sgx_tstd/src/memchr.rs

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License..

//! Original implementation taken from rust-memchr

/// 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> {
    crate::sys::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> {
    crate::sys::memchr::memrchr(needle, haystack)
}