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diff --git a/third_party/rust/encoding_rs/src/handles.rs b/third_party/rust/encoding_rs/src/handles.rs
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+// Copyright Mozilla Foundation. See the COPYRIGHT
+// file at the top-level directory of this distribution.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+//! This module provides structs that use lifetimes to couple bounds checking
+//! and space availability checking and detaching those from actual slice
+//! reading/writing.
+//!
+//! At present, the internals of the implementation are safe code, so the
+//! bound checks currently also happen on read/write. Once this code works,
+//! the plan is to replace the internals with unsafe code that omits the
+//! bound check at the read/write time.
+
+#[cfg(all(
+ feature = "simd-accel",
+ any(
+ target_feature = "sse2",
+ all(target_endian = "little", target_arch = "aarch64"),
+ all(target_endian = "little", target_feature = "neon")
+ )
+))]
+use crate::simd_funcs::*;
+
+#[cfg(all(
+ feature = "simd-accel",
+ any(
+ target_feature = "sse2",
+ all(target_endian = "little", target_arch = "aarch64"),
+ all(target_endian = "little", target_feature = "neon")
+ )
+))]
+use packed_simd::u16x8;
+
+use super::DecoderResult;
+use super::EncoderResult;
+use crate::ascii::*;
+use crate::utf_8::convert_utf8_to_utf16_up_to_invalid;
+use crate::utf_8::utf8_valid_up_to;
+
+pub enum Space<T> {
+ Available(T),
+ Full(usize),
+}
+
+pub enum CopyAsciiResult<T, U> {
+ Stop(T),
+ GoOn(U),
+}
+
+pub enum NonAscii {
+ BmpExclAscii(u16),
+ Astral(char),
+}
+
+pub enum Unicode {
+ Ascii(u8),
+ NonAscii(NonAscii),
+}
+
+// Start UTF-16LE/BE fast path
+
+pub trait Endian {
+ const OPPOSITE_ENDIAN: bool;
+}
+
+pub struct BigEndian;
+
+impl Endian for BigEndian {
+ #[cfg(target_endian = "little")]
+ const OPPOSITE_ENDIAN: bool = true;
+
+ #[cfg(target_endian = "big")]
+ const OPPOSITE_ENDIAN: bool = false;
+}
+
+pub struct LittleEndian;
+
+impl Endian for LittleEndian {
+ #[cfg(target_endian = "little")]
+ const OPPOSITE_ENDIAN: bool = false;
+
+ #[cfg(target_endian = "big")]
+ const OPPOSITE_ENDIAN: bool = true;
+}
+
+#[derive(Debug, Copy, Clone)]
+struct UnalignedU16Slice {
+ ptr: *const u8,
+ len: usize,
+}
+
+impl UnalignedU16Slice {
+ #[inline(always)]
+ pub unsafe fn new(ptr: *const u8, len: usize) -> UnalignedU16Slice {
+ UnalignedU16Slice { ptr, len }
+ }
+
+ #[inline(always)]
+ pub fn trim_last(&mut self) {
+ assert!(self.len > 0);
+ self.len -= 1;
+ }
+
+ #[inline(always)]
+ pub fn at(&self, i: usize) -> u16 {
+ use core::mem::MaybeUninit;
+
+ assert!(i < self.len);
+ unsafe {
+ let mut u: MaybeUninit<u16> = MaybeUninit::uninit();
+ ::core::ptr::copy_nonoverlapping(self.ptr.add(i * 2), u.as_mut_ptr() as *mut u8, 2);
+ u.assume_init()
+ }
+ }
+
+ #[cfg(feature = "simd-accel")]
+ #[inline(always)]
+ pub fn simd_at(&self, i: usize) -> u16x8 {
+ assert!(i + SIMD_STRIDE_SIZE / 2 <= self.len);
+ let byte_index = i * 2;
+ unsafe { to_u16_lanes(load16_unaligned(self.ptr.add(byte_index))) }
+ }
+
+ #[inline(always)]
+ pub fn len(&self) -> usize {
+ self.len
+ }
+
+ #[inline(always)]
+ pub fn tail(&self, from: usize) -> UnalignedU16Slice {
+ // XXX the return value should be restricted not to
+ // outlive self.
+ assert!(from <= self.len);
+ unsafe { UnalignedU16Slice::new(self.ptr.add(from * 2), self.len - from) }
+ }
+
+ #[cfg(feature = "simd-accel")]
+ #[inline(always)]
+ pub fn copy_bmp_to<E: Endian>(&self, other: &mut [u16]) -> Option<(u16, usize)> {
+ assert!(self.len <= other.len());
+ let mut offset = 0;
+ if SIMD_STRIDE_SIZE / 2 <= self.len {
+ let len_minus_stride = self.len - SIMD_STRIDE_SIZE / 2;
+ loop {
+ let mut simd = self.simd_at(offset);
+ if E::OPPOSITE_ENDIAN {
+ simd = simd_byte_swap(simd);
+ }
+ unsafe {
+ store8_unaligned(other.as_mut_ptr().add(offset), simd);
+ }
+ if contains_surrogates(simd) {
+ break;
+ }
+ offset += SIMD_STRIDE_SIZE / 2;
+ if offset > len_minus_stride {
+ break;
+ }
+ }
+ }
+ while offset < self.len {
+ let unit = swap_if_opposite_endian::<E>(self.at(offset));
+ other[offset] = unit;
+ if super::in_range16(unit, 0xD800, 0xE000) {
+ return Some((unit, offset));
+ }
+ offset += 1;
+ }
+ None
+ }
+
+ #[cfg(not(feature = "simd-accel"))]
+ #[inline(always)]
+ fn copy_bmp_to<E: Endian>(&self, other: &mut [u16]) -> Option<(u16, usize)> {
+ assert!(self.len <= other.len());
+ for (i, target) in other.iter_mut().enumerate().take(self.len) {
+ let unit = swap_if_opposite_endian::<E>(self.at(i));
+ *target = unit;
+ if super::in_range16(unit, 0xD800, 0xE000) {
+ return Some((unit, i));
+ }
+ }
+ None
+ }
+}
+
+#[inline(always)]
+fn copy_unaligned_basic_latin_to_ascii_alu<E: Endian>(
+ src: UnalignedU16Slice,
+ dst: &mut [u8],
+ offset: usize,
+) -> CopyAsciiResult<usize, (u16, usize)> {
+ let len = ::core::cmp::min(src.len(), dst.len());
+ let mut i = 0usize;
+ loop {
+ if i == len {
+ return CopyAsciiResult::Stop(i + offset);
+ }
+ let unit = swap_if_opposite_endian::<E>(src.at(i));
+ if unit > 0x7F {
+ return CopyAsciiResult::GoOn((unit, i + offset));
+ }
+ dst[i] = unit as u8;
+ i += 1;
+ }
+}
+
+#[inline(always)]
+fn swap_if_opposite_endian<E: Endian>(unit: u16) -> u16 {
+ if E::OPPOSITE_ENDIAN {
+ unit.swap_bytes()
+ } else {
+ unit
+ }
+}
+
+#[cfg(not(feature = "simd-accel"))]
+#[inline(always)]
+fn copy_unaligned_basic_latin_to_ascii<E: Endian>(
+ src: UnalignedU16Slice,
+ dst: &mut [u8],
+) -> CopyAsciiResult<usize, (u16, usize)> {
+ copy_unaligned_basic_latin_to_ascii_alu::<E>(src, dst, 0)
+}
+
+#[cfg(feature = "simd-accel")]
+#[inline(always)]
+fn copy_unaligned_basic_latin_to_ascii<E: Endian>(
+ src: UnalignedU16Slice,
+ dst: &mut [u8],
+) -> CopyAsciiResult<usize, (u16, usize)> {
+ let len = ::core::cmp::min(src.len(), dst.len());
+ let mut offset = 0;
+ if SIMD_STRIDE_SIZE <= len {
+ let len_minus_stride = len - SIMD_STRIDE_SIZE;
+ loop {
+ let mut first = src.simd_at(offset);
+ let mut second = src.simd_at(offset + (SIMD_STRIDE_SIZE / 2));
+ if E::OPPOSITE_ENDIAN {
+ first = simd_byte_swap(first);
+ second = simd_byte_swap(second);
+ }
+ if !simd_is_basic_latin(first | second) {
+ break;
+ }
+ let packed = simd_pack(first, second);
+ unsafe {
+ store16_unaligned(dst.as_mut_ptr().add(offset), packed);
+ }
+ offset += SIMD_STRIDE_SIZE;
+ if offset > len_minus_stride {
+ break;
+ }
+ }
+ }
+ copy_unaligned_basic_latin_to_ascii_alu::<E>(src.tail(offset), &mut dst[offset..], offset)
+}
+
+#[inline(always)]
+fn convert_unaligned_utf16_to_utf8<E: Endian>(
+ src: UnalignedU16Slice,
+ dst: &mut [u8],
+) -> (usize, usize, bool) {
+ if dst.len() < 4 {
+ return (0, 0, false);
+ }
+ let mut src_pos = 0usize;
+ let mut dst_pos = 0usize;
+ let src_len = src.len();
+ let dst_len_minus_three = dst.len() - 3;
+ 'outer: loop {
+ let mut non_ascii = match copy_unaligned_basic_latin_to_ascii::<E>(
+ src.tail(src_pos),
+ &mut dst[dst_pos..],
+ ) {
+ CopyAsciiResult::GoOn((unit, read_written)) => {
+ src_pos += read_written;
+ dst_pos += read_written;
+ unit
+ }
+ CopyAsciiResult::Stop(read_written) => {
+ return (src_pos + read_written, dst_pos + read_written, false);
+ }
+ };
+ if dst_pos >= dst_len_minus_three {
+ break 'outer;
+ }
+ // We have enough destination space to commit to
+ // having read `non_ascii`.
+ src_pos += 1;
+ 'inner: loop {
+ let non_ascii_minus_surrogate_start = non_ascii.wrapping_sub(0xD800);
+ if non_ascii_minus_surrogate_start > (0xDFFF - 0xD800) {
+ if non_ascii < 0x800 {
+ dst[dst_pos] = ((non_ascii >> 6) | 0xC0) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = ((non_ascii & 0x3F) | 0x80) as u8;
+ dst_pos += 1;
+ } else {
+ dst[dst_pos] = ((non_ascii >> 12) | 0xE0) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = (((non_ascii & 0xFC0) >> 6) | 0x80) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = ((non_ascii & 0x3F) | 0x80) as u8;
+ dst_pos += 1;
+ }
+ } else if non_ascii_minus_surrogate_start <= (0xDBFF - 0xD800) {
+ // high surrogate
+ if src_pos < src_len {
+ let second = swap_if_opposite_endian::<E>(src.at(src_pos));
+ let second_minus_low_surrogate_start = second.wrapping_sub(0xDC00);
+ if second_minus_low_surrogate_start <= (0xDFFF - 0xDC00) {
+ // The next code unit is a low surrogate. Advance position.
+ src_pos += 1;
+ let point = (u32::from(non_ascii) << 10) + u32::from(second)
+ - (((0xD800u32 << 10) - 0x10000u32) + 0xDC00u32);
+
+ dst[dst_pos] = ((point >> 18) | 0xF0u32) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = (((point & 0x3F000u32) >> 12) | 0x80u32) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = (((point & 0xFC0u32) >> 6) | 0x80u32) as u8;
+ dst_pos += 1;
+ dst[dst_pos] = ((point & 0x3Fu32) | 0x80u32) as u8;
+ dst_pos += 1;
+ } else {
+ // The next code unit is not a low surrogate. Don't advance
+ // position and treat the high surrogate as unpaired.
+ return (src_pos, dst_pos, true);
+ }
+ } else {
+ // Unpaired surrogate at the end of buffer
+ return (src_pos, dst_pos, true);
+ }
+ } else {
+ // Unpaired low surrogate
+ return (src_pos, dst_pos, true);
+ }
+ if dst_pos >= dst_len_minus_three || src_pos == src_len {
+ break 'outer;
+ }
+ let unit = swap_if_opposite_endian::<E>(src.at(src_pos));
+ src_pos += 1;
+ if unit > 0x7F {
+ non_ascii = unit;
+ continue 'inner;
+ }
+ dst[dst_pos] = unit as u8;
+ dst_pos += 1;
+ continue 'outer;
+ }
+ }
+ (src_pos, dst_pos, false)
+}
+
+// Byte source
+
+pub struct ByteSource<'a> {
+ slice: &'a [u8],
+ pos: usize,
+}
+
+impl<'a> ByteSource<'a> {
+ #[inline(always)]
+ pub fn new(src: &[u8]) -> ByteSource {
+ ByteSource { slice: src, pos: 0 }
+ }
+ #[inline(always)]
+ pub fn check_available<'b>(&'b mut self) -> Space<ByteReadHandle<'b, 'a>> {
+ if self.pos < self.slice.len() {
+ Space::Available(ByteReadHandle::new(self))
+ } else {
+ Space::Full(self.consumed())
+ }
+ }
+ #[inline(always)]
+ fn read(&mut self) -> u8 {
+ let ret = self.slice[self.pos];
+ self.pos += 1;
+ ret
+ }
+ #[inline(always)]
+ fn unread(&mut self) -> usize {
+ self.pos -= 1;
+ self.pos
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.pos
+ }
+}
+
+pub struct ByteReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut ByteSource<'b>,
+}
+
+impl<'a, 'b> ByteReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut ByteSource<'b>) -> ByteReadHandle<'a, 'b> {
+ ByteReadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn read(self) -> (u8, ByteUnreadHandle<'a, 'b>) {
+ let byte = self.source.read();
+ let handle = ByteUnreadHandle::new(self.source);
+ (byte, handle)
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+}
+
+pub struct ByteUnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut ByteSource<'b>,
+}
+
+impl<'a, 'b> ByteUnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut ByteSource<'b>) -> ByteUnreadHandle<'a, 'b> {
+ ByteUnreadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn unread(self) -> usize {
+ self.source.unread()
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut ByteSource<'b> {
+ self.source
+ }
+}
+
+// UTF-16 destination
+
+pub struct Utf16BmpHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut Utf16Destination<'b>,
+}
+
+impl<'a, 'b> Utf16BmpHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut Utf16Destination<'b>) -> Utf16BmpHandle<'a, 'b> {
+ Utf16BmpHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_ascii(self, ascii: u8) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_ascii(ascii);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp_excl_ascii(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_bmp_excl_ascii(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_mid_bmp(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_mid_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_upper_bmp(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_upper_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf16Destination<'b> {
+ self.dest
+ }
+}
+
+pub struct Utf16AstralHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut Utf16Destination<'b>,
+}
+
+impl<'a, 'b> Utf16AstralHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut Utf16Destination<'b>) -> Utf16AstralHandle<'a, 'b> {
+ Utf16AstralHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_ascii(self, ascii: u8) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_ascii(ascii);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp_excl_ascii(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_bmp_excl_ascii(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_upper_bmp(self, bmp: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_upper_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_astral(self, astral: u32) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_astral(astral);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_surrogate_pair(self, high: u16, low: u16) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_surrogate_pair(high, low);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_big5_combination(
+ self,
+ combined: u16,
+ combining: u16,
+ ) -> &'a mut Utf16Destination<'b> {
+ self.dest.write_big5_combination(combined, combining);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf16Destination<'b> {
+ self.dest
+ }
+}
+
+pub struct Utf16Destination<'a> {
+ slice: &'a mut [u16],
+ pos: usize,
+}
+
+impl<'a> Utf16Destination<'a> {
+ #[inline(always)]
+ pub fn new(dst: &mut [u16]) -> Utf16Destination {
+ Utf16Destination { slice: dst, pos: 0 }
+ }
+ #[inline(always)]
+ pub fn check_space_bmp<'b>(&'b mut self) -> Space<Utf16BmpHandle<'b, 'a>> {
+ if self.pos < self.slice.len() {
+ Space::Available(Utf16BmpHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn check_space_astral<'b>(&'b mut self) -> Space<Utf16AstralHandle<'b, 'a>> {
+ if self.pos + 1 < self.slice.len() {
+ Space::Available(Utf16AstralHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.pos
+ }
+ #[inline(always)]
+ fn write_code_unit(&mut self, u: u16) {
+ unsafe {
+ // OK, because we checked before handing out a handle.
+ *(self.slice.get_unchecked_mut(self.pos)) = u;
+ }
+ self.pos += 1;
+ }
+ #[inline(always)]
+ fn write_ascii(&mut self, ascii: u8) {
+ debug_assert!(ascii < 0x80);
+ self.write_code_unit(u16::from(ascii));
+ }
+ #[inline(always)]
+ fn write_bmp(&mut self, bmp: u16) {
+ self.write_code_unit(bmp);
+ }
+ #[inline(always)]
+ fn write_bmp_excl_ascii(&mut self, bmp: u16) {
+ debug_assert!(bmp >= 0x80);
+ self.write_code_unit(bmp);
+ }
+ #[inline(always)]
+ fn write_mid_bmp(&mut self, bmp: u16) {
+ debug_assert!(bmp >= 0x80); // XXX
+ self.write_code_unit(bmp);
+ }
+ #[inline(always)]
+ fn write_upper_bmp(&mut self, bmp: u16) {
+ debug_assert!(bmp >= 0x80);
+ self.write_code_unit(bmp);
+ }
+ #[inline(always)]
+ fn write_astral(&mut self, astral: u32) {
+ debug_assert!(astral > 0xFFFF);
+ debug_assert!(astral <= 0x10_FFFF);
+ self.write_code_unit((0xD7C0 + (astral >> 10)) as u16);
+ self.write_code_unit((0xDC00 + (astral & 0x3FF)) as u16);
+ }
+ #[inline(always)]
+ pub fn write_surrogate_pair(&mut self, high: u16, low: u16) {
+ self.write_code_unit(high);
+ self.write_code_unit(low);
+ }
+ #[inline(always)]
+ fn write_big5_combination(&mut self, combined: u16, combining: u16) {
+ self.write_bmp_excl_ascii(combined);
+ self.write_bmp_excl_ascii(combining);
+ }
+ #[inline(always)]
+ pub fn copy_ascii_from_check_space_bmp<'b>(
+ &'b mut self,
+ source: &mut ByteSource,
+ ) -> CopyAsciiResult<(DecoderResult, usize, usize), (u8, Utf16BmpHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (DecoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (DecoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_basic_latin(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ source.pos += length;
+ self.pos += length;
+ return CopyAsciiResult::Stop((pending, source.pos, self.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ source.pos += consumed;
+ self.pos += consumed;
+ source.pos += 1; // +1 for non_ascii
+ non_ascii
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, Utf16BmpHandle::new(self)))
+ }
+ #[inline(always)]
+ pub fn copy_ascii_from_check_space_astral<'b>(
+ &'b mut self,
+ source: &mut ByteSource,
+ ) -> CopyAsciiResult<(DecoderResult, usize, usize), (u8, Utf16AstralHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = self.slice.len();
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (DecoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (DecoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_basic_latin(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ source.pos += length;
+ self.pos += length;
+ return CopyAsciiResult::Stop((pending, source.pos, self.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ source.pos += consumed;
+ self.pos += consumed;
+ if self.pos + 1 < dst_len {
+ source.pos += 1; // +1 for non_ascii
+ non_ascii
+ } else {
+ return CopyAsciiResult::Stop((
+ DecoderResult::OutputFull,
+ source.pos,
+ self.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, Utf16AstralHandle::new(self)))
+ }
+ #[inline(always)]
+ pub fn copy_utf8_up_to_invalid_from(&mut self, source: &mut ByteSource) {
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let (read, written) = convert_utf8_to_utf16_up_to_invalid(src_remaining, dst_remaining);
+ source.pos += read;
+ self.pos += written;
+ }
+ #[inline(always)]
+ pub fn copy_utf16_from<E: Endian>(
+ &mut self,
+ source: &mut ByteSource,
+ ) -> Option<(usize, usize)> {
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+
+ let mut src_unaligned = unsafe {
+ UnalignedU16Slice::new(
+ src_remaining.as_ptr(),
+ ::core::cmp::min(src_remaining.len() / 2, dst_remaining.len()),
+ )
+ };
+ if src_unaligned.len() == 0 {
+ return None;
+ }
+ let last_unit = swap_if_opposite_endian::<E>(src_unaligned.at(src_unaligned.len() - 1));
+ if super::in_range16(last_unit, 0xD800, 0xDC00) {
+ // Last code unit is a high surrogate. It might
+ // legitimately form a pair later, so let's not
+ // include it.
+ src_unaligned.trim_last();
+ }
+ let mut offset = 0usize;
+ loop {
+ if let Some((surrogate, bmp_len)) = {
+ let src_left = src_unaligned.tail(offset);
+ let dst_left = &mut dst_remaining[offset..src_unaligned.len()];
+ src_left.copy_bmp_to::<E>(dst_left)
+ } {
+ offset += bmp_len; // surrogate has not been consumed yet
+ let second_pos = offset + 1;
+ if surrogate > 0xDBFF || second_pos == src_unaligned.len() {
+ // Unpaired surrogate
+ source.pos += second_pos * 2;
+ self.pos += offset;
+ return Some((source.pos, self.pos));
+ }
+ let second = swap_if_opposite_endian::<E>(src_unaligned.at(second_pos));
+ if !super::in_range16(second, 0xDC00, 0xE000) {
+ // Unpaired surrogate
+ source.pos += second_pos * 2;
+ self.pos += offset;
+ return Some((source.pos, self.pos));
+ }
+ // `surrogate` was already speculatively written
+ dst_remaining[second_pos] = second;
+ offset += 2;
+ continue;
+ } else {
+ source.pos += src_unaligned.len() * 2;
+ self.pos += src_unaligned.len();
+ return None;
+ }
+ }
+ }
+}
+
+// UTF-8 destination
+
+pub struct Utf8BmpHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut Utf8Destination<'b>,
+}
+
+impl<'a, 'b> Utf8BmpHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut Utf8Destination<'b>) -> Utf8BmpHandle<'a, 'b> {
+ Utf8BmpHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_ascii(self, ascii: u8) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_ascii(ascii);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp_excl_ascii(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_bmp_excl_ascii(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_mid_bmp(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_mid_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_upper_bmp(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_upper_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf8Destination<'b> {
+ self.dest
+ }
+}
+
+pub struct Utf8AstralHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut Utf8Destination<'b>,
+}
+
+impl<'a, 'b> Utf8AstralHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut Utf8Destination<'b>) -> Utf8AstralHandle<'a, 'b> {
+ Utf8AstralHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_ascii(self, ascii: u8) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_ascii(ascii);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_bmp_excl_ascii(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_bmp_excl_ascii(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_upper_bmp(self, bmp: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_upper_bmp(bmp);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_astral(self, astral: u32) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_astral(astral);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_surrogate_pair(self, high: u16, low: u16) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_surrogate_pair(high, low);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_big5_combination(
+ self,
+ combined: u16,
+ combining: u16,
+ ) -> &'a mut Utf8Destination<'b> {
+ self.dest.write_big5_combination(combined, combining);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf8Destination<'b> {
+ self.dest
+ }
+}
+
+pub struct Utf8Destination<'a> {
+ slice: &'a mut [u8],
+ pos: usize,
+}
+
+impl<'a> Utf8Destination<'a> {
+ #[inline(always)]
+ pub fn new(dst: &mut [u8]) -> Utf8Destination {
+ Utf8Destination { slice: dst, pos: 0 }
+ }
+ #[inline(always)]
+ pub fn check_space_bmp<'b>(&'b mut self) -> Space<Utf8BmpHandle<'b, 'a>> {
+ if self.pos + 2 < self.slice.len() {
+ Space::Available(Utf8BmpHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn check_space_astral<'b>(&'b mut self) -> Space<Utf8AstralHandle<'b, 'a>> {
+ if self.pos + 3 < self.slice.len() {
+ Space::Available(Utf8AstralHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.pos
+ }
+ #[inline(always)]
+ fn write_code_unit(&mut self, u: u8) {
+ unsafe {
+ // OK, because we checked before handing out a handle.
+ *(self.slice.get_unchecked_mut(self.pos)) = u;
+ }
+ self.pos += 1;
+ }
+ #[inline(always)]
+ fn write_ascii(&mut self, ascii: u8) {
+ debug_assert!(ascii < 0x80);
+ self.write_code_unit(ascii);
+ }
+ #[inline(always)]
+ fn write_bmp(&mut self, bmp: u16) {
+ if bmp < 0x80u16 {
+ self.write_ascii(bmp as u8);
+ } else if bmp < 0x800u16 {
+ self.write_mid_bmp(bmp);
+ } else {
+ self.write_upper_bmp(bmp);
+ }
+ }
+ #[inline(always)]
+ fn write_mid_bmp(&mut self, mid_bmp: u16) {
+ debug_assert!(mid_bmp >= 0x80);
+ debug_assert!(mid_bmp < 0x800);
+ self.write_code_unit(((mid_bmp >> 6) | 0xC0) as u8);
+ self.write_code_unit(((mid_bmp & 0x3F) | 0x80) as u8);
+ }
+ #[inline(always)]
+ fn write_upper_bmp(&mut self, upper_bmp: u16) {
+ debug_assert!(upper_bmp >= 0x800);
+ self.write_code_unit(((upper_bmp >> 12) | 0xE0) as u8);
+ self.write_code_unit((((upper_bmp & 0xFC0) >> 6) | 0x80) as u8);
+ self.write_code_unit(((upper_bmp & 0x3F) | 0x80) as u8);
+ }
+ #[inline(always)]
+ fn write_bmp_excl_ascii(&mut self, bmp: u16) {
+ if bmp < 0x800u16 {
+ self.write_mid_bmp(bmp);
+ } else {
+ self.write_upper_bmp(bmp);
+ }
+ }
+ #[inline(always)]
+ fn write_astral(&mut self, astral: u32) {
+ debug_assert!(astral > 0xFFFF);
+ debug_assert!(astral <= 0x10_FFFF);
+ self.write_code_unit(((astral >> 18) | 0xF0) as u8);
+ self.write_code_unit((((astral & 0x3F000) >> 12) | 0x80) as u8);
+ self.write_code_unit((((astral & 0xFC0) >> 6) | 0x80) as u8);
+ self.write_code_unit(((astral & 0x3F) | 0x80) as u8);
+ }
+ #[inline(always)]
+ pub fn write_surrogate_pair(&mut self, high: u16, low: u16) {
+ self.write_astral(
+ (u32::from(high) << 10) + u32::from(low)
+ - (((0xD800u32 << 10) - 0x10000u32) + 0xDC00u32),
+ );
+ }
+ #[inline(always)]
+ fn write_big5_combination(&mut self, combined: u16, combining: u16) {
+ self.write_mid_bmp(combined);
+ self.write_mid_bmp(combining);
+ }
+ #[inline(always)]
+ pub fn copy_ascii_from_check_space_bmp<'b>(
+ &'b mut self,
+ source: &mut ByteSource,
+ ) -> CopyAsciiResult<(DecoderResult, usize, usize), (u8, Utf8BmpHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = self.slice.len();
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (DecoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (DecoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ source.pos += length;
+ self.pos += length;
+ return CopyAsciiResult::Stop((pending, source.pos, self.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ source.pos += consumed;
+ self.pos += consumed;
+ if self.pos + 2 < dst_len {
+ source.pos += 1; // +1 for non_ascii
+ non_ascii
+ } else {
+ return CopyAsciiResult::Stop((
+ DecoderResult::OutputFull,
+ source.pos,
+ self.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, Utf8BmpHandle::new(self)))
+ }
+ #[inline(always)]
+ pub fn copy_ascii_from_check_space_astral<'b>(
+ &'b mut self,
+ source: &mut ByteSource,
+ ) -> CopyAsciiResult<(DecoderResult, usize, usize), (u8, Utf8AstralHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = self.slice.len();
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (DecoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (DecoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ source.pos += length;
+ self.pos += length;
+ return CopyAsciiResult::Stop((pending, source.pos, self.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ source.pos += consumed;
+ self.pos += consumed;
+ if self.pos + 3 < dst_len {
+ source.pos += 1; // +1 for non_ascii
+ non_ascii
+ } else {
+ return CopyAsciiResult::Stop((
+ DecoderResult::OutputFull,
+ source.pos,
+ self.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, Utf8AstralHandle::new(self)))
+ }
+ #[inline(always)]
+ pub fn copy_utf8_up_to_invalid_from(&mut self, source: &mut ByteSource) {
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+ let min_len = ::core::cmp::min(src_remaining.len(), dst_remaining.len());
+ // Validate first, then memcpy to let memcpy do its thing even for
+ // non-ASCII. (And potentially do something better than SSE2 for ASCII.)
+ let valid_len = utf8_valid_up_to(&src_remaining[..min_len]);
+ (&mut dst_remaining[..valid_len]).copy_from_slice(&src_remaining[..valid_len]);
+ source.pos += valid_len;
+ self.pos += valid_len;
+ }
+ #[inline(always)]
+ pub fn copy_utf16_from<E: Endian>(
+ &mut self,
+ source: &mut ByteSource,
+ ) -> Option<(usize, usize)> {
+ let src_remaining = &source.slice[source.pos..];
+ let dst_remaining = &mut self.slice[self.pos..];
+
+ let mut src_unaligned =
+ unsafe { UnalignedU16Slice::new(src_remaining.as_ptr(), src_remaining.len() / 2) };
+ if src_unaligned.len() == 0 {
+ return None;
+ }
+ let mut last_unit = src_unaligned.at(src_unaligned.len() - 1);
+ if E::OPPOSITE_ENDIAN {
+ last_unit = last_unit.swap_bytes();
+ }
+ if super::in_range16(last_unit, 0xD800, 0xDC00) {
+ // Last code unit is a high surrogate. It might
+ // legitimately form a pair later, so let's not
+ // include it.
+ src_unaligned.trim_last();
+ }
+ let (read, written, had_error) =
+ convert_unaligned_utf16_to_utf8::<E>(src_unaligned, dst_remaining);
+ source.pos += read * 2;
+ self.pos += written;
+ if had_error {
+ Some((source.pos, self.pos))
+ } else {
+ None
+ }
+ }
+}
+
+// UTF-16 source
+
+pub struct Utf16Source<'a> {
+ slice: &'a [u16],
+ pos: usize,
+ old_pos: usize,
+}
+
+impl<'a> Utf16Source<'a> {
+ #[inline(always)]
+ pub fn new(src: &[u16]) -> Utf16Source {
+ Utf16Source {
+ slice: src,
+ pos: 0,
+ old_pos: 0,
+ }
+ }
+ #[inline(always)]
+ pub fn check_available<'b>(&'b mut self) -> Space<Utf16ReadHandle<'b, 'a>> {
+ if self.pos < self.slice.len() {
+ Space::Available(Utf16ReadHandle::new(self))
+ } else {
+ Space::Full(self.consumed())
+ }
+ }
+ #[cfg_attr(feature = "cargo-clippy", allow(collapsible_if))]
+ #[inline(always)]
+ fn read(&mut self) -> char {
+ self.old_pos = self.pos;
+ let unit = self.slice[self.pos];
+ self.pos += 1;
+ let unit_minus_surrogate_start = unit.wrapping_sub(0xD800);
+ if unit_minus_surrogate_start > (0xDFFF - 0xD800) {
+ return unsafe { ::core::char::from_u32_unchecked(u32::from(unit)) };
+ }
+ if unit_minus_surrogate_start <= (0xDBFF - 0xD800) {
+ // high surrogate
+ if self.pos < self.slice.len() {
+ let second = self.slice[self.pos];
+ let second_minus_low_surrogate_start = second.wrapping_sub(0xDC00);
+ if second_minus_low_surrogate_start <= (0xDFFF - 0xDC00) {
+ // The next code unit is a low surrogate. Advance position.
+ self.pos += 1;
+ return unsafe {
+ ::core::char::from_u32_unchecked(
+ (u32::from(unit) << 10) + u32::from(second)
+ - (((0xD800u32 << 10) - 0x10000u32) + 0xDC00u32),
+ )
+ };
+ }
+ // The next code unit is not a low surrogate. Don't advance
+ // position and treat the high surrogate as unpaired.
+ // fall through
+ }
+ // Unpaired surrogate at the end of buffer, fall through
+ }
+ // Unpaired low surrogate
+ '\u{FFFD}'
+ }
+ #[cfg_attr(feature = "cargo-clippy", allow(collapsible_if))]
+ #[inline(always)]
+ fn read_enum(&mut self) -> Unicode {
+ self.old_pos = self.pos;
+ let unit = self.slice[self.pos];
+ self.pos += 1;
+ if unit < 0x80 {
+ return Unicode::Ascii(unit as u8);
+ }
+ let unit_minus_surrogate_start = unit.wrapping_sub(0xD800);
+ if unit_minus_surrogate_start > (0xDFFF - 0xD800) {
+ return Unicode::NonAscii(NonAscii::BmpExclAscii(unit));
+ }
+ if unit_minus_surrogate_start <= (0xDBFF - 0xD800) {
+ // high surrogate
+ if self.pos < self.slice.len() {
+ let second = self.slice[self.pos];
+ let second_minus_low_surrogate_start = second.wrapping_sub(0xDC00);
+ if second_minus_low_surrogate_start <= (0xDFFF - 0xDC00) {
+ // The next code unit is a low surrogate. Advance position.
+ self.pos += 1;
+ return Unicode::NonAscii(NonAscii::Astral(unsafe {
+ ::core::char::from_u32_unchecked(
+ (u32::from(unit) << 10) + u32::from(second)
+ - (((0xD800u32 << 10) - 0x10000u32) + 0xDC00u32),
+ )
+ }));
+ }
+ // The next code unit is not a low surrogate. Don't advance
+ // position and treat the high surrogate as unpaired.
+ // fall through
+ }
+ // Unpaired surrogate at the end of buffer, fall through
+ }
+ // Unpaired low surrogate
+ Unicode::NonAscii(NonAscii::BmpExclAscii(0xFFFDu16))
+ }
+ #[inline(always)]
+ fn unread(&mut self) -> usize {
+ self.pos = self.old_pos;
+ self.pos
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.pos
+ }
+ #[inline(always)]
+ pub fn copy_ascii_to_check_space_two<'b>(
+ &mut self,
+ dest: &'b mut ByteDestination<'a>,
+ ) -> CopyAsciiResult<(EncoderResult, usize, usize), (NonAscii, ByteTwoHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = dest.slice.len();
+ let src_remaining = &self.slice[self.pos..];
+ let dst_remaining = &mut dest.slice[dest.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (EncoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (EncoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ basic_latin_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ self.pos += length;
+ dest.pos += length;
+ return CopyAsciiResult::Stop((pending, self.pos, dest.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ self.pos += consumed;
+ dest.pos += consumed;
+ if dest.pos + 1 < dst_len {
+ self.pos += 1; // commit to reading `non_ascii`
+ let unit = non_ascii;
+ let unit_minus_surrogate_start = unit.wrapping_sub(0xD800);
+ if unit_minus_surrogate_start > (0xDFFF - 0xD800) {
+ NonAscii::BmpExclAscii(unit)
+ } else if unit_minus_surrogate_start <= (0xDBFF - 0xD800) {
+ // high surrogate
+ if self.pos < self.slice.len() {
+ let second = self.slice[self.pos];
+ let second_minus_low_surrogate_start = second.wrapping_sub(0xDC00);
+ if second_minus_low_surrogate_start <= (0xDFFF - 0xDC00) {
+ // The next code unit is a low surrogate. Advance position.
+ self.pos += 1;
+ NonAscii::Astral(unsafe {
+ ::core::char::from_u32_unchecked(
+ (u32::from(unit) << 10) + u32::from(second)
+ - (((0xD800u32 << 10) - 0x10000u32) + 0xDC00u32),
+ )
+ })
+ } else {
+ // The next code unit is not a low surrogate. Don't advance
+ // position and treat the high surrogate as unpaired.
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ }
+ } else {
+ // Unpaired surrogate at the end of the buffer.
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ }
+ } else {
+ // Unpaired low surrogate
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ }
+ } else {
+ return CopyAsciiResult::Stop((
+ EncoderResult::OutputFull,
+ self.pos,
+ dest.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, ByteTwoHandle::new(dest)))
+ }
+ #[inline(always)]
+ pub fn copy_ascii_to_check_space_four<'b>(
+ &mut self,
+ dest: &'b mut ByteDestination<'a>,
+ ) -> CopyAsciiResult<(EncoderResult, usize, usize), (NonAscii, ByteFourHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = dest.slice.len();
+ let src_remaining = &self.slice[self.pos..];
+ let dst_remaining = &mut dest.slice[dest.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (EncoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (EncoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ basic_latin_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ self.pos += length;
+ dest.pos += length;
+ return CopyAsciiResult::Stop((pending, self.pos, dest.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ self.pos += consumed;
+ dest.pos += consumed;
+ if dest.pos + 3 < dst_len {
+ self.pos += 1; // commit to reading `non_ascii`
+ let unit = non_ascii;
+ let unit_minus_surrogate_start = unit.wrapping_sub(0xD800);
+ if unit_minus_surrogate_start > (0xDFFF - 0xD800) {
+ NonAscii::BmpExclAscii(unit)
+ } else if unit_minus_surrogate_start <= (0xDBFF - 0xD800) {
+ // high surrogate
+ if self.pos == self.slice.len() {
+ // Unpaired surrogate at the end of the buffer.
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ } else {
+ let second = self.slice[self.pos];
+ let second_minus_low_surrogate_start = second.wrapping_sub(0xDC00);
+ if second_minus_low_surrogate_start <= (0xDFFF - 0xDC00) {
+ // The next code unit is a low surrogate. Advance position.
+ self.pos += 1;
+ NonAscii::Astral(unsafe {
+ ::core::char::from_u32_unchecked(
+ (u32::from(unit) << 10) + u32::from(second)
+ - (((0xD800u32 << 10) - 0x1_0000u32) + 0xDC00u32),
+ )
+ })
+ } else {
+ // The next code unit is not a low surrogate. Don't advance
+ // position and treat the high surrogate as unpaired.
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ }
+ }
+ } else {
+ // Unpaired low surrogate
+ NonAscii::BmpExclAscii(0xFFFDu16)
+ }
+ } else {
+ return CopyAsciiResult::Stop((
+ EncoderResult::OutputFull,
+ self.pos,
+ dest.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, ByteFourHandle::new(dest)))
+ }
+}
+
+pub struct Utf16ReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut Utf16Source<'b>,
+}
+
+impl<'a, 'b> Utf16ReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut Utf16Source<'b>) -> Utf16ReadHandle<'a, 'b> {
+ Utf16ReadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn read(self) -> (char, Utf16UnreadHandle<'a, 'b>) {
+ let character = self.source.read();
+ let handle = Utf16UnreadHandle::new(self.source);
+ (character, handle)
+ }
+ #[inline(always)]
+ pub fn read_enum(self) -> (Unicode, Utf16UnreadHandle<'a, 'b>) {
+ let character = self.source.read_enum();
+ let handle = Utf16UnreadHandle::new(self.source);
+ (character, handle)
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+}
+
+pub struct Utf16UnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut Utf16Source<'b>,
+}
+
+impl<'a, 'b> Utf16UnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut Utf16Source<'b>) -> Utf16UnreadHandle<'a, 'b> {
+ Utf16UnreadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn unread(self) -> usize {
+ self.source.unread()
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf16Source<'b> {
+ self.source
+ }
+}
+
+// UTF-8 source
+
+pub struct Utf8Source<'a> {
+ slice: &'a [u8],
+ pos: usize,
+ old_pos: usize,
+}
+
+impl<'a> Utf8Source<'a> {
+ #[inline(always)]
+ pub fn new(src: &str) -> Utf8Source {
+ Utf8Source {
+ slice: src.as_bytes(),
+ pos: 0,
+ old_pos: 0,
+ }
+ }
+ #[inline(always)]
+ pub fn check_available<'b>(&'b mut self) -> Space<Utf8ReadHandle<'b, 'a>> {
+ if self.pos < self.slice.len() {
+ Space::Available(Utf8ReadHandle::new(self))
+ } else {
+ Space::Full(self.consumed())
+ }
+ }
+ #[inline(always)]
+ fn read(&mut self) -> char {
+ self.old_pos = self.pos;
+ let unit = self.slice[self.pos];
+ if unit < 0x80 {
+ self.pos += 1;
+ return char::from(unit);
+ }
+ if unit < 0xE0 {
+ let point =
+ ((u32::from(unit) & 0x1F) << 6) | (u32::from(self.slice[self.pos + 1]) & 0x3F);
+ self.pos += 2;
+ return unsafe { ::core::char::from_u32_unchecked(point) };
+ }
+ if unit < 0xF0 {
+ let point = ((u32::from(unit) & 0xF) << 12)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 2]) & 0x3F);
+ self.pos += 3;
+ return unsafe { ::core::char::from_u32_unchecked(point) };
+ }
+ let point = ((u32::from(unit) & 0x7) << 18)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 12)
+ | ((u32::from(self.slice[self.pos + 2]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 3]) & 0x3F);
+ self.pos += 4;
+ unsafe { ::core::char::from_u32_unchecked(point) }
+ }
+ #[inline(always)]
+ fn read_enum(&mut self) -> Unicode {
+ self.old_pos = self.pos;
+ let unit = self.slice[self.pos];
+ if unit < 0x80 {
+ self.pos += 1;
+ return Unicode::Ascii(unit);
+ }
+ if unit < 0xE0 {
+ let point =
+ ((u16::from(unit) & 0x1F) << 6) | (u16::from(self.slice[self.pos + 1]) & 0x3F);
+ self.pos += 2;
+ return Unicode::NonAscii(NonAscii::BmpExclAscii(point));
+ }
+ if unit < 0xF0 {
+ let point = ((u16::from(unit) & 0xF) << 12)
+ | ((u16::from(self.slice[self.pos + 1]) & 0x3F) << 6)
+ | (u16::from(self.slice[self.pos + 2]) & 0x3F);
+ self.pos += 3;
+ return Unicode::NonAscii(NonAscii::BmpExclAscii(point));
+ }
+ let point = ((u32::from(unit) & 0x7) << 18)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 12)
+ | ((u32::from(self.slice[self.pos + 2]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 3]) & 0x3F);
+ self.pos += 4;
+ Unicode::NonAscii(NonAscii::Astral(unsafe {
+ ::core::char::from_u32_unchecked(point)
+ }))
+ }
+ #[inline(always)]
+ fn unread(&mut self) -> usize {
+ self.pos = self.old_pos;
+ self.pos
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.pos
+ }
+ #[inline(always)]
+ pub fn copy_ascii_to_check_space_one<'b>(
+ &mut self,
+ dest: &'b mut ByteDestination<'a>,
+ ) -> CopyAsciiResult<(EncoderResult, usize, usize), (NonAscii, ByteOneHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let src_remaining = &self.slice[self.pos..];
+ let dst_remaining = &mut dest.slice[dest.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (EncoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (EncoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ self.pos += length;
+ dest.pos += length;
+ return CopyAsciiResult::Stop((pending, self.pos, dest.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ self.pos += consumed;
+ dest.pos += consumed;
+ // We don't need to check space in destination, because
+ // `ascii_to_ascii()` already did.
+ if non_ascii < 0xE0 {
+ let point = ((u16::from(non_ascii) & 0x1F) << 6)
+ | (u16::from(self.slice[self.pos + 1]) & 0x3F);
+ self.pos += 2;
+ NonAscii::BmpExclAscii(point)
+ } else if non_ascii < 0xF0 {
+ let point = ((u16::from(non_ascii) & 0xF) << 12)
+ | ((u16::from(self.slice[self.pos + 1]) & 0x3F) << 6)
+ | (u16::from(self.slice[self.pos + 2]) & 0x3F);
+ self.pos += 3;
+ NonAscii::BmpExclAscii(point)
+ } else {
+ let point = ((u32::from(non_ascii) & 0x7) << 18)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 12)
+ | ((u32::from(self.slice[self.pos + 2]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 3]) & 0x3F);
+ self.pos += 4;
+ NonAscii::Astral(unsafe { ::core::char::from_u32_unchecked(point) })
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, ByteOneHandle::new(dest)))
+ }
+ #[inline(always)]
+ pub fn copy_ascii_to_check_space_two<'b>(
+ &mut self,
+ dest: &'b mut ByteDestination<'a>,
+ ) -> CopyAsciiResult<(EncoderResult, usize, usize), (NonAscii, ByteTwoHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = dest.slice.len();
+ let src_remaining = &self.slice[self.pos..];
+ let dst_remaining = &mut dest.slice[dest.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (EncoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (EncoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ self.pos += length;
+ dest.pos += length;
+ return CopyAsciiResult::Stop((pending, self.pos, dest.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ self.pos += consumed;
+ dest.pos += consumed;
+ if dest.pos + 1 < dst_len {
+ if non_ascii < 0xE0 {
+ let point = ((u16::from(non_ascii) & 0x1F) << 6)
+ | (u16::from(self.slice[self.pos + 1]) & 0x3F);
+ self.pos += 2;
+ NonAscii::BmpExclAscii(point)
+ } else if non_ascii < 0xF0 {
+ let point = ((u16::from(non_ascii) & 0xF) << 12)
+ | ((u16::from(self.slice[self.pos + 1]) & 0x3F) << 6)
+ | (u16::from(self.slice[self.pos + 2]) & 0x3F);
+ self.pos += 3;
+ NonAscii::BmpExclAscii(point)
+ } else {
+ let point = ((u32::from(non_ascii) & 0x7) << 18)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 12)
+ | ((u32::from(self.slice[self.pos + 2]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 3]) & 0x3F);
+ self.pos += 4;
+ NonAscii::Astral(unsafe { ::core::char::from_u32_unchecked(point) })
+ }
+ } else {
+ return CopyAsciiResult::Stop((
+ EncoderResult::OutputFull,
+ self.pos,
+ dest.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, ByteTwoHandle::new(dest)))
+ }
+ #[inline(always)]
+ pub fn copy_ascii_to_check_space_four<'b>(
+ &mut self,
+ dest: &'b mut ByteDestination<'a>,
+ ) -> CopyAsciiResult<(EncoderResult, usize, usize), (NonAscii, ByteFourHandle<'b, 'a>)> {
+ let non_ascii_ret = {
+ let dst_len = dest.slice.len();
+ let src_remaining = &self.slice[self.pos..];
+ let dst_remaining = &mut dest.slice[dest.pos..];
+ let (pending, length) = if dst_remaining.len() < src_remaining.len() {
+ (EncoderResult::OutputFull, dst_remaining.len())
+ } else {
+ (EncoderResult::InputEmpty, src_remaining.len())
+ };
+ match unsafe {
+ ascii_to_ascii(src_remaining.as_ptr(), dst_remaining.as_mut_ptr(), length)
+ } {
+ None => {
+ self.pos += length;
+ dest.pos += length;
+ return CopyAsciiResult::Stop((pending, self.pos, dest.pos));
+ }
+ Some((non_ascii, consumed)) => {
+ self.pos += consumed;
+ dest.pos += consumed;
+ if dest.pos + 3 < dst_len {
+ if non_ascii < 0xE0 {
+ let point = ((u16::from(non_ascii) & 0x1F) << 6)
+ | (u16::from(self.slice[self.pos + 1]) & 0x3F);
+ self.pos += 2;
+ NonAscii::BmpExclAscii(point)
+ } else if non_ascii < 0xF0 {
+ let point = ((u16::from(non_ascii) & 0xF) << 12)
+ | ((u16::from(self.slice[self.pos + 1]) & 0x3F) << 6)
+ | (u16::from(self.slice[self.pos + 2]) & 0x3F);
+ self.pos += 3;
+ NonAscii::BmpExclAscii(point)
+ } else {
+ let point = ((u32::from(non_ascii) & 0x7) << 18)
+ | ((u32::from(self.slice[self.pos + 1]) & 0x3F) << 12)
+ | ((u32::from(self.slice[self.pos + 2]) & 0x3F) << 6)
+ | (u32::from(self.slice[self.pos + 3]) & 0x3F);
+ self.pos += 4;
+ NonAscii::Astral(unsafe { ::core::char::from_u32_unchecked(point) })
+ }
+ } else {
+ return CopyAsciiResult::Stop((
+ EncoderResult::OutputFull,
+ self.pos,
+ dest.pos,
+ ));
+ }
+ }
+ }
+ };
+ CopyAsciiResult::GoOn((non_ascii_ret, ByteFourHandle::new(dest)))
+ }
+}
+
+pub struct Utf8ReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut Utf8Source<'b>,
+}
+
+impl<'a, 'b> Utf8ReadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut Utf8Source<'b>) -> Utf8ReadHandle<'a, 'b> {
+ Utf8ReadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn read(self) -> (char, Utf8UnreadHandle<'a, 'b>) {
+ let character = self.source.read();
+ let handle = Utf8UnreadHandle::new(self.source);
+ (character, handle)
+ }
+ #[inline(always)]
+ pub fn read_enum(self) -> (Unicode, Utf8UnreadHandle<'a, 'b>) {
+ let character = self.source.read_enum();
+ let handle = Utf8UnreadHandle::new(self.source);
+ (character, handle)
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+}
+
+pub struct Utf8UnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ source: &'a mut Utf8Source<'b>,
+}
+
+impl<'a, 'b> Utf8UnreadHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(src: &'a mut Utf8Source<'b>) -> Utf8UnreadHandle<'a, 'b> {
+ Utf8UnreadHandle { source: src }
+ }
+ #[inline(always)]
+ pub fn unread(self) -> usize {
+ self.source.unread()
+ }
+ #[inline(always)]
+ pub fn consumed(&self) -> usize {
+ self.source.consumed()
+ }
+ #[inline(always)]
+ pub fn commit(self) -> &'a mut Utf8Source<'b> {
+ self.source
+ }
+}
+
+// Byte destination
+
+pub struct ByteOneHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut ByteDestination<'b>,
+}
+
+impl<'a, 'b> ByteOneHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut ByteDestination<'b>) -> ByteOneHandle<'a, 'b> {
+ ByteOneHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_one(self, first: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_one(first);
+ self.dest
+ }
+}
+
+pub struct ByteTwoHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut ByteDestination<'b>,
+}
+
+impl<'a, 'b> ByteTwoHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut ByteDestination<'b>) -> ByteTwoHandle<'a, 'b> {
+ ByteTwoHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_one(self, first: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_one(first);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_two(self, first: u8, second: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_two(first, second);
+ self.dest
+ }
+}
+
+pub struct ByteThreeHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut ByteDestination<'b>,
+}
+
+impl<'a, 'b> ByteThreeHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut ByteDestination<'b>) -> ByteThreeHandle<'a, 'b> {
+ ByteThreeHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_one(self, first: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_one(first);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_two(self, first: u8, second: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_two(first, second);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_three(self, first: u8, second: u8, third: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_three(first, second, third);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_three_return_written(self, first: u8, second: u8, third: u8) -> usize {
+ self.dest.write_three(first, second, third);
+ self.dest.written()
+ }
+}
+
+pub struct ByteFourHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ dest: &'a mut ByteDestination<'b>,
+}
+
+impl<'a, 'b> ByteFourHandle<'a, 'b>
+where
+ 'b: 'a,
+{
+ #[inline(always)]
+ fn new(dst: &'a mut ByteDestination<'b>) -> ByteFourHandle<'a, 'b> {
+ ByteFourHandle { dest: dst }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.dest.written()
+ }
+ #[inline(always)]
+ pub fn write_one(self, first: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_one(first);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_two(self, first: u8, second: u8) -> &'a mut ByteDestination<'b> {
+ self.dest.write_two(first, second);
+ self.dest
+ }
+ #[inline(always)]
+ pub fn write_four(
+ self,
+ first: u8,
+ second: u8,
+ third: u8,
+ fourth: u8,
+ ) -> &'a mut ByteDestination<'b> {
+ self.dest.write_four(first, second, third, fourth);
+ self.dest
+ }
+}
+
+pub struct ByteDestination<'a> {
+ slice: &'a mut [u8],
+ pos: usize,
+}
+
+impl<'a> ByteDestination<'a> {
+ #[inline(always)]
+ pub fn new(dst: &mut [u8]) -> ByteDestination {
+ ByteDestination { slice: dst, pos: 0 }
+ }
+ #[inline(always)]
+ pub fn check_space_one<'b>(&'b mut self) -> Space<ByteOneHandle<'b, 'a>> {
+ if self.pos < self.slice.len() {
+ Space::Available(ByteOneHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn check_space_two<'b>(&'b mut self) -> Space<ByteTwoHandle<'b, 'a>> {
+ if self.pos + 1 < self.slice.len() {
+ Space::Available(ByteTwoHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn check_space_three<'b>(&'b mut self) -> Space<ByteThreeHandle<'b, 'a>> {
+ if self.pos + 2 < self.slice.len() {
+ Space::Available(ByteThreeHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn check_space_four<'b>(&'b mut self) -> Space<ByteFourHandle<'b, 'a>> {
+ if self.pos + 3 < self.slice.len() {
+ Space::Available(ByteFourHandle::new(self))
+ } else {
+ Space::Full(self.written())
+ }
+ }
+ #[inline(always)]
+ pub fn written(&self) -> usize {
+ self.pos
+ }
+ #[inline(always)]
+ fn write_one(&mut self, first: u8) {
+ self.slice[self.pos] = first;
+ self.pos += 1;
+ }
+ #[inline(always)]
+ fn write_two(&mut self, first: u8, second: u8) {
+ self.slice[self.pos] = first;
+ self.slice[self.pos + 1] = second;
+ self.pos += 2;
+ }
+ #[inline(always)]
+ fn write_three(&mut self, first: u8, second: u8, third: u8) {
+ self.slice[self.pos] = first;
+ self.slice[self.pos + 1] = second;
+ self.slice[self.pos + 2] = third;
+ self.pos += 3;
+ }
+ #[inline(always)]
+ fn write_four(&mut self, first: u8, second: u8, third: u8, fourth: u8) {
+ self.slice[self.pos] = first;
+ self.slice[self.pos + 1] = second;
+ self.slice[self.pos + 2] = third;
+ self.slice[self.pos + 3] = fourth;
+ self.pos += 4;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-27 13:19:12 +0000