sgx_trts/src/error.rs

// Copyright (c) 2017 Baidu, Inc. All Rights Reserved.
//
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use sgx_types::*;

#[link(name = "sgx_tstdc")]
extern {
    #[cfg_attr(target_os = "linux", link_name = "__errno_location")]
    fn errno_location() -> * mut c_int;

    fn strerror_r(errnum: c_int, buf: * mut c_char, buflen: size_t) -> c_int;
}

/// Get the last error number.
pub fn errno() -> i32 {
    unsafe {
        (*errno_location()) as i32
    }
}

/// Set the last error number.
pub fn set_errno(e: i32) {
    unsafe {
        *errno_location() = e as c_int
    }
}

/// Gets a detailed string description for the given error number.
pub unsafe fn error_string(errno: i32, buf: &mut [i8]) -> i32 {

    let p = buf.as_mut_ptr();
    strerror_r(errno as c_int, p as * mut c_char, buf.len()) as i32
}