1 /* Determine the number of screen columns needed for a string.
2 Copyright (C) 2000-2005 Free Software Foundation, Inc.
3
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 2, or (at your option)
7 any later version.
8
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.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
17
18 /* Written by Bruno Haible <haible@clisp.cons.org>. */
19
20 #ifdef HAVE_CONFIG_H
21 # include <config.h>
22 #endif
23
24 /* Specification. */
25 #include "mbswidth.h"
26
27 /* Get MB_CUR_MAX. */
28 #include <stdlib.h>
29
30 #include <string.h>
31
32 /* Get isprint(). */
33 #include <ctype.h>
34
35 /* Get mbstate_t, mbrtowc(), mbsinit(), wcwidth(). */
36 #if HAVE_WCHAR_H
37 /* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
38 <wchar.h>.
39 BSD/OS 4.1 has a bug: <stdio.h> and <time.h> must be included before
40 <wchar.h>. */
41 # include <stdio.h>
42 # include <time.h>
43 # include <wchar.h>
44 #endif
45
46 /* Get iswprint(), iswcntrl(). */
47 #if HAVE_WCTYPE_H
48 # include <wctype.h>
49 #endif
50 #if !defined iswprint && !HAVE_ISWPRINT
51 # define iswprint(wc) 1
52 #endif
53 #if !defined iswcntrl && !HAVE_ISWCNTRL
54 # define iswcntrl(wc) 0
55 #endif
56
57 #ifndef mbsinit
58 # if !HAVE_MBSINIT
59 # define mbsinit(ps) 1
60 # endif
61 #endif
62
63 #ifndef HAVE_DECL_WCWIDTH
64 "this configure-time declaration test was not run"
65 #endif
66 #if !HAVE_DECL_WCWIDTH
67 int wcwidth ();
68 #endif
69
70 #ifndef wcwidth
71 # if !HAVE_WCWIDTH
72 /* wcwidth doesn't exist, so assume all printable characters have
73 width 1. */
74 # define wcwidth(wc) ((wc) == 0 ? 0 : iswprint (wc) ? 1 : -1)
75 # endif
76 #endif
77
78 /* Get ISPRINT. */
79 #if defined (STDC_HEADERS) || (!defined (isascii) && !defined (HAVE_ISASCII))
80 # define IN_CTYPE_DOMAIN(c) 1
81 #else
82 # define IN_CTYPE_DOMAIN(c) isascii(c)
83 #endif
84 /* Undefine to protect against the definition in wctype.h of Solaris 2.6. */
85 #undef ISPRINT
86 #define ISPRINT(c) (IN_CTYPE_DOMAIN (c) && isprint (c))
87 #undef ISCNTRL
88 #define ISCNTRL(c) (IN_CTYPE_DOMAIN (c) && iscntrl (c))
89
90 /* Returns the number of columns needed to represent the multibyte
91 character string pointed to by STRING. If a non-printable character
92 occurs, and MBSW_REJECT_UNPRINTABLE is specified, -1 is returned.
93 With flags = MBSW_REJECT_INVALID | MBSW_REJECT_UNPRINTABLE, this is
94 the multibyte analogue of the wcswidth function.
95 If STRING is not of length < INT_MAX / 2, integer overflow can occur. */
96 int
mbswidth(const char * string,int flags)97 mbswidth (const char *string, int flags)
98 {
99 return mbsnwidth (string, strlen (string), flags);
100 }
101
102 /* Returns the number of columns needed to represent the multibyte
103 character string pointed to by STRING of length NBYTES. If a
104 non-printable character occurs, and MBSW_REJECT_UNPRINTABLE is
105 specified, -1 is returned.
106 If NBYTES is not < INT_MAX / 2, integer overflow can occur. */
107 int
mbsnwidth(const char * string,size_t nbytes,int flags)108 mbsnwidth (const char *string, size_t nbytes, int flags)
109 {
110 const char *p = string;
111 const char *plimit = p + nbytes;
112 int width;
113
114 width = 0;
115 #if HAVE_MBRTOWC
116 if (MB_CUR_MAX > 1)
117 {
118 while (p < plimit)
119 switch (*p)
120 {
121 case ' ': case '!': case '"': case '#': case '%':
122 case '&': case '\'': case '(': case ')': case '*':
123 case '+': case ',': case '-': case '.': case '/':
124 case '0': case '1': case '2': case '3': case '4':
125 case '5': case '6': case '7': case '8': case '9':
126 case ':': case ';': case '<': case '=': case '>':
127 case '?':
128 case 'A': case 'B': case 'C': case 'D': case 'E':
129 case 'F': case 'G': case 'H': case 'I': case 'J':
130 case 'K': case 'L': case 'M': case 'N': case 'O':
131 case 'P': case 'Q': case 'R': case 'S': case 'T':
132 case 'U': case 'V': case 'W': case 'X': case 'Y':
133 case 'Z':
134 case '[': case '\\': case ']': case '^': case '_':
135 case 'a': case 'b': case 'c': case 'd': case 'e':
136 case 'f': case 'g': case 'h': case 'i': case 'j':
137 case 'k': case 'l': case 'm': case 'n': case 'o':
138 case 'p': case 'q': case 'r': case 's': case 't':
139 case 'u': case 'v': case 'w': case 'x': case 'y':
140 case 'z': case '{': case '|': case '}': case '~':
141 /* These characters are printable ASCII characters. */
142 p++;
143 width++;
144 break;
145 default:
146 /* If we have a multibyte sequence, scan it up to its end. */
147 {
148 mbstate_t mbstate;
149 memset (&mbstate, 0, sizeof mbstate);
150 do
151 {
152 wchar_t wc;
153 size_t bytes;
154 int w;
155
156 bytes = mbrtowc (&wc, p, plimit - p, &mbstate);
157
158 if (bytes == (size_t) -1)
159 /* An invalid multibyte sequence was encountered. */
160 {
161 if (!(flags & MBSW_REJECT_INVALID))
162 {
163 p++;
164 width++;
165 break;
166 }
167 else
168 return -1;
169 }
170
171 if (bytes == (size_t) -2)
172 /* An incomplete multibyte character at the end. */
173 {
174 if (!(flags & MBSW_REJECT_INVALID))
175 {
176 p = plimit;
177 width++;
178 break;
179 }
180 else
181 return -1;
182 }
183
184 if (bytes == 0)
185 /* A null wide character was encountered. */
186 bytes = 1;
187
188 w = wcwidth (wc);
189 if (w >= 0)
190 /* A printable multibyte character. */
191 width += w;
192 else
193 /* An unprintable multibyte character. */
194 if (!(flags & MBSW_REJECT_UNPRINTABLE))
195 width += (iswcntrl (wc) ? 0 : 1);
196 else
197 return -1;
198
199 p += bytes;
200 }
201 while (! mbsinit (&mbstate));
202 }
203 break;
204 }
205 return width;
206 }
207 #endif
208
209 while (p < plimit)
210 {
211 unsigned char c = (unsigned char) *p++;
212
213 if (ISPRINT (c))
214 width++;
215 else if (!(flags & MBSW_REJECT_UNPRINTABLE))
216 width += (ISCNTRL (c) ? 0 : 1);
217 else
218 return -1;
219 }
220 return width;
221 }
222