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//! Minimal standard base64 for moving binary clipboard payloads across the JSON IPC boundary.
const ALPHA: &[u8; 64] = b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
pub fn encode(data: &[u8]) -> String {
let mut out = String::with_capacity(data.len().div_ceil(3) * 4);
for chunk in data.chunks(3) {
let n = (u32::from(chunk[0]) << 16)
| (u32::from(*chunk.get(1).unwrap_or(&0)) << 8)
| u32::from(*chunk.get(2).unwrap_or(&0));
out.push(ALPHA[(n >> 18) as usize & 63] as char);
out.push(ALPHA[(n >> 12) as usize & 63] as char);
out.push(if chunk.len() > 1 {
ALPHA[(n >> 6) as usize & 63] as char
} else {
'='
});
out.push(if chunk.len() > 2 {
ALPHA[n as usize & 63] as char
} else {
'='
});
}
out
}
pub fn decode(s: &str) -> Option<Vec<u8>> {
let mut out = Vec::with_capacity(s.len() / 4 * 3);
let (mut acc, mut bits) = (0u32, 0u32);
for c in s.bytes().filter(|c| !c.is_ascii_whitespace()) {
if c == b'=' {
break;
}
let v = ALPHA.iter().position(|a| *a == c)? as u32;
acc = (acc << 6) | v;
bits += 6;
if bits >= 8 {
bits -= 8;
out.push((acc >> bits) as u8);
acc &= (1 << bits) - 1;
}
}
Some(out)
}