[eclipse-iceoryx#547] C binding for attribute

iceoryx2-ffi/ffi/src/api/attribute.rs

@@ -0,0 +1,153 @@
+// Copyright (c) 2024 Contributors to the Eclipse Foundation
+//
+// See the NOTICE file(s) distributed with this work for additional
+// information regarding copyright ownership.
+//
+// This program and the accompanying materials are made available under the
+// terms of the Apache Software License 2.0 which is available at
+// https://www.apache.org/licenses/LICENSE-2.0, or the MIT license
+// which is available at https://opensource.org/licenses/MIT.
+//
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+#![allow(non_camel_case_types)]
+
+use crate::api::{
+    iox2_callback_context, iox2_event_id_t, iox2_service_type_e, iox2_unique_listener_id_h,
+    iox2_unique_listener_id_t, AssertNonNullHandle, HandleToType, IOX2_OK,
+};
+use crate::iox2_file_descriptor_ptr;
+
+use iceoryx2::service::attribute::Attribute;
+use iceoryx2_bb_elementary::static_assert::*;
+use iceoryx2_bb_posix::file_descriptor::FileDescriptor;
+use iceoryx2_ffi_macros::iceoryx2_ffi;
+
+use core::ffi::{c_char, c_int};
+use core::mem::ManuallyDrop;
+use core::time::Duration;
+
+// BEGIN types definition
+
+#[repr(C)]
+#[repr(align(8))] // alignment of Attribute
+pub struct iox2_attribute_storage_t {
+    internal: [u8; 1656], // magic number obtained with size_of::<Attribute>()
+}
+
+#[repr(C)]
+#[iceoryx2_ffi(Attribute)]
+pub struct iox2_attribute_t {
+    value: iox2_attribute_storage_t,
+    deleter: fn(*mut iox2_attribute_t),
+}
+
+impl iox2_attribute_t {
+    pub(super) fn init(&mut self, value: Attribute, deleter: fn(*mut iox2_attribute_t)) {
+        self.value.init(value);
+        self.deleter = deleter;
+    }
+}
+
+pub struct iox2_attribute_h_t;
+/// The owning handle for `iox2_listener_t`. Passing the handle to an function transfers the ownership.
+pub type iox2_attribute_h = *mut iox2_attribute_h_t;
+/// The non-owning handle for `iox2_listener_t`. Passing the handle to an function does not transfers the ownership.
+pub type iox2_attribute_h_ref = *const iox2_attribute_h;
+
+impl AssertNonNullHandle for iox2_attribute_h {
+    fn assert_non_null(self) {
+        debug_assert!(!self.is_null());
+    }
+}
+
+impl AssertNonNullHandle for iox2_attribute_h_ref {
+    fn assert_non_null(self) {
+        debug_assert!(!self.is_null());
+        unsafe {
+            debug_assert!(!(*self).is_null());
+        }
+    }
+}
+
+impl HandleToType for iox2_attribute_h {
+    type Target = *mut iox2_attribute_t;
+
+    fn as_type(self) -> Self::Target {
+        self as *mut _ as _
+    }
+}
+
+impl HandleToType for iox2_attribute_h_ref {
+    type Target = *mut iox2_attribute_t;
+
+    fn as_type(self) -> Self::Target {
+        unsafe { *self as *mut _ as _ }
+    }
+}
+// END type definition
+
+// BEGIN C API
+#[no_mangle]
+pub unsafe extern "C" fn iox2_attribute_drop(handle: iox2_attribute_h) {
+    handle.assert_non_null();
+
+    let attribute = &mut *handle.as_type();
+
+    core::ptr::drop_in_place(attribute.value.as_mut());
+    (attribute.deleter)(attribute);
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn iox2_attribute_key_len(handle: iox2_attribute_h_ref) -> usize {
+    handle.assert_non_null();
+
+    let attribute = &mut *handle.as_type();
+    attribute.value.as_ref().key().len()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn iox2_attribute_key(
+    handle: iox2_attribute_h_ref,
+    buffer: *mut c_char,
+    buffer_len: usize,
+) -> usize {
+    handle.assert_non_null();
+
+    let attribute = &mut *handle.as_type();
+    let copied_key_length = buffer_len.min(attribute.value.as_ref().key().len());
+    core::ptr::copy_nonoverlapping(
+        attribute.value.as_ref().key().as_ptr(),
+        buffer.cast(),
+        copied_key_length,
+    );
+    copied_key_length
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn iox2_attribute_value_len(handle: iox2_attribute_h_ref) -> usize {
+    handle.assert_non_null();
+
+    let attribute = &mut *handle.as_type();
+    attribute.value.as_ref().value().len()
+}
+
+#[no_mangle]
+pub unsafe extern "C" fn iox2_attribute_value(
+    handle: iox2_attribute_h_ref,
+    buffer: *mut c_char,
+    buffer_len: usize,
+) -> usize {
+    handle.assert_non_null();
+
+    let attribute = &mut *handle.as_type();
+    let copied_key_length = buffer_len.min(attribute.value.as_ref().value().len());
+    core::ptr::copy_nonoverlapping(
+        attribute.value.as_ref().key().as_ptr(),
+        buffer.cast(),
+        copied_key_length,
+    );
+    copied_key_length
+}
+
+// END C API

iceoryx2-ffi/ffi/src/api/mod.rs

@@ -19,6 +19,7 @@ use iceoryx2_bb_elementary::AsStringLiteral;
 
 use core::ffi::{c_char, c_int, c_void};
 
+mod attribute;
 mod config;
 mod event_id;
 mod file_descriptor;
@@ -60,6 +61,7 @@ mod waitset_attachment_id;
 mod waitset_builder;
 mod waitset_guard;
 
+pub use attribute::*;
 pub use config::*;
 pub use event_id::*;
 pub use file_descriptor::*;