commit d7e604f226a74e6a0b57382cedf687d651c3ca5e
parent c8831e052173e6eb637b33d95d6dacd22f7d3e39
Author: Antoine A <>
Date: Wed, 1 Dec 2021 20:15:27 +0100
Remove internal enum
reduce packed char memory layout to a single u8
Diffstat:
| M | uri-pack/src/lib.rs | | | 158 | ++++++++++++++----------------------------------------------------------------- |
1 file changed, 28 insertions(+), 130 deletions(-)
diff --git a/uri-pack/src/lib.rs b/uri-pack/src/lib.rs
@@ -1,139 +1,37 @@
-/// Reserved 5 bit code for extended packing
-const EXTENDED: u8 = 31;
-
-/// Packed ascii as 5 or 11 bits
-#[derive(Debug, Clone, Copy)]
-pub enum Packed {
- Simple(u8), // u5: 0..32
- Extended(u8), // u6: 0..54
-}
-
/// Pack an URI ascii char
/// Panic if char not supported
-fn pack_ascii(c: u8) -> Packed {
- use Packed::{Extended as E, Simple as S};
+fn pack_ascii(c: u8) -> u8 {
[
- E(63),
- E(36),
- E(37),
- E(38),
- E(39),
- S(30),
- E(40),
- E(41),
- E(42),
- E(43),
- E(44),
- E(45),
- E(46),
- S(28),
- S(26),
- S(27),
- E(26),
- E(27),
- E(28),
- E(29),
- E(30),
- E(31),
- E(32),
- E(33),
- E(34),
- E(35),
- E(47),
- E(48),
- E(49),
- E(50),
- E(51),
- E(52),
- E(53),
- E(0),
- E(1),
- E(2),
- E(3),
- E(4),
- E(5),
- E(6),
- E(7),
- E(8),
- E(9),
- E(10),
- E(11),
- E(12),
- E(13),
- E(14),
- E(15),
- E(16),
- E(17),
- E(18),
- E(19),
- E(20),
- E(21),
- E(22),
- E(23),
- E(24),
- E(25),
- E(54),
- E(55),
- E(56),
- E(57),
- S(29),
- E(58),
- S(0),
- S(1),
- S(2),
- S(3),
- S(4),
- S(5),
- S(6),
- S(7),
- S(8),
- S(9),
- S(10),
- S(11),
- S(12),
- S(13),
- S(14),
- S(15),
- S(16),
- S(17),
- S(18),
- S(19),
- S(20),
- S(21),
- S(22),
- S(23),
- S(24),
- S(25),
- E(59),
- E(60),
- E(61),
- E(62),
+ 94, 67, 68, 69, 70, 30, 71, 72, 73, 74, 75, 76, 77, 28, 26, 27, 57, 58, 59, 60, 61, 62, 63,
+ 64, 65, 66, 78, 79, 80, 81, 82, 83, 84, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 85, 86, 87, 88, 29, 89, 0, 1, 2, 3, 4,
+ 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 90, 91, 92,
+ 93,
][(c - b' ') as usize]
}
/// Unpack an URI ascii char
/// Panic if char not supported
-fn unpack_ascii(c: Packed) -> u8 {
- match c {
- Packed::Simple(c) => [
- b'a', b'b', b'c', b'd', b'e', b'f', b'g', b'h', b'i', b'j', b'k', b'l', b'm', b'n',
- b'o', b'p', b'q', b'r', b's', b't', b'u', b'v', b'w', b'x', b'y', b'z', b'.', b'/',
- b'-', b'_', b'%',
- ][c as usize],
- Packed::Extended(c) => [
- b'A', b'B', b'C', b'D', b'E', b'F', b'G', b'H', b'I', b'J', b'K', b'L', b'M', b'N',
- b'O', b'P', b'Q', b'R', b'S', b'T', b'U', b'V', b'W', b'X', b'Y', b'Z', b'0', b'1',
- b'2', b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'!', b'"', b'#', b'$', b'&', b'\'',
- b'(', b')', b'*', b'+', b',', b':', b';', b'<', b'=', b'>', b'?', b'@', b'[', b'\\',
- b']', b'^', b'`', b'{', b'|', b'}', b'~', b' ',
- ][c as usize],
- }
+fn unpack_ascii(c: u8) -> u8 {
+ [
+ b'a', b'b', b'c', b'd', b'e', b'f', b'g', b'h', b'i', b'j', b'k', b'l', b'm', b'n', b'o',
+ b'p', b'q', b'r', b's', b't', b'u', b'v', b'w', b'x', b'y', b'z', b'.', b'/', b'-', b'_',
+ b'%', b'A', b'B', b'C', b'D', b'E', b'F', b'G', b'H', b'I', b'J', b'K', b'L', b'M', b'N',
+ b'O', b'P', b'Q', b'R', b'S', b'T', b'U', b'V', b'W', b'X', b'Y', b'Z', b'0', b'1', b'2',
+ b'3', b'4', b'5', b'6', b'7', b'8', b'9', b'!', b'"', b'#', b'$', b'&', b'\'', b'(', b')',
+ b'*', b'+', b',', b':', b';', b'<', b'=', b'>', b'?', b'@', b'[', b'\\', b']', b'^', b'`',
+ b'{', b'|', b'}', b'~', b' ',
+ ][c as usize]
}
+
/// Check if an ascii char is packable
fn supported_ascii(c: &u8) -> bool {
(b' '..=b'~').contains(c)
}
+/// Extended packing limit
+const EXTENDED: u8 = 31;
+
#[derive(Debug, Clone, Copy, thiserror::Error)]
pub enum EncodeErr {
#[error("{0} is not a valid uri char")]
@@ -210,12 +108,12 @@ pub fn pack_uri(uri: &str) -> Result<(Vec<u8>, usize), EncodeErr> {
};
for c in uri.bytes() {
- match pack_ascii(c) {
- Packed::Simple(nb) => write_bits(nb, 5),
- Packed::Extended(nb) => {
- write_bits(EXTENDED, 5);
- write_bits(nb, 6);
- }
+ let nb = pack_ascii(c);
+ if nb < EXTENDED {
+ write_bits(nb, 5)
+ } else {
+ write_bits(EXTENDED, 5);
+ write_bits(nb - EXTENDED, 6);
}
}
@@ -279,8 +177,8 @@ pub fn unpack_uri(bytes: &[u8], len: usize) -> Result<String, DecodeErr> {
for _ in 0..len {
let encoded = match read_nb(5)? {
- EXTENDED => Packed::Extended(read_nb(6)?),
- nb => Packed::Simple(nb),
+ EXTENDED => read_nb(6)? + EXTENDED,
+ nb => nb,
};
buf.push(unpack_ascii(encoded) as char);
}
