60 lines
1.2 KiB
Rust
60 lines
1.2 KiB
Rust
/*
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Module: unsafe
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Unsafe operations
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*/
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export reinterpret_cast, leak;
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#[abi = "rust-intrinsic"]
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native mod rusti {
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fn cast<T, U>(src: T) -> U;
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}
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#[abi = "cdecl"]
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native mod rustrt {
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fn leak<T>(-thing: T);
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}
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/*
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Function: reinterpret_cast
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Casts the value at `src` to U. The two types must have the same length.
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*/
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unsafe fn reinterpret_cast<T, U>(src: T) -> U {
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let t1 = sys::get_type_desc::<T>();
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let t2 = sys::get_type_desc::<U>();
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if (*t1).size != (*t2).size {
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fail "attempt to cast values of differing sizes";
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}
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ret rusti::cast(src);
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}
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/*
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Function: leak
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Move `thing` into the void.
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The leak function will take ownership of the provided value but neglect
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to run any required cleanup or memory-management operations on it. This
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can be used for various acts of magick, particularly when using
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reinterpret_cast on managed pointer types.
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*/
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unsafe fn leak<T>(-thing: T) { rustrt::leak(thing); }
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#[cfg(test)]
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mod tests {
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#[test]
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fn test_reinterpret_cast() unsafe {
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assert reinterpret_cast(1) == 1u;
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}
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#[test]
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#[should_fail]
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#[ignore(cfg(target_os = "win32"))]
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fn test_reinterpret_cast_wrong_size() unsafe {
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let _i: uint = reinterpret_cast(0u8);
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}
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}
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