alef 0.76.0

Opinionated polyglot binding generator for Rust libraries
Documentation 
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/// Free a byte buffer previously returned by this library via out-params.
/// `ptr`, `len`, and `cap` must match the values written by the library function,
/// or the call must pass `ptr = null` (in which case it is a no-op).
/// # Safety
/// Pointer must have been returned by this library (via out_ptr / out_len / out_cap
/// out-params), and ownership must not already have been released.
#[unsafe(no_mangle)]
pub unsafe extern "C" fn {{ prefix }}_free_bytes(ptr: *mut u8, len: usize, cap: usize) {
    catch_ffi_panic((), || {
        if ptr.is_null() {
            return;
        }
        if len != cap {
            set_last_error(1, "invalid byte buffer metadata: len and cap differ");
            return;
        }
        // SAFETY: The library returns a Box<[u8]> allocation and reports its length
        // as both len and cap; the caller contract preserves pointer and ownership.
        unsafe {
            let slice = std::ptr::slice_from_raw_parts_mut(ptr, len);
            drop(Box::<[u8]>::from_raw(slice));
        }
    })
}