1 /* Determine the number of screen columns needed for a string.
2 Copyright (C) 2000-2008 Free Software Foundation, Inc.
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17 /* Written by Bruno Haible <haible@clisp.cons.org>. */
32 /* Get mbstate_t, mbrtowc(), mbsinit(), wcwidth(). */
38 /* Returns the number of columns needed to represent the multibyte
39 character string pointed to by STRING. If a non-printable character
40 occurs, and MBSW_REJECT_UNPRINTABLE is specified, -1 is returned.
41 With flags = MBSW_REJECT_INVALID | MBSW_REJECT_UNPRINTABLE, this is
42 the multibyte analogue of the wcswidth function.
43 If STRING is not of length < INT_MAX / 2, integer overflow can occur. */
45 mbswidth (const char *string, int flags)
47 return mbsnwidth (string, strlen (string), flags);
50 /* Returns the number of columns needed to represent the multibyte
51 character string pointed to by STRING of length NBYTES. If a
52 non-printable character occurs, and MBSW_REJECT_UNPRINTABLE is
53 specified, -1 is returned.
54 If NBYTES is not < INT_MAX / 2, integer overflow can occur. */
56 mbsnwidth (const char *string, size_t nbytes, int flags)
58 const char *p = string;
59 const char *plimit = p + nbytes;
68 case ' ': case '!': case '"': case '#': case '%':
69 case '&': case '\'': case '(': case ')': case '*':
70 case '+': case ',': case '-': case '.': case '/':
71 case '0': case '1': case '2': case '3': case '4':
72 case '5': case '6': case '7': case '8': case '9':
73 case ':': case ';': case '<': case '=': case '>':
75 case 'A': case 'B': case 'C': case 'D': case 'E':
76 case 'F': case 'G': case 'H': case 'I': case 'J':
77 case 'K': case 'L': case 'M': case 'N': case 'O':
78 case 'P': case 'Q': case 'R': case 'S': case 'T':
79 case 'U': case 'V': case 'W': case 'X': case 'Y':
81 case '[': case '\\': case ']': case '^': case '_':
82 case 'a': case 'b': case 'c': case 'd': case 'e':
83 case 'f': case 'g': case 'h': case 'i': case 'j':
84 case 'k': case 'l': case 'm': case 'n': case 'o':
85 case 'p': case 'q': case 'r': case 's': case 't':
86 case 'u': case 'v': case 'w': case 'x': case 'y':
87 case 'z': case '{': case '|': case '}': case '~':
88 /* These characters are printable ASCII characters. */
93 /* If we have a multibyte sequence, scan it up to its end. */
96 memset (&mbstate, 0, sizeof mbstate);
103 bytes = mbrtowc (&wc, p, plimit - p, &mbstate);
105 if (bytes == (size_t) -1)
106 /* An invalid multibyte sequence was encountered. */
108 if (!(flags & MBSW_REJECT_INVALID))
118 if (bytes == (size_t) -2)
119 /* An incomplete multibyte character at the end. */
121 if (!(flags & MBSW_REJECT_INVALID))
132 /* A null wide character was encountered. */
137 /* A printable multibyte character. */
140 /* An unprintable multibyte character. */
141 if (!(flags & MBSW_REJECT_UNPRINTABLE))
142 width += (iswcntrl (wc) ? 0 : 1);
148 while (! mbsinit (&mbstate));
157 unsigned char c = (unsigned char) *p++;
161 else if (!(flags & MBSW_REJECT_UNPRINTABLE))
162 width += (iscntrl (c) ? 0 : 1);