1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 1995, by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * wgetch.c
31  *
32  * XCurses Library
33  *
34  * Copyright 1990, 1995 by Mortice Kern Systems Inc.  All rights reserved.
35  *
36  */
37 
38 #ifdef M_RCSID
39 #ifndef lint
40 static char rcsID[] = "$Header: /rd/src/libc/xcurses/rcs/wgetch.c 1.5 1995/06/19 16:12:13 ant Exp $";
41 #endif
42 #endif
43 
44 #include <private.h>
45 
46 /*
47  * Push single-byte character back onto the input queue.
48  *
49  * MKS EXTENSION permits the return value of wgetch(), which
50  * can be a KEY_ value, to be pushed back.
51  */
52 int
ungetch(ch)53 ungetch(ch)
54 int ch;
55 {
56 	int code;
57 
58 #ifdef M_CURSES_TRACE
59 	__m_trace("ungetch(%d)", ch);
60 #endif
61 	code = __xc_ungetc(ch, (WINDOW *) 0) == EOF ? ERR : OK;
62 
63 	return __m_return_code("ungetch", code);
64 }
65 
66 /*
67  * Push a single-byte character or KEY_ value but onto the
68  * input queue.  Ignore the window parameter.
69  */
70 int
__xc_ungetc(int ch,void * w)71 __xc_ungetc(int ch, void *w)
72 {
73 	if (ISFULL())
74 		return EOF;
75 
76 	PUSH(ch);
77 
78 	return 0;
79 }
80 
81 /*
82  * Return true if the SCREEN's stream has an I/O error.
83  * Ignore the window parameter.
84  */
85 int
__xc_ferror(void * w)86 __xc_ferror(void *w)
87 {
88 	return ferror(__m_screen->_if);
89 }
90 
91 /*
92  * Return true if the SCREEN's stream has seen EOF.
93  * Ignore the window parameter.
94  */
95 int
__xc_feof(void * w)96 __xc_feof(void *w)
97 {
98 	return feof(__m_screen->_if);
99 }
100 
101 /*
102  * Clear the error and eof flags of the SCREEN's stream.
103  * Ignore the window parameter.
104  */
105 void
__xc_clearerr(void * w)106 __xc_clearerr(void *w)
107 {
108 	clearerr(__m_screen->_if);
109 }
110 
111 int
wgetch(w)112 wgetch(w)
113 WINDOW *w;
114 {
115 	t_decode *node;
116 	int ch, i, j, timeout;
117 
118 #ifdef M_CURSES_TRACE
119 	__m_trace("wgetch(%p) at (%d, %d).", w, w->_cury, w->_curx);
120 #endif
121 
122 	(void) wrefresh(w);
123 
124 	if (!ISEMPTY())
125 		return __m_return_int("wgetch", POP());
126 
127 	/* Only change the terminal's input method if the window
128 	 * requires different settings from what is currently set.
129 	 * We do this because tcsetattr() on some systems can be
130 	 * _really_ slow to do for each character.
131 	 *
132 	 * NOTE that halfdelay() overrides nodelay() and wtimeout().
133 	 */
134 	if (!(cur_term->_flags & __TERM_HALF_DELAY)
135 	&& (cur_term->_prog.c_cc[VMIN] != w->_vmin
136 	|| cur_term->_prog.c_cc[VTIME] != w->_vtime)) {
137 		cur_term->_prog.c_cc[VMIN] = w->_vmin;
138 		cur_term->_prog.c_cc[VTIME] = w->_vtime;
139 
140 		if (__m_tty_set(&cur_term->_prog) == ERR)
141 			return __m_return_int("wgetch", EOF);
142 	}
143 
144 	if (req_for_input != (char *) 0)
145 		(void) tputs(req_for_input, 1, __m_outc);
146 
147 	clearerr(__m_screen->_if);
148 	ch = fgetc(__m_screen->_if);
149 
150 	/* Only check for function keys if keypad is true and we
151 	 * did not read a KEY_ value (which are < 0), nor EOF.
152 	 * It is conceivable that a KEY_ was pushed back with
153 	 * ungetch().
154 	 */
155 	if ((w->_flags & W_USE_KEYPAD) && 0 <= ch && ch != EOF) {
156 		/* Treat the termios ERASE key the same as key_backspace.
157 		 *
158 		 * We used to change the key_backspace entry to be a string
159 		 * containing the ERASE key in setupterm(), but this would
160 		 * then disable the real terminfo entry for the backspace key.
161 		 * Apparently VT300 terminals change the key code/sequence
162 		 * of the backspace key in application keypad mode.
163 		 * See SR 6014.
164 		 *
165 		 * Refer to _shell instead of _prog, since _shell will
166 		 * correctly reflect the user's prefered settings, whereas
167 		 * _prog may not have been initialised if both input and
168 		 * output have been redirected.
169 		 */
170 #ifdef _POSIX_VDISABLE
171 		if (cur_term->_shell.c_cc[VERASE] != _POSIX_VDISABLE)
172 #endif
173 			if (ch == cur_term->_shell.c_cc[VERASE])
174 				return __m_return_int("wgetch", KEY_BACKSPACE);
175 
176 		/* Begin check for function key. */
177 		node = (t_decode *) __m_screen->_decode;
178 
179 		/* Use input stack as a queue. */
180 		timeout = w->_flags & W_USE_TIMEOUT;
181 		for (RESET(); !ISFULL(); ) {
182 			PUSH(ch);
183 
184 			while (node->ch != ch) {
185 				node = node->sibling;
186 				if (node == (t_decode *) 0)
187 					goto invalid;
188 			}
189 
190 			/* Found funuction key? */
191 			if (node->key != 0) {
192 				RESET();
193 				return __m_return_int("wgetch", node->key);
194 			}
195 
196 			/* Setup interbyte timer (once only).  fgetc() will
197 			 * return EOF if no input received, which may not be
198 			 * a true EOF.
199 			 */
200 			if (timeout) {
201 				cur_term->_prog.c_cc[VMIN] = 0;
202 				cur_term->_prog.c_cc[VTIME] =
203 					M_CURSES_INTERBYTE_TIME;
204 				(void) __m_tty_set(&cur_term->_prog);
205 			}
206 			timeout = 0;
207 
208 			if ((ch = fgetc(__m_screen->_if)) == EOF)
209 				/* Timeout or real eof. */
210 				break;
211 
212 			/* Incomplete sequence, continue. */
213 			node = node->child;
214 		}
215 invalid:
216 		/* Reverse contents of the input queue to form a stack. */
217 		for (i = 0, j = __m_screen->_unget._count; i < --j; ++i) {
218 			ch = __m_screen->_unget._stack[i];
219 			__m_screen->_unget._stack[i] =
220 				__m_screen->_unget._stack[j];
221 			__m_screen->_unget._stack[j] = ch;
222 		}
223 
224 		/* Return first byte received or EOF. */
225 		ch = POP();
226 	}
227 
228 	if ((__m_screen->_flags & S_ECHO) && 0 <= ch && ch != EOF)  {
229 		(void) waddch(w, ch);
230 		(void) wrefresh(w);
231 	}
232 
233 	return __m_return_int("wgetch", ch);
234 }
235 
236