Address CI comments

src/lib/core/TLVBackingStore.h

@@ -156,7 +156,7 @@ class DLL_EXPORT TLVBackingStore
      */
     virtual CHIP_ERROR FinalizeBuffer(TLVWriter & writer, uint8_t * bufStart, uint32_t bufLen) = 0;
 
-    virtual bool IsSafeToReserve() { return false; }
+    virtual bool GetNewBufferWillAlwaysFail() { return false; }
 };
 
 } // namespace TLV

src/lib/core/TLVWriter.cpp

@@ -101,12 +101,9 @@ CHIP_ERROR TLVWriter::ReserveBuffer(uint32_t aBufferSize)
 {
     VerifyOrReturnError(mRemainingLen >= aBufferSize, CHIP_ERROR_NO_MEMORY);
 
-    uint32_t spaceLeftInCurrentBuffer        = mReservedSize + mRemainingLen;
-    bool canPossiblyAllocateAdditionalMemory = spaceLeftInCurrentBuffer < mMaxLen;
-
-    if (mBackingStore && canPossiblyAllocateAdditionalMemory)
+    if (mBackingStore)
     {
-        VerifyOrReturnError(mBackingStore->IsSafeToReserve(), CHIP_ERROR_INCORRECT_STATE);
+        VerifyOrReturnError(mBackingStore->GetNewBufferWillAlwaysFail(), CHIP_ERROR_INCORRECT_STATE);
     }
     mReservedSize += aBufferSize;
     mRemainingLen -= aBufferSize;

src/system/TLVPacketBufferBackingStore.h

@@ -80,14 +80,10 @@ class TLVPacketBufferBackingStore : public chip::TLV::TLVBackingStore
     CHIP_ERROR OnInit(chip::TLV::TLVWriter & writer, uint8_t *& bufStart, uint32_t & bufLen) override;
     CHIP_ERROR GetNewBuffer(chip::TLV::TLVWriter & writer, uint8_t *& bufStart, uint32_t & bufLen) override;
     CHIP_ERROR FinalizeBuffer(chip::TLV::TLVWriter & writer, uint8_t * bufStart, uint32_t bufLen) override;
-    virtual bool IsSafeToReserve() override
+    virtual bool GetNewBufferWillAlwaysFail() override
     {
-        // When using chained buffers there is no guarantee what the size of new buffer will
-        // be when calling GetNewBuffer. This makes it very difficult for a caller to safely
-        // ensure there is always enough space at the end of new buffer for reservation,
-        // when going from one buffer to the next.
-        // For non-chained buffers, caller is given one chunk of conigous memory so it is
-        // possible to reserve with buffer currently in use by caller.
+        // For non-chained buffers, caller is given one chunk of contiguous memory all calls to
+        // GetNewBuffer will fail with CHIP_ERROR_NO_MEMORY.
         return !mUseChainedBuffers;
     }
 

src/system/tests/TestTLVPacketBufferBackingStore.cpp

@@ -285,7 +285,7 @@ void TLVPacketBufferBackingStoreTest::TestWriterReserveUnreserveDoesNotOverflow(
         uint32_t lengthRemaining = writer.GetRemainingFreeLength();
         NL_TEST_ASSERT(inSuite, lengthRemaining == 1);
         // Lets try to overflow by getting next buffer in the chain,
-        // unreserving then writting until the end of the current buffer.
+        // unreserving then writing until the end of the current buffer.
         error = writer.Put(TLV::AnonymousTag(), static_cast<uint8_t>(7));
         NL_TEST_ASSERT(inSuite, error == CHIP_NO_ERROR);