Function xmlDetectCharEncoding 

#[unsafe(no_mangle)]
pub const unsafe extern "C" fn xmlDetectCharEncoding(
    in_: *const c_uchar,
    len: c_int,
) -> c_int

Detect the character encoding of a buffer from its initial bytes.

UPSTREAM-PARITY

xmlCharEncoding xmlDetectCharEncoding(const unsigned char *in, int len);

SAFETY

• in_ must be valid pointers (or NULL where the upstream C contract allows), obtained from the matching constructor/owner and not yet freed; the callee may take or keep ownership exactly as the C API specifies.

The caller must not race this call with concurrent mutation of the same objects from other threads (per-object state is not internally synchronized). Violating any of the above is undefined behavior.

Exercised by the C-API differential courts (courts/suites/data-abi/*-family-probe.c) and the CLI differential courts; those pass byte-for-byte against the upstream oracle.