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Indent macro body

This commit is contained in:
David Tolnay 2017-09-16 14:12:12 -07:00
parent 34bffe2943
commit 35106024c6
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1 changed files with 61 additions and 60 deletions
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121
src/lib.rs
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@ -40,76 +40,77 @@ const MAX_LEN: usize = 40; // i128::MIN (including minus sign)
// Adaptation of the original implementation at // Adaptation of the original implementation at
// https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L188-L266 // https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L188-L266
macro_rules! impl_Integer { macro_rules! impl_Integer {
($($t:ident),* as $conv_fn:ident) => ($( ($($t:ident),* as $conv_fn:ident) => {$(
impl Integer for $t { impl Integer for $t {
fn write<W: io::Write>(self, mut wr: W) -> io::Result<usize> { fn write<W: io::Write>(self, mut wr: W) -> io::Result<usize> {
let mut buf = unsafe { mem::uninitialized() }; let mut buf = unsafe { mem::uninitialized() };
let bytes = self.write_to(&mut buf); let bytes = self.write_to(&mut buf);
try!(wr.write_all(bytes)); try!(wr.write_all(bytes));
Ok(bytes.len()) Ok(bytes.len())
}
} }
}
impl IntegerPrivate for $t { impl IntegerPrivate for $t {
#[allow(unused_comparisons)] #[allow(unused_comparisons)]
fn write_to(self, buf: &mut [u8; MAX_LEN]) -> &[u8] { fn write_to(self, buf: &mut [u8; MAX_LEN]) -> &[u8] {
let is_nonnegative = self >= 0; let is_nonnegative = self >= 0;
let mut n = if is_nonnegative { let mut n = if is_nonnegative {
self as $conv_fn self as $conv_fn
} else { } else {
// convert the negative num to positive by summing 1 to it's 2 complement // convert the negative num to positive by summing 1 to it's 2 complement
(!(self as $conv_fn)).wrapping_add(1) (!(self as $conv_fn)).wrapping_add(1)
}; };
let mut curr = buf.len() as isize; let mut curr = buf.len() as isize;
let buf_ptr = buf.as_mut_ptr(); let buf_ptr = buf.as_mut_ptr();
let lut_ptr = DEC_DIGITS_LUT.as_ptr(); let lut_ptr = DEC_DIGITS_LUT.as_ptr();
unsafe { unsafe {
// eagerly decode 4 characters at a time // eagerly decode 4 characters at a time
if <$t>::max_value() as u64 >= 10000 { if <$t>::max_value() as u64 >= 10000 {
while n >= 10000 { while n >= 10000 {
let rem = (n % 10000) as isize; let rem = (n % 10000) as isize;
n /= 10000; n /= 10000;
let d1 = (rem / 100) << 1; let d1 = (rem / 100) << 1;
let d2 = (rem % 100) << 1; let d2 = (rem % 100) << 1;
curr -= 4; curr -= 4;
ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
ptr::copy_nonoverlapping(lut_ptr.offset(d2), buf_ptr.offset(curr + 2), 2);
}
}
// if we reach here numbers are <= 9999, so at most 4 chars long
let mut n = n as isize; // possibly reduce 64bit math
// decode 2 more chars, if > 2 chars
if n >= 100 {
let d1 = (n % 100) << 1;
n /= 100;
curr -= 2;
ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2); ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
ptr::copy_nonoverlapping(lut_ptr.offset(d2), buf_ptr.offset(curr + 2), 2); }
// decode last 1 or 2 chars
if n < 10 {
curr -= 1;
*buf_ptr.offset(curr) = (n as u8) + b'0';
} else {
let d1 = n << 1;
curr -= 2;
ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
}
if !is_nonnegative {
curr -= 1;
*buf_ptr.offset(curr) = b'-';
} }
} }
// if we reach here numbers are <= 9999, so at most 4 chars long let len = buf.len() - curr as usize;
let mut n = n as isize; // possibly reduce 64bit math unsafe { slice::from_raw_parts(buf_ptr.offset(curr), len) }
// decode 2 more chars, if > 2 chars
if n >= 100 {
let d1 = (n % 100) << 1;
n /= 100;
curr -= 2;
ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
}
// decode last 1 or 2 chars
if n < 10 {
curr -= 1;
*buf_ptr.offset(curr) = (n as u8) + b'0';
} else {
let d1 = n << 1;
curr -= 2;
ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2);
}
if !is_nonnegative {
curr -= 1;
*buf_ptr.offset(curr) = b'-';
}
} }
let len = buf.len() - curr as usize;
unsafe { slice::from_raw_parts(buf_ptr.offset(curr), len) }
} }
})*); )*};
} }
impl_Integer!(i8, u8, i16, u16, i32, u32 as u32); impl_Integer!(i8, u8, i16, u16, i32, u32 as u32);