Add Gnulib maintainer modules.
[bpt/guile.git] / lib / unistr / u8-mbtouc-unsafe-aux.c
1 /* Conversion UTF-8 to UCS-4.
2 Copyright (C) 2001-2002, 2006-2007, 2009 Free Software Foundation, Inc.
3 Written by Bruno Haible <bruno@clisp.org>, 2001.
4
5 This program is free software: you can redistribute it and/or modify it
6 under the terms of the GNU Lesser General Public License as published
7 by the Free Software Foundation; either version 3 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program. If not, see <http://www.gnu.org/licenses/>. */
17
18 #include <config.h>
19
20 /* Specification. */
21 #include "unistr.h"
22
23 #if defined IN_LIBUNISTRING || HAVE_INLINE
24
25 int
26 u8_mbtouc_unsafe_aux (ucs4_t *puc, const uint8_t *s, size_t n)
27 {
28 uint8_t c = *s;
29
30 if (c >= 0xc2)
31 {
32 if (c < 0xe0)
33 {
34 if (n >= 2)
35 {
36 #if CONFIG_UNICODE_SAFETY
37 if ((s[1] ^ 0x80) < 0x40)
38 #endif
39 {
40 *puc = ((unsigned int) (c & 0x1f) << 6)
41 | (unsigned int) (s[1] ^ 0x80);
42 return 2;
43 }
44 /* invalid multibyte character */
45 }
46 else
47 {
48 /* incomplete multibyte character */
49 *puc = 0xfffd;
50 return n;
51 }
52 }
53 else if (c < 0xf0)
54 {
55 if (n >= 3)
56 {
57 #if CONFIG_UNICODE_SAFETY
58 if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
59 && (c >= 0xe1 || s[1] >= 0xa0)
60 && (c != 0xed || s[1] < 0xa0))
61 #endif
62 {
63 *puc = ((unsigned int) (c & 0x0f) << 12)
64 | ((unsigned int) (s[1] ^ 0x80) << 6)
65 | (unsigned int) (s[2] ^ 0x80);
66 return 3;
67 }
68 /* invalid multibyte character */
69 }
70 else
71 {
72 /* incomplete multibyte character */
73 *puc = 0xfffd;
74 return n;
75 }
76 }
77 else if (c < 0xf8)
78 {
79 if (n >= 4)
80 {
81 #if CONFIG_UNICODE_SAFETY
82 if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
83 && (s[3] ^ 0x80) < 0x40
84 && (c >= 0xf1 || s[1] >= 0x90)
85 #if 1
86 && (c < 0xf4 || (c == 0xf4 && s[1] < 0x90))
87 #endif
88 )
89 #endif
90 {
91 *puc = ((unsigned int) (c & 0x07) << 18)
92 | ((unsigned int) (s[1] ^ 0x80) << 12)
93 | ((unsigned int) (s[2] ^ 0x80) << 6)
94 | (unsigned int) (s[3] ^ 0x80);
95 return 4;
96 }
97 /* invalid multibyte character */
98 }
99 else
100 {
101 /* incomplete multibyte character */
102 *puc = 0xfffd;
103 return n;
104 }
105 }
106 #if 0
107 else if (c < 0xfc)
108 {
109 if (n >= 5)
110 {
111 #if CONFIG_UNICODE_SAFETY
112 if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
113 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
114 && (c >= 0xf9 || s[1] >= 0x88))
115 #endif
116 {
117 *puc = ((unsigned int) (c & 0x03) << 24)
118 | ((unsigned int) (s[1] ^ 0x80) << 18)
119 | ((unsigned int) (s[2] ^ 0x80) << 12)
120 | ((unsigned int) (s[3] ^ 0x80) << 6)
121 | (unsigned int) (s[4] ^ 0x80);
122 return 5;
123 }
124 /* invalid multibyte character */
125 }
126 else
127 {
128 /* incomplete multibyte character */
129 *puc = 0xfffd;
130 return n;
131 }
132 }
133 else if (c < 0xfe)
134 {
135 if (n >= 6)
136 {
137 #if CONFIG_UNICODE_SAFETY
138 if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
139 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
140 && (s[5] ^ 0x80) < 0x40
141 && (c >= 0xfd || s[1] >= 0x84))
142 #endif
143 {
144 *puc = ((unsigned int) (c & 0x01) << 30)
145 | ((unsigned int) (s[1] ^ 0x80) << 24)
146 | ((unsigned int) (s[2] ^ 0x80) << 18)
147 | ((unsigned int) (s[3] ^ 0x80) << 12)
148 | ((unsigned int) (s[4] ^ 0x80) << 6)
149 | (unsigned int) (s[5] ^ 0x80);
150 return 6;
151 }
152 /* invalid multibyte character */
153 }
154 else
155 {
156 /* incomplete multibyte character */
157 *puc = 0xfffd;
158 return n;
159 }
160 }
161 #endif
162 }
163 /* invalid multibyte character */
164 *puc = 0xfffd;
165 return 1;
166 }
167
168 #endif