<!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 to the Rust file `libstd/sys_common/gnu/libbacktrace.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>libbacktrace.rs.html -- 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="../../../../dark.css"><link rel="stylesheet" type="text/css" href="../../../../light.css" id="themeStyle"><script src="../../../../storage.js"></script><link rel="shortcut icon" href="https://doc.rust-lang.org/favicon.ico"></head><body class="rustdoc source"><!--[if lte IE 8]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="sidebar-menu">☰</div><a href='../../../../std/index.html'><img src='https://www.rust-lang.org/logos/rust-logo-128x128-blk-v2.png' alt='logo' width='100'></a></nav><div class="theme-picker"><button id="theme-picker" aria-label="Pick another theme!"><img src="../../../../brush.svg" width="18" alt="Pick another theme!"></button><div id="theme-choices"></div></div><script src="../../../../theme.js"></script><nav class="sub"><form class="search-form js-only"><div class="search-container"><input class="search-input" name="search" autocomplete="off" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><a id="settings-menu" href="../../../../settings.html"><img src="../../../../wheel.svg" width="18" alt="Change settings"></a></div></form></nav><section id="main" class="content"><pre class="line-numbers"><span id="1"> 1</span> <span id="2"> 2</span> <span id="3"> 3</span> <span id="4"> 4</span> <span id="5"> 5</span> <span id="6"> 6</span> <span id="7"> 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id="202">202</span> <span id="203">203</span> <span id="204">204</span> <span id="205">205</span> <span id="206">206</span> <span id="207">207</span> <span id="208">208</span> <span id="209">209</span> <span id="210">210</span> <span id="211">211</span> <span id="212">212</span> <span id="213">213</span> <span id="214">214</span> <span id="215">215</span> <span id="216">216</span> </pre><pre class="rust "> <span class="comment">// Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT</span> <span class="comment">// file at the top-level directory of this distribution and at</span> <span class="comment">// http://rust-lang.org/COPYRIGHT.</span> <span class="comment">//</span> <span class="comment">// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or</span> <span class="comment">// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span> <span class="comment">// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your</span> <span class="comment">// option. This file may not be copied, modified, or distributed</span> <span class="comment">// except according to those terms.</span> <span class="kw">use</span> <span class="ident">libc</span>; <span class="kw">use</span> <span class="ident">ffi</span>::<span class="ident">CStr</span>; <span class="kw">use</span> <span class="ident">io</span>; <span class="kw">use</span> <span class="ident">mem</span>; <span class="kw">use</span> <span class="ident">ptr</span>; <span class="kw">use</span> <span class="ident">sys</span>::<span class="ident">backtrace</span>::<span class="ident">BacktraceContext</span>; <span class="kw">use</span> <span class="ident">sys_common</span>::<span class="ident">backtrace</span>::<span class="ident">Frame</span>; <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">foreach_symbol_fileline</span><span class="op"><</span><span class="ident">F</span><span class="op">></span>(<span class="ident">frame</span>: <span class="ident">Frame</span>, <span class="kw-2">mut</span> <span class="ident">f</span>: <span class="ident">F</span>, <span class="kw">_</span>: <span class="kw-2">&</span><span class="ident">BacktraceContext</span>) <span class="op">-></span> <span class="ident">io</span>::<span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">bool</span><span class="op">></span> <span class="kw">where</span> <span class="ident">F</span>: <span class="ident">FnMut</span>(<span class="kw-2">&</span>[<span class="ident">u8</span>], <span class="ident">u32</span>) <span class="op">-></span> <span class="ident">io</span>::<span class="prelude-ty">Result</span><span class="op"><</span>()<span class="op">></span> { <span class="comment">// pcinfo may return an arbitrary number of file:line pairs,</span> <span class="comment">// in the order of stack trace (i.e. inlined calls first).</span> <span class="comment">// in order to avoid allocation, we stack-allocate a fixed size of entries.</span> <span class="kw">const</span> <span class="ident">FILELINE_SIZE</span>: <span class="ident">usize</span> <span class="op">=</span> <span class="number">32</span>; <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">fileline_buf</span> <span class="op">=</span> [(<span class="ident">ptr</span>::<span class="ident">null</span>(), <span class="op">!</span><span class="number">0</span>); <span class="ident">FILELINE_SIZE</span>]; <span class="kw">let</span> <span class="ident">ret</span>; <span class="kw">let</span> <span class="ident">fileline_count</span> <span class="op">=</span> { <span class="kw">let</span> <span class="ident">state</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">init_state</span>() }; <span class="kw">if</span> <span class="ident">state</span>.<span class="ident">is_null</span>() { <span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">io</span>::<span class="ident">Error</span>::<span class="ident">new</span>( <span class="ident">io</span>::<span class="ident">ErrorKind</span>::<span class="ident">Other</span>, <span class="string">"failed to allocate libbacktrace state"</span>) ) } <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">fileline_win</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> [<span class="ident">FileLine</span>] <span class="op">=</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fileline_buf</span>; <span class="kw">let</span> <span class="ident">fileline_addr</span> <span class="op">=</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fileline_win</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="kw-2">&</span><span class="kw-2">mut</span> [<span class="ident">FileLine</span>]; <span class="ident">ret</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">backtrace_pcinfo</span>(<span class="ident">state</span>, <span class="ident">frame</span>.<span class="ident">exact_position</span> <span class="kw">as</span> <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">pcinfo_cb</span>, <span class="ident">error_cb</span>, <span class="ident">fileline_addr</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>) }; <span class="ident">FILELINE_SIZE</span> <span class="op">-</span> <span class="ident">fileline_win</span>.<span class="ident">len</span>() }; <span class="kw">if</span> <span class="ident">ret</span> <span class="op">==</span> <span class="number">0</span> { <span class="kw">for</span> <span class="kw-2">&</span>(<span class="ident">file</span>, <span class="ident">line</span>) <span class="kw">in</span> <span class="kw-2">&</span><span class="ident">fileline_buf</span>[..<span class="ident">fileline_count</span>] { <span class="kw">if</span> <span class="ident">file</span>.<span class="ident">is_null</span>() { <span class="kw">continue</span>; } <span class="comment">// just to be sure</span> <span class="kw">let</span> <span class="ident">file</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">CStr</span>::<span class="ident">from_ptr</span>(<span class="ident">file</span>).<span class="ident">to_bytes</span>() }; <span class="ident">f</span>(<span class="ident">file</span>, <span class="ident">line</span>)<span class="question-mark">?</span>; } <span class="prelude-val">Ok</span>(<span class="ident">fileline_count</span> <span class="op">==</span> <span class="ident">FILELINE_SIZE</span>) } <span class="kw">else</span> { <span class="prelude-val">Ok</span>(<span class="bool-val">false</span>) } } <span class="doccomment">/// Converts a pointer to symbol to its string value.</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">resolve_symname</span><span class="op"><</span><span class="ident">F</span><span class="op">></span>(<span class="ident">frame</span>: <span class="ident">Frame</span>, <span class="ident">callback</span>: <span class="ident">F</span>, <span class="kw">_</span>: <span class="kw-2">&</span><span class="ident">BacktraceContext</span>) <span class="op">-></span> <span class="ident">io</span>::<span class="prelude-ty">Result</span><span class="op"><</span>()<span class="op">></span> <span class="kw">where</span> <span class="ident">F</span>: <span class="ident">FnOnce</span>(<span class="prelude-ty">Option</span><span class="op"><</span><span class="kw-2">&</span><span class="ident">str</span><span class="op">></span>) <span class="op">-></span> <span class="ident">io</span>::<span class="prelude-ty">Result</span><span class="op"><</span>()<span class="op">></span> { <span class="kw">let</span> <span class="ident">symname</span> <span class="op">=</span> { <span class="kw">let</span> <span class="ident">state</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">init_state</span>() }; <span class="kw">if</span> <span class="ident">state</span>.<span class="ident">is_null</span>() { <span class="kw">return</span> <span class="prelude-val">Err</span>(<span class="ident">io</span>::<span class="ident">Error</span>::<span class="ident">new</span>( <span class="ident">io</span>::<span class="ident">ErrorKind</span>::<span class="ident">Other</span>, <span class="string">"failed to allocate libbacktrace state"</span>) ) } <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">data</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span> <span class="op">=</span> <span class="ident">ptr</span>::<span class="ident">null</span>(); <span class="kw">let</span> <span class="ident">data_addr</span> <span class="op">=</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">data</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>; <span class="kw">let</span> <span class="ident">ret</span> <span class="op">=</span> <span class="kw">unsafe</span> { <span class="ident">backtrace_syminfo</span>(<span class="ident">state</span>, <span class="ident">frame</span>.<span class="ident">symbol_addr</span> <span class="kw">as</span> <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">syminfo_cb</span>, <span class="ident">error_cb</span>, <span class="ident">data_addr</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>) }; <span class="kw">if</span> <span class="ident">ret</span> <span class="op">==</span> <span class="number">0</span> <span class="op">||</span> <span class="ident">data</span>.<span class="ident">is_null</span>() { <span class="prelude-val">None</span> } <span class="kw">else</span> { <span class="kw">unsafe</span> { <span class="ident">CStr</span>::<span class="ident">from_ptr</span>(<span class="ident">data</span>).<span class="ident">to_str</span>().<span class="ident">ok</span>() } } }; <span class="ident">callback</span>(<span class="ident">symname</span>) } <span class="comment">////////////////////////////////////////////////////////////////////////</span> <span class="comment">// libbacktrace.h API</span> <span class="comment">////////////////////////////////////////////////////////////////////////</span> <span class="kw">type</span> <span class="ident">backtrace_syminfo_callback</span> <span class="op">=</span> <span class="kw">extern</span> <span class="string">"C"</span> <span class="kw">fn</span>(<span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">pc</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">symname</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">symval</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">symsize</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>); <span class="kw">type</span> <span class="ident">backtrace_full_callback</span> <span class="op">=</span> <span class="kw">extern</span> <span class="string">"C"</span> <span class="kw">fn</span>(<span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">pc</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">filename</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">lineno</span>: <span class="ident">libc</span>::<span class="ident">c_int</span>, <span class="ident">function</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>) <span class="op">-></span> <span class="ident">libc</span>::<span class="ident">c_int</span>; <span class="kw">type</span> <span class="ident">backtrace_error_callback</span> <span class="op">=</span> <span class="kw">extern</span> <span class="string">"C"</span> <span class="kw">fn</span>(<span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">msg</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">errnum</span>: <span class="ident">libc</span>::<span class="ident">c_int</span>); <span class="kw">enum</span> <span class="ident">backtrace_state</span> {} <span class="kw">extern</span> { <span class="kw">fn</span> <span class="ident">backtrace_create_state</span>(<span class="ident">filename</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">threaded</span>: <span class="ident">libc</span>::<span class="ident">c_int</span>, <span class="ident">error</span>: <span class="ident">backtrace_error_callback</span>, <span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>) <span class="op">-></span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">backtrace_state</span>; <span class="kw">fn</span> <span class="ident">backtrace_syminfo</span>(<span class="ident">state</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">backtrace_state</span>, <span class="ident">addr</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">cb</span>: <span class="ident">backtrace_syminfo_callback</span>, <span class="ident">error</span>: <span class="ident">backtrace_error_callback</span>, <span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>) <span class="op">-></span> <span class="ident">libc</span>::<span class="ident">c_int</span>; <span class="kw">fn</span> <span class="ident">backtrace_pcinfo</span>(<span class="ident">state</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">backtrace_state</span>, <span class="ident">addr</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">cb</span>: <span class="ident">backtrace_full_callback</span>, <span class="ident">error</span>: <span class="ident">backtrace_error_callback</span>, <span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>) <span class="op">-></span> <span class="ident">libc</span>::<span class="ident">c_int</span>; } <span class="comment">////////////////////////////////////////////////////////////////////////</span> <span class="comment">// helper callbacks</span> <span class="comment">////////////////////////////////////////////////////////////////////////</span> <span class="kw">type</span> <span class="ident">FileLine</span> <span class="op">=</span> (<span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">u32</span>); <span class="kw">extern</span> <span class="kw">fn</span> <span class="ident">error_cb</span>(<span class="ident">_data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">_msg</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">_errnum</span>: <span class="ident">libc</span>::<span class="ident">c_int</span>) { <span class="comment">// do nothing for now</span> } <span class="kw">extern</span> <span class="kw">fn</span> <span class="ident">syminfo_cb</span>(<span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">_pc</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">symname</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">_symval</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">_symsize</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>) { <span class="kw">let</span> <span class="ident">slot</span> <span class="op">=</span> <span class="ident">data</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>; <span class="kw">unsafe</span> { <span class="kw-2">*</span><span class="ident">slot</span> <span class="op">=</span> <span class="ident">symname</span>; } } <span class="kw">extern</span> <span class="kw">fn</span> <span class="ident">pcinfo_cb</span>(<span class="ident">data</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">libc</span>::<span class="ident">c_void</span>, <span class="ident">_pc</span>: <span class="ident">libc</span>::<span class="ident">uintptr_t</span>, <span class="ident">filename</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>, <span class="ident">lineno</span>: <span class="ident">libc</span>::<span class="ident">c_int</span>, <span class="ident">_function</span>: <span class="kw-2">*</span><span class="kw">const</span> <span class="ident">libc</span>::<span class="ident">c_char</span>) <span class="op">-></span> <span class="ident">libc</span>::<span class="ident">c_int</span> { <span class="kw">if</span> <span class="op">!</span><span class="ident">filename</span>.<span class="ident">is_null</span>() { <span class="kw">let</span> <span class="ident">slot</span> <span class="op">=</span> <span class="ident">data</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="kw-2">&</span><span class="kw-2">mut</span> [<span class="ident">FileLine</span>]; <span class="kw">let</span> <span class="ident">buffer</span> <span class="op">=</span> <span class="kw">unsafe</span> {<span class="ident">ptr</span>::<span class="ident">read</span>(<span class="ident">slot</span>)}; <span class="comment">// if the buffer is not full, add file:line to the buffer</span> <span class="comment">// and adjust the buffer for next possible calls to pcinfo_cb.</span> <span class="kw">if</span> <span class="op">!</span><span class="ident">buffer</span>.<span class="ident">is_empty</span>() { <span class="ident">buffer</span>[<span class="number">0</span>] <span class="op">=</span> (<span class="ident">filename</span>, <span class="ident">lineno</span> <span class="kw">as</span> <span class="ident">u32</span>); <span class="kw">unsafe</span> { <span class="ident">ptr</span>::<span class="ident">write</span>(<span class="ident">slot</span>, <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">buffer</span>[<span class="number">1</span>..]); } } } <span class="number">0</span> } <span class="comment">// The libbacktrace API supports creating a state, but it does not</span> <span class="comment">// support destroying a state. I personally take this to mean that a</span> <span class="comment">// state is meant to be created and then live forever.</span> <span class="comment">//</span> <span class="comment">// I would love to register an at_exit() handler which cleans up this</span> <span class="comment">// state, but libbacktrace provides no way to do so.</span> <span class="comment">//</span> <span class="comment">// With these constraints, this function has a statically cached state</span> <span class="comment">// that is calculated the first time this is requested. Remember that</span> <span class="comment">// backtracing all happens serially (one global lock).</span> <span class="comment">//</span> <span class="comment">// Things don't work so well on not-Linux since libbacktrace can't track</span> <span class="comment">// down that executable this is. We at one point used env::current_exe but</span> <span class="comment">// it turns out that there are some serious security issues with that</span> <span class="comment">// approach.</span> <span class="comment">//</span> <span class="comment">// Specifically, on certain platforms like BSDs, a malicious actor can cause</span> <span class="comment">// an arbitrary file to be placed at the path returned by current_exe.</span> <span class="comment">// libbacktrace does not behave defensively in the presence of ill-formed</span> <span class="comment">// DWARF information, and has been demonstrated to segfault in at least one</span> <span class="comment">// case. There is no evidence at the moment to suggest that a more carefully</span> <span class="comment">// constructed file can't cause arbitrary code execution. As a result of all</span> <span class="comment">// of this, we don't hint libbacktrace with the path to the current process.</span> <span class="kw">unsafe</span> <span class="kw">fn</span> <span class="ident">init_state</span>() <span class="op">-></span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">backtrace_state</span> { <span class="kw">static</span> <span class="kw-2">mut</span> <span class="ident">STATE</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">backtrace_state</span> <span class="op">=</span> <span class="ident">ptr</span>::<span class="ident">null_mut</span>(); <span class="kw">if</span> <span class="op">!</span><span class="ident">STATE</span>.<span class="ident">is_null</span>() { <span class="kw">return</span> <span class="ident">STATE</span> } <span class="kw">let</span> <span class="ident">filename</span> <span class="op">=</span> <span class="kw">match</span> ::<span class="ident">sys</span>::<span class="ident">backtrace</span>::<span class="ident">gnu</span>::<span class="ident">get_executable_filename</span>() { <span class="prelude-val">Ok</span>((<span class="ident">filename</span>, <span class="ident">file</span>)) <span class="op">=></span> { <span class="comment">// filename is purposely leaked here since libbacktrace requires</span> <span class="comment">// it to stay allocated permanently, file is also leaked so that</span> <span class="comment">// the file stays locked</span> <span class="kw">let</span> <span class="ident">filename_ptr</span> <span class="op">=</span> <span class="ident">filename</span>.<span class="ident">as_ptr</span>(); <span class="ident">mem</span>::<span class="ident">forget</span>(<span class="ident">filename</span>); <span class="ident">mem</span>::<span class="ident">forget</span>(<span class="ident">file</span>); <span class="ident">filename_ptr</span> }, <span class="prelude-val">Err</span>(<span class="kw">_</span>) <span class="op">=></span> <span class="ident">ptr</span>::<span class="ident">null</span>(), }; <span class="ident">STATE</span> <span class="op">=</span> <span class="ident">backtrace_create_state</span>(<span class="ident">filename</span>, <span class="number">0</span>, <span class="ident">error_cb</span>, <span class="ident">ptr</span>::<span class="ident">null_mut</span>()); <span class="ident">STATE</span> } </pre> </section><section id="search" class="content hidden"></section><section class="footer"></section><aside id="help" class="hidden"><div><h1 class="hidden">Help</h1><div class="shortcuts"><h2>Keyboard Shortcuts</h2><dl><dt><kbd>?</kbd></dt><dd>Show this help dialog</dd><dt><kbd>S</kbd></dt><dd>Focus the search field</dd><dt><kbd>↑</kbd></dt><dd>Move up in search results</dd><dt><kbd>↓</kbd></dt><dd>Move down in search results</dd><dt><kbd>↹</kbd></dt><dd>Switch tab</dd><dt><kbd>⏎</kbd></dt><dd>Go to active search result</dd><dt><kbd>+</kbd></dt><dd>Expand all sections</dd><dt><kbd>-</kbd></dt><dd>Collapse all sections</dd></dl></div><div class="infos"><h2>Search Tricks</h2><p>Prefix searches with a type followed by a colon (e.g. <code>fn:</code>) to restrict the search to a given type.</p><p>Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>.</p><p>Search functions by type signature (e.g. <code>vec -> usize</code> or <code>* -> vec</code>)</p><p>Search multiple things at once by splitting your query with comma (e.g. <code>str,u8</code> or <code>String,struct:Vec,test</code>)</p></div></div></aside><script>window.rootPath = "../../../../";window.currentCrate = "std";</script><script src="../../../../aliases.js"></script><script src="../../../../main.js"></script><script defer src="../../../../search-index.js"></script></body></html>