xref: /freebsd/bin/sh/histedit.c (revision bbd421cdf6d8c6102e6fd3979c5bec21ace3c2e3)
1 /*-
2  * Copyright (c) 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Kenneth Almquist.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)histedit.c	8.2 (Berkeley) 5/4/95";
36 #endif
37 #endif /* not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
40 
41 #include <sys/param.h>
42 #include <sys/stat.h>
43 #include <dirent.h>
44 #include <limits.h>
45 #include <paths.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <unistd.h>
49 /*
50  * Editline and history functions (and glue).
51  */
52 #include "shell.h"
53 #include "parser.h"
54 #include "var.h"
55 #include "options.h"
56 #include "main.h"
57 #include "output.h"
58 #include "mystring.h"
59 #include "builtins.h"
60 #ifndef NO_HISTORY
61 #include "myhistedit.h"
62 #include "error.h"
63 #include "eval.h"
64 #include "memalloc.h"
65 
66 #define MAXHISTLOOPS	4	/* max recursions through fc */
67 #define DEFEDITOR	"ed"	/* default editor *should* be $EDITOR */
68 
69 History *hist;	/* history cookie */
70 EditLine *el;	/* editline cookie */
71 int displayhist;
72 static FILE *el_in, *el_out;
73 
74 static char *fc_replace(const char *, char *, char *);
75 static int not_fcnumber(const char *);
76 static int str_to_event(const char *, int);
77 static int comparator(const void *, const void *, void *);
78 static char **sh_matches(const char *, int, int);
79 static unsigned char sh_complete(EditLine *, int);
80 
81 /*
82  * Set history and editing status.  Called whenever the status may
83  * have changed (figures out what to do).
84  */
85 void
86 histedit(void)
87 {
88 
89 #define editing (Eflag || Vflag)
90 
91 	if (iflag) {
92 		if (!hist) {
93 			/*
94 			 * turn history on
95 			 */
96 			INTOFF;
97 			hist = history_init();
98 			INTON;
99 
100 			if (hist != NULL)
101 				sethistsize(histsizeval());
102 			else
103 				out2fmt_flush("sh: can't initialize history\n");
104 		}
105 		if (editing && !el && isatty(0)) { /* && isatty(2) ??? */
106 			/*
107 			 * turn editing on
108 			 */
109 			char *term;
110 
111 			INTOFF;
112 			if (el_in == NULL)
113 				el_in = fdopen(0, "r");
114 			if (el_out == NULL)
115 				el_out = fdopen(2, "w");
116 			if (el_in == NULL || el_out == NULL)
117 				goto bad;
118 			term = lookupvar("TERM");
119 			if (term)
120 				setenv("TERM", term, 1);
121 			else
122 				unsetenv("TERM");
123 			el = el_init(arg0, el_in, el_out, el_out);
124 			if (el != NULL) {
125 				if (hist)
126 					el_set(el, EL_HIST, history, hist);
127 				el_set(el, EL_PROMPT, getprompt);
128 				el_set(el, EL_ADDFN, "sh-complete",
129 				    "Filename completion",
130 				    sh_complete);
131 			} else {
132 bad:
133 				out2fmt_flush("sh: can't initialize editing\n");
134 			}
135 			INTON;
136 		} else if (!editing && el) {
137 			INTOFF;
138 			el_end(el);
139 			el = NULL;
140 			INTON;
141 		}
142 		if (el) {
143 			if (Vflag)
144 				el_set(el, EL_EDITOR, "vi");
145 			else if (Eflag) {
146 				el_set(el, EL_EDITOR, "emacs");
147 				el_set(el, EL_BIND, "^R", "em-inc-search-prev", NULL);
148 			}
149 			el_set(el, EL_BIND, "^I", "sh-complete", NULL);
150 			el_source(el, NULL);
151 		}
152 	} else {
153 		INTOFF;
154 		if (el) {	/* no editing if not interactive */
155 			el_end(el);
156 			el = NULL;
157 		}
158 		if (hist) {
159 			history_end(hist);
160 			hist = NULL;
161 		}
162 		INTON;
163 	}
164 }
165 
166 
167 void
168 sethistsize(const char *hs)
169 {
170 	int histsize;
171 	HistEvent he;
172 
173 	if (hist != NULL) {
174 		if (hs == NULL || !is_number(hs))
175 			histsize = 100;
176 		else
177 			histsize = atoi(hs);
178 		history(hist, &he, H_SETSIZE, histsize);
179 		history(hist, &he, H_SETUNIQUE, 1);
180 	}
181 }
182 
183 void
184 setterm(const char *term)
185 {
186 	if (rootshell && el != NULL && term != NULL)
187 		el_set(el, EL_TERMINAL, term);
188 }
189 
190 int
191 histcmd(int argc, char **argv __unused)
192 {
193 	int ch;
194 	const char *editor = NULL;
195 	HistEvent he;
196 	int lflg = 0, nflg = 0, rflg = 0, sflg = 0;
197 	int i, retval;
198 	const char *firststr, *laststr;
199 	int first, last, direction;
200 	char *pat = NULL, *repl = NULL;
201 	static int active = 0;
202 	struct jmploc jmploc;
203 	struct jmploc *savehandler;
204 	char editfilestr[PATH_MAX];
205 	char *volatile editfile;
206 	FILE *efp = NULL;
207 	int oldhistnum;
208 
209 	if (hist == NULL)
210 		error("history not active");
211 
212 	if (argc == 1)
213 		error("missing history argument");
214 
215 	while (not_fcnumber(*argptr) && (ch = nextopt("e:lnrs")) != '\0')
216 		switch ((char)ch) {
217 		case 'e':
218 			editor = shoptarg;
219 			break;
220 		case 'l':
221 			lflg = 1;
222 			break;
223 		case 'n':
224 			nflg = 1;
225 			break;
226 		case 'r':
227 			rflg = 1;
228 			break;
229 		case 's':
230 			sflg = 1;
231 			break;
232 		}
233 
234 	savehandler = handler;
235 	/*
236 	 * If executing...
237 	 */
238 	if (lflg == 0 || editor || sflg) {
239 		lflg = 0;	/* ignore */
240 		editfile = NULL;
241 		/*
242 		 * Catch interrupts to reset active counter and
243 		 * cleanup temp files.
244 		 */
245 		if (setjmp(jmploc.loc)) {
246 			active = 0;
247 			if (editfile)
248 				unlink(editfile);
249 			handler = savehandler;
250 			longjmp(handler->loc, 1);
251 		}
252 		handler = &jmploc;
253 		if (++active > MAXHISTLOOPS) {
254 			active = 0;
255 			displayhist = 0;
256 			error("called recursively too many times");
257 		}
258 		/*
259 		 * Set editor.
260 		 */
261 		if (sflg == 0) {
262 			if (editor == NULL &&
263 			    (editor = bltinlookup("FCEDIT", 1)) == NULL &&
264 			    (editor = bltinlookup("EDITOR", 1)) == NULL)
265 				editor = DEFEDITOR;
266 			if (editor[0] == '-' && editor[1] == '\0') {
267 				sflg = 1;	/* no edit */
268 				editor = NULL;
269 			}
270 		}
271 	}
272 
273 	/*
274 	 * If executing, parse [old=new] now
275 	 */
276 	if (lflg == 0 && *argptr != NULL &&
277 	     ((repl = strchr(*argptr, '=')) != NULL)) {
278 		pat = *argptr;
279 		*repl++ = '\0';
280 		argptr++;
281 	}
282 	/*
283 	 * determine [first] and [last]
284 	 */
285 	if (*argptr == NULL) {
286 		firststr = lflg ? "-16" : "-1";
287 		laststr = "-1";
288 	} else if (argptr[1] == NULL) {
289 		firststr = argptr[0];
290 		laststr = lflg ? "-1" : argptr[0];
291 	} else if (argptr[2] == NULL) {
292 		firststr = argptr[0];
293 		laststr = argptr[1];
294 	} else
295 		error("too many arguments");
296 	/*
297 	 * Turn into event numbers.
298 	 */
299 	first = str_to_event(firststr, 0);
300 	last = str_to_event(laststr, 1);
301 
302 	if (rflg) {
303 		i = last;
304 		last = first;
305 		first = i;
306 	}
307 	/*
308 	 * XXX - this should not depend on the event numbers
309 	 * always increasing.  Add sequence numbers or offset
310 	 * to the history element in next (diskbased) release.
311 	 */
312 	direction = first < last ? H_PREV : H_NEXT;
313 
314 	/*
315 	 * If editing, grab a temp file.
316 	 */
317 	if (editor) {
318 		int fd;
319 		INTOFF;		/* easier */
320 		sprintf(editfilestr, "%s/_shXXXXXX", _PATH_TMP);
321 		if ((fd = mkstemp(editfilestr)) < 0)
322 			error("can't create temporary file %s", editfile);
323 		editfile = editfilestr;
324 		if ((efp = fdopen(fd, "w")) == NULL) {
325 			close(fd);
326 			error("Out of space");
327 		}
328 	}
329 
330 	/*
331 	 * Loop through selected history events.  If listing or executing,
332 	 * do it now.  Otherwise, put into temp file and call the editor
333 	 * after.
334 	 *
335 	 * The history interface needs rethinking, as the following
336 	 * convolutions will demonstrate.
337 	 */
338 	history(hist, &he, H_FIRST);
339 	retval = history(hist, &he, H_NEXT_EVENT, first);
340 	for (;retval != -1; retval = history(hist, &he, direction)) {
341 		if (lflg) {
342 			if (!nflg)
343 				out1fmt("%5d ", he.num);
344 			out1str(he.str);
345 		} else {
346 			const char *s = pat ?
347 			   fc_replace(he.str, pat, repl) : he.str;
348 
349 			if (sflg) {
350 				if (displayhist) {
351 					out2str(s);
352 					flushout(out2);
353 				}
354 				evalstring(s, 0);
355 				if (displayhist && hist) {
356 					/*
357 					 *  XXX what about recursive and
358 					 *  relative histnums.
359 					 */
360 					oldhistnum = he.num;
361 					history(hist, &he, H_ENTER, s);
362 					/*
363 					 * XXX H_ENTER moves the internal
364 					 * cursor, set it back to the current
365 					 * entry.
366 					 */
367 					history(hist, &he,
368 					    H_NEXT_EVENT, oldhistnum);
369 				}
370 			} else
371 				fputs(s, efp);
372 		}
373 		/*
374 		 * At end?  (if we were to lose last, we'd sure be
375 		 * messed up).
376 		 */
377 		if (he.num == last)
378 			break;
379 	}
380 	if (editor) {
381 		char *editcmd;
382 
383 		fclose(efp);
384 		INTON;
385 		editcmd = stalloc(strlen(editor) + strlen(editfile) + 2);
386 		sprintf(editcmd, "%s %s", editor, editfile);
387 		evalstring(editcmd, 0);	/* XXX - should use no JC command */
388 		readcmdfile(editfile);	/* XXX - should read back - quick tst */
389 		unlink(editfile);
390 	}
391 
392 	if (lflg == 0 && active > 0)
393 		--active;
394 	if (displayhist)
395 		displayhist = 0;
396 	handler = savehandler;
397 	return 0;
398 }
399 
400 static char *
401 fc_replace(const char *s, char *p, char *r)
402 {
403 	char *dest;
404 	int plen = strlen(p);
405 
406 	STARTSTACKSTR(dest);
407 	while (*s) {
408 		if (*s == *p && strncmp(s, p, plen) == 0) {
409 			STPUTS(r, dest);
410 			s += plen;
411 			*p = '\0';	/* so no more matches */
412 		} else
413 			STPUTC(*s++, dest);
414 	}
415 	STPUTC('\0', dest);
416 	dest = grabstackstr(dest);
417 
418 	return (dest);
419 }
420 
421 static int
422 not_fcnumber(const char *s)
423 {
424 	if (s == NULL)
425 		return (0);
426 	if (*s == '-')
427 		s++;
428 	return (!is_number(s));
429 }
430 
431 static int
432 str_to_event(const char *str, int last)
433 {
434 	HistEvent he;
435 	const char *s = str;
436 	int relative = 0;
437 	int i, retval;
438 
439 	retval = history(hist, &he, H_FIRST);
440 	switch (*s) {
441 	case '-':
442 		relative = 1;
443 		/*FALLTHROUGH*/
444 	case '+':
445 		s++;
446 	}
447 	if (is_number(s)) {
448 		i = atoi(s);
449 		if (relative) {
450 			while (retval != -1 && i--) {
451 				retval = history(hist, &he, H_NEXT);
452 			}
453 			if (retval == -1)
454 				retval = history(hist, &he, H_LAST);
455 		} else {
456 			retval = history(hist, &he, H_NEXT_EVENT, i);
457 			if (retval == -1) {
458 				/*
459 				 * the notion of first and last is
460 				 * backwards to that of the history package
461 				 */
462 				retval = history(hist, &he, last ? H_FIRST : H_LAST);
463 			}
464 		}
465 		if (retval == -1)
466 			error("history number %s not found (internal error)",
467 			       str);
468 	} else {
469 		/*
470 		 * pattern
471 		 */
472 		retval = history(hist, &he, H_PREV_STR, str);
473 		if (retval == -1)
474 			error("history pattern not found: %s", str);
475 	}
476 	return (he.num);
477 }
478 
479 int
480 bindcmd(int argc, char **argv)
481 {
482 	int ret;
483 	FILE *old;
484 	FILE *out;
485 
486 	if (el == NULL)
487 		error("line editing is disabled");
488 
489 	INTOFF;
490 
491 	out = out1fp();
492 	if (out == NULL)
493 		error("Out of space");
494 
495 	el_get(el, EL_GETFP, 1, &old);
496 	el_set(el, EL_SETFP, 1, out);
497 
498 	ret = el_parse(el, argc, __DECONST(const char **, argv));
499 
500 	el_set(el, EL_SETFP, 1, old);
501 
502 	fclose(out);
503 
504 	INTON;
505 
506 	return ret;
507 }
508 
509 #else
510 #include "error.h"
511 
512 int
513 histcmd(int argc __unused, char **argv __unused)
514 {
515 
516 	error("not compiled with history support");
517 	/*NOTREACHED*/
518 	return (0);
519 }
520 
521 int
522 bindcmd(int argc __unused, char **argv __unused)
523 {
524 
525 	error("not compiled with line editing support");
526 	return (0);
527 }
528 #endif
529 
530 /*
531  * Comparator function for qsort(). The use of curpos here is to skip
532  * characters that we already know to compare equal (common prefix).
533  */
534 static int
535 comparator(const void *a, const void *b, void *thunk)
536 {
537 	size_t curpos = (intptr_t)thunk;
538 	return (strcmp(*(char *const *)a + curpos,
539 		*(char *const *)b + curpos));
540 }
541 
542 /*
543  * This function is passed to libedit's fn_complete2(). The library will
544  * use it instead of its standard function that finds matching files in
545  * current directory. If we're at the start of the line, we want to look
546  * for available commands from all paths in $PATH.
547  */
548 static char
549 **sh_matches(const char *text, int start, int end)
550 {
551 	char *free_path = NULL, *path;
552 	const char *dirname;
553 	char **matches = NULL;
554 	size_t i = 0, size = 16, j, k;
555 	size_t curpos = end - start;
556 
557 	if (start > 0 || memchr("/.~", text[0], 3) != NULL)
558 		return (NULL);
559 	if ((free_path = path = strdup(pathval())) == NULL)
560 		goto out;
561 	if ((matches = malloc(size * sizeof(matches[0]))) == NULL)
562 		goto out;
563 	while ((dirname = strsep(&path, ":")) != NULL) {
564 		struct dirent *entry;
565 		DIR *dir;
566 		int dfd;
567 
568 		dir = opendir(dirname[0] == '\0' ? "." : dirname);
569 		if (dir == NULL)
570 			continue;
571 		if ((dfd = dirfd(dir)) == -1) {
572 			closedir(dir);
573 			continue;
574 		}
575 		while ((entry = readdir(dir)) != NULL) {
576 			struct stat statb;
577 			char **rmatches;
578 
579 			if (strncmp(entry->d_name, text, curpos) != 0)
580 				continue;
581 			if (entry->d_type == DT_UNKNOWN || entry->d_type == DT_LNK) {
582 				if (fstatat(dfd, entry->d_name, &statb, 0) == -1)
583 					continue;
584 				if (!S_ISREG(statb.st_mode))
585 					continue;
586 			} else if (entry->d_type != DT_REG)
587 				continue;
588 			matches[++i] = strdup(entry->d_name);
589 			if (i < size - 1)
590 				continue;
591 			size *= 2;
592 			rmatches = reallocarray(matches, size, sizeof(matches[0]));
593 			if (rmatches == NULL) {
594 				closedir(dir);
595 				goto out;
596 			}
597 			matches = rmatches;
598 		}
599 		closedir(dir);
600 	}
601 out:
602 	free(free_path);
603 	/*
604 	 * matches[0] is special: it's not a real matching file name but a common
605 	 * prefix for all matching names. It can't be null, unlike any other
606 	 * element of the array. When strings matches[0] and matches[1] compare
607 	 * equal and matches[2] is null that means to libedit that there is only
608 	 * a single match. It will then replace user input with possibly escaped
609 	 * string in matches[0] which is the reason to copy the full name of the
610 	 * only match.
611 	 */
612 	if (i == 0) {
613 		free(matches);
614 		return (NULL);
615 	} else if (i == 1) {
616 		matches[0] = strdup(matches[1]);
617 		matches[2] = NULL;
618 		if (matches[0] != NULL)
619 			return (matches);
620 	} else
621 		matches[0] = strdup(text);
622 	if (matches[0] == NULL) {
623 		for (j = 1; j <= i; j++)
624 			free(matches[j]);
625 		free(matches);
626 		return (NULL);
627 	}
628 	qsort_s(matches + 1, i, sizeof(matches[0]), comparator,
629 		(void *)(intptr_t)curpos);
630 	for (j = 1, k = 2; k <= i; k++)
631 		if (strcmp(matches[j] + curpos, matches[k] + curpos) == 0)
632 			free(matches[k]);
633 		else
634 			matches[++j] = matches[k];
635 	matches[j + 1] = NULL;
636 	return (matches);
637 }
638 
639 /*
640  * This is passed to el_set(el, EL_ADDFN, ...) so that it's possible to
641  * bind a key (tab by default) to execute the function.
642  */
643 unsigned char
644 sh_complete(EditLine *sel, int ch __unused)
645 {
646 	return (unsigned char)fn_complete2(sel, NULL, sh_matches,
647 		L" \t\n\"\\'`@$><=;|&{(", NULL, NULL, (size_t)100,
648 		NULL, &((int) {0}), NULL, NULL, FN_QUOTE_MATCH);
649 }
650