1 /****************************************************************************
2 * Copyright 2020,2021 Thomas E. Dickey *
3 * Copyright 2002-2011,2016 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 *
8 * without limitation the rights to use, copy, modify, merge, publish, *
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. *
19 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, *
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 /****************************************************************************
31 * Author: Thomas E. Dickey 2002-on *
32 ****************************************************************************/
33
34 /*
35 ** lib_get_wch.c
36 **
37 ** The routine get_wch().
38 **
39 */
40
41 #include <curses.priv.h>
42 #include <ctype.h>
43
44 MODULE_ID("$Id: lib_get_wch.c,v 1.26 2021/04/17 16:12:54 tom Exp $")
45
NCURSES_EXPORT(int)46 NCURSES_EXPORT(int)
47 wget_wch(WINDOW *win, wint_t *result)
48 {
49 SCREEN *sp;
50 int code;
51 int value = 0;
52 #ifndef state_unused
53 mbstate_t state;
54 #endif
55
56 T((T_CALLED("wget_wch(%p)"), (void *) win));
57
58 /*
59 * We can get a stream of single-byte characters and KEY_xxx codes from
60 * _nc_wgetch(), while we want to return a wide character or KEY_xxx code.
61 */
62 _nc_lock_global(curses);
63 sp = _nc_screen_of(win);
64
65 if (sp != 0) {
66 size_t count = 0;
67
68 for (;;) {
69 char buffer[(MB_LEN_MAX * 9) + 1]; /* allow some redundant shifts */
70
71 T(("reading %d of %d", (int) count + 1, (int) sizeof(buffer)));
72 code = _nc_wgetch(win, &value, TRUE EVENTLIST_2nd((_nc_eventlist
73 *) 0));
74 if (code == ERR) {
75 break;
76 } else if (code == KEY_CODE_YES) {
77 /*
78 * If we were processing an incomplete multibyte character,
79 * return an error since we have a KEY_xxx code which
80 * interrupts it. For some cases, we could improve this by
81 * writing a new version of lib_getch.c(!), but it is not clear
82 * whether the improvement would be worth the effort.
83 */
84 if (count != 0) {
85 safe_ungetch(SP_PARM, value);
86 code = ERR;
87 }
88 break;
89 } else if (count + 1 >= sizeof(buffer)) {
90 safe_ungetch(SP_PARM, value);
91 code = ERR;
92 break;
93 } else {
94 int status;
95
96 buffer[count++] = (char) UChar(value);
97 reset_mbytes(state);
98 status = count_mbytes(buffer, count, state);
99 if (status >= 0) {
100 wchar_t wch;
101 reset_mbytes(state);
102 if (check_mbytes(wch, buffer, count, state) != status) {
103 code = ERR; /* the two calls should match */
104 safe_ungetch(SP_PARM, value);
105 }
106 value = wch;
107 break;
108 }
109 }
110 }
111 } else {
112 code = ERR;
113 }
114
115 if (result != 0)
116 *result = (wint_t) value;
117
118 _nc_unlock_global(curses);
119 T(("result %#o", value));
120 returnCode(code);
121 }
122