xref: /netbsd-src/external/bsd/nvi/dist/common/key.c (revision 2f698edb5c1cb2dcd9e762b0abb50c41dde8b6b7)
1 /*	$NetBSD: key.c,v 1.4 2014/01/26 21:43:45 christos Exp $ */
2 /*-
3  * Copyright (c) 1991, 1993, 1994
4  *	The Regents of the University of California.  All rights reserved.
5  * Copyright (c) 1991, 1993, 1994, 1995, 1996
6  *	Keith Bostic.  All rights reserved.
7  *
8  * See the LICENSE file for redistribution information.
9  */
10 
11 #include "config.h"
12 
13 #include <sys/cdefs.h>
14 #if 0
15 #ifndef lint
16 static const char sccsid[] = "Id: key.c,v 10.48 2001/06/25 15:19:10 skimo Exp  (Berkeley) Date: 2001/06/25 15:19:10 ";
17 #endif /* not lint */
18 #else
19 __RCSID("$NetBSD: key.c,v 1.4 2014/01/26 21:43:45 christos Exp $");
20 #endif
21 
22 #include <sys/types.h>
23 #include <sys/queue.h>
24 #include <sys/time.h>
25 
26 #include <bitstring.h>
27 #include <ctype.h>
28 #include <errno.h>
29 #include <limits.h>
30 #include <locale.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35 
36 #include "common.h"
37 #include "../vi/vi.h"
38 
39 static int	v_event_append __P((SCR *, EVENT *));
40 static int	v_event_grow __P((SCR *, int));
41 static int	v_key_cmp __P((const void *, const void *));
42 static void	v_keyval __P((SCR *, int, scr_keyval_t));
43 static void	v_sync __P((SCR *, int));
44 
45 /*
46  * !!!
47  * Historic vi always used:
48  *
49  *	^D: autoindent deletion
50  *	^H: last character deletion
51  *	^W: last word deletion
52  *	^Q: quote the next character (if not used in flow control).
53  *	^V: quote the next character
54  *
55  * regardless of the user's choices for these characters.  The user's erase
56  * and kill characters worked in addition to these characters.  Nvi wires
57  * down the above characters, but in addition permits the VEOF, VERASE, VKILL
58  * and VWERASE characters described by the user's termios structure.
59  *
60  * Ex was not consistent with this scheme, as it historically ran in tty
61  * cooked mode.  This meant that the scroll command and autoindent erase
62  * characters were mapped to the user's EOF character, and the character
63  * and word deletion characters were the user's tty character and word
64  * deletion characters.  This implementation makes it all consistent, as
65  * described above for vi.
66  *
67  * !!!
68  * This means that all screens share a special key set.
69  */
70 KEYLIST keylist[] = {
71 	{K_BACKSLASH,	  '\\'},	/*  \ */
72 	{K_CARAT,	   '^'},	/*  ^ */
73 	{K_CNTRLD,	'\004'},	/* ^D */
74 	{K_CNTRLR,	'\022'},	/* ^R */
75 	{K_CNTRLT,	'\024'},	/* ^T */
76 	{K_CNTRLZ,	'\032'},	/* ^Z */
77 	{K_COLON,	   ':'},	/*  : */
78 	{K_CR,		  '\r'},	/* \r */
79 	{K_ESCAPE,	'\033'},	/* ^[ */
80 	{K_FORMFEED,	  '\f'},	/* \f */
81 	{K_HEXCHAR,	'\030'},	/* ^X */
82 	{K_NL,		  '\n'},	/* \n */
83 	{K_RIGHTBRACE,	   '}'},	/*  } */
84 	{K_RIGHTPAREN,	   ')'},	/*  ) */
85 	{K_TAB,		  '\t'},	/* \t */
86 	{K_VERASE,	  '\b'},	/* \b */
87 	{K_VKILL,	'\025'},	/* ^U */
88 	{K_VLNEXT,	'\021'},	/* ^Q */
89 	{K_VLNEXT,	'\026'},	/* ^V */
90 	{K_VWERASE,	'\027'},	/* ^W */
91 	{K_ZERO,	   '0'},	/*  0 */
92 
93 #define	ADDITIONAL_CHARACTERS	4
94 	{K_NOTUSED, 0},			/* VEOF, VERASE, VKILL, VWERASE */
95 	{K_NOTUSED, 0},
96 	{K_NOTUSED, 0},
97 	{K_NOTUSED, 0},
98 };
99 static int nkeylist =
100     (sizeof(keylist) / sizeof(keylist[0])) - ADDITIONAL_CHARACTERS;
101 
102 /*
103  * v_key_init --
104  *	Initialize the special key lookup table.
105  *
106  * PUBLIC: int v_key_init __P((SCR *));
107  */
108 int
v_key_init(SCR * sp)109 v_key_init(SCR *sp)
110 {
111 	int ch;
112 	GS *gp;
113 	KEYLIST *kp;
114 	int cnt;
115 
116 	gp = sp->gp;
117 
118 	/*
119 	 * XXX
120 	 * 8-bit only, for now.  Recompilation should get you any 8-bit
121 	 * character set, as long as nul isn't a character.
122 	 */
123 	(void)setlocale(LC_ALL, "");
124 #if __linux__
125 	/*
126 	 * In libc 4.5.26, setlocale(LC_ALL, ""), doesn't setup the table
127 	 * for ctype(3c) correctly.  This bug is fixed in libc 4.6.x.
128 	 *
129 	 * This code works around this problem for libc 4.5.x users.
130 	 * Note that this code is harmless if you're using libc 4.6.x.
131 	 */
132 	(void)setlocale(LC_CTYPE, "");
133 #endif
134 	v_key_ilookup(sp);
135 
136 	v_keyval(sp, K_CNTRLD, KEY_VEOF);
137 	v_keyval(sp, K_VERASE, KEY_VERASE);
138 	v_keyval(sp, K_VKILL, KEY_VKILL);
139 	v_keyval(sp, K_VWERASE, KEY_VWERASE);
140 
141 	/* Sort the special key list. */
142 	qsort(keylist, nkeylist, sizeof(keylist[0]), v_key_cmp);
143 
144 	/* Initialize the fast lookup table. */
145 	for (kp = keylist, cnt = nkeylist; cnt--; ++kp)
146 		gp->special_key[kp->ch] = kp->value;
147 
148 	/* Find a non-printable character to use as a message separator. */
149 	for (ch = 1; ch <= UCHAR_MAX; ++ch)
150 		if (!isprint(ch)) {
151 			gp->noprint = ch;
152 			break;
153 		}
154 	if (ch != gp->noprint) {
155 		msgq(sp, M_ERR, "079|No non-printable character found");
156 		return (1);
157 	}
158 	return (0);
159 }
160 
161 /*
162  * v_keyval --
163  *	Set key values.
164  *
165  * We've left some open slots in the keylist table, and if these values exist,
166  * we put them into place.  Note, they may reset (or duplicate) values already
167  * in the table, so we check for that first.
168  */
169 static void
v_keyval(SCR * sp,int val,scr_keyval_t name)170 v_keyval(SCR *sp, int val, scr_keyval_t name)
171 {
172 	KEYLIST *kp;
173 	CHAR_T ch;
174 	int dne;
175 
176 	/* Get the key's value from the screen. */
177 	if (sp->gp->scr_keyval(sp, name, &ch, &dne))
178 		return;
179 	if (dne)
180 		return;
181 
182 	/* Check for duplication. */
183 	for (kp = keylist; kp->value != K_NOTUSED; ++kp)
184 		if (kp->ch == ch) {
185 			kp->value = val;
186 			return;
187 		}
188 
189 	/* Add a new entry. */
190 	if (kp->value == K_NOTUSED) {
191 		keylist[nkeylist].ch = ch;
192 		keylist[nkeylist].value = val;
193 		++nkeylist;
194 	}
195 }
196 
197 /*
198  * v_key_ilookup --
199  *	Build the fast-lookup key display array.
200  *
201  * PUBLIC: void v_key_ilookup __P((SCR *));
202  */
203 void
v_key_ilookup(SCR * sp)204 v_key_ilookup(SCR *sp)
205 {
206 	UCHAR_T ch;
207 	unsigned char *p, *t;
208 	GS *gp;
209 	size_t len;
210 
211 	for (gp = sp->gp, ch = 0;; ++ch) {
212 		for (p = gp->cname[ch].name, t = v_key_name(sp, ch),
213 		    len = gp->cname[ch].len = sp->clen; len--;)
214 			*p++ = *t++;
215 		if (ch == MAX_FAST_KEY)
216 			break;
217 	}
218 }
219 
220 /*
221  * v_key_len --
222  *	Return the length of the string that will display the key.
223  *	This routine is the backup for the KEY_LEN() macro.
224  *
225  * PUBLIC: size_t v_key_len __P((SCR *, ARG_CHAR_T));
226  */
227 size_t
v_key_len(SCR * sp,ARG_CHAR_T ch)228 v_key_len(SCR *sp, ARG_CHAR_T ch)
229 {
230 	(void)v_key_name(sp, ch);
231 	return (sp->clen);
232 }
233 
234 /*
235  * v_key_name --
236  *	Return the string that will display the key.  This routine
237  *	is the backup for the KEY_NAME() macro.
238  *
239  * PUBLIC: u_char *v_key_name __P((SCR *, ARG_CHAR_T));
240  */
241 u_char *
v_key_name(SCR * sp,ARG_CHAR_T ach)242 v_key_name(SCR *sp, ARG_CHAR_T ach)
243 {
244 	static const char hexdigit[] = "0123456789abcdef";
245 	static const char octdigit[] = "01234567";
246 	int ch;
247 	size_t len, i;
248 	const char *chp;
249 
250 	if (INTISWIDE(ach))
251 		goto vis;
252 	ch = (unsigned char)ach;
253 
254 	/* See if the character was explicitly declared printable or not. */
255 	if ((chp = O_STR(sp, O_PRINT)) != NULL)
256 		for (; *chp != '\0'; ++chp)
257 			if (*chp == ch)
258 				goto pr;
259 	if ((chp = O_STR(sp, O_NOPRINT)) != NULL)
260 		for (; *chp != '\0'; ++chp)
261 			if (*chp == ch)
262 				goto nopr;
263 
264 	/*
265 	 * Historical (ARPA standard) mappings.  Printable characters are left
266 	 * alone.  Control characters less than 0x20 are represented as '^'
267 	 * followed by the character offset from the '@' character in the ASCII
268 	 * character set.  Del (0x7f) is represented as '^' followed by '?'.
269 	 *
270 	 * XXX
271 	 * The following code depends on the current locale being identical to
272 	 * the ASCII map from 0x40 to 0x5f (since 0x1f + 0x40 == 0x5f).  I'm
273 	 * told that this is a reasonable assumption...
274 	 *
275 	 * XXX
276 	 * This code will only work with CHAR_T's that are multiples of 8-bit
277 	 * bytes.
278 	 *
279 	 * XXX
280 	 * NB: There's an assumption here that all printable characters take
281 	 * up a single column on the screen.  This is not always correct.
282 	 */
283 	if (isprint(ch)) {
284 pr:		sp->cname[0] = ch;
285 		len = 1;
286 		goto done;
287 	}
288 nopr:	if (iscntrl(ch) && (ch < 0x20 || ch == 0x7f)) {
289 		sp->cname[0] = '^';
290 		sp->cname[1] = ch == 0x7f ? '?' : '@' + ch;
291 		len = 2;
292 		goto done;
293 	}
294 vis:	for (i = 1; i <= sizeof(CHAR_T); ++i)
295 		if ((ach >> i * CHAR_BIT) == 0)
296 			break;
297 	ch = (ach >> --i * CHAR_BIT) & UCHAR_MAX;
298 	if (O_ISSET(sp, O_OCTAL)) {
299 		sp->cname[0] = '\\';
300 		sp->cname[1] = octdigit[(ch & 0300) >> 6];
301 		sp->cname[2] = octdigit[(ch &  070) >> 3];
302 		sp->cname[3] = octdigit[ ch &   07      ];
303 	} else {
304 		sp->cname[0] = '\\';
305 		sp->cname[1] = 'x';
306 		sp->cname[2] = hexdigit[(ch & 0xf0) >> 4];
307 		sp->cname[3] = hexdigit[ ch & 0x0f      ];
308 	}
309 	len = 4;
310 done:	sp->cname[sp->clen = len] = '\0';
311 	return (sp->cname);
312 }
313 
314 /*
315  * v_key_val --
316  *	Fill in the value for a key.  This routine is the backup
317  *	for the KEY_VAL() macro.
318  *
319  * PUBLIC: e_key_t v_key_val __P((SCR *, ARG_CHAR_T));
320  */
321 e_key_t
v_key_val(SCR * sp,ARG_CHAR_T ch)322 v_key_val(SCR *sp, ARG_CHAR_T ch)
323 {
324 	KEYLIST k, *kp;
325 
326 	k.ch = ch;
327 	kp = bsearch(&k, keylist, nkeylist, sizeof(keylist[0]), v_key_cmp);
328 	return (kp == NULL ? K_NOTUSED : kp->value);
329 }
330 
331 /*
332  * v_event_push --
333  *	Push events/keys onto the front of the buffer.
334  *
335  * There is a single input buffer in ex/vi.  Characters are put onto the
336  * end of the buffer by the terminal input routines, and pushed onto the
337  * front of the buffer by various other functions in ex/vi.  Each key has
338  * an associated flag value, which indicates if it has already been quoted,
339  * and if it is the result of a mapping or an abbreviation.
340  *
341  * PUBLIC: int v_event_push __P((SCR *, EVENT *, const CHAR_T *, size_t, u_int));
342  */
343 int
v_event_push(SCR * sp,EVENT * p_evp,const CHAR_T * p_s,size_t nitems,u_int flags)344 v_event_push(SCR *sp, EVENT *p_evp, const CHAR_T *p_s, size_t nitems, u_int flags)
345 
346 	             			/* Push event. */
347 	            			/* Push characters. */
348 	              			/* Number of items to push. */
349 	            			/* CH_* flags. */
350 {
351 	EVENT *evp;
352 	WIN *wp;
353 	size_t total;
354 
355 	/* If we have room, stuff the items into the buffer. */
356 	wp = sp->wp;
357 	if (nitems <= wp->i_next ||
358 	    (wp->i_event != NULL && wp->i_cnt == 0 && nitems <= wp->i_nelem)) {
359 		if (wp->i_cnt != 0)
360 			wp->i_next -= nitems;
361 		goto copy;
362 	}
363 
364 	/*
365 	 * If there are currently items in the queue, shift them up,
366 	 * leaving some extra room.  Get enough space plus a little
367 	 * extra.
368 	 */
369 #define	TERM_PUSH_SHIFT	30
370 	total = wp->i_cnt + wp->i_next + nitems + TERM_PUSH_SHIFT;
371 	if (total >= wp->i_nelem && v_event_grow(sp, MAX(total, 64)))
372 		return (1);
373 	if (wp->i_cnt)
374 		MEMMOVE(wp->i_event + TERM_PUSH_SHIFT + nitems,
375 		    wp->i_event + wp->i_next, wp->i_cnt);
376 	wp->i_next = TERM_PUSH_SHIFT;
377 
378 	/* Put the new items into the queue. */
379 copy:	wp->i_cnt += nitems;
380 	for (evp = wp->i_event + wp->i_next; nitems--; ++evp) {
381 		if (p_evp != NULL)
382 			*evp = *p_evp++;
383 		else {
384 			evp->e_event = E_CHARACTER;
385 			evp->e_c = *p_s++;
386 			evp->e_value = KEY_VAL(sp, evp->e_c);
387 			FL_INIT(evp->e_flags, flags);
388 		}
389 	}
390 	return (0);
391 }
392 
393 /*
394  * v_event_append --
395  *	Append events onto the tail of the buffer.
396  */
397 static int
v_event_append(SCR * sp,EVENT * argp)398 v_event_append(SCR *sp, EVENT *argp)
399 {
400 	CHAR_T *s;			/* Characters. */
401 	EVENT *evp;
402 	WIN *wp;
403 	size_t nevents;			/* Number of events. */
404 
405 	/* Grow the buffer as necessary. */
406 	nevents = argp->e_event == E_STRING ? argp->e_len : 1;
407 	wp = sp->wp;
408 	if (wp->i_event == NULL ||
409 	    nevents > wp->i_nelem - (wp->i_next + wp->i_cnt))
410 		v_event_grow(sp, MAX(nevents, 64));
411 	evp = wp->i_event + wp->i_next + wp->i_cnt;
412 	wp->i_cnt += nevents;
413 
414 	/* Transform strings of characters into single events. */
415 	if (argp->e_event == E_STRING)
416 		for (s = argp->e_csp; nevents--; ++evp) {
417 			evp->e_event = E_CHARACTER;
418 			evp->e_c = *s++;
419 			evp->e_value = KEY_VAL(sp, evp->e_c);
420 			evp->e_flags = 0;
421 		}
422 	else
423 		*evp = *argp;
424 	return (0);
425 }
426 
427 /* Remove events from the queue. */
428 #define	QREM(len) {							\
429 	if ((wp->i_cnt -= len) == 0)					\
430 		wp->i_next = 0;						\
431 	else								\
432 		wp->i_next += len;					\
433 }
434 
435 /*
436  * v_event_get --
437  *	Return the next event.
438  *
439  * !!!
440  * The flag EC_NODIGIT probably needs some explanation.  First, the idea of
441  * mapping keys is that one or more keystrokes act like a function key.
442  * What's going on is that vi is reading a number, and the character following
443  * the number may or may not be mapped (EC_MAPCOMMAND).  For example, if the
444  * user is entering the z command, a valid command is "z40+", and we don't want
445  * to map the '+', i.e. if '+' is mapped to "xxx", we don't want to change it
446  * into "z40xxx".  However, if the user enters "35x", we want to put all of the
447  * characters through the mapping code.
448  *
449  * Historical practice is a bit muddled here.  (Surprise!)  It always permitted
450  * mapping digits as long as they weren't the first character of the map, e.g.
451  * ":map ^A1 xxx" was okay.  It also permitted the mapping of the digits 1-9
452  * (the digit 0 was a special case as it doesn't indicate the start of a count)
453  * as the first character of the map, but then ignored those mappings.  While
454  * it's probably stupid to map digits, vi isn't your mother.
455  *
456  * The way this works is that the EC_MAPNODIGIT causes term_key to return the
457  * end-of-digit without "looking" at the next character, i.e. leaving it as the
458  * user entered it.  Presumably, the next term_key call will tell us how the
459  * user wants it handled.
460  *
461  * There is one more complication.  Users might map keys to digits, and, as
462  * it's described above, the commands:
463  *
464  *	:map g 1G
465  *	d2g
466  *
467  * would return the keys "d2<end-of-digits>1G", when the user probably wanted
468  * "d21<end-of-digits>G".  So, if a map starts off with a digit we continue as
469  * before, otherwise, we pretend we haven't mapped the character, and return
470  * <end-of-digits>.
471  *
472  * Now that that's out of the way, let's talk about Energizer Bunny macros.
473  * It's easy to create macros that expand to a loop, e.g. map x 3x.  It's
474  * fairly easy to detect this example, because it's all internal to term_key.
475  * If we're expanding a macro and it gets big enough, at some point we can
476  * assume it's looping and kill it.  The examples that are tough are the ones
477  * where the parser is involved, e.g. map x "ayyx"byy.  We do an expansion
478  * on 'x', and get "ayyx"byy.  We then return the first 4 characters, and then
479  * find the looping macro again.  There is no way that we can detect this
480  * without doing a full parse of the command, because the character that might
481  * cause the loop (in this case 'x') may be a literal character, e.g. the map
482  * map x "ayy"xyy"byy is perfectly legal and won't cause a loop.
483  *
484  * Historic vi tried to detect looping macros by disallowing obvious cases in
485  * the map command, maps that that ended with the same letter as they started
486  * (which wrongly disallowed "map x 'x"), and detecting macros that expanded
487  * too many times before keys were returned to the command parser.  It didn't
488  * get many (most?) of the tricky cases right, however, and it was certainly
489  * possible to create macros that ran forever.  And, even if it did figure out
490  * what was going on, the user was usually tossed into ex mode.  Finally, any
491  * changes made before vi realized that the macro was recursing were left in
492  * place.  We recover gracefully, but the only recourse the user has in an
493  * infinite macro loop is to interrupt.
494  *
495  * !!!
496  * It is historic practice that mapping characters to themselves as the first
497  * part of the mapped string was legal, and did not cause infinite loops, i.e.
498  * ":map! { {^M^T" and ":map n nz." were known to work.  The initial, matching
499  * characters were returned instead of being remapped.
500  *
501  * !!!
502  * It is also historic practice that the macro "map ] ]]^" caused a single ]
503  * keypress to behave as the command ]] (the ^ got the map past the vi check
504  * for "tail recursion").  Conversely, the mapping "map n nn^" went recursive.
505  * What happened was that, in the historic vi, maps were expanded as the keys
506  * were retrieved, but not all at once and not centrally.  So, the keypress ]
507  * pushed ]]^ on the stack, and then the first ] from the stack was passed to
508  * the ]] command code.  The ]] command then retrieved a key without entering
509  * the mapping code.  This could bite us anytime a user has a map that depends
510  * on secondary keys NOT being mapped.  I can't see any possible way to make
511  * this work in here without the complete abandonment of Rationality Itself.
512  *
513  * XXX
514  * The final issue is recovery.  It would be possible to undo all of the work
515  * that was done by the macro if we entered a record into the log so that we
516  * knew when the macro started, and, in fact, this might be worth doing at some
517  * point.  Given that this might make the log grow unacceptably (consider that
518  * cursor keys are done with maps), for now we leave any changes made in place.
519  *
520  * PUBLIC: int v_event_get __P((SCR *, EVENT *, int, u_int32_t));
521  */
522 int
v_event_get(SCR * sp,EVENT * argp,int timeout,u_int32_t flags)523 v_event_get(SCR *sp, EVENT *argp, int timeout, u_int32_t flags)
524 {
525 	EVENT *evp, ev;
526 	GS *gp;
527 	SEQ *qp;
528 	int init_nomap, ispartial, istimeout, remap_cnt;
529 	WIN *wp;
530 
531 	gp = sp->gp;
532 	wp = sp->wp;
533 
534 	/* If simply checking for interrupts, argp may be NULL. */
535 	if (argp == NULL)
536 		argp = &ev;
537 
538 retry:	istimeout = remap_cnt = 0;
539 
540 	/*
541 	 * If the queue isn't empty and we're timing out for characters,
542 	 * return immediately.
543 	 */
544 	if (wp->i_cnt != 0 && LF_ISSET(EC_TIMEOUT))
545 		return (0);
546 
547 	/*
548 	 * If the queue is empty, we're checking for interrupts, or we're
549 	 * timing out for characters, get more events.
550 	 */
551 	if (wp->i_cnt == 0 || LF_ISSET(EC_INTERRUPT | EC_TIMEOUT)) {
552 		/*
553 		 * If we're reading new characters, check any scripting
554 		 * windows for input.
555 		 */
556 		if (F_ISSET(gp, G_SCRWIN) && sscr_input(sp))
557 			return (1);
558 loop:		if (gp->scr_event(sp, argp,
559 		    LF_ISSET(EC_INTERRUPT | EC_QUOTED | EC_RAW), timeout))
560 			return (1);
561 		switch (argp->e_event) {
562 		case E_ERR:
563 		case E_SIGHUP:
564 		case E_SIGTERM:
565 			/*
566 			 * Fatal conditions cause the file to be synced to
567 			 * disk immediately.
568 			 */
569 			v_sync(sp, RCV_ENDSESSION | RCV_PRESERVE |
570 			    (argp->e_event == E_SIGTERM ? 0: RCV_EMAIL));
571 			return (1);
572 		case E_TIMEOUT:
573 			istimeout = 1;
574 			break;
575 		case E_INTERRUPT:
576 			/* Set the global interrupt flag. */
577 			F_SET(sp->gp, G_INTERRUPTED);
578 
579 			/*
580 			 * If the caller was interested in interrupts, return
581 			 * immediately.
582 			 */
583 			if (LF_ISSET(EC_INTERRUPT))
584 				return (0);
585 			goto append;
586 		default:
587 append:			if (v_event_append(sp, argp))
588 				return (1);
589 			break;
590 		}
591 	}
592 
593 	/*
594 	 * If the caller was only interested in interrupts or timeouts, return
595 	 * immediately.  (We may have gotten characters, and that's okay, they
596 	 * were queued up for later use.)
597 	 */
598 	if (LF_ISSET(EC_INTERRUPT | EC_TIMEOUT))
599 		return (0);
600 
601 newmap:	evp = &wp->i_event[wp->i_next];
602 
603 	/*
604 	 * If the next event in the queue isn't a character event, return
605 	 * it, we're done.
606 	 */
607 	if (evp->e_event != E_CHARACTER) {
608 		*argp = *evp;
609 		QREM(1);
610 		return (0);
611 	}
612 
613 	/*
614 	 * If the key isn't mappable because:
615 	 *
616 	 *	+ ... the timeout has expired
617 	 *	+ ... it's not a mappable key
618 	 *	+ ... neither the command or input map flags are set
619 	 *	+ ... there are no maps that can apply to it
620 	 *
621 	 * return it forthwith.
622 	 */
623 	if (istimeout || FL_ISSET(evp->e_flags, CH_NOMAP) ||
624 	    !LF_ISSET(EC_MAPCOMMAND | EC_MAPINPUT) ||
625 	    ((evp->e_c & ~MAX_BIT_SEQ) == 0 &&
626 	    !bit_test(gp->seqb, evp->e_c)))
627 		goto nomap;
628 
629 	/* Search the map. */
630 	qp = seq_find(sp, NULL, evp, NULL, wp->i_cnt,
631 	    LF_ISSET(EC_MAPCOMMAND) ? SEQ_COMMAND : SEQ_INPUT, &ispartial);
632 
633 	/*
634 	 * If get a partial match, get more characters and retry the map.
635 	 * If time out without further characters, return the characters
636 	 * unmapped.
637 	 *
638 	 * !!!
639 	 * <escape> characters are a problem.  Cursor keys start with <escape>
640 	 * characters, so there's almost always a map in place that begins with
641 	 * an <escape> character.  If we timeout <escape> keys in the same way
642 	 * that we timeout other keys, the user will get a noticeable pause as
643 	 * they enter <escape> to terminate input mode.  If key timeout is set
644 	 * for a slow link, users will get an even longer pause.  Nvi used to
645 	 * simply timeout <escape> characters at 1/10th of a second, but this
646 	 * loses over PPP links where the latency is greater than 100Ms.
647 	 */
648 	if (ispartial) {
649 		if (O_ISSET(sp, O_TIMEOUT))
650 			timeout = (evp->e_value == K_ESCAPE ?
651 			    O_VAL(sp, O_ESCAPETIME) :
652 			    O_VAL(sp, O_KEYTIME)) * 100;
653 		else
654 			timeout = 0;
655 		goto loop;
656 	}
657 
658 	/* If no map, return the character. */
659 	if (qp == NULL) {
660 nomap:		if (!ISDIGIT(evp->e_c) && LF_ISSET(EC_MAPNODIGIT))
661 			goto not_digit;
662 		*argp = *evp;
663 		QREM(1);
664 		return (0);
665 	}
666 
667 	/*
668 	 * If looking for the end of a digit string, and the first character
669 	 * of the map is it, pretend we haven't seen the character.
670 	 */
671 	if (LF_ISSET(EC_MAPNODIGIT) &&
672 	    qp->output != NULL && !ISDIGIT(qp->output[0])) {
673 not_digit:	argp->e_c = CH_NOT_DIGIT;
674 		argp->e_value = K_NOTUSED;
675 		argp->e_event = E_CHARACTER;
676 		FL_INIT(argp->e_flags, 0);
677 		return (0);
678 	}
679 
680 	/* Find out if the initial segments are identical. */
681 	init_nomap = !e_memcmp(qp->output, &wp->i_event[wp->i_next], qp->ilen);
682 
683 	/* Delete the mapped characters from the queue. */
684 	QREM(qp->ilen);
685 
686 	/* If keys mapped to nothing, go get more. */
687 	if (qp->output == NULL)
688 		goto retry;
689 
690 	/* If remapping characters... */
691 	if (O_ISSET(sp, O_REMAP)) {
692 		/*
693 		 * Periodically check for interrupts.  Always check the first
694 		 * time through, because it's possible to set up a map that
695 		 * will return a character every time, but will expand to more,
696 		 * e.g. "map! a aaaa" will always return a 'a', but we'll never
697 		 * get anywhere useful.
698 		 */
699 		if ((++remap_cnt == 1 || remap_cnt % 10 == 0) &&
700 		    (gp->scr_event(sp, &ev,
701 		    EC_INTERRUPT, 0) || ev.e_event == E_INTERRUPT)) {
702 			F_SET(sp->gp, G_INTERRUPTED);
703 			argp->e_event = E_INTERRUPT;
704 			return (0);
705 		}
706 
707 		/*
708 		 * If an initial part of the characters mapped, they are not
709 		 * further remapped -- return the first one.  Push the rest
710 		 * of the characters, or all of the characters if no initial
711 		 * part mapped, back on the queue.
712 		 */
713 		if (init_nomap) {
714 			if (v_event_push(sp, NULL, qp->output + qp->ilen,
715 			    qp->olen - qp->ilen, CH_MAPPED))
716 				return (1);
717 			if (v_event_push(sp, NULL,
718 			    qp->output, qp->ilen, CH_NOMAP | CH_MAPPED))
719 				return (1);
720 			evp = &wp->i_event[wp->i_next];
721 			goto nomap;
722 		}
723 		if (v_event_push(sp, NULL, qp->output, qp->olen, CH_MAPPED))
724 			return (1);
725 		goto newmap;
726 	}
727 
728 	/* Else, push the characters on the queue and return one. */
729 	if (v_event_push(sp, NULL, qp->output, qp->olen, CH_MAPPED | CH_NOMAP))
730 		return (1);
731 
732 	goto nomap;
733 }
734 
735 /*
736  * v_sync --
737  *	Walk the screen lists, sync'ing files to their backup copies.
738  */
739 static void
v_sync(SCR * sp,int flags)740 v_sync(SCR *sp, int flags)
741 {
742 	GS *gp;
743 	WIN *wp;
744 
745 	gp = sp->gp;
746 	TAILQ_FOREACH(wp, &gp->dq, q)
747 		TAILQ_FOREACH(sp, &wp->scrq, q)
748 			rcv_sync(sp, flags);
749 	TAILQ_FOREACH(sp, &gp->hq, q)
750 		rcv_sync(sp, flags);
751 }
752 
753 /*
754  * v_event_err --
755  *	Unexpected event.
756  *
757  * PUBLIC: void v_event_err __P((SCR *, EVENT *));
758  */
759 void
v_event_err(SCR * sp,EVENT * evp)760 v_event_err(SCR *sp, EVENT *evp)
761 {
762 	switch (evp->e_event) {
763 	case E_CHARACTER:
764 		msgq(sp, M_ERR, "276|Unexpected character event");
765 		break;
766 	case E_EOF:
767 		msgq(sp, M_ERR, "277|Unexpected end-of-file event");
768 		break;
769 	case E_INTERRUPT:
770 		msgq(sp, M_ERR, "279|Unexpected interrupt event");
771 		break;
772 	case E_IPCOMMAND:
773 		msgq(sp, M_ERR, "318|Unexpected command or input");
774 		break;
775 	case E_REPAINT:
776 		msgq(sp, M_ERR, "281|Unexpected repaint event");
777 		break;
778 	case E_STRING:
779 		msgq(sp, M_ERR, "285|Unexpected string event");
780 		break;
781 	case E_TIMEOUT:
782 		msgq(sp, M_ERR, "286|Unexpected timeout event");
783 		break;
784 	case E_WRESIZE:
785 		msgq(sp, M_ERR, "316|Unexpected resize event");
786 		break;
787 
788 	/*
789 	 * Theoretically, none of these can occur, as they're handled at the
790 	 * top editor level.
791 	 */
792 	case E_ERR:
793 	case E_SIGHUP:
794 	case E_SIGTERM:
795 	default:
796 		abort();
797 	}
798 }
799 
800 /*
801  * v_event_flush --
802  *	Flush any flagged keys, returning if any keys were flushed.
803  *
804  * PUBLIC: int v_event_flush __P((SCR *, u_int));
805  */
806 int
v_event_flush(SCR * sp,u_int flags)807 v_event_flush(SCR *sp, u_int flags)
808 {
809 	WIN *wp;
810 	int rval;
811 
812 	for (rval = 0, wp = sp->wp; wp->i_cnt != 0 &&
813 	    FL_ISSET(wp->i_event[wp->i_next].e_flags, flags); rval = 1)
814 		QREM(1);
815 	return (rval);
816 }
817 
818 /*
819  * v_event_grow --
820  *	Grow the terminal queue.
821  */
822 static int
v_event_grow(SCR * sp,int add)823 v_event_grow(SCR *sp, int add)
824 {
825 	WIN *wp;
826 	size_t new_nelem, olen;
827 
828 	wp = sp->wp;
829 	new_nelem = wp->i_nelem + add;
830 	olen = wp->i_nelem * sizeof(wp->i_event[0]);
831 	BINC_RET(sp, EVENT, wp->i_event, olen, new_nelem * sizeof(EVENT));
832 	wp->i_nelem = olen / sizeof(wp->i_event[0]);
833 	return (0);
834 }
835 
836 /*
837  * v_key_cmp --
838  *	Compare two keys for sorting.
839  */
840 static int
v_key_cmp(const void * ap,const void * bp)841 v_key_cmp(const void *ap, const void *bp)
842 {
843 	return (((const KEYLIST *)ap)->ch - ((const KEYLIST *)bp)->ch);
844 }
845