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getch.c revision 1.30
      1 /*	$NetBSD: getch.c,v 1.30 2000/07/31 16:22:46 itojun Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1981, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include <sys/cdefs.h>
     37 #ifndef lint
     38 #if 0
     39 static char sccsid[] = "@(#)getch.c	8.2 (Berkeley) 5/4/94";
     40 #else
     41 __RCSID("$NetBSD: getch.c,v 1.30 2000/07/31 16:22:46 itojun Exp $");
     42 #endif
     43 #endif					/* not lint */
     44 
     45 #include <string.h>
     46 #include <stdlib.h>
     47 #include <unistd.h>
     48 #include <stdio.h>
     49 #include "curses.h"
     50 #include "curses_private.h"
     51 
     52 /* defined in setterm.c */
     53 extern struct tinfo *_cursesi_genbuf;
     54 
     55 #define DEFAULT_DELAY 2			/* default delay for timeout() */
     56 
     57 /*
     58  * Keyboard input handler.  Do this by snarfing
     59  * all the info we can out of the termcap entry for TERM and putting it
     60  * into a set of keymaps.  A keymap is an array the size of all the possible
     61  * single characters we can get, the contents of the array is a structure
     62  * that contains the type of entry this character is (i.e. part/end of a
     63  * multi-char sequence or a plain char) and either a pointer which will point
     64  * to another keymap (in the case of a multi-char sequence) OR the data value
     65  * that this key should return.
     66  *
     67  */
     68 
     69 /* private data structures for holding the key definitions */
     70 typedef struct keymap keymap_t;
     71 typedef struct key_entry key_entry_t;
     72 
     73 struct key_entry {
     74 	short   type;		/* type of key this is */
     75 	union {
     76 		keymap_t *next;	/* next keymap is key is multi-key sequence */
     77 		wchar_t   symbol;	/* key symbol if key is a leaf entry */
     78 	} value;
     79 };
     80 /* Types of key structures we can have */
     81 #define KEYMAP_MULTI  1		/* part of a multi char sequence */
     82 #define KEYMAP_LEAF   2		/* key has a symbol associated with it, either
     83 				 * it is the end of a multi-char sequence or a
     84 				 * single char key that generates a symbol */
     85 
     86 /* allocate this many key_entry structs at once to speed start up must
     87  * be a power of 2.
     88  */
     89 #define KEYMAP_ALLOC_CHUNK 4
     90 
     91 /* The max number of different chars we can receive */
     92 #define MAX_CHAR 256
     93 
     94 struct keymap {
     95 	int	count;		/* count of number of key structs allocated */
     96 	short	mapping[MAX_CHAR]; /* mapping of key to allocated structs */
     97 	key_entry_t **key;	/* dynamic array of keys */
     98 };
     99 
    100 
    101 /* Key buffer */
    102 #define INBUF_SZ 16		/* size of key buffer - must be larger than
    103 				 * longest multi-key sequence */
    104 static wchar_t  inbuf[INBUF_SZ];
    105 static int     start, end, working; /* pointers for manipulating inbuf data */
    106 
    107 #define INC_POINTER(ptr)  do {	\
    108 	(ptr)++;		\
    109 	ptr %= INBUF_SZ;	\
    110 } while(/*CONSTCOND*/0)
    111 
    112 static short	state;		/* state of the inkey function */
    113 
    114 #define INKEY_NORM	 0	/* no key backlog to process */
    115 #define INKEY_ASSEMBLING 1	/* assembling a multi-key sequence */
    116 #define INKEY_BACKOUT	 2	/* recovering from an unrecognised key */
    117 #define INKEY_TIMEOUT	 3	/* multi-key sequence timeout */
    118 
    119 /* The termcap data we are interested in and the symbols they map to */
    120 struct tcdata {
    121 	const char	*name;	/* name of termcap entry */
    122 	wchar_t	symbol;		/* the symbol associated with it */
    123 };
    124 
    125 static const struct tcdata tc[] = {
    126 	{"!1", KEY_SSAVE},
    127 	{"!2", KEY_SSUSPEND},
    128 	{"!3", KEY_SUNDO},
    129 	{"#1", KEY_SHELP},
    130 	{"#2", KEY_SHOME},
    131 	{"#3", KEY_SIC},
    132 	{"#4", KEY_SLEFT},
    133 	{"%0", KEY_REDO},
    134 	{"%1", KEY_HELP},
    135 	{"%2", KEY_MARK},
    136 	{"%3", KEY_MESSAGE},
    137 	{"%4", KEY_MOVE},
    138 	{"%5", KEY_NEXT},
    139 	{"%6", KEY_OPEN},
    140 	{"%7", KEY_OPTIONS},
    141 	{"%8", KEY_PREVIOUS},
    142 	{"%9", KEY_PRINT},
    143 	{"%a", KEY_SMESSAGE},
    144 	{"%b", KEY_SMOVE},
    145 	{"%c", KEY_SNEXT},
    146 	{"%d", KEY_SOPTIONS},
    147 	{"%e", KEY_SPREVIOUS},
    148 	{"%f", KEY_SPRINT},
    149 	{"%g", KEY_SREDO},
    150 	{"%h", KEY_SREPLACE},
    151 	{"%i", KEY_SRIGHT},
    152 	{"%j", KEY_SRSUME},
    153 	{"&0", KEY_SCANCEL},
    154 	{"&1", KEY_REFERENCE},
    155 	{"&2", KEY_REFRESH},
    156 	{"&3", KEY_REPLACE},
    157 	{"&4", KEY_RESTART},
    158 	{"&5", KEY_RESUME},
    159 	{"&6", KEY_SAVE},
    160 	{"&7", KEY_SUSPEND},
    161 	{"&8", KEY_UNDO},
    162 	{"&9", KEY_SBEG},
    163 	{"*0", KEY_SFIND},
    164 	{"*1", KEY_SCOMMAND},
    165 	{"*2", KEY_SCOPY},
    166 	{"*3", KEY_SCREATE},
    167 	{"*4", KEY_SDC},
    168 	{"*5", KEY_SDL},
    169 	{"*6", KEY_SELECT},
    170 	{"*7", KEY_SEND},
    171 	{"*8", KEY_SEOL},
    172 	{"*9", KEY_SEXIT},
    173 	{"@0", KEY_FIND},
    174 	{"@1", KEY_BEG},
    175 	{"@2", KEY_CANCEL},
    176 	{"@3", KEY_CLOSE},
    177 	{"@4", KEY_COMMAND},
    178 	{"@5", KEY_COPY},
    179 	{"@6", KEY_CREATE},
    180 	{"@7", KEY_END},
    181 	{"@8", KEY_ENTER},
    182 	{"@9", KEY_EXIT},
    183 	{"F1", KEY_F(11)},
    184 	{"F2", KEY_F(12)},
    185 	{"F3", KEY_F(13)},
    186 	{"F4", KEY_F(14)},
    187 	{"F5", KEY_F(15)},
    188 	{"F6", KEY_F(16)},
    189 	{"F7", KEY_F(17)},
    190 	{"F8", KEY_F(18)},
    191 	{"F9", KEY_F(19)},
    192 	{"FA", KEY_F(20)},
    193 	{"FB", KEY_F(21)},
    194 	{"FC", KEY_F(22)},
    195 	{"FD", KEY_F(23)},
    196 	{"FE", KEY_F(24)},
    197 	{"FF", KEY_F(25)},
    198 	{"FG", KEY_F(26)},
    199 	{"FH", KEY_F(27)},
    200 	{"FI", KEY_F(28)},
    201 	{"FJ", KEY_F(29)},
    202 	{"FK", KEY_F(30)},
    203 	{"FL", KEY_F(31)},
    204 	{"FM", KEY_F(32)},
    205 	{"FN", KEY_F(33)},
    206 	{"FO", KEY_F(34)},
    207 	{"FP", KEY_F(35)},
    208 	{"FQ", KEY_F(36)},
    209 	{"FR", KEY_F(37)},
    210 	{"FS", KEY_F(38)},
    211 	{"FT", KEY_F(39)},
    212 	{"FU", KEY_F(40)},
    213 	{"FV", KEY_F(41)},
    214 	{"FW", KEY_F(42)},
    215 	{"FX", KEY_F(43)},
    216 	{"FY", KEY_F(44)},
    217 	{"FZ", KEY_F(45)},
    218 	{"Fa", KEY_F(46)},
    219 	{"Fb", KEY_F(47)},
    220 	{"Fc", KEY_F(48)},
    221 	{"Fd", KEY_F(49)},
    222 	{"Fe", KEY_F(50)},
    223 	{"Ff", KEY_F(51)},
    224 	{"Fg", KEY_F(52)},
    225 	{"Fh", KEY_F(53)},
    226 	{"Fi", KEY_F(54)},
    227 	{"Fj", KEY_F(55)},
    228 	{"Fk", KEY_F(56)},
    229 	{"Fl", KEY_F(57)},
    230 	{"Fm", KEY_F(58)},
    231 	{"Fn", KEY_F(59)},
    232 	{"Fo", KEY_F(60)},
    233 	{"Fp", KEY_F(61)},
    234 	{"Fq", KEY_F(62)},
    235 	{"Fr", KEY_F(63)},
    236 	{"K1", KEY_A1},
    237 	{"K2", KEY_B2},
    238 	{"K3", KEY_A3},
    239 	{"K4", KEY_C1},
    240 	{"K5", KEY_C3},
    241 	{"Km", KEY_MOUSE},
    242 	{"k0", KEY_F0},
    243 	{"k1", KEY_F(1)},
    244 	{"k2", KEY_F(2)},
    245 	{"k3", KEY_F(3)},
    246 	{"k4", KEY_F(4)},
    247 	{"k5", KEY_F(5)},
    248 	{"k6", KEY_F(6)},
    249 	{"k7", KEY_F(7)},
    250 	{"k8", KEY_F(8)},
    251 	{"k9", KEY_F(9)},
    252 	{"k;", KEY_F(10)},
    253 	{"kA", KEY_IL},
    254 	{"ka", KEY_CATAB},
    255 	{"kB", KEY_BTAB},
    256 	{"kb", KEY_BACKSPACE},
    257 	{"kC", KEY_CLEAR},
    258 	{"kD", KEY_DC},
    259 	{"kd", KEY_DOWN},
    260 	{"kE", KEY_EOL},
    261 	{"kF", KEY_SF},
    262 	{"kH", KEY_LL},
    263 	{"kh", KEY_HOME},
    264 	{"kI", KEY_IC},
    265 	{"kL", KEY_DL},
    266 	{"kl", KEY_LEFT},
    267 	{"kM", KEY_EIC},
    268 	{"kN", KEY_NPAGE},
    269 	{"kP", KEY_PPAGE},
    270 	{"kR", KEY_SR},
    271 	{"kr", KEY_RIGHT},
    272 	{"kS", KEY_EOS},
    273 	{"kT", KEY_STAB},
    274 	{"kt", KEY_CTAB},
    275 	{"ku", KEY_UP}
    276 };
    277 /* Number of TC entries .... */
    278 static const int num_tcs = (sizeof(tc) / sizeof(struct tcdata));
    279 
    280 /* The root keymap */
    281 
    282 static keymap_t *base_keymap;
    283 
    284 /* prototypes for private functions */
    285 static key_entry_t *add_new_key(keymap_t *current, char chr, int key_type,
    286 				int symbol);
    287 static keymap_t		*new_keymap(void);	/* create a new keymap */
    288 static key_entry_t	*new_key(void);		/* create a new key entry */
    289 static wchar_t		inkey(int to, int delay);
    290 
    291 /*
    292  * Add a new key entry to the keymap pointed to by current.  Entry
    293  * contains the character to add to the keymap, type is the type of
    294  * entry to add (either multikey or leaf) and symbol is the symbolic
    295  * value for a leaf type entry.  The function returns a pointer to the
    296  * new keymap entry.
    297  */
    298 static key_entry_t *
    299 add_new_key(keymap_t *current, char chr, int key_type, int symbol)
    300 {
    301 	key_entry_t *the_key;
    302         int i;
    303 
    304 #ifdef DEBUG
    305 	__CTRACE("Adding character %s of type %d, symbol 0x%x\n", unctrl(chr),
    306 		 key_type, symbol);
    307 #endif
    308 	if (current->mapping[(unsigned) chr] < 0) {
    309 		  /* first time for this char */
    310 		current->mapping[(unsigned) chr] = current->count;	/* map new entry */
    311 		  /* make sure we have room in the key array first */
    312 		if ((current->count & (KEYMAP_ALLOC_CHUNK - 1)) == 0)
    313 		{
    314 			if ((current->key =
    315 			     realloc(current->key,
    316 				     (current->count) * sizeof(key_entry_t *)
    317 				     + KEYMAP_ALLOC_CHUNK * sizeof(key_entry_t *))) == NULL) {
    318 				fprintf(stderr,
    319 					"Could not malloc for key entry\n");
    320 				exit(1);
    321 			}
    322 
    323 			the_key = new_key();
    324                         for (i = 0; i < KEYMAP_ALLOC_CHUNK; i++) {
    325                                 current->key[current->count + i]
    326 					= &the_key[i];
    327                         }
    328                 }
    329 
    330                   /* point at the current key array element to use */
    331                 the_key = current->key[current->count];
    332 
    333 		the_key->type = key_type;
    334 
    335 		switch (key_type) {
    336 		  case KEYMAP_MULTI:
    337 			    /* need for next key */
    338 #ifdef DEBUG
    339 			  __CTRACE("Creating new keymap\n");
    340 #endif
    341 			  the_key->value.next = new_keymap();
    342 			  break;
    343 
    344 		  case KEYMAP_LEAF:
    345 				/* the associated symbol for the key */
    346 #ifdef DEBUG
    347 			  __CTRACE("Adding leaf key\n");
    348 #endif
    349 			  the_key->value.symbol = symbol;
    350 			  break;
    351 
    352 		  default:
    353 			  fprintf(stderr, "add_new_key: bad type passed\n");
    354 			  exit(1);
    355 		}
    356 
    357 		current->count++;
    358 	} else {
    359 		  /* the key is already known - just return the address. */
    360 #ifdef DEBUG
    361 		__CTRACE("Keymap already known\n");
    362 #endif
    363 		the_key = current->key[current->mapping[(unsigned) chr]];
    364 	}
    365 
    366         return the_key;
    367 }
    368 
    369 /*
    370  * Init_getch - initialise all the pointers & structures needed to make
    371  * getch work in keypad mode.
    372  *
    373  */
    374 void
    375 __init_getch(void)
    376 {
    377 	char entry[1024], *p;
    378 	int     i, j, length, key_ent;
    379 	size_t limit;
    380 	key_entry_t *tmp_key;
    381 	keymap_t *current;
    382 #ifdef DEBUG
    383 	int k;
    384 #endif
    385 
    386 	/* init the inkey state variable */
    387 	state = INKEY_NORM;
    388 
    389 	/* init the base keymap */
    390 	base_keymap = new_keymap();
    391 
    392 	/* key input buffer pointers */
    393 	start = end = working = 0;
    394 
    395 	/* now do the termcap snarfing ... */
    396 	for (i = 0; i < num_tcs; i++) {
    397 		p = entry;
    398 		limit = 1023;
    399 		if (t_getstr(_cursesi_genbuf, tc[i].name, &p, &limit) != NULL) {
    400 			current = base_keymap;	/* always start with
    401 						 * base keymap. */
    402 			length = (int) strlen(entry);
    403 #ifdef DEBUG
    404 			__CTRACE("Processing termcap entry %s, sequence ",
    405 				 tc[i].name);
    406 			for (k = 0; k <= length -1; k++)
    407 				__CTRACE("%s", unctrl(entry[k]));
    408 			__CTRACE("\n");
    409 #endif
    410 			for (j = 0; j < length - 1; j++) {
    411 				  /* add the entry to the struct */
    412 				tmp_key = add_new_key(current,
    413 						      entry[j],
    414 						      KEYMAP_MULTI, 0);
    415 
    416 				  /* index into the key array - it's
    417 				     clearer if we stash this */
    418 				key_ent = current->mapping[
    419 					(unsigned) entry[j]];
    420 
    421 				current->key[key_ent] = tmp_key;
    422 
    423 				  /* next key uses this map... */
    424 				current = current->key[key_ent]->value.next;
    425 			}
    426 
    427 				/* this is the last key in the sequence (it
    428 				 * may have been the only one but that does
    429 				 * not matter) this means it is a leaf key and
    430 				 * should have a symbol associated with it.
    431 				 */
    432 			tmp_key = add_new_key(current,
    433 					      entry[length - 1],
    434 					      KEYMAP_LEAF,
    435 					      tc[i].symbol);
    436 			current->key[
    437 				current->mapping[(int)entry[length - 1]]] =
    438 			tmp_key;
    439 		}
    440 	}
    441 }
    442 
    443 
    444 /*
    445  * new_keymap - allocates & initialises a new keymap structure.  This
    446  * function returns a pointer to the new keymap.
    447  *
    448  */
    449 static keymap_t *
    450 new_keymap(void)
    451 {
    452 	int     i;
    453 	keymap_t *new_map;
    454 
    455 	if ((new_map = malloc(sizeof(keymap_t))) == NULL) {
    456 		perror("Inkey: Cannot allocate new keymap");
    457 		exit(2);
    458 	}
    459 
    460 	/* Initialise the new map */
    461 	new_map->count = 0;
    462 	for (i = 0; i < MAX_CHAR; i++) {
    463 		new_map->mapping[i] = -1;	/* no mapping for char */
    464 	}
    465 
    466 	/* key array will be allocated when first key is added */
    467 	new_map->key = NULL;
    468 
    469 	return new_map;
    470 }
    471 
    472 /*
    473  * new_key - allocates & initialises a new key entry.  This function returns
    474  * a pointer to the newly allocated key entry.
    475  *
    476  */
    477 static key_entry_t *
    478 new_key(void)
    479 {
    480 	key_entry_t *new_one;
    481 	int i;
    482 
    483 	if ((new_one = malloc(KEYMAP_ALLOC_CHUNK * sizeof(key_entry_t)))
    484 	    == NULL) {
    485 		perror("inkey: Cannot allocate new key entry chunk");
    486 		exit(2);
    487 	}
    488 
    489 	for (i = 0; i < KEYMAP_ALLOC_CHUNK; i++) {
    490 		new_one[i].type = 0;
    491 		new_one[i].value.next = NULL;
    492 	}
    493 
    494 	return new_one;
    495 }
    496 
    497 /*
    498  * inkey - do the work to process keyboard input, check for multi-key
    499  * sequences and return the appropriate symbol if we get a match.
    500  *
    501  */
    502 
    503 wchar_t
    504 inkey(int to, int delay)
    505 {
    506 	wchar_t		 k;
    507 	int              c;
    508 	keymap_t	*current = base_keymap;
    509 
    510 	k = 0;		/* XXX gcc -Wuninitialized */
    511 
    512 	for (;;) {		/* loop until we get a complete key sequence */
    513 reread:
    514 		if (state == INKEY_NORM) {
    515 			if (delay && __timeout(delay) == ERR)
    516 				return ERR;
    517 			if ((c = getchar()) == EOF) {
    518 				clearerr(stdin);
    519 				return ERR;
    520 			}
    521 
    522 			if (delay && (__notimeout() == ERR))
    523 				return ERR;
    524 
    525 			k = (wchar_t) c;
    526 #ifdef DEBUG
    527 			__CTRACE("inkey (state normal) got '%s'\n", unctrl(k));
    528 #endif
    529 
    530 			working = start;
    531 			inbuf[working] = k;
    532 			INC_POINTER(working);
    533 			end = working;
    534 			state = INKEY_ASSEMBLING;	/* go to the assembling
    535 							 * state now */
    536 		} else if (state == INKEY_BACKOUT) {
    537 			k = inbuf[working];
    538 			INC_POINTER(working);
    539 			if (working == end) {	/* see if we have run
    540 						 * out of keys in the
    541 						 * backlog */
    542 
    543 				/* if we have then switch to
    544 				   assembling */
    545 				state = INKEY_ASSEMBLING;
    546 			}
    547 		} else if (state == INKEY_ASSEMBLING) {
    548 			/* assembling a key sequence */
    549 			if (delay) {
    550 				if (__timeout(to ? DEFAULT_DELAY : delay) == ERR)
    551 						return ERR;
    552 			} else {
    553 				if (to && (__timeout(DEFAULT_DELAY) == ERR))
    554 					return ERR;
    555 			}
    556 
    557 			c = getchar();
    558 			if (ferror(stdin)) {
    559 				clearerr(stdin);
    560 				return ERR;
    561 			}
    562 
    563 			if ((to || delay) && (__notimeout() == ERR))
    564 					return ERR;
    565 
    566 			k = (wchar_t) c;
    567 #ifdef DEBUG
    568 			__CTRACE("inkey (state assembling) got '%s'\n", unctrl(k));
    569 #endif
    570 			if (feof(stdin)) {	/* inter-char timeout,
    571 						 * start backing out */
    572 				clearerr(stdin);
    573 				if (start == end)
    574 					/* no chars in the buffer, restart */
    575 					goto reread;
    576 
    577 				k = inbuf[start];
    578 				state = INKEY_TIMEOUT;
    579 			} else {
    580 				inbuf[working] = k;
    581 				INC_POINTER(working);
    582 				end = working;
    583 			}
    584 		} else {
    585 			fprintf(stderr, "Inkey state screwed - exiting!!!");
    586 			exit(2);
    587 		}
    588 
    589 		/* Check key has no special meaning and we have not timed out */
    590 		if ((state == INKEY_TIMEOUT) || (current->mapping[k] < 0)) {
    591 			/* return the first key we know about */
    592 			k = inbuf[start];
    593 
    594 			INC_POINTER(start);
    595 			working = start;
    596 
    597 			if (start == end) {	/* only one char processed */
    598 				state = INKEY_NORM;
    599 			} else {/* otherwise we must have more than one char
    600 				 * to backout */
    601 				state = INKEY_BACKOUT;
    602 			}
    603 			return k;
    604 		} else {	/* must be part of a multikey sequence */
    605 			/* check for completed key sequence */
    606 			if (current->key[current->mapping[k]]->type == KEYMAP_LEAF) {
    607 				start = working;	/* eat the key sequence
    608 							 * in inbuf */
    609 
    610 				/* check if inbuf empty now */
    611 				if (start == end) {
    612 					/* if it is go back to normal */
    613 					state = INKEY_NORM;
    614 				} else {
    615 					/* otherwise go to backout state */
    616 					state = INKEY_BACKOUT;
    617 				}
    618 
    619 				/* return the symbol */
    620 				return current->key[current->mapping[k]]->value.symbol;
    621 
    622 			} else {
    623 				/*
    624 				 * Step on to next part of the multi-key
    625 				 * sequence.
    626 				 */
    627 				current = current->key[current->mapping[k]]->value.next;
    628 			}
    629 		}
    630 	}
    631 }
    632 
    633 #ifndef _CURSES_USE_MACROS
    634 /*
    635  * getch --
    636  *	Read in a character from stdscr.
    637  */
    638 int
    639 getch(void)
    640 {
    641 	return wgetch(stdscr);
    642 }
    643 
    644 /*
    645  * mvgetch --
    646  *      Read in a character from stdscr at the given location.
    647  */
    648 int
    649 mvgetch(int y, int x)
    650 {
    651 	return mvwgetch(stdscr, y, x);
    652 }
    653 
    654 /*
    655  * mvwgetch --
    656  *      Read in a character from stdscr at the given location in the
    657  *      given window.
    658  */
    659 int
    660 mvwgetch(WINDOW *win, int y, int x)
    661 {
    662 	if (wmove(win, y, x) == ERR)
    663 		return ERR;
    664 
    665 	return wgetch(win);
    666 }
    667 
    668 #endif
    669 
    670 /*
    671  * wgetch --
    672  *	Read in a character from the window.
    673  */
    674 int
    675 wgetch(WINDOW *win)
    676 {
    677 	int inp, weset;
    678 	int c;
    679 
    680 	if (!(win->flags & __SCROLLOK) && (win->flags & __FULLWIN)
    681 	    && win->curx == win->maxx - 1 && win->cury == win->maxy - 1
    682 	    && __echoit)
    683 		return (ERR);
    684 
    685 	wrefresh(win);
    686 #ifdef DEBUG
    687 	__CTRACE("wgetch: __echoit = %d, __rawmode = %d, flags = %0.2o\n",
    688 	    __echoit, __rawmode, win->flags);
    689 #endif
    690 	if (__echoit && !__rawmode) {
    691 		cbreak();
    692 		weset = 1;
    693 	} else
    694 		weset = 0;
    695 
    696 	__save_termios();
    697 
    698 	if (win->flags & __KEYPAD) {
    699 		switch (win->delay)
    700 		{
    701 		case -1:
    702 			inp = inkey (win->flags & __NOTIMEOUT ? 0 : 1, 0);
    703 			break;
    704 		case 0:
    705 			if (__nodelay() == ERR) {
    706 				__restore_termios();
    707 				return ERR;
    708 			}
    709 			inp = inkey(0, 0);
    710 			break;
    711 		default:
    712 			inp = inkey(win->flags & __NOTIMEOUT ? 0 : 1, win->delay);
    713 			break;
    714 		}
    715 	} else {
    716 		switch (win->delay)
    717 		{
    718 		case -1:
    719 			break;
    720 		case 0:
    721 			if (__nodelay() == ERR) {
    722 				__restore_termios();
    723 				return ERR;
    724 			}
    725 			break;
    726 		default:
    727 			if (__timeout(win->delay) == ERR) {
    728 				__restore_termios();
    729 				return ERR;
    730 			}
    731 			break;
    732 		}
    733 
    734 		c = getchar();
    735 		if (feof(stdin)) {
    736 			clearerr(stdin);
    737 			__restore_termios();
    738 			return ERR;	/* we have timed out */
    739 		}
    740 
    741 		if (ferror(stdin)) {
    742 			clearerr(stdin);
    743 			inp = ERR;
    744 		} else {
    745 			inp = c;
    746 		}
    747 	}
    748 #ifdef DEBUG
    749 	if (inp > 255)
    750 		  /* we have a key symbol - treat it differently */
    751 		  /* XXXX perhaps __unctrl should be expanded to include
    752 		   * XXXX the keysyms in the table....
    753 		   */
    754 		__CTRACE("wgetch assembled keysym 0x%x\n", inp);
    755 	else
    756 		__CTRACE("wgetch got '%s'\n", unctrl(inp));
    757 #endif
    758 	if (win->delay > -1) {
    759 		if (__delay() == ERR) {
    760 			__restore_termios();
    761 			return ERR;
    762 		}
    763 	}
    764 
    765 	__restore_termios();
    766 
    767 	if (__echoit)
    768 		waddch(win, (chtype) inp);
    769 
    770 	if (weset)
    771 		nocbreak();
    772 
    773 	return ((inp < 0) || (inp == ERR) ? ERR : inp);
    774 }
    775 
    776 /*
    777  * ungetch --
    778  *     Put the character back into the input queue.
    779  */
    780 int
    781 ungetch(int c)
    782 {
    783 	return ((ungetc(c, stdin) == EOF) ? ERR : OK);
    784 }
    785