GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.bin/vi/build/../cl/cl_screen.c Lines: 0 161 0.0 %
Date: 2017-11-07 Branches: 0 114 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: cl_screen.c,v 1.28 2017/04/18 01:45:33 deraadt Exp $	*/
2
3
/*-
4
 * Copyright (c) 1993, 1994
5
 *	The Regents of the University of California.  All rights reserved.
6
 * Copyright (c) 1993, 1994, 1995, 1996
7
 *	Keith Bostic.  All rights reserved.
8
 *
9
 * See the LICENSE file for redistribution information.
10
 */
11
12
#include "config.h"
13
14
#include <sys/types.h>
15
#include <sys/queue.h>
16
17
#include <bitstring.h>
18
#include <curses.h>
19
#include <errno.h>
20
#include <signal.h>
21
#include <stdio.h>
22
#include <stdlib.h>
23
#include <string.h>
24
#include <term.h>
25
#include <termios.h>
26
#include <unistd.h>
27
28
#include "../common/common.h"
29
#include "cl.h"
30
31
static int	cl_ex_end(GS *);
32
static int	cl_ex_init(SCR *);
33
static void	cl_freecap(CL_PRIVATE *);
34
static int	cl_vi_end(GS *);
35
static int	cl_vi_init(SCR *);
36
static int	cl_putenv(char *, char *, u_long);
37
38
/*
39
 * cl_screen --
40
 *	Switch screen types.
41
 *
42
 * PUBLIC: int cl_screen(SCR *, u_int32_t);
43
 */
44
int
45
cl_screen(SCR *sp, u_int32_t flags)
46
{
47
	CL_PRIVATE *clp;
48
	GS *gp;
49
50
	gp = sp->gp;
51
	clp = CLP(sp);
52
53
	/* See if the current information is incorrect. */
54
	if (F_ISSET(gp, G_SRESTART)) {
55
		if ((!F_ISSET(sp, SC_SCR_EX | SC_SCR_VI) ||
56
		    resizeterm(O_VAL(sp, O_LINES), O_VAL(sp, O_COLUMNS))) &&
57
		    cl_quit(gp))
58
			return (1);
59
		F_CLR(gp, G_SRESTART);
60
	}
61
62
	/* See if we're already in the right mode. */
63
	if ((LF_ISSET(SC_EX) && F_ISSET(sp, SC_SCR_EX)) ||
64
	    (LF_ISSET(SC_VI) && F_ISSET(sp, SC_SCR_VI)))
65
		return (0);
66
67
	/*
68
	 * Fake leaving ex mode.
69
	 *
70
	 * We don't actually exit ex or vi mode unless forced (e.g. by a window
71
	 * size change).  This is because many curses implementations can't be
72
	 * called twice in a single program.  Plus, it's faster.  If the editor
73
	 * "leaves" vi to enter ex, when it exits ex we'll just fall back into
74
	 * vi.
75
	 */
76
	if (F_ISSET(sp, SC_SCR_EX))
77
		F_CLR(sp, SC_SCR_EX);
78
79
	/*
80
	 * Fake leaving vi mode.
81
	 *
82
	 * Clear out the rest of the screen if we're in the middle of a split
83
	 * screen.  Move to the last line in the current screen -- this makes
84
	 * terminal scrolling happen naturally.  Note: *don't* move past the
85
	 * end of the screen, as there are ex commands (e.g., :read ! cat file)
86
	 * that don't want to.  Don't clear the info line, its contents may be
87
	 * valid, e.g. :file|append.
88
	 */
89
	if (F_ISSET(sp, SC_SCR_VI)) {
90
		F_CLR(sp, SC_SCR_VI);
91
92
		if (TAILQ_NEXT(sp, q)) {
93
			(void)move(RLNO(sp, sp->rows), 0);
94
			clrtobot();
95
		}
96
		(void)move(RLNO(sp, sp->rows) - 1, 0);
97
		refresh();
98
	}
99
100
	/* Enter the requested mode. */
101
	if (LF_ISSET(SC_EX)) {
102
		if (cl_ex_init(sp))
103
			return (1);
104
		F_SET(clp, CL_IN_EX | CL_SCR_EX_INIT);
105
106
		/*
107
		 * If doing an ex screen for ex mode, move to the last line
108
		 * on the screen.
109
		 */
110
		if (F_ISSET(sp, SC_EX) && clp->cup != NULL)
111
			tputs(tgoto(clp->cup,
112
			    0, O_VAL(sp, O_LINES) - 1), 1, cl_putchar);
113
	} else {
114
		if (cl_vi_init(sp))
115
			return (1);
116
		F_CLR(clp, CL_IN_EX);
117
		F_SET(clp, CL_SCR_VI_INIT);
118
	}
119
	return (0);
120
}
121
122
/*
123
 * cl_quit --
124
 *	Shutdown the screens.
125
 *
126
 * PUBLIC: int cl_quit(GS *);
127
 */
128
int
129
cl_quit(GS *gp)
130
{
131
	CL_PRIVATE *clp;
132
	int rval;
133
134
	rval = 0;
135
	clp = GCLP(gp);
136
137
	/*
138
	 * If we weren't really running, ignore it.  This happens if the
139
	 * screen changes size before we've called curses.
140
	 */
141
	if (!F_ISSET(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT))
142
		return (0);
143
144
	/* Clean up the terminal mappings. */
145
	if (cl_term_end(gp))
146
		rval = 1;
147
148
	/* Really leave vi mode. */
149
	if (F_ISSET(clp, CL_STDIN_TTY) &&
150
	    F_ISSET(clp, CL_SCR_VI_INIT) && cl_vi_end(gp))
151
		rval = 1;
152
153
	/* Really leave ex mode. */
154
	if (F_ISSET(clp, CL_STDIN_TTY) &&
155
	    F_ISSET(clp, CL_SCR_EX_INIT) && cl_ex_end(gp))
156
		rval = 1;
157
158
	/*
159
	 * If we were running ex when we quit, or we're using an implementation
160
	 * of curses where endwin() doesn't get this right, restore the original
161
	 * terminal modes.
162
	 *
163
	 * XXX
164
	 * We always do this because it's too hard to figure out what curses
165
	 * implementations get it wrong.  It may discard type-ahead characters
166
	 * from the tty queue.
167
	 */
168
	if (F_ISSET(clp, CL_STDIN_TTY))
169
		(void)tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->orig);
170
171
	F_CLR(clp, CL_SCR_EX_INIT | CL_SCR_VI_INIT);
172
	return (rval);
173
}
174
175
/*
176
 * cl_vi_init --
177
 *	Initialize the curses vi screen.
178
 */
179
static int
180
cl_vi_init(SCR *sp)
181
{
182
	CL_PRIVATE *clp;
183
	char *o_cols, *o_lines, *o_term, *ttype;
184
185
	clp = CLP(sp);
186
187
	/* If already initialized, just set the terminal modes. */
188
	if (F_ISSET(clp, CL_SCR_VI_INIT))
189
		goto fast;
190
191
	/* Curses vi always reads from (and writes to) a terminal. */
192
	if (!F_ISSET(clp, CL_STDIN_TTY) || !isatty(STDOUT_FILENO)) {
193
		msgq(sp, M_ERR,
194
		    "Vi's standard input and output must be a terminal");
195
		return (1);
196
	}
197
198
	/* We'll need a terminal type. */
199
	if (opts_empty(sp, O_TERM, 0))
200
		return (1);
201
	ttype = O_STR(sp, O_TERM);
202
203
	/*
204
	 * XXX
205
	 * Changing the row/column and terminal values is done by putting them
206
	 * into the environment, which is then read by curses.  What this loses
207
	 * in ugliness, it makes up for in stupidity.  We can't simply put the
208
	 * values into the environment ourselves, because in the presence of a
209
	 * kernel mechanism for returning the window size, entering values into
210
	 * the environment will screw up future screen resizing events, e.g. if
211
	 * the user enters a :shell command and then resizes their window.  So,
212
	 * if they weren't already in the environment, we make sure to delete
213
	 * them immediately after setting them.
214
	 *
215
	 * XXX
216
	 * Putting the TERM variable into the environment is necessary, even
217
	 * though we're using newterm() here.  We may be using initscr() as
218
	 * the underlying function.
219
	 */
220
	o_term = getenv("TERM");
221
	cl_putenv("TERM", ttype, 0);
222
	o_lines = getenv("LINES");
223
	cl_putenv("LINES", NULL, (u_long)O_VAL(sp, O_LINES));
224
	o_cols = getenv("COLUMNS");
225
	cl_putenv("COLUMNS", NULL, (u_long)O_VAL(sp, O_COLUMNS));
226
227
	/*
228
	 * The terminal is aways initialized, either in `main`, or by a
229
	 * previous call to newterm(3).
230
	 */
231
	(void)del_curterm(cur_term);
232
233
	/*
234
	 * We don't care about the SCREEN reference returned by newterm, we
235
	 * never have more than one SCREEN at a time.
236
	 */
237
	errno = 0;
238
	if (newterm(ttype, stdout, stdin) == NULL) {
239
		if (errno)
240
			msgq(sp, M_SYSERR, "%s", ttype);
241
		else
242
			msgq(sp, M_ERR, "%s: unknown terminal type", ttype);
243
		return (1);
244
	}
245
246
	if (o_term == NULL)
247
		unsetenv("TERM");
248
	if (o_lines == NULL)
249
		unsetenv("LINES");
250
	if (o_cols == NULL)
251
		unsetenv("COLUMNS");
252
253
	/*
254
	 * XXX
255
	 * Someone got let out alone without adult supervision -- the SunOS
256
	 * newterm resets the signal handlers.  There's a race, but it's not
257
	 * worth closing.
258
	 */
259
	(void)sig_init(sp->gp, sp);
260
261
	/*
262
	 * We use raw mode.  What we want is 8-bit clean, however, signals
263
	 * and flow control should continue to work.  Admittedly, it sounds
264
	 * like cbreak, but it isn't.  Using cbreak() can get you additional
265
	 * things like IEXTEN, which turns on flags like DISCARD and LNEXT.
266
	 *
267
	 * !!!
268
	 * If raw isn't turning off echo and newlines, something's wrong.
269
	 * However, it shouldn't hurt.
270
	 */
271
	noecho();			/* No character echo. */
272
	nonl();				/* No CR/NL translation. */
273
	raw();				/* 8-bit clean. */
274
	idlok(stdscr, 1);		/* Use hardware insert/delete line. */
275
276
	/* Put the cursor keys into application mode. */
277
	(void)keypad(stdscr, TRUE);
278
279
	/*
280
	 * XXX
281
	 * The screen TI sequence just got sent.  See the comment in
282
	 * cl_funcs.c:cl_attr().
283
	 */
284
	clp->ti_te = TI_SENT;
285
286
	/*
287
	 * XXX
288
	 * Historic implementations of curses handled SIGTSTP signals
289
	 * in one of three ways.  They either:
290
	 *
291
	 *	1: Set their own handler, regardless.
292
	 *	2: Did not set a handler if a handler was already installed.
293
	 *	3: Set their own handler, but then called any previously set
294
	 *	   handler after completing their own cleanup.
295
	 *
296
	 * We don't try and figure out which behavior is in place, we force
297
	 * it to SIG_DFL after initializing the curses interface, which means
298
	 * that curses isn't going to take the signal.  Since curses isn't
299
	 * reentrant (i.e., the whole curses SIGTSTP interface is a fantasy),
300
	 * we're doing The Right Thing.
301
	 */
302
	(void)signal(SIGTSTP, SIG_DFL);
303
304
	/*
305
	 * If flow control was on, turn it back on.  Turn signals on.  ISIG
306
	 * turns on VINTR, VQUIT, VDSUSP and VSUSP.   The main curses code
307
	 * already installed a handler for VINTR.  We're going to disable the
308
	 * other three.
309
	 *
310
	 * XXX
311
	 * We want to use ^Y as a vi scrolling command.  If the user has the
312
	 * DSUSP character set to ^Y (common practice) clean it up.  As it's
313
	 * equally possible that the user has VDSUSP set to 'a', we disable
314
	 * it regardless.  It doesn't make much sense to suspend vi at read,
315
	 * so I don't think anyone will care.  Alternatively, we could look
316
	 * it up in the table of legal command characters and turn it off if
317
	 * it matches one.
318
	 *
319
	 * XXX
320
	 * We don't check to see if the user had signals enabled originally.
321
	 * If they didn't, it's unclear what we're supposed to do here, but
322
	 * it's also pretty unlikely.
323
	 */
324
	if (tcgetattr(STDIN_FILENO, &clp->vi_enter)) {
325
		msgq(sp, M_SYSERR, "tcgetattr");
326
		goto err;
327
	}
328
	if (clp->orig.c_iflag & IXON)
329
		clp->vi_enter.c_iflag |= IXON;
330
	if (clp->orig.c_iflag & IXOFF)
331
		clp->vi_enter.c_iflag |= IXOFF;
332
333
	clp->vi_enter.c_lflag |= ISIG;
334
	clp->vi_enter.c_cc[VDSUSP] = _POSIX_VDISABLE;
335
	clp->vi_enter.c_cc[VQUIT] = _POSIX_VDISABLE;
336
	clp->vi_enter.c_cc[VSUSP] = _POSIX_VDISABLE;
337
338
	/*
339
	 * XXX
340
	 * OSF/1 doesn't turn off the <discard>, <literal-next> or <status>
341
	 * characters when curses switches into raw mode.  It should be OK
342
	 * to do it explicitly for everyone.
343
	 */
344
	clp->vi_enter.c_cc[VDISCARD] = _POSIX_VDISABLE;
345
	clp->vi_enter.c_cc[VLNEXT] = _POSIX_VDISABLE;
346
	clp->vi_enter.c_cc[VSTATUS] = _POSIX_VDISABLE;
347
348
	/* Initialize terminal based information. */
349
	if (cl_term_init(sp))
350
		goto err;
351
352
fast:	/* Set the terminal modes. */
353
	if (tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &clp->vi_enter)) {
354
		if (errno == EINTR)
355
			goto fast;
356
		msgq(sp, M_SYSERR, "tcsetattr");
357
err:		(void)cl_vi_end(sp->gp);
358
		return (1);
359
	}
360
	return (0);
361
}
362
363
/*
364
 * cl_vi_end --
365
 *	Shutdown the vi screen.
366
 */
367
static int
368
cl_vi_end(GS *gp)
369
{
370
	CL_PRIVATE *clp;
371
372
	clp = GCLP(gp);
373
374
	/* Restore the cursor keys to normal mode. */
375
	(void)keypad(stdscr, FALSE);
376
377
	/*
378
	 * If we were running vi when we quit, scroll the screen up a single
379
	 * line so we don't lose any information.
380
	 *
381
	 * Move to the bottom of the window (some endwin implementations don't
382
	 * do this for you).
383
	 */
384
	if (!F_ISSET(clp, CL_IN_EX)) {
385
		(void)move(0, 0);
386
		(void)deleteln();
387
		(void)move(LINES - 1, 0);
388
		(void)refresh();
389
	}
390
391
	cl_freecap(clp);
392
393
	/* End curses window. */
394
	(void)endwin();
395
396
	/* Free the SCREEN created by newterm(3). */
397
	delscreen(set_term(NULL));
398
399
	/*
400
	 * XXX
401
	 * The screen TE sequence just got sent.  See the comment in
402
	 * cl_funcs.c:cl_attr().
403
	 */
404
	clp->ti_te = TE_SENT;
405
406
	return (0);
407
}
408
409
/*
410
 * cl_ex_init --
411
 *	Initialize the ex screen.
412
 */
413
static int
414
cl_ex_init(SCR *sp)
415
{
416
	CL_PRIVATE *clp;
417
418
	clp = CLP(sp);
419
420
	/* If already initialized, just set the terminal modes. */
421
	if (F_ISSET(clp, CL_SCR_EX_INIT))
422
		goto fast;
423
424
	/* If not reading from a file, we're done. */
425
	if (!F_ISSET(clp, CL_STDIN_TTY))
426
		return (0);
427
428
	/* Get the ex termcap/terminfo strings. */
429
	(void)cl_getcap(sp, "cup", &clp->cup);
430
	(void)cl_getcap(sp, "smso", &clp->smso);
431
	(void)cl_getcap(sp, "rmso", &clp->rmso);
432
	(void)cl_getcap(sp, "el", &clp->el);
433
	(void)cl_getcap(sp, "cuu1", &clp->cuu1);
434
435
	/* Enter_standout_mode and exit_standout_mode are paired. */
436
	if (clp->smso == NULL || clp->rmso == NULL) {
437
		free(clp->smso);
438
		clp->smso = NULL;
439
		free(clp->rmso);
440
		clp->rmso = NULL;
441
	}
442
443
	/*
444
	 * Turn on canonical mode, with normal input and output processing.
445
	 * Start with the original terminal settings as the user probably
446
	 * had them (including any local extensions) set correctly for the
447
	 * current terminal.
448
	 *
449
	 * !!!
450
	 * We can't get everything that we need portably; for example, ONLCR,
451
	 * mapping <newline> to <carriage-return> on output isn't required
452
	 * by POSIX 1003.1b-1993.  If this turns out to be a problem, then
453
	 * we'll either have to play some games on the mapping, or we'll have
454
	 * to make all ex printf's output \r\n instead of \n.
455
	 */
456
	clp->ex_enter = clp->orig;
457
	clp->ex_enter.c_lflag |=
458
	    ECHO | ECHOCTL | ECHOE | ECHOK | ECHOKE | ICANON | IEXTEN | ISIG;
459
	clp->ex_enter.c_iflag |= ICRNL;
460
	clp->ex_enter.c_oflag |= ONLCR | OPOST;
461
462
fast:	if (tcsetattr(STDIN_FILENO, TCSADRAIN | TCSASOFT, &clp->ex_enter)) {
463
		if (errno == EINTR)
464
			goto fast;
465
		msgq(sp, M_SYSERR, "tcsetattr");
466
		return (1);
467
	}
468
	return (0);
469
}
470
471
/*
472
 * cl_ex_end --
473
 *	Shutdown the ex screen.
474
 */
475
static int
476
cl_ex_end(GS *gp)
477
{
478
	CL_PRIVATE *clp;
479
480
	clp = GCLP(gp);
481
482
	cl_freecap(clp);
483
484
	return (0);
485
}
486
487
/*
488
 * cl_getcap --
489
 *	Retrieve termcap/terminfo strings.
490
 *
491
 * PUBLIC: int cl_getcap(SCR *, char *, char **);
492
 */
493
int
494
cl_getcap(SCR *sp, char *name, char **elementp)
495
{
496
	size_t len;
497
	char *t;
498
499
	if ((t = tigetstr(name)) != NULL &&
500
	    t != (char *)-1 && (len = strlen(t)) != 0) {
501
		MALLOC_RET(sp, *elementp, len + 1);
502
		memmove(*elementp, t, len + 1);
503
	}
504
	return (0);
505
}
506
507
/*
508
 * cl_freecap --
509
 *	Free any allocated termcap/terminfo strings.
510
 */
511
static void
512
cl_freecap(CL_PRIVATE *clp)
513
{
514
	free(clp->el);
515
	clp->el = NULL;
516
	free(clp->cup);
517
	clp->cup = NULL;
518
	free(clp->cuu1);
519
	clp->cuu1 = NULL;
520
	free(clp->rmso);
521
	clp->rmso = NULL;
522
	free(clp->smso);
523
	clp->smso = NULL;
524
}
525
526
/*
527
 * cl_putenv --
528
 *	Put a value into the environment.
529
 */
530
static int
531
cl_putenv(char *name, char *str, u_long value)
532
{
533
	char buf[40];
534
535
	if (str == NULL) {
536
		(void)snprintf(buf, sizeof(buf), "%lu", value);
537
		return (setenv(name, buf, 1));
538
	} else
539
		return (setenv(name, str, 1));
540
}