| @@ -83,6 +83,27 @@ use crate::ub_checks; |
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/// } |
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/// ``` |
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/// |
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+/// ### FFI: Handling null pointers |
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+/// |
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+/// In languages such as C++, pointers to empty collections are not guaranteed to be non-null. |
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+/// When accepting such pointers, they have to be checked for null-ness to avoid undefined |
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+/// behavior. |
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+/// |
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+/// ``` |
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+/// use std::slice; |
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+/// |
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+/// unsafe extern "C" fn handle_slice(ptr: *const f32, len: usize) { |
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+/// let data = if ptr.is_null() { |
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+/// // `len` is assumed to be 0. |
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+/// &[] |
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+/// } else { |
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+/// unsafe { slice::from_raw_parts(ptr, len) } |
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+/// }; |
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+/// dbg!(data); |
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+/// // ... |
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+/// } |
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+/// ``` |
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+/// |
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/// [valid]: ptr#safety |
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/// [`NonNull::dangling()`]: ptr::NonNull::dangling |
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#[inline] |