protobuf/rust/shared.rs

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//! Kernel-agnostic logic for the Rust Protobuf Runtime.
//!
//! For kernel-specific logic this crate delegates to the respective __runtime
//! crate.

#[cfg(cpp_kernel)]
pub extern crate cpp as __runtime;
#[cfg(upb_kernel)]
pub extern crate upb as __runtime;

pub use __runtime::SerializedData;

use std::fmt;
use std::slice;

/// Represents error during deserialization.
#[derive(Debug, Clone)]
pub struct ParseError;

impl fmt::Display for ParseError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "Couldn't deserialize given bytes into a proto")
    }
}

/// Represents an ABI-stable version of &[u8]/string_view (a borrowed slice of
/// bytes) for FFI use only.
#[repr(C)]
#[derive(Copy, Clone)]
pub struct PtrAndLen {
    /// Borrows the memory.
    pub ptr: *const u8,
    pub len: usize,
}

impl PtrAndLen {
    pub unsafe fn as_ref<'a>(self) -> &'a [u8] {
        slice::from_raw_parts(self.ptr, self.len)
    }
}