1 /****************************************************************************
2  * Copyright 2018,2020 Thomas E. Dickey                                     *
3  * Copyright 2012,2013 Free Software Foundation, Inc.                       *
4  *                                                                          *
5  * Permission is hereby granted, free of charge, to any person obtaining a  *
6  * copy of this software and associated documentation files (the            *
7  * "Software"), to deal in the Software without restriction, including      *
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9  * distribute, distribute with modifications, sublicense, and/or sell       *
10  * copies of the Software, and to permit persons to whom the Software is    *
11  * furnished to do so, subject to the following conditions:                 *
12  *                                                                          *
13  * The above copyright notice and this permission notice shall be included  *
14  * in all copies or substantial portions of the Software.                   *
15  *                                                                          *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
18  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
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20  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
21  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
22  * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
23  *                                                                          *
24  * Except as contained in this notice, the name(s) of the above copyright   *
25  * holders shall not be used in advertising or otherwise to promote the     *
26  * sale, use or other dealings in this Software without prior written       *
27  * authorization.                                                           *
28  ****************************************************************************/
29 
30 #include <curses.priv.h>
31 
32 #if USE_WIDEC_SUPPORT
33 
34 MODULE_ID("$Id: widechars.c,v 1.7 2020/02/02 23:34:34 tom Exp $")
35 
36 #if defined(_WIN32)
37 /*
38  * MinGW has wide-character functions, but they do not work correctly.
39  */
40 
41 int
42 _nc_mbtowc(wchar_t *pwc, const char *s, size_t n)
43 {
44     int result;
45     int count;
46     int try;
47 
48     if (s != 0 && n != 0) {
49 	/*
50 	 * MultiByteToWideChar() can decide to return more than one
51 	 * wide-character.  We want only one.  Ignore any trailing null, both
52 	 * in the initial count and in the conversion.
53 	 */
54 	count = 0;
55 	for (try = 1; try <= (int) n; ++try) {
56 	    count = MultiByteToWideChar(CP_UTF8,
57 					MB_ERR_INVALID_CHARS,
58 					s,
59 					try,
60 					pwc,
61 					0);
62 	    TR(TRACE_BITS, ("...try %d:%d", try, count));
63 	    if (count > 0) {
64 		break;
65 	    }
66 	}
67 	if (count < 1 || count > 2) {
68 	    result = -1;
69 	} else {
70 	    wchar_t actual[2];
71 	    memset(&actual, 0, sizeof(actual));
72 	    count = MultiByteToWideChar(CP_UTF8,
73 					MB_ERR_INVALID_CHARS,
74 					s,
75 					try,
76 					actual,
77 					2);
78 	    TR(TRACE_BITS, ("\twin32 ->%#x, %#x", actual[0], actual[1]));
79 	    *pwc = actual[0];
80 	    if (actual[1] != 0)
81 		result = -1;
82 	    else
83 		result = try;
84 	}
85     } else {
86 	result = 0;
87     }
88 
89     return result;
90 }
91 
92 int
93 _nc_mblen(const char *s, size_t n)
94 {
95     int result = -1;
96     int count;
97     wchar_t temp;
98 
99     if (s != 0 && n != 0) {
100 	count = _nc_mbtowc(&temp, s, n);
101 	if (count == 1) {
102 	    int check = WideCharToMultiByte(CP_UTF8,
103 					    0,
104 					    &temp,
105 					    1,
106 					    NULL,
107 					    0,	/* compute length only */
108 					    NULL,
109 					    NULL);
110 	    TR(TRACE_BITS, ("\tcheck ->%d\n", check));
111 	    if (check > 0 && (size_t) check <= n) {
112 		result = check;
113 	    }
114 	}
115     } else {
116 	result = 0;
117     }
118 
119     return result;
120 }
121 
122 int __MINGW_NOTHROW
123 _nc_wctomb(char *s, wchar_t wc)
124 {
125     int result;
126     int check;
127 
128     check = WideCharToMultiByte(CP_UTF8,
129 				0,
130 				&wc,
131 				1,
132 				NULL,
133 				0,	/* compute length only */
134 				NULL,
135 				NULL);
136     if (check > 0) {
137 	result = WideCharToMultiByte(CP_UTF8,
138 				     0,
139 				     &wc,
140 				     1,
141 				     s,
142 				     check + 1,
143 				     NULL,
144 				     NULL);
145     } else {
146 	result = -1;
147     }
148     return result;
149 }
150 
151 #endif /* _WIN32 */
152 
153 #endif /* USE_WIDEC_SUPPORT */
154