ExchangeContext remove unused flags (#17731)

* ExchangeContext remove unused flags

* Update src/messaging/ReliableMessageContext.h

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

* Resolve comments: do not rename HasPiggybackAckPending

* Update comments

Co-authored-by: Boris Zbarsky <bzbarsky@apple.com>

Author: 2 people

src/messaging/ExchangeContext.cpp

@@ -302,7 +302,6 @@ ExchangeContext::ExchangeContext(ExchangeManager * em, uint16_t ExchangeId, cons
     mFlags.Set(Flags::kFlagInitiator, Initiator);
     mDelegate = delegate;
 
-    SetDropAckDebug(false);
     SetAckPending(false);
 
     // Do not request Ack for multicast

src/messaging/ReliableMessageContext.cpp

@@ -103,10 +103,6 @@ void ReliableMessageContext::HandleRcvdAck(uint32_t ackMessageCounter)
 CHIP_ERROR ReliableMessageContext::HandleNeedsAck(uint32_t messageCounter, BitFlags<MessageFlagValues> messageFlags)
 
 {
-    // Skip processing ack if drop ack debug is enabled.
-    if (ShouldDropAckDebug())
-        return CHIP_NO_ERROR;
-
     CHIP_ERROR err = HandleNeedsAckInner(messageCounter, messageFlags);
 
     // Schedule next physical wakeup on function exit

src/messaging/ReliableMessageContext.h

@@ -67,9 +67,9 @@ class ReliableMessageContext
     }
 
     /**
-     * Check whether we have an ack to piggyback on the message we are sending.
-     * If true, TakePendingPeerAckMessageCounter will return a valid value that
-     * should be included as an ack in the message.
+     * Check whether we have a mPendingPeerAckMessageCounter. The counter is
+     * valid once we receive a message which requests an ack. Once
+     * mPendingPeerAckMessageCounter is valid, it never stops being valid.
      */
     bool HasPiggybackAckPending() const;
 
@@ -102,26 +102,6 @@ class ReliableMessageContext
      */
     void SetAutoRequestAck(bool autoReqAck);
 
-    /**
-     *  Determine whether the ChipExchangeManager should not send an
-     *  acknowledgement.
-     *
-     *  For internal, debug use only.
-     */
-    bool ShouldDropAckDebug() const;
-
-    /**
-     *  Set whether the ChipExchangeManager should not send acknowledgements
-     *  for this context.
-     *
-     *  For internal, debug use only.
-     *
-     *  @param[in]  inDropAckDebug  A Boolean indicating whether (true) or not
-     *                         (false) the acknowledgements should be not
-     *                         sent for the exchange.
-     */
-    void SetDropAckDebug(bool inDropAckDebug);
-
     /**
      *  Determine whether there is already an acknowledgment pending to be sent to the peer on this exchange.
      *
@@ -159,29 +139,25 @@ class ReliableMessageContext
         /// When set, automatically request an acknowledgment whenever a message is sent via UDP.
         kFlagAutoRequestAck = (1u << 2),
 
-        /// Internal and debug only: when set, the exchange layer does not send an acknowledgment.
-        kFlagDropAckDebug = (1u << 3),
-
         /// When set, signifies there is a message which hasn't been acknowledged.
-        kFlagMessageNotAcked = (1u << 4),
+        kFlagMessageNotAcked = (1u << 3),
 
         /// When set, signifies that there is an acknowledgment pending to be sent back.
-        kFlagAckPending = (1u << 5),
+        kFlagAckPending = (1u << 4),
 
-        /// When set, signifies that there has once been an acknowledgment
-        /// pending to be sent back.  In that case,
-        /// mPendingPeerAckMessageCounter is a valid message counter value for
-        /// some message we have needed to acknowledge in the past.
-        kFlagAckMessageCounterIsValid = (1u << 6),
+        /// When set, signifies that mPendingPeerAckMessageCounter is valid.
+        /// The counter is valid once we receive a message which requests an ack.
+        /// Once mPendingPeerAckMessageCounter is valid, it never stops being valid.
+        kFlagAckMessageCounterIsValid = (1u << 5),
 
         /// When set, signifies that this exchange is waiting for a call to SendMessage.
-        kFlagWillSendMessage = (1u << 7),
+        kFlagWillSendMessage = (1u << 6),
 
         /// When set, we have had Close() or Abort() called on us already.
-        kFlagClosed = (1u << 8),
+        kFlagClosed = (1u << 7),
 
         /// When set, signifies that the exchange is requesting Sleepy End Device active mode.
-        kFlagActiveMode = (1u << 9),
+        kFlagActiveMode = (1u << 8),
     };
 
     BitFlags<Flags> mFlags; // Internal state flags
@@ -228,11 +204,6 @@ inline bool ReliableMessageContext::IsMessageNotAcked() const
     return mFlags.Has(Flags::kFlagMessageNotAcked);
 }
 
-inline bool ReliableMessageContext::ShouldDropAckDebug() const
-{
-    return mFlags.Has(Flags::kFlagDropAckDebug);
-}
-
 inline bool ReliableMessageContext::HasPiggybackAckPending() const
 {
     return mFlags.Has(Flags::kFlagAckMessageCounterIsValid);
@@ -253,11 +224,6 @@ inline void ReliableMessageContext::SetAckPending(bool inAckPending)
     mFlags.Set(Flags::kFlagAckPending, inAckPending);
 }
 
-inline void ReliableMessageContext::SetDropAckDebug(bool inDropAckDebug)
-{
-    mFlags.Set(Flags::kFlagDropAckDebug, inDropAckDebug);
-}
-
 inline void ReliableMessageContext::SetMessageNotAcked(bool messageNotAcked)
 {
     mFlags.Set(Flags::kFlagMessageNotAcked, messageNotAcked);