this specification.
231 DELIMITING_QUOTE is a character that is allowed to end the string
232 specification for what to search for in addition to the normal
233 characters `:', ` ', `\t', `\n', and sometimes `?'. */
234extern char *get_history_event PARAMS((const char *, int *, int));
235
236/* Return an array of tokens, much as the shell might. The tokens are
237 parsed out of STRING. */
238extern char **history_tokenize PARAMS((const char *));
239
240/* Exported history variables. */
241extern int history_base;
242extern int history_length;
243extern int history_max_entries;
244extern char history_expansion_char;
245extern char history_subst_char;
246extern const char *history_word_delimiters;
247extern char history_comment_char;
248extern const char *history_no_expand_chars;
249extern char *history_search_delimiter_chars;
250extern int history_quotes_inhibit_expansion;
251
252extern int history_write_timestamps;
253
254/* Backwards compatibility */
255extern int max_input_history;
256
257/* If set, this function is called to decide whether or not a particular
258 history expansion should be treated as a special case for the calling
259 application and not expanded. */
260extern rl_linebuf_func_t *history_inhibit_expansion_function;
261
262#ifdef __cplusplus
263}
264#endif
265
266#endif /* !_HISTORY_H_ */
267