Merge pull request #46 from smaeul/up/no-sync

Fall back to Rc on targets without atomics

Author: redboltz

src/mqtt/common/arc.rs

@@ -0,0 +1,26 @@
+// MIT License
+//
+// Copyright (c) 2025 Takatoshi Kondo
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#[cfg(target_has_atomic = "ptr")]
+pub type Arc<T> = alloc::sync::Arc<T>;
+#[cfg(not(target_has_atomic = "ptr"))]
+pub type Arc<T> = alloc::rc::Rc<T>;

src/mqtt/common/arc_payload.rs

@@ -20,7 +20,8 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-use alloc::{string::String, sync::Arc, vec::Vec};
+use crate::mqtt::Arc;
+use alloc::{string::String, vec::Vec};
 use serde::{Serialize, Serializer};
 
 // SSO buffer size configuration - priority-based selection for maximum size

src/mqtt/common/mod.rs

@@ -19,6 +19,10 @@
 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
+
+mod arc;
+pub use arc::Arc;
+
 mod arc_payload;
 pub use arc_payload::{ArcPayload, IntoPayload};
 

src/mqtt/connection/packet_builder.rs

@@ -19,9 +19,10 @@
 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
-use crate::mqtt::common::Cursor;
+
+use crate::mqtt::common::{Arc, Cursor};
 use crate::mqtt::result_code::MqttError;
-use alloc::{sync::Arc, vec::Vec};
+use alloc::vec::Vec;
 
 #[derive(Debug, Clone)]
 pub enum PacketData {

src/mqtt/mod.rs

@@ -30,6 +30,6 @@ pub use connection::SendBehavior;
 pub use connection::Version;
 
 pub mod common;
-pub use common::{ArcPayload, IntoPayload, ValueAllocator};
+pub use common::{Arc, ArcPayload, IntoPayload, ValueAllocator};
 
 pub mod result_code;

src/mqtt/packet/v3_1_1/publish.rs

@@ -20,7 +20,6 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-use alloc::sync::Arc;
 use alloc::vec::Vec;
 use core::fmt;
 use core::mem;
@@ -42,7 +41,7 @@ use crate::mqtt::packet::GenericPacketDisplay;
 use crate::mqtt::packet::GenericPacketTrait;
 use crate::mqtt::packet::IsPacketId;
 use crate::mqtt::result_code::MqttError;
-use crate::mqtt::{ArcPayload, IntoPayload};
+use crate::mqtt::{Arc, ArcPayload, IntoPayload};
 
 /// MQTT 3.1.1 PUBLISH packet representation
 ///

src/mqtt/packet/v5_0/publish.rs

@@ -21,7 +21,6 @@
 // SOFTWARE.
 
 use alloc::string::String;
-use alloc::sync::Arc;
 use alloc::vec::Vec;
 use core::fmt;
 use core::mem;
@@ -48,7 +47,7 @@ use crate::mqtt::packet::IsPacketId;
 use crate::mqtt::packet::PropertiesToBuffers;
 use crate::mqtt::packet::{Properties, PropertiesParse, PropertiesSize, Property};
 use crate::mqtt::result_code::MqttError;
-use crate::mqtt::{ArcPayload, IntoPayload};
+use crate::mqtt::{Arc, ArcPayload, IntoPayload};
 
 /// MQTT 5.0 PUBLISH packet representation
 ///