1 //! Convert a string in IBM codepage 437 to UTF-8
2
3 /// Trait to convert IBM codepage 437 to the target type
4 pub trait FromCp437 {
5 /// Target type
6 type Target;
7
8 /// Function that does the conversion from cp437.
9 /// Gennerally allocations will be avoided if all data falls into the ASCII range.
from_cp437(self) -> Self::Target10 fn from_cp437(self) -> Self::Target;
11 }
12
13 impl<'a> FromCp437 for &'a [u8] {
14 type Target = ::std::borrow::Cow<'a, str>;
15
from_cp437(self) -> Self::Target16 fn from_cp437(self) -> Self::Target {
17 if self.iter().all(|c| *c < 0x80) {
18 ::std::str::from_utf8(self).unwrap().into()
19 } else {
20 self.iter().map(|c| to_char(*c)).collect::<String>().into()
21 }
22 }
23 }
24
25 impl FromCp437 for Vec<u8> {
26 type Target = String;
27
from_cp437(self) -> Self::Target28 fn from_cp437(self) -> Self::Target {
29 if self.iter().all(|c| *c < 0x80) {
30 String::from_utf8(self).unwrap()
31 } else {
32 self.into_iter().map(to_char).collect()
33 }
34 }
35 }
36
to_char(input: u8) -> char37 fn to_char(input: u8) -> char {
38 let output = match input {
39 0x00..=0x7f => input as u32,
40 0x80 => 0x00c7,
41 0x81 => 0x00fc,
42 0x82 => 0x00e9,
43 0x83 => 0x00e2,
44 0x84 => 0x00e4,
45 0x85 => 0x00e0,
46 0x86 => 0x00e5,
47 0x87 => 0x00e7,
48 0x88 => 0x00ea,
49 0x89 => 0x00eb,
50 0x8a => 0x00e8,
51 0x8b => 0x00ef,
52 0x8c => 0x00ee,
53 0x8d => 0x00ec,
54 0x8e => 0x00c4,
55 0x8f => 0x00c5,
56 0x90 => 0x00c9,
57 0x91 => 0x00e6,
58 0x92 => 0x00c6,
59 0x93 => 0x00f4,
60 0x94 => 0x00f6,
61 0x95 => 0x00f2,
62 0x96 => 0x00fb,
63 0x97 => 0x00f9,
64 0x98 => 0x00ff,
65 0x99 => 0x00d6,
66 0x9a => 0x00dc,
67 0x9b => 0x00a2,
68 0x9c => 0x00a3,
69 0x9d => 0x00a5,
70 0x9e => 0x20a7,
71 0x9f => 0x0192,
72 0xa0 => 0x00e1,
73 0xa1 => 0x00ed,
74 0xa2 => 0x00f3,
75 0xa3 => 0x00fa,
76 0xa4 => 0x00f1,
77 0xa5 => 0x00d1,
78 0xa6 => 0x00aa,
79 0xa7 => 0x00ba,
80 0xa8 => 0x00bf,
81 0xa9 => 0x2310,
82 0xaa => 0x00ac,
83 0xab => 0x00bd,
84 0xac => 0x00bc,
85 0xad => 0x00a1,
86 0xae => 0x00ab,
87 0xaf => 0x00bb,
88 0xb0 => 0x2591,
89 0xb1 => 0x2592,
90 0xb2 => 0x2593,
91 0xb3 => 0x2502,
92 0xb4 => 0x2524,
93 0xb5 => 0x2561,
94 0xb6 => 0x2562,
95 0xb7 => 0x2556,
96 0xb8 => 0x2555,
97 0xb9 => 0x2563,
98 0xba => 0x2551,
99 0xbb => 0x2557,
100 0xbc => 0x255d,
101 0xbd => 0x255c,
102 0xbe => 0x255b,
103 0xbf => 0x2510,
104 0xc0 => 0x2514,
105 0xc1 => 0x2534,
106 0xc2 => 0x252c,
107 0xc3 => 0x251c,
108 0xc4 => 0x2500,
109 0xc5 => 0x253c,
110 0xc6 => 0x255e,
111 0xc7 => 0x255f,
112 0xc8 => 0x255a,
113 0xc9 => 0x2554,
114 0xca => 0x2569,
115 0xcb => 0x2566,
116 0xcc => 0x2560,
117 0xcd => 0x2550,
118 0xce => 0x256c,
119 0xcf => 0x2567,
120 0xd0 => 0x2568,
121 0xd1 => 0x2564,
122 0xd2 => 0x2565,
123 0xd3 => 0x2559,
124 0xd4 => 0x2558,
125 0xd5 => 0x2552,
126 0xd6 => 0x2553,
127 0xd7 => 0x256b,
128 0xd8 => 0x256a,
129 0xd9 => 0x2518,
130 0xda => 0x250c,
131 0xdb => 0x2588,
132 0xdc => 0x2584,
133 0xdd => 0x258c,
134 0xde => 0x2590,
135 0xdf => 0x2580,
136 0xe0 => 0x03b1,
137 0xe1 => 0x00df,
138 0xe2 => 0x0393,
139 0xe3 => 0x03c0,
140 0xe4 => 0x03a3,
141 0xe5 => 0x03c3,
142 0xe6 => 0x00b5,
143 0xe7 => 0x03c4,
144 0xe8 => 0x03a6,
145 0xe9 => 0x0398,
146 0xea => 0x03a9,
147 0xeb => 0x03b4,
148 0xec => 0x221e,
149 0xed => 0x03c6,
150 0xee => 0x03b5,
151 0xef => 0x2229,
152 0xf0 => 0x2261,
153 0xf1 => 0x00b1,
154 0xf2 => 0x2265,
155 0xf3 => 0x2264,
156 0xf4 => 0x2320,
157 0xf5 => 0x2321,
158 0xf6 => 0x00f7,
159 0xf7 => 0x2248,
160 0xf8 => 0x00b0,
161 0xf9 => 0x2219,
162 0xfa => 0x00b7,
163 0xfb => 0x221a,
164 0xfc => 0x207f,
165 0xfd => 0x00b2,
166 0xfe => 0x25a0,
167 0xff => 0x00a0,
168 };
169 ::std::char::from_u32(output).unwrap()
170 }
171
172 #[cfg(test)]
173 mod test {
174 #[test]
to_char_valid()175 fn to_char_valid() {
176 for i in 0x00_u32..0x100 {
177 super::to_char(i as u8);
178 }
179 }
180
181 #[test]
ascii()182 fn ascii() {
183 for i in 0x00..0x80 {
184 assert_eq!(super::to_char(i), i as char);
185 }
186 }
187
188 #[test]
example_slice()189 fn example_slice() {
190 use super::FromCp437;
191 let data = b"Cura\x87ao";
192 assert!(::std::str::from_utf8(data).is_err());
193 assert_eq!(data.from_cp437(), "Curaçao");
194 }
195
196 #[test]
example_vec()197 fn example_vec() {
198 use super::FromCp437;
199 let data = vec![0xCC, 0xCD, 0xCD, 0xB9];
200 assert!(String::from_utf8(data.clone()).is_err());
201 assert_eq!(&data.from_cp437(), "╠══╣");
202 }
203 }
204