[message] change Message::Free() to return void (#2071)

include/openthread/message.h

@@ -56,8 +56,6 @@ extern "C" {
  *
  * @param[in]  aMessage  A pointer to a message buffer.
  *
- * @retval OT_ERROR_NONE  Successfully freed the message buffer.
- *
  * @sa otMessageAppend
  * @sa otMessageGetLength
  * @sa otMessageSetLength
@@ -66,7 +64,7 @@ extern "C" {
  * @sa otMessageRead
  * @sa otMessageWrite
  */
-otError otMessageFree(otMessage *aMessage);
+void otMessageFree(otMessage *aMessage);
 
 /**
  * Get the message length in bytes.

src/core/api/message_api.cpp

@@ -38,9 +38,9 @@
 
 using namespace ot;
 
-otError otMessageFree(otMessage *aMessage)
+void otMessageFree(otMessage *aMessage)
 {
-    return static_cast<Message *>(aMessage)->Free();
+    static_cast<Message *>(aMessage)->Free();
 }
 
 uint16_t otMessageGetLength(otMessage *aMessage)

src/core/common/message.cpp

@@ -89,7 +89,7 @@ exit:
     return message;
 }
 
-otError MessagePool::Free(Message *aMessage)
+void MessagePool::Free(Message *aMessage)
 {
     assert(aMessage->Next(MessageInfo::kListAll) == NULL &&
            aMessage->Prev(MessageInfo::kListAll) == NULL);
@@ -97,7 +97,7 @@ otError MessagePool::Free(Message *aMessage)
     assert(aMessage->Next(MessageInfo::kListInterface) == NULL &&
            aMessage->Prev(MessageInfo::kListInterface) == NULL);
 
-    return FreeBuffers(static_cast<Buffer *>(aMessage));
+    FreeBuffers(static_cast<Buffer *>(aMessage));
 }
 
 Buffer *MessagePool::NewBuffer(void)
@@ -128,13 +128,11 @@ Buffer *MessagePool::NewBuffer(void)
     return buffer;
 }
 
-otError MessagePool::FreeBuffers(Buffer *aBuffer)
+void MessagePool::FreeBuffers(Buffer *aBuffer)
 {
-    Buffer *tmpBuffer;
-
     while (aBuffer != NULL)
     {
-        tmpBuffer = aBuffer->GetNextBuffer();
+        Buffer *tmpBuffer = aBuffer->GetNextBuffer();
 #if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
         otPlatMessagePoolFree(&GetInstance(), aBuffer);
 #else // OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
@@ -144,8 +142,6 @@ otError MessagePool::FreeBuffers(Buffer *aBuffer)
 #endif // OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
         aBuffer = tmpBuffer;
     }
-
-    return OT_ERROR_NONE;
 }
 
 otError MessagePool::ReclaimBuffers(int aNumBuffers)
@@ -260,9 +256,9 @@ exit:
     return error;
 }
 
-otError Message::Free(void)
+void Message::Free(void)
 {
-    return GetMessagePool()->Free(this);
+    GetMessagePool()->Free(this);
 }
 
 Message *Message::GetNext(void) const

src/core/common/message.hpp

@@ -235,7 +235,7 @@ public:
      * This method frees this message buffer.
      *
      */
-    otError Free(void);
+    void Free(void);
 
     /**
      * This method returns a pointer to the next message in the same interface list.
@@ -1126,11 +1126,8 @@ public:
      *
      * @param[in]  aMessage  The message to free.
      *
-     * @retval OT_ERROR_NONE          Successfully freed the message.
-     * @retval OT_ERROR_INVALID_ARGS  The message is already freed.
-     *
      */
-    otError Free(Message *aMessage);
+    void Free(Message *aMessage);
 
     /**
      * This method returns a pointer to the first message (head) in the all-messages list.
@@ -1169,7 +1166,7 @@ private:
     };
 
     Buffer *NewBuffer(void);
-    otError FreeBuffers(Buffer *aBuffer);
+    void FreeBuffers(Buffer *aBuffer);
     otError ReclaimBuffers(int aNumBuffers);
     PriorityQueue *GetAllMessagesQueue(void) { return &mAllQueue; }
 

src/core/crypto/mbedtls.cpp

@@ -53,7 +53,7 @@ static void *CAlloc(size_t aCount, size_t aSize)
 
 static void Free(void *aPointer)
 {
-    return otGetInstance()->mMbedTlsHeap.Free(aPointer);
+    otGetInstance()->mMbedTlsHeap.Free(aPointer);
 }
 
 MbedTls::MbedTls(void)

tests/unit/test_message.cpp

@@ -66,8 +66,7 @@ void TestMessage(void)
                  "Message compare failed\n");
     VerifyOrQuit(message->GetLength() == 1024,
                  "Message::GetLength failed\n");
-    SuccessOrQuit(message->Free(),
-                  "Message::Free failed\n");
+    message->Free();
 
     testFreeInstance(instance);
 }

tests/unit/test_ncp_buffer.cpp

@@ -769,7 +769,7 @@ void TestNcpFrameBuffer(void)
     SuccessOrQuit(message->SetLength(sizeof(sMysteryText)), "Could not set the length of message.");
     message->Write(0, sizeof(sMysteryText), sMysteryText);
     VerifyOrQuit(ncpBuffer.InFrameFeedMessage(message) == OT_ERROR_INVALID_STATE, "Incorrect error status");
-    SuccessOrQuit(message->Free(), "Failed to free allocated message");
+    message->Free();
     VerifyOrQuit(ncpBuffer.InFrameEnd() == OT_ERROR_INVALID_STATE, "Incorrect error status");
     VerifyAndRemoveFrame2(ncpBuffer);
     VerifyAndRemoveFrame1(ncpBuffer);