const USIZE_LEB128_SIZE: usize = 10;
macro_rules! leb128_size {
- (u16) => (3);
- (u32) => (5);
- (u64) => (10);
- (u128) => (19);
- (usize) => (USIZE_LEB128_SIZE);
+ (u16) => {
+ 3
+ };
+ (u32) => {
+ 5
+ };
+ (u64) => {
+ 10
+ };
+ (u128) => {
+ 19
+ };
+ (usize) => {
+ USIZE_LEB128_SIZE
+ };
}
macro_rules! impl_write_unsigned_leb128 {
- ($fn_name:ident, $int_ty:ident) => (
+ ($fn_name:ident, $int_ty:ident) => {
#[inline]
pub fn $fn_name(out: &mut Vec<u8>, mut value: $int_ty) {
- for _ in 0 .. leb128_size!($int_ty) {
+ for _ in 0..leb128_size!($int_ty) {
let mut byte = (value & 0x7F) as u8;
value >>= 7;
if value != 0 {
}
}
}
- )
+ };
}
impl_write_unsigned_leb128!(write_u16_leb128, u16);
impl_write_unsigned_leb128!(write_u128_leb128, u128);
impl_write_unsigned_leb128!(write_usize_leb128, usize);
-
macro_rules! impl_read_unsigned_leb128 {
- ($fn_name:ident, $int_ty:ident) => (
+ ($fn_name:ident, $int_ty:ident) => {
#[inline]
pub fn $fn_name(slice: &[u8]) -> ($int_ty, usize) {
let mut result: $int_ty = 0;
let mut shift = 0;
let mut position = 0;
- for _ in 0 .. leb128_size!($int_ty) {
- let byte = unsafe {
- *slice.get_unchecked(position)
- };
+ for _ in 0..leb128_size!($int_ty) {
+ let byte = unsafe { *slice.get_unchecked(position) };
position += 1;
result |= ((byte & 0x7F) as $int_ty) << shift;
if (byte & 0x80) == 0 {
(result, position)
}
- )
+ };
}
impl_read_unsigned_leb128!(read_u16_leb128, u16);
impl_read_unsigned_leb128!(read_u128_leb128, u128);
impl_read_unsigned_leb128!(read_usize_leb128, usize);
-
-
#[inline]
/// encodes an integer using signed leb128 encoding and stores
/// the result using a callback function.
/// that is to be written to with the byte to be encoded
/// at that position.
pub fn write_signed_leb128_to<W>(mut value: i128, mut write: W)
- where W: FnMut(u8)
+where
+ W: FnMut(u8),
{
loop {
let mut byte = (value as u8) & 0x7f;
value >>= 7;
- let more = !(((value == 0) && ((byte & 0x40) == 0)) ||
- ((value == -1) && ((byte & 0x40) != 0)));
+ let more =
+ !(((value == 0) && ((byte & 0x40) == 0)) || ((value == -1) && ((byte & 0x40) != 0)));
if more {
byte |= 0x80; // Mark this byte to show that more bytes will follow.