diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/mod.rs | 110 | ||||
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/printing/dladdr.rs | 35 | ||||
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/printing/mod.rs | 33 | ||||
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/tracing/backtrace_fn.rs | 39 | ||||
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/tracing/gcc_s.rs | 99 | ||||
| -rw-r--r-- | src/libstd/sys/vxworks/backtrace/tracing/mod.rs | 8 |
6 files changed, 0 insertions, 324 deletions
diff --git a/src/libstd/sys/vxworks/backtrace/mod.rs b/src/libstd/sys/vxworks/backtrace/mod.rs deleted file mode 100644 index 0887e5a4df9..00000000000 --- a/src/libstd/sys/vxworks/backtrace/mod.rs +++ /dev/null @@ -1,110 +0,0 @@ -/// 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 macOS, 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 thread -/// 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 macOS. It appears dladdr() -/// uses magic to consult the local symbol table, or we're putting everything -/// in the dynamic symbol table anyway. Regardless, for macOS, 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 macOS, 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. - -pub use self::tracing::unwind_backtrace; -pub use self::printing::{foreach_symbol_fileline, resolve_symname}; - -// tracing impls: -mod tracing; -// symbol resolvers: -mod printing; - -#[cfg(not(target_os = "emscripten"))] -pub mod gnu { - use crate::io; - use crate::fs; - - use libc::c_char; - - #[cfg(not(any(target_os = "macos", target_os = "ios")))] - pub fn get_executable_filename() -> io::Result<(Vec<c_char>, fs::File)> { - Err(io::Error::new(io::ErrorKind::Other, "Not implemented")) - } - - #[cfg(any(target_os = "macos", target_os = "ios"))] - pub fn get_executable_filename() -> io::Result<(Vec<c_char>, fs::File)> { - use crate::env; - use crate::os::unix::ffi::OsStrExt; - - let filename = env::current_exe()?; - let file = fs::File::open(&filename)?; - let mut filename_cstr: Vec<_> = filename.as_os_str().as_bytes().iter() - .map(|&x| x as c_char).collect(); - filename_cstr.push(0); // Null terminate - Ok((filename_cstr, file)) - } -} - -pub struct BacktraceContext; diff --git a/src/libstd/sys/vxworks/backtrace/printing/dladdr.rs b/src/libstd/sys/vxworks/backtrace/printing/dladdr.rs deleted file mode 100644 index 202164dd3c4..00000000000 --- a/src/libstd/sys/vxworks/backtrace/printing/dladdr.rs +++ /dev/null @@ -1,35 +0,0 @@ -use crate::io; -use crate::intrinsics; -use crate::ffi::CStr; -use crate::sys::backtrace::BacktraceContext; -use crate::sys_common::backtrace::Frame; - -pub fn resolve_symname<F>(frame: Frame, - callback: F, - _: &BacktraceContext) -> io::Result<()> - where F: FnOnce(Option<&str>) -> io::Result<()> -{ - unsafe { - let mut info: Dl_info = intrinsics::init(); - let symname = if dladdr(frame.exact_position as *mut _, &mut info) == 0 || - info.dli_sname.is_null() { - None - } else { - CStr::from_ptr(info.dli_sname).to_str().ok() - }; - callback(symname) - } -} - -#[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 { - #[ link_name = "_rtld_dladdr" ] - fn dladdr(addr: *const libc::c_void, info: *mut Dl_info) -> libc::c_int; -} diff --git a/src/libstd/sys/vxworks/backtrace/printing/mod.rs b/src/libstd/sys/vxworks/backtrace/printing/mod.rs deleted file mode 100644 index d090caede43..00000000000 --- a/src/libstd/sys/vxworks/backtrace/printing/mod.rs +++ /dev/null @@ -1,33 +0,0 @@ -mod dladdr; - -use crate::sys::backtrace::BacktraceContext; -use crate::sys_common::backtrace::Frame; -use crate::io; - -#[cfg(target_os = "emscripten")] -pub use self::dladdr::resolve_symname; - -#[cfg(target_os = "emscripten")] -pub fn foreach_symbol_fileline<F>(_: Frame, _: F, _: &BacktraceContext) -> io::Result<bool> -where - F: FnMut(&[u8], u32) -> io::Result<()> -{ - Ok(false) -} - -#[cfg(not(target_os = "emscripten"))] -pub use crate::sys_common::gnu::libbacktrace::foreach_symbol_fileline; - -#[cfg(not(target_os = "emscripten"))] -pub fn resolve_symname<F>(frame: Frame, callback: F, bc: &BacktraceContext) -> io::Result<()> -where - F: FnOnce(Option<&str>) -> io::Result<()> -{ - crate::sys_common::gnu::libbacktrace::resolve_symname(frame, |symname| { - if symname.is_some() { - callback(symname) - } else { - dladdr::resolve_symname(frame, callback, bc) - } - }, bc) -} diff --git a/src/libstd/sys/vxworks/backtrace/tracing/backtrace_fn.rs b/src/libstd/sys/vxworks/backtrace/tracing/backtrace_fn.rs deleted file mode 100644 index a628d107ad6..00000000000 --- a/src/libstd/sys/vxworks/backtrace/tracing/backtrace_fn.rs +++ /dev/null @@ -1,39 +0,0 @@ -/// 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 crate::io; -use crate::ptr; -use crate::sys::backtrace::BacktraceContext; -use crate::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, - inline_context: 0, - }; - } - Ok((nb_frames as usize, BacktraceContext)) -} - -extern { - fn backtrace(buf: *mut *mut libc::c_void, sz: libc::c_int) -> libc::c_int; -} diff --git a/src/libstd/sys/vxworks/backtrace/tracing/gcc_s.rs b/src/libstd/sys/vxworks/backtrace/tracing/gcc_s.rs deleted file mode 100644 index e6379132baf..00000000000 --- a/src/libstd/sys/vxworks/backtrace/tracing/gcc_s.rs +++ /dev/null @@ -1,99 +0,0 @@ -use crate::error::Error; -use crate::fmt; -use crate::io; -use crate::sys::backtrace::BacktraceContext; -use crate::sys_common::backtrace::Frame; - -use unwind as uw; - -struct Context<'a> { - idx: usize, - frames: &'a mut [Frame], -} - -#[derive(Debug)] -struct UnwindError(uw::_Unwind_Reason_Code); - -impl Error for UnwindError { - fn description(&self) -> &'static str { - "unexpected return value while unwinding" - } -} - -impl fmt::Display for UnwindError { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(f, "{}: {:?}", self.description(), self.0) - } -} - -#[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)> -{ - let mut cx = Context { - idx: 0, - frames, - }; - let result_unwind = unsafe { - uw::_Unwind_Backtrace(trace_fn, - &mut cx as *mut Context<'_> - as *mut libc::c_void) - }; - // See libunwind:src/unwind/Backtrace.c for the return values. - // No, there is no doc. - match result_unwind { - // These return codes seem to be benign and need to be ignored for backtraces - // to show up properly on all tested platforms. - uw::_URC_END_OF_STACK | uw::_URC_FATAL_PHASE1_ERROR | uw::_URC_FAILURE => { - Ok((cx.idx, BacktraceContext)) - } - _ => { - Err(io::Error::new(io::ErrorKind::Other, - UnwindError(result_unwind))) - } - } -} - -extern fn trace_fn(ctx: *mut uw::_Unwind_Context, - arg: *mut libc::c_void) -> uw::_Unwind_Reason_Code { - let cx = unsafe { &mut *(arg as *mut Context<'_>) }; - if cx.idx >= cx.frames.len() { - return uw::_URC_NORMAL_STOP; - } - - 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 { - // this is a non-signaling frame, so `ip` refers to the address - // after the calling instruction. account for that. - ip = (ip as usize - 1) as *mut _; - } - - // 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 panic 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 symaddr = if cfg!(target_os = "macos") || cfg!(target_os = "ios") { - ip - } else { - unsafe { uw::_Unwind_FindEnclosingFunction(ip) } - }; - - cx.frames[cx.idx] = Frame { - symbol_addr: symaddr as *mut u8, - exact_position: ip as *mut u8, - inline_context: 0, - }; - cx.idx += 1; - - uw::_URC_NO_REASON -} diff --git a/src/libstd/sys/vxworks/backtrace/tracing/mod.rs b/src/libstd/sys/vxworks/backtrace/tracing/mod.rs deleted file mode 100644 index 11863e64545..00000000000 --- a/src/libstd/sys/vxworks/backtrace/tracing/mod.rs +++ /dev/null @@ -1,8 +0,0 @@ -pub use self::imp::*; - -#[cfg(not(all(target_os = "ios", target_arch = "arm")))] -#[path = "gcc_s.rs"] -mod imp; -#[cfg(all(target_os = "ios", target_arch = "arm"))] -#[path = "backtrace_fn.rs"] -mod imp; |