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#![allow(deprecated)]
use io;
use libc::c_void;
use mem;
use ptr;
use sys::c;
use sys::dynamic_lib::DynamicLibrary;
use sys_common::backtrace::Frame;
macro_rules! sym {
($lib:expr, $e:expr, $t:ident) => (
$lib.symbol($e).map(|f| unsafe {
$crate::mem::transmute::<usize, $t>(f)
})
)
}
mod printing;
#[cfg(target_env = "gnu")]
#[path = "backtrace_gnu.rs"]
pub mod gnu;
pub use self::printing::{resolve_symname, foreach_symbol_fileline};
pub fn unwind_backtrace(frames: &mut [Frame])
-> io::Result<(usize, BacktraceContext)>
{
let dbghelp = DynamicLibrary::open("dbghelp.dll")?;
let SymInitialize = sym!(dbghelp, "SymInitialize", SymInitializeFn)?;
let SymCleanup = sym!(dbghelp, "SymCleanup", SymCleanupFn)?;
let StackWalk64 = sym!(dbghelp, "StackWalk64", StackWalk64Fn)?;
let process = unsafe { c::GetCurrentProcess() };
let thread = unsafe { c::GetCurrentThread() };
let mut context: c::CONTEXT = unsafe { mem::zeroed() };
unsafe { c::RtlCaptureContext(&mut context) };
let mut frame: c::STACKFRAME64 = unsafe { mem::zeroed() };
let image = init_frame(&mut frame, &context);
let backtrace_context = BacktraceContext {
handle: process,
SymCleanup,
dbghelp,
};
let ret = unsafe { SymInitialize(process, ptr::null_mut(), c::TRUE) };
if ret != c::TRUE {
return Ok((0, backtrace_context))
}
let mut i = 0;
unsafe {
while i < frames.len() &&
StackWalk64(image, process, thread, &mut frame, &mut context,
ptr::null_mut(),
ptr::null_mut(),
ptr::null_mut(),
ptr::null_mut()) == c::TRUE
{
let addr = frame.AddrPC.Offset;
if addr == frame.AddrReturn.Offset || addr == 0 ||
frame.AddrReturn.Offset == 0 { break }
frames[i] = Frame {
symbol_addr: (addr - 1) as *const u8,
exact_position: (addr - 1) as *const u8,
};
i += 1;
}
}
Ok((i, backtrace_context))
}
type SymInitializeFn =
unsafe extern "system" fn(c::HANDLE, *mut c_void,
c::BOOL) -> c::BOOL;
type SymCleanupFn =
unsafe extern "system" fn(c::HANDLE) -> c::BOOL;
type StackWalk64Fn =
unsafe extern "system" fn(c::DWORD, c::HANDLE, c::HANDLE,
*mut c::STACKFRAME64, *mut c::CONTEXT,
*mut c_void, *mut c_void,
*mut c_void, *mut c_void) -> c::BOOL;
#[cfg(target_arch = "x86")]
fn init_frame(frame: &mut c::STACKFRAME64,
ctx: &c::CONTEXT) -> c::DWORD {
frame.AddrPC.Offset = ctx.Eip as u64;
frame.AddrPC.Mode = c::ADDRESS_MODE::AddrModeFlat;
frame.AddrStack.Offset = ctx.Esp as u64;
frame.AddrStack.Mode = c::ADDRESS_MODE::AddrModeFlat;
frame.AddrFrame.Offset = ctx.Ebp as u64;
frame.AddrFrame.Mode = c::ADDRESS_MODE::AddrModeFlat;
c::IMAGE_FILE_MACHINE_I386
}
#[cfg(target_arch = "x86_64")]
fn init_frame(frame: &mut c::STACKFRAME64,
ctx: &c::CONTEXT) -> c::DWORD {
frame.AddrPC.Offset = ctx.Rip as u64;
frame.AddrPC.Mode = c::ADDRESS_MODE::AddrModeFlat;
frame.AddrStack.Offset = ctx.Rsp as u64;
frame.AddrStack.Mode = c::ADDRESS_MODE::AddrModeFlat;
frame.AddrFrame.Offset = ctx.Rbp as u64;
frame.AddrFrame.Mode = c::ADDRESS_MODE::AddrModeFlat;
c::IMAGE_FILE_MACHINE_AMD64
}
pub struct BacktraceContext {
handle: c::HANDLE,
SymCleanup: SymCleanupFn,
#[allow(dead_code)]
dbghelp: DynamicLibrary,
}
impl Drop for BacktraceContext {
fn drop(&mut self) {
unsafe { (self.SymCleanup)(self.handle); }
}
}