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Diffstat (limited to 'third_party/rust/url/src/percent_encoding.rs')
| -rw-r--r-- | third_party/rust/url/src/percent_encoding.rs | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/third_party/rust/url/src/percent_encoding.rs b/third_party/rust/url/src/percent_encoding.rs new file mode 100644 index 000000000..a4fb6177a --- /dev/null +++ b/third_party/rust/url/src/percent_encoding.rs @@ -0,0 +1,344 @@ +// Copyright 2013-2016 The rust-url developers. +// +// 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 encoding; +use std::ascii::AsciiExt; +use std::borrow::Cow; +use std::fmt; +use std::slice; +use std::str; + +/// Represents a set of characters / bytes that should be percent-encoded. +/// +/// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set). +/// +/// Different characters need to be encoded in different parts of an URL. +/// For example, a literal `?` question mark in an URL’s path would indicate +/// the start of the query string. +/// A question mark meant to be part of the path therefore needs to be percent-encoded. +/// In the query string however, a question mark does not have any special meaning +/// and does not need to be percent-encoded. +/// +/// A few sets are defined in this module. +/// Use the [`define_encode_set!`](../macro.define_encode_set!.html) macro to define different ones. +pub trait EncodeSet: Clone { + /// Called with UTF-8 bytes rather than code points. + /// Should return true for all non-ASCII bytes. + fn contains(&self, byte: u8) -> bool; +} + +/// Define a new struct +/// that implements the [`EncodeSet`](percent_encoding/trait.EncodeSet.html) trait, +/// for use in [`percent_decode()`](percent_encoding/fn.percent_encode.html) +/// and related functions. +/// +/// Parameters are characters to include in the set in addition to those of the base set. +/// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set). +/// +/// Example +/// ======= +/// +/// ```rust +/// #[macro_use] extern crate url; +/// use url::percent_encoding::{utf8_percent_encode, SIMPLE_ENCODE_SET}; +/// define_encode_set! { +/// /// This encode set is used in the URL parser for query strings. +/// pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] | {' ', '"', '#', '<', '>'} +/// } +/// # fn main() { +/// assert_eq!(utf8_percent_encode("foo bar", QUERY_ENCODE_SET).collect::<String>(), "foo%20bar"); +/// # } +/// ``` +#[macro_export] +macro_rules! define_encode_set { + ($(#[$attr: meta])* pub $name: ident = [$base_set: expr] | {$($ch: pat),*}) => { + $(#[$attr])* + #[derive(Copy, Clone)] + #[allow(non_camel_case_types)] + pub struct $name; + + impl $crate::percent_encoding::EncodeSet for $name { + #[inline] + fn contains(&self, byte: u8) -> bool { + match byte as char { + $( + $ch => true, + )* + _ => $base_set.contains(byte) + } + } + } + } +} + +/// This encode set is used for the path of cannot-be-a-base URLs. +#[derive(Copy, Clone)] +#[allow(non_camel_case_types)] +pub struct SIMPLE_ENCODE_SET; + +impl EncodeSet for SIMPLE_ENCODE_SET { + #[inline] + fn contains(&self, byte: u8) -> bool { + byte < 0x20 || byte > 0x7E + } +} + +define_encode_set! { + /// This encode set is used in the URL parser for query strings. + pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] | {' ', '"', '#', '<', '>'} +} + +define_encode_set! { + /// This encode set is used for path components. + pub DEFAULT_ENCODE_SET = [QUERY_ENCODE_SET] | {'`', '?', '{', '}'} +} + +define_encode_set! { + /// This encode set is used for on '/'-separated path segment + pub PATH_SEGMENT_ENCODE_SET = [DEFAULT_ENCODE_SET] | {'%', '/'} +} + +define_encode_set! { + /// This encode set is used for username and password. + pub USERINFO_ENCODE_SET = [DEFAULT_ENCODE_SET] | { + '/', ':', ';', '=', '@', '[', '\\', ']', '^', '|' + } +} + +/// Return the percent-encoding of the given bytes. +/// +/// This is unconditional, unlike `percent_encode()` which uses an encode set. +pub fn percent_encode_byte(byte: u8) -> &'static str { + let index = usize::from(byte) * 3; + &"\ + %00%01%02%03%04%05%06%07%08%09%0A%0B%0C%0D%0E%0F\ + %10%11%12%13%14%15%16%17%18%19%1A%1B%1C%1D%1E%1F\ + %20%21%22%23%24%25%26%27%28%29%2A%2B%2C%2D%2E%2F\ + %30%31%32%33%34%35%36%37%38%39%3A%3B%3C%3D%3E%3F\ + %40%41%42%43%44%45%46%47%48%49%4A%4B%4C%4D%4E%4F\ + %50%51%52%53%54%55%56%57%58%59%5A%5B%5C%5D%5E%5F\ + %60%61%62%63%64%65%66%67%68%69%6A%6B%6C%6D%6E%6F\ + %70%71%72%73%74%75%76%77%78%79%7A%7B%7C%7D%7E%7F\ + %80%81%82%83%84%85%86%87%88%89%8A%8B%8C%8D%8E%8F\ + %90%91%92%93%94%95%96%97%98%99%9A%9B%9C%9D%9E%9F\ + %A0%A1%A2%A3%A4%A5%A6%A7%A8%A9%AA%AB%AC%AD%AE%AF\ + %B0%B1%B2%B3%B4%B5%B6%B7%B8%B9%BA%BB%BC%BD%BE%BF\ + %C0%C1%C2%C3%C4%C5%C6%C7%C8%C9%CA%CB%CC%CD%CE%CF\ + %D0%D1%D2%D3%D4%D5%D6%D7%D8%D9%DA%DB%DC%DD%DE%DF\ + %E0%E1%E2%E3%E4%E5%E6%E7%E8%E9%EA%EB%EC%ED%EE%EF\ + %F0%F1%F2%F3%F4%F5%F6%F7%F8%F9%FA%FB%FC%FD%FE%FF\ + "[index..index + 3] +} + +/// Percent-encode the given bytes with the given encode set. +/// +/// The encode set define which bytes (in addition to non-ASCII and controls) +/// need to be percent-encoded. +/// The choice of this set depends on context. +/// For example, `?` needs to be encoded in an URL path but not in a query string. +/// +/// The return value is an iterator of `&str` slices (so it has a `.collect::<String>()` method) +/// that also implements `Display` and `Into<Cow<str>>`. +/// The latter returns `Cow::Borrowed` when none of the bytes in `input` +/// are in the given encode set. +#[inline] +pub fn percent_encode<E: EncodeSet>(input: &[u8], encode_set: E) -> PercentEncode<E> { + PercentEncode { + bytes: input, + encode_set: encode_set, + } +} + +/// Percent-encode the UTF-8 encoding of the given string. +/// +/// See `percent_encode()` for how to use the return value. +#[inline] +pub fn utf8_percent_encode<E: EncodeSet>(input: &str, encode_set: E) -> PercentEncode<E> { + percent_encode(input.as_bytes(), encode_set) +} + +/// The return type of `percent_encode()` and `utf8_percent_encode()`. +#[derive(Clone)] +pub struct PercentEncode<'a, E: EncodeSet> { + bytes: &'a [u8], + encode_set: E, +} + +impl<'a, E: EncodeSet> Iterator for PercentEncode<'a, E> { + type Item = &'a str; + + fn next(&mut self) -> Option<&'a str> { + if let Some((&first_byte, remaining)) = self.bytes.split_first() { + if self.encode_set.contains(first_byte) { + self.bytes = remaining; + Some(percent_encode_byte(first_byte)) + } else { + assert!(first_byte.is_ascii()); + for (i, &byte) in remaining.iter().enumerate() { + if self.encode_set.contains(byte) { + // 1 for first_byte + i for previous iterations of this loop + let (unchanged_slice, remaining) = self.bytes.split_at(1 + i); + self.bytes = remaining; + return Some(unsafe { str::from_utf8_unchecked(unchanged_slice) }) + } else { + assert!(byte.is_ascii()); + } + } + let unchanged_slice = self.bytes; + self.bytes = &[][..]; + Some(unsafe { str::from_utf8_unchecked(unchanged_slice) }) + } + } else { + None + } + } + + fn size_hint(&self) -> (usize, Option<usize>) { + if self.bytes.is_empty() { + (0, Some(0)) + } else { + (1, Some(self.bytes.len())) + } + } +} + +impl<'a, E: EncodeSet> fmt::Display for PercentEncode<'a, E> { + fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + for c in (*self).clone() { + try!(formatter.write_str(c)) + } + Ok(()) + } +} + +impl<'a, E: EncodeSet> From<PercentEncode<'a, E>> for Cow<'a, str> { + fn from(mut iter: PercentEncode<'a, E>) -> Self { + match iter.next() { + None => "".into(), + Some(first) => { + match iter.next() { + None => first.into(), + Some(second) => { + let mut string = first.to_owned(); + string.push_str(second); + string.extend(iter); + string.into() + } + } + } + } + } +} + +/// Percent-decode the given bytes. +/// +/// The return value is an iterator of decoded `u8` bytes +/// that also implements `Into<Cow<u8>>` +/// (which returns `Cow::Borrowed` when `input` contains no percent-encoded sequence) +/// and has `decode_utf8()` and `decode_utf8_lossy()` methods. +#[inline] +pub fn percent_decode<'a>(input: &'a [u8]) -> PercentDecode<'a> { + PercentDecode { + bytes: input.iter() + } +} + +/// The return type of `percent_decode()`. +#[derive(Clone)] +pub struct PercentDecode<'a> { + bytes: slice::Iter<'a, u8>, +} + +fn after_percent_sign(iter: &mut slice::Iter<u8>) -> Option<u8> { + let initial_iter = iter.clone(); + let h = iter.next().and_then(|&b| (b as char).to_digit(16)); + let l = iter.next().and_then(|&b| (b as char).to_digit(16)); + if let (Some(h), Some(l)) = (h, l) { + Some(h as u8 * 0x10 + l as u8) + } else { + *iter = initial_iter; + None + } +} + +impl<'a> Iterator for PercentDecode<'a> { + type Item = u8; + + fn next(&mut self) -> Option<u8> { + self.bytes.next().map(|&byte| { + if byte == b'%' { + after_percent_sign(&mut self.bytes).unwrap_or(byte) + } else { + byte + } + }) + } + + fn size_hint(&self) -> (usize, Option<usize>) { + let bytes = self.bytes.len(); + (bytes / 3, Some(bytes)) + } +} + +impl<'a> From<PercentDecode<'a>> for Cow<'a, [u8]> { + fn from(iter: PercentDecode<'a>) -> Self { + match iter.if_any() { + Some(vec) => Cow::Owned(vec), + None => Cow::Borrowed(iter.bytes.as_slice()), + } + } +} + +impl<'a> PercentDecode<'a> { + /// If the percent-decoding is different from the input, return it as a new bytes vector. + pub fn if_any(&self) -> Option<Vec<u8>> { + let mut bytes_iter = self.bytes.clone(); + while bytes_iter.find(|&&b| b == b'%').is_some() { + if let Some(decoded_byte) = after_percent_sign(&mut bytes_iter) { + let initial_bytes = self.bytes.as_slice(); + let unchanged_bytes_len = initial_bytes.len() - bytes_iter.len() - 3; + let mut decoded = initial_bytes[..unchanged_bytes_len].to_owned(); + decoded.push(decoded_byte); + decoded.extend(PercentDecode { + bytes: bytes_iter + }); + return Some(decoded) + } + } + // Nothing to decode + None + } + + /// Decode the result of percent-decoding as UTF-8. + /// + /// This is return `Err` when the percent-decoded bytes are not well-formed in UTF-8. + pub fn decode_utf8(self) -> Result<Cow<'a, str>, str::Utf8Error> { + match self.clone().into() { + Cow::Borrowed(bytes) => { + match str::from_utf8(bytes) { + Ok(s) => Ok(s.into()), + Err(e) => Err(e), + } + } + Cow::Owned(bytes) => { + match String::from_utf8(bytes) { + Ok(s) => Ok(s.into()), + Err(e) => Err(e.utf8_error()), + } + } + } + } + + /// Decode the result of percent-decoding as UTF-8, lossily. + /// + /// Invalid UTF-8 percent-encoded byte sequences will be replaced � U+FFFD, + /// the replacement character. + pub fn decode_utf8_lossy(self) -> Cow<'a, str> { + encoding::decode_utf8_lossy(self.clone().into()) + } +} |