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extern crate core;
extern crate libc;
use objc;
#[allow(non_camel_case_types)]
pub type objc_exception_preprocessor = unsafe extern "C" fn(objc::id) -> objc::id;
#[allow(non_camel_case_types)]
pub type objc_exception_matcher =
unsafe extern "C" fn(catch_type: objc::Class, exception: objc::id) -> libc::c_int;
#[allow(non_camel_case_types)]
pub type objc_uncaught_exception_handler = unsafe extern "C" fn(exception: objc::id);
#[allow(non_camel_case_types)]
pub type objc_exception_handler =
unsafe extern "C" fn(unused: objc::id, context: *mut libc::c_void);
#[link(name = "objc")]
extern "C" {
pub fn objc_exception_throw(exception: objc::id) -> !;
pub fn objc_exception_rethrow() -> !;
pub fn objc_begin_catch(exc_buf: *mut libc::c_void) -> objc::id;
pub fn objc_end_catch();
pub fn objc_terminate() -> !;
pub fn objc_setExceptionPreprocessor(
f: objc_exception_preprocessor,
) -> objc_exception_preprocessor;
pub fn objc_setExceptionMatcher(f: objc_exception_matcher) -> objc_exception_matcher;
pub fn objc_setUncaughtExceptionHandler(
f: objc_uncaught_exception_handler,
) -> objc_uncaught_exception_handler;
#[cfg(not(target = "ios"))]
pub fn objc_addExceptionHandler(f: objc_exception_handler, context: *mut libc::c_void) -> usize;
#[cfg(not(target = "ios"))]
pub fn objc_removeExceptionHandler(token: usize);
}
pub fn throw<T>(exception: T) -> !
where
T: Into<objc::id>,
{
unsafe { objc_exception_throw(exception.into()) };
}
extern "C" {
fn __objrs_catch_exception(
payload: *mut libc::c_void,
function: extern "C" fn(_: *mut libc::c_void),
exception: *mut objc::id,
) -> bool;
}
#[inline]
pub fn catch_exception<F: FnOnce() -> R, R>(f: F) -> Result<R, objc::id> {
#[repr(C)]
#[allow(unions_with_drop_fields)]
union FunctionAndRet<F, R> {
f: F,
ret: R,
}
extern "C" fn execute<F: FnOnce() -> R, R>(ptr: *mut libc::c_void) {
let f = unsafe { core::ptr::read(ptr as *mut F) };
let ret = f();
unsafe { core::ptr::write(ptr as *mut R, ret) };
}
let mut function_and_ret = FunctionAndRet::<F, R> { f: f };
let mut exception = unsafe { core::mem::uninitialized() };
if unsafe {
__objrs_catch_exception(
&mut function_and_ret as *mut _ as *mut libc::c_void,
execute::<F, R>,
&mut exception,
)
} {
core::mem::drop(unsafe { function_and_ret.f });
return Err(exception);
} else {
return Ok(unsafe { function_and_ret.ret });
}
}
#[macro_export]
macro_rules! catch_exception {
($($tt: tt)*) => {
$crate::catch_exception(|| { $($tt)* })
};
}
#[cfg(target_arch = "x86_64")]
global_asm!{r#"
.section __TEXT,__text,regular,pure_instructions
.globl ___objrs_catch_exception
.p2align 4, 0x90
___objrs_catch_exception: ## @__objrs_catch_exception
Lfunc_begin0:
.cfi_startproc
.cfi_personality 155, ___objc_personality_v0
.cfi_lsda 16, Lexception0
## BB#0:
pushq %rbp
Lcfi0:
.cfi_def_cfa_offset 16
pushq %rbx
Lcfi1:
.cfi_def_cfa_offset 24
pushq %rax
Lcfi2:
.cfi_def_cfa_offset 32
Lcfi3:
.cfi_offset %rbx, -24
Lcfi4:
.cfi_offset %rbp, -16
movq %rdx, %rbx
xorl %ebp, %ebp
Ltmp0:
callq *%rsi
Ltmp1:
LBB0_2:
movl %ebp, %eax
addq $8, %rsp
popq %rbx
popq %rbp
retq
LBB0_1:
Ltmp2:
movq %rax, %rdi
callq _objc_begin_catch
movq %rax, %rbp
movq %rbp, %rdi
callq _objc_retainAutorelease
movq %rbp, (%rbx)
callq _objc_end_catch
movl $1, %ebp
jmp LBB0_2
Lfunc_end0:
.cfi_endproc
.section __TEXT,__gcc_except_tab
.p2align 2
GCC_except_table0:
Lexception0:
.byte 255 ## @LPStart Encoding = omit
.byte 155 ## @TType Encoding = indirect pcrel sdata4
.asciz "\242\200\200" ## @TType base offset
.byte 3 ## Call site Encoding = udata4
.byte 26 ## Call site table length
Lset0 = Ltmp0-Lfunc_begin0 ## >> Call Site 1 <<
.long Lset0
Lset1 = Ltmp1-Ltmp0 ## Call between Ltmp0 and Ltmp1
.long Lset1
Lset2 = Ltmp2-Lfunc_begin0 ## jumps to Ltmp2
.long Lset2
.byte 1 ## On action: 1
Lset3 = Ltmp1-Lfunc_begin0 ## >> Call Site 2 <<
.long Lset3
Lset4 = Lfunc_end0-Ltmp1 ## Call between Ltmp1 and Lfunc_end0
.long Lset4
.long 0 ## has no landing pad
.byte 0 ## On action: cleanup
.byte 1 ## >> Action Record 1 <<
## Catch TypeInfo 1
.byte 0 ## No further actions
## >> Catch TypeInfos <<
.long _OBJC_EHTYPE_id@GOTPCREL+4 ## TypeInfo 1
.p2align 2
"#}
#[cfg(target_arch = "aarch64")]
global_asm!{r#"
.section __TEXT,__text,regular,pure_instructions
.globl ___objrs_catch_exception
.p2align 2
___objrs_catch_exception: ; @__objrs_catch_exception
Lfunc_begin0:
.cfi_startproc
.cfi_personality 155, ___objc_personality_v0
.cfi_lsda 16, Lexception0
; BB#0:
stp x20, x19, [sp, #-32]! ; 8-byte Folded Spill
stp x29, x30, [sp, #16] ; 8-byte Folded Spill
Lcfi0:
.cfi_def_cfa_offset 32
Lcfi1:
.cfi_offset w30, -8
Lcfi2:
.cfi_offset w29, -16
Lcfi3:
.cfi_offset w19, -24
Lcfi4:
.cfi_offset w20, -32
mov x19, x2
Ltmp0:
blr x1
Ltmp1:
; BB#1:
mov w0, #0
LBB0_2:
ldp x29, x30, [sp, #16] ; 8-byte Folded Reload
ldp x20, x19, [sp], #32 ; 8-byte Folded Reload
ret
LBB0_3:
Ltmp2:
bl _objc_begin_catch
str x0, [x19]
bl _objc_end_catch
orr w0, wzr, #0x1
b LBB0_2
Lfunc_end0:
.cfi_endproc
.section __TEXT,__gcc_except_tab
.p2align 2
GCC_except_table0:
Lexception0:
.byte 255 ; @LPStart Encoding = omit
.byte 155 ; @TType Encoding = indirect pcrel sdata4
.asciz "\242\200\200" ; @TType base offset
.byte 3 ; Call site Encoding = udata4
.byte 26 ; Call site table length
Lset0 = Ltmp0-Lfunc_begin0 ; >> Call Site 1 <<
.long Lset0
Lset1 = Ltmp1-Ltmp0 ; Call between Ltmp0 and Ltmp1
.long Lset1
Lset2 = Ltmp2-Lfunc_begin0 ; jumps to Ltmp2
.long Lset2
.byte 1 ; On action: 1
Lset3 = Ltmp1-Lfunc_begin0 ; >> Call Site 2 <<
.long Lset3
Lset4 = Lfunc_end0-Ltmp1 ; Call between Ltmp1 and Lfunc_end0
.long Lset4
.long 0 ; has no landing pad
.byte 0 ; On action: cleanup
.byte 1 ; >> Action Record 1 <<
; Catch TypeInfo 1
.byte 0 ; No further actions
; >> Catch TypeInfos <<
Ltmp3: ; TypeInfo 1
.long _OBJC_EHTYPE_id@GOT-Ltmp3
.p2align 2
"#}