mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
f68d4d39f7
rust/src/libstd/rt/backtrace.rs
Alex Crichton dae48a07f3 Register new snapshots 
Also convert a number of `static mut` to just a plain old `static` and remove
some unsafe blocks.
2014-10-10 22:09:49 -07:00

1043 lines
39 KiB
Rust
Raw Blame History

// Copyright 2014 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.
//! Simple backtrace functionality (to print on failure)
#![allow(non_camel_case_types)]
use collections::Collection;
use from_str::from_str;
use io::{IoResult, Writer};
use iter::Iterator;
use option::{Some, None};
use os;
use result::{Ok, Err};
use str::StrSlice;
use sync::atomic;
use unicode::char::UnicodeChar;
pub use self::imp::write;
// For now logging is turned off by default, and this function checks to see
// whether the magical environment variable is present to see if it's turned on.
pub fn log_enabled() -> bool {
static ENABLED: atomic::AtomicInt = atomic::INIT_ATOMIC_INT;
match ENABLED.load(atomic::SeqCst) {
1 => return false,
2 => return true,
_ => {}
}
let val = match os::getenv("RUST_BACKTRACE") {
Some(..) => 2,
None => 1,
};
ENABLED.store(val, atomic::SeqCst);
val == 2
}
#[cfg(target_word_size = "64")] const HEX_WIDTH: uint = 18;
#[cfg(target_word_size = "32")] const HEX_WIDTH: uint = 10;
// All rust symbols are in theory lists of "::"-separated identifiers. Some
// assemblers, however, can't handle these characters in symbol names. To get
// around this, we use C++-style mangling. The mangling method is:
//
// 1. Prefix the symbol with "_ZN"
// 2. For each element of the path, emit the length plus the element
// 3. End the path with "E"
//
// For example, "_ZN4testE" => "test" and "_ZN3foo3bar" => "foo::bar".
//
// We're the ones printing our backtraces, so we can't rely on anything else to
// demangle our symbols. It's *much* nicer to look at demangled symbols, so
// this function is implemented to give us nice pretty output.
//
// Note that this demangler isn't quite as fancy as it could be. We have lots
// of other information in our symbols like hashes, version, type information,
// etc. Additionally, this doesn't handle glue symbols at all.
fn demangle(writer: &mut Writer, s: &str) -> IoResult<()> {
// First validate the symbol. If it doesn't look like anything we're
// expecting, we just print it literally. Note that we must handle non-rust
// symbols because we could have any function in the backtrace.
let mut valid = true;
if s.len() > 4 && s.starts_with("_ZN") && s.ends_with("E") {
let mut chars = s.slice(3, s.len() - 1).chars();
while valid {
let mut i = 0;
for c in chars {
if c.is_digit() {
i = i * 10 + c as uint - '0' as uint;
} else {
break
}
}
if i == 0 {
valid = chars.next().is_none();
break
} else if chars.by_ref().take(i - 1).count() != i - 1 {
valid = false;
}
}
} else {
valid = false;
}
// Alright, let's do this.
if !valid {
try!(writer.write_str(s));
} else {
let mut s = s.slice_from(3);
let mut first = true;
while s.len() > 1 {
if !first {
try!(writer.write_str("::"));
} else {
first = false;
}
let mut rest = s;
while rest.char_at(0).is_digit() {
rest = rest.slice_from(1);
}
let i: uint = from_str(s.slice_to(s.len() - rest.len())).unwrap();
s = rest.slice_from(i);
rest = rest.slice_to(i);
while rest.len() > 0 {
if rest.starts_with("$") {
macro_rules! demangle(
($($pat:expr => $demangled:expr),*) => ({
$(if rest.starts_with($pat) {
try!(writer.write_str($demangled));
rest = rest.slice_from($pat.len());
} else)*
{
try!(writer.write_str(rest));
break;
}
})
)
// see src/librustc/back/link.rs for these mappings
demangle! (
"$SP$" => "@",
"$UP$" => "Box",
"$RP$" => "*",
"$BP$" => "&",
"$LT$" => "<",
"$GT$" => ">",
"$LP$" => "(",
"$RP$" => ")",
"$C$" => ",",
// in theory we can demangle any Unicode code point, but
// for simplicity we just catch the common ones.
"$x20" => " ",
"$x27" => "'",
"$x5b" => "[",
"$x5d" => "]"
)
} else {
let idx = match rest.find('$') {
None => rest.len(),
Some(i) => i,
};
try!(writer.write_str(rest.slice_to(idx)));
rest = rest.slice_from(idx);
}
}
}
}
Ok(())
}
/// Backtrace support built on libgcc with some extra OS-specific support
///
/// Some methods of getting a backtrace:
///
/// * The backtrace() functions on unix. It turns out this doesn't work very
/// well for green threads on OSX, and the address to symbol portion of it
/// suffers problems that are described below.
///
/// * Using libunwind. This is more difficult than it sounds because libunwind
/// isn't installed everywhere by default. It's also a bit of a hefty library,
/// so possibly not the best option. When testing, libunwind was excellent at
/// getting both accurate backtraces and accurate symbols across platforms.
/// This route was not chosen in favor of the next option, however.
///
/// * We're already using libgcc_s for exceptions in rust (triggering task
/// unwinding and running destructors on the stack), and it turns out that it
/// conveniently comes with a function that also gives us a backtrace. All of
/// these functions look like _Unwind_*, but it's not quite the full
/// repertoire of the libunwind API. Due to it already being in use, this was
/// the chosen route of getting a backtrace.
///
/// After choosing libgcc_s for backtraces, the sad part is that it will only
/// give us a stack trace of instruction pointers. Thankfully these instruction
/// pointers are accurate (they work for green and native threads), but it's
/// then up to us again to figure out how to translate these addresses to
/// symbols. As with before, we have a few options. Before, that, a little bit
/// of an interlude about symbols. This is my very limited knowledge about
/// symbol tables, and this information is likely slightly wrong, but the
/// general idea should be correct.
///
/// When talking about symbols, it's helpful to know a few things about where
/// symbols are located. Some symbols are located in the dynamic symbol table
/// of the executable which in theory means that they're available for dynamic
/// linking and lookup. Other symbols end up only in the local symbol table of
/// the file. This loosely corresponds to pub and priv functions in Rust.
///
/// Armed with this knowledge, we know that our solution for address to symbol
/// translation will need to consult both the local and dynamic symbol tables.
/// With that in mind, here's our options of translating an address to
/// a symbol.
///
/// * Use dladdr(). The original backtrace()-based idea actually uses dladdr()
/// behind the scenes to translate, and this is why backtrace() was not used.
/// Conveniently, this method works fantastically on OSX. It appears dladdr()
/// uses magic to consult the local symbol table, or we're putting everything
/// in the dynamic symbol table anyway. Regardless, for OSX, this is the
/// method used for translation. It's provided by the system and easy to do.o
///
/// Sadly, all other systems have a dladdr() implementation that does not
/// consult the local symbol table. This means that most functions are blank
/// because they don't have symbols. This means that we need another solution.
///
/// * Use unw_get_proc_name(). This is part of the libunwind api (not the
/// libgcc_s version of the libunwind api), but involves taking a dependency
/// to libunwind. We may pursue this route in the future if we bundle
/// libunwind, but libunwind was unwieldy enough that it was not chosen at
/// this time to provide this functionality.
///
/// * Shell out to a utility like `readelf`. Crazy though it may sound, it's a
/// semi-reasonable solution. The stdlib already knows how to spawn processes,
/// so in theory it could invoke readelf, parse the output, and consult the
/// local/dynamic symbol tables from there. This ended up not getting chosen
/// due to the craziness of the idea plus the advent of the next option.
///
/// * Use `libbacktrace`. It turns out that this is a small library bundled in
/// the gcc repository which provides backtrace and symbol translation
/// functionality. All we really need from it is the backtrace functionality,
/// and we only really need this on everything that's not OSX, so this is the
/// chosen route for now.
///
/// In summary, the current situation uses libgcc_s to get a trace of stack
/// pointers, and we use dladdr() or libbacktrace to translate these addresses
/// to symbols. This is a bit of a hokey implementation as-is, but it works for
/// all unix platforms we support right now, so it at least gets the job done.
#[cfg(unix)]
mod imp {
use c_str::CString;
use io::{IoResult, Writer};
use libc;
use mem;
use option::{Some, None, Option};
use result::{Ok, Err};
use rt::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
/// 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 above, 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.
#[cfg(all(target_os = "ios", target_arch = "arm"))]
#[inline(never)]
pub fn write(w: &mut Writer) -> IoResult<()> {
use iter::{Iterator, range};
use result;
use slice::{MutableSlice};
extern {
fn backtrace(buf: *mut *mut libc::c_void,
sz: libc::c_int) -> libc::c_int;
}
// while it doesn't requires lock for work as everything is
// local, it still displays much nicer backtraces when a
// couple of tasks fail simultaneously
static LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
let _g = unsafe { LOCK.lock() };
try!(writeln!(w, "stack backtrace:"));
// 100 lines should be enough
const SIZE: uint = 100;
let mut buf: [*mut libc::c_void, ..SIZE] = unsafe {mem::zeroed()};
let cnt = unsafe { backtrace(buf.as_mut_ptr(), SIZE as libc::c_int) as uint};
// skipping the first one as it is write itself
let iter = range(1, cnt).map(|i| {
print(w, i as int, buf[i])
});
result::fold(iter, (), |_, _| ())
}
#[cfg(not(all(target_os = "ios", target_arch = "arm")))]
#[inline(never)] // if we know this is a function call, we can skip it when
// tracing
pub fn write(w: &mut Writer) -> IoResult<()> {
use io::IoError;
struct Context<'a> {
idx: int,
writer: &'a mut Writer+'a,
last_error: Option<IoError>,
}
// When using libbacktrace, we use some necessary global state, so we
// need to prevent more than one thread from entering this block. This
// is semi-reasonable in terms of printing anyway, and we know that all
// I/O done here is blocking I/O, not green I/O, so we don't have to
// worry about this being a native vs green mutex.
static LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
let _g = unsafe { LOCK.lock() };
try!(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 ip = unsafe { uw::_Unwind_GetIP(ctx) as *mut libc::c_void };
// dladdr() on osx gets whiny when we use FindEnclosingFunction, and
// it appears to work fine without it, so we only use
// FindEnclosingFunction on non-osx platforms. In doing so, we get a
// slightly more accurate stack trace in the process.
//
// This is often because failure involves the last instruction of a
// function being "call std::rt::begin_unwind", with no ret
// instructions after it. This means that the return instruction
// pointer points *outside* of the calling function, and by
// unwinding it we go back to the original function.
let ip = if cfg!(target_os = "macos") || cfg!(target_os = "ios") {
ip
} else {
unsafe { uw::_Unwind_FindEnclosingFunction(ip) }
};
// Don't print out the first few frames (they're not user frames)
cx.idx += 1;
if cx.idx <= 0 { return uw::_URC_NO_REASON }
// Don't print ginormous backtraces
if cx.idx > 100 {
match write!(cx.writer, " ... <frames omitted>\n") {
Ok(()) => {}
Err(e) => { cx.last_error = Some(e); }
}
return uw::_URC_FAILURE
}
// Once we hit an error, stop trying to print more frames
if cx.last_error.is_some() { return uw::_URC_FAILURE }
match print(cx.writer, cx.idx, ip) {
Ok(()) => {}
Err(e) => { cx.last_error = Some(e); }
}
// keep going
return uw::_URC_NO_REASON
}
}
#[cfg(any(target_os = "macos", target_os = "ios"))]
fn print(w: &mut Writer, idx: int, addr: *mut libc::c_void) -> IoResult<()> {
use intrinsics;
#[repr(C)]
struct Dl_info {
dli_fname: *const libc::c_char,
dli_fbase: *mut libc::c_void,
dli_sname: *const libc::c_char,
dli_saddr: *mut libc::c_void,
}
extern {
fn dladdr(addr: *const libc::c_void,
info: *mut Dl_info) -> libc::c_int;
}
let mut info: Dl_info = unsafe { intrinsics::init() };
if unsafe { dladdr(addr as *const libc::c_void, &mut info) == 0 } {
output(w, idx,addr, None)
} else {
output(w, idx, addr, Some(unsafe {
CString::new(info.dli_sname, false)
}))
}
}
#[cfg(not(any(target_os = "macos", target_os = "ios")))]
fn print(w: &mut Writer, idx: int, addr: *mut libc::c_void) -> IoResult<()> {
use collections::Collection;
use iter::Iterator;
use os;
use path::GenericPath;
use ptr::RawPtr;
use ptr;
use slice::{ImmutableSlice, MutableSlice};
////////////////////////////////////////////////////////////////////////
// libbacktrace.h API
////////////////////////////////////////////////////////////////////////
type backtrace_syminfo_callback =
extern "C" fn(data: *mut libc::c_void,
pc: libc::uintptr_t,
symname: *const libc::c_char,
symval: libc::uintptr_t,
symsize: libc::uintptr_t);
type backtrace_error_callback =
extern "C" fn(data: *mut libc::c_void,
msg: *const libc::c_char,
errnum: libc::c_int);
enum backtrace_state {}
#[link(name = "backtrace", kind = "static")]
#[cfg(not(test))]
extern {}
extern {
fn backtrace_create_state(filename: *const libc::c_char,
threaded: libc::c_int,
error: backtrace_error_callback,
data: *mut libc::c_void)
-> *mut backtrace_state;
fn backtrace_syminfo(state: *mut backtrace_state,
addr: libc::uintptr_t,
cb: backtrace_syminfo_callback,
error: backtrace_error_callback,
data: *mut libc::c_void) -> libc::c_int;
}
////////////////////////////////////////////////////////////////////////
// helper callbacks
////////////////////////////////////////////////////////////////////////
extern fn error_cb(_data: *mut libc::c_void, _msg: *const libc::c_char,
_errnum: libc::c_int) {
// do nothing for now
}
extern fn syminfo_cb(data: *mut libc::c_void,
_pc: libc::uintptr_t,
symname: *const libc::c_char,
_symval: libc::uintptr_t,
_symsize: libc::uintptr_t) {
let slot = data as *mut *const libc::c_char;
unsafe { *slot = symname; }
}
// The libbacktrace API supports creating a state, but it does not
// support destroying a state. I personally take this to mean that a
// state is meant to be created and then live forever.
//
// I would love to register an at_exit() handler which cleans up this
// state, but libbacktrace provides no way to do so.
//
// With these constraints, this function has a statically cached state
// that is calculated the first time this is requested. Remember that
// backtracing all happens serially (one global lock).
//
// An additionally oddity in this function is that we initialize the
// filename via self_exe_name() to pass to libbacktrace. It turns out
// that on Linux libbacktrace seamlessly gets the filename of the
// current executable, but this fails on freebsd. by always providing
// it, we make sure that libbacktrace never has a reason to not look up
// the symbols. The libbacktrace API also states that the filename must
// be in "permanent memory", so we copy it to a static and then use the
// static as the pointer.
//
// FIXME: We also call self_exe_name() on DragonFly BSD. I haven't
// tested if this is required or not.
unsafe fn init_state() -> *mut backtrace_state {
static mut STATE: *mut backtrace_state = 0 as *mut backtrace_state;
static mut LAST_FILENAME: [libc::c_char, ..256] = [0, ..256];
if !STATE.is_null() { return STATE }
let selfname = if cfg!(target_os = "freebsd") ||
cfg!(target_os = "dragonfly") {
os::self_exe_name()
} else {
None
};
let filename = match selfname {
Some(path) => {
let bytes = path.as_vec();
if bytes.len() < LAST_FILENAME.len() {
let i = bytes.iter();
for (slot, val) in LAST_FILENAME.iter_mut().zip(i) {
*slot = *val as libc::c_char;
}
LAST_FILENAME.as_ptr()
} else {
ptr::null()
}
}
None => ptr::null(),
};
STATE = backtrace_create_state(filename, 0, error_cb,
ptr::null_mut());
return STATE
}
////////////////////////////////////////////////////////////////////////
// translation
////////////////////////////////////////////////////////////////////////
// backtrace errors are currently swept under the rug, only I/O
// errors are reported
let state = unsafe { init_state() };
if state.is_null() {
return output(w, idx, addr, None)
}
let mut data = 0 as *const libc::c_char;
let data_addr = &mut data as *mut *const libc::c_char;
let ret = unsafe {
backtrace_syminfo(state, addr as libc::uintptr_t,
syminfo_cb, error_cb,
data_addr as *mut libc::c_void)
};
if ret == 0 || data.is_null() {
output(w, idx, addr, None)
} else {
output(w, idx, addr, Some(unsafe { CString::new(data, false) }))
}
}
// Finally, after all that work above, we can emit a symbol.
fn output(w: &mut Writer, idx: int, addr: *mut libc::c_void,
s: Option<CString>) -> IoResult<()> {
try!(write!(w, " {:2}: {:2$} - ", idx, addr, super::HEX_WIDTH));
match s.as_ref().and_then(|c| c.as_str()) {
Some(string) => try!(super::demangle(w, string)),
None => try!(write!(w, "<unknown>")),
}
w.write(['\n' as u8])
}
/// Unwind library interface used for backtraces
///
/// Note that the native libraries come from librustrt, not this
/// module.
/// Note that dead code is allowed as here are just bindings
/// iOS doesn't use all of them it but adding more
/// platform-specific configs pollutes the code too much
#[allow(non_camel_case_types)]
#[allow(non_snake_case)]
#[allow(dead_code)]
mod uw {
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, // used only by ARM EABI
}
pub enum _Unwind_Context {}
pub type _Unwind_Trace_Fn =
extern fn(ctx: *mut _Unwind_Context,
arg: *mut libc::c_void) -> _Unwind_Reason_Code;
extern {
// No native _Unwind_Backtrace on iOS
#[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(target_os = "android"),
not(all(target_os = "linux", target_arch = "arm"))))]
pub fn _Unwind_GetIP(ctx: *mut _Unwind_Context) -> 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;
}
// On android, the function _Unwind_GetIP is a macro, and this is the
// expansion of the macro. This is all copy/pasted directly from the
// header file with the definition of _Unwind_GetIP.
#[cfg(any(target_os = "android",
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, _UVRSC_CORE, 15, _UVRSD_UINT32,
ptr as *mut libc::c_void);
(val & !1) as libc::uintptr_t
}
// This function also doesn't exist on Android or ARM/Linux, so make it
// a no-op
#[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
}
}
}
/// As always, windows has something very different than unix, we mainly want
/// to avoid having to depend too much on libunwind for windows.
///
/// If you google around, you'll find a fair bit of references to built-in
/// functions to get backtraces on windows. It turns out that most of these are
/// in an external library called dbghelp. I was unable to find this library
/// via `-ldbghelp`, but it is apparently normal to do the `dlopen` equivalent
/// of it.
///
/// You'll also find that there's a function called CaptureStackBackTrace
/// mentioned frequently (which is also easy to use), but sadly I didn't have a
/// copy of that function in my mingw install (maybe it was broken?). Instead,
/// this takes the route of using StackWalk64 in order to walk the stack.
#[cfg(windows)]
#[allow(dead_code, non_snake_case)]
mod imp {
use c_str::CString;
use core_collections::Collection;
use intrinsics;
use io::{IoResult, Writer};
use libc;
use mem;
use ops::Drop;
use option::{Some, None};
use path::Path;
use result::{Ok, Err};
use rt::mutex::{StaticNativeMutex, NATIVE_MUTEX_INIT};
use slice::ImmutableSlice;
use str::StrSlice;
use dynamic_lib::DynamicLibrary;
#[allow(non_snake_case)]
extern "system" {
fn GetCurrentProcess() -> libc::HANDLE;
fn GetCurrentThread() -> libc::HANDLE;
fn RtlCaptureContext(ctx: *mut arch::CONTEXT);
}
type SymFromAddrFn =
extern "system" fn(libc::HANDLE, u64, *mut u64,
*mut SYMBOL_INFO) -> libc::BOOL;
type SymInitializeFn =
extern "system" fn(libc::HANDLE, *mut libc::c_void,
libc::BOOL) -> libc::BOOL;
type SymCleanupFn =
extern "system" fn(libc::HANDLE) -> libc::BOOL;
type StackWalk64Fn =
extern "system" fn(libc::DWORD, libc::HANDLE, libc::HANDLE,
*mut STACKFRAME64, *mut arch::CONTEXT,
*mut libc::c_void, *mut libc::c_void,
*mut libc::c_void, *mut libc::c_void) -> libc::BOOL;
const MAX_SYM_NAME: uint = 2000;
const IMAGE_FILE_MACHINE_I386: libc::DWORD = 0x014c;
const IMAGE_FILE_MACHINE_IA64: libc::DWORD = 0x0200;
const IMAGE_FILE_MACHINE_AMD64: libc::DWORD = 0x8664;
#[repr(C)]
struct SYMBOL_INFO {
SizeOfStruct: libc::c_ulong,
TypeIndex: libc::c_ulong,
Reserved: [u64, ..2],
Index: libc::c_ulong,
Size: libc::c_ulong,
ModBase: u64,
Flags: libc::c_ulong,
Value: u64,
Address: u64,
Register: libc::c_ulong,
Scope: libc::c_ulong,
Tag: libc::c_ulong,
NameLen: libc::c_ulong,
MaxNameLen: libc::c_ulong,
// note that windows has this as 1, but it basically just means that
// the name is inline at the end of the struct. For us, we just bump
// the struct size up to MAX_SYM_NAME.
Name: [libc::c_char, ..MAX_SYM_NAME],
}
#[repr(C)]
enum ADDRESS_MODE {
AddrMode1616,
AddrMode1632,
AddrModeReal,
AddrModeFlat,
}
struct ADDRESS64 {
Offset: u64,
Segment: u16,
Mode: ADDRESS_MODE,
}
struct STACKFRAME64 {
AddrPC: ADDRESS64,
AddrReturn: ADDRESS64,
AddrFrame: ADDRESS64,
AddrStack: ADDRESS64,
AddrBStore: ADDRESS64,
FuncTableEntry: *mut libc::c_void,
Params: [u64, ..4],
Far: libc::BOOL,
Virtual: libc::BOOL,
Reserved: [u64, ..3],
KdHelp: KDHELP64,
}
struct KDHELP64 {
Thread: u64,
ThCallbackStack: libc::DWORD,
ThCallbackBStore: libc::DWORD,
NextCallback: libc::DWORD,
FramePointer: libc::DWORD,
KiCallUserMode: u64,
KeUserCallbackDispatcher: u64,
SystemRangeStart: u64,
KiUserExceptionDispatcher: u64,
StackBase: u64,
StackLimit: u64,
Reserved: [u64, ..5],
}
#[cfg(target_arch = "x86")]
mod arch {
use libc;
const MAXIMUM_SUPPORTED_EXTENSION: uint = 512;
#[repr(C)]
pub struct CONTEXT {
ContextFlags: libc::DWORD,
Dr0: libc::DWORD,
Dr1: libc::DWORD,
Dr2: libc::DWORD,
Dr3: libc::DWORD,
Dr6: libc::DWORD,
Dr7: libc::DWORD,
FloatSave: FLOATING_SAVE_AREA,
SegGs: libc::DWORD,
SegFs: libc::DWORD,
SegEs: libc::DWORD,
SegDs: libc::DWORD,
Edi: libc::DWORD,
Esi: libc::DWORD,
Ebx: libc::DWORD,
Edx: libc::DWORD,
Ecx: libc::DWORD,
Eax: libc::DWORD,
Ebp: libc::DWORD,
Eip: libc::DWORD,
SegCs: libc::DWORD,
EFlags: libc::DWORD,
Esp: libc::DWORD,
SegSs: libc::DWORD,
ExtendedRegisters: [u8, ..MAXIMUM_SUPPORTED_EXTENSION],
}
#[repr(C)]
pub struct FLOATING_SAVE_AREA {
ControlWord: libc::DWORD,
StatusWord: libc::DWORD,
TagWord: libc::DWORD,
ErrorOffset: libc::DWORD,
ErrorSelector: libc::DWORD,
DataOffset: libc::DWORD,
DataSelector: libc::DWORD,
RegisterArea: [u8, ..80],
Cr0NpxState: libc::DWORD,
}
pub fn init_frame(frame: &mut super::STACKFRAME64,
ctx: &CONTEXT) -> libc::DWORD {
frame.AddrPC.Offset = ctx.Eip as u64;
frame.AddrPC.Mode = super::AddrModeFlat;
frame.AddrStack.Offset = ctx.Esp as u64;
frame.AddrStack.Mode = super::AddrModeFlat;
frame.AddrFrame.Offset = ctx.Ebp as u64;
frame.AddrFrame.Mode = super::AddrModeFlat;
super::IMAGE_FILE_MACHINE_I386
}
}
#[cfg(target_arch = "x86_64")]
mod arch {
use libc::{c_longlong, c_ulonglong};
use libc::types::os::arch::extra::{WORD, DWORD, DWORDLONG};
use simd;
#[repr(C)]
pub struct CONTEXT {
_align_hack: [simd::u64x2, ..0], // FIXME align on 16-byte
P1Home: DWORDLONG,
P2Home: DWORDLONG,
P3Home: DWORDLONG,
P4Home: DWORDLONG,
P5Home: DWORDLONG,
P6Home: DWORDLONG,
ContextFlags: DWORD,
MxCsr: DWORD,
SegCs: WORD,
SegDs: WORD,
SegEs: WORD,
SegFs: WORD,
SegGs: WORD,
SegSs: WORD,
EFlags: DWORD,
Dr0: DWORDLONG,
Dr1: DWORDLONG,
Dr2: DWORDLONG,
Dr3: DWORDLONG,
Dr6: DWORDLONG,
Dr7: DWORDLONG,
Rax: DWORDLONG,
Rcx: DWORDLONG,
Rdx: DWORDLONG,
Rbx: DWORDLONG,
Rsp: DWORDLONG,
Rbp: DWORDLONG,
Rsi: DWORDLONG,
Rdi: DWORDLONG,
R8: DWORDLONG,
R9: DWORDLONG,
R10: DWORDLONG,
R11: DWORDLONG,
R12: DWORDLONG,
R13: DWORDLONG,
R14: DWORDLONG,
R15: DWORDLONG,
Rip: DWORDLONG,
FltSave: FLOATING_SAVE_AREA,
VectorRegister: [M128A, .. 26],
VectorControl: DWORDLONG,
DebugControl: DWORDLONG,
LastBranchToRip: DWORDLONG,
LastBranchFromRip: DWORDLONG,
LastExceptionToRip: DWORDLONG,
LastExceptionFromRip: DWORDLONG,
}
#[repr(C)]
pub struct M128A {
_align_hack: [simd::u64x2, ..0], // FIXME align on 16-byte
Low: c_ulonglong,
High: c_longlong
}
#[repr(C)]
pub struct FLOATING_SAVE_AREA {
_align_hack: [simd::u64x2, ..0], // FIXME align on 16-byte
_Dummy: [u8, ..512] // FIXME: Fill this out
}
pub fn init_frame(frame: &mut super::STACKFRAME64,
ctx: &CONTEXT) -> DWORD {
frame.AddrPC.Offset = ctx.Rip as u64;
frame.AddrPC.Mode = super::AddrModeFlat;
frame.AddrStack.Offset = ctx.Rsp as u64;
frame.AddrStack.Mode = super::AddrModeFlat;
frame.AddrFrame.Offset = ctx.Rbp as u64;
frame.AddrFrame.Mode = super::AddrModeFlat;
super::IMAGE_FILE_MACHINE_AMD64
}
}
#[repr(C)]
struct Cleanup {
handle: libc::HANDLE,
SymCleanup: SymCleanupFn,
}
impl Drop for Cleanup {
fn drop(&mut self) { (self.SymCleanup)(self.handle); }
}
pub fn write(w: &mut Writer) -> IoResult<()> {
// According to windows documentation, all dbghelp functions are
// single-threaded.
static LOCK: StaticNativeMutex = NATIVE_MUTEX_INIT;
let _g = unsafe { LOCK.lock() };
// Open up dbghelp.dll, we don't link to it explicitly because it can't
// always be found. Additionally, it's nice having fewer dependencies.
let path = Path::new("dbghelp.dll");
let lib = match DynamicLibrary::open(Some(&path)) {
Ok(lib) => lib,
Err(..) => return Ok(()),
};
macro_rules! sym( ($e:expr, $t:ident) => (unsafe {
match lib.symbol($e) {
Ok(f) => mem::transmute::<*mut u8, $t>(f),
Err(..) => return Ok(())
}
}) )
// Fetch the symbols necessary from dbghelp.dll
let SymFromAddr = sym!("SymFromAddr", SymFromAddrFn);
let SymInitialize = sym!("SymInitialize", SymInitializeFn);
let SymCleanup = sym!("SymCleanup", SymCleanupFn);
let StackWalk64 = sym!("StackWalk64", StackWalk64Fn);
// Allocate necessary structures for doing the stack walk
let process = unsafe { GetCurrentProcess() };
let thread = unsafe { GetCurrentThread() };
let mut context: arch::CONTEXT = unsafe { intrinsics::init() };
unsafe { RtlCaptureContext(&mut context); }
let mut frame: STACKFRAME64 = unsafe { intrinsics::init() };
let image = arch::init_frame(&mut frame, &context);
// Initialize this process's symbols
let ret = SymInitialize(process, 0 as *mut libc::c_void, libc::TRUE);
if ret != libc::TRUE { return Ok(()) }
let _c = Cleanup { handle: process, SymCleanup: SymCleanup };
// And now that we're done with all the setup, do the stack walking!
let mut i = 0i;
try!(write!(w, "stack backtrace:\n"));
while StackWalk64(image, process, thread, &mut frame, &mut context,
0 as *mut libc::c_void,
0 as *mut libc::c_void,
0 as *mut libc::c_void,
0 as *mut libc::c_void) == libc::TRUE{
let addr = frame.AddrPC.Offset;
if addr == frame.AddrReturn.Offset || addr == 0 ||
frame.AddrReturn.Offset == 0 { break }
i += 1;
try!(write!(w, " {:2}: {:#2$x}", i, addr, super::HEX_WIDTH));
let mut info: SYMBOL_INFO = unsafe { intrinsics::init() };
info.MaxNameLen = MAX_SYM_NAME as libc::c_ulong;
// the struct size in C. the value is different to
// `size_of::<SYMBOL_INFO>() - MAX_SYM_NAME + 1` (== 81)
// due to struct alignment.
info.SizeOfStruct = 88;
let mut displacement = 0u64;
let ret = SymFromAddr(process, addr as u64, &mut displacement,
&mut info);
if ret == libc::TRUE {
try!(write!(w, " - "));
let cstr = unsafe { CString::new(info.Name.as_ptr(), false) };
let bytes = cstr.as_bytes();
match cstr.as_str() {
Some(s) => try!(super::demangle(w, s)),
None => try!(w.write(bytes[..bytes.len()-1])),
}
}
try!(w.write(['\n' as u8]));
}
Ok(())
}
}
#[cfg(test)]
mod test {
use prelude::*;
use io::MemWriter;
macro_rules! t( ($a:expr, $b:expr) => ({
let mut m = MemWriter::new();
super::demangle(&mut m, $a).unwrap();
assert_eq!(String::from_utf8(m.unwrap()).unwrap(), $b.to_string());
}) )
#[test]
fn demangle() {
t!("test", "test");
t!("_ZN4testE", "test");
t!("_ZN4test", "_ZN4test");
t!("_ZN4test1a2bcE", "test::a::bc");
}
#[test]
fn demangle_dollars() {
t!("_ZN4$UP$E", "Box");
t!("_ZN8$UP$testE", "Boxtest");
t!("_ZN8$UP$test4foobE", "Boxtest::foob");
t!("_ZN8$x20test4foobE", " test::foob");
}
#[test]
fn demangle_many_dollars() {
t!("_ZN12test$x20test4foobE", "test test::foob");
t!("_ZN12test$UP$test4foobE", "testBoxtest::foob");
}
}
Reference in New Issue View Git Blame Copy Permalink