Merge pull request #113 from quartiq/feature/subscription-codes

Removing arbitrary limit on subscription topic count
quartiq · Sep 19, 2022 · 65fe11b · 65fe11b
2 parents e028556 + e7e1e53
commit 65fe11b
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Showing 4 changed files with 5 additions and 22 deletions.
diff --git a/src/de/received_packet.rs b/src/de/received_packet.rs
@@ -1,7 +1,6 @@
 use crate::{
     message_types::MessageType,
     packets::{ConnAck, Disconnect, Pub, PubAck, PubComp, PubRec, SubAck},
-    reason_codes::ReasonCode,
     varint::Varint,
     ProtocolError, QoS, Retain,
 };
@@ -38,12 +37,7 @@ impl<'a> ReceivedPacket<'a> {
                     publish.payload = remaining_payload;
                 }
                 ReceivedPacket::SubAck(suback) => {
-                    for code in remaining_payload.iter().map(|&x| ReasonCode::from(x)) {
-                        suback
-                            .codes
-                            .push(code)
-                            .map_err(|_| ProtocolError::BufferSize)?;
-                    }
+                    suback.codes = remaining_payload;
                 }
                 _ => return Err(ProtocolError::MalformedPacket),
             }
@@ -222,7 +216,7 @@ mod test {
         match packet {
             ReceivedPacket::SubAck(sub_ack) => {
                 assert_eq!(sub_ack.codes.len(), 1);
-                assert_eq!(sub_ack.codes[0], ReasonCode::GrantedQos2);
+                assert_eq!(ReasonCode::from(sub_ack.codes[0]), ReasonCode::GrantedQos2);
                 assert_eq!(sub_ack.packet_identifier, 5);
             }
             _ => panic!("Invalid message"),

diff --git a/src/lib.rs b/src/lib.rs
@@ -97,9 +97,6 @@ pub const MQTT_INSECURE_DEFAULT_PORT: u16 = 1883;
 /// See [IANA Port Numbers](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.txt)
 pub const MQTT_SECURE_DEFAULT_PORT: u16 = 8883;
 
-/// The maximum number of subscriptions supported in a single request.
-pub const MAX_TOPICS_PER_SUBSCRIPTION: usize = 8;
-
 /// The quality-of-service for an MQTT message.
 #[derive(Debug, Copy, Clone, PartialEq, TryFromPrimitive, PartialOrd)]
 #[repr(u8)]
@@ -184,7 +181,6 @@ pub enum Error<E> {
     Protocol(ProtocolError),
     SessionReset,
     Clock(embedded_time::clock::Error),
-    TooManyTopics,
 }
 
 impl<E> From<embedded_time::clock::Error> for Error<E> {

diff --git a/src/mqtt_client.rs b/src/mqtt_client.rs
@@ -73,8 +73,8 @@ where
             Some(index) => self.session_state.pending_subscriptions.swap_remove(index),
         };
 
-        for code in subscribe_acknowledge.codes.iter() {
-            code.as_result()?;
+        for &code in subscribe_acknowledge.codes.iter() {
+            ReasonCode::from(code).as_result()?;
         }
 
         Ok(())
@@ -266,12 +266,6 @@ impl<
             return Err(Error::NotReady);
         }
 
-        // We can only support so many received response codes. As such, make sure that we don't
-        // allow too many concurrent topics.
-        if topics.len() > crate::MAX_TOPICS_PER_SUBSCRIPTION {
-            return Err(Error::TooManyTopics);
-        }
-
         // We can't subscribe if there's a pending write in the network.
         if self.network.has_pending_write() {
             return Err(Error::NotReady);

diff --git a/src/packets.rs b/src/packets.rs
@@ -5,7 +5,6 @@ use crate::{
     QoS, Retain,
 };
 use bit_field::BitField;
-use heapless::Vec;
 use serde::{Deserialize, Serialize};
 
 use serde::ser::SerializeStruct;
@@ -142,7 +141,7 @@ pub struct SubAck<'a> {
 
     /// The response status code of the subscription request.
     #[serde(skip)]
-    pub codes: Vec<ReasonCode, { crate::MAX_TOPICS_PER_SUBSCRIPTION }>,
+    pub codes: &'a [u8],
 }
 
 /// An MQTT PUBREC control packet