xref: /openbsd/lib/libedit/readline.c (revision d89ec533)
1 /*	$OpenBSD: readline.c,v 1.29 2019/08/14 08:31:00 asou Exp $	*/
2 /*	$NetBSD: readline.c,v 1.91 2010/08/28 15:44:59 christos Exp $	*/
3 
4 /*-
5  * Copyright (c) 1997 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jaromir Dolecek.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include "config.h"
34 
35 #include <sys/types.h>
36 #include <sys/stat.h>
37 #include <ctype.h>
38 #include <dirent.h>
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <limits.h>
42 #include <pwd.h>
43 #include <setjmp.h>
44 #include <stdint.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #ifdef HAVE_VIS_H
50 #include <vis.h>
51 #else
52 #include "np/vis.h"
53 #endif
54 #include "readline/readline.h"
55 #include "el.h"
56 #include "fcns.h"
57 #include "filecomplete.h"
58 
59 void rl_prep_terminal(int);
60 void rl_deprep_terminal(void);
61 
62 /* for rl_complete() */
63 #define TAB		'\r'
64 
65 /* see comment at the #ifdef for sense of this */
66 /* #define GDB_411_HACK */
67 
68 /* readline compatibility stuff - look at readline sources/documentation */
69 /* to see what these variables mean */
70 const char *rl_library_version = "EditLine wrapper";
71 int rl_readline_version = RL_READLINE_VERSION;
72 static char empty[] = { '\0' };
73 static char expand_chars[] = { ' ', '\t', '\n', '=', '(', '\0' };
74 static char break_chars[] = { ' ', '\t', '\n', '"', '\\', '\'', '`', '@', '$',
75     '>', '<', '=', ';', '|', '&', '{', '(', '\0' };
76 char *rl_readline_name = empty;
77 FILE *rl_instream = NULL;
78 FILE *rl_outstream = NULL;
79 int rl_point = 0;
80 int rl_end = 0;
81 char *rl_line_buffer = NULL;
82 VCPFunction *rl_linefunc = NULL;
83 int rl_done = 0;
84 VFunction *rl_event_hook = NULL;
85 KEYMAP_ENTRY_ARRAY emacs_standard_keymap,
86     emacs_meta_keymap,
87     emacs_ctlx_keymap;
88 
89 int history_base = 1;		/* probably never subject to change */
90 int history_length = 0;
91 int max_input_history = 0;
92 char history_expansion_char = '!';
93 char history_subst_char = '^';
94 char *history_no_expand_chars = expand_chars;
95 Function *history_inhibit_expansion_function = NULL;
96 char *history_arg_extract(int start, int end, const char *str);
97 
98 int rl_inhibit_completion = 0;
99 int rl_attempted_completion_over = 0;
100 char *rl_basic_word_break_characters = break_chars;
101 char *rl_completer_word_break_characters = NULL;
102 char *rl_completer_quote_characters = NULL;
103 Function *rl_completion_entry_function = NULL;
104 CPPFunction *rl_attempted_completion_function = NULL;
105 Function *rl_pre_input_hook = NULL;
106 Function *rl_startup1_hook = NULL;
107 int (*rl_getc_function)(FILE *) = NULL;
108 char *rl_terminal_name = NULL;
109 int rl_already_prompted = 0;
110 int rl_filename_completion_desired = 0;
111 int rl_ignore_completion_duplicates = 0;
112 int rl_catch_signals = 1;
113 int readline_echoing_p = 1;
114 int _rl_print_completions_horizontally = 0;
115 VFunction *rl_redisplay_function = NULL;
116 Function *rl_startup_hook = NULL;
117 VFunction *rl_completion_display_matches_hook = NULL;
118 VFunction *rl_prep_term_function = (VFunction *)rl_prep_terminal;
119 VFunction *rl_deprep_term_function = (VFunction *)rl_deprep_terminal;
120 KEYMAP_ENTRY_ARRAY emacs_meta_keymap;
121 
122 /*
123  * The current prompt string.
124  */
125 char *rl_prompt = NULL;
126 /*
127  * This is set to character indicating type of completion being done by
128  * rl_complete_internal(); this is available for application completion
129  * functions.
130  */
131 int rl_completion_type = 0;
132 
133 /*
134  * If more than this number of items results from query for possible
135  * completions, we ask user if they are sure to really display the list.
136  */
137 int rl_completion_query_items = 100;
138 
139 /*
140  * List of characters which are word break characters, but should be left
141  * in the parsed text when it is passed to the completion function.
142  * Shell uses this to help determine what kind of completing to do.
143  */
144 char *rl_special_prefixes = NULL;
145 
146 /*
147  * This is the character appended to the completed words if at the end of
148  * the line. Default is ' ' (a space).
149  */
150 int rl_completion_append_character = ' ';
151 
152 /*
153  * When the history cursor is on the newest element and next_history()
154  * is called, GNU readline moves the cursor beyond the newest element.
155  * The editline library does not provide data structures to express
156  * that state, so we need a local flag.
157  */
158 static int current_history_valid = 1;
159 
160 /* stuff below is used internally by libedit for readline emulation */
161 
162 static History *h = NULL;
163 static EditLine *e = NULL;
164 static Function *map[256];
165 static jmp_buf topbuf;
166 
167 /* internal functions */
168 static unsigned char	 _el_rl_complete(EditLine *, int);
169 static unsigned char	 _el_rl_tstp(EditLine *, int);
170 static char		*_get_prompt(EditLine *);
171 static int		 _getc_function(EditLine *, wchar_t *);
172 static HIST_ENTRY	*_move_history(int);
173 static int		 _history_expand_command(const char *, size_t, size_t,
174     char **);
175 static char		*_rl_compat_sub(const char *, const char *,
176     const char *, int);
177 static int		 _rl_event_read_char(EditLine *, wchar_t *);
178 static void		 _rl_update_pos(void);
179 
180 
181 /* ARGSUSED */
182 static char *
183 _get_prompt(EditLine *el __attribute__((__unused__)))
184 {
185 	rl_already_prompted = 1;
186 	return rl_prompt;
187 }
188 
189 
190 /*
191  * generic function for moving around history
192  */
193 static HIST_ENTRY *
194 _move_history(int op)
195 {
196 	HistEvent ev;
197 	static HIST_ENTRY rl_he;
198 
199 	if (history(h, &ev, op) != 0)
200 		return NULL;
201 
202 	rl_he.line = ev.str;
203 	rl_he.data = NULL;
204 
205 	return &rl_he;
206 }
207 
208 
209 /*
210  * read one key from user defined input function
211  */
212 static int
213 /*ARGSUSED*/
214 _getc_function(EditLine *el __attribute__((__unused__)), wchar_t *c)
215 {
216 	int i;
217 
218 	i = (*rl_getc_function)(NULL);
219 	if (i == -1)
220 		return 0;
221 	*c = (wchar_t)i;
222 	return 1;
223 }
224 
225 static void
226 _resize_fun(EditLine *el, void *a)
227 {
228 	const LineInfo *li;
229 	char **ap = a;
230 
231 	li = el_line(el);
232 	/* a cheesy way to get rid of const cast. */
233 	*ap = memchr(li->buffer, *li->buffer, 1);
234 }
235 
236 static const char _dothistory[] = "/.history";
237 
238 static const char *
239 _default_history_file(void)
240 {
241 	struct passwd *p;
242 	static char path[PATH_MAX];
243 
244 	if (*path)
245 		return path;
246 	if ((p = getpwuid(getuid())) == NULL)
247 		return NULL;
248 	strlcpy(path, p->pw_dir, PATH_MAX);
249 	strlcat(path, _dothistory, PATH_MAX);
250 	return path;
251 }
252 
253 /*
254  * READLINE compatibility stuff
255  */
256 
257 /*
258  * Set the prompt
259  */
260 int
261 rl_set_prompt(const char *prompt)
262 {
263 	char *p;
264 
265 	if (!prompt)
266 		prompt = "";
267 	if (rl_prompt != NULL && strcmp(rl_prompt, prompt) == 0)
268 		return 0;
269 	if (rl_prompt)
270 		free(rl_prompt);
271 	rl_prompt = strdup(prompt);
272 	if (rl_prompt == NULL)
273 		return -1;
274 
275 	while ((p = strchr(rl_prompt, RL_PROMPT_END_IGNORE)) != NULL)
276 		*p = RL_PROMPT_START_IGNORE;
277 
278 	return 0;
279 }
280 
281 /*
282  * initialize rl compat stuff
283  */
284 int
285 rl_initialize(void)
286 {
287 	HistEvent ev;
288 	int editmode = 1;
289 	struct termios t;
290 
291 	current_history_valid = 1;
292 
293 	if (e != NULL)
294 		el_end(e);
295 	if (h != NULL)
296 		history_end(h);
297 
298 	if (!rl_instream)
299 		rl_instream = stdin;
300 	if (!rl_outstream)
301 		rl_outstream = stdout;
302 
303 	/*
304 	 * See if we don't really want to run the editor
305 	 */
306 	if (tcgetattr(fileno(rl_instream), &t) != -1 && (t.c_lflag & ECHO) == 0)
307 		editmode = 0;
308 
309 	e = el_init(rl_readline_name, rl_instream, rl_outstream, stderr);
310 
311 	if (!editmode)
312 		el_set(e, EL_EDITMODE, 0);
313 
314 	h = history_init();
315 	if (!e || !h)
316 		return -1;
317 
318 	history(h, &ev, H_SETSIZE, INT_MAX);	/* unlimited */
319 	history_length = 0;
320 	max_input_history = INT_MAX;
321 	el_set(e, EL_HIST, history, h);
322 
323 	/* Setup resize function */
324 	el_set(e, EL_RESIZE, _resize_fun, &rl_line_buffer);
325 
326 	/* setup getc function if valid */
327 	if (rl_getc_function)
328 		el_set(e, EL_GETCFN, _getc_function);
329 
330 	/* for proper prompt printing in readline() */
331 	if (rl_set_prompt("") == -1) {
332 		history_end(h);
333 		el_end(e);
334 		return -1;
335 	}
336 	el_set(e, EL_PROMPT, _get_prompt, RL_PROMPT_START_IGNORE);
337 	el_set(e, EL_SIGNAL, rl_catch_signals);
338 
339 	/* set default mode to "emacs"-style and read setting afterwards */
340 	/* so this can be overriden */
341 	el_set(e, EL_EDITOR, "emacs");
342 	if (rl_terminal_name != NULL)
343 		el_set(e, EL_TERMINAL, rl_terminal_name);
344 	else
345 		el_get(e, EL_TERMINAL, &rl_terminal_name);
346 
347 	/*
348 	 * Word completion - this has to go AFTER rebinding keys
349 	 * to emacs-style.
350 	 */
351 	el_set(e, EL_ADDFN, "rl_complete",
352 	    "ReadLine compatible completion function",
353 	    _el_rl_complete);
354 	el_set(e, EL_BIND, "^I", "rl_complete", NULL);
355 
356 	/*
357 	 * Send TSTP when ^Z is pressed.
358 	 */
359 	el_set(e, EL_ADDFN, "rl_tstp",
360 	    "ReadLine compatible suspend function",
361 	    _el_rl_tstp);
362 	el_set(e, EL_BIND, "^Z", "rl_tstp", NULL);
363 
364 	/* read settings from configuration file */
365 	el_source(e, NULL);
366 
367 	/*
368 	 * Unfortunately, some applications really do use rl_point
369 	 * and rl_line_buffer directly.
370 	 */
371 	_resize_fun(e, &rl_line_buffer);
372 	_rl_update_pos();
373 
374 	if (rl_startup_hook)
375 		(*rl_startup_hook)(NULL, 0);
376 
377 	return 0;
378 }
379 
380 
381 /*
382  * read one line from input stream and return it, chomping
383  * trailing newline (if there is any)
384  */
385 char *
386 readline(const char *p)
387 {
388 	HistEvent ev;
389 	const char * volatile prompt = p;
390 	int count;
391 	const char *ret;
392 	char *buf;
393 	static int used_event_hook;
394 
395 	if (e == NULL || h == NULL)
396 		rl_initialize();
397 
398 	rl_done = 0;
399 
400 	(void)setjmp(topbuf);
401 
402 	/* update prompt accordingly to what has been passed */
403 	if (rl_set_prompt(prompt) == -1)
404 		return NULL;
405 
406 	if (rl_pre_input_hook)
407 		(*rl_pre_input_hook)(NULL, 0);
408 
409 	if (rl_event_hook && !(e->el_flags&NO_TTY)) {
410 		el_set(e, EL_GETCFN, _rl_event_read_char);
411 		used_event_hook = 1;
412 	}
413 
414 	if (!rl_event_hook && used_event_hook) {
415 		el_set(e, EL_GETCFN, EL_BUILTIN_GETCFN);
416 		used_event_hook = 0;
417 	}
418 
419 	rl_already_prompted = 0;
420 
421 	/* get one line from input stream */
422 	ret = el_gets(e, &count);
423 
424 	if (ret && count > 0) {
425 		int lastidx;
426 
427 		buf = strdup(ret);
428 		if (buf == NULL)
429 			return NULL;
430 		lastidx = count - 1;
431 		if (buf[lastidx] == '\n')
432 			buf[lastidx] = '\0';
433 	} else
434 		buf = NULL;
435 
436 	history(h, &ev, H_GETSIZE);
437 	history_length = ev.num;
438 
439 	return buf;
440 }
441 
442 /*
443  * history functions
444  */
445 
446 /*
447  * is normally called before application starts to use
448  * history expansion functions
449  */
450 void
451 using_history(void)
452 {
453 	if (h == NULL || e == NULL)
454 		rl_initialize();
455 }
456 
457 
458 /*
459  * substitute ``what'' with ``with'', returning resulting string; if
460  * globally == 1, substitutes all occurrences of what, otherwise only the
461  * first one
462  */
463 static char *
464 _rl_compat_sub(const char *str, const char *what, const char *with,
465     int globally)
466 {
467 	const	char	*s;
468 	char	*r, *result;
469 	size_t	len, with_len, what_len;
470 
471 	len = strlen(str);
472 	with_len = strlen(with);
473 	what_len = strlen(what);
474 
475 	/* calculate length we need for result */
476 	s = str;
477 	while (*s) {
478 		if (*s == *what && !strncmp(s, what, what_len)) {
479 			len += with_len - what_len;
480 			if (!globally)
481 				break;
482 			s += what_len;
483 		} else
484 			s++;
485 	}
486 	r = result = malloc(len + 1);
487 	if (result == NULL)
488 		return NULL;
489 	s = str;
490 	while (*s) {
491 		if (*s == *what && !strncmp(s, what, what_len)) {
492 			(void)strncpy(r, with, with_len);
493 			r += with_len;
494 			s += what_len;
495 			if (!globally) {
496 				(void)strlcpy(r, s, len);
497 				return result;
498 			}
499 		} else
500 			*r++ = *s++;
501 	}
502 	*r = '\0';
503 	return result;
504 }
505 
506 static	char	*last_search_pat;	/* last !?pat[?] search pattern */
507 static	char	*last_search_match;	/* last !?pat[?] that matched */
508 
509 const char *
510 get_history_event(const char *cmd, int *cindex, int qchar)
511 {
512 	int idx, sign, sub, num, begin, ret;
513 	size_t len;
514 	char	*pat;
515 	const char *rptr;
516 	HistEvent ev;
517 
518 	idx = *cindex;
519 	if (cmd[idx++] != history_expansion_char)
520 		return NULL;
521 
522 	/* find out which event to take */
523 	if (cmd[idx] == history_expansion_char || cmd[idx] == '\0') {
524 		if (history(h, &ev, H_FIRST) != 0)
525 			return NULL;
526 		*cindex = cmd[idx]? (idx + 1):idx;
527 		return ev.str;
528 	}
529 	sign = 0;
530 	if (cmd[idx] == '-') {
531 		sign = 1;
532 		idx++;
533 	}
534 
535 	if ('0' <= cmd[idx] && cmd[idx] <= '9') {
536 		HIST_ENTRY *rl_he;
537 
538 		num = 0;
539 		while (cmd[idx] && '0' <= cmd[idx] && cmd[idx] <= '9') {
540 			num = num * 10 + cmd[idx] - '0';
541 			idx++;
542 		}
543 		if (sign)
544 			num = history_length - num + 1;
545 
546 		if (!(rl_he = history_get(num)))
547 			return NULL;
548 
549 		*cindex = idx;
550 		return rl_he->line;
551 	}
552 	sub = 0;
553 	if (cmd[idx] == '?') {
554 		sub = 1;
555 		idx++;
556 	}
557 	begin = idx;
558 	while (cmd[idx]) {
559 		if (cmd[idx] == '\n')
560 			break;
561 		if (sub && cmd[idx] == '?')
562 			break;
563 		if (!sub && (cmd[idx] == ':' || cmd[idx] == ' '
564 				    || cmd[idx] == '\t' || cmd[idx] == qchar))
565 			break;
566 		idx++;
567 	}
568 	len = idx - begin;
569 	if (sub && cmd[idx] == '?')
570 		idx++;
571 	if (sub && len == 0 && last_search_pat && *last_search_pat)
572 		pat = last_search_pat;
573 	else if (len == 0)
574 		return NULL;
575 	else {
576 		if ((pat = malloc(len + 1)) == NULL)
577 			return NULL;
578 		(void)strncpy(pat, cmd + begin, len);
579 		pat[len] = '\0';
580 	}
581 
582 	if (history(h, &ev, H_CURR) != 0) {
583 		if (pat != last_search_pat)
584 			free(pat);
585 		return NULL;
586 	}
587 	num = ev.num;
588 
589 	if (sub) {
590 		if (pat != last_search_pat) {
591 			if (last_search_pat)
592 				free(last_search_pat);
593 			last_search_pat = pat;
594 		}
595 		ret = history_search(pat, -1);
596 	} else
597 		ret = history_search_prefix(pat, -1);
598 
599 	if (ret == -1) {
600 		/* restore to end of list on failed search */
601 		history(h, &ev, H_FIRST);
602 		(void)fprintf(rl_outstream, "%s: Event not found\n", pat);
603 		if (pat != last_search_pat)
604 			free(pat);
605 		return NULL;
606 	}
607 
608 	if (sub && len) {
609 		if (last_search_match && last_search_match != pat)
610 			free(last_search_match);
611 		last_search_match = pat;
612 	}
613 
614 	if (pat != last_search_pat)
615 		free(pat);
616 
617 	if (history(h, &ev, H_CURR) != 0)
618 		return NULL;
619 	*cindex = idx;
620 	rptr = ev.str;
621 
622 	/* roll back to original position */
623 	(void)history(h, &ev, H_SET, num);
624 
625 	return rptr;
626 }
627 
628 /*
629  * the real function doing history expansion - takes as argument command
630  * to do and data upon which the command should be executed
631  * does expansion the way I've understood readline documentation
632  *
633  * returns 0 if data was not modified, 1 if it was and 2 if the string
634  * should be only printed and not executed; in case of error,
635  * returns -1 and *result points to NULL
636  * it's the caller's responsibility to free() the string returned in *result
637  */
638 static int
639 _history_expand_command(const char *command, size_t offs, size_t cmdlen,
640     char **result)
641 {
642 	char *tmp, *search = NULL, *aptr;
643 	const char *ptr, *cmd;
644 	static char *from = NULL, *to = NULL;
645 	int start, end, idx, has_mods = 0;
646 	int p_on = 0, g_on = 0;
647 
648 	*result = NULL;
649 	aptr = NULL;
650 	ptr = NULL;
651 
652 	/* First get event specifier */
653 	idx = 0;
654 
655 	if (strchr(":^*$", command[offs + 1])) {
656 		char str[4];
657 		/*
658 		* "!:" is shorthand for "!!:".
659 		* "!^", "!*" and "!$" are shorthand for
660 		* "!!:^", "!!:*" and "!!:$" respectively.
661 		*/
662 		str[0] = str[1] = '!';
663 		str[2] = '0';
664 		ptr = get_history_event(str, &idx, 0);
665 		idx = (command[offs + 1] == ':')? 1:0;
666 		has_mods = 1;
667 	} else {
668 		if (command[offs + 1] == '#') {
669 			/* use command so far */
670 			if ((aptr = malloc(offs + 1)) == NULL)
671 				return -1;
672 			(void)strncpy(aptr, command, offs);
673 			aptr[offs] = '\0';
674 			idx = 1;
675 		} else {
676 			int	qchar;
677 
678 			qchar = (offs > 0 && command[offs - 1] == '"')? '"':0;
679 			ptr = get_history_event(command + offs, &idx, qchar);
680 		}
681 		has_mods = command[offs + idx] == ':';
682 	}
683 
684 	if (ptr == NULL && aptr == NULL)
685 		return -1;
686 
687 	if (!has_mods) {
688 		*result = strdup(aptr ? aptr : ptr);
689 		if (aptr)
690 			free(aptr);
691 		if (*result == NULL)
692 			return -1;
693 		return 1;
694 	}
695 
696 	cmd = command + offs + idx + 1;
697 
698 	/* Now parse any word designators */
699 
700 	if (*cmd == '%')	/* last word matched by ?pat? */
701 		tmp = strdup(last_search_match? last_search_match:"");
702 	else if (strchr("^*$-0123456789", *cmd)) {
703 		start = end = -1;
704 		if (*cmd == '^')
705 			start = end = 1, cmd++;
706 		else if (*cmd == '$')
707 			start = -1, cmd++;
708 		else if (*cmd == '*')
709 			start = 1, cmd++;
710 	       else if (*cmd == '-' || isdigit((unsigned char) *cmd)) {
711 			start = 0;
712 			while (*cmd && '0' <= *cmd && *cmd <= '9')
713 				start = start * 10 + *cmd++ - '0';
714 
715 			if (*cmd == '-') {
716 				if (isdigit((unsigned char) cmd[1])) {
717 					cmd++;
718 					end = 0;
719 					while (*cmd && '0' <= *cmd && *cmd <= '9')
720 						end = end * 10 + *cmd++ - '0';
721 				} else if (cmd[1] == '$') {
722 					cmd += 2;
723 					end = -1;
724 				} else {
725 					cmd++;
726 					end = -2;
727 				}
728 			} else if (*cmd == '*')
729 				end = -1, cmd++;
730 			else
731 				end = start;
732 		}
733 		tmp = history_arg_extract(start, end, aptr? aptr:ptr);
734 		if (tmp == NULL) {
735 			(void)fprintf(rl_outstream, "%s: Bad word specifier",
736 			    command + offs + idx);
737 			if (aptr)
738 				free(aptr);
739 			return -1;
740 		}
741 	} else
742 		tmp = strdup(aptr? aptr:ptr);
743 
744 	if (aptr)
745 		free(aptr);
746 
747 	if (*cmd == '\0' || ((size_t)(cmd - (command + offs)) >= cmdlen)) {
748 		*result = tmp;
749 		return 1;
750 	}
751 
752 	for (; *cmd; cmd++) {
753 		if (*cmd == ':')
754 			continue;
755 		else if (*cmd == 'h') {		/* remove trailing path */
756 			if ((aptr = strrchr(tmp, '/')) != NULL)
757 				*aptr = '\0';
758 		} else if (*cmd == 't') {	/* remove leading path */
759 			if ((aptr = strrchr(tmp, '/')) != NULL) {
760 				aptr = strdup(aptr + 1);
761 				free(tmp);
762 				tmp = aptr;
763 			}
764 		} else if (*cmd == 'r') {	/* remove trailing suffix */
765 			if ((aptr = strrchr(tmp, '.')) != NULL)
766 				*aptr = '\0';
767 		} else if (*cmd == 'e') {	/* remove all but suffix */
768 			if ((aptr = strrchr(tmp, '.')) != NULL) {
769 				aptr = strdup(aptr);
770 				free(tmp);
771 				tmp = aptr;
772 			}
773 		} else if (*cmd == 'p')		/* print only */
774 			p_on = 1;
775 		else if (*cmd == 'g')
776 			g_on = 2;
777 		else if (*cmd == 's' || *cmd == '&') {
778 			char *what, *with, delim;
779 			size_t len, from_len;
780 			size_t size;
781 
782 			if (*cmd == '&' && (from == NULL || to == NULL))
783 				continue;
784 			else if (*cmd == 's') {
785 				delim = *(++cmd), cmd++;
786 				size = 16;
787 				what = realloc(from, size);
788 				if (what == NULL) {
789 					free(from);
790 					free(tmp);
791 					return 0;
792 				}
793 				len = 0;
794 				for (; *cmd && *cmd != delim; cmd++) {
795 					if (*cmd == '\\' && cmd[1] == delim)
796 						cmd++;
797 					if (len >= size) {
798 						char *nwhat;
799 						nwhat = reallocarray(what,
800 						    size, 2);
801 						if (nwhat == NULL) {
802 							free(what);
803 							free(tmp);
804 							return 0;
805 						}
806 						size *= 2;
807 						what = nwhat;
808 					}
809 					what[len++] = *cmd;
810 				}
811 				what[len] = '\0';
812 				from = what;
813 				if (*what == '\0') {
814 					free(what);
815 					if (search) {
816 						from = strdup(search);
817 						if (from == NULL) {
818 							free(tmp);
819 							return 0;
820 						}
821 					} else {
822 						from = NULL;
823 						free(tmp);
824 						return -1;
825 					}
826 				}
827 				cmd++;	/* shift after delim */
828 				if (!*cmd)
829 					continue;
830 
831 				size = 16;
832 				with = realloc(to, size);
833 				if (with == NULL) {
834 					free(to);
835 					free(tmp);
836 					return -1;
837 				}
838 				len = 0;
839 				from_len = strlen(from);
840 				for (; *cmd && *cmd != delim; cmd++) {
841 					if (len + from_len + 1 >= size) {
842 						char *nwith;
843 						size += from_len + 1;
844 						nwith = realloc(with, size);
845 						if (nwith == NULL) {
846 							free(with);
847 							free(tmp);
848 							return -1;
849 						}
850 						with = nwith;
851 					}
852 					if (*cmd == '&') {
853 						/* safe */
854 						(void)strlcpy(&with[len], from,
855 						    size - len);
856 						len += from_len;
857 						continue;
858 					}
859 					if (*cmd == '\\'
860 					    && (*(cmd + 1) == delim
861 						|| *(cmd + 1) == '&'))
862 						cmd++;
863 					with[len++] = *cmd;
864 				}
865 				with[len] = '\0';
866 				to = with;
867 			}
868 
869 			aptr = _rl_compat_sub(tmp, from, to, g_on);
870 			if (aptr) {
871 				free(tmp);
872 				tmp = aptr;
873 			}
874 			g_on = 0;
875 		}
876 	}
877 	*result = tmp;
878 	return p_on? 2:1;
879 }
880 
881 
882 /*
883  * csh-style history expansion
884  */
885 int
886 history_expand(char *str, char **output)
887 {
888 	int ret = 0;
889 	size_t idx, i, size;
890 	char *tmp, *result;
891 
892 	if (h == NULL || e == NULL)
893 		rl_initialize();
894 
895 	if (history_expansion_char == 0) {
896 		*output = strdup(str);
897 		return 0;
898 	}
899 
900 	*output = NULL;
901 	if (str[0] == history_subst_char) {
902 		/* ^foo^foo2^ is equivalent to !!:s^foo^foo2^ */
903 		size_t sz = 4 + strlen(str) + 1;
904 		*output = malloc(sz);
905 		if (*output == NULL)
906 			return 0;
907 		(*output)[0] = (*output)[1] = history_expansion_char;
908 		(*output)[2] = ':';
909 		(*output)[3] = 's';
910 		(void)strlcpy((*output) + 4, str, sz - 4);
911 		str = *output;
912 	} else {
913 		*output = strdup(str);
914 		if (*output == NULL)
915 			return 0;
916 	}
917 
918 #define ADD_STRING(what, len, fr)					\
919 	{								\
920 		if (idx + len + 1 > size) {				\
921 			char *nresult = realloc(result, (size += len + 1));\
922 			if (nresult == NULL) {				\
923 				free(*output);				\
924 				if (/*CONSTCOND*/fr)			\
925 					free(tmp);			\
926 				return 0;				\
927 			}						\
928 			result = nresult;				\
929 		}							\
930 		(void)strncpy(&result[idx], what, len);			\
931 		idx += len;						\
932 		result[idx] = '\0';					\
933 	}
934 
935 	result = NULL;
936 	size = idx = 0;
937 	tmp = NULL;
938 	for (i = 0; str[i];) {
939 		int qchar, loop_again;
940 		size_t len, start, j;
941 
942 		qchar = 0;
943 		loop_again = 1;
944 		start = j = i;
945 loop:
946 		for (; str[j]; j++) {
947 			if (str[j] == '\\' &&
948 			    str[j + 1] == history_expansion_char) {
949 				size_t sz = strlen(&str[j]) + 1;
950 				(void)strlcpy(&str[j], &str[j + 1], sz);
951 				continue;
952 			}
953 			if (!loop_again) {
954 				if (isspace((unsigned char) str[j])
955 				    || str[j] == qchar)
956 					break;
957 			}
958 			if (str[j] == history_expansion_char
959 			    && !strchr(history_no_expand_chars, str[j + 1])
960 			    && (!history_inhibit_expansion_function ||
961 			    (*history_inhibit_expansion_function)(str,
962 			    (int)j) == 0))
963 				break;
964 		}
965 
966 		if (str[j] && loop_again) {
967 			i = j;
968 			qchar = (j > 0 && str[j - 1] == '"' )? '"':0;
969 			j++;
970 			if (str[j] == history_expansion_char)
971 				j++;
972 			loop_again = 0;
973 			goto loop;
974 		}
975 		len = i - start;
976 		ADD_STRING(&str[start], len, 0);
977 
978 		if (str[i] == '\0' || str[i] != history_expansion_char) {
979 			len = j - i;
980 			ADD_STRING(&str[i], len, 0);
981 			if (start == 0)
982 				ret = 0;
983 			else
984 				ret = 1;
985 			break;
986 		}
987 		ret = _history_expand_command (str, i, (j - i), &tmp);
988 		if (ret > 0 && tmp) {
989 			len = strlen(tmp);
990 			ADD_STRING(tmp, len, 1);
991 		}
992 		if (tmp) {
993 			free(tmp);
994 			tmp = NULL;
995 		}
996 		i = j;
997 	}
998 
999 	/* ret is 2 for "print only" option */
1000 	if (ret == 2) {
1001 		add_history(result);
1002 #ifdef GDB_411_HACK
1003 		/* gdb 4.11 has been shipped with readline, where */
1004 		/* history_expand() returned -1 when the line	  */
1005 		/* should not be executed; in readline 2.1+	  */
1006 		/* it should return 2 in such a case		  */
1007 		ret = -1;
1008 #endif
1009 	}
1010 	free(*output);
1011 	*output = result;
1012 
1013 	return ret;
1014 }
1015 
1016 /*
1017 * Return a string consisting of arguments of "str" from "start" to "end".
1018 */
1019 char *
1020 history_arg_extract(int start, int end, const char *str)
1021 {
1022 	size_t  i, len, max;
1023 	char	**arr, *result = NULL;
1024 
1025 	arr = history_tokenize(str);
1026 	if (!arr)
1027 		return NULL;
1028 	if (arr && *arr == NULL)
1029 		goto out;
1030 
1031 	for (max = 0; arr[max]; max++)
1032 		continue;
1033 	max--;
1034 
1035 	if (start == '$')
1036 		start = (int)max;
1037 	if (end == '$')
1038 		end = (int)max;
1039 	if (end < 0)
1040 		end = (int)max + end + 1;
1041 	if (start < 0)
1042 		start = end;
1043 
1044 	if (start < 0 || end < 0 || (size_t)start > max ||
1045 	    (size_t)end > max || start > end)
1046 		goto out;
1047 
1048 	for (i = start, len = 0; i <= (size_t)end; i++)
1049 		len += strlen(arr[i]) + 1;
1050 	len++;
1051 	max = len;
1052 	result = malloc(len);
1053 	if (result == NULL)
1054 		goto out;
1055 
1056 	for (i = start, len = 0; i <= (size_t)end; i++) {
1057 		(void)strlcpy(result + len, arr[i], max - len);
1058 		len += strlen(arr[i]);
1059 		if (i < (size_t)end)
1060 			result[len++] = ' ';
1061 	}
1062 	result[len] = '\0';
1063 
1064 out:
1065 	for (i = 0; arr[i]; i++)
1066 		free(arr[i]);
1067 	free(arr);
1068 
1069 	return result;
1070 }
1071 
1072 /*
1073  * Parse the string into individual tokens,
1074  * similar to how shell would do it.
1075  */
1076 char **
1077 history_tokenize(const char *str)
1078 {
1079 	int size = 1, idx = 0, i, start;
1080 	size_t len;
1081 	char **result = NULL, *temp, delim = '\0';
1082 
1083 	for (i = 0; str[i];) {
1084 		while (isspace((unsigned char) str[i]))
1085 			i++;
1086 		start = i;
1087 		for (; str[i];) {
1088 			if (str[i] == '\\') {
1089 				if (str[i+1] != '\0')
1090 					i++;
1091 			} else if (str[i] == delim)
1092 				delim = '\0';
1093 			else if (!delim &&
1094 				    (isspace((unsigned char) str[i]) ||
1095 				strchr("()<>;&|$", str[i])))
1096 				break;
1097 			else if (!delim && strchr("'`\"", str[i]))
1098 				delim = str[i];
1099 			if (str[i])
1100 				i++;
1101 		}
1102 
1103 		if (idx + 2 >= size) {
1104 			char **nresult;
1105 			nresult = reallocarray(result, size,
1106 			    2 * sizeof(char *));
1107 			if (nresult == NULL) {
1108 				free(result);
1109 				return NULL;
1110 			}
1111 			size *= 2;
1112 			result = nresult;
1113 		}
1114 		len = i - start;
1115 		temp = malloc(len + 1);
1116 		if (temp == NULL) {
1117 			for (i = 0; i < idx; i++)
1118 				free(result[i]);
1119 			free(result);
1120 			return NULL;
1121 		}
1122 		(void)strncpy(temp, &str[start], len);
1123 		temp[len] = '\0';
1124 		result[idx++] = temp;
1125 		result[idx] = NULL;
1126 		if (str[i])
1127 			i++;
1128 	}
1129 	return result;
1130 }
1131 
1132 
1133 /*
1134  * limit size of history record to ``max'' events
1135  */
1136 void
1137 stifle_history(int max)
1138 {
1139 	HistEvent ev;
1140 	HIST_ENTRY *he;
1141 	int i, len;
1142 
1143 	if (h == NULL || e == NULL)
1144 		rl_initialize();
1145 
1146 	len = history_length;
1147 	if (history(h, &ev, H_SETSIZE, max) == 0) {
1148 		max_input_history = max;
1149 		if (max < len)
1150 			history_base += len - max;
1151 		for (i = 0; i < len - max; i++) {
1152 			he = remove_history(0);
1153 			free(he->data);
1154 			free((void *)he->line);
1155 			free(he);
1156 		}
1157 	}
1158 }
1159 
1160 
1161 /*
1162  * "unlimit" size of history - set the limit to maximum allowed int value
1163  */
1164 int
1165 unstifle_history(void)
1166 {
1167 	HistEvent ev;
1168 	int omax;
1169 
1170 	history(h, &ev, H_SETSIZE, INT_MAX);
1171 	omax = max_input_history;
1172 	max_input_history = INT_MAX;
1173 	return omax;		/* some value _must_ be returned */
1174 }
1175 
1176 
1177 int
1178 history_is_stifled(void)
1179 {
1180 
1181 	/* cannot return true answer */
1182 	return max_input_history != INT_MAX;
1183 }
1184 
1185 static const char _history_tmp_template[] = "/tmp/.historyXXXXXX";
1186 
1187 int
1188 history_truncate_file (const char *filename, int nlines)
1189 {
1190 	int ret = 0;
1191 	FILE *fp, *tp;
1192 	char template[sizeof(_history_tmp_template)];
1193 	char buf[4096];
1194 	int fd;
1195 	char *cp;
1196 	off_t off;
1197 	int count = 0;
1198 	ssize_t left = 0;
1199 
1200 	if (filename == NULL && (filename = _default_history_file()) == NULL)
1201 		return errno;
1202 	if ((fp = fopen(filename, "r+")) == NULL)
1203 		return errno;
1204 	strlcpy(template, _history_tmp_template, sizeof(template));
1205 	if ((fd = mkstemp(template)) == -1) {
1206 		ret = errno;
1207 		goto out1;
1208 	}
1209 
1210 	if ((tp = fdopen(fd, "r+")) == NULL) {
1211 		close(fd);
1212 		ret = errno;
1213 		goto out2;
1214 	}
1215 
1216 	for(;;) {
1217 		if (fread(buf, sizeof(buf), 1, fp) != 1) {
1218 			if (ferror(fp)) {
1219 				ret = errno;
1220 				break;
1221 			}
1222 			if (fseeko(fp, (off_t)sizeof(buf) * count, SEEK_SET) ==
1223 			    (off_t)-1) {
1224 				ret = errno;
1225 				break;
1226 			}
1227 			left = fread(buf, 1, sizeof(buf), fp);
1228 			if (ferror(fp)) {
1229 				ret = errno;
1230 				break;
1231 			}
1232 			if (left == 0) {
1233 				count--;
1234 				left = sizeof(buf);
1235 			} else if (fwrite(buf, (size_t)left, 1, tp) != 1) {
1236 				ret = errno;
1237 				break;
1238 			}
1239 			fflush(tp);
1240 			break;
1241 		}
1242 		if (fwrite(buf, sizeof(buf), 1, tp) != 1) {
1243 			ret = errno;
1244 			break;
1245 		}
1246 		count++;
1247 	}
1248 	if (ret)
1249 		goto out3;
1250 	cp = buf + left - 1;
1251 	if(*cp != '\n')
1252 		cp++;
1253 	for(;;) {
1254 		while (--cp >= buf) {
1255 			if (*cp == '\n') {
1256 				if (--nlines == 0) {
1257 					if (++cp >= buf + sizeof(buf)) {
1258 						count++;
1259 						cp = buf;
1260 					}
1261 					break;
1262 				}
1263 			}
1264 		}
1265 		if (nlines <= 0 || count == 0)
1266 			break;
1267 		count--;
1268 		if (fseeko(tp, (off_t)sizeof(buf) * count, SEEK_SET) == -1) {
1269 			ret = errno;
1270 			break;
1271 		}
1272 		if (fread(buf, sizeof(buf), 1, tp) != 1) {
1273 			if (ferror(tp)) {
1274 				ret = errno;
1275 				break;
1276 			}
1277 			ret = EAGAIN;
1278 			break;
1279 		}
1280 		cp = buf + sizeof(buf);
1281 	}
1282 
1283 	if (ret || nlines > 0)
1284 		goto out3;
1285 
1286 	if (fseeko(fp, 0, SEEK_SET) == (off_t)-1) {
1287 		ret = errno;
1288 		goto out3;
1289 	}
1290 
1291 	if (fseeko(tp, (off_t)sizeof(buf) * count + (cp - buf), SEEK_SET) ==
1292 	    (off_t)-1) {
1293 		ret = errno;
1294 		goto out3;
1295 	}
1296 
1297 	for(;;) {
1298 		if ((left = fread(buf, 1, sizeof(buf), tp)) == 0) {
1299 			if (ferror(fp))
1300 				ret = errno;
1301 			break;
1302 		}
1303 		if (fwrite(buf, (size_t)left, 1, fp) != 1) {
1304 			ret = errno;
1305 			break;
1306 		}
1307 	}
1308 	fflush(fp);
1309 	if((off = ftello(fp)) > 0)
1310 		(void)ftruncate(fileno(fp), off);
1311 out3:
1312 	fclose(tp);
1313 out2:
1314 	unlink(template);
1315 out1:
1316 	fclose(fp);
1317 
1318 	return ret;
1319 }
1320 
1321 
1322 /*
1323  * read history from a file given
1324  */
1325 int
1326 read_history(const char *filename)
1327 {
1328 	HistEvent ev;
1329 
1330 	if (h == NULL || e == NULL)
1331 		rl_initialize();
1332 	if (filename == NULL && (filename = _default_history_file()) == NULL)
1333 		return errno;
1334 	return history(h, &ev, H_LOAD, filename) == -1 ?
1335 	    (errno ? errno : EINVAL) : 0;
1336 }
1337 
1338 
1339 /*
1340  * write history to a file given
1341  */
1342 int
1343 write_history(const char *filename)
1344 {
1345 	HistEvent ev;
1346 
1347 	if (h == NULL || e == NULL)
1348 		rl_initialize();
1349 	if (filename == NULL && (filename = _default_history_file()) == NULL)
1350 		return errno;
1351 	return history(h, &ev, H_SAVE, filename) == -1 ?
1352 	    (errno ? errno : EINVAL) : 0;
1353 }
1354 
1355 
1356 /*
1357  * returns history ``num''th event
1358  *
1359  * returned pointer points to static variable
1360  */
1361 HIST_ENTRY *
1362 history_get(int num)
1363 {
1364 	static HIST_ENTRY she;
1365 	HistEvent ev;
1366 	int curr_num;
1367 
1368 	if (h == NULL || e == NULL)
1369 		rl_initialize();
1370 
1371 	if (num < history_base)
1372 		return NULL;
1373 
1374 	/* save current position */
1375 	if (history(h, &ev, H_CURR) != 0)
1376 		return NULL;
1377 	curr_num = ev.num;
1378 
1379 	/*
1380 	 * use H_DELDATA to set to nth history (without delete) by passing
1381 	 * (void **)-1  -- as in history_set_pos
1382 	 */
1383 	if (history(h, &ev, H_DELDATA, num - history_base, (void **)-1) != 0)
1384 		goto out;
1385 
1386 	/* get current entry */
1387 	if (history(h, &ev, H_CURR) != 0)
1388 		goto out;
1389 	if (history(h, &ev, H_NEXT_EVDATA, ev.num, &she.data) != 0)
1390 		goto out;
1391 	she.line = ev.str;
1392 
1393 	/* restore pointer to where it was */
1394 	(void)history(h, &ev, H_SET, curr_num);
1395 
1396 	return &she;
1397 
1398 out:
1399 	/* restore pointer to where it was */
1400 	(void)history(h, &ev, H_SET, curr_num);
1401 	return NULL;
1402 }
1403 
1404 
1405 /*
1406  * add the line to history table
1407  */
1408 int
1409 add_history(const char *line)
1410 {
1411 	HistEvent ev;
1412 
1413 	if (h == NULL || e == NULL)
1414 		rl_initialize();
1415 
1416 	(void)history(h, &ev, H_ENTER, line);
1417 	if (history(h, &ev, H_GETSIZE) == 0)
1418 		history_length = ev.num;
1419 	current_history_valid = 1;
1420 
1421 	return !(history_length > 0); /* return 0 if all is okay */
1422 }
1423 
1424 
1425 /*
1426  * remove the specified entry from the history list and return it.
1427  */
1428 HIST_ENTRY *
1429 remove_history(int num)
1430 {
1431 	HIST_ENTRY *he;
1432 	HistEvent ev;
1433 
1434 	if (h == NULL || e == NULL)
1435 		rl_initialize();
1436 
1437 	if ((he = malloc(sizeof(*he))) == NULL)
1438 		return NULL;
1439 
1440 	if (history(h, &ev, H_DELDATA, num, &he->data) != 0) {
1441 		free(he);
1442 		return NULL;
1443 	}
1444 
1445 	he->line = ev.str;
1446 	if (history(h, &ev, H_GETSIZE) == 0)
1447 		history_length = ev.num;
1448 
1449 	return he;
1450 }
1451 
1452 
1453 /*
1454  * replace the line and data of the num-th entry
1455  */
1456 HIST_ENTRY *
1457 replace_history_entry(int num, const char *line, histdata_t data)
1458 {
1459 	HIST_ENTRY *he;
1460 	HistEvent ev;
1461 	int curr_num;
1462 
1463 	if (h == NULL || e == NULL)
1464 		rl_initialize();
1465 
1466 	/* save current position */
1467 	if (history(h, &ev, H_CURR) != 0)
1468 		return NULL;
1469 	curr_num = ev.num;
1470 
1471 	/* start from the oldest */
1472 	if (history(h, &ev, H_LAST) != 0)
1473 		return NULL;	/* error */
1474 
1475 	if ((he = malloc(sizeof(*he))) == NULL)
1476 		return NULL;
1477 
1478 	/* look forwards for event matching specified offset */
1479 	if (history(h, &ev, H_NEXT_EVDATA, num, &he->data))
1480 		goto out;
1481 
1482 	he->line = strdup(ev.str);
1483 	if (he->line == NULL)
1484 		goto out;
1485 
1486 	if (history(h, &ev, H_REPLACE, line, data))
1487 		goto out;
1488 
1489 	/* restore pointer to where it was */
1490 	if (history(h, &ev, H_SET, curr_num))
1491 		goto out;
1492 
1493 	return he;
1494 out:
1495 	free(he);
1496 	return NULL;
1497 }
1498 
1499 /*
1500  * clear the history list - delete all entries
1501  */
1502 void
1503 clear_history(void)
1504 {
1505 	HistEvent ev;
1506 
1507 	(void)history(h, &ev, H_CLEAR);
1508 	history_length = 0;
1509 	current_history_valid = 1;
1510 }
1511 
1512 
1513 /*
1514  * returns offset of the current history event
1515  */
1516 int
1517 where_history(void)
1518 {
1519 	HistEvent ev;
1520 	int curr_num, off;
1521 
1522 	if (history(h, &ev, H_CURR) != 0)
1523 		return 0;
1524 	curr_num = ev.num;
1525 
1526 	/* start from the oldest */
1527 	(void)history(h, &ev, H_LAST);
1528 
1529 	/* position is zero-based */
1530 	off = 0;
1531 	while (ev.num != curr_num && history(h, &ev, H_PREV) == 0)
1532 		off++;
1533 
1534 	return off;
1535 }
1536 
1537 
1538 /*
1539  * returns current history event or NULL if there is no such event
1540  */
1541 HIST_ENTRY *
1542 current_history(void)
1543 {
1544 
1545 	return current_history_valid ? _move_history(H_CURR) : NULL;
1546 }
1547 
1548 
1549 /*
1550  * returns total number of bytes history events' data are using
1551  */
1552 int
1553 history_total_bytes(void)
1554 {
1555 	HistEvent ev;
1556 	int curr_num;
1557 	size_t size;
1558 
1559 	if (history(h, &ev, H_CURR) != 0)
1560 		return -1;
1561 	curr_num = ev.num;
1562 
1563 	(void)history(h, &ev, H_FIRST);
1564 	size = 0;
1565 	do
1566 		size += strlen(ev.str) * sizeof(*ev.str);
1567 	while (history(h, &ev, H_NEXT) == 0);
1568 
1569 	/* get to the same position as before */
1570 	history(h, &ev, H_PREV_EVENT, curr_num);
1571 
1572 	return (int)size;
1573 }
1574 
1575 
1576 /*
1577  * sets the position in the history list to ``pos''
1578  */
1579 int
1580 history_set_pos(int pos)
1581 {
1582 	HistEvent ev;
1583 	int curr_num;
1584 
1585 	if (pos >= history_length || pos < 0)
1586 		return 0;
1587 
1588 	(void)history(h, &ev, H_CURR);
1589 	curr_num = ev.num;
1590 	current_history_valid = 1;
1591 
1592 	/*
1593 	 * use H_DELDATA to set to nth history (without delete) by passing
1594 	 * (void **)-1
1595 	 */
1596 	if (history(h, &ev, H_DELDATA, pos, (void **)-1)) {
1597 		(void)history(h, &ev, H_SET, curr_num);
1598 		return 0;
1599 	}
1600 	return 1;
1601 }
1602 
1603 
1604 /*
1605  * returns previous event in history and shifts pointer accordingly
1606  * Note that readline and editline define directions in opposite ways.
1607  */
1608 HIST_ENTRY *
1609 previous_history(void)
1610 {
1611 
1612 	if (current_history_valid == 0) {
1613 		current_history_valid = 1;
1614 		return _move_history(H_CURR);
1615 	}
1616 	return _move_history(H_NEXT);
1617 }
1618 
1619 
1620 /*
1621  * returns next event in history and shifts pointer accordingly
1622  */
1623 HIST_ENTRY *
1624 next_history(void)
1625 {
1626 	HIST_ENTRY *he;
1627 
1628 	he = _move_history(H_PREV);
1629 	if (he == NULL)
1630 		current_history_valid = 0;
1631 	return he;
1632 }
1633 
1634 
1635 /*
1636  * searches for first history event containing the str
1637  */
1638 int
1639 history_search(const char *str, int direction)
1640 {
1641 	HistEvent ev;
1642 	const char *strp;
1643 	int curr_num;
1644 
1645 	if (history(h, &ev, H_CURR) != 0)
1646 		return -1;
1647 	curr_num = ev.num;
1648 
1649 	for (;;) {
1650 		if ((strp = strstr(ev.str, str)) != NULL)
1651 			return (int)(strp - ev.str);
1652 		if (history(h, &ev, direction < 0 ? H_NEXT:H_PREV) != 0)
1653 			break;
1654 	}
1655 	(void)history(h, &ev, H_SET, curr_num);
1656 	return -1;
1657 }
1658 
1659 
1660 /*
1661  * searches for first history event beginning with str
1662  */
1663 int
1664 history_search_prefix(const char *str, int direction)
1665 {
1666 	HistEvent ev;
1667 
1668 	return (history(h, &ev, direction < 0 ?
1669 	    H_PREV_STR : H_NEXT_STR, str));
1670 }
1671 
1672 
1673 /*
1674  * search for event in history containing str, starting at offset
1675  * abs(pos); continue backward, if pos<0, forward otherwise
1676  */
1677 /* ARGSUSED */
1678 int
1679 history_search_pos(const char *str,
1680 		   int direction __attribute__((__unused__)), int pos)
1681 {
1682 	HistEvent ev;
1683 	int curr_num, off;
1684 
1685 	off = (pos > 0) ? pos : -pos;
1686 	pos = (pos > 0) ? 1 : -1;
1687 
1688 	if (history(h, &ev, H_CURR) != 0)
1689 		return -1;
1690 	curr_num = ev.num;
1691 
1692 	if (!history_set_pos(off) || history(h, &ev, H_CURR) != 0)
1693 		return -1;
1694 
1695 	for (;;) {
1696 		if (strstr(ev.str, str))
1697 			return off;
1698 		if (history(h, &ev, (pos < 0) ? H_PREV : H_NEXT) != 0)
1699 			break;
1700 	}
1701 
1702 	/* set "current" pointer back to previous state */
1703 	(void)history(h, &ev,
1704 	    pos < 0 ? H_NEXT_EVENT : H_PREV_EVENT, curr_num);
1705 
1706 	return -1;
1707 }
1708 
1709 
1710 /********************************/
1711 /* completion functions */
1712 
1713 char *
1714 tilde_expand(char *name)
1715 {
1716 	return fn_tilde_expand(name);
1717 }
1718 
1719 char *
1720 filename_completion_function(const char *name, int state)
1721 {
1722 	return fn_filename_completion_function(name, state);
1723 }
1724 
1725 /*
1726  * a completion generator for usernames; returns _first_ username
1727  * which starts with supplied text
1728  * text contains a partial username preceded by random character
1729  * (usually '~'); state is ignored
1730  * it's the caller's responsibility to free the returned value
1731  */
1732 char *
1733 username_completion_function(const char *text, int state)
1734 {
1735 	struct passwd *pwd;
1736 
1737 	if (text[0] == '\0')
1738 		return NULL;
1739 
1740 	if (*text == '~')
1741 		text++;
1742 
1743 	if (state == 0)
1744 		setpwent();
1745 
1746 	while ((pwd = getpwent()) != NULL && text[0] == pwd->pw_name[0]
1747 	    && strcmp(text, pwd->pw_name) == 0);
1748 
1749 	if (pwd == NULL) {
1750 		endpwent();
1751 		return NULL;
1752 	}
1753 	return strdup(pwd->pw_name);
1754 }
1755 
1756 
1757 /*
1758  * el-compatible wrapper to send TSTP on ^Z
1759  */
1760 /* ARGSUSED */
1761 static unsigned char
1762 _el_rl_tstp(EditLine *el __attribute__((__unused__)), int ch __attribute__((__unused__)))
1763 {
1764 	(void)kill(0, SIGTSTP);
1765 	return CC_NORM;
1766 }
1767 
1768 /*
1769  * Display list of strings in columnar format on readline's output stream.
1770  * 'matches' is list of strings, 'len' is number of strings in 'matches',
1771  * 'max' is maximum length of string in 'matches'.
1772  */
1773 void
1774 rl_display_match_list(char **matches, int len, int max)
1775 {
1776 
1777 	fn_display_match_list(e, matches, (size_t)len, (size_t)max);
1778 }
1779 
1780 static const char *
1781 /*ARGSUSED*/
1782 _rl_completion_append_character_function(const char *dummy
1783     __attribute__((__unused__)))
1784 {
1785 	static char buf[2];
1786 	buf[0] = rl_completion_append_character;
1787 	buf[1] = '\0';
1788 	return buf;
1789 }
1790 
1791 
1792 /*
1793  * complete word at current point
1794  */
1795 /* ARGSUSED */
1796 int
1797 rl_complete(int ignore __attribute__((__unused__)), int invoking_key)
1798 {
1799 	static ct_buffer_t wbreak_conv, sprefix_conv;
1800 
1801 	if (h == NULL || e == NULL)
1802 		rl_initialize();
1803 
1804 	if (rl_inhibit_completion) {
1805 		char arr[2];
1806 		arr[0] = (char)invoking_key;
1807 		arr[1] = '\0';
1808 		el_insertstr(e, arr);
1809 		return CC_REFRESH;
1810 	}
1811 
1812 	/* Just look at how many global variables modify this operation! */
1813 	return fn_complete(e,
1814 	    (CPFunction *)rl_completion_entry_function,
1815 	    rl_attempted_completion_function,
1816 	    ct_decode_string(rl_basic_word_break_characters, &wbreak_conv),
1817 	    ct_decode_string(rl_special_prefixes, &sprefix_conv),
1818 	    _rl_completion_append_character_function,
1819 	    (size_t)rl_completion_query_items,
1820 	    &rl_completion_type, &rl_attempted_completion_over,
1821 	    &rl_point, &rl_end);
1822 
1823 
1824 }
1825 
1826 
1827 /* ARGSUSED */
1828 static unsigned char
1829 _el_rl_complete(EditLine *el __attribute__((__unused__)), int ch)
1830 {
1831 	return (unsigned char)rl_complete(0, ch);
1832 }
1833 
1834 /*
1835  * misc other functions
1836  */
1837 
1838 /*
1839  * bind key c to readline-type function func
1840  */
1841 int
1842 rl_bind_key(int c, rl_command_func_t *func)
1843 {
1844 	int retval = -1;
1845 
1846 	if (h == NULL || e == NULL)
1847 		rl_initialize();
1848 
1849 	if (func == rl_insert) {
1850 		/* XXX notice there is no range checking of ``c'' */
1851 		e->el_map.key[c] = ED_INSERT;
1852 		retval = 0;
1853 	}
1854 	return retval;
1855 }
1856 
1857 
1858 /*
1859  * read one key from input - handles chars pushed back
1860  * to input stream also
1861  */
1862 int
1863 rl_read_key(void)
1864 {
1865 	char fooarr[2 * sizeof(int)];
1866 
1867 	if (e == NULL || h == NULL)
1868 		rl_initialize();
1869 
1870 	return el_getc(e, fooarr);
1871 }
1872 
1873 
1874 /*
1875  * reset the terminal
1876  */
1877 /* ARGSUSED */
1878 void
1879 rl_reset_terminal(const char *p __attribute__((__unused__)))
1880 {
1881 
1882 	if (h == NULL || e == NULL)
1883 		rl_initialize();
1884 	el_reset(e);
1885 }
1886 
1887 
1888 /*
1889  * insert character ``c'' back into input stream, ``count'' times
1890  */
1891 int
1892 rl_insert(int count, int c)
1893 {
1894 	char arr[2];
1895 
1896 	if (h == NULL || e == NULL)
1897 		rl_initialize();
1898 
1899 	/* XXX - int -> char conversion can lose on multichars */
1900 	arr[0] = c;
1901 	arr[1] = '\0';
1902 
1903 	for (; count > 0; count--)
1904 		el_push(e, arr);
1905 
1906 	return 0;
1907 }
1908 
1909 int
1910 rl_insert_text(const char *text)
1911 {
1912 	if (!text || *text == 0)
1913 		return 0;
1914 
1915 	if (h == NULL || e == NULL)
1916 		rl_initialize();
1917 
1918 	if (el_insertstr(e, text) < 0)
1919 		return 0;
1920 	return (int)strlen(text);
1921 }
1922 
1923 /*ARGSUSED*/
1924 int
1925 rl_newline(int count, int c)
1926 {
1927 	/*
1928 	 * Readline-4.0 appears to ignore the args.
1929 	 */
1930 	return rl_insert(1, '\n');
1931 }
1932 
1933 /*ARGSUSED*/
1934 static unsigned char
1935 rl_bind_wrapper(EditLine *el, unsigned char c)
1936 {
1937 	if (map[c] == NULL)
1938 	    return CC_ERROR;
1939 
1940 	_rl_update_pos();
1941 
1942 	(*map[c])(NULL, c);
1943 
1944 	/* If rl_done was set by the above call, deal with it here */
1945 	if (rl_done)
1946 		return CC_EOF;
1947 
1948 	return CC_NORM;
1949 }
1950 
1951 int
1952 rl_add_defun(const char *name, Function *fun, int c)
1953 {
1954 	char dest[8];
1955 	if ((size_t)c >= sizeof(map) / sizeof(map[0]) || c < 0)
1956 		return -1;
1957 	map[(unsigned char)c] = fun;
1958 	el_set(e, EL_ADDFN, name, name, rl_bind_wrapper);
1959 	vis(dest, c, VIS_WHITE|VIS_NOSLASH, 0);
1960 	el_set(e, EL_BIND, dest, name, NULL);
1961 	return 0;
1962 }
1963 
1964 void
1965 rl_callback_read_char()
1966 {
1967 	int count = 0, done = 0;
1968 	const char *buf = el_gets(e, &count);
1969 	char *wbuf;
1970 
1971 	if (buf == NULL || count-- <= 0)
1972 		return;
1973 	if (count == 0 && buf[0] == e->el_tty.t_c[TS_IO][C_EOF])
1974 		done = 1;
1975 	if (buf[count] == '\n' || buf[count] == '\r')
1976 		done = 2;
1977 
1978 	if (done && rl_linefunc != NULL) {
1979 		el_set(e, EL_UNBUFFERED, 0);
1980 		if (done == 2) {
1981 		    if ((wbuf = strdup(buf)) != NULL)
1982 			wbuf[count] = '\0';
1983 		} else
1984 			wbuf = NULL;
1985 		(*(void (*)(const char *))rl_linefunc)(wbuf);
1986 		//el_set(e, EL_UNBUFFERED, 1);
1987 	}
1988 }
1989 
1990 void
1991 rl_callback_handler_install(const char *prompt, VCPFunction *linefunc)
1992 {
1993 	if (e == NULL) {
1994 		rl_initialize();
1995 	}
1996 	(void)rl_set_prompt(prompt);
1997 	rl_linefunc = linefunc;
1998 	el_set(e, EL_UNBUFFERED, 1);
1999 }
2000 
2001 void
2002 rl_callback_handler_remove(void)
2003 {
2004 	el_set(e, EL_UNBUFFERED, 0);
2005 	rl_linefunc = NULL;
2006 }
2007 
2008 void
2009 rl_redisplay(void)
2010 {
2011 	char a[2];
2012 	a[0] = e->el_tty.t_c[TS_IO][C_REPRINT];
2013 	a[1] = '\0';
2014 	el_push(e, a);
2015 }
2016 
2017 int
2018 rl_get_previous_history(int count, int key)
2019 {
2020 	char a[2];
2021 	a[0] = key;
2022 	a[1] = '\0';
2023 	while (count--)
2024 		el_push(e, a);
2025 	return 0;
2026 }
2027 
2028 void
2029 /*ARGSUSED*/
2030 rl_prep_terminal(int meta_flag)
2031 {
2032 	el_set(e, EL_PREP_TERM, 1);
2033 }
2034 
2035 void
2036 rl_deprep_terminal(void)
2037 {
2038 	el_set(e, EL_PREP_TERM, 0);
2039 }
2040 
2041 int
2042 rl_read_init_file(const char *s)
2043 {
2044 	return el_source(e, s);
2045 }
2046 
2047 int
2048 rl_parse_and_bind(const char *line)
2049 {
2050 	const char **argv;
2051 	int argc;
2052 	Tokenizer *tok;
2053 
2054 	tok = tok_init(NULL);
2055 	tok_str(tok, line, &argc, &argv);
2056 	argc = el_parse(e, argc, argv);
2057 	tok_end(tok);
2058 	return argc ? 1 : 0;
2059 }
2060 
2061 int
2062 rl_variable_bind(const char *var, const char *value)
2063 {
2064 	/*
2065 	 * The proper return value is undocument, but this is what the
2066 	 * readline source seems to do.
2067 	 */
2068 	return el_set(e, EL_BIND, "", var, value, NULL) == -1 ? 1 : 0;
2069 }
2070 
2071 void
2072 rl_stuff_char(int c)
2073 {
2074 	char buf[2];
2075 
2076 	buf[0] = c;
2077 	buf[1] = '\0';
2078 	el_insertstr(e, buf);
2079 }
2080 
2081 static int
2082 _rl_event_read_char(EditLine *el, wchar_t *wc)
2083 {
2084 	char	ch;
2085 	int	n;
2086 	ssize_t num_read = 0;
2087 
2088 	ch = '\0';
2089 	*wc = L'\0';
2090 	while (rl_event_hook) {
2091 
2092 		(*rl_event_hook)();
2093 
2094 #if defined(FIONREAD)
2095 		if (ioctl(el->el_infd, FIONREAD, &n) == -1)
2096 			return -1;
2097 		if (n)
2098 			num_read = read(el->el_infd, &ch, 1);
2099 		else
2100 			num_read = 0;
2101 #elif defined(F_SETFL) && defined(O_NDELAY)
2102 		if ((n = fcntl(el->el_infd, F_GETFL)) == -1)
2103 			return -1;
2104 		if (fcntl(el->el_infd, F_SETFL, n|O_NDELAY) == -1)
2105 			return -1;
2106 		num_read = read(el->el_infd, &ch, 1);
2107 		if (fcntl(el->el_infd, F_SETFL, n))
2108 			return -1;
2109 #else
2110 		/* not non-blocking, but what you gonna do? */
2111 		num_read = read(el->el_infd, &ch, 1);
2112 		return -1;
2113 #endif
2114 
2115 		if (num_read == -1 && errno == EAGAIN)
2116 			continue;
2117 		if (num_read == 0)
2118 			continue;
2119 		break;
2120 	}
2121 	if (!rl_event_hook)
2122 		el_set(el, EL_GETCFN, EL_BUILTIN_GETCFN);
2123 	*wc = (wchar_t)ch;
2124 	return (int)num_read;
2125 }
2126 
2127 static void
2128 _rl_update_pos(void)
2129 {
2130 	const LineInfo *li = el_line(e);
2131 
2132 	rl_point = (int)(li->cursor - li->buffer);
2133 	rl_end = (int)(li->lastchar - li->buffer);
2134 }
2135 
2136 void
2137 rl_get_screen_size(int *rows, int *cols)
2138 {
2139 	if (rows)
2140 		el_get(e, EL_GETTC, "li", rows);
2141 	if (cols)
2142 		el_get(e, EL_GETTC, "co", cols);
2143 }
2144 
2145 void
2146 rl_set_screen_size(int rows, int cols)
2147 {
2148 	char buf[64];
2149 	(void)snprintf(buf, sizeof(buf), "%d", rows);
2150 	el_set(e, EL_SETTC, "li", buf, NULL);
2151 	(void)snprintf(buf, sizeof(buf), "%d", cols);
2152 	el_set(e, EL_SETTC, "co", buf, NULL);
2153 }
2154 
2155 char **
2156 rl_completion_matches(const char *str, rl_compentry_func_t *fun)
2157 {
2158 	size_t len, max, i, j, min;
2159 	char **list, *match, *a, *b;
2160 
2161 	len = 1;
2162 	max = 10;
2163 	if ((list = reallocarray(NULL, max, sizeof(*list))) == NULL)
2164 		return NULL;
2165 
2166 	while ((match = (*fun)(str, (int)(len - 1))) != NULL) {
2167 		list[len++] = match;
2168 		if (len == max) {
2169 			char **nl;
2170 			max += 10;
2171 			if ((nl = reallocarray(list, max, sizeof(*nl))) == NULL)
2172 				goto out;
2173 			list = nl;
2174 		}
2175 	}
2176 	if (len == 1)
2177 		goto out;
2178 	list[len] = NULL;
2179 	if (len == 2) {
2180 		if ((list[0] = strdup(list[1])) == NULL)
2181 			goto out;
2182 		return list;
2183 	}
2184 	qsort(&list[1], len - 1, sizeof(*list),
2185 	    (int (*)(const void *, const void *)) strcmp);
2186 	min = SIZE_MAX;
2187 	for (i = 1, a = list[i]; i < len - 1; i++, a = b) {
2188 		b = list[i + 1];
2189 		for (j = 0; a[j] && a[j] == b[j]; j++)
2190 			continue;
2191 		if (min > j)
2192 			min = j;
2193 	}
2194 	if (min == 0 && *str) {
2195 		if ((list[0] = strdup(str)) == NULL)
2196 			goto out;
2197 	} else {
2198 		if ((list[0] = malloc(min + 1)) == NULL)
2199 			goto out;
2200 		(void)memcpy(list[0], list[1], min);
2201 		list[0][min] = '\0';
2202 	}
2203 	return list;
2204 
2205 out:
2206 	free(list);
2207 	return NULL;
2208 }
2209 
2210 char *
2211 rl_filename_completion_function (const char *text, int state)
2212 {
2213 	return fn_filename_completion_function(text, state);
2214 }
2215 
2216 void
2217 rl_forced_update_display(void)
2218 {
2219 	el_set(e, EL_REFRESH);
2220 }
2221 
2222 int
2223 _rl_abort_internal(void)
2224 {
2225 	el_beep(e);
2226 	longjmp(topbuf, 1);
2227 	/*NOTREACHED*/
2228 }
2229 
2230 int
2231 _rl_qsort_string_compare(char **s1, char **s2)
2232 {
2233 	return strcoll(*s1, *s2);
2234 }
2235 
2236 HISTORY_STATE *
2237 history_get_history_state(void)
2238 {
2239 	HISTORY_STATE *hs;
2240 
2241 	if ((hs = malloc(sizeof(HISTORY_STATE))) == NULL)
2242 		return NULL;
2243 	hs->length = history_length;
2244 	return hs;
2245 }
2246 
2247 int
2248 /*ARGSUSED*/
2249 rl_kill_text(int from, int to)
2250 {
2251 	return 0;
2252 }
2253 
2254 Keymap
2255 rl_make_bare_keymap(void)
2256 {
2257 	return NULL;
2258 }
2259 
2260 Keymap
2261 rl_get_keymap(void)
2262 {
2263 	return NULL;
2264 }
2265 
2266 void
2267 /*ARGSUSED*/
2268 rl_set_keymap(Keymap k)
2269 {
2270 }
2271 
2272 int
2273 /*ARGSUSED*/
2274 rl_generic_bind(int type, const char * keyseq, const char * data, Keymap k)
2275 {
2276 	return 0;
2277 }
2278 
2279 int
2280 /*ARGSUSED*/
2281 rl_bind_key_in_map(int key, rl_command_func_t *fun, Keymap k)
2282 {
2283 	return 0;
2284 }
2285 
2286 /* unsupported, but needed by python */
2287 void
2288 rl_cleanup_after_signal(void)
2289 {
2290 }
2291 
2292 int
2293 rl_on_new_line(void)
2294 {
2295 	return 0;
2296 }
2297 
2298 int
2299 /*ARGSUSED*/
2300 rl_set_keyboard_input_timeout(int u __attribute__((__unused__)))
2301 {
2302 	return 0;
2303 }
2304