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use io;
use io::prelude::*;
use libc;
use mem;
use sync::StaticMutex;
use super::super::printing::print;
#[inline(never)]
pub fn write(w: &mut Write) -> io::Result<()> {
struct Context<'a> {
idx: isize,
writer: &'a mut (Write+'a),
last_error: Option<io::Error>,
}
static LOCK: StaticMutex = StaticMutex::new();
let _g = LOCK.lock();
writeln!(w, "stack backtrace:")?;
let mut cx = Context { writer: w, last_error: None, idx: 0 };
return match unsafe {
uw::_Unwind_Backtrace(trace_fn,
&mut cx as *mut Context as *mut libc::c_void)
} {
uw::_URC_NO_REASON => {
match cx.last_error {
Some(err) => Err(err),
None => Ok(())
}
}
_ => Ok(()),
};
extern fn trace_fn(ctx: *mut uw::_Unwind_Context,
arg: *mut libc::c_void) -> uw::_Unwind_Reason_Code {
let cx: &mut Context = unsafe { mem::transmute(arg) };
let mut ip_before_insn = 0;
let mut ip = unsafe {
uw::_Unwind_GetIPInfo(ctx, &mut ip_before_insn) as *mut libc::c_void
};
if !ip.is_null() && ip_before_insn == 0 {
ip = (ip as usize - 1) as *mut _;
}
let symaddr = if cfg!(target_os = "macos") || cfg!(target_os = "ios") {
ip
} else {
unsafe { uw::_Unwind_FindEnclosingFunction(ip) }
};
cx.idx += 1;
if cx.idx <= 0 { return uw::_URC_NO_REASON }
if cx.idx > 100 {
match write!(cx.writer, " ... <frames omitted>\n") {
Ok(()) => {}
Err(e) => { cx.last_error = Some(e); }
}
return uw::_URC_FAILURE
}
if cx.last_error.is_some() { return uw::_URC_FAILURE }
match print(cx.writer, cx.idx, ip, symaddr) {
Ok(()) => {}
Err(e) => { cx.last_error = Some(e); }
}
uw::_URC_NO_REASON
}
}
#[allow(non_camel_case_types)]
#[allow(non_snake_case)]
mod uw {
pub use self::_Unwind_Reason_Code::*;
use libc;
#[repr(C)]
pub enum _Unwind_Reason_Code {
_URC_NO_REASON = 0,
_URC_FOREIGN_EXCEPTION_CAUGHT = 1,
_URC_FATAL_PHASE2_ERROR = 2,
_URC_FATAL_PHASE1_ERROR = 3,
_URC_NORMAL_STOP = 4,
_URC_END_OF_STACK = 5,
_URC_HANDLER_FOUND = 6,
_URC_INSTALL_CONTEXT = 7,
_URC_CONTINUE_UNWIND = 8,
_URC_FAILURE = 9,
}
pub enum _Unwind_Context {}
pub type _Unwind_Trace_Fn =
extern fn(ctx: *mut _Unwind_Context,
arg: *mut libc::c_void) -> _Unwind_Reason_Code;
extern {
#[cfg(not(all(target_os = "ios", target_arch = "arm")))]
pub fn _Unwind_Backtrace(trace: _Unwind_Trace_Fn,
trace_argument: *mut libc::c_void)
-> _Unwind_Reason_Code;
#[cfg(all(not(all(target_os = "android", target_arch = "arm")),
not(all(target_os = "linux", target_arch = "arm"))))]
pub fn _Unwind_GetIPInfo(ctx: *mut _Unwind_Context,
ip_before_insn: *mut libc::c_int)
-> libc::uintptr_t;
#[cfg(all(not(target_os = "android"),
not(all(target_os = "linux", target_arch = "arm"))))]
pub fn _Unwind_FindEnclosingFunction(pc: *mut libc::c_void)
-> *mut libc::c_void;
}
#[cfg(any(all(target_os = "android", target_arch = "arm"),
all(target_os = "linux", target_arch = "arm")))]
pub unsafe fn _Unwind_GetIP(ctx: *mut _Unwind_Context) -> libc::uintptr_t {
#[repr(C)]
enum _Unwind_VRS_Result {
_UVRSR_OK = 0,
_UVRSR_NOT_IMPLEMENTED = 1,
_UVRSR_FAILED = 2,
}
#[repr(C)]
enum _Unwind_VRS_RegClass {
_UVRSC_CORE = 0,
_UVRSC_VFP = 1,
_UVRSC_FPA = 2,
_UVRSC_WMMXD = 3,
_UVRSC_WMMXC = 4,
}
#[repr(C)]
enum _Unwind_VRS_DataRepresentation {
_UVRSD_UINT32 = 0,
_UVRSD_VFPX = 1,
_UVRSD_FPAX = 2,
_UVRSD_UINT64 = 3,
_UVRSD_FLOAT = 4,
_UVRSD_DOUBLE = 5,
}
type _Unwind_Word = libc::c_uint;
extern {
fn _Unwind_VRS_Get(ctx: *mut _Unwind_Context,
klass: _Unwind_VRS_RegClass,
word: _Unwind_Word,
repr: _Unwind_VRS_DataRepresentation,
data: *mut libc::c_void)
-> _Unwind_VRS_Result;
}
let mut val: _Unwind_Word = 0;
let ptr = &mut val as *mut _Unwind_Word;
let _ = _Unwind_VRS_Get(ctx, _Unwind_VRS_RegClass::_UVRSC_CORE, 15,
_Unwind_VRS_DataRepresentation::_UVRSD_UINT32,
ptr as *mut libc::c_void);
(val & !1) as libc::uintptr_t
}
#[cfg(any(all(target_os = "android", target_arch = "arm"),
all(target_os = "linux", target_arch = "arm")))]
pub unsafe fn _Unwind_GetIPInfo(ctx: *mut _Unwind_Context,
ip_before_insn: *mut libc::c_int)
-> libc::uintptr_t
{
*ip_before_insn = 0;
_Unwind_GetIP(ctx)
}
#[cfg(any(target_os = "android",
all(target_os = "linux", target_arch = "arm")))]
pub unsafe fn _Unwind_FindEnclosingFunction(pc: *mut libc::c_void)
-> *mut libc::c_void
{
pc
}
}