xref: /netbsd-src/bin/sh/histedit.c (revision c42dbd0ed2e61fe6eda8590caa852ccf34719964)
1 /*	$NetBSD: histedit.c,v 1.66 2023/04/07 10:34:13 kre Exp $	*/
2 
3 /*-
4  * Copyright (c) 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Kenneth Almquist.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)histedit.c	8.2 (Berkeley) 5/4/95";
39 #else
40 __RCSID("$NetBSD: histedit.c,v 1.66 2023/04/07 10:34:13 kre Exp $");
41 #endif
42 #endif /* not lint */
43 
44 #include <sys/param.h>
45 #include <sys/stat.h>
46 #include <dirent.h>
47 #include <paths.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <unistd.h>
51 /*
52  * Editline and history functions (and glue).
53  */
54 #include "shell.h"
55 #include "parser.h"
56 #include "var.h"
57 #include "options.h"
58 #include "builtins.h"
59 #include "main.h"
60 #include "output.h"
61 #include "mystring.h"
62 #include "myhistedit.h"
63 #include "error.h"
64 #include "alias.h"
65 #ifndef SMALL
66 #include "eval.h"
67 #include "memalloc.h"
68 #include "show.h"
69 
70 #define MAXHISTLOOPS	4	/* max recursions through fc */
71 #define DEFEDITOR	"ed"	/* default editor *should* be $EDITOR */
72 
73 History *hist;	/* history cookie */
74 EditLine *el;	/* editline cookie */
75 int displayhist;
76 static FILE *el_in, *el_out;
77 static int curpos;
78 
79 #ifdef DEBUG
80 extern FILE *tracefile;
81 #endif
82 
83 static const char *fc_replace(const char *, char *, char *);
84 static int not_fcnumber(const char *);
85 static int str_to_event(const char *, int);
86 static int comparator(const void *, const void *);
87 static char **sh_matches(const char *, int, int);
88 static unsigned char sh_complete(EditLine *, int);
89 
90 /*
91  * Set history and editing status.  Called whenever the status may
92  * have changed (figures out what to do).
93  */
94 void
95 histedit(void)
96 {
97 	FILE *el_err;
98 
99 #define editing (Eflag || Vflag)
100 
101 	CTRACE(DBG_HISTORY, ("histedit: %cE%cV %sinteractive\n",
102 	    Eflag ? '-' : '+',  Vflag ? '-' : '+', iflag ? "" : "not "));
103 
104 	if (iflag == 1) {
105 		if (!hist) {
106 			/*
107 			 * turn history on
108 			 */
109 			INTOFF;
110 			hist = history_init();
111 			INTON;
112 
113 			if (hist != NULL)
114 				sethistsize(histsizeval());
115 			else
116 				out2str("sh: can't initialize history\n");
117 		}
118 		if (editing && !el && isatty(0)) { /* && isatty(2) ??? */
119 			/*
120 			 * turn editing on
121 			 */
122 			char *term;
123 
124 			INTOFF;
125 			if (el_in == NULL)
126 				el_in = fdopen(0, "r");
127 			if (el_out == NULL)
128 				el_out = fdopen(2, "w");
129 			if (el_in == NULL || el_out == NULL)
130 				goto bad;
131 			el_err = el_out;
132 #if DEBUG
133 			if (tracefile)
134 				el_err = tracefile;
135 #endif
136 			/*
137 			 * This odd piece of code doesn't affect the shell
138 			 * at all, the environment modified here is the
139 			 * stuff accessed via "environ" (the incoming
140 			 * environment to the shell) which is only ever
141 			 * touched at sh startup time (long before we get
142 			 * here) and ignored thereafter.
143 			 *
144 			 * But libedit calls getenv() to discover TERM
145 			 * and that searches the "environ" environment,
146 			 * not the shell's internal variable data struct,
147 			 * so we need to make sure that TERM in there is
148 			 * correct.
149 			 *
150 			 * This sequence copies TERM from the shell into
151 			 * the old "environ" environment.
152 			 */
153 			term = lookupvar("TERM");
154 			if (term)
155 				setenv("TERM", term, 1);
156 			else
157 				unsetenv("TERM");
158 			el = el_init("sh", el_in, el_out, el_err);
159 			VTRACE(DBG_HISTORY, ("el_init() %sed\n",
160 			    el != NULL ? "succeed" : "fail"));
161 			if (el != NULL) {
162 				if (hist)
163 					el_set(el, EL_HIST, history, hist);
164 
165 				set_prompt_lit(lookupvar("PSlit"));
166 				el_set(el, EL_SIGNAL, 1);
167 				el_set(el, EL_SAFEREAD, 1);
168 				el_set(el, EL_ALIAS_TEXT, alias_text, NULL);
169 				el_set(el, EL_ADDFN, "rl-complete",
170 				    "ReadLine compatible completion function",
171 				    sh_complete);
172 			} else {
173 bad:
174 				out2str("sh: can't initialize editing\n");
175 			}
176 			INTON;
177 		} else if (!editing && el) {
178 			INTOFF;
179 			el_end(el);
180 			el = NULL;
181 			VTRACE(DBG_HISTORY, ("line editing disabled\n"));
182 			INTON;
183 		}
184 		if (el) {
185 			INTOFF;
186 			if (Vflag)
187 				el_set(el, EL_EDITOR, "vi");
188 			else if (Eflag)
189 				el_set(el, EL_EDITOR, "emacs");
190 			VTRACE(DBG_HISTORY, ("reading $EDITRC\n"));
191 			el_source(el, lookupvar("EDITRC"));
192 			el_set(el, EL_BIND, "^I",
193 			    tabcomplete ? "rl-complete" : "ed-insert", NULL);
194 			INTON;
195 		}
196 	} else {
197 		INTOFF;
198 		if (el) {	/* no editing if not interactive */
199 			el_end(el);
200 			el = NULL;
201 		}
202 		if (hist) {
203 			history_end(hist);
204 			hist = NULL;
205 		}
206 		INTON;
207 		VTRACE(DBG_HISTORY, ("line editing & history disabled\n"));
208 	}
209 }
210 
211 void
212 set_prompt_lit(const char *lit_ch)
213 {
214 	wchar_t wc;
215 
216 	if (!(iflag && editing && el))
217 		return;
218 
219 	if (lit_ch == NULL) {
220 		el_set(el, EL_PROMPT, getprompt);
221 		return;
222 	}
223 
224 	mbtowc(&wc, NULL, 1);		/* state init */
225 
226 	INTOFF;
227 	if (mbtowc(&wc, lit_ch, strlen(lit_ch)) <= 0)
228 		el_set(el, EL_PROMPT, getprompt);
229 	else
230 		el_set(el, EL_PROMPT_ESC, getprompt, (int)wc);
231 	INTON;
232 }
233 
234 void
235 set_editrc(const char *fname)
236 {
237 	INTOFF;
238 	if (iflag && editing && el)
239 		el_source(el, fname);
240 	INTON;
241 }
242 
243 void
244 sethistsize(const char *hs)
245 {
246 	int histsize;
247 	HistEvent he;
248 
249 	if (hist != NULL) {
250 		if (hs == NULL || *hs == '\0' || *hs == '-' ||
251 		   (histsize = number(hs)) < 0)
252 			histsize = 100;
253 		INTOFF;
254 		history(hist, &he, H_SETSIZE, histsize);
255 		history(hist, &he, H_SETUNIQUE, 1);
256 		INTON;
257 	}
258 }
259 
260 void
261 setterm(const char *term)
262 {
263 	INTOFF;
264 	if (el != NULL && term != NULL)
265 		if (el_set(el, EL_TERMINAL, term) != 0) {
266 			outfmt(out2, "sh: Can't set terminal type %s\n", term);
267 			outfmt(out2, "sh: Using dumb terminal settings.\n");
268 		}
269 	INTON;
270 }
271 
272 int
273 inputrc(int argc, char **argv)
274 {
275 	CTRACE(DBG_HISTORY, ("inputrc (%d arg%s)", argc-1, argc==2?"":"s"));
276 	if (argc != 2) {
277 		CTRACE(DBG_HISTORY, (" -- bad\n"));
278 		out2str("usage: inputrc file\n");
279 		return 1;
280 	}
281 	CTRACE(DBG_HISTORY, (" file: \"%s\"\n", argv[1]));
282 	if (el != NULL) {
283 		INTOFF;
284 		if (el_source(el, argv[1])) {
285 			INTON;
286 			out2str("inputrc: failed\n");
287 			return 1;
288 		}
289 		INTON;
290 		return 0;
291 	} else {
292 		out2str("sh: inputrc ignored, not editing\n");
293 		return 1;
294 	}
295 }
296 
297 /*
298  *  This command is provided since POSIX decided to standardize
299  *  the Korn shell fc command.  Oh well...
300  */
301 int
302 histcmd(volatile int argc, char ** volatile argv)
303 {
304 	int ch;
305 	const char * volatile editor = NULL;
306 	HistEvent he;
307 	volatile int lflg = 0, nflg = 0, rflg = 0, sflg = 0;
308 	int i, retval;
309 	const char *firststr, *laststr;
310 	int first, last, direction;
311 	char * volatile pat = NULL, * volatile repl;	/* ksh "fc old=new" crap */
312 	static int active = 0;
313 	struct jmploc jmploc;
314 	struct jmploc *volatile savehandler;
315 	char editfile[MAXPATHLEN + 1];
316 	FILE * volatile efp;
317 #ifdef __GNUC__
318 	repl = NULL;	/* XXX gcc4 */
319 	efp = NULL;	/* XXX gcc4 */
320 #endif
321 
322 	if (hist == NULL)
323 		error("history not active");
324 
325 	CTRACE(DBG_HISTORY, ("histcmd (fc) %d arg%s\n", argc, argc==1?"":"s"));
326 	if (argc == 1)
327 		error("missing history argument");
328 
329 	optreset = 1; optind = 1; /* initialize getopt */
330 	while (not_fcnumber(argv[optind]) &&
331 	      (ch = getopt(argc, argv, ":e:lnrs")) != -1)
332 		switch ((char)ch) {
333 		case 'e':
334 			editor = optarg;
335 			VTRACE(DBG_HISTORY, ("histcmd -e %s\n", editor));
336 			break;
337 		case 'l':
338 			lflg = 1;
339 			VTRACE(DBG_HISTORY, ("histcmd -l\n"));
340 			break;
341 		case 'n':
342 			nflg = 1;
343 			VTRACE(DBG_HISTORY, ("histcmd -n\n"));
344 			break;
345 		case 'r':
346 			rflg = 1;
347 			VTRACE(DBG_HISTORY, ("histcmd -r\n"));
348 			break;
349 		case 's':
350 			sflg = 1;
351 			VTRACE(DBG_HISTORY, ("histcmd -s\n"));
352 			break;
353 		case ':':
354 			error("option -%c expects argument", optopt);
355 			/* NOTREACHED */
356 		case '?':
357 		default:
358 			error("unknown option: -%c", optopt);
359 			/* NOTREACHED */
360 		}
361 	argc -= optind, argv += optind;
362 
363 	/*
364 	 * If executing...
365 	 */
366 	if (lflg == 0 || editor || sflg) {
367 		lflg = 0;	/* ignore */
368 		editfile[0] = '\0';
369 		/*
370 		 * Catch interrupts to reset active counter and
371 		 * cleanup temp files.
372 		 */
373 		savehandler = handler;
374 		if (setjmp(jmploc.loc)) {
375 			active = 0;
376 			if (*editfile) {
377 				VTRACE(DBG_HISTORY,
378 				    ("histcmd err jump unlink temp \"%s\"\n",
379 				    *editfile));
380 				unlink(editfile);
381 			}
382 			handler = savehandler;
383 			longjmp(handler->loc, 1);
384 		}
385 		handler = &jmploc;
386 		VTRACE(DBG_HISTORY, ("histcmd was active %d (++)\n", active));
387 		if (++active > MAXHISTLOOPS) {
388 			active = 0;
389 			displayhist = 0;
390 			error("called recursively too many times");
391 		}
392 		/*
393 		 * Set editor.
394 		 */
395 		if (sflg == 0) {
396 			if (editor == NULL &&
397 			    (editor = bltinlookup("FCEDIT", 1)) == NULL &&
398 			    (editor = bltinlookup("EDITOR", 1)) == NULL)
399 				editor = DEFEDITOR;
400 			if (editor[0] == '-' && editor[1] == '\0') {
401 				sflg = 1;	/* no edit */
402 				editor = NULL;
403 			}
404 			VTRACE(DBG_HISTORY, ("histcmd using %s as editor\n",
405 			    editor == NULL ? "-nothing-" : editor));
406 		}
407 	}
408 
409 	/*
410 	 * If executing, parse [old=new] now
411 	 */
412 	if (lflg == 0 && argc > 0 &&
413 	     ((repl = strchr(argv[0], '=')) != NULL)) {
414 		pat = argv[0];
415 		*repl++ = '\0';
416 		argc--, argv++;
417 		VTRACE(DBG_HISTORY, ("histcmd replace old=\"%s\" new=\"%s\""
418 		    " (%d args)\n", pat, repl, argc));
419 	}
420 
421 	/*
422 	 * If -s is specified, accept only one operand
423 	 */
424 	if (sflg && argc >= 2)
425 		error("too many args");
426 
427 	/*
428 	 * determine [first] and [last]
429 	 */
430 	switch (argc) {
431 	case 0:
432 		firststr = lflg ? "-16" : "-1";
433 		laststr = "-1";
434 		break;
435 	case 1:
436 		firststr = argv[0];
437 		laststr = lflg ? "-1" : argv[0];
438 		break;
439 	case 2:
440 		firststr = argv[0];
441 		laststr = argv[1];
442 		break;
443 	default:
444 		error("too many args");
445 		/* NOTREACHED */
446 	}
447 	/*
448 	 * Turn into event numbers.
449 	 */
450 	first = str_to_event(firststr, 0);
451 	last = str_to_event(laststr, 1);
452 
453 	if (rflg) {
454 		i = last;
455 		last = first;
456 		first = i;
457 	}
458 	VTRACE(DBG_HISTORY, ("histcmd%s first=\"%s\" (#%d) last=\"%s\" (#%d)\n",
459 	    rflg ? " reversed" : "", rflg ? laststr : firststr, first,
460 	    rflg ? firststr : laststr, last));
461 
462 	/*
463 	 * XXX - this should not depend on the event numbers
464 	 * always increasing.  Add sequence numbers or offset
465 	 * to the history element in next (diskbased) release.
466 	 */
467 	direction = first < last ? H_PREV : H_NEXT;
468 
469 	/*
470 	 * If editing, grab a temp file.
471 	 */
472 	if (editor) {
473 		int fd;
474 		INTOFF;		/* easier */
475 		snprintf(editfile, sizeof(editfile), "%s_shXXXXXX", _PATH_TMP);
476 		if ((fd = mkstemp(editfile)) < 0)
477 			error("can't create temporary file %s", editfile);
478 		if ((efp = fdopen(fd, "w")) == NULL) {
479 			close(fd);
480 			error("can't allocate stdio buffer for temp");
481 		}
482 		VTRACE(DBG_HISTORY, ("histcmd created \"%s\" for edit buffer"
483 		    " fd=%d\n", editfile, fd));
484 	}
485 
486 	/*
487 	 * Loop through selected history events.  If listing or executing,
488 	 * do it now.  Otherwise, put into temp file and call the editor
489 	 * after.
490 	 *
491 	 * The history interface needs rethinking, as the following
492 	 * convolutions will demonstrate.
493 	 */
494 	history(hist, &he, H_FIRST);
495 	retval = history(hist, &he, H_NEXT_EVENT, first);
496 	for (;retval != -1; retval = history(hist, &he, direction)) {
497 		if (lflg) {
498 			if (!nflg)
499 				out1fmt("%5d ", he.num);
500 			out1str(he.str);
501 		} else {
502 			const char *s = pat ?
503 			   fc_replace(he.str, pat, repl) : he.str;
504 
505 			if (sflg) {
506 				VTRACE(DBG_HISTORY, ("histcmd -s \"%s\"\n", s));
507 				if (displayhist) {
508 					out2str(s);
509 				}
510 
511 				evalstring(strcpy(stalloc(strlen(s) + 1), s), 0);
512 				if (displayhist && hist) {
513 					/*
514 					 *  XXX what about recursive and
515 					 *  relative histnums.
516 					 */
517 					history(hist, &he, H_ENTER, s);
518 				}
519 
520 				break;
521 			} else
522 				fputs(s, efp);
523 		}
524 		/*
525 		 * At end?  (if we were to lose last, we'd sure be
526 		 * messed up).
527 		 */
528 		if (he.num == last)
529 			break;
530 	}
531 	if (editor) {
532 		char *editcmd;
533 		size_t cmdlen;
534 
535 		fclose(efp);
536 		cmdlen = strlen(editor) + strlen(editfile) + 2;
537 		editcmd = stalloc(cmdlen);
538 		snprintf(editcmd, cmdlen, "%s %s", editor, editfile);
539 		VTRACE(DBG_HISTORY, ("histcmd editing: \"%s\"\n", editcmd));
540 		evalstring(editcmd, 0);	/* XXX - should use no JC command */
541 		stunalloc(editcmd);
542 		VTRACE(DBG_HISTORY, ("histcmd read cmds from %s\n", editfile));
543 		readcmdfile(editfile);	/* XXX - should read back - quick tst */
544 		VTRACE(DBG_HISTORY, ("histcmd unlink %s\n", editfile));
545 		unlink(editfile);
546 		INTON;
547 	}
548 
549 	if (lflg == 0 && active > 0)
550 		--active;
551 	if (displayhist)
552 		displayhist = 0;
553 	return 0;
554 }
555 
556 static const char *
557 fc_replace(const char *s, char *p, char *r)
558 {
559 	char *dest;
560 	int plen = strlen(p);
561 
562 	VTRACE(DBG_HISTORY, ("histcmd s/%s/%s/ in \"%s\" -> ", p, r, s));
563 	STARTSTACKSTR(dest);
564 	while (*s) {
565 		if (*s == *p && strncmp(s, p, plen) == 0) {
566 			while (*r)
567 				STPUTC(*r++, dest);
568 			s += plen;
569 			*p = '\0';	/* so no more matches */
570 		} else
571 			STPUTC(*s++, dest);
572 	}
573 	STACKSTRNUL(dest);
574 	dest = grabstackstr(dest);
575 	VTRACE(DBG_HISTORY, ("\"%s\"\n", dest));
576 
577 	return dest;
578 }
579 
580 
581 /*
582  * Comparator function for qsort(). The use of curpos here is to skip
583  * characters that we already know to compare equal (common prefix).
584  */
585 static int
586 comparator(const void *a, const void *b)
587 {
588 	return strcmp(*(char *const *)a + curpos,
589 		*(char *const *)b + curpos);
590 }
591 
592 /*
593  * This function is passed to libedit's fn_complete(). The library will
594  * use it instead of its standard function to find matches, which
595  * searches for files in current directory. If we're at the start of the
596  * line, we want to look for available commands from all paths in $PATH.
597  */
598 static char
599 **sh_matches(const char *text, int start, int end)
600 {
601 	char *free_path = NULL, *dirname, *path;
602 	char **matches = NULL;
603 	size_t i = 0, size = 16;
604 
605 	if (start > 0)
606 		return NULL;
607 	curpos = end - start;
608 	if ((free_path = path = strdup(pathval())) == NULL)
609 		goto out;
610 	if ((matches = malloc(size * sizeof(matches[0]))) == NULL)
611 		goto out;
612 	while ((dirname = strsep(&path, ":")) != NULL) {
613 		struct dirent *entry;
614 		DIR *dir;
615 		int dfd;
616 
617 		if ((dir = opendir(dirname)) == NULL)
618 			continue;
619 		if ((dfd = dirfd(dir)) == -1)
620 			continue;
621 		while ((entry = readdir(dir)) != NULL) {
622 			struct stat statb;
623 
624 			if (strncmp(entry->d_name, text, curpos) != 0)
625 				continue;
626 			if (entry->d_type == DT_UNKNOWN || entry->d_type == DT_LNK) {
627 				if (fstatat(dfd, entry->d_name, &statb, 0) == -1)
628 					continue;
629 				if (!S_ISREG(statb.st_mode))
630 					continue;
631 			} else if (entry->d_type != DT_REG)
632 				continue;
633 			if (++i >= size - 1) {
634 				size *= 2;
635 				if (reallocarr(&matches, size,
636 				    sizeof(*matches)))
637 				{
638 					closedir(dir);
639 					goto out;
640 				}
641 			}
642 			matches[i] = strdup(entry->d_name);
643 		}
644 		closedir(dir);
645 	}
646 out:
647 	free(free_path);
648 	if (i == 0) {
649 		free(matches);
650 		return NULL;
651 	}
652 	if (i == 1) {
653 		matches[0] = strdup(matches[1]);
654 		matches[i + 1] = NULL;
655 	} else {
656 		size_t j, k;
657 
658 		qsort(matches + 1, i, sizeof(matches[0]), comparator);
659 		for (j = 1, k = 2; k <= i; k++)
660 			if (strcmp(matches[j] + curpos, matches[k] + curpos)
661 			    == 0)
662 				free(matches[k]);
663 			else
664 				matches[++j] = matches[k];
665 		matches[0] = strdup(text);
666 		matches[j + 1] = NULL;
667 	}
668 	return matches;
669 }
670 
671 /*
672  * This is passed to el_set(el, EL_ADDFN, ...) so that it's possible to
673  * bind a key (tab by default) to execute the function.
674  */
675 unsigned char
676 sh_complete(EditLine *sel, int ch __unused)
677 {
678 	return (unsigned char)fn_complete2(sel, NULL, sh_matches,
679 		L" \t\n\"\\'`@$><=;|&{(", NULL, NULL, (size_t)100,
680 		NULL, &((int) {0}), NULL, NULL, FN_QUOTE_MATCH);
681 }
682 
683 static int
684 not_fcnumber(const char *s)
685 {
686 	if (s == NULL)
687 		return 0;
688         if (*s == '-')
689                 s++;
690 	return !is_number(s);
691 }
692 
693 static int
694 str_to_event(const char *str, int last)
695 {
696 	HistEvent he;
697 	const char *s = str;
698 	int relative = 0;
699 	int i, retval;
700 
701 	retval = history(hist, &he, H_FIRST);
702 	switch (*s) {
703 	case '-':
704 		relative = 1;
705 		/*FALLTHROUGH*/
706 	case '+':
707 		s++;
708 	}
709 	if (is_number(s)) {
710 		i = number(s);
711 		if (relative) {
712 			while (retval != -1 && i--) {
713 				retval = history(hist, &he, H_NEXT);
714 			}
715 			if (retval == -1)
716 				retval = history(hist, &he, H_LAST);
717 		} else {
718 			retval = history(hist, &he, H_NEXT_EVENT, i);
719 			if (retval == -1) {
720 				/*
721 				 * the notion of first and last is
722 				 * backwards to that of the history package
723 				 */
724 				retval = history(hist, &he,
725 						last ? H_FIRST : H_LAST);
726 			}
727 		}
728 		if (retval == -1)
729 			error("history number %s not found (internal error)",
730 			       str);
731 	} else {
732 		/*
733 		 * pattern
734 		 */
735 		retval = history(hist, &he, H_PREV_STR, str);
736 		if (retval == -1)
737 			error("history pattern not found: %s", str);
738 	}
739 	return he.num;
740 }
741 #else
742 int
743 histcmd(int argc, char **argv)
744 {
745 	error("not compiled with history support");
746 	/* NOTREACHED */
747 }
748 int
749 inputrc(int argc, char **argv)
750 {
751 	error("not compiled with history support");
752 	/* NOTREACHED */
753 }
754 #endif
755