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fuchsia / third_party / openthread / 4f5162811a5300d4c8540c52db9090649a9762b3 / . / src / core / common / message.hpp
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/*
* Copyright (c) 2016, The OpenThread Authors.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holder nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @file
* This file includes definitions for the message buffer pool and message buffers.
*/
#ifndef MESSAGE_HPP_
#define MESSAGE_HPP_
#include "openthread-core-config.h"
#include <stdint.h>
#include <openthread/message.h>
#include <openthread/platform/messagepool.h>
#include "common/as_core_type.hpp"
#include "common/clearable.hpp"
#include "common/code_utils.hpp"
#include "common/const_cast.hpp"
#include "common/data.hpp"
#include "common/encoding.hpp"
#include "common/iterator_utils.hpp"
#include "common/linked_list.hpp"
#include "common/locator.hpp"
#include "common/non_copyable.hpp"
#include "common/pool.hpp"
#include "common/timer.hpp"
#include "common/type_traits.hpp"
#include "mac/mac_types.hpp"
#include "thread/child_mask.hpp"
#include "thread/link_quality.hpp"
/**
* This struct represents an opaque (and empty) type for an OpenThread message buffer.
*
*/
struct otMessage
{
};
namespace ot {
namespace Crypto {
class AesCcm;
class Sha256;
class HmacSha256;
} // namespace Crypto
/**
* @addtogroup core-message
*
* @brief
* This module includes definitions for the message buffer pool and message buffers.
*
* @{
*
*/
/**
* This macro frees a given message buffer if not `nullptr`.
*
* This macro and the ones that follow contain small but common code patterns used in many of the core modules. They
* are intentionally defined as macros instead of inline methods/functions to ensure that they are fully inlined.
* Note that an `inline` method/function is not necessarily always inlined by the toolchain and not inlining such
* small implementations can add a rather large code-size overhead.
*
* @param[in] aMessage A pointer to a `Message` to free (can be `nullptr`).
*
*/
#define FreeMessage(aMessage) \
do \
{ \
if ((aMessage) != nullptr) \
{ \
(aMessage)->Free(); \
} \
} while (false)
/**
* This macro frees a given message buffer if a given `Error` indicates an error.
*
* The parameter @p aMessage can be `nullptr` in which case this macro does nothing.
*
* @param[in] aMessage A pointer to a `Message` to free (can be `nullptr`).
* @param[in] aError The `Error` to check.
*
*/
#define FreeMessageOnError(aMessage, aError) \
do \
{ \
if (((aError) != kErrorNone) && ((aMessage) != nullptr)) \
{ \
(aMessage)->Free(); \
} \
} while (false)
/**
* This macro frees a given message buffer if a given `Error` indicates an error and sets the `aMessage` to `nullptr`.
*
* @param[in] aMessage A pointer to a `Message` to free (can be `nullptr`).
* @param[in] aError The `Error` to check.
*
*/
#define FreeAndNullMessageOnError(aMessage, aError) \
do \
{ \
if (((aError) != kErrorNone) && ((aMessage) != nullptr)) \
{ \
(aMessage)->Free(); \
(aMessage) = nullptr; \
} \
} while (false)
constexpr uint16_t kNumBuffers = OPENTHREAD_CONFIG_NUM_MESSAGE_BUFFERS;
constexpr uint16_t kBufferSize = OPENTHREAD_CONFIG_MESSAGE_BUFFER_SIZE;
class Message;
class MessagePool;
class MessageQueue;
class PriorityQueue;
class ThreadLinkInfo;
/**
* This class represents a Message buffer.
*
*/
class Buffer : public otMessageBuffer, public LinkedListEntry<Buffer>
{
friend class Message;
public:
/**
* This method returns a pointer to the next message buffer.
*
* @returns A pointer to the next message buffer.
*
*/
Buffer *GetNextBuffer(void) { return GetNext(); }
/**
* This method returns a pointer to the next message buffer.
*
* @returns A pointer to the next message buffer.
*
*/
const Buffer *GetNextBuffer(void) const { return GetNext(); }
/**
* This method sets the pointer to the next message buffer.
*
* @param[in] aNext A pointer to the next buffer.
*
*/
void SetNextBuffer(Buffer *aNext) { SetNext(aNext); }
protected:
struct Metadata
{
Message * mNext; // Next message in a doubly linked list.
Message * mPrev; // Previous message in a doubly linked list.
MessagePool *mMessagePool; // Message pool for this message.
void * mQueue; // The queue where message is queued (if any). Queue type from `mInPriorityQ`.
uint32_t mDatagramTag; // The datagram tag used for 6LoWPAN frags or IPv6fragmentation.
TimeMilli mTimestamp; // The message timestamp.
uint16_t mReserved; // Number of reserved bytes (for header).
uint16_t mLength; // Current message length (number of bytes).
uint16_t mOffset; // A byte offset within the message.
uint16_t mMeshDest; // Used for unicast non-link-local messages.
uint16_t mPanId; // PAN ID (used for MLE Discover Request and Response).
uint8_t mChannel; // The message channel (used for MLE Announce).
RssAverager mRssAverager; // The averager maintaining the received signal strength (RSS) average.
#if OPENTHREAD_CONFIG_MLE_LINK_METRICS_SUBJECT_ENABLE
LqiAverager mLqiAverager; // The averager maintaining the Link quality indicator (LQI) average.
#endif
ChildMask mChildMask; // ChildMask to indicate which sleepy children need to receive this.
uint8_t mType : 3; // The message type.
uint8_t mSubType : 4; // The message sub type.
bool mDirectTx : 1; // Whether a direct transmission is required.
bool mLinkSecurity : 1; // Whether link security is enabled.
uint8_t mPriority : 2; // The message priority level (higher value is higher priority).
bool mInPriorityQ : 1; // Whether the message is queued in normal or priority queue.
bool mTxSuccess : 1; // Whether the direct tx of the message was successful.
bool mDoNotEvict : 1; // Whether this message may be evicted.
bool mMulticastLoop : 1; // Whether this multicast message may be looped back.
bool mResolvingAddress : 1; // Whether the message is pending an address query resolution.
#if OPENTHREAD_CONFIG_MULTI_RADIO
uint8_t mRadioType : 2; // The radio link type the message was received on, or should be sent on.
bool mIsRadioTypeSet : 1; // Whether the radio type is set.
static_assert(Mac::kNumRadioTypes <= (1 << 2), "mRadioType bitfield cannot store all radio type values");
#endif
#if OPENTHREAD_CONFIG_TIME_SYNC_ENABLE
bool mTimeSync : 1; // Whether the message is also used for time sync purpose.
int64_t mNetworkTimeOffset; // The time offset to the Thread network time, in microseconds.
uint8_t mTimeSyncSeq; // The time sync sequence.
#endif
};
static_assert(kBufferSize > sizeof(Metadata) + sizeof(otMessageBuffer), "Metadata does not fit in a single buffer");
static constexpr uint16_t kBufferDataSize = kBufferSize - sizeof(otMessageBuffer);
static constexpr uint16_t kHeadBufferDataSize = kBufferDataSize - sizeof(Metadata);
Metadata & GetMetadata(void) { return mBuffer.mHead.mMetadata; }
const Metadata &GetMetadata(void) const { return mBuffer.mHead.mMetadata; }
uint8_t * GetFirstData(void) { return mBuffer.mHead.mData; }
const uint8_t *GetFirstData(void) const { return mBuffer.mHead.mData; }
uint8_t * GetData(void) { return mBuffer.mData; }
const uint8_t *GetData(void) const { return mBuffer.mData; }
private:
union
{
struct
{
Metadata mMetadata;
uint8_t mData[kHeadBufferDataSize];
} mHead;
uint8_t mData[kBufferDataSize];
} mBuffer;
};
static_assert(sizeof(Buffer) >= kBufferSize, "Buffer size if not valid");
/**
* This class represents a message.
*
*/
class Message : public otMessage, public Buffer, public GetProvider<Message>
{
friend class Checksum;
friend class Crypto::HmacSha256;
friend class Crypto::Sha256;
friend class Crypto::AesCcm;
friend class MessagePool;
friend class MessageQueue;
friend class PriorityQueue;
public:
/**
* This enumeration represents the message type.
*
*/
enum Type : uint8_t
{
kTypeIp6 = 0, ///< A full uncompressed IPv6 packet
kType6lowpan = 1, ///< A 6lowpan frame
kTypeSupervision = 2, ///< A child supervision frame.
kTypeMacEmptyData = 3, ///< An empty MAC data frame.
kTypeOther = 4, ///< Other (data) message.
};
/**
* This enumeration represents the message sub-type.
*
*/
enum SubType : uint8_t
{
kSubTypeNone = 0, ///< None
kSubTypeMleAnnounce = 1, ///< MLE Announce
kSubTypeMleDiscoverRequest = 2, ///< MLE Discover Request
kSubTypeMleDiscoverResponse = 3, ///< MLE Discover Response
kSubTypeJoinerEntrust = 4, ///< Joiner Entrust
kSubTypeMplRetransmission = 5, ///< MPL next retransmission message
kSubTypeMleGeneral = 6, ///< General MLE
kSubTypeJoinerFinalizeResponse = 7, ///< Joiner Finalize Response
kSubTypeMleChildUpdateRequest = 8, ///< MLE Child Update Request
kSubTypeMleDataResponse = 9, ///< MLE Data Response
kSubTypeMleChildIdRequest = 10, ///< MLE Child ID Request
kSubTypeMleDataRequest = 11, ///< MLE Data Request
};
enum Priority : uint8_t
{
kPriorityLow = OT_MESSAGE_PRIORITY_LOW, ///< Low priority level.
kPriorityNormal = OT_MESSAGE_PRIORITY_NORMAL, ///< Normal priority level.
kPriorityHigh = OT_MESSAGE_PRIORITY_HIGH, ///< High priority level.
kPriorityNet = OT_MESSAGE_PRIORITY_HIGH + 1, ///< Network Control priority level.
};
static constexpr uint8_t kNumPriorities = 4; ///< Number of priority levels.
/**
* This enumeration represents the link security mode (used by `Settings` constructor).
*
*/
enum LinkSecurityMode : bool
{
kNoLinkSecurity = false, ///< Link security disabled (no link security).
kWithLinkSecurity = true, ///< Link security enabled.
};
/**
* This enumeration represents the message ownership model when a `Message` instance is passed to a method/function.
*
*/
enum Ownership : uint8_t
{
/**
* This value indicates that the method/function receiving a `Message` instance should take custody of the
* message (e.g., the method should `Free()` the message if no longer needed).
*
*/
kTakeCustody,
/**
* This value indicates that the method/function receiving a `Message` instance does not own the message (e.g.,
* it should not `Free()` or `Enqueue()` it in a queue). The receiving method/function should create a
* copy/clone of the message to keep (if/when needed).
*
*/
kCopyToUse,
};
/**
* This class represents settings used for creating a new message.
*
*/
class Settings : public otMessageSettings
{
public:
/**
* This constructor initializes the `Settings` object.
*
* @param[in] aSecurityMode A link security mode.
* @param[in] aPriority A message priority.
*
*/
Settings(LinkSecurityMode aSecurityMode, Priority aPriority);
/**
* This constructor initializes the `Settings` with a given message priority and link security enabled.
*
* @param[in] aPriority A message priority.
*
*/
explicit Settings(Priority aPriority)
: Settings(kWithLinkSecurity, aPriority)
{
}
/**
* This method gets the message priority.
*
* @returns The message priority.
*
*/
Priority GetPriority(void) const { return static_cast<Priority>(mPriority); }
/**
* This method indicates whether the link security should be enabled.
*
* @returns TRUE if link security should be enabled, FALSE otherwise.
*
*/
bool IsLinkSecurityEnabled(void) const { return mLinkSecurityEnabled; }
/**
* This static method converts a pointer to an `otMessageSettings` to a `Settings`.
*
* @param[in] aSettings A pointer to `otMessageSettings` to covert from.
* If it is `nullptr`, then the default settings `GetDefault()` will be used.
*
* @returns A reference to the converted `Settings` or the default if @p aSettings is `nullptr`.
*
*/
static const Settings &From(const otMessageSettings *aSettings);
/**
* This static method returns the default settings with link security enabled and `kPriorityNormal` priority.
*
* @returns A reference to the default settings (link security enable and `kPriorityNormal` priority).
*
*/
static const Settings &GetDefault(void) { return static_cast<const Settings &>(kDefault); }
private:
static const otMessageSettings kDefault;
};
/**
* This method returns a reference to the OpenThread Instance which owns the `Message`.
*
* @returns A reference to the `Instance`.
*
*/
Instance &GetInstance(void) const;
/**
* This method frees this message buffer.
*
*/
void Free(void);
/**
* This method returns a pointer to the next message.
*
* @returns A pointer to the next message in the list or `nullptr` if at the end of the list.
*
*/
Message *GetNext(void) const;
/**
* This method returns the number of bytes in the message.
*
* @returns The number of bytes in the message.
*
*/
uint16_t GetLength(void) const { return GetMetadata().mLength; }
/**
* This method sets the number of bytes in the message.
*
* @param[in] aLength Requested number of bytes in the message.
*
* @retval kErrorNone Successfully set the length of the message.
* @retval kErrorNoBufs Failed to grow the size of the message because insufficient buffers were available.
*
*/
Error SetLength(uint16_t aLength);
/**
* This method returns the number of buffers in the message.
*
*/
uint8_t GetBufferCount(void) const;
/**
* This method returns the byte offset within the message.
*
* @returns A byte offset within the message.
*
*/
uint16_t GetOffset(void) const { return GetMetadata().mOffset; }
/**
* This method moves the byte offset within the message.
*
* @param[in] aDelta The number of bytes to move the current offset, which may be positive or negative.
*
*/
void MoveOffset(int aDelta);
/**
* This method sets the byte offset within the message.
*
* @param[in] aOffset The byte offset within the message.
*
*/
void SetOffset(uint16_t aOffset);
/**
* This method returns the type of the message.
*
* @returns The type of the message.
*
*/
Type GetType(void) const { return static_cast<Type>(GetMetadata().mType); }
/**
* This method sets the message type.
*
* @param[in] aType The message type.
*
*/
void SetType(Type aType) { GetMetadata().mType = aType; }
/**
* This method returns the sub type of the message.
*
* @returns The sub type of the message.
*
*/
SubType GetSubType(void) const { return static_cast<SubType>(GetMetadata().mSubType); }
/**
* This method sets the message sub type.
*
* @param[in] aSubType The message sub type.
*
*/
void SetSubType(SubType aSubType) { GetMetadata().mSubType = aSubType; }
/**
* This method returns whether or not the message is of MLE subtype.
*
* @retval TRUE If message is of MLE subtype.
* @retval FALSE If message is not of MLE subtype.
*
*/
bool IsSubTypeMle(void) const;
/**
* This method checks whether this multicast message may be looped back.
*
* @retval TRUE If message may be looped back.
* @retval FALSE If message must not be looped back.
*
*/
bool GetMulticastLoop(void) const { return GetMetadata().mMulticastLoop; }
/**
* This method sets whether multicast may be looped back.
*
* @param[in] aMulticastLoop Whether allow looping back multicast.
*
*/
void SetMulticastLoop(bool aMulticastLoop) { GetMetadata().mMulticastLoop = aMulticastLoop; }
/**
* This method returns the message priority level.
*
* @returns The priority level associated with this message.
*
*/
Priority GetPriority(void) const { return static_cast<Priority>(GetMetadata().mPriority); }
/**
* This method sets the messages priority.
* If the message is already queued in a priority queue, changing the priority ensures to
* update the message in the associated queue.
*
* @param[in] aPriority The message priority level.
*
* @retval kErrorNone Successfully set the priority for the message.
* @retval kErrorInvalidArgs Priority level is not invalid.
*
*/
Error SetPriority(Priority aPriority);
/**
* This static method convert a `Priority` to a string.
*
* @param[in] aPriority The priority level.
*
* @returns A string representation of @p aPriority.
*
*/
static const char *PriorityToString(Priority aPriority);
/**
* This method prepends bytes to the front of the message.
*
* On success, this method grows the message by @p aLength bytes.
*
* @param[in] aBuf A pointer to a data buffer (can be `nullptr` to grow message without writing bytes).
* @param[in] aLength The number of bytes to prepend.
*
* @retval kErrorNone Successfully prepended the bytes.
* @retval kErrorNoBufs Not enough reserved bytes in the message.
*
*/
Error PrependBytes(const void *aBuf, uint16_t aLength);
/**
* This method prepends an object to the front of the message.
*
* On success, this method grows the message by the size of the object.
*
* @tparam ObjectType The object type to prepend to the message.
*
* @param[in] aObject A reference to the object to prepend to the message.
*
* @retval kErrorNone Successfully prepended the object.
* @retval kErrorNoBufs Not enough reserved bytes in the message.
*
*/
template <typename ObjectType> Error Prepend(const ObjectType &aObject)
{
static_assert(!TypeTraits::IsPointer<ObjectType>::kValue, "ObjectType must not be a pointer");
return PrependBytes(&aObject, sizeof(ObjectType));
}
/**
* This method removes header bytes from the message.
*
* @param[in] aLength Number of header bytes to remove.
*
*/
void RemoveHeader(uint16_t aLength);
/**
* This method appends bytes to the end of the message.
*
* On success, this method grows the message by @p aLength bytes.
*
* @param[in] aBuf A pointer to a data buffer (MUST not be `nullptr`).
* @param[in] aLength The number of bytes to append.
*
* @retval kErrorNone Successfully appended the bytes.
* @retval kErrorNoBufs Insufficient available buffers to grow the message.
*
*/
Error AppendBytes(const void *aBuf, uint16_t aLength);
/**
* This method appends bytes read from another or potentially the same message to the end of the current message.
*
* On success, this method grows the message by @p aLength bytes.
*
* @param[in] aMessage The message to read the bytes from (it can be the same as the current message).
* @param[in] aOffset The offset in @p aMessage to start reading the bytes from.
* @param[in] aLength The number of bytes to read from @p aMessage and append.
*
* @retval kErrorNone Successfully appended the bytes.
* @retval kErrorNoBufs Insufficient available buffers to grow the message.
* @retval kErrorParse Not enough bytes in @p aMessage to read @p aLength bytes from @p aOffset.
*
*/
Error AppendBytesFromMessage(const Message &aMessage, uint16_t aOffset, uint16_t aLength);
/**
* This method appends an object to the end of the message.
*
* On success, this method grows the message by the size of the appended object
*
* @tparam ObjectType The object type to append to the message.
*
* @param[in] aObject A reference to the object to append to the message.
*
* @retval kErrorNone Successfully appended the object.
* @retval kErrorNoBufs Insufficient available buffers to grow the message.
*
*/
template <typename ObjectType> Error Append(const ObjectType &aObject)
{
static_assert(!TypeTraits::IsPointer<ObjectType>::kValue, "ObjectType must not be a pointer");
return AppendBytes(&aObject, sizeof(ObjectType));
}
/**
* This method reads bytes from the message.
*
* @param[in] aOffset Byte offset within the message to begin reading.
* @param[out] aBuf A pointer to a data buffer to copy the read bytes into.
* @param[in] aLength Number of bytes to read.
*
* @returns The number of bytes read.
*
*/
uint16_t ReadBytes(uint16_t aOffset, void *aBuf, uint16_t aLength) const;
/**
* This method reads a given number of bytes from the message.
*
* If there are fewer bytes available in the message than the requested read length, the available bytes will be
* read and copied into @p aBuf. In this case `kErrorParse` will be returned.
*
* @param[in] aOffset Byte offset within the message to begin reading.
* @param[out] aBuf A pointer to a data buffer to copy the read bytes into.
* @param[in] aLength Number of bytes to read.
*
* @retval kErrorNone @p aLength bytes were successfully read from message.
* @retval kErrorParse Not enough bytes remaining in message to read the entire object.
*
*/
Error Read(uint16_t aOffset, void *aBuf, uint16_t aLength) const;
/**
* This method reads an object from the message.
*
* If there are fewer bytes available in the message than the requested object size, the available bytes will be
* read and copied into @p aObject (@p aObject will be read partially). In this case `kErrorParse` will
* be returned.
*
* @tparam ObjectType The object type to read from the message.
*
* @param[in] aOffset Byte offset within the message to begin reading.
* @param[out] aObject A reference to the object to read into.
*
* @retval kErrorNone Object @p aObject was successfully read from message.
* @retval kErrorParse Not enough bytes remaining in message to read the entire object.
*
*/
template <typename ObjectType> Error Read(uint16_t aOffset, ObjectType &aObject) const
{
static_assert(!TypeTraits::IsPointer<ObjectType>::kValue, "ObjectType must not be a pointer");
return Read(aOffset, &aObject, sizeof(ObjectType));
}
/**
* This method compares the bytes in the message at a given offset with a given byte array.
*
* If there are fewer bytes available in the message than the requested @p aLength, the comparison is treated as
* failure (returns FALSE).
*
* @param[in] aOffset Byte offset within the message to read from for the comparison.
* @param[in] aBuf A pointer to a data buffer to compare with the bytes from message.
* @param[in] aLength Number of bytes in @p aBuf.
* @param[in] aMatcher A `ByteMatcher` function pointer to match the bytes. If `nullptr` then bytes are directly
* compared.
*
* @returns TRUE if there are enough bytes available in @p aMessage and they match the bytes from @p aBuf,
* FALSE otherwise.
*
*/
bool CompareBytes(uint16_t aOffset, const void *aBuf, uint16_t aLength, ByteMatcher aMatcher = nullptr) const;
/**
* This method compares the bytes in the message at a given offset with bytes read from another message.
*
* If either message has fewer bytes available than the requested @p aLength, the comparison is treated as failure
* (returns FALSE).
*
* @param[in] aOffset Byte offset within the message to read from for the comparison.
* @param[in] aOtherMessage The other message to compare with.
* @param[in] aOtherOffset Byte offset within @p aOtherMessage to read from for the comparison.
* @param[in] aLength Number of bytes to compare.
* @param[in] aMatcher A `ByteMatcher` function pointer to match the bytes. If `nullptr` then bytes are
* directly compared.
*
* @returns TRUE if there are enough bytes available in both messages and they all match. FALSE otherwise.
*
*/
bool CompareBytes(uint16_t aOffset,
const Message &aOtherMessage,
uint16_t aOtherOffset,
uint16_t aLength,
ByteMatcher aMatcher = nullptr) const;
/**
* This method compares the bytes in the message at a given offset with an object.
*
* The bytes in the message are compared with the bytes in @p aObject. If there are fewer bytes available in the
* message than the requested object size, it is treated as failed comparison (returns FALSE).
*
* @tparam ObjectType The object type to compare with the bytes in message.
*
* @param[in] aOffset Byte offset within the message to read from for the comparison.
* @param[in] aObject A reference to the object to compare with the message bytes.
*
* @returns TRUE if there are enough bytes available in @p aMessage and they match the bytes in @p aObject,
* FALSE otherwise.
*
*/
template <typename ObjectType> bool Compare(uint16_t aOffset, const ObjectType &aObject) const
{
static_assert(!TypeTraits::IsPointer<ObjectType>::kValue, "ObjectType must not be a pointer");
return CompareBytes(aOffset, &aObject, sizeof(ObjectType));
}
/**
* This method writes bytes to the message.
*
* This method will not resize the message. The given data to write (with @p aLength bytes) MUST fit within the
* existing message buffer (from the given offset @p aOffset up to the message's length).
*
* @param[in] aOffset Byte offset within the message to begin writing.
* @param[in] aBuf A pointer to a data buffer.
* @param[in] aLength Number of bytes to write.
*
*/
void WriteBytes(uint16_t aOffset, const void *aBuf, uint16_t aLength);
/**
* This methods writes an object to the message.
*
* This method will not resize the message. The entire given object (all its bytes) MUST fit within the existing
* message buffer (from the given offset @p aOffset up to the message's length).
*
* @tparam ObjectType The object type to write to the message.
*
* @param[in] aOffset Byte offset within the message to begin writing.
* @param[in] aObject A reference to the object to write.
*
*/
template <typename ObjectType> void Write(uint16_t aOffset, const ObjectType &aObject)
{
static_assert(!TypeTraits::IsPointer<ObjectType>::kValue, "ObjectType must not be a pointer");
WriteBytes(aOffset, &aObject, sizeof(ObjectType));
}
/**
* This method copies bytes from one message to another.
*
* If source and destination messages are the same, `CopyTo()` can be used to perform a backward copy, but
* it MUST not be used to forward copy within the same message (i.e., when source and destination messages are the
* same and source offset is smaller than the destination offset).
*
* @param[in] aSourceOffset Byte offset within the source message to begin reading.
* @param[in] aDestinationOffset Byte offset within the destination message to begin writing.
* @param[in] aLength Number of bytes to copy.
* @param[in] aMessage Message to copy to.
*
* @returns The number of bytes copied.
*
*/
uint16_t CopyTo(uint16_t aSourceOffset, uint16_t aDestinationOffset, uint16_t aLength, Message &aMessage) const;
/**
* This method creates a copy of the message.
*
* It allocates the new message from the same message pool as the original one and copies @p aLength octets
* of the payload. The `Type`, `SubType`, `LinkSecurity`, `Offset`, `InterfaceId`, and `Priority` fields on the
* cloned message are also copied from the original one.
*
* @param[in] aLength Number of payload bytes to copy.
*
* @returns A pointer to the message or nullptr if insufficient message buffers are available.
*
*/
Message *Clone(uint16_t aLength) const;
/**
* This method creates a copy of the message.
*
* It allocates the new message from the same message pool as the original one and copies the entire payload. The
* `Type`, `SubType`, `LinkSecurity`, `Offset`, `InterfaceId`, and `Priority` fields on the cloned message are also
* copied from the original one.
*
* @returns A pointer to the message or `nullptr` if insufficient message buffers are available.
*
*/
Message *Clone(void) const { return Clone(GetLength()); }
/**
* This method returns the datagram tag used for 6LoWPAN fragmentation or the identification used for IPv6
* fragmentation.
*
* @returns The 6LoWPAN datagram tag or the IPv6 fragment identification.
*
*/
uint32_t GetDatagramTag(void) const { return GetMetadata().mDatagramTag; }
/**
* This method sets the datagram tag used for 6LoWPAN fragmentation.
*
* @param[in] aTag The 6LoWPAN datagram tag.
*
*/
void SetDatagramTag(uint32_t aTag) { GetMetadata().mDatagramTag = aTag; }
/**
* This method returns whether or not the message forwarding is scheduled for the child.
*
* @param[in] aChildIndex The index into the child table.
*
* @retval TRUE If the message is scheduled to be forwarded to the child.
* @retval FALSE If the message is not scheduled to be forwarded to the child.
*
*/
bool GetChildMask(uint16_t aChildIndex) const;
/**
* This method unschedules forwarding of the message to the child.
*
* @param[in] aChildIndex The index into the child table.
*
*/
void ClearChildMask(uint16_t aChildIndex);
/**
* This method schedules forwarding of the message to the child.
*
* @param[in] aChildIndex The index into the child table.
*
*/
void SetChildMask(uint16_t aChildIndex);
/**
* This method returns whether or not the message forwarding is scheduled for at least one child.
*
* @retval TRUE If message forwarding is scheduled for at least one child.
* @retval FALSE If message forwarding is not scheduled for any child.
*
*/
bool IsChildPending(void) const;
/**
* This method returns the RLOC16 of the mesh destination.
*
* @note Only use this for non-link-local unicast messages.
*
* @returns The IEEE 802.15.4 Destination PAN ID.
*
*/
uint16_t GetMeshDest(void) const { return GetMetadata().mMeshDest; }
/**
* This method sets the RLOC16 of the mesh destination.
*
* @note Only use this when sending non-link-local unicast messages.
*
* @param[in] aMeshDest The IEEE 802.15.4 Destination PAN ID.
*
*/
void SetMeshDest(uint16_t aMeshDest) { GetMetadata().mMeshDest = aMeshDest; }
/**
* This method returns the IEEE 802.15.4 Destination PAN ID.
*
* @note Only use this when sending MLE Discover Request or Response messages.
*
* @returns The IEEE 802.15.4 Destination PAN ID.
*
*/
uint16_t GetPanId(void) const { return GetMetadata().mPanId; }
/**
* This method sets the IEEE 802.15.4 Destination PAN ID.
*
* @note Only use this when sending MLE Discover Request or Response messages.
*
* @param[in] aPanId The IEEE 802.15.4 Destination PAN ID.
*
*/
void SetPanId(uint16_t aPanId) { GetMetadata().mPanId = aPanId; }
/**
* This method returns the IEEE 802.15.4 Channel to use for transmission.
*
* @note Only use this when sending MLE Announce messages.
*
* @returns The IEEE 802.15.4 Channel to use for transmission.
*
*/
uint8_t GetChannel(void) const { return GetMetadata().mChannel; }
/**
* This method sets the IEEE 802.15.4 Channel to use for transmission.
*
* @note Only use this when sending MLE Announce messages.
*
* @param[in] aChannel The IEEE 802.15.4 Channel to use for transmission.
*
*/
void SetChannel(uint8_t aChannel) { GetMetadata().mChannel = aChannel; }
/**
* This method returns the message timestamp.
*
* @returns The message timestamp.
*
*/
TimeMilli GetTimestamp(void) const { return GetMetadata().mTimestamp; }
/**
* This method sets the message timestamp to a given time.
*
* @param[in] aTimestamp The timestamp value.
*
*/
void SetTimestamp(TimeMilli aTimestamp) { GetMetadata().mTimestamp = aTimestamp; }
/**
* This method sets the message timestamp to the current time.
*
*/
void SetTimestampToNow(void) { SetTimestamp(TimerMilli::GetNow()); }
/**
* This method returns whether or not message forwarding is scheduled for direct transmission.
*
* @retval TRUE If message forwarding is scheduled for direct transmission.
* @retval FALSE If message forwarding is not scheduled for direct transmission.
*
*/
bool IsDirectTransmission(void) const { return GetMetadata().mDirectTx; }
/**
* This method unschedules forwarding using direct transmission.
*
*/
void ClearDirectTransmission(void) { GetMetadata().mDirectTx = false; }
/**
* This method schedules forwarding using direct transmission.
*
*/
void SetDirectTransmission(void) { GetMetadata().mDirectTx = true; }
/**
* This method indicates whether the direct transmission of message was successful.
*
* @retval TRUE If direct transmission of message was successful (all fragments were delivered and acked).
* @retval FALSE If direct transmission of message failed (at least one fragment failed).
*
*/
bool GetTxSuccess(void) const { return GetMetadata().mTxSuccess; }
/**
* This method sets whether the direct transmission of message was successful.
*
* @param[in] aTxSuccess TRUE if the direct transmission is successful, FALSE otherwise (i.e., at least one
* fragment transmission failed).
*
*/
void SetTxSuccess(bool aTxSuccess) { GetMetadata().mTxSuccess = aTxSuccess; }
/**
* This method indicates whether the message may be evicted.
*
* @retval TRUE If the message must not be evicted.
* @retval FALSE If the message may be evicted.
*
*/
bool GetDoNotEvict(void) const { return GetMetadata().mDoNotEvict; }
/**
* This method sets whether the message may be evicted.
*
* @param[in] aDoNotEvict TRUE if the message may not be evicted, FALSE otherwise.
*
*/
void SetDoNotEvict(bool aDoNotEvict) { GetMetadata().mDoNotEvict = aDoNotEvict; }
/**
* This method indicates whether the message is waiting for an address query resolution.
*
* @retval TRUE If the message is waiting for address query resolution.
* @retval FALSE If the message is not waiting for address query resolution.
*
*/
bool IsResolvingAddress(void) const { return GetMetadata().mResolvingAddress; }
/**
* This method sets whether the message is waiting for an address query resolution.
*
* @param[in] aResolvingAddress TRUE if message is waiting for address resolution, FALSE otherwise.
*
*/
void SetResolvingAddress(bool aResolvingAddress) { GetMetadata().mResolvingAddress = aResolvingAddress; }
/**
* This method indicates whether or not link security is enabled for the message.
*
* @retval TRUE If link security is enabled.
* @retval FALSE If link security is not enabled.
*
*/
bool IsLinkSecurityEnabled(void) const { return GetMetadata().mLinkSecurity; }
/**
* This method sets whether or not link security is enabled for the message.
*
* @param[in] aEnabled TRUE if link security is enabled, FALSE otherwise.
*
*/
void SetLinkSecurityEnabled(bool aEnabled) { GetMetadata().mLinkSecurity = aEnabled; }
/**
* This method updates the average RSS (Received Signal Strength) associated with the message by adding the given
* RSS value to the average. Note that a message can be composed of multiple 802.15.4 data frame fragments each
* received with a different signal strength.
*
* @param[in] aRss A new RSS value (in dBm) to be added to average.
*
*/
void AddRss(int8_t aRss) { IgnoreError(GetMetadata().mRssAverager.Add(aRss)); }
/**
* This method returns the average RSS (Received Signal Strength) associated with the message.
*
* @returns The current average RSS value (in dBm) or OT_RADIO_RSSI_INVALID if no average is available.
*
*/
int8_t GetAverageRss(void) const { return GetMetadata().mRssAverager.GetAverage(); }
/**
* This method returns a const reference to RssAverager of the message.
*
* @returns A const reference to the RssAverager of the message.
*
*/
const RssAverager &GetRssAverager(void) const { return GetMetadata().mRssAverager; }
#if OPENTHREAD_CONFIG_MLE_LINK_METRICS_SUBJECT_ENABLE
/**
* This method updates the average LQI (Link Quality Indicator) associated with the message.
*
* The given LQI value would be added to the average. Note that a message can be composed of multiple 802.15.4
* frame fragments each received with a different signal strength.
*
* @param[in] aLqi A new LQI value (has no unit) to be added to average.
*
*/
void AddLqi(uint8_t aLqi) { GetMetadata().mLqiAverager.Add(aLqi); }
/**
* This method returns the average LQI (Link Quality Indicator) associated with the message.
*
* @returns The current average LQI value (in dBm) or OT_RADIO_LQI_NONE if no average is available.
*
*/
uint8_t GetAverageLqi(void) const { return GetMetadata().mLqiAverager.GetAverage(); }
/**
* This method returns the count of frames counted so far.
*
* @returns The count of frames that have been counted.
*
*/
uint8_t GetPsduCount(void) const { return GetMetadata().mLqiAverager.GetCount(); }
#endif
/**
* This method sets the message's link info properties (PAN ID, link security, RSS) from a given `ThreadLinkInfo`.
*
* @param[in] aLinkInfo The `ThreadLinkInfo` instance from which to set message's related properties.
*
*/
void SetLinkInfo(const ThreadLinkInfo &aLinkInfo);
/**
* This method returns a pointer to the message queue (if any) where this message is queued.
*
* @returns A pointer to the message queue or `nullptr` if not in any message queue.
*
*/
MessageQueue *GetMessageQueue(void) const
{
return !GetMetadata().mInPriorityQ ? static_cast<MessageQueue *>(GetMetadata().mQueue) : nullptr;
}
/**
* This method returns a pointer to the priority message queue (if any) where this message is queued.
*
* @returns A pointer to the priority queue or `nullptr` if not in any priority queue.
*
*/
PriorityQueue *GetPriorityQueue(void) const
{
return GetMetadata().mInPriorityQ ? static_cast<PriorityQueue *>(GetMetadata().mQueue) : nullptr;
}
/**
* This method indicates whether or not the message is also used for time sync purpose.
*
* When OPENTHREAD_CONFIG_TIME_SYNC_ENABLE is 0, this method always return false.
*
* @retval TRUE If the message is also used for time sync purpose.
* @retval FALSE If the message is not used for time sync purpose.
*
*/
bool IsTimeSync(void) const;
#if OPENTHREAD_CONFIG_TIME_SYNC_ENABLE
/**
* This method sets whether or not the message is also used for time sync purpose.
*
* @param[in] aEnabled TRUE if the message is also used for time sync purpose, FALSE otherwise.
*
*/
void SetTimeSync(bool aEnabled) { GetMetadata().mTimeSync = aEnabled; }
/**
* This method sets the offset to network time.
*
* @param[in] aNetworkTimeOffset The offset to network time.
*
*/
void SetNetworkTimeOffset(int64_t aNetworkTimeOffset) { GetMetadata().mNetworkTimeOffset = aNetworkTimeOffset; }
/**
* This method gets the offset to network time.
*
* @returns The offset to network time.
*
*/
int64_t GetNetworkTimeOffset(void) const { return GetMetadata().mNetworkTimeOffset; }
/**
* This method sets the time sync sequence.
*
* @param[in] aTimeSyncSeq The time sync sequence.
*
*/
void SetTimeSyncSeq(uint8_t aTimeSyncSeq) { GetMetadata().mTimeSyncSeq = aTimeSyncSeq; }
/**
* This method gets the time sync sequence.
*
* @returns The time sync sequence.
*
*/
uint8_t GetTimeSyncSeq(void) const { return GetMetadata().mTimeSyncSeq; }
#endif // OPENTHREAD_CONFIG_TIME_SYNC_ENABLE
#if OPENTHREAD_CONFIG_MULTI_RADIO
/**
* This method indicates whether the radio type is set.
*
* @retval TRUE If the radio type is set.
* @retval FALSE If the radio type is not set.
*
*/
bool IsRadioTypeSet(void) const { return GetMetadata().mIsRadioTypeSet; }
/**
* This method gets the radio link type the message was received on, or should be sent on.
*
* This method should be used only when `IsRadioTypeSet()` returns `true`.
*
* @returns The radio link type of the message.
*
*/
Mac::RadioType GetRadioType(void) const { return static_cast<Mac::RadioType>(GetMetadata().mRadioType); }
/**
* This method sets the radio link type the message was received on, or should be sent on.
*
* @param[in] aRadioType A radio link type of the message.
*
*/
void SetRadioType(Mac::RadioType aRadioType)
{
GetMetadata().mIsRadioTypeSet = true;
GetMetadata().mRadioType = aRadioType;
}
/**
* This method clears any previously set radio type on the message.
*
* After calling this method, `IsRadioTypeSet()` returns false until radio type is set (`SetRadioType()`).
*
*/
void ClearRadioType(void) { GetMetadata().mIsRadioTypeSet = false; }
#endif // #if OPENTHREAD_CONFIG_MULTI_RADIO
protected:
class ConstIterator : public ItemPtrIterator<const Message, ConstIterator>
{
friend class ItemPtrIterator<const Message, ConstIterator>;
public:
ConstIterator(void) = default;
explicit ConstIterator(const Message *aMessage)
: ItemPtrIterator(aMessage)
{
}
private:
void Advance(void) { mItem = mItem->GetNext(); }
};
class Iterator : public ItemPtrIterator<Message, Iterator>
{
friend class ItemPtrIterator<Message, Iterator>;
public:
Iterator(void)
: mNext(nullptr)
{
}
explicit Iterator(Message *aMessage)
: ItemPtrIterator(aMessage)
, mNext(NextMessage(aMessage))
{
}
private:
void Advance(void);
static Message *NextMessage(Message *aMessage) { return (aMessage != nullptr) ? aMessage->GetNext() : nullptr; }
Message *mNext;
};
uint16_t GetReserved(void) const { return GetMetadata().mReserved; }
void SetReserved(uint16_t aReservedHeader) { GetMetadata().mReserved = aReservedHeader; }
private:
class Chunk : public Data<kWithUint16Length>
{
public:
const Buffer *GetBuffer(void) const { return mBuffer; }
void SetBuffer(const Buffer *aBuffer) { mBuffer = aBuffer; }
private:
const Buffer *mBuffer; // Buffer containing the chunk
};
class MutableChunk : public Chunk
{
public:
uint8_t *GetBytes(void) { return AsNonConst(Chunk::GetBytes()); }
};
void GetFirstChunk(uint16_t aOffset, uint16_t &aLength, Chunk &aChunk) const;
void GetNextChunk(uint16_t &aLength, Chunk &aChunk) const;
void GetFirstChunk(uint16_t aOffset, uint16_t &aLength, MutableChunk &aChunk)
{
AsConst(this)->GetFirstChunk(aOffset, aLength, static_cast<Chunk &>(aChunk));
}
void GetNextChunk(uint16_t &aLength, MutableChunk &aChunk)
{
AsConst(this)->GetNextChunk(aLength, static_cast<Chunk &>(aChunk));
}
MessagePool *GetMessagePool(void) const { return GetMetadata().mMessagePool; }
void SetMessagePool(MessagePool *aMessagePool) { GetMetadata().mMessagePool = aMessagePool; }
bool IsInAQueue(void) const { return (GetMetadata().mQueue != nullptr); }
void SetMessageQueue(MessageQueue *aMessageQueue);
void SetPriorityQueue(PriorityQueue *aPriorityQueue);
Message *& Next(void) { return GetMetadata().mNext; }
Message *const &Next(void) const { return GetMetadata().mNext; }
Message *& Prev(void) { return GetMetadata().mPrev; }
static Message * NextOf(Message *aMessage) { return (aMessage != nullptr) ? aMessage->Next() : nullptr; }
static const Message *NextOf(const Message *aMessage) { return (aMessage != nullptr) ? aMessage->Next() : nullptr; }
Error ResizeMessage(uint16_t aLength);
};
/**
* This class implements a message queue.
*
*/
class MessageQueue : public otMessageQueue
{
friend class Message;
friend class PriorityQueue;
public:
typedef otMessageQueueInfo Info; ///< This struct represents info (number of messages/buffers) about a queue.
/**
* This enumeration represents a position (head or tail) in the queue. This is used to specify where a new message
* should be added in the queue.
*
*/
enum QueuePosition : uint8_t
{
kQueuePositionHead, ///< Indicates the head (front) of the list.
kQueuePositionTail, ///< Indicates the tail (end) of the list.
};
/**
* This constructor initializes the message queue.
*
*/
MessageQueue(void) { SetTail(nullptr); }
/**
* This method returns a pointer to the first message.
*
* @returns A pointer to the first message.
*
*/
Message *GetHead(void) { return Message::NextOf(GetTail()); }
/**
* This method returns a pointer to the first message.
*
* @returns A pointer to the first message.
*
*/
const Message *GetHead(void) const { return Message::NextOf(GetTail()); }
/**
* This method adds a message to the end of the list.
*
* @param[in] aMessage The message to add.
*
*/
void Enqueue(Message &aMessage) { Enqueue(aMessage, kQueuePositionTail); }
/**
* This method adds a message at a given position (head/tail) of the list.
*
* @param[in] aMessage The message to add.
* @param[in] aPosition The position (head or tail) where to add the message.
*
*/
void Enqueue(Message &aMessage, QueuePosition aPosition);
/**
* This method removes a message from the list.
*
* @param[in] aMessage The message to remove.
*
*/
void Dequeue(Message &aMessage);
/**
* This method removes a message from the queue and frees it.
*
* @param[in] aMessage The message to remove and free.
*
*/
void DequeueAndFree(Message &aMessage);
/**
* This method removes and frees all messages from the queue.
*
*/
void DequeueAndFreeAll(void);
/**
* This method gets the information about number of messages and buffers in the queue.
*
* This method updates `aInfo` and adds number of message/buffers in the message queue to the corresponding member
* variable in `aInfo`. The caller needs to make sure `aInfo` is initialized before calling this method (e.g.,
* clearing `aInfo`). Same `aInfo` can be passed in multiple calls of `GetInfo(aInfo)` on different queues to add
* up the number of messages/buffers on different queues.
*
* @param[out] aInfo A reference to `Info` structure to update.ni
*
*/
void GetInfo(Info &aInfo) const;
// The following methods are intended to support range-based `for`
// loop iteration over the queue entries and should not be used
// directly. The range-based `for` works correctly even if the
// current entry is removed from the queue during iteration.
Message::Iterator begin(void);
Message::Iterator end(void) { return Message::Iterator(); }
Message::ConstIterator begin(void) const;
Message::ConstIterator end(void) const { return Message::ConstIterator(); }
private:
Message * GetTail(void) { return static_cast<Message *>(mData); }
const Message *GetTail(void) const { return static_cast<const Message *>(mData); }
void SetTail(Message *aMessage) { mData = aMessage; }
};
/**
* This class implements a priority queue.
*
*/
class PriorityQueue : private Clearable<PriorityQueue>
{
friend class Message;
friend class MessageQueue;
friend class MessagePool;
public:
typedef otMessageQueueInfo Info; ///< This struct represents info (number of messages/buffers) about a queue.
/**
* This constructor initializes the priority queue.
*
*/
PriorityQueue(void) { Clear(); }
/**
* This method returns a pointer to the first message.
*
* @returns A pointer to the first message.
*
*/
Message *GetHead(void) { return AsNonConst(AsConst(this)->GetHead()); }
/**
* This method returns a pointer to the first message.
*
* @returns A pointer to the first message.
*
*/
const Message *GetHead(void) const;
/**
* This method returns a pointer to the first message for a given priority level.
*
* @param[in] aPriority Priority level.
*
* @returns A pointer to the first message with given priority level or `nullptr` if there is no messages with
* this priority level.
*
*/
Message *GetHeadForPriority(Message::Priority aPriority)
{
return AsNonConst(AsConst(this)->GetHeadForPriority(aPriority));
}
/**
* This method returns a pointer to the first message for a given priority level.
*
* @param[in] aPriority Priority level.
*
* @returns A pointer to the first message with given priority level or `nullptr` if there is no messages with
* this priority level.
*
*/
const Message *GetHeadForPriority(Message::Priority aPriority) const;
/**
* This method adds a message to the queue.
*
* @param[in] aMessage The message to add.
*
*/
void Enqueue(Message &aMessage);
/**
* This method removes a message from the list.
*
* @param[in] aMessage The message to remove.
*
*/
void Dequeue(Message &aMessage);
/**
* This method removes a message from the queue and frees it.
*
* @param[in] aMessage The message to remove and free.
*
*/
void DequeueAndFree(Message &aMessage);
/**
* This method removes and frees all messages from the queue.
*
*/
void DequeueAndFreeAll(void);
/**
* This method returns the tail of the list (last message in the list).
*
* @returns A pointer to the tail of the list.
*
*/
Message *GetTail(void) { return AsNonConst(AsConst(this)->GetTail()); }
/**
* This method returns the tail of the list (last message in the list).
*
* @returns A pointer to the tail of the list.
*
*/
const Message *GetTail(void) const;
/**
* This method gets the information about number of messages and buffers in the priority queue.
*
* This method updates `aInfo` array and adds number of message/buffers in the message queue to the corresponding
* member variable in `aInfo`. The caller needs to make sure `aInfo` is initialized before calling this method
* (e.g., clearing `aInfo`). Same `aInfo` can be passed in multiple calls of `GetInfo(aInfo)` on different queues
* to add up the number of messages/buffers on different queues.
*
* @param[out] aInfo A reference to an `Info` structure to update.
*
*/
void GetInfo(Info &aInfo) const;
// The following methods are intended to support range-based `for`
// loop iteration over the queue entries and should not be used
// directly. The range-based `for` works correctly even if the
// current entry is removed from the queue during iteration.
Message::Iterator begin(void);
Message::Iterator end(void) { return Message::Iterator(); }
Message::ConstIterator begin(void) const;
Message::ConstIterator end(void) const { return Message::ConstIterator(); }
private:
uint8_t PrevPriority(uint8_t aPriority) const
{
return (aPriority == Message::kNumPriorities - 1) ? 0 : (aPriority + 1);
}
const Message *FindFirstNonNullTail(Message::Priority aStartPriorityLevel) const;
Message *FindFirstNonNullTail(Message::Priority aStartPriorityLevel)
{
return AsNonConst(AsConst(this)->FindFirstNonNullTail(aStartPriorityLevel));
}
Message *mTails[Message::kNumPriorities]; // Tail pointers associated with different priority levels.
};
/**
* This class represents a message pool
*
*/
class MessagePool : public InstanceLocator, private NonCopyable
{
friend class Message;
friend class MessageQueue;
friend class PriorityQueue;
public:
/**
* This constructor initializes the object.
*
*/
explicit MessagePool(Instance &aInstance);
/**
* This method allocates a new message with specified settings.
*
* @param[in] aType The message type.
* @param[in] aReserveHeader The number of header bytes to reserve.
* @param[in] aSettings The message settings.
*
* @returns A pointer to the message or `nullptr` if no message buffers are available.
*
*/
Message *Allocate(Message::Type aType,
uint16_t aReserveHeader = 0,
const Message::Settings &aSettings = Message::Settings::GetDefault());
/**
* This method is used to free a message and return all message buffers to the buffer pool.
*
* @param[in] aMessage The message to free.
*
*/
void Free(Message *aMessage);
/**
* This method returns the number of free buffers.
*
* @returns The number of free buffers.
*
*/
uint16_t GetFreeBufferCount(void) const;
/**
* This method returns the total number of buffers.
*
* @returns The total number of buffers.
*
*/
uint16_t GetTotalBufferCount(void) const;
private:
Buffer *NewBuffer(Message::Priority aPriority);
void FreeBuffers(Buffer *aBuffer);
Error ReclaimBuffers(Message::Priority aPriority);
#if !OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT && !OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
uint16_t mNumFreeBuffers;
Pool<Buffer, kNumBuffers> mBufferPool;
#endif
};
inline Instance &Message::GetInstance(void) const
{
return GetMessagePool()->GetInstance();
}
/**
* @}
*
*/
DefineCoreType(otMessageBuffer, Buffer);
DefineCoreType(otMessageSettings, Message::Settings);
DefineCoreType(otMessage, Message);
DefineCoreType(otMessageQueue, MessageQueue);
} // namespace ot
#endif // MESSAGE_HPP_