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/*
Module: ptr
Unsafe pointer utility functions
*/
#[abi = "rust-intrinsic"]
native mod rusti {
fn addr_of<T>(val: T) -> *T;
fn ptr_offset<T>(ptr: *T, count: ctypes::uintptr_t) -> *T;
}
/*
Function: addr_of
Get an unsafe pointer to a value
*/
fn addr_of<T>(val: T) -> *T { ret rusti::addr_of(val); }
/*
Function: mut_addr_of
Get an unsafe mutable pointer to a value
*/
fn mut_addr_of<T>(val: T) -> *mutable T unsafe {
ret unsafe::reinterpret_cast(rusti::addr_of(val));
}
/*
Function: offset
Calculate the offset from a pointer
*/
fn offset<T>(ptr: *T, count: uint) -> *T {
ret rusti::ptr_offset(ptr, count);
}
/*
Function: mut_offset
Calculate the offset from a mutable pointer
*/
fn mut_offset<T>(ptr: *mutable T, count: uint) -> *mutable T {
ret rusti::ptr_offset(ptr as *T, count) as *mutable T;
}
/*
Function: null
Create an unsafe null pointer
*/
fn null<T>() -> *T unsafe { ret unsafe::reinterpret_cast(0u); }
#[test]
fn test() unsafe {
type pair = {mutable fst: int, mutable snd: int};
let p = {mutable fst: 10, mutable snd: 20};
let pptr: *mutable pair = mut_addr_of(p);
let iptr: *mutable int = unsafe::reinterpret_cast(pptr);
assert (*iptr == 10);;
*iptr = 30;
assert (*iptr == 30);
assert (p.fst == 30);;
*pptr = {mutable fst: 50, mutable snd: 60};
assert (*iptr == 50);
assert (p.fst == 50);
assert (p.snd == 60);
}
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