1 /* $OpenBSD: lib_unget_wch.c,v 1.1 2010/09/06 17:26:17 nicm Exp $ */
2 
3 /****************************************************************************
4  * Copyright (c) 2002-2007,2008 Free Software Foundation, Inc.              *
5  *                                                                          *
6  * Permission is hereby granted, free of charge, to any person obtaining a  *
7  * copy of this software and associated documentation files (the            *
8  * "Software"), to deal in the Software without restriction, including      *
9  * without limitation the rights to use, copy, modify, merge, publish,      *
10  * distribute, distribute with modifications, sublicense, and/or sell       *
11  * copies of the Software, and to permit persons to whom the Software is    *
12  * furnished to do so, subject to the following conditions:                 *
13  *                                                                          *
14  * The above copyright notice and this permission notice shall be included  *
15  * in all copies or substantial portions of the Software.                   *
16  *                                                                          *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
20  * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
23  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
24  *                                                                          *
25  * Except as contained in this notice, the name(s) of the above copyright   *
26  * holders shall not be used in advertising or otherwise to promote the     *
27  * sale, use or other dealings in this Software without prior written       *
28  * authorization.                                                           *
29  ****************************************************************************/
30 
31 /****************************************************************************
32  *  Author: Thomas E. Dickey 2002                                           *
33  ****************************************************************************/
34 
35 /*
36 **	lib_unget_wch.c
37 **
38 **	The routine unget_wch().
39 **
40 */
41 
42 #include <curses.priv.h>
43 
44 MODULE_ID("$Id: lib_unget_wch.c,v 1.1 2010/09/06 17:26:17 nicm Exp $")
45 
46 /*
47  * Wrapper for wcrtomb() which obtains the length needed for the given
48  * wide-character 'source'.
49  */
50 NCURSES_EXPORT(size_t)
51 _nc_wcrtomb(char *target, wchar_t source, mbstate_t * state)
52 {
53     int result;
54 
55     if (target == 0) {
56 	wchar_t temp[2];
57 	const wchar_t *tempp = temp;
58 	temp[0] = source;
59 	temp[1] = 0;
60 	result = wcsrtombs(NULL, &tempp, 0, state);
61     } else {
62 	result = wcrtomb(target, source, state);
63     }
64     if (!isEILSEQ(result) && (result == 0))
65 	result = 1;
66     return result;
67 }
68 
69 NCURSES_EXPORT(int)
70 unget_wch(const wchar_t wch)
71 {
72     int result = OK;
73     mbstate_t state;
74     size_t length;
75     int n;
76 
77     T((T_CALLED("unget_wch(%#lx)"), (unsigned long) wch));
78 
79     init_mb(state);
80     length = _nc_wcrtomb(0, wch, &state);
81 
82     if (length != (size_t) (-1)
83 	&& length != 0) {
84 	char *string;
85 
86 	if ((string = (char *) malloc(length)) != 0) {
87 	    init_mb(state);
88 	    wcrtomb(string, wch, &state);
89 
90 	    for (n = (int) (length - 1); n >= 0; --n) {
91 		if (_nc_ungetch(SP, string[n]) != OK) {
92 		    result = ERR;
93 		    break;
94 		}
95 	    }
96 	    free(string);
97 	} else {
98 	    result = ERR;
99 	}
100     } else {
101 	result = ERR;
102     }
103 
104     returnCode(result);
105 }
106