(buf: &[u8])
| 12 | |
| 13 | |
| 14 | pub fn frombytes(buf: &[u8]) -> Result<Font, ()> |
| 15 | { |
| 16 | if buf.len() < 4 || buf[0] != 0x36 || buf[1] != 0x04 |
| 17 | { |
| 18 | return Err(()); |
| 19 | } |
| 20 | let mode = buf[2]; |
| 21 | let h = buf[3]; |
| 22 | let sz = match mode |
| 23 | { |
| 24 | 0 | 2 => 256, |
| 25 | 1 | 3 => 512, |
| 26 | _ => return Err(()), |
| 27 | }; |
| 28 | |
| 29 | let n = (4 + sz * h as u16) as usize; |
| 30 | if buf.len() < n |
| 31 | { |
| 32 | return Err(()); |
| 33 | } |
| 34 | let dat = buf[4..n].to_vec(); |
| 35 | |
| 36 | Ok(Font |
| 37 | { |
| 38 | h, |
| 39 | sz, |
| 40 | dat |
| 41 | }) |
| 42 | } |