Start of Kobj support: Semaphores and Threads

zephyr-sys/build.rs

@@ -71,6 +71,7 @@ fn main() -> Result<()> {
         .allowlist_function("k_.*")
         .allowlist_function("gpio_.*")
         .allowlist_function("sys_.*")
+        .allowlist_item("E.*")
         // Deprecated
         .blocklist_function("sys_clock_timeout_end_calc")
         .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))

zephyr/src/error.rs

@@ -0,0 +1,56 @@
+// Copyright (c) 2024 Linaro LTD
+// SPDX-License-Identifier: Apache-2.0
+
+//! # Zephyr errors
+//!
+//! This module contains an `Error` and `Result` type for use in wrapped Zephyr calls.  Many
+//! operations in Zephyr return an int result where negative values correspond with errnos.
+//! Convert those to a `Result` type where the `Error` condition maps to errnos.
+//!
+//! Initially, this will just simply wrap the numeric error code, but it might make sense to make
+//! this an enum itself, however, it would probably be better to auto-generate this enum instead of
+//! trying to maintain the list manually.
+
+use core::ffi::c_int;
+use core::fmt;
+
+// This is a little messy because the constants end up as u32 from bindgen, although the values are
+// negative.
+
+/// A Zephyr error.
+///
+/// Represents an error result returned within Zephyr.
+pub struct Error(pub u32);
+
+impl core::error::Error for Error {}
+
+impl fmt::Display for Error {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "zephyr error errno:{}", self.0)
+    }
+}
+
+impl fmt::Debug for Error {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "zephyr error errno:{}", self.0)
+    }
+}
+
+/// Wraps a value with a possible Zephyr error.
+pub type Result<T> = core::result::Result<T, Error>;
+
+/// Map a return result from Zephyr into an Result.
+///
+/// Negative return results being considered errors.
+pub fn to_result(code: c_int) -> Result<c_int> {
+    if code < 0 {
+        Err(Error(-code as u32))
+    } else {
+        Ok(code)
+    }
+}
+
+/// Map a return result, with a void result.
+pub fn to_result_void(code: c_int) -> Result<()> {
+    to_result(code).map(|_| ())
+}

zephyr/src/lib.rs

@@ -10,9 +10,12 @@
 #![allow(unexpected_cfgs)]
 #![deny(missing_docs)]
 
+pub mod error;
 pub mod sys;
 pub mod time;
 
+pub use error::{Error, Result};
+
 // Bring in the generated kconfig module
 pub mod kconfig {
     //! Zephyr Kconfig values.