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// Copyright 2014-2015 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // 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. /// As always - iOS on arm uses SjLj exceptions and /// _Unwind_Backtrace is even not available there. Still, /// backtraces could be extracted using a backtrace function, /// which thanks god is public /// /// As mentioned in a huge comment block in `super::super`, backtrace /// doesn't play well with green threads, so while it is extremely nice and /// simple to use it should be used only on iOS devices as the only viable /// option. use io; use libc; use sys::backtrace::BacktraceContext; use sys_common::backtrace::Frame; #[inline(never)] // if we know this is a function call, we can skip it when // tracing pub fn unwind_backtrace(frames: &mut [Frame]) -> io::Result<(usize, BacktraceContext)> { const FRAME_LEN: usize = 100; assert!(FRAME_LEN >= frames.len()); let mut raw_frames = [::ptr::null_mut(); FRAME_LEN]; let nb_frames = unsafe { backtrace(raw_frames.as_mut_ptr(), raw_frames.len() as libc::c_int) } as usize; for (from, to) in raw_frames.iter().zip(frames.iter_mut()).take(nb_frames) { *to = Frame { exact_position: *from as *mut u8, symbol_addr: *from as *mut u8, }; } Ok((nb_frames as usize, BacktraceContext)) } extern { fn backtrace(buf: *mut *mut libc::c_void, sz: libc::c_int) -> libc::c_int; }