From 14cd51f7793a9ce07bc435069f57269450141363 Mon Sep 17 00:00:00 2001 From: Stan Shebs Date: Fri, 16 Apr 1999 01:35:26 +0000 Subject: Initial revision --- readline/history.c | 388 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 388 insertions(+) create mode 100644 readline/history.c (limited to 'readline/history.c') diff --git a/readline/history.c b/readline/history.c new file mode 100644 index 00000000000..24c5a49c359 --- /dev/null +++ b/readline/history.c @@ -0,0 +1,388 @@ +/* History.c -- standalone history library */ + +/* 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. */ + +/* The goal is to make the implementation transparent, so that you + don't have to know what data types are used, just what functions + you can call. I think I have done that. */ +#define READLINE_LIBRARY + +#if defined (HAVE_CONFIG_H) +# include +#endif + +#include + +#if defined (HAVE_STDLIB_H) +# include +#else +# include "ansi_stdlib.h" +#endif /* HAVE_STDLIB_H */ + +#if defined (HAVE_UNISTD_H) +# ifdef _MINIX +# include +# endif +# include +#endif + +#if defined (HAVE_STRING_H) +# include +#else +# include +#endif /* !HAVE_STRING_H */ + +#include "history.h" +#include "histlib.h" + +extern char *xmalloc (), *xrealloc (); + +/* The number of slots to increase the_history by. */ +#define DEFAULT_HISTORY_GROW_SIZE 50 + +/* **************************************************************** */ +/* */ +/* History Functions */ +/* */ +/* **************************************************************** */ + +/* An array of HIST_ENTRY. This is where we store the history. */ +static HIST_ENTRY **the_history = (HIST_ENTRY **)NULL; + +/* Non-zero means that we have enforced a limit on the amount of + history that we save. */ +static int history_stifled; + +/* If HISTORY_STIFLED is non-zero, then this is the maximum number of + entries to remember. */ +int max_input_history; + +/* The current location of the interactive history pointer. Just makes + life easier for outside callers. */ +int history_offset; + +/* The number of strings currently stored in the history list. */ +int history_length; + +/* The current number of slots allocated to the input_history. */ +static int history_size; + +/* The logical `base' of the history array. It defaults to 1. */ +int history_base = 1; + +/* Return the current HISTORY_STATE of the history. */ +HISTORY_STATE * +history_get_history_state () +{ + HISTORY_STATE *state; + + state = (HISTORY_STATE *)xmalloc (sizeof (HISTORY_STATE)); + state->entries = the_history; + state->offset = history_offset; + state->length = history_length; + state->size = history_size; + state->flags = 0; + if (history_stifled) + state->flags |= HS_STIFLED; + + return (state); +} + +/* Set the state of the current history array to STATE. */ +void +history_set_history_state (state) + HISTORY_STATE *state; +{ + the_history = state->entries; + history_offset = state->offset; + history_length = state->length; + history_size = state->size; + if (state->flags & HS_STIFLED) + history_stifled = 1; +} + +/* Begin a session in which the history functions might be used. This + initializes interactive variables. */ +void +using_history () +{ + history_offset = history_length; +} + +/* Return the number of bytes that the primary history entries are using. + This just adds up the lengths of the_history->lines. */ +int +history_total_bytes () +{ + register int i, result; + + result = 0; + + for (i = 0; the_history && the_history[i]; i++) + result += strlen (the_history[i]->line); + + return (result); +} + +/* Returns the magic number which says what history element we are + looking at now. In this implementation, it returns history_offset. */ +int +where_history () +{ + return (history_offset); +} + +/* Make the current history item be the one at POS, an absolute index. + Returns zero if POS is out of range, else non-zero. */ +int +history_set_pos (pos) + int pos; +{ + if (pos > history_length || pos < 0 || !the_history) + return (0); + history_offset = pos; + return (1); +} + +/* Return the current history array. The caller has to be carefull, since this + is the actual array of data, and could be bashed or made corrupt easily. + The array is terminated with a NULL pointer. */ +HIST_ENTRY ** +history_list () +{ + return (the_history); +} + +/* Return the history entry at the current position, as determined by + history_offset. If there is no entry there, return a NULL pointer. */ +HIST_ENTRY * +current_history () +{ + return ((history_offset == history_length) || the_history == 0) + ? (HIST_ENTRY *)NULL + : the_history[history_offset]; +} + +/* Back up history_offset to the previous history entry, and return + a pointer to that entry. If there is no previous entry then return + a NULL pointer. */ +HIST_ENTRY * +previous_history () +{ + return history_offset ? the_history[--history_offset] : (HIST_ENTRY *)NULL; +} + +/* Move history_offset forward to the next history entry, and return + a pointer to that entry. If there is no next entry then return a + NULL pointer. */ +HIST_ENTRY * +next_history () +{ + return (history_offset == history_length) ? (HIST_ENTRY *)NULL : the_history[++history_offset]; +} + +/* Return the history entry which is logically at OFFSET in the history array. + OFFSET is relative to history_base. */ +HIST_ENTRY * +history_get (offset) + int offset; +{ + int local_index; + + local_index = offset - history_base; + return (local_index >= history_length || local_index < 0 || !the_history) + ? (HIST_ENTRY *)NULL + : the_history[local_index]; +} + +/* Place STRING at the end of the history list. The data field + is set to NULL. */ +void +add_history (string) + char *string; +{ + HIST_ENTRY *temp; + + if (history_stifled && (history_length == max_input_history)) + { + register int i; + + /* If the history is stifled, and history_length is zero, + and it equals max_input_history, we don't save items. */ + if (history_length == 0) + return; + + /* If there is something in the slot, then remove it. */ + if (the_history[0]) + { + free (the_history[0]->line); + free (the_history[0]); + } + + /* Copy the rest of the entries, moving down one slot. */ + for (i = 0; i < history_length; i++) + the_history[i] = the_history[i + 1]; + + history_base++; + } + else + { + if (history_size == 0) + { + history_size = DEFAULT_HISTORY_GROW_SIZE; + the_history = (HIST_ENTRY **)xmalloc (history_size * sizeof (HIST_ENTRY *)); + history_length = 1; + } + else + { + if (history_length == (history_size - 1)) + { + history_size += DEFAULT_HISTORY_GROW_SIZE; + the_history = (HIST_ENTRY **) + xrealloc (the_history, history_size * sizeof (HIST_ENTRY *)); + } + history_length++; + } + } + + temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); + temp->line = savestring (string); + temp->data = (char *)NULL; + + the_history[history_length] = (HIST_ENTRY *)NULL; + the_history[history_length - 1] = temp; +} + +/* Make the history entry at WHICH have LINE and DATA. This returns + the old entry so you can dispose of the data. In the case of an + invalid WHICH, a NULL pointer is returned. */ +HIST_ENTRY * +replace_history_entry (which, line, data) + int which; + char *line; + char *data; +{ + HIST_ENTRY *temp = (HIST_ENTRY *)xmalloc (sizeof (HIST_ENTRY)); + HIST_ENTRY *old_value; + + if (which >= history_length) + return ((HIST_ENTRY *)NULL); + + old_value = the_history[which]; + + temp->line = savestring (line); + temp->data = data; + the_history[which] = temp; + + return (old_value); +} + +/* Remove history element WHICH from the history. The removed + element is returned to you so you can free the line, data, + and containing structure. */ +HIST_ENTRY * +remove_history (which) + int which; +{ + HIST_ENTRY *return_value; + + if (which >= history_length || !history_length) + return_value = (HIST_ENTRY *)NULL; + else + { + register int i; + return_value = the_history[which]; + + for (i = which; i < history_length; i++) + the_history[i] = the_history[i + 1]; + + history_length--; + } + + return (return_value); +} + +/* Stifle the history list, remembering only MAX number of lines. */ +void +stifle_history (max) + int max; +{ + if (max < 0) + max = 0; + + if (history_length > max) + { + register int i, j; + + /* This loses because we cannot free the data. */ + for (i = 0, j = history_length - max; i < j; i++) + { + free (the_history[i]->line); + free (the_history[i]); + } + + history_base = i; + for (j = 0, i = history_length - max; j < max; i++, j++) + the_history[j] = the_history[i]; + the_history[j] = (HIST_ENTRY *)NULL; + history_length = j; + } + + history_stifled = 1; + max_input_history = max; +} + +/* Stop stifling the history. This returns the previous amount the + history was stifled by. The value is positive if the history was + stifled, negative if it wasn't. */ +int +unstifle_history () +{ + if (history_stifled) + { + history_stifled = 0; + return (-max_input_history); + } + + return (max_input_history); +} + +int +history_is_stifled () +{ + return (history_stifled); +} + +void +clear_history () +{ + register int i; + + /* This loses because we cannot free the data. */ + for (i = 0; i < history_length; i++) + { + free (the_history[i]->line); + free (the_history[i]); + the_history[i] = (HIST_ENTRY *)NULL; + } + + history_offset = history_length = 0; +} -- cgit v1.2.1