weave/src/ble/WoBle.cpp

/*
 *
 *    Copyright (c) 2014-2017 Nest Labs, Inc.
 *    All rights reserved.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

/**
 *    @file
 *      This file implements types and an object for the Weave over
 *      Bluetooth Low Energy (WoBLE) byte-stream, connection-oriented
 *      adaptation of Weave for point-to-point Bluetooth Low Energy
 *      (BLE) links.
 *
 */

#include <BleLayer/BleConfig.h>

#if CONFIG_NETWORK_LAYER_BLE

#include <BleLayer/WoBle.h>
#if WEAVE_ENABLE_WOBLE_TEST
#include <BleLayer/WoBleTest.h>
#endif

#include <Weave/Support/logging/WeaveLogging.h>
#include <Weave/Support/CodeUtils.h>

// Define below to enable extremely verbose BLE-specific debug logging.
#undef NL_BTP_PROTOCOL_ENGINE_DEBUG_LOGGING_ENABLED

#ifdef NL_BTP_PROTOCOL_ENGINE_DEBUG_LOGGING_ENABLED
#define WeaveLogDebugBtpEngine(MOD, MSG, ...) WeaveLogError(MOD, MSG, ## __VA_ARGS__)
#else
#define WeaveLogDebugBtpEngine(MOD, MSG, ...)
#endif

#define NL_BLE_TRANSFER_PROTOCOL_HEADER_FLAGS_SIZE 1 // Size in bytes of enocded BTP fragment header flag bits
#define NL_BLE_TRANSFER_PROTOCOL_SEQUENCE_NUM_SIZE 1 // Size in bytes of encoded BTP sequence number
#define NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE 1 // Size in bytes of encoded BTP fragment acknowledgement number
#define NL_BLE_TRANSFER_PROTOCOL_MSG_LEN_SIZE 2 // Size in byte of encoded BTP total fragmented message length

#define NL_BLE_TRANSFER_PROTOCOL_MAX_HEADER_SIZE (NL_BLE_TRANSFER_PROTOCOL_HEADER_FLAGS_SIZE + \
                                                  NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE + \
                                                  NL_BLE_TRANSFER_PROTOCOL_SEQUENCE_NUM_SIZE + \
                                                  NL_BLE_TRANSFER_PROTOCOL_MSG_LEN_SIZE)

#define NL_BLE_TRANSFER_PROTOCOL_MID_FRAGMENT_MAX_HEADER_SIZE (NL_BLE_TRANSFER_PROTOCOL_HEADER_FLAGS_SIZE + \
                                                               NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE + \
                                                               NL_BLE_TRANSFER_PROTOCOL_SEQUENCE_NUM_SIZE)

#define NL_BLE_TRANSFER_PROTOCOL_STANDALONE_ACK_HEADER_SIZE (NL_BLE_TRANSFER_PROTOCOL_HEADER_FLAGS_SIZE + \
                                                             NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE + \
                                                             NL_BLE_TRANSFER_PROTOCOL_SEQUENCE_NUM_SIZE)


namespace nl {
namespace Ble {

static inline void IncSeqNum(SequenceNumber_t &a_seq_num)
{
    a_seq_num = 0xff & ((a_seq_num) + 1);
}

static inline bool DidReceiveData(uint8_t rx_flags)
{
    return (GetFlag(rx_flags, WoBle::kHeaderFlag_StartMessage) == true ||
            GetFlag(rx_flags, WoBle::kHeaderFlag_ContinueMessage) == true ||
            GetFlag(rx_flags, WoBle::kHeaderFlag_EndMessage) == true);
}

static void PrintBufDebug(PacketBuffer *buf)
{
#ifdef NL_BTP_PROTOCOL_ENGINE_DEBUG_LOGGING_ENABLED
    uint8_t *b = buf->Start();

    for (int i = 0; i < buf->DataLength(); i++)
    {
        WeaveLogError(Ble, "\t%02x", b[i]);
    }
#endif
}

const uint16_t WoBle::sDefaultFragmentSize  =  20; // 23-byte minimum ATT_MTU - 3 bytes for ATT operation header
const uint16_t WoBle::sMaxFragmentSize      = 128; // Size of write and indication characteristics

BLE_ERROR WoBle::Init(void *an_app_state, bool expect_first_ack)
{
    mAppState = an_app_state;
    mRxState = kState_Idle;
    mRxBuf = NULL;
    mRxNewestUnackedSeqNum = 0;
    mRxOldestUnackedSeqNum = 0;
    mRxFragmentSize = sDefaultFragmentSize;
    mTxState = kState_Idle;
    mTxBuf = NULL;
    mTxFragmentSize = sDefaultFragmentSize;
    mRxCharCount = 0;
    mRxPacketCount = 0;
    mTxCharCount = 0;
    mTxPacketCount = 0;
    mTxNewestUnackedSeqNum = 0;
    mTxOldestUnackedSeqNum = 0;
#if WEAVE_ENABLE_WOBLE_TEST
	mTxPacketType = kType_Data;		// Default WoBle Data packet
	mRxPacketType = kType_Data;		// Default WoBle Data packet
#endif

    if (expect_first_ack == true)
    {
        mTxNextSeqNum = 1;
        mExpectingAck = true;
        mRxNextSeqNum = 0;
    }
    else
    {
        mTxNextSeqNum = 0;
        mExpectingAck = false;
        mRxNextSeqNum = 1;
    }

    return BLE_NO_ERROR;
}

SequenceNumber_t WoBle::GetAndIncrementNextTxSeqNum()
{
    SequenceNumber_t ret = mTxNextSeqNum;

    // If not already expecting ack...
    if (mExpectingAck == false)
    {
        mExpectingAck = true;
        mTxOldestUnackedSeqNum = mTxNextSeqNum;
    }

    // Update newest unacknowledged sequence number.
    mTxNewestUnackedSeqNum = mTxNextSeqNum;

    // Increment mTxNextSeqNum.
    IncSeqNum(mTxNextSeqNum);

    return ret;
}

SequenceNumber_t WoBle::GetAndRecordRxAckSeqNum()
{
    SequenceNumber_t ret = mRxNewestUnackedSeqNum;

    mRxNewestUnackedSeqNum = mRxNextSeqNum;
    mRxOldestUnackedSeqNum = mRxNextSeqNum;

    return ret;
}

bool WoBle::HasUnackedData() const
{
    return (mRxOldestUnackedSeqNum != mRxNextSeqNum);
}

bool WoBle::IsValidAck(SequenceNumber_t ack_num) const
{
    WeaveLogDebugBtpEngine(Ble, "entered IsValidAck, ack = %u, oldest = %u, newest = %u", ack_num, mTxOldestUnackedSeqNum, mTxNewestUnackedSeqNum);

    // Return false if not awaiting any ack.
    if (mExpectingAck == false)
    {
        WeaveLogDebugBtpEngine(Ble, "unexpected ack is invalid");
        return false;
    }

    // Assumption: maximum valid sequence number equals maximum value of SequenceNumber_t.

    if (mTxNewestUnackedSeqNum >= mTxOldestUnackedSeqNum) // If current unacked interval does NOT wrap...
    {
        return (ack_num <= mTxNewestUnackedSeqNum && ack_num >= mTxOldestUnackedSeqNum);
    }
    else // Else, if current unacked interval DOES wrap...
    {
        return (ack_num <= mTxNewestUnackedSeqNum || ack_num >= mTxOldestUnackedSeqNum);
    }
}

BLE_ERROR WoBle::HandleAckReceived(SequenceNumber_t ack_num)
{
    BLE_ERROR err = BLE_NO_ERROR;

    WeaveLogDebugBtpEngine(Ble, "entered HandleAckReceived, ack_num = %u", ack_num);

    // Ensure ack_num falls within range of ack values we're expecting.
    VerifyOrExit(IsValidAck(ack_num) == true, err = BLE_ERROR_INVALID_ACK);

    if (mTxNewestUnackedSeqNum == ack_num) // If ack is for newest outstanding unacknowledged fragment...
    {
        mTxOldestUnackedSeqNum = ack_num;

        // All oustanding fragments have been acknowledged.
        mExpectingAck = false;
    }
    else // If ack is valid, but not for newest oustanding unacknowledged fragment...
    {
        // Update newest unacknowledged fragment to one past that which was just acknowledged.
        mTxOldestUnackedSeqNum = ack_num;
        IncSeqNum(mTxOldestUnackedSeqNum);
    }

exit:
    return err;
}

// Calling convention:
//   EncodeStandAloneAck may only be called if data arg is commited for immediate, synchronous subsequent transmission.
BLE_ERROR WoBle::EncodeStandAloneAck(PacketBuffer *data)
{
    BLE_ERROR err = BLE_NO_ERROR;
    uint8_t *characteristic;

    // Ensure enough headroom exists for the lower BLE layers.
    VerifyOrExit(data->EnsureReservedSize(WEAVE_CONFIG_BLE_PKT_RESERVED_SIZE) == true, err = BLE_ERROR_NO_MEMORY);

    // Ensure enough space for standalone ack payload.
    VerifyOrExit(data->MaxDataLength() >= NL_BLE_TRANSFER_PROTOCOL_STANDALONE_ACK_HEADER_SIZE, err = BLE_ERROR_NO_MEMORY);
    characteristic = data->Start();

    // Since there's no preexisting message payload, we can write BTP header without adjusting data start pointer.
    characteristic[0] = kHeaderFlag_FragmentAck;

    // Acknowledge most recently received sequence number.
    characteristic[1] = GetAndRecordRxAckSeqNum();
    WeaveLogDebugBtpEngine(Ble, "===> encoded stand-alone ack = %u", characteristic[1]);

    // Include sequence number for stand-alone ack itself.
    characteristic[2] = GetAndIncrementNextTxSeqNum();

    // Set ack payload data length.
    data->SetDataLength(NL_BLE_TRANSFER_PROTOCOL_STANDALONE_ACK_HEADER_SIZE);

exit:
    return err;
}

// Calling convention:
//   WoBle does not retain ownership of reassembled messages, layer above needs to free when done.
//
//   WoBle does not reset itself on error. Upper layer should free outbound message and inbound reassembly buffers
//   if there is a problem.

// HandleCharacteristicReceived():
//
//   Non-NULL characteristic data arg is always either designated as or appended to the message reassembly buffer,
//   or freed if it holds a stand-alone ack. In all cases, caller must clear its reference to data arg when this
//   function returns.
//
//   Upper layer must immediately clean up and reinitialize protocol engine if returned err != BLE_NO_ERROR.
BLE_ERROR WoBle::HandleCharacteristicReceived(PacketBuffer *data, SequenceNumber_t &receivedAck, bool &didReceiveAck)
{
    BLE_ERROR err = BLE_NO_ERROR;
    uint8_t rx_flags = 0;
    uint8_t cursor = 0;
    uint8_t *characteristic = data->Start();

    VerifyOrExit(data != NULL, err = BLE_ERROR_BAD_ARGS);

    mRxCharCount++;

    // Get header flags, always in first byte.
    rx_flags = characteristic[cursor++];
#if WEAVE_ENABLE_WOBLE_TEST
    if (GetFlag(rx_flags, kHeaderFlag_CommandMessage) == true)
		SetRxPacketType(kType_Control);
	else
		SetRxPacketType(kType_Data);
#endif

    didReceiveAck = GetFlag(rx_flags, kHeaderFlag_FragmentAck);

    // Get ack number, if any.
    if (didReceiveAck == true)
    {
        receivedAck = characteristic[cursor++];

        err = HandleAckReceived(receivedAck);
        SuccessOrExit(err);
    }

    // Get sequence number.
    mRxNewestUnackedSeqNum = characteristic[cursor++];

    // Verify that received sequence number is the next one we'd expect.
    VerifyOrExit(mRxNewestUnackedSeqNum == mRxNextSeqNum, err = BLE_ERROR_INVALID_BTP_SEQUENCE_NUMBER);

    // Increment next expected rx sequence number.
    IncSeqNum(mRxNextSeqNum);

    // If fragment was stand-alone ack, we're done here; no payload for message reassembler.
    if (DidReceiveData(rx_flags) == false)
    {
        // Free stand-alone ack buffer.
        PacketBuffer::Free(data);
        data = NULL;

        ExitNow();
    }

    // Truncate the incoming fragment length by the mRxFragmentSize as the negotiated
    // mRxFragnentSize may be smaller than the characteristic size.
    data->SetDataLength(nl::Weave::min(data->DataLength(), mRxFragmentSize));

    WeaveLogDebugBtpEngine(Ble, ">>> BTP reassembler received data:");
    PrintBufDebug(data);

    if (mRxState == kState_Idle)
    {
        // Verify StartMessage header flag set.
        VerifyOrExit(rx_flags & kHeaderFlag_StartMessage, err = BLE_ERROR_INVALID_BTP_HEADER_FLAGS);

        mRxLength = (characteristic[(cursor + 1)] << 8) | characteristic[cursor];
        cursor += 2;

        mRxState = kState_InProgress;

        data->SetStart(&(characteristic[cursor]));

        // Create a new buffer for use as the Rx re-assembly area.
        mRxBuf = PacketBuffer::New();

        VerifyOrExit(mRxBuf != NULL, err = BLE_ERROR_NO_MEMORY);

        mRxBuf->AddToEnd(data);
        mRxBuf->CompactHead(); // will free 'data' and adjust rx buf's end/length
        data = NULL;
    }
    else if (mRxState == kState_InProgress)
    {
        // Verify StartMessage header flag NOT set, since we're in the middle of receiving a message.
        VerifyOrExit((rx_flags & kHeaderFlag_StartMessage) == 0, err = BLE_ERROR_INVALID_BTP_HEADER_FLAGS);

        // Verify ContinueMessage or EndMessage header flag set.
        VerifyOrExit((rx_flags & kHeaderFlag_ContinueMessage) || (rx_flags & kHeaderFlag_EndMessage),
                err = BLE_ERROR_INVALID_BTP_HEADER_FLAGS);

        // Add received fragment to reassembled message buffer.
        data->SetStart(&(characteristic[cursor]));
        mRxBuf->AddToEnd(data);
        mRxBuf->CompactHead(); // will free 'data' and adjust rx buf's end/length
        data = NULL;

        // For now, limit WoBle message size to max length of 1 pbuf, as we do for Weave messages sent via IP.
           // TODO add support for WoBle messages longer than 1 pbuf
        VerifyOrExit(mRxBuf->Next() == NULL, err = BLE_ERROR_RECEIVED_MESSAGE_TOO_BIG);
    }
    else
    {
        err = BLE_ERROR_REASSEMBLER_INCORRECT_STATE;
        ExitNow();
    }

    if (rx_flags & kHeaderFlag_EndMessage)
    {
        // Trim remainder, if any, of received PacketBuffer based on sender-specified length of reassembled message.
        int padding = mRxBuf->DataLength() - mRxLength;

        if (padding > 0)
        {
            mRxBuf->SetDataLength(mRxLength);
        }

        // Ensure all received fragments add up to sender-specified total message size.
        VerifyOrExit(mRxBuf->DataLength() == mRxLength, err = BLE_ERROR_REASSEMBLER_MISSING_DATA);

        // We've reassembled the entire message.
        mRxState = kState_Complete;
        mRxPacketCount++;
    }

exit:
    if (err != BLE_NO_ERROR)
    {
        mRxState = kState_Error;

        // Dump protocol engine state, plus header flags and received data length.
        WeaveLogError(Ble, "HandleCharacteristicReceived failed, err = %d, rx_flags = %u", err, rx_flags);
        if (didReceiveAck == true)
        {
            WeaveLogError(Ble, "With rx'd ack = %u", receivedAck);
        }
        if (mRxBuf != NULL)
        {
            WeaveLogError(Ble, "With rx buf data length = %u", mRxBuf->DataLength());
        }
        LogState();

        if (data != NULL)
        {
            // Tack received data onto rx buffer, to be freed when end point resets protocol engine on close.
            if (mRxBuf != NULL)
            {
                mRxBuf->AddToEnd(data);
            }
            else
            {
                mRxBuf = data;
            }
        }
    }

    return err;
}

PacketBuffer *WoBle::RxPacket()
{
    return mRxBuf;
}

bool WoBle::ClearRxPacket()
{
    if (mRxState == kState_Complete)
    {
        mRxState = kState_Idle;
        mRxBuf = NULL;
        // do not reset mRxNextSeqNum
        return true;
    }

    return false;
}

// Calling convention:
//   May only be called if data arg is commited for immediate, synchronous subsequent transmission.
//   Returns false on error. Caller must free data arg on error.
bool WoBle::HandleCharacteristicSend(PacketBuffer *data, bool send_ack)
{
    uint8_t *characteristic;
    mTxCharCount++;

    if (send_ack && !HasUnackedData())
    {
        WeaveLogError(Ble, "HandleCharacteristicSend: send_ack true, but nothing to acknowledge.");
        return false;
    }

    if (mTxState == kState_Idle)
    {
        if (data == NULL)
        {
            return false;
        }

        mTxBuf = data;
        mTxState = kState_InProgress;
        mTxLength = mTxBuf->DataLength();

        WeaveLogDebugBtpEngine(Ble, ">>> WoBle preparing to send whole message:");
        PrintBufDebug(data);

        // Determine fragment header size.
        uint8_t header_size = (send_ack == true) ? NL_BLE_TRANSFER_PROTOCOL_MAX_HEADER_SIZE :
                          (NL_BLE_TRANSFER_PROTOCOL_MAX_HEADER_SIZE - NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE);

        // Ensure enough headroom exists for the BTP header, and any headroom needed by the lower BLE layers.
        if (!mTxBuf->EnsureReservedSize(header_size + WEAVE_CONFIG_BLE_PKT_RESERVED_SIZE))
        {
            // handle error
            WeaveLogError(Ble, "HandleCharacteristicSend: not enough headroom");
            mTxState = kState_Error;
            mTxBuf = NULL; // Avoid double-free after assignment above, as caller frees data on error.

            return false;
        }

        // prepend header.
        characteristic = mTxBuf->Start();
        characteristic -= header_size;
        mTxBuf->SetStart(characteristic);
        uint8_t cursor = 1; // first position past header flags byte

        characteristic[0] = kHeaderFlag_StartMessage;

#if WEAVE_ENABLE_WOBLE_TEST
        if (TxPacketType() == kType_Control)
            SetFlag(characteristic[0], kHeaderFlag_CommandMessage, true);
#endif

        if (send_ack == true)
        {
            SetFlag(characteristic[0], kHeaderFlag_FragmentAck, true);
            characteristic[cursor++] = GetAndRecordRxAckSeqNum();
            WeaveLogDebugBtpEngine(Ble, "===> encoded piggybacked ack, ack_num = %u", characteristic[cursor-1]);
        }

        characteristic[cursor++] = GetAndIncrementNextTxSeqNum();
        characteristic[cursor++] = mTxLength & 0xff;
        characteristic[cursor++] = mTxLength >> 8;

        if ((mTxLength + cursor) <= mTxFragmentSize)
        {
            mTxBuf->SetDataLength(mTxLength + cursor);
            mTxLength = 0;
            SetFlag(characteristic[0], kHeaderFlag_EndMessage, true);
            mTxState = kState_Complete;
            mTxPacketCount++;
        }
        else
        {
            mTxBuf->SetDataLength(mTxFragmentSize);
            mTxLength -= mTxFragmentSize - cursor;
        }

        WeaveLogDebugBtpEngine(Ble, ">>> WoBle preparing to send first fragment:");
        PrintBufDebug(data);
    }
    else if (mTxState == kState_InProgress)
    {
        if (data != NULL)
        {
            return false;
        }

        // advance past the previous fragment
        characteristic = mTxBuf->Start();
        characteristic += mTxFragmentSize;

        // prepend header
        characteristic -= (send_ack == true) ? NL_BLE_TRANSFER_PROTOCOL_MID_FRAGMENT_MAX_HEADER_SIZE :
                      (NL_BLE_TRANSFER_PROTOCOL_MID_FRAGMENT_MAX_HEADER_SIZE - NL_BLE_TRANSFER_PROTOCOL_ACK_SIZE);
        mTxBuf->SetStart(characteristic);
        uint8_t cursor = 1; // first position past header flags byte

        characteristic[0] = kHeaderFlag_ContinueMessage;

#if WEAVE_ENABLE_WOBLE_TEST
        if (TxPacketType() == kType_Control)
            SetFlag(characteristic[0], kHeaderFlag_CommandMessage, true);
#endif

        if (send_ack == true)
        {
            SetFlag(characteristic[0], kHeaderFlag_FragmentAck, true);
            characteristic[cursor++] = GetAndRecordRxAckSeqNum();
            WeaveLogDebugBtpEngine(Ble, "===> encoded piggybacked ack, ack_num = %u", characteristic[cursor-1]);
        }

        characteristic[cursor++] = GetAndIncrementNextTxSeqNum();

        if ((mTxLength + cursor) <= mTxFragmentSize)
        {
            mTxBuf->SetDataLength(mTxLength + cursor);
            mTxLength = 0;
            SetFlag(characteristic[0], kHeaderFlag_EndMessage, true);
            mTxState = kState_Complete;
            mTxPacketCount++;
        }
        else
        {
            mTxBuf->SetDataLength(mTxFragmentSize);
            mTxLength -= mTxFragmentSize - cursor;
        }

        WeaveLogDebugBtpEngine(Ble, ">>> WoBle preparing to send additional fragment:");
        PrintBufDebug(mTxBuf);
    }
    else
    {
        // Invalid tx state.
        return false;
    }

    return true;
}

PacketBuffer *WoBle::TxPacket()
{
    return mTxBuf;
}

bool WoBle::ClearTxPacket()
{
    if (mTxState == kState_Complete)
    {
        mTxState = kState_Idle;
        mTxBuf = NULL;
        // do not reset mTxNextSeqNum
        return true;
    }

    return false;
}

void WoBle::LogState() const
{
  WeaveLogError(Ble, "mAppState: %p", mAppState);

  WeaveLogError(Ble, "mRxFragmentSize: %d", mRxFragmentSize);
  WeaveLogError(Ble, "mRxState: %d", mRxState);
  WeaveLogError(Ble, "mRxBuf: %p", mRxBuf);
  WeaveLogError(Ble, "mRxNextSeqNum: %d", mRxNextSeqNum);
  WeaveLogError(Ble, "mRxNewestUnackedSeqNum: %d", mRxNewestUnackedSeqNum);
  WeaveLogError(Ble, "mRxOldestUnackedSeqNum: %d", mRxOldestUnackedSeqNum);
  WeaveLogError(Ble, "mRxCharCount: %d", mRxCharCount);
  WeaveLogError(Ble, "mRxPacketCount: %d", mRxPacketCount);

  WeaveLogError(Ble, "mTxFragmentSize: %d", mTxFragmentSize);
  WeaveLogError(Ble, "mTxState: %d", mTxState);
  WeaveLogError(Ble, "mTxBuf: %p", mTxBuf);
  WeaveLogError(Ble, "mTxNextSeqNum: %d", mTxNextSeqNum);
  WeaveLogError(Ble, "mTxNewestUnackedSeqNum: %d", mTxNewestUnackedSeqNum);
  WeaveLogError(Ble, "mTxOldestUnackedSeqNum: %d", mTxOldestUnackedSeqNum);
  WeaveLogError(Ble, "mTxCharCount: %d", mTxCharCount);
  WeaveLogError(Ble, "mTxPacketCount: %d", mTxPacketCount);
}

void WoBle::LogStateDebug() const
{
#ifdef NL_BTP_PROTOCOL_ENGINE_DEBUG_LOGGING_ENABLED
	LogState();
#endif
}

//
// Unit Testing
//


bool WoBle::UnitTest1()
{
    PacketBuffer *first_packet;
    SequenceNumber_t rcvd_ack;
    bool did_rcv_ack;
    bool rc = true;

    Init(NULL, false);
    first_packet = PacketBuffer::New(5);

    if (first_packet->AvailableDataLength() < 5)
    {
        PacketBuffer::Free(first_packet);
        return false;
    }

    first_packet->SetDataLength(5, NULL);
    uint8_t *data = first_packet->Start();

    if (data == NULL)
    {
        PacketBuffer::Free(first_packet);
        return false;
    }

    data[0] = 0x05;
    data[1] = 1;
    data[2] = 1;
    data[3] = 0;
    data[4] = 0xff; // payload

    if (!HandleCharacteristicReceived(first_packet, rcvd_ack, did_rcv_ack))
        rc = false;

    if (mRxState != kState_Complete)
        rc = false;

    Init(NULL, false);
    PacketBuffer::Free(first_packet);

    return rc;
}

bool WoBle::UnitTest2()
{
    PacketBuffer *first_packet;
    PacketBuffer *second_packet;
    SequenceNumber_t rcvd_ack;
    bool did_rcv_ack;
    bool rc = true;

    Init(NULL, false);
    first_packet = PacketBuffer::New(10);
    first_packet->SetDataLength(5, NULL);
    uint8_t *data = first_packet->Start();

    if (data == NULL)
    {
        PacketBuffer::Free(first_packet);
        return false;
    }

    data[0] = kHeaderFlag_StartMessage;
    data[1] = 1;
    data[2] = 2;
    data[3] = 0;
    data[4] = 0xfe; // payload

    if (!HandleCharacteristicReceived(first_packet, rcvd_ack, did_rcv_ack))
    {
        PacketBuffer::Free(first_packet);
        return false;
    }

    if (mRxState != kState_InProgress)
    {
        PacketBuffer::Free(first_packet);
        rc = false;
    }

    second_packet = PacketBuffer::New(3);
    second_packet->SetDataLength(3, NULL);
    data = second_packet->Start();

    if (data == NULL)
    {
        PacketBuffer::Free(first_packet);
        PacketBuffer::Free(second_packet);
        return false;
    }

    data[0] = kHeaderFlag_EndMessage;
    data[1] = 2;
    data[4] = 0xff; // payload

    if (!HandleCharacteristicReceived(second_packet, rcvd_ack, did_rcv_ack))
    {
        rc = false;
    }

    if (mRxState != kState_Complete)
    {
        rc = false;
    }

    Init(NULL, false);
    PacketBuffer::Free(first_packet);

    return rc;
}

bool WoBle::UnitTest3()
{
  PacketBuffer *first_packet;
  PacketBuffer *second_packet;
  PacketBuffer *last_packet;
  SequenceNumber_t rcvd_ack;
  bool did_rcv_ack;
  bool rc = true;

  Init(NULL, false);
  first_packet = PacketBuffer::New(10);
  first_packet->SetDataLength(5, NULL);
  uint8_t *data = first_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    return false;
  }
  data[0] = kHeaderFlag_StartMessage;
  data[1] = 1;
  data[2] = 3;
  data[3] = 0;
  data[4] = 0xfd; // payload

  if (!HandleCharacteristicReceived(first_packet, rcvd_ack, did_rcv_ack)) {
    PacketBuffer::Free(first_packet);
    return false;
  }
  if (mRxState != kState_InProgress) {
    PacketBuffer::Free(first_packet);
    rc = false;
  }

  second_packet = PacketBuffer::New(3);
  second_packet->SetDataLength(3, NULL);
  data = second_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    PacketBuffer::Free(second_packet);
    return false;
  }
  data[0] = kHeaderFlag_ContinueMessage;
  data[1] = 2;
  data[4] = 0xfe; // payload

  if (!HandleCharacteristicReceived(second_packet, rcvd_ack, did_rcv_ack)) {
    PacketBuffer::Free(first_packet);
    PacketBuffer::Free(second_packet);
    return false;
  }

  if (mRxState != kState_InProgress) {
    PacketBuffer::Free(first_packet);
    PacketBuffer::Free(second_packet);
    return false;
  }

  last_packet = PacketBuffer::New(3);
  last_packet->SetDataLength(3, NULL);
  data = last_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    PacketBuffer::Free(last_packet);
    return false;
  }
  data[0] = kHeaderFlag_EndMessage;
  data[1] = 3;
  data[4] = 0xff; // payload

  if (!HandleCharacteristicReceived(last_packet, rcvd_ack, did_rcv_ack)) {
    rc = false;
  }

  if (mRxState != kState_Complete) {
    rc = false;
  }

  Init(NULL, false);
  PacketBuffer::Free(first_packet);
  return rc;
}

bool WoBle::UnitTest4()
{
  PacketBuffer *first_packet;
  bool rc = true;

  Init(NULL, false);
  first_packet = PacketBuffer::New(10);
  first_packet->SetDataLength(1, NULL);
  uint8_t *data = first_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    return false;
  }
  data[0] = 0xff; // payload

  if ((!HandleCharacteristicSend(first_packet, false)) ||
      (first_packet->DataLength() != 5) ||
      (mTxState != kState_Complete)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  Init(NULL, false);
  PacketBuffer::Free(first_packet);
  return rc;
}

bool WoBle::UnitTest5()
{
  PacketBuffer *first_packet;

  Init(NULL, false);
  first_packet = PacketBuffer::New(140);
  first_packet->SetDataLength(140, NULL);
  uint8_t *data = first_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    return false;
  }
  for (int i = 0; i < 140; i++) {
    data[i] = i; // payload
  }

  if (!HandleCharacteristicSend(first_packet, false) ||
      (first_packet->DataLength() != 128) ||
      (mTxState != kState_InProgress)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  if ((!HandleCharacteristicSend(NULL, false)) ||
      (mTxState != kState_Complete) ||
      (first_packet->DataLength() != 18)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  Init(NULL, false);
  PacketBuffer::Free(first_packet);
  return true;
}

// Send 300-byte payload.
// First packet: 4 byte header + 124 byte payload
// Second packet: 2 byte header + 126 byte payload
// Third packet: 2 byte header + 50 byte payload
bool WoBle::UnitTest6()
{
  PacketBuffer *first_packet;
  bool rc = true;

  Init(NULL, false);
  first_packet = PacketBuffer::New(300);
  first_packet->SetDataLength(300, NULL);
  uint8_t *data = first_packet->Start();
  if (data == NULL) {
    PacketBuffer::Free(first_packet);
    return false;
  }
  for (int i = 0; i < 300; i++) {
    data[i] = i; // payload
  }

  if (!HandleCharacteristicSend(first_packet, false) ||
      (first_packet->DataLength() != 128) ||
      (mTxState != kState_InProgress)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  if (!HandleCharacteristicSend(NULL, false) ||
      (mTxState != kState_InProgress) ||
      (first_packet->DataLength() != 128)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  if (!HandleCharacteristicSend(NULL, false) ||
      (mTxState != kState_Complete) ||
      (first_packet->DataLength() != 52)) {
    PacketBuffer::Free(first_packet);
    return false;
  }

  Init(NULL, false);
  PacketBuffer::Free(first_packet);
  return rc;
}

bool WoBle::UnitTest()
{
  bool rc;

  rc = UnitTest1();
  rc = rc && UnitTest2();
  rc = rc && UnitTest3();
  rc = rc && UnitTest4();
  rc = rc && UnitTest5();
  rc = rc && UnitTest6();
  if (!rc) {
    WeaveDie();
  }

  return rc;
}

} /* namespace Ble */
} /* namespace nl */

#endif /* CONFIG_NETWORK_LAYER_BLE */