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#![allow(private_no_mangle_fns)]
use core::any::Any;
use core::ptr;
use alloc::boxed::Box;
use unwind as uw;
use libc::{c_int, uintptr_t};
use dwarf::eh::{self, EHContext, EHAction};
#[repr(C)]
struct Exception {
_uwe: uw::_Unwind_Exception,
cause: Option<Box<Any + Send>>,
}
pub unsafe fn panic(data: Box<Any + Send>) -> u32 {
let exception = Box::new(Exception {
_uwe: uw::_Unwind_Exception {
exception_class: rust_exception_class(),
exception_cleanup: exception_cleanup,
private: [0; uw::unwinder_private_data_size],
},
cause: Some(data),
});
let exception_param = Box::into_raw(exception) as *mut uw::_Unwind_Exception;
return uw::_Unwind_RaiseException(exception_param) as u32;
extern "C" fn exception_cleanup(_unwind_code: uw::_Unwind_Reason_Code,
exception: *mut uw::_Unwind_Exception) {
unsafe {
let _: Box<Exception> = Box::from_raw(exception as *mut Exception);
}
}
}
pub fn payload() -> *mut u8 {
ptr::null_mut()
}
pub unsafe fn cleanup(ptr: *mut u8) -> Box<Any + Send> {
let my_ep = ptr as *mut Exception;
let cause = (*my_ep).cause.take();
uw::_Unwind_DeleteException(ptr as *mut _);
cause.unwrap()
}
fn rust_exception_class() -> uw::_Unwind_Exception_Class {
0x4d4f5a_00_52555354
}
#[cfg(target_arch = "x86")]
const UNWIND_DATA_REG: (i32, i32) = (0, 2);
#[cfg(target_arch = "x86_64")]
const UNWIND_DATA_REG: (i32, i32) = (0, 1);
#[cfg(any(target_arch = "arm", target_arch = "aarch64"))]
const UNWIND_DATA_REG: (i32, i32) = (0, 1);
#[cfg(any(target_arch = "mips", target_arch = "mips64"))]
const UNWIND_DATA_REG: (i32, i32) = (4, 5);
#[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))]
const UNWIND_DATA_REG: (i32, i32) = (3, 4);
#[cfg(target_arch = "s390x")]
const UNWIND_DATA_REG: (i32, i32) = (6, 7);
#[cfg(target_arch = "sparc64")]
const UNWIND_DATA_REG: (i32, i32) = (24, 25);
#[cfg(all(any(target_os = "ios", not(target_arch = "arm"))))]
#[lang = "eh_personality"]
#[no_mangle]
#[allow(unused)]
unsafe extern "C" fn rust_eh_personality(version: c_int,
actions: uw::_Unwind_Action,
exception_class: uw::_Unwind_Exception_Class,
exception_object: *mut uw::_Unwind_Exception,
context: *mut uw::_Unwind_Context)
-> uw::_Unwind_Reason_Code {
if version != 1 {
return uw::_URC_FATAL_PHASE1_ERROR;
}
let eh_action = find_eh_action(context);
if actions as i32 & uw::_UA_SEARCH_PHASE as i32 != 0 {
match eh_action {
EHAction::None |
EHAction::Cleanup(_) => return uw::_URC_CONTINUE_UNWIND,
EHAction::Catch(_) => return uw::_URC_HANDLER_FOUND,
EHAction::Terminate => return uw::_URC_FATAL_PHASE1_ERROR,
}
} else {
match eh_action {
EHAction::None => return uw::_URC_CONTINUE_UNWIND,
EHAction::Cleanup(lpad) |
EHAction::Catch(lpad) => {
uw::_Unwind_SetGR(context, UNWIND_DATA_REG.0, exception_object as uintptr_t);
uw::_Unwind_SetGR(context, UNWIND_DATA_REG.1, 0);
uw::_Unwind_SetIP(context, lpad);
return uw::_URC_INSTALL_CONTEXT;
}
EHAction::Terminate => return uw::_URC_FATAL_PHASE2_ERROR,
}
}
}
#[cfg(all(target_arch = "arm", not(target_os = "ios")))]
#[lang = "eh_personality"]
#[no_mangle]
unsafe extern "C" fn rust_eh_personality(state: uw::_Unwind_State,
exception_object: *mut uw::_Unwind_Exception,
context: *mut uw::_Unwind_Context)
-> uw::_Unwind_Reason_Code {
let state = state as c_int;
let action = state & uw::_US_ACTION_MASK as c_int;
let search_phase = if action == uw::_US_VIRTUAL_UNWIND_FRAME as c_int {
if state & uw::_US_FORCE_UNWIND as c_int != 0 {
return continue_unwind(exception_object, context);
}
true
} else if action == uw::_US_UNWIND_FRAME_STARTING as c_int {
false
} else if action == uw::_US_UNWIND_FRAME_RESUME as c_int {
return continue_unwind(exception_object, context);
} else {
return uw::_URC_FAILURE;
};
uw::_Unwind_SetGR(context,
uw::UNWIND_POINTER_REG,
exception_object as uw::_Unwind_Ptr);
let eh_action = find_eh_action(context);
if search_phase {
match eh_action {
EHAction::None |
EHAction::Cleanup(_) => return continue_unwind(exception_object, context),
EHAction::Catch(_) => return uw::_URC_HANDLER_FOUND,
EHAction::Terminate => return uw::_URC_FAILURE,
}
} else {
match eh_action {
EHAction::None => return continue_unwind(exception_object, context),
EHAction::Cleanup(lpad) |
EHAction::Catch(lpad) => {
uw::_Unwind_SetGR(context, UNWIND_DATA_REG.0, exception_object as uintptr_t);
uw::_Unwind_SetGR(context, UNWIND_DATA_REG.1, 0);
uw::_Unwind_SetIP(context, lpad);
return uw::_URC_INSTALL_CONTEXT;
}
EHAction::Terminate => return uw::_URC_FAILURE,
}
}
unsafe fn continue_unwind(exception_object: *mut uw::_Unwind_Exception,
context: *mut uw::_Unwind_Context)
-> uw::_Unwind_Reason_Code {
if __gnu_unwind_frame(exception_object, context) == uw::_URC_NO_REASON {
uw::_URC_CONTINUE_UNWIND
} else {
uw::_URC_FAILURE
}
}
extern "C" {
fn __gnu_unwind_frame(exception_object: *mut uw::_Unwind_Exception,
context: *mut uw::_Unwind_Context)
-> uw::_Unwind_Reason_Code;
}
}
unsafe fn find_eh_action(context: *mut uw::_Unwind_Context) -> EHAction {
let lsda = uw::_Unwind_GetLanguageSpecificData(context) as *const u8;
let mut ip_before_instr: c_int = 0;
let ip = uw::_Unwind_GetIPInfo(context, &mut ip_before_instr);
let eh_context = EHContext {
ip: if ip_before_instr != 0 { ip } else { ip - 1 },
func_start: uw::_Unwind_GetRegionStart(context),
get_text_start: &|| uw::_Unwind_GetTextRelBase(context),
get_data_start: &|| uw::_Unwind_GetDataRelBase(context),
};
eh::find_eh_action(lsda, &eh_context)
}
#[cfg(all(target_os="windows", target_arch = "x86", target_env="gnu"))]
#[lang = "eh_unwind_resume"]
#[unwind]
unsafe extern "C" fn rust_eh_unwind_resume(panic_ctx: *mut u8) -> ! {
uw::_Unwind_Resume(panic_ctx as *mut uw::_Unwind_Exception);
}
#[cfg(all(target_os="windows", target_arch = "x86", target_env="gnu"))]
pub mod eh_frame_registry {
extern "C" {
fn __register_frame_info(eh_frame_begin: *const u8, object: *mut u8);
fn __deregister_frame_info(eh_frame_begin: *const u8, object: *mut u8);
}
#[no_mangle]
pub unsafe extern "C" fn rust_eh_register_frames(eh_frame_begin: *const u8, object: *mut u8) {
__register_frame_info(eh_frame_begin, object);
}
#[no_mangle]
pub unsafe extern "C" fn rust_eh_unregister_frames(eh_frame_begin: *const u8,
object: *mut u8) {
__deregister_frame_info(eh_frame_begin, object);
}
}