<!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 `/home/sangenya/.cargo/registry/src/github.com-1ecc6299db9ec823/jpeg-decoder-0.1.22/src/error.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>error.rs - source</title><link rel="stylesheet" type="text/css" href="../../normalize.css"><link rel="stylesheet" type="text/css" href="../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" type="text/css" href="../../light.css" id="themeStyle"><link rel="stylesheet" type="text/css" href="../../dark.css" disabled ><link rel="stylesheet" type="text/css" href="../../ayu.css" disabled ><script id="default-settings"></script><script src="../../storage.js"></script><script src="../../crates.js"></script><noscript><link rel="stylesheet" href="../../noscript.css"></noscript><link rel="icon" type="image/svg+xml" href="../../favicon.svg">
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<span class="kw">use</span> <span class="ident">std::error::Error</span> <span class="kw">as</span> <span class="ident">StdError</span>;
<span class="kw">use</span> <span class="ident">std::fmt</span>;
<span class="kw">use</span> <span class="ident">std::io::Error</span> <span class="kw">as</span> <span class="ident">IoError</span>;
<span class="kw">pub</span> <span class="kw">type</span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">T</span><span class="op">></span> <span class="op">=</span> <span class="ident">::std::result::Result</span><span class="op"><</span><span class="ident">T</span>, <span class="ident">Error</span><span class="op">></span>;
<span class="doccomment">/// An enumeration over JPEG features (currently) unsupported by this library.</span>
<span class="doccomment">///</span>
<span class="doccomment">/// Support for features listed here may be included in future versions of this library.</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">UnsupportedFeature</span> {
<span class="doccomment">/// Hierarchical JPEG.</span>
<span class="ident">Hierarchical</span>,
<span class="doccomment">/// Lossless JPEG.</span>
<span class="ident">Lossless</span>,
<span class="doccomment">/// JPEG using arithmetic entropy coding instead of Huffman coding.</span>
<span class="ident">ArithmeticEntropyCoding</span>,
<span class="doccomment">/// Sample precision in bits. 8 bit sample precision is what is currently supported.</span>
<span class="ident">SamplePrecision</span>(<span class="ident">u8</span>),
<span class="doccomment">/// Number of components in an image. 1, 3 and 4 components are currently supported.</span>
<span class="ident">ComponentCount</span>(<span class="ident">u8</span>),
<span class="doccomment">/// An image can specify a zero height in the frame header and use the DNL (Define Number of</span>
<span class="doccomment">/// Lines) marker at the end of the first scan to define the number of lines in the frame.</span>
<span class="ident">DNL</span>,
<span class="doccomment">/// Subsampling ratio.</span>
<span class="ident">SubsamplingRatio</span>,
<span class="doccomment">/// A subsampling ratio not representable as an integer.</span>
<span class="ident">NonIntegerSubsamplingRatio</span>,
}
<span class="doccomment">/// Errors that can occur while decoding a JPEG image.</span>
<span class="attribute">#[<span class="ident">derive</span>(<span class="ident">Debug</span>)]</span>
<span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">Error</span> {
<span class="doccomment">/// The image is not formatted properly. The string contains detailed information about the</span>
<span class="doccomment">/// error.</span>
<span class="ident">Format</span>(<span class="ident">String</span>),
<span class="doccomment">/// The image makes use of a JPEG feature not (currently) supported by this library.</span>
<span class="ident">Unsupported</span>(<span class="ident">UnsupportedFeature</span>),
<span class="doccomment">/// An I/O error occurred while decoding the image.</span>
<span class="ident">Io</span>(<span class="ident">IoError</span>),
<span class="doccomment">/// An internal error occurred while decoding the image.</span>
<span class="ident">Internal</span>(<span class="ident">Box</span><span class="op"><</span><span class="ident">dyn</span> <span class="ident">StdError</span> <span class="op">+</span> <span class="ident">Send</span> <span class="op">+</span> <span class="ident">Sync</span> <span class="op">+</span> <span class="lifetime">'static</span><span class="op">></span>), <span class="comment">//TODO: not used, can be removed with the next version bump</span>
}
<span class="kw">impl</span> <span class="ident">fmt::Display</span> <span class="kw">for</span> <span class="ident">Error</span> {
<span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt::Formatter</span>) <span class="op">-</span><span class="op">></span> <span class="ident">fmt::Result</span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Error::Format</span>(<span class="kw-2">ref</span> <span class="ident">desc</span>) <span class="op">=</span><span class="op">></span> <span class="macro">write!</span>(<span class="ident">f</span>, <span class="string">"invalid JPEG format: {}"</span>, <span class="ident">desc</span>),
<span class="ident">Error::Unsupported</span>(<span class="kw-2">ref</span> <span class="ident">feat</span>) <span class="op">=</span><span class="op">></span> <span class="macro">write!</span>(<span class="ident">f</span>, <span class="string">"unsupported JPEG feature: {:?}"</span>, <span class="ident">feat</span>),
<span class="ident">Error::Io</span>(<span class="kw-2">ref</span> <span class="ident">err</span>) <span class="op">=</span><span class="op">></span> <span class="ident">err</span>.<span class="ident">fmt</span>(<span class="ident">f</span>),
<span class="ident">Error::Internal</span>(<span class="kw-2">ref</span> <span class="ident">err</span>) <span class="op">=</span><span class="op">></span> <span class="ident">err</span>.<span class="ident">fmt</span>(<span class="ident">f</span>),
}
}
}
<span class="kw">impl</span> <span class="ident">StdError</span> <span class="kw">for</span> <span class="ident">Error</span> {
<span class="kw">fn</span> <span class="ident">source</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-</span><span class="op">></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="kw-2">&</span>(<span class="ident">dyn</span> <span class="ident">StdError</span> <span class="op">+</span> <span class="lifetime">'static</span>)<span class="op">></span> {
<span class="kw">match</span> <span class="kw-2">*</span><span class="self">self</span> {
<span class="ident">Error::Io</span>(<span class="kw-2">ref</span> <span class="ident">err</span>) <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="ident">err</span>),
<span class="ident">Error::Internal</span>(<span class="kw-2">ref</span> <span class="ident">err</span>) <span class="op">=</span><span class="op">></span> <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="kw-2">*</span><span class="kw-2">*</span><span class="ident">err</span>),
<span class="kw">_</span> <span class="op">=</span><span class="op">></span> <span class="prelude-val">None</span>,
}
}
}
<span class="kw">impl</span> <span class="ident">From</span><span class="op"><</span><span class="ident">IoError</span><span class="op">></span> <span class="kw">for</span> <span class="ident">Error</span> {
<span class="kw">fn</span> <span class="ident">from</span>(<span class="ident">err</span>: <span class="ident">IoError</span>) <span class="op">-</span><span class="op">></span> <span class="ident">Error</span> {
<span class="ident">Error::Io</span>(<span class="ident">err</span>)
}
}
</pre></div>
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