xref: /freebsd/contrib/nvi/cl/cl_funcs.c (revision 110d525ec6188f3c9dc4f54c4bc1cced2f7184cd)
1 /*-
2  * Copyright (c) 1993, 1994
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 1993, 1994, 1995, 1996
5  *	Keith Bostic.  All rights reserved.
6  *
7  * See the LICENSE file for redistribution information.
8  */
9 
10 #include "config.h"
11 
12 #include <sys/types.h>
13 #include <sys/queue.h>
14 #include <sys/time.h>
15 
16 #include <bitstring.h>
17 #include <ctype.h>
18 #include <signal.h>
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <string.h>
22 #ifdef HAVE_TERM_H
23 #include <term.h>
24 #endif
25 #include <termios.h>
26 #include <unistd.h>
27 
28 #include "../common/common.h"
29 #include "../vi/vi.h"
30 #include "cl.h"
31 
32 static void cl_rdiv(SCR *);
33 
34 static int
addstr4(SCR * sp,void * str,size_t len,int wide)35 addstr4(SCR *sp, void *str, size_t len, int wide)
36 {
37 	CL_PRIVATE *clp;
38 	WINDOW *win;
39 	size_t y, x;
40 	int iv;
41 
42 	clp = CLP(sp);
43 	win = CLSP(sp) ? CLSP(sp) : stdscr;
44 
45 	/*
46 	 * If ex isn't in control, it's the last line of the screen and
47 	 * it's a split screen, use inverse video.
48 	 */
49 	iv = 0;
50 	getyx(win, y, x);
51 	if (!F_ISSET(sp, SC_SCR_EXWROTE) &&
52 	    y == RLNO(sp, LASTLINE(sp)) && IS_SPLIT(sp)) {
53 		iv = 1;
54 		(void)wstandout(win);
55 	}
56 
57 #ifdef USE_WIDECHAR
58 	if (wide) {
59 	    if (waddnwstr(win, str, len) == ERR)
60 		return (1);
61 	} else
62 #endif
63 	    if (waddnstr(win, str, len) == ERR)
64 		    return (1);
65 
66 	if (iv)
67 		(void)wstandend(win);
68 	return (0);
69 }
70 
71 /*
72  * cl_waddstr --
73  *	Add len bytes from the string at the cursor, advancing the cursor.
74  *
75  * PUBLIC: int cl_waddstr(SCR *, const CHAR_T *, size_t);
76  */
77 int
cl_waddstr(SCR * sp,const CHAR_T * str,size_t len)78 cl_waddstr(SCR *sp, const CHAR_T *str, size_t len)
79 {
80 	return addstr4(sp, (void *)str, len, 1);
81 }
82 
83 /*
84  * cl_addstr --
85  *	Add len bytes from the string at the cursor, advancing the cursor.
86  *
87  * PUBLIC: int cl_addstr(SCR *, const char *, size_t);
88  */
89 int
cl_addstr(SCR * sp,const char * str,size_t len)90 cl_addstr(SCR *sp, const char *str, size_t len)
91 {
92 	return addstr4(sp, (void *)str, len, 0);
93 }
94 
95 /*
96  * cl_attr --
97  *	Toggle a screen attribute on/off.
98  *
99  * PUBLIC: int cl_attr(SCR *, scr_attr_t, int);
100  */
101 int
cl_attr(SCR * sp,scr_attr_t attribute,int on)102 cl_attr(SCR *sp, scr_attr_t attribute, int on)
103 {
104 	CL_PRIVATE *clp;
105 	WINDOW *win;
106 
107 	clp = CLP(sp);
108 	win = CLSP(sp) ? CLSP(sp) : stdscr;
109 
110 	switch (attribute) {
111 	case SA_ALTERNATE:
112 	/*
113 	 * !!!
114 	 * There's a major layering violation here.  The problem is that the
115 	 * X11 xterm screen has what's known as an "alternate" screen.  Some
116 	 * xterm termcap/terminfo entries include sequences to switch to/from
117 	 * that alternate screen as part of the ti/te (smcup/rmcup) strings.
118 	 * Vi runs in the alternate screen, so that you are returned to the
119 	 * same screen contents on exit from vi that you had when you entered
120 	 * vi.  Further, when you run :shell, or :!date or similar ex commands,
121 	 * you also see the original screen contents.  This wasn't deliberate
122 	 * on vi's part, it's just that it historically sent terminal init/end
123 	 * sequences at those times, and the addition of the alternate screen
124 	 * sequences to the strings changed the behavior of vi.  The problem
125 	 * caused by this is that we don't want to switch back to the alternate
126 	 * screen while getting a new command from the user, when the user is
127 	 * continuing to enter ex commands, e.g.:
128 	 *
129 	 *	:!date				<<< switch to original screen
130 	 *	[Hit return to continue]	<<< prompt user to continue
131 	 *	:command			<<< get command from user
132 	 *
133 	 * Note that the :command input is a true vi input mode, e.g., input
134 	 * maps and abbreviations are being done.  So, we need to be able to
135 	 * switch back into the vi screen mode, without flashing the screen.
136 	 *
137 	 * To make matters worse, the curses initscr() and endwin() calls will
138 	 * do this automatically -- so, this attribute isn't as controlled by
139 	 * the higher level screen as closely as one might like.
140 	 */
141 	if (on) {
142 		if (clp->ti_te != TI_SENT) {
143 			clp->ti_te = TI_SENT;
144 			if (clp->smcup == NULL)
145 				(void)cl_getcap(sp, "smcup", &clp->smcup);
146 			if (clp->smcup != NULL)
147 				(void)tputs(clp->smcup, 1, cl_putchar);
148 		}
149 	} else
150 		if (clp->ti_te != TE_SENT) {
151 			clp->ti_te = TE_SENT;
152 			if (clp->rmcup == NULL)
153 				(void)cl_getcap(sp, "rmcup", &clp->rmcup);
154 			if (clp->rmcup != NULL)
155 				(void)tputs(clp->rmcup, 1, cl_putchar);
156 			(void)fflush(stdout);
157 		}
158 		(void)fflush(stdout);
159 		break;
160 	case SA_INVERSE:
161 		if (F_ISSET(sp, SC_EX | SC_SCR_EXWROTE)) {
162 			if (clp->smso == NULL)
163 				return (1);
164 			if (on)
165 				(void)tputs(clp->smso, 1, cl_putchar);
166 			else
167 				(void)tputs(clp->rmso, 1, cl_putchar);
168 			(void)fflush(stdout);
169 		} else {
170 			if (on)
171 				(void)wstandout(win);
172 			else
173 				(void)wstandend(win);
174 		}
175 		break;
176 	default:
177 		abort();
178 	}
179 	return (0);
180 }
181 
182 /*
183  * cl_baud --
184  *	Return the baud rate.
185  *
186  * PUBLIC: int cl_baud(SCR *, u_long *);
187  */
188 int
cl_baud(SCR * sp,u_long * ratep)189 cl_baud(SCR *sp, u_long *ratep)
190 {
191 	CL_PRIVATE *clp;
192 
193 	/*
194 	 * XXX
195 	 * There's no portable way to get a "baud rate" -- cfgetospeed(3)
196 	 * returns the value associated with some #define, which we may
197 	 * never have heard of, or which may be a purely local speed.  Vi
198 	 * only cares if it's SLOW (w300), slow (w1200) or fast (w9600).
199 	 * Try and detect the slow ones, and default to fast.
200 	 */
201 	clp = CLP(sp);
202 	switch (cfgetospeed(&clp->orig)) {
203 	case B50:
204 	case B75:
205 	case B110:
206 	case B134:
207 	case B150:
208 	case B200:
209 	case B300:
210 	case B600:
211 		*ratep = 600;
212 		break;
213 	case B1200:
214 		*ratep = 1200;
215 		break;
216 	default:
217 		*ratep = 9600;
218 		break;
219 	}
220 	return (0);
221 }
222 
223 /*
224  * cl_bell --
225  *	Ring the bell/flash the screen.
226  *
227  * PUBLIC: int cl_bell(SCR *);
228  */
229 int
cl_bell(SCR * sp)230 cl_bell(SCR *sp)
231 {
232 	if (F_ISSET(sp, SC_EX | SC_SCR_EXWROTE | SC_SCR_EX))
233 		(void)write(STDOUT_FILENO, "\07", 1);		/* \a */
234 	else {
235 		/*
236 		 * Vi has an edit option which determines if the terminal
237 		 * should be beeped or the screen flashed.
238 		 */
239 		if (O_ISSET(sp, O_FLASH))
240 			(void)flash();
241 		else
242 			(void)beep();
243 	}
244 	return (0);
245 }
246 
247 /*
248  * cl_clrtoeol --
249  *	Clear from the current cursor to the end of the line.
250  *
251  * PUBLIC: int cl_clrtoeol(SCR *);
252  */
253 int
cl_clrtoeol(SCR * sp)254 cl_clrtoeol(SCR *sp)
255 {
256 	WINDOW *win;
257 #if 0
258 	size_t spcnt, y, x;
259 #endif
260 
261 	win = CLSP(sp) ? CLSP(sp) : stdscr;
262 
263 #if 0
264 	if (IS_VSPLIT(sp)) {
265 		/* The cursor must be returned to its original position. */
266 		getyx(win, y, x);
267 		for (spcnt = (sp->coff + sp->cols) - x; spcnt > 0; --spcnt)
268 			(void)waddch(win, ' ');
269 		(void)wmove(win, y, x);
270 		return (0);
271 	} else
272 #endif
273 		return (wclrtoeol(win) == ERR);
274 }
275 
276 /*
277  * cl_cursor --
278  *	Return the current cursor position.
279  *
280  * PUBLIC: int cl_cursor(SCR *, size_t *, size_t *);
281  */
282 int
cl_cursor(SCR * sp,size_t * yp,size_t * xp)283 cl_cursor(SCR *sp, size_t *yp, size_t *xp)
284 {
285 	WINDOW *win;
286 	win = CLSP(sp) ? CLSP(sp) : stdscr;
287 	/*
288 	 * The curses screen support splits a single underlying curses screen
289 	 * into multiple screens to support split screen semantics.  For this
290 	 * reason the returned value must be adjusted to be relative to the
291 	 * current screen, and not absolute.  Screens that implement the split
292 	 * using physically distinct screens won't need this hack.
293 	 */
294 	getyx(win, *yp, *xp);
295 	/*
296 	*yp -= sp->roff;
297 	*xp -= sp->coff;
298 	*/
299 	return (0);
300 }
301 
302 /*
303  * cl_deleteln --
304  *	Delete the current line, scrolling all lines below it.
305  *
306  * PUBLIC: int cl_deleteln(SCR *);
307  */
308 int
cl_deleteln(SCR * sp)309 cl_deleteln(SCR *sp)
310 {
311 	CL_PRIVATE *clp;
312 	WINDOW *win;
313 	size_t y, x;
314 
315 	clp = CLP(sp);
316 	win = CLSP(sp) ? CLSP(sp) : stdscr;
317 
318 	/*
319 	 * This clause is required because the curses screen uses reverse
320 	 * video to delimit split screens.  If the screen does not do this,
321 	 * this code won't be necessary.
322 	 *
323 	 * If the bottom line was in reverse video, rewrite it in normal
324 	 * video before it's scrolled.
325 	 */
326 	if (!F_ISSET(sp, SC_SCR_EXWROTE) && IS_SPLIT(sp)) {
327 		getyx(win, y, x);
328 		mvwchgat(win, RLNO(sp, LASTLINE(sp)), 0, -1, A_NORMAL, 0, NULL);
329 		(void)wmove(win, y, x);
330 	}
331 
332 	/*
333 	 * The bottom line is expected to be blank after this operation,
334 	 * and other screens must support that semantic.
335 	 */
336 	return (wdeleteln(win) == ERR);
337 }
338 
339 /*
340  * cl_discard --
341  *	Discard a screen.
342  *
343  * PUBLIC: int cl_discard(SCR *, SCR **);
344  */
345 int
cl_discard(SCR * discardp,SCR ** acquirep)346 cl_discard(SCR *discardp, SCR **acquirep)
347 {
348 	CL_PRIVATE *clp;
349 	SCR*	tsp;
350 
351 	if (discardp) {
352 	    clp = CLP(discardp);
353 	    F_SET(clp, CL_LAYOUT);
354 
355 	    if (CLSP(discardp)) {
356 		    delwin(CLSP(discardp));
357 		    discardp->cl_private = NULL;
358 	    }
359 	}
360 
361 	/* no screens got a piece; we're done */
362 	if (!acquirep)
363 		return 0;
364 
365 	for (; (tsp = *acquirep) != NULL; ++acquirep) {
366 		clp = CLP(tsp);
367 		F_SET(clp, CL_LAYOUT);
368 
369 		if (CLSP(tsp))
370 			delwin(CLSP(tsp));
371 		tsp->cl_private = subwin(stdscr, tsp->rows, tsp->cols,
372 					   tsp->roff, tsp->coff);
373 	}
374 
375 	/* discardp is going away, acquirep is taking up its space. */
376 	return (0);
377 }
378 
379 /*
380  * cl_ex_adjust --
381  *	Adjust the screen for ex.  This routine is purely for standalone
382  *	ex programs.  All special purpose, all special case.
383  *
384  * PUBLIC: int cl_ex_adjust(SCR *, exadj_t);
385  */
386 int
cl_ex_adjust(SCR * sp,exadj_t action)387 cl_ex_adjust(SCR *sp, exadj_t action)
388 {
389 	CL_PRIVATE *clp;
390 	int cnt;
391 
392 	clp = CLP(sp);
393 	switch (action) {
394 	case EX_TERM_SCROLL:
395 		/* Move the cursor up one line if that's possible. */
396 		if (clp->cuu1 != NULL)
397 			(void)tputs(clp->cuu1, 1, cl_putchar);
398 		else if (clp->cup != NULL)
399 			(void)tputs(tgoto(clp->cup,
400 			    0, LINES - 2), 1, cl_putchar);
401 		else
402 			return (0);
403 		/* FALLTHROUGH */
404 	case EX_TERM_CE:
405 		/* Clear the line. */
406 		if (clp->el != NULL) {
407 			(void)putchar('\r');
408 			(void)tputs(clp->el, 1, cl_putchar);
409 		} else {
410 			/*
411 			 * Historically, ex didn't erase the line, so, if the
412 			 * displayed line was only a single glyph, and <eof>
413 			 * was more than one glyph, the output would not fully
414 			 * overwrite the user's input.  To fix this, output
415 			 * the maxiumum character number of spaces.  Note,
416 			 * this won't help if the user entered extra prompt
417 			 * or <blank> characters before the command character.
418 			 * We'd have to do a lot of work to make that work, and
419 			 * it's almost certainly not worth the effort.
420 			 */
421 			for (cnt = 0; cnt < MAX_CHARACTER_COLUMNS; ++cnt)
422 				(void)putchar('\b');
423 			for (cnt = 0; cnt < MAX_CHARACTER_COLUMNS; ++cnt)
424 				(void)putchar(' ');
425 			(void)putchar('\r');
426 			(void)fflush(stdout);
427 		}
428 		break;
429 	default:
430 		abort();
431 	}
432 	return (0);
433 }
434 
435 /*
436  * cl_insertln --
437  *	Push down the current line, discarding the bottom line.
438  *
439  * PUBLIC: int cl_insertln(SCR *);
440  */
441 int
cl_insertln(SCR * sp)442 cl_insertln(SCR *sp)
443 {
444 	WINDOW *win;
445 	win = CLSP(sp) ? CLSP(sp) : stdscr;
446 	/*
447 	 * The current line is expected to be blank after this operation,
448 	 * and the screen must support that semantic.
449 	 */
450 	return (winsertln(win) == ERR);
451 }
452 
453 /*
454  * cl_keyval --
455  *	Return the value for a special key.
456  *
457  * PUBLIC: int cl_keyval(SCR *, scr_keyval_t, CHAR_T *, int *);
458  */
459 int
cl_keyval(SCR * sp,scr_keyval_t val,CHAR_T * chp,int * dnep)460 cl_keyval(SCR *sp, scr_keyval_t val, CHAR_T *chp, int *dnep)
461 {
462 	CL_PRIVATE *clp;
463 
464 	/*
465 	 * VEOF, VERASE and VKILL are required by POSIX 1003.1-1990,
466 	 * VWERASE is a 4BSD extension.
467 	 */
468 	clp = CLP(sp);
469 	switch (val) {
470 	case KEY_VEOF:
471 		*dnep = (*chp = clp->orig.c_cc[VEOF]) == _POSIX_VDISABLE;
472 		break;
473 	case KEY_VERASE:
474 		*dnep = (*chp = clp->orig.c_cc[VERASE]) == _POSIX_VDISABLE;
475 		break;
476 	case KEY_VKILL:
477 		*dnep = (*chp = clp->orig.c_cc[VKILL]) == _POSIX_VDISABLE;
478 		break;
479 #ifdef VWERASE
480 	case KEY_VWERASE:
481 		*dnep = (*chp = clp->orig.c_cc[VWERASE]) == _POSIX_VDISABLE;
482 		break;
483 #endif
484 	default:
485 		*dnep = 1;
486 		break;
487 	}
488 	return (0);
489 }
490 
491 /*
492  * cl_move --
493  *	Move the cursor.
494  *
495  * PUBLIC: int cl_move(SCR *, size_t, size_t);
496  */
497 int
cl_move(SCR * sp,size_t lno,size_t cno)498 cl_move(SCR *sp, size_t lno, size_t cno)
499 {
500 	WINDOW *win;
501 	win = CLSP(sp) ? CLSP(sp) : stdscr;
502 	/* See the comment in cl_cursor. */
503 	if (wmove(win, RLNO(sp, lno), RCNO(sp, cno)) == ERR) {
504 		msgq(sp, M_ERR, "Error: move: l(%zu + %zu) c(%zu + %zu)",
505 		    lno, sp->roff, cno, sp->coff);
506 		return (1);
507 	}
508 	return (0);
509 }
510 
511 /*
512  * cl_refresh --
513  *	Refresh the screen.
514  *
515  * PUBLIC: int cl_refresh(SCR *, int);
516  */
517 int
cl_refresh(SCR * sp,int repaint)518 cl_refresh(SCR *sp, int repaint)
519 {
520 	GS *gp;
521 	CL_PRIVATE *clp;
522 	WINDOW *win;
523 	SCR *psp, *tsp;
524 	size_t y, x;
525 
526 	gp = sp->gp;
527 	clp = CLP(sp);
528 	win = CLSP(sp) ? CLSP(sp) : stdscr;
529 
530 	/*
531 	 * If we received a killer signal, we're done, there's no point
532 	 * in refreshing the screen.
533 	 */
534 	if (clp->killersig)
535 		return (0);
536 
537 	/*
538 	 * If repaint is set, the editor is telling us that we don't know
539 	 * what's on the screen, so we have to repaint from scratch.
540 	 *
541 	 * If repaint set or the screen layout changed, we need to redraw
542 	 * any lines separating vertically split screens.  If the horizontal
543 	 * offsets are the same, then the split was vertical, and need to
544 	 * draw a dividing line.
545 	 */
546 	if (repaint || F_ISSET(clp, CL_LAYOUT)) {
547 		getyx(stdscr, y, x);
548 		for (psp = sp; psp != NULL; psp = TAILQ_NEXT(psp, q))
549 			for (tsp = TAILQ_NEXT(psp, q); tsp != NULL;
550 			    tsp = TAILQ_NEXT(tsp, q))
551 				if (psp->roff == tsp->roff) {
552 				    if (psp->coff + psp->cols + 1 == tsp->coff)
553 					cl_rdiv(psp);
554 				    else
555 				    if (tsp->coff + tsp->cols + 1 == psp->coff)
556 					cl_rdiv(tsp);
557 				}
558 		(void)wmove(stdscr, y, x);
559 		F_CLR(clp, CL_LAYOUT);
560 	}
561 
562 	/*
563 	 * In the curses library, doing wrefresh(curscr) is okay, but the
564 	 * screen flashes when we then apply the refresh() to bring it up
565 	 * to date.  So, use clearok().
566 	 */
567 	if (repaint)
568 		clearok(curscr, 1);
569 	/*
570 	 * Only do an actual refresh, when this is the focus window,
571 	 * i.e. the one holding the cursor. This assumes that refresh
572 	 * is called for that window after refreshing the others.
573 	 * This prevents the cursor being drawn in the other windows.
574 	 */
575 	return (wnoutrefresh(stdscr) == ERR ||
576 		wnoutrefresh(win) == ERR ||
577 		(sp == clp->focus && doupdate() == ERR));
578 }
579 
580 /*
581  * cl_rdiv --
582  *	Draw a dividing line between two vertically split screens.
583  */
584 static void
cl_rdiv(SCR * sp)585 cl_rdiv(SCR *sp)
586 {
587 #ifdef __NetBSD__
588 	mvvline(sp->roff, sp->cols + sp->coff, '|', sp->rows);
589 #else
590 	mvvline(sp->roff, sp->cols + sp->coff, ACS_VLINE, sp->rows);
591 #endif
592 }
593 
594 /*
595  * cl_rename --
596  *	Rename the file.
597  *
598  * PUBLIC: int cl_rename(SCR *, char *, int);
599  */
600 int
cl_rename(SCR * sp,char * name,int on)601 cl_rename(SCR *sp, char *name, int on)
602 {
603 	GS *gp;
604 	CL_PRIVATE *clp;
605 	FILE *pfp;
606 	char buf[256], *s, *e;
607 	char * wid;
608 	char cmd[64];
609 
610 	gp = sp->gp;
611 	clp = CLP(sp);
612 
613 	/*
614 	 * XXX
615 	 * We can only rename windows for xterm.
616 	 */
617 	if (on) {
618 		clp->focus = sp;
619 		if (!F_ISSET(clp, CL_RENAME_OK) ||
620 		    strncmp(OG_STR(gp, GO_TERM), "xterm", 5))
621 			return (0);
622 
623 		if (clp->oname == NULL && (wid = getenv("WINDOWID"))) {
624 			snprintf(cmd, sizeof(cmd), "xprop -id %s WM_NAME", wid);
625 			if ((pfp = popen(cmd, "r")) == NULL)
626 				goto rename;
627 			if (fgets(buf, sizeof(buf), pfp) == NULL) {
628 				pclose(pfp);
629 				goto rename;
630 			}
631 			pclose(pfp);
632 			if ((s = strchr(buf, '"')) != NULL &&
633 			    (e = strrchr(buf, '"')) != NULL)
634 				clp->oname = strndup(s + 1, e - s - 1);
635 		}
636 
637 rename:		cl_setname(gp, name);
638 
639 		F_SET(clp, CL_RENAME);
640 	} else
641 		if (F_ISSET(clp, CL_RENAME)) {
642 			cl_setname(gp, clp->oname);
643 
644 			F_CLR(clp, CL_RENAME);
645 		}
646 	return (0);
647 }
648 
649 /*
650  * cl_setname --
651  *	Set a X11 icon/window name.
652  *
653  * PUBLIC: void cl_setname(GS *, char *);
654  */
655 void
cl_setname(GS * gp,char * name)656 cl_setname(GS *gp, char *name)
657 {
658 /* X11 xterm escape sequence to rename the icon/window. */
659 #define	XTERM_RENAME	"\033]0;%s\007"
660 
661 	(void)printf(XTERM_RENAME, name == NULL ? OG_STR(gp, GO_TERM) : name);
662 	(void)fflush(stdout);
663 #undef XTERM_RENAME
664 }
665 
666 /*
667  * cl_split --
668  *	Split a screen.
669  *
670  * PUBLIC: int cl_split(SCR *, SCR *);
671  */
672 int
cl_split(SCR * origp,SCR * newp)673 cl_split(SCR *origp, SCR *newp)
674 {
675 	CL_PRIVATE *clp;
676 
677 	clp = CLP(origp);
678 	F_SET(clp, CL_LAYOUT);
679 
680 	if (CLSP(origp))
681 		delwin(CLSP(origp));
682 
683 	origp->cl_private = subwin(stdscr, origp->rows, origp->cols,
684 				     origp->roff, origp->coff);
685 	newp->cl_private = subwin(stdscr, newp->rows, newp->cols,
686 				     newp->roff, newp->coff);
687 
688 	/* origp is the original screen, giving up space to newp. */
689 	return (0);
690 }
691 
692 /*
693  * cl_suspend --
694  *	Suspend a screen.
695  *
696  * PUBLIC: int cl_suspend(SCR *, int *);
697  */
698 int
cl_suspend(SCR * sp,int * allowedp)699 cl_suspend(SCR *sp, int *allowedp)
700 {
701 	struct termios t;
702 	CL_PRIVATE *clp;
703 	WINDOW *win;
704 	GS *gp;
705 	size_t y, x;
706 	int changed;
707 
708 	gp = sp->gp;
709 	clp = CLP(sp);
710 	win = CLSP(sp) ? CLSP(sp) : stdscr;
711 	*allowedp = 1;
712 
713 	/*
714 	 * The ex implementation of this function isn't needed by screens not
715 	 * supporting ex commands that require full terminal canonical mode
716 	 * (e.g. :suspend).
717 	 *
718 	 * The vi implementation of this function isn't needed by screens not
719 	 * supporting vi process suspension, i.e. any screen that isn't backed
720 	 * by a UNIX shell.
721 	 *
722 	 * Setting allowedp to 0 will cause the editor to reject the command.
723 	 */
724 	if (F_ISSET(sp, SC_EX)) {
725 		/* Save the terminal settings, and restore the original ones. */
726 		if (F_ISSET(clp, CL_STDIN_TTY)) {
727 			(void)tcgetattr(STDIN_FILENO, &t);
728 			(void)tcsetattr(STDIN_FILENO,
729 			    TCSASOFT | TCSADRAIN, &clp->orig);
730 		}
731 
732 		/* Stop the process group. */
733 		(void)kill(0, SIGTSTP);
734 
735 		/* Time passes ... */
736 
737 		/* Restore terminal settings. */
738 		if (F_ISSET(clp, CL_STDIN_TTY))
739 			(void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &t);
740 		return (0);
741 	}
742 
743 	/*
744 	 * Move to the lower left-hand corner of the screen.
745 	 *
746 	 * XXX
747 	 * Not sure this is necessary in System V implementations, but it
748 	 * shouldn't hurt.
749 	 */
750 	getyx(win, y, x);
751 	(void)wmove(win, LINES - 1, 0);
752 	(void)wrefresh(win);
753 
754 	/*
755 	 * Temporarily end the screen.  System V introduced a semantic where
756 	 * endwin() could be restarted.  We use it because restarting curses
757 	 * from scratch often fails in System V.  4BSD curses didn't support
758 	 * restarting after endwin(), so we have to do what clean up we can
759 	 * without calling it.
760 	 */
761 	/* Save the terminal settings. */
762 	(void)tcgetattr(STDIN_FILENO, &t);
763 
764 	/* Restore the cursor keys to normal mode. */
765 	(void)keypad(stdscr, FALSE);
766 
767 	/* Restore the window name. */
768 	(void)cl_rename(sp, NULL, 0);
769 
770 	(void)endwin();
771 
772 	/*
773 	 * XXX
774 	 * Restore the original terminal settings.  This is bad -- the
775 	 * reset can cause character loss from the tty queue.  However,
776 	 * we can't call endwin() in BSD curses implementations, and too
777 	 * many System V curses implementations don't get it right.
778 	 */
779 	(void)tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->orig);
780 
781 	/* Stop the process group. */
782 	(void)kill(0, SIGTSTP);
783 
784 	/* Time passes ... */
785 
786 	/*
787 	 * If we received a killer signal, we're done.  Leave everything
788 	 * unchanged.  In addition, the terminal has already been reset
789 	 * correctly, so leave it alone.
790 	 */
791 	if (clp->killersig) {
792 		F_CLR(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT);
793 		return (0);
794 	}
795 
796 	/* Restore terminal settings. */
797 	wrefresh(win);			    /* Needed on SunOs/Solaris ? */
798 	if (F_ISSET(clp, CL_STDIN_TTY))
799 		(void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &t);
800 
801 	/* Set the window name. */
802 	(void)cl_rename(sp, sp->frp->name, 1);
803 
804 	/* Put the cursor keys into application mode. */
805 	(void)keypad(stdscr, TRUE);
806 
807 	/* Refresh and repaint the screen. */
808 	(void)wmove(win, y, x);
809 	(void)cl_refresh(sp, 1);
810 
811 	/* If the screen changed size, set the SIGWINCH bit. */
812 	if (cl_ssize(sp, 1, NULL, NULL, &changed))
813 		return (1);
814 	if (changed)
815 		F_SET(CLP(sp), CL_SIGWINCH);
816 
817 	return (0);
818 }
819 
820 /*
821  * cl_usage --
822  *	Print out the curses usage messages.
823  *
824  * PUBLIC: void cl_usage(void);
825  */
826 void
cl_usage(void)827 cl_usage(void)
828 {
829 #define	USAGE "\
830 usage: ex [-eFRrSsv] [-c command] [-t tag] [-w size] [file ...]\n\
831 usage: vi [-eFlRrSv] [-c command] [-t tag] [-w size] [file ...]\n"
832 	(void)fprintf(stderr, "%s", USAGE);
833 #undef	USAGE
834 }
835 
836 #ifdef DEBUG
837 /*
838  * gdbrefresh --
839  *	Stub routine so can flush out curses screen changes using gdb.
840  */
841 static int
842 	__attribute__((unused))
gdbrefresh(void)843 gdbrefresh(void)
844 {
845 	refresh();
846 	return (0);		/* XXX Convince gdb to run it. */
847 }
848 #endif
849