1//! Convert a string in IBM codepage 437 to UTF-8
2
3/// Trait to convert IBM codepage 437 to the target type
4pub trait FromCp437 {
5 /// Target type
6 type Target;
7
8 /// Function that does the conversion from cp437.
9 /// Generally allocations will be avoided if all data falls into the ASCII range.
10 #[allow(clippy::wrong_self_convention)]
11 fn from_cp437(self) -> Self::Target;
12}
13
14impl<'a> FromCp437 for &'a [u8] {
15 type Target = ::std::borrow::Cow<'a, str>;
16
17 fn from_cp437(self) -> Self::Target {
18 if self.iter().all(|c: &u8| *c < 0x80) {
19 ::std::str::from_utf8(self).unwrap().into()
20 } else {
21 self.iter().map(|c: &u8| to_char(*c)).collect::<String>().into()
22 }
23 }
24}
25
26impl FromCp437 for Vec<u8> {
27 type Target = String;
28
29 fn from_cp437(self) -> Self::Target {
30 if self.iter().all(|c: &u8| *c < 0x80) {
31 String::from_utf8(self).unwrap()
32 } else {
33 self.into_iter().map(to_char).collect()
34 }
35 }
36}
37
38fn to_char(input: u8) -> char {
39 let output = match input {
40 0x00..=0x7f => input as u32,
41 0x80 => 0x00c7,
42 0x81 => 0x00fc,
43 0x82 => 0x00e9,
44 0x83 => 0x00e2,
45 0x84 => 0x00e4,
46 0x85 => 0x00e0,
47 0x86 => 0x00e5,
48 0x87 => 0x00e7,
49 0x88 => 0x00ea,
50 0x89 => 0x00eb,
51 0x8a => 0x00e8,
52 0x8b => 0x00ef,
53 0x8c => 0x00ee,
54 0x8d => 0x00ec,
55 0x8e => 0x00c4,
56 0x8f => 0x00c5,
57 0x90 => 0x00c9,
58 0x91 => 0x00e6,
59 0x92 => 0x00c6,
60 0x93 => 0x00f4,
61 0x94 => 0x00f6,
62 0x95 => 0x00f2,
63 0x96 => 0x00fb,
64 0x97 => 0x00f9,
65 0x98 => 0x00ff,
66 0x99 => 0x00d6,
67 0x9a => 0x00dc,
68 0x9b => 0x00a2,
69 0x9c => 0x00a3,
70 0x9d => 0x00a5,
71 0x9e => 0x20a7,
72 0x9f => 0x0192,
73 0xa0 => 0x00e1,
74 0xa1 => 0x00ed,
75 0xa2 => 0x00f3,
76 0xa3 => 0x00fa,
77 0xa4 => 0x00f1,
78 0xa5 => 0x00d1,
79 0xa6 => 0x00aa,
80 0xa7 => 0x00ba,
81 0xa8 => 0x00bf,
82 0xa9 => 0x2310,
83 0xaa => 0x00ac,
84 0xab => 0x00bd,
85 0xac => 0x00bc,
86 0xad => 0x00a1,
87 0xae => 0x00ab,
88 0xaf => 0x00bb,
89 0xb0 => 0x2591,
90 0xb1 => 0x2592,
91 0xb2 => 0x2593,
92 0xb3 => 0x2502,
93 0xb4 => 0x2524,
94 0xb5 => 0x2561,
95 0xb6 => 0x2562,
96 0xb7 => 0x2556,
97 0xb8 => 0x2555,
98 0xb9 => 0x2563,
99 0xba => 0x2551,
100 0xbb => 0x2557,
101 0xbc => 0x255d,
102 0xbd => 0x255c,
103 0xbe => 0x255b,
104 0xbf => 0x2510,
105 0xc0 => 0x2514,
106 0xc1 => 0x2534,
107 0xc2 => 0x252c,
108 0xc3 => 0x251c,
109 0xc4 => 0x2500,
110 0xc5 => 0x253c,
111 0xc6 => 0x255e,
112 0xc7 => 0x255f,
113 0xc8 => 0x255a,
114 0xc9 => 0x2554,
115 0xca => 0x2569,
116 0xcb => 0x2566,
117 0xcc => 0x2560,
118 0xcd => 0x2550,
119 0xce => 0x256c,
120 0xcf => 0x2567,
121 0xd0 => 0x2568,
122 0xd1 => 0x2564,
123 0xd2 => 0x2565,
124 0xd3 => 0x2559,
125 0xd4 => 0x2558,
126 0xd5 => 0x2552,
127 0xd6 => 0x2553,
128 0xd7 => 0x256b,
129 0xd8 => 0x256a,
130 0xd9 => 0x2518,
131 0xda => 0x250c,
132 0xdb => 0x2588,
133 0xdc => 0x2584,
134 0xdd => 0x258c,
135 0xde => 0x2590,
136 0xdf => 0x2580,
137 0xe0 => 0x03b1,
138 0xe1 => 0x00df,
139 0xe2 => 0x0393,
140 0xe3 => 0x03c0,
141 0xe4 => 0x03a3,
142 0xe5 => 0x03c3,
143 0xe6 => 0x00b5,
144 0xe7 => 0x03c4,
145 0xe8 => 0x03a6,
146 0xe9 => 0x0398,
147 0xea => 0x03a9,
148 0xeb => 0x03b4,
149 0xec => 0x221e,
150 0xed => 0x03c6,
151 0xee => 0x03b5,
152 0xef => 0x2229,
153 0xf0 => 0x2261,
154 0xf1 => 0x00b1,
155 0xf2 => 0x2265,
156 0xf3 => 0x2264,
157 0xf4 => 0x2320,
158 0xf5 => 0x2321,
159 0xf6 => 0x00f7,
160 0xf7 => 0x2248,
161 0xf8 => 0x00b0,
162 0xf9 => 0x2219,
163 0xfa => 0x00b7,
164 0xfb => 0x221a,
165 0xfc => 0x207f,
166 0xfd => 0x00b2,
167 0xfe => 0x25a0,
168 0xff => 0x00a0,
169 };
170 ::std::char::from_u32(output).unwrap()
171}
172
173#[cfg(test)]
174mod test {
175 #[test]
176 fn to_char_valid() {
177 for i in 0x00_u32..0x100 {
178 super::to_char(i as u8);
179 }
180 }
181
182 #[test]
183 fn ascii() {
184 for i in 0x00..0x80 {
185 assert_eq!(super::to_char(i), i as char);
186 }
187 }
188
189 #[test]
190 fn example_slice() {
191 use super::FromCp437;
192 let data = b"Cura\x87ao";
193 assert!(::std::str::from_utf8(data).is_err());
194 assert_eq!(data.from_cp437(), "Curaçao");
195 }
196
197 #[test]
198 fn example_vec() {
199 use super::FromCp437;
200 let data = vec![0xCC, 0xCD, 0xCD, 0xB9];
201 assert!(String::from_utf8(data.clone()).is_err());
202 assert_eq!(&data.from_cp437(), "╠══╣");
203 }
204}
205