1/* $OpenBSD: lib_kernel.c,v 1.4 2023/10/17 09:52:09 nicm Exp $ */
2
3/****************************************************************************
4 * Copyright 2020-2022,2023 Thomas E. Dickey                                *
5 * Copyright 1998-2009,2010 Free Software Foundation, Inc.                  *
6 *                                                                          *
7 * Permission is hereby granted, free of charge, to any person obtaining a  *
8 * copy of this software and associated documentation files (the            *
9 * "Software"), to deal in the Software without restriction, including      *
10 * without limitation the rights to use, copy, modify, merge, publish,      *
11 * distribute, distribute with modifications, sublicense, and/or sell       *
12 * copies of the Software, and to permit persons to whom the Software is    *
13 * furnished to do so, subject to the following conditions:                 *
14 *                                                                          *
15 * The above copyright notice and this permission notice shall be included  *
16 * in all copies or substantial portions of the Software.                   *
17 *                                                                          *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
21 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
24 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
25 *                                                                          *
26 * Except as contained in this notice, the name(s) of the above copyright   *
27 * holders shall not be used in advertising or otherwise to promote the     *
28 * sale, use or other dealings in this Software without prior written       *
29 * authorization.                                                           *
30 ****************************************************************************/
31
32/****************************************************************************
33 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
34 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
35 *     and: Thomas E. Dickey                        2002                    *
36 *     and: Juergen Pfeifer                         2009                    *
37 ****************************************************************************/
38
39/*
40 *	lib_kernel.c
41 *
42 *	Misc. low-level routines:
43 *		erasechar()
44 *		killchar()
45 *		flushinp()
46 *
47 * The baudrate() and delay_output() functions could logically live here,
48 * but are in other modules to reduce the static-link size of programs
49 * that use only these facilities.
50 */
51
52#include <curses.priv.h>
53
54MODULE_ID("$Id: lib_kernel.c,v 1.4 2023/10/17 09:52:09 nicm Exp $")
55
56#ifdef TERMIOS
57static int
58_nc_vdisable(void)
59{
60    int value = -1;
61#if defined(_POSIX_VDISABLE) && HAVE_UNISTD_H
62    value = _POSIX_VDISABLE;
63#endif
64#if defined(_PC_VDISABLE) && HAVE_FPATHCONF
65    if (value == -1) {
66	value = (int) fpathconf(0, _PC_VDISABLE);
67	if (value == -1) {
68	    value = 0377;
69	}
70    }
71#elif defined(VDISABLE)
72    if (value == -1)
73	value = VDISABLE;
74#endif
75    return value;
76}
77#endif /* TERMIOS */
78
79/*
80 *	erasechar()
81 *
82 *	Return erase character as given in cur_term->Ottyb.
83 *
84 */
85
86NCURSES_EXPORT(char)
87NCURSES_SP_NAME(erasechar) (NCURSES_SP_DCL0)
88{
89    int result = ERR;
90    TERMINAL *termp = TerminalOf(SP_PARM);
91
92    T((T_CALLED("erasechar(%p)"), (void *) SP_PARM));
93
94    if (termp != 0) {
95#ifdef TERMIOS
96	result = termp->Ottyb.c_cc[VERASE];
97	if (result == _nc_vdisable())
98	    result = ERR;
99#elif defined(EXP_WIN32_DRIVER)
100	result = ERR;
101#else
102	result = termp->Ottyb.sg_erase;
103#endif
104    }
105    returnChar((char) result);
106}
107
108#if NCURSES_SP_FUNCS
109NCURSES_EXPORT(char)
110erasechar(void)
111{
112    return NCURSES_SP_NAME(erasechar) (CURRENT_SCREEN);
113}
114#endif
115
116/*
117 *	killchar()
118 *
119 *	Return kill character as given in cur_term->Ottyb.
120 *
121 */
122
123NCURSES_EXPORT(char)
124NCURSES_SP_NAME(killchar) (NCURSES_SP_DCL0)
125{
126    int result = ERR;
127    TERMINAL *termp = TerminalOf(SP_PARM);
128
129    T((T_CALLED("killchar(%p)"), (void *) SP_PARM));
130
131    if (termp != 0) {
132#ifdef TERMIOS
133	result = termp->Ottyb.c_cc[VKILL];
134	if (result == _nc_vdisable())
135	    result = ERR;
136#elif defined(EXP_WIN32_DRIVER)
137	result = ERR;
138#else
139	result = termp->Ottyb.sg_kill;
140#endif
141    }
142    returnChar((char) result);
143}
144
145#if NCURSES_SP_FUNCS
146NCURSES_EXPORT(char)
147killchar(void)
148{
149    return NCURSES_SP_NAME(killchar) (CURRENT_SCREEN);
150}
151#endif
152
153static void
154flush_input(int fd)
155{
156#ifdef TERMIOS
157    tcflush(fd, TCIFLUSH);
158#else /* !TERMIOS */
159    errno = 0;
160    do {
161#if defined(EXP_WIN32_DRIVER)
162	_nc_console_flush(_nc_console_fd2handle(fd));
163#else
164	ioctl(fd, TIOCFLUSH, 0);
165#endif
166    } while
167	(errno == EINTR);
168#endif
169}
170
171/*
172 *	flushinp()
173 *
174 *	Flush any input on tty
175 */
176
177NCURSES_EXPORT(int)
178NCURSES_SP_NAME(flushinp) (NCURSES_SP_DCL0)
179{
180    T((T_CALLED("flushinp(%p)"), (void *) SP_PARM));
181
182    if (SP_PARM != 0) {
183	if (NC_ISATTY(SP_PARM->_ifd))
184	    flush_input(SP_PARM->_ifd);
185	else if (NC_ISATTY(SP_PARM->_ofd))
186	    flush_input(SP_PARM->_ofd);
187	if (SP_PARM) {
188	    SP_PARM->_fifohead = -1;
189	    SP_PARM->_fifotail = 0;
190	    SP_PARM->_fifopeek = 0;
191	}
192	returnCode(OK);
193    }
194    returnCode(ERR);
195}
196
197#if NCURSES_SP_FUNCS
198NCURSES_EXPORT(int)
199flushinp(void)
200{
201    return NCURSES_SP_NAME(flushinp) (CURRENT_SCREEN);
202}
203#endif
204