Implement parsing mqtt ping responses

1 files changed, 18 insertions, 0 deletions

diff --git a/mqtt_parser.c b/mqtt_parser.c
index 87e79b1..60f9674 100644
--- a/mqtt_parser.c
+++ b/mqtt_parser.c
@@ -23,9 +23,15 @@ struct SubscribeAck {
   uint8_t return_code;
 } __attribute__((packed));
 
+struct PingResp {
+  uint8_t packet_type;
+  uint8_t message_length;
+} __attribute__((packed));
+
 static_assert(sizeof(struct ConnectAck) == 4, "Unexpected connect ack size");
 static_assert(sizeof(struct SubscribeAck) == 5,
               "Unexpected subscribe ack size");
+static_assert(sizeof(struct PingResp) == 2, "Unexpected ping resp size");
 
 static enum MqttParserResult ParseConnectAck(
     const void* buffer, size_t buffer_size,
@@ -83,6 +89,16 @@ static enum MqttParserResult ParseSubscribeAck(
   return kMqttParserResultFinished;
 }
 
+static enum MqttParserResult ParsePingResp(
+    const void* buffer, size_t buffer_size,
+    const struct MqttParserCallbacks* callbacks, void* user) {
+  if (buffer_size < sizeof(struct PingResp)) return kMqttParserResultWantMore;
+  const struct PingResp* ping_resp = buffer;
+  if (ping_resp->message_length) return kMqttParserResultError;
+  callbacks->on_finished(user, sizeof(struct PingResp));
+  return kMqttParserResultFinished;
+}
+
 enum MqttParserResult MqttParserParse(
     const void* buffer, size_t buffer_size,
     const struct MqttParserCallbacks* callbacks, void* user) {
@@ -96,6 +112,8 @@ enum MqttParserResult MqttParserParse(
       return ParsePublish(buffer, buffer_size, callbacks, user);
     case 0x90:
       return ParseSubscribeAck(buffer, buffer_size, callbacks, user);
+    case 0xd0:
+      return ParsePingResp(buffer, buffer_size, callbacks, user);
     default:
       return kMqttParserResultError;
   }