xref: /freebsd/contrib/ncurses/ncurses/widechar/lib_unget_wch.c (revision ae83180158c4c937f170e31eff311b18c0286a93)
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2  * Copyright (c) 2002 Free Software Foundation, Inc.                        *
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28 
29 /****************************************************************************
30  *  Author: Thomas E. Dickey 2002                                           *
31  ****************************************************************************/
32 
33 /*
34 **	lib_unget_wch.c
35 **
36 **	The routine unget_wch().
37 **
38 */
39 
40 #include <curses.priv.h>
41 
42 MODULE_ID("$Id: lib_unget_wch.c,v 1.2 2002/03/17 00:01:38 tom Exp $")
43 
44 NCURSES_EXPORT(int)
45 unget_wch(const wchar_t wch)
46 {
47     int result = OK;
48     mbstate_t state;
49     size_t length;
50     int n;
51 
52     T((T_CALLED("unget_wch(%d)"), wch));
53 
54     memset(&state, 0, sizeof(state));
55     length = wcrtomb(0, wch, &state);
56 
57     if (length != (size_t) (-1)
58 	&& length != 0) {
59 	char *string = malloc(length);
60 
61 	memset(&state, 0, sizeof(state));
62 	wcrtomb(string, wch, &state);
63 
64 	for (n = (int) (length - 1); n >= 0; --n) {
65 	    if (ungetch(string[n]) != OK) {
66 		result = ERR;
67 		break;
68 	    }
69 	}
70 	free(string);
71     } else {
72 	result = ERR;
73     }
74 
75     returnCode(result);
76 }
77