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