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// Copyright 2015-2016 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
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use handles::*;
use variant::*;
use super::*;
pub struct Utf8Decoder {
code_point: u32,
bytes_seen: usize, // 1, 2 or 3: counts continuations only
bytes_needed: usize, // 1, 2 or 3: counts continuations only
lower_boundary: u8,
upper_boundary: u8,
}
impl Utf8Decoder {
pub fn new() -> VariantDecoder {
VariantDecoder::Utf8(Utf8Decoder {
code_point: 0,
bytes_seen: 0,
bytes_needed: 0,
lower_boundary: 0x80u8,
upper_boundary: 0xBFu8,
})
}
pub fn max_utf16_buffer_length(&self, byte_length: usize) -> usize {
byte_length + 1
}
pub fn max_utf8_buffer_length_without_replacement(&self, byte_length: usize) -> usize {
byte_length + 3
}
pub fn max_utf8_buffer_length(&self, byte_length: usize) -> usize {
byte_length * 3 + 3
}
decoder_functions!({},
{
if self.bytes_needed != 0 {
let bad_bytes = (self.bytes_seen + 1) as u8;
self.code_point = 0;
self.bytes_needed = 0;
self.bytes_seen = 0;
return (DecoderResult::Malformed(bad_bytes, 0),
src_consumed,
dest.written());
}
},
{
if self.bytes_needed == 0 {
if b < 0x80u8 {
// XXX optimize ASCII
destination_handle.write_ascii(b);
continue;
}
if b < 0xC2u8 {
return (DecoderResult::Malformed(1, 0),
unread_handle.consumed(),
destination_handle.written());
}
if b < 0xE0u8 {
self.bytes_needed = 1;
self.code_point = b as u32 & 0x1F;
continue;
}
if b < 0xF0u8 {
if b == 0xE0u8 {
self.lower_boundary = 0xA0u8;
} else if b == 0xEDu8 {
self.upper_boundary = 0x9Fu8;
}
self.bytes_needed = 2;
self.code_point = b as u32 & 0xF;
continue;
}
if b < 0xF5u8 {
if b == 0xF0u8 {
self.lower_boundary = 0x90u8;
} else if b == 0xF4u8 {
self.upper_boundary = 0x8Fu8;
}
self.bytes_needed = 3;
self.code_point = b as u32 & 0x7;
continue;
}
return (DecoderResult::Malformed(1, 0),
unread_handle.consumed(),
destination_handle.written());
}
// self.bytes_needed != 0
if !(b >= self.lower_boundary && b <= self.upper_boundary) {
let bad_bytes = (self.bytes_seen + 1) as u8;
self.code_point = 0;
self.bytes_needed = 0;
self.bytes_seen = 0;
self.lower_boundary = 0x80u8;
self.upper_boundary = 0xBFu8;
return (DecoderResult::Malformed(bad_bytes, 0),
unread_handle.unread(),
destination_handle.written());
}
self.lower_boundary = 0x80u8;
self.upper_boundary = 0xBFu8;
self.code_point = (self.code_point << 6) | (b as u32 & 0x3F);
self.bytes_seen += 1;
if self.bytes_seen != self.bytes_needed {
continue;
}
if self.bytes_needed == 3 {
destination_handle.write_astral(self.code_point);
} else {
destination_handle.write_bmp_excl_ascii(self.code_point as u16);
}
self.code_point = 0;
self.bytes_needed = 0;
self.bytes_seen = 0;
continue;
},
self,
src_consumed,
dest,
b,
destination_handle,
unread_handle,
check_space_astral);
}
pub struct Utf8Encoder;
impl Utf8Encoder {
pub fn new(encoding: &'static Encoding) -> Encoder {
Encoder::new(encoding, VariantEncoder::Utf8(Utf8Encoder))
}
pub fn max_buffer_length_from_utf16_without_replacement(&self, u16_length: usize) -> usize {
3 * u16_length
}
pub fn max_buffer_length_from_utf8_without_replacement(&self, byte_length: usize) -> usize {
byte_length
}
pub fn encode_from_utf16_raw(&mut self,
src: &[u16],
dst: &mut [u8],
_last: bool)
-> (EncoderResult, usize, usize) {
let mut source = Utf16Source::new(src);
let mut dest = Utf8Destination::new(dst);
loop {
match source.check_available() {
Space::Full(src_consumed) => {
return (EncoderResult::InputEmpty, src_consumed, dest.written());
}
Space::Available(source_handle) => {
match dest.check_space_astral() {
Space::Full(dst_written) => {
return (EncoderResult::OutputFull,
source_handle.consumed(),
dst_written);
}
Space::Available(destination_handle) => {
let (c, _) = source_handle.read();
// Start non-boilerplate
destination_handle.write_char(c);
// End non-boilerplate
}
}
}
}
}
}
pub fn encode_from_utf8_raw(&mut self,
src: &str,
dst: &mut [u8],
_last: bool)
-> (EncoderResult, usize, usize) {
let mut to_write = src.len();
if to_write <= dst.len() {
unsafe {
::std::ptr::copy_nonoverlapping(src.as_ptr(), dst.as_mut_ptr(), to_write);
}
return (EncoderResult::InputEmpty, to_write, to_write);
}
to_write = dst.len();
// Move back until we find a UTF-8 sequence boundary.
let bytes = src.as_bytes();
while (bytes[to_write] & 0xC0) == 0x80 {
to_write -= 1;
}
unsafe {
::std::ptr::copy_nonoverlapping(src.as_ptr(), dst.as_mut_ptr(), to_write);
}
return (EncoderResult::OutputFull, to_write, to_write);
}
}
#[cfg(test)]
mod tests {
use super::super::testing::*;
use super::super::*;
// fn decode_utf8_to_utf16(bytes: &[u8], expect: &[u16]) {
// decode_to_utf16_without_replacement(UTF_8, bytes, expect);
// }
fn decode_utf8_to_utf8(bytes: &[u8], expect: &str) {
decode_to_utf8_without_replacement(UTF_8, bytes, expect);
}
fn decode_valid_utf8(string: &str) {
decode_utf8_to_utf8(string.as_bytes(), string);
}
// fn encode_utf8_from_utf16(string: &[u16], expect: &[u8]) {
// encode_from_utf16_without_replacement(UTF_8, string, expect);
// }
//
// fn encode_utf8_from_utf8(string: &str, expect: &[u8]) {
// encode_from_utf8_without_replacement(UTF_8, string, expect);
// }
#[test]
fn test_utf8_decode() {
decode_valid_utf8("ab");
decode_valid_utf8("a\u{E4}b");
decode_valid_utf8("a\u{2603}b");
decode_valid_utf8("a\u{1F4A9}b");
decode_utf8_to_utf8(b"a\xC3b", "a\u{FFFD}b");
decode_utf8_to_utf8(b"a\xC3", "a\u{FFFD}");
decode_utf8_to_utf8(b"a\xE2\x98b", "a\u{FFFD}b");
decode_utf8_to_utf8(b"a\xE2\x98", "a\u{FFFD}");
decode_utf8_to_utf8(b"a\xF0\x9F\x92b", "a\u{FFFD}b");
decode_utf8_to_utf8(b"a\xF0\x9F\x92", "a\u{FFFD}");
decode_utf8_to_utf8(b"a\x80b", "a\u{FFFD}b");
decode_utf8_to_utf8(b"a\x80", "a\u{FFFD}");
decode_utf8_to_utf8(b"a\xBFb", "a\u{FFFD}b");
decode_utf8_to_utf8(b"a\xBF", "a\u{FFFD}");
decode_utf8_to_utf8(b"a\x80\x80b", "a\u{FFFD}\u{FFFD}b");
decode_utf8_to_utf8(b"a\x80\x80", "a\u{FFFD}\u{FFFD}");
decode_utf8_to_utf8(b"a\xBF\xBFb", "a\u{FFFD}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xBF\xBF", "a\u{FFFD}\u{FFFD}");
decode_utf8_to_utf8(b"a\xC3\xA4\x80b", "a\u{E4}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xC3\xA4\x80", "a\u{E4}\u{FFFD}");
decode_utf8_to_utf8(b"a\xC3\xA4\xBFb", "a\u{E4}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xC3\xA4\xBF", "a\u{E4}\u{FFFD}");
decode_utf8_to_utf8(b"a\xE2\x98\x83\x80b", "a\u{2603}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xE2\x98\x83\x80", "a\u{2603}\u{FFFD}");
decode_utf8_to_utf8(b"a\xE2\x98\x83\xBFb", "a\u{2603}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xE2\x98\x83\xBF", "a\u{2603}\u{FFFD}");
decode_utf8_to_utf8(b"a\xF0\x9F\x92\xA9\x80b", "a\u{1F4A9}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xF0\x9F\x92\xA9\x80", "a\u{1F4A9}\u{FFFD}");
decode_utf8_to_utf8(b"a\xF0\x9F\x92\xA9\xBFb", "a\u{1F4A9}\u{FFFD}b");
decode_utf8_to_utf8(b"a\xF0\x9F\x92\xA9\xBF", "a\u{1F4A9}\u{FFFD}");
}
}