1 /* history.h -- the names of functions that you can call in history. */ 2 3 /* Copyright (C) 1989-2015 Free Software Foundation, Inc. 4 5 This file contains the GNU History Library (History), a set of 6 routines for managing the text of previously typed lines. 7 8 History 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 3 of the License, or 11 (at your option) any later version. 12 13 History is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with History. If not, see <http://www.gnu.org/licenses/>. 20 */ 21 22 #ifndef _HISTORY_H_ 23 #define _HISTORY_H_ 24 25 #ifdef __cplusplus 26 extern "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 <readline/rlstdc.h> 36 # include <readline/rltypedefs.h> 37 #endif 38 39 #ifdef __STDC__ 40 typedef void *histdata_t; 41 #else 42 typedef char *histdata_t; 43 #endif 44 45 /* The structure used to store a history entry. */ 46 typedef 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. */ 56 typedef 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. */ 71 extern void using_history PARAMS((void)); 72 73 /* Return the current HISTORY_STATE of the history. */ 74 extern HISTORY_STATE *history_get_history_state PARAMS((void)); 75 76 /* Set the state of the current history array to STATE. */ 77 extern 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. */ 83 extern void add_history PARAMS((const char *)); 84 85 /* Change the timestamp associated with the most recent history entry to 86 STRING. */ 87 extern void add_history_time PARAMS((const char *)); 88 89 /* Remove an entry from the history list. WHICH is the magic number that 90 tells us which element to delete. The elements are numbered from 0. */ 91 extern HIST_ENTRY *remove_history PARAMS((int)); 92 93 /* Remove a set of entries from the history list: FIRST to LAST, inclusive */ 94 extern HIST_ENTRY **remove_history_range PARAMS((int, int)); 95 96 /* Allocate a history entry consisting of STRING and TIMESTAMP and return 97 a pointer to it. */ 98 extern HIST_ENTRY *alloc_history_entry PARAMS((char *, char *)); 99 100 /* Copy the history entry H, but not the (opaque) data pointer */ 101 extern HIST_ENTRY *copy_history_entry PARAMS((HIST_ENTRY *)); 102 103 /* Free the history entry H and return any application-specific data 104 associated with it. */ 105 extern histdata_t free_history_entry PARAMS((HIST_ENTRY *)); 106 107 /* Make the history entry at WHICH have LINE and DATA. This returns 108 the old entry so you can dispose of the data. In the case of an 109 invalid WHICH, a NULL pointer is returned. */ 110 extern HIST_ENTRY *replace_history_entry PARAMS((int, const char *, histdata_t)); 111 112 /* Clear the history list and start over. */ 113 extern void clear_history PARAMS((void)); 114 115 /* Stifle the history list, remembering only MAX number of entries. */ 116 extern void stifle_history PARAMS((int)); 117 118 /* Stop stifling the history. This returns the previous amount the 119 history was stifled by. The value is positive if the history was 120 stifled, negative if it wasn't. */ 121 extern int unstifle_history PARAMS((void)); 122 123 /* Return 1 if the history is stifled, 0 if it is not. */ 124 extern int history_is_stifled PARAMS((void)); 125 126 /* Information about the history list. */ 127 128 /* Return a NULL terminated array of HIST_ENTRY which is the current input 129 history. Element 0 of this list is the beginning of time. If there 130 is no history, return NULL. */ 131 extern HIST_ENTRY **history_list PARAMS((void)); 132 133 /* Returns the number which says what history element we are now 134 looking at. */ 135 extern int where_history PARAMS((void)); 136 137 /* Return the history entry at the current position, as determined by 138 history_offset. If there is no entry there, return a NULL pointer. */ 139 extern HIST_ENTRY *current_history PARAMS((void)); 140 141 /* Return the history entry which is logically at OFFSET in the history 142 array. OFFSET is relative to history_base. */ 143 extern HIST_ENTRY *history_get PARAMS((int)); 144 145 /* Return the timestamp associated with the HIST_ENTRY * passed as an 146 argument */ 147 extern time_t history_get_time PARAMS((HIST_ENTRY *)); 148 149 /* Return the number of bytes that the primary history entries are using. 150 This just adds up the lengths of the_history->lines. */ 151 extern int history_total_bytes PARAMS((void)); 152 153 /* Moving around the history list. */ 154 155 /* Set the position in the history list to POS. */ 156 extern int history_set_pos PARAMS((int)); 157 158 /* Back up history_offset to the previous history entry, and return 159 a pointer to that entry. If there is no previous entry, return 160 a NULL pointer. */ 161 extern HIST_ENTRY *previous_history PARAMS((void)); 162 163 /* Move history_offset forward to the next item in the input_history, 164 and return the a pointer to that entry. If there is no next entry, 165 return a NULL pointer. */ 166 extern HIST_ENTRY *next_history PARAMS((void)); 167 168 /* Searching the history list. */ 169 170 /* Search the history for STRING, starting at history_offset. 171 If DIRECTION < 0, then the search is through previous entries, 172 else through subsequent. If the string is found, then 173 current_history () is the history entry, and the value of this function 174 is the offset in the line of that history entry that the string was 175 found in. Otherwise, nothing is changed, and a -1 is returned. */ 176 extern int history_search PARAMS((const char *, int)); 177 178 /* Search the history for STRING, starting at history_offset. 179 The search is anchored: matching lines must begin with string. 180 DIRECTION is as in history_search(). */ 181 extern int history_search_prefix PARAMS((const char *, int)); 182 183 /* Search for STRING in the history list, starting at POS, an 184 absolute index into the list. DIR, if negative, says to search 185 backwards from POS, else forwards. 186 Returns the absolute index of the history element where STRING 187 was found, or -1 otherwise. */ 188 extern int history_search_pos PARAMS((const char *, int, int)); 189 190 /* Managing the history file. */ 191 192 /* Add the contents of FILENAME to the history list, a line at a time. 193 If FILENAME is NULL, then read from ~/.history. Returns 0 if 194 successful, or errno if not. */ 195 extern int read_history PARAMS((const char *)); 196 197 /* Read a range of lines from FILENAME, adding them to the history list. 198 Start reading at the FROM'th line and end at the TO'th. If FROM 199 is zero, start at the beginning. If TO is less than FROM, read 200 until the end of the file. If FILENAME is NULL, then read from 201 ~/.history. Returns 0 if successful, or errno if not. */ 202 extern int read_history_range PARAMS((const char *, int, int)); 203 204 /* Write the current history to FILENAME. If FILENAME is NULL, 205 then write the history list to ~/.history. Values returned 206 are as in read_history (). */ 207 extern int write_history PARAMS((const char *)); 208 209 /* Append NELEMENT entries to FILENAME. The entries appended are from 210 the end of the list minus NELEMENTs up to the end of the list. */ 211 extern int append_history PARAMS((int, const char *)); 212 213 /* Truncate the history file, leaving only the last NLINES lines. */ 214 extern int history_truncate_file PARAMS((const char *, int)); 215 216 /* History expansion. */ 217 218 /* Expand the string STRING, placing the result into OUTPUT, a pointer 219 to a string. Returns: 220 221 0) If no expansions took place (or, if the only change in 222 the text was the de-slashifying of the history expansion 223 character) 224 1) If expansions did take place 225 -1) If there was an error in expansion. 226 2) If the returned line should just be printed. 227 228 If an error occurred in expansion, then OUTPUT contains a descriptive 229 error message. */ 230 extern int history_expand PARAMS((char *, char **)); 231 232 /* Extract a string segment consisting of the FIRST through LAST 233 arguments present in STRING. Arguments are broken up as in 234 the shell. */ 235 extern char *history_arg_extract PARAMS((int, int, const char *)); 236 237 /* Return the text of the history event beginning at the current 238 offset into STRING. Pass STRING with *INDEX equal to the 239 history_expansion_char that begins this specification. 240 DELIMITING_QUOTE is a character that is allowed to end the string 241 specification for what to search for in addition to the normal 242 characters `:', ` ', `\t', `\n', and sometimes `?'. */ 243 extern char *get_history_event PARAMS((const char *, int *, int)); 244 245 /* Return an array of tokens, much as the shell might. The tokens are 246 parsed out of STRING. */ 247 extern char **history_tokenize PARAMS((const char *)); 248 249 /* Exported history variables. */ 250 extern int history_base; 251 extern int history_length; 252 extern int history_max_entries; 253 extern int history_offset; 254 255 extern int history_lines_read_from_file; 256 extern int history_lines_written_to_file; 257 258 extern char history_expansion_char; 259 extern char history_subst_char; 260 extern char *history_word_delimiters; 261 extern char history_comment_char; 262 extern char *history_no_expand_chars; 263 extern char *history_search_delimiter_chars; 264 265 extern int history_quotes_inhibit_expansion; 266 extern int history_quoting_state; 267 268 extern int history_write_timestamps; 269 270 /* These two are undocumented; the second is reserved for future use */ 271 extern int history_multiline_entries; 272 extern int history_file_version; 273 274 /* Backwards compatibility */ 275 extern int max_input_history; 276 277 /* If set, this function is called to decide whether or not a particular 278 history expansion should be treated as a special case for the calling 279 application and not expanded. */ 280 extern rl_linebuf_func_t *history_inhibit_expansion_function; 281 282 #ifdef __cplusplus 283 } 284 #endif 285 286 #endif /* !_HISTORY_H_ */ 287