sgx_tstd/src/memchr.rs

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//! Original implementation taken from rust-memchr
use sgx_trts;

/// A safe interface to `memchr`.
///
/// Returns the index corresponding to the first occurrence of `needle` in
/// `haystack`, or `None` if one is not found.
///
/// memchr reduces to super-optimized machine code at around an order of
/// magnitude faster than `haystack.iter().position(|&b| b == needle)`.
/// (See benchmarks.)
///
#[inline]
pub fn memchr(needle: u8, haystack: &[u8]) -> Option<usize> {
    sgx_trts::memchr::memchr(needle, haystack)
}

/// A safe interface to `memrchr`.
///
/// Returns the index corresponding to the last occurrence of `needle` in
/// `haystack`, or `None` if one is not found.
///
#[inline]
pub fn memrchr(needle: u8, haystack: &[u8]) -> Option<usize> {
    sgx_trts::memchr::memrchr(needle, haystack)
}