| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/registry/src/github.com-1ecc6299db9ec823/htmlescape-0.3.1/src/decode.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>decode.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../normalize.css"><link rel="stylesheet" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../ayu.css" disabled><link rel="stylesheet" href="../../dark.css" disabled><link rel="stylesheet" href="../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../storage.js"></script><script defer src="../../source-script.js"></script><script defer src="../../source-files.js"></script><script defer src="../../main.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../htmlescape/index.html"><div class="logo-container"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../htmlescape/index.html"><img class="rust-logo" src="../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span>std::io::{<span class="self">self</span>, Write, BufRead, Cursor}; |
| <span class="kw">use </span>std::char; |
| <span class="kw">use </span><span class="self">self</span>::DecodeState::<span class="kw-2">*</span>; |
| <span class="kw">use </span><span class="self">self</span>::DecodeErrKind::<span class="kw-2">*</span>; |
| <span class="kw">use </span>io_support::{<span class="self">self</span>, write_char, CharsError}; |
| <span class="kw">use </span>entities::<span class="kw-2">*</span>; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub enum </span>DecodeErrKind { |
| <span class="doccomment">/// A non-existent named entity was referenced. |
| /// Example: &thisentitydoesnotexist |
| </span>UnknownEntity, |
| |
| <span class="doccomment">/// A numerical escape sequence (&# or &#x) containing an invalid character. |
| /// Examples: `&#32a`, `&#xfoo` |
| </span>MalformedNumEscape, |
| |
| <span class="doccomment">/// A numerical escape sequence (&# or &#x) resolved to an invalid unicode code point. |
| /// Example: `&#xffffff` |
| </span>InvalidCharacter, |
| |
| <span class="doccomment">/// The input ended prematurely (ie. inside an unterminated named entity sequence). |
| </span>PrematureEnd, |
| |
| <span class="doccomment">/// An IO error occured. |
| </span>IoError(io::Error), |
| |
| <span class="doccomment">/// The supplied Reader produces invalid UTF-8. |
| </span>EncodingError, |
| } |
| |
| <span class="kw">impl </span>PartialEq <span class="kw">for </span>DecodeErrKind { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>DecodeErrKind) -> bool { |
| <span class="kw">match </span>(<span class="self">self</span>, other) { |
| (<span class="kw-2">&</span>UnknownEntity, <span class="kw-2">&</span>UnknownEntity) => <span class="bool-val">true</span>, |
| (<span class="kw-2">&</span>MalformedNumEscape, <span class="kw-2">&</span>MalformedNumEscape) => <span class="bool-val">true</span>, |
| (<span class="kw-2">&</span>InvalidCharacter, <span class="kw-2">&</span>InvalidCharacter) => <span class="bool-val">true</span>, |
| (<span class="kw-2">&</span>PrematureEnd, <span class="kw-2">&</span>PrematureEnd) => <span class="bool-val">true</span>, |
| (<span class="kw-2">&</span>IoError(<span class="kw">_</span>), <span class="kw-2">&</span>IoError(<span class="kw">_</span>)) => <span class="bool-val">true</span>, |
| (<span class="kw-2">&</span>EncodingError, <span class="kw-2">&</span>EncodingError) => <span class="bool-val">true</span>, |
| <span class="kw">_ </span>=> <span class="bool-val">false |
| </span>} |
| } |
| } |
| |
| <span class="kw">impl </span>Eq <span class="kw">for </span>DecodeErrKind {} |
| |
| <span class="doccomment">/// Error from decoding a entity-encoded string. |
| </span><span class="attribute">#[derive(Debug, Eq, PartialEq)] |
| </span><span class="kw">pub struct </span>DecodeErr { |
| <span class="doccomment">/// Number of characters read from the input before encountering an error |
| </span><span class="kw">pub </span>position: usize, |
| <span class="doccomment">/// Type of error |
| </span><span class="kw">pub </span>kind: DecodeErrKind |
| } |
| |
| <span class="attribute">#[derive(PartialEq, Eq)] |
| </span><span class="kw">enum </span>DecodeState { |
| Normal, |
| Entity, |
| Named, |
| Numeric, |
| Hex, |
| Dec |
| } |
| |
| <span class="macro">macro_rules! </span>try_parse( |
| (<span class="macro-nonterminal">$parse</span>:expr, <span class="macro-nonterminal">$pos</span>:expr) => ( |
| <span class="kw">match </span><span class="macro-nonterminal">$parse </span>{ |
| <span class="prelude-val">Err</span>(reason) => <span class="kw">return </span><span class="prelude-val">Err</span>(DecodeErr{ position: <span class="macro-nonterminal">$pos</span>, kind: reason}), |
| <span class="prelude-val">Ok</span>(res) => res |
| } |
| );); |
| |
| <span class="macro">macro_rules! </span>try_dec_io( |
| (<span class="macro-nonterminal">$io</span>:expr, <span class="macro-nonterminal">$pos</span>:expr) => ( |
| <span class="kw">match </span><span class="macro-nonterminal">$io </span>{ |
| <span class="prelude-val">Err</span>(e) => <span class="kw">return </span><span class="prelude-val">Err</span>(DecodeErr{ position: <span class="macro-nonterminal">$pos</span>, kind: IoError(e)}), |
| <span class="prelude-val">Ok</span>(res) => res |
| } |
| );); |
| |
| <span class="doccomment">/// Decodes an entity-encoded string from a reader to a writer. |
| /// |
| /// Similar to `decode_html`, except reading from a reader rather than a string, and |
| /// writing to a writer rather than returning a `String`. |
| /// |
| /// # Arguments |
| /// - `reader` - UTF-8 encoded data is read from here. |
| /// - `writer` - UTF8- decoded data is written to here. |
| /// |
| /// # Errors |
| /// Errors can be caused by IO errors, `reader` producing invalid UTF-8, or by syntax errors. |
| </span><span class="kw">pub fn </span>decode_html_rw<R: BufRead, W: Write>(reader: R, writer: <span class="kw-2">&mut </span>W) -> <span class="prelude-ty">Result</span><(), DecodeErr> { |
| <span class="kw">let </span><span class="kw-2">mut </span>state: DecodeState = Normal; |
| <span class="kw">let </span><span class="kw-2">mut </span>pos = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>good_pos = <span class="number">0</span>; |
| <span class="kw">let </span><span class="kw-2">mut </span>buf = String::with_capacity(<span class="number">8</span>); |
| <span class="kw">for </span>c <span class="kw">in </span>io_support::chars(reader) { |
| <span class="kw">let </span>c = <span class="kw">match </span>c { |
| <span class="prelude-val">Err</span>(e) => { |
| <span class="kw">let </span>kind = <span class="kw">match </span>e { |
| CharsError::NotUtf8 => EncodingError, |
| CharsError::Other(io) => IoError(io) |
| }; |
| <span class="kw">return </span><span class="prelude-val">Err</span>(DecodeErr{ position: pos, kind: kind }); |
| } |
| <span class="prelude-val">Ok</span>(c) => c |
| }; |
| <span class="kw">match </span>state { |
| Normal <span class="kw">if </span>c == <span class="string">'&' </span>=> state = Entity, |
| Normal => <span class="macro">try_dec_io!</span>(write_char(writer, c), good_pos), |
| Entity <span class="kw">if </span>c == <span class="string">'#' </span>=> state = Numeric, |
| Entity <span class="kw">if </span>c == <span class="string">';' </span>=> <span class="kw">return </span><span class="prelude-val">Err</span>(DecodeErr{ position: good_pos, kind: UnknownEntity }), |
| Entity => { |
| state = Named; |
| buf.push(c); |
| } |
| Named <span class="kw">if </span>c == <span class="string">';' </span>=> { |
| state = Normal; |
| <span class="kw">let </span>ch = <span class="macro">try_parse!</span>(decode_named_entity(<span class="kw-2">&</span>buf), good_pos); |
| <span class="macro">try_dec_io!</span>(write_char(writer, ch), good_pos); |
| buf.clear(); |
| } |
| Named => buf.push(c), |
| Numeric <span class="kw">if </span>is_digit(c) => { |
| state = Dec; |
| buf.push(c); |
| } |
| Numeric <span class="kw">if </span>c == <span class="string">'x' </span>=> state = Hex, |
| Dec <span class="kw">if </span>c == <span class="string">';' </span>=> { |
| state = Normal; |
| <span class="kw">let </span>ch = <span class="macro">try_parse!</span>(decode_numeric(<span class="kw-2">&</span>buf, <span class="number">10</span>), good_pos); |
| <span class="macro">try_dec_io!</span>(write_char(writer, ch), good_pos); |
| buf.clear(); |
| } |
| Hex <span class="kw">if </span>c == <span class="string">';' </span>=> { |
| state = Normal; |
| <span class="kw">let </span>ch = <span class="macro">try_parse!</span>(decode_numeric(<span class="kw-2">&</span>buf, <span class="number">16</span>), good_pos); |
| <span class="macro">try_dec_io!</span>(write_char(writer, ch), good_pos); |
| buf.clear(); |
| } |
| Hex <span class="kw">if </span>is_hex_digit(c) => buf.push(c), |
| Dec <span class="kw">if </span>is_digit(c) => buf.push(c), |
| Numeric | Hex | Dec => <span class="kw">return </span><span class="prelude-val">Err</span>(DecodeErr{ position: good_pos, kind: MalformedNumEscape}), |
| } |
| pos += <span class="number">1</span>; |
| <span class="kw">if </span>state == Normal { |
| good_pos = pos; |
| } |
| } |
| <span class="kw">if </span>state != Normal { |
| <span class="prelude-val">Err</span>(DecodeErr{ position: good_pos, kind: PrematureEnd}) |
| } <span class="kw">else </span>{ |
| <span class="prelude-val">Ok</span>(()) |
| } |
| } |
| |
| <span class="doccomment">/// Decodes an entity-encoded string. |
| /// |
| /// Decodes an entity encoded string, replacing HTML entities (`&amp;`, `&#20;` ...) with the |
| /// the corresponding character. Case matters for named entities, ie. `&Amp;` is invalid. |
| /// Case does not matter for hex entities, so `&#x2E;` and `&#x2e;` are treated the same. |
| /// |
| /// # Arguments |
| /// - `s` - Entity-encoded string to decode. |
| /// |
| /// # Failure |
| /// The function will fail if input string contains invalid named entities (eg. `&nosuchentity;`), |
| /// invalid hex entities (eg. `&#xRT;`), invalid decimal entities (eg. `&#-1;), unclosed entities |
| /// (`s == "&amp hej och hå"`) or otherwise malformed entities. |
| /// |
| /// This function will never return errors with `kind` set to `IoError` or `EncodingError`. |
| </span><span class="kw">pub fn </span>decode_html(s: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><String, DecodeErr> { |
| <span class="kw">let </span><span class="kw-2">mut </span>writer = Vec::with_capacity(s.len()); |
| <span class="kw">let </span>bytes = s.as_bytes(); |
| <span class="kw">let </span><span class="kw-2">mut </span>reader = Cursor::new(bytes); |
| <span class="kw">let </span>res = decode_html_rw(<span class="kw-2">&mut </span>reader, <span class="kw-2">&mut </span>writer); |
| <span class="kw">match </span>res { |
| <span class="prelude-val">Ok</span>(<span class="kw">_</span>) => <span class="prelude-val">Ok</span>(String::from_utf8(writer).unwrap()), |
| <span class="prelude-val">Err</span>(err) => <span class="prelude-val">Err</span>(err) |
| } |
| } |
| |
| <span class="kw">fn </span>is_digit(c: char) -> bool { c >= <span class="string">'0' </span>&& c <= <span class="string">'9' </span>} |
| |
| <span class="kw">fn </span>is_hex_digit(c: char) -> bool { |
| is_digit(c) || (c >= <span class="string">'a' </span>&& c <= <span class="string">'f'</span>) || (c >= <span class="string">'A' </span>&& c <= <span class="string">'F'</span>) |
| } |
| |
| <span class="kw">fn </span>decode_named_entity(entity: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Result</span><char, DecodeErrKind> { |
| <span class="kw">match </span>NAMED_ENTITIES.binary_search_by(|<span class="kw-2">&</span>(ent, <span class="kw">_</span>)| ent.cmp(entity)) { |
| <span class="prelude-val">Err</span>(..) => <span class="prelude-val">Err</span>(UnknownEntity), |
| <span class="prelude-val">Ok</span>(idx) => { |
| <span class="kw">let </span>(<span class="kw">_</span>, c) = NAMED_ENTITIES[idx]; |
| <span class="prelude-val">Ok</span>(c) |
| } |
| } |
| } |
| |
| <span class="kw">fn </span>decode_numeric(esc: <span class="kw-2">&</span>str, radix: u32) -> <span class="prelude-ty">Result</span><char, DecodeErrKind> { |
| <span class="kw">match </span>u32::from_str_radix(esc, radix) { |
| <span class="prelude-val">Ok</span>(n) => <span class="kw">match </span>char::from_u32(n) { |
| <span class="prelude-val">Some</span>(c) => <span class="prelude-val">Ok</span>(c), |
| <span class="prelude-val">None </span>=> <span class="prelude-val">Err</span>(InvalidCharacter) |
| }, |
| <span class="prelude-val">Err</span>(..) => <span class="prelude-val">Err</span>(MalformedNumEscape) |
| } |
| } |
| |
| </code></pre></div> |
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