_ak_stream_mgr_module_8h

Wwise SDK 2022.1.18

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 released in source code form as part of the SDK installer package.
  
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 /// \file 
 /// Audiokinetic's implementation-specific definitions and factory of 
 /// overridable Stream Manager module.
 /// Contains the default Stream Manager's implementation-specific interfaces that altogether constitute
 /// the Low-Level I/O submodule. This submodule needs to be implemented by the game. All I/O requests 
 /// generated by the Stream Manager end up to one of the I/O hooks defined herein.
 /// Read \ref streamingmanager_lowlevel to learn more about the Low-Level I/O.
  
 #ifndef _AK_STREAM_MGR_MODULE_H_
 #define _AK_STREAM_MGR_MODULE_H_
  
 #include <AK/SoundEngine/Common/IAkStreamMgr.h>
 #include <AK/Tools/Common/AkPlatformFuncs.h>
  
 class CAkFilePackage;
  
 /// \name Audiokinetic Stream Manager's implementation-specific definitions.
 //@{
 /// Stream Manager initialization settings.
 /// \sa 
 /// - AK::IAkStreamMgr
 /// - AK::StreamMgr::Create()
 /// - \ref streamingmanager_settings
  
 struct AkStreamMgrSettings
 {
 };
  
 /// High-level IO devices initialization settings.
 /// \sa 
 /// - AK::IAkStreamMgr
 /// - AK::StreamMgr::CreateDevice()
 /// - \ref streamingmanager_settings
 struct AkDeviceSettings
 {
     void *              pIOMemory;                  ///< Pointer for I/O memory allocated by user.
                                                     ///< Pass NULL if you want memory to be allocated via AK::MemoryMgr::Malign().
                                                     ///< If specified, uIOMemorySize, uIOMemoryAlignment and ePoolAttributes are ignored.
     AkUInt32            uIOMemorySize;              ///< Size of memory for I/O (for automatic streams). It is passed directly to AK::MemoryMgr::Malign(), after having been rounded down to a multiple of uGranularity.
     AkUInt32            uIOMemoryAlignment;         ///< I/O memory alignment. It is passed directly to AK::MemoryMgr::Malign().
     AkUInt32            ePoolAttributes;            ///< Attributes for I/O memory. Here, specify the allocation type (AkMemType_Device, and so on). It is passed directly to AK::MemoryMgr::Malign().
     AkUInt32            uGranularity;               ///< I/O requests granularity (typical bytes/request).
     AkUInt32            uSchedulerTypeFlags;        ///< Scheduler type flags.
     AkThreadProperties  threadProperties;           ///< Scheduler thread properties.
     AkReal32            fTargetAutoStmBufferLength; ///< Targetted automatic stream buffer length (ms). When a stream reaches that buffering, it stops being scheduled for I/O except if the scheduler is idle.
     AkUInt32            uMaxConcurrentIO;           ///< Maximum number of transfers that can be sent simultaneously to the Low-Level I/O.
     bool                bUseStreamCache;            ///< If true, the device attempts to reuse I/O buffers that have already been streamed from disk. This is particularly useful when streaming small looping sounds. However, there is a small increase in CPU usage when allocating memory, and a slightly larger memory footprint in the StreamManager pool.                                                    
     AkUInt32            uMaxCachePinnedBytes;       ///< Maximum number of bytes that can be "pinned" using AK::SoundEngine::PinEventInStreamCache() or AK::IAkStreamMgr::PinFileInCache()
 };
  
 /// \name Scheduler type flags.
  
 /// Requests to Low-Level IO are synchronous. The streaming device expects a blocking I/O hook at creation time (IAkIOHookBlocking interface, see CreateDevice()). 
 /// Functions of this interface should return only when the transfer is complete.
 #define AK_SCHEDULER_BLOCKING          (0x01)
 /// Requests to Low-Level IO are asynchronous, but posted one after the other, starting with streams that need data the most. 
 /// The streaming device expects a deferred I/O hook at creation time (IAkIOHookDeferredBatch interface, see CreateDevice()). 
 /// Up to AkDeviceSettings::uMaxConcurrentIO requests can be sent to the Low-Level I/O at the same time.
 #define AK_SCHEDULER_DEFERRED_LINED_UP (0x02)
  
 /// File descriptor. File identification for the low-level I/O.
 /// \sa
 /// - AK::StreamMgr::IAkLowLevelIOHook
 struct AkFileDesc
 {
     AkInt64             iFileSize;          ///< File size in bytes
     AkUInt64            uSector;            ///< Start sector (the sector size is specified by the low-level I/O)
                                             ///< \sa
                                             ///< - AK::StreamMgr::IAkFileLocationResolver::Open()
                                             ///< - AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize()
     AkUInt32            uCustomParamSize;   ///< Size of the custom parameter
     void *              pCustomParam;       ///< Custom parameter
     AkFileHandle        hFile;              ///< File handle/identifier
     AkDeviceID          deviceID;           ///< Device ID, obtained from CreateDevice() \sa AK::IAkStreamMgr::CreateDevice()
     CAkFilePackage*     pPackage;           ///< If this file is in a File Package, this will be the 
 };
  
 /// Structure for synchronous transfers handshaking with the Low-Level I/O. Used with blocking I/O hooks.
 /// \sa AK::StreamMgr::IAkIOHookBlocking
 struct AkIOTransferInfo
 {
     AkUInt64        uFilePosition;      ///< File offset where transfer should begin.
     AkUInt32        uBufferSize;        ///< Size of the buffer in which the I/O hook can write to.
     AkUInt32        uRequestedSize;     ///< Exact number of requested bytes for this transfer. Always equal to or smaller than uBufferSize.
 };
  
 struct AkAsyncIOTransferInfo;
  
 /// Callback function prototype definition used for asynchronous I/O transfers between the Stream Manager
 /// and the Low-Level IO. Used with deferred I/O hooks.
 /// Notes:
 /// - If you pass in_eResult of AK_Fail, all streams awaiting for this transfer are marked as invalid and will stop. An "IO error" notification is posted to the capture log.
 /// - If the transfer was cancelled by the Stream Manager while it was in the Low-Level IO, you must return AK_Success, whether
 /// you performed the operation or not. The Stream Manager knows that it was cancelled, so it will not try to use it after you call it back.
 /// \sa 
 /// - AkAsyncIOTransferInfo
 /// - AK::StreamMgr::IAkIOHookDeferredBatch
 AK_CALLBACK( void, AkIOCallback )( 
     AkAsyncIOTransferInfo * in_pTransferInfo,   ///< Pointer to the AkAsyncIOTransferInfo structure that was passed to corresponding Read() or Write() call.
     AKRESULT        in_eResult                  ///< Result of transfer: AK_Success or AK_Fail (streams waiting for this transfer become invalid).
     );
  
 /// Callback function prototype definition used for asynchronous I/O transfers between the Stream Manager
 /// and the Low-Level IO. Used with batch deferred I/O hooks.
 /// Notes:
 /// - in_peResult and in_ppTransferInfo must both contain in_uNumTransfers number of elements
 /// - For each in_peResult with a value of AK_Fail, all streams awaiting for the corresponding transfer are marked as invalid and will stop. An "IO error" notification is posted to the capture log.
 /// - If a given transfer was cancelled by the Stream Manager while it was in the Low-Level IO, you must return AK_Success for that result, whether
 /// you performed the operation or not. The Stream Manager knows that it was cancelled, so it will not try to use it after you call it back.
 /// - Note that one call to BatchRead, BatchWrite or BatchCancel does not have to result in one execution of the callback. The only requirement is that
 /// each element of in_ppTransferInfo passed in only has the IOCallback fired on it one time.
 /// \sa 
 /// - AkAsyncIOTransferInfo
 /// - AK::StreamMgr::IAkIOHookDeferredBatch
 AK_CALLBACK(void, AkBatchIOCallback)(
     AkUInt32                in_uNumTransfers,   ///< Number of transfers to process
     AkAsyncIOTransferInfo** in_ppTransferInfo,  ///< List of pointers to AkAsyncIOTransferInfo structures that were previously passed in to BatchRead() or BatchWrite()
     AKRESULT*               in_peResult         ///< Array of results of each transfer: AK_Success or AK_Fail (streams waiting for this transfer become invalid).
     );
  
 /// Structure for asynchronous transfers handshaking with the Low-Level I/O. Extends AkIOTransferInfo.
 /// \sa 
 /// - AK::StreamMgr::IAkIOHookDeferredBatch
 /// - AkIOTransferInfo
 /// - AkAIOCallback
 struct AkAsyncIOTransferInfo : public AkIOTransferInfo
 {
     void *          pBuffer;            ///< Buffer for data transfer.
     AkIOCallback    pCallback;          ///< Callback function used to notify the high-level device when the transfer is complete.
     void *          pCookie;            ///< Reserved. The I/O device uses this cookie to retrieve the owner of the transfer.
     void *          pUserData;          ///< Custom user data.
 };
  
 /// Low-Level I/O requests heuristics.
 /// Used for asynchronous read requests. 
 /// \sa 
 /// - AK::StreamMgr::IAkIOHookBlocking::Read()
 /// - AK::StreamMgr::IAkIOHookBlocking::Write()
 /// - AK::StreamMgr::IAkIOHookDeferredBatch::Read()
 /// - AK::StreamMgr::IAkIOHookDeferredBatch::Write()
 struct AkIoHeuristics
 {
     AkReal32        fDeadline;          ///< Operation deadline (ms). 
     AkPriority      priority;           ///< Operation priority (at the time it was scheduled and sent to the Low-Level I/O). Range is [AK_MIN_PRIORITY,AK_MAX_PRIORITY], inclusively.
 };
  
  
  
 //@}
  
 namespace AK
 {
     /// Audiokinetic Stream Manager's implementation-specific interfaces of the Low-Level IO submodule.
     namespace StreamMgr
     {
         /// Base interface for Low-Level I/O hooks. Defines common methods across both types of hooks.
         class IAkLowLevelIOHook
         {
         protected:
             /// Virtual destructor on interface to avoid warnings.
             virtual ~IAkLowLevelIOHook(){}
  
         public:
             /// Cleans up a file.
             /// \return AK_Success if the file was properly cleaned-up.
             virtual AKRESULT Close(
                 AkFileDesc &            in_fileDesc         ///< File descriptor.
                 ) = 0;
  
             /// Returns the block size for the file or its storage device. 
             /// The block size is a constraint for clients
             /// of the Stream Manager: All reads, writes and position changes need to be a multiple of
             /// that size.
             /// \return 
             /// The block size for a specific file or storage device.
             /// \remarks 
             /// - Some files might be opened with flags that require I/O transfers to be a multiple 
             /// of this size. The stream manager will query this function to resolve calls 
             /// to IAk(Auto)Stream::GetBlockSize( ).
             /// - Also, AkFileDesc::uSector specifies a number of sectors in multiples of this value.
             /// - Files/IO devices that do not require byte alignment should return 1.
             /// - Whether file opening was deferred or not, GetBlockSize() is always called right 
             /// after the first call to Open(), in the client's thread, and is never called again.
             /// \warning 
             /// Returning 0 is not allowed and will likely make the Stream Manager crash.
             /// \sa 
             /// - AK::StreamMgr::IAkFileLocationResolver::Open()
             /// - AK::StreamMgr::IAkIOHookBlocking::Read()
             /// - AK::StreamMgr::IAkIOHookBlocking::Write()
             /// - AK::StreamMgr::IAkIOHookDeferredBatch::Read()
             /// - AK::StreamMgr::IAkIOHookDeferredBatch::Write()
             virtual AkUInt32 GetBlockSize(
                 AkFileDesc &            in_fileDesc         ///< File descriptor.
                 ) = 0;
  
             /// Returns a description for the streaming device above this low-level hook.
             /// \remarks For profiling purposes only. The Release configuration of the 
             /// Stream Manager never calls it.
             virtual void GetDeviceDesc(
                 AkDeviceDesc &          out_deviceDesc      ///< Device description.
                 ) = 0;
  
             /// Returns custom profiling data for the streaming device above this low-level hook.
             /// As opposed to GetDeviceDesc(), this is called at every monitoring frame.
             /// You may implement this function in order to display any value you find useful 
             /// in the "Streaming Devices" tab of the Wwise profiler ("Custom Param" column).
             /// \remarks For profiling purposes only. The Release configuration of the 
             /// Stream Manager never calls it.
             /// \return A 32-bit unsigned value to display in the Wwise profiler.
             virtual AkUInt32 GetDeviceData() = 0;
         };
  
         /// Interface for blocking low-level I/O transfers. Used by streaming devices created with the
         /// AK_SCHEDULER_BLOCKING flag.
         /// This is the simplest I/O hook. Calls to Read()/Write() must block until they are completed.
         /// The streaming device's I/O thread sends one transfer at a time.
         class IAkIOHookBlocking : public IAkLowLevelIOHook
         {
         protected:
             /// Virtual destructor on interface to avoid warnings.
             virtual ~IAkIOHookBlocking(){}
  
         public:
  
             /// Reads data from a file (synchronous). 
             /// Read data from the file described by in_fileDesc, in address out_pBuffer and with size and position 
             /// passed within io_transferInfo. When transfer is complete, return with the proper return code.
             /// \remarks 
             /// File position passed in io_transferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "in_fileDesc.uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             /// \return 
             ///     - AK_Success:   transfer was successful and out_pBuffer is filled with data.
             ///     - AK_Fail:      an error occured.
             virtual AKRESULT Read(
                 AkFileDesc &            in_fileDesc,        ///< File descriptor.
                 const AkIoHeuristics &  in_heuristics,      ///< Heuristics for this data transfer.
                 void *                  out_pBuffer,        ///< Buffer to be filled with data.
                 AkIOTransferInfo &      in_transferInfo     ///< Synchronous data transfer info. 
                 ) = 0;
  
             /// Writes data to a file (synchronous). 
             /// Write data to the file described by in_fileDesc, from address in_pData and with size and position 
             /// passed within io_transferInfo. When transfer is complete, return with the proper return code.
             /// \remarks File position passed in io_transferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "in_fileDesc.uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             /// \return 
             ///     - AK_Success:   transfer was successful.
             ///     - AK_Fail:      an error occured.
             virtual AKRESULT Write(
                 AkFileDesc &            in_fileDesc,        ///< File descriptor.
                 const AkIoHeuristics &  in_heuristics,      ///< Heuristics for this data transfer.
                 void *                  in_pData,           ///< Data to be written.
                 AkIOTransferInfo &      io_transferInfo     ///< Synchronous data transfer info. 
                 ) = 0;
         };
  
         /// Interface for batched deferred low-level I/O transfers. Used by streaming devices created
         /// with the AK_SCHEDULER_DEFERRED_LINED_UP flag.
         /// This I/O transfer handshaking method is preferred when you want to hook I/O to your own
         /// I/O streaming technology, and you want to submit multiple I/O requests in one call, so as
         /// to allow for better opportunities for CPU and I/O performance.
         /// You may queue them into your own system, and even use the heuristics passed down to this
         /// level for your convenience. Note that the requests are always sent in the order that the
         /// Stream Manager considers to be the most appropriate. You may receive less than
         /// AkDeviceSettings::uMaxConcurrentIO at any given time. The number of concurrent transfers
         /// depends on the number of streams running in the high-level streaming device, and on its
         /// target buffering length and granularity. Your advantage at this level is to be aware of
         /// file placement, so you may try to re-order requests in order to minimize seeking on disk. 
         /// Calls to BatchRead()/BatchWrite() should return as soon as possible. You need to call 
         /// AkAsyncIOTransferInfo::pCallback for an individual item, or AkBatchIOCallback for a collection
         /// of items as soon as a transfer is completed.
         /// Cancel() is provided in order to inform you that the streaming device will flush this transfer
         /// upon completion. You may implement it or not. In all cases, you must call the callback.
         class IAkIOHookDeferredBatch : public IAkLowLevelIOHook
         {
         protected:
             /// Virtual destructor on interface to avoid warnings.
             virtual ~IAkIOHookDeferredBatch() {}
  
         public:
             struct BatchIoTransferItem
             {
                 AkFileDesc* pFileDesc;
                 AkIoHeuristics ioHeuristics;
                 AkAsyncIOTransferInfo* pTransferInfo;
             };
  
             /// Reads multiple data from multiple files (asynchronous).
             /// \remarks 
             /// - Queue up multiple read requests at once, using the provided array of in_pTransferItems. There will
             /// be in_uNumTransfers number of items in the array.
             /// - io_pDispatchResults will contain an in_uNumTransfers number of items in the array. Each item in
             /// io_pDispatchResults should be set to AK_Success if the corresponding Read was successfully dispatched,
             /// and set to AK_Failure otherwise. As well, the return value should be a cumulative result of the
             /// dispatches, where AK_Success indicates all requests were dispatched successfully, and
             /// io_pDispatchResults will not be investigated, whereas AK_Fail indicates at least one failure.
             /// - When a given Read, or some set of reads has completed - whether it was successful, cancelled,
             /// or failed - call in_pBatchIoCallback for the corresponding transfer. Pass in the list of
             /// AkAsyncIOTransferInfo objects to receive the callback, as well as a list of results for each transfer,
             /// e.g. AK_Success or some other AKRESULT. Do not call in_pBatchIoCallback for transfers that were not
             /// dispatched (as indicated by the corresponding value in io_pDispatchResults).
             /// - The pointer to each BatchIoTransferItem::pTransferInfo will be valid until the high-level
             /// device is notified through the callback. The array of in_pTransferItems will not be valid, though.
             /// - File position passed in each BatchIoTransferItem::pTransferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "pFileDesc->uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             ///
             /// \return 
             ///     - AK_Success:    All I/O requests were successfully dispatched.
             ///                      in_pBatchIoCallback must be called for each read that completes.
             ///     - AK_Fail:       At least one failure occurred when dispatching reads.
             ///                      The values of io_pDispatchResults should indicate which operation failed to be dispatched.
             virtual AKRESULT BatchRead(
                 AkUInt32                        in_uNumTransfers,       ///< Number of transfers to process
                 BatchIoTransferItem*            in_pTransferItems,      ///< List of transfer items to process
                 AkBatchIOCallback               in_pBatchIoCallback,    ///< Callback to execute to handle completion of multiple items simultaneously
                 AKRESULT*                       io_pDispatchResults     ///< Output result codes to indicate if a transfer was successfully dispatched
             ) = 0;
  
             /// Write multiple data to multiple files (asynchronous).
             /// \remarks 
             /// - Queue up multiple write requests at once, using the provided array of in_pTransferItems. There will
             /// be in_uNumTransfers number of items in the array.
             /// - io_pDispatchResults will contain an in_uNumTransfers number of items in the array. Each item in
             /// io_pDispatchResults should be set to AK_Success if the corresponding write was successfully dispatched,
             /// and set to AK_Failure otherwise. As well, the return value should be a cumulative result of the
             /// dispatches, where AK_Success indicates all requests were dispatched successfully, and
             /// io_pDispatchResults will not be investigated, whereas AK_Fail indicates at least one failure.
             /// - When a given write, or some set of writes has completed - whether it was successful, cancelled,
             /// or failed - call in_pBatchIoCallback for the corresponding transfer. Pass in the list of
             /// AkAsyncIOTransferInfo objects to receive the callback, as well as a list of results for each transfer,
             /// e.g. AK_Success or some other AKRESULT. Do not call in_pBatchIoCallback for transfers that were not
             /// dispatched (as indicated by the corresponding value in io_pDispatchResults).
             /// - The pointer to each BatchIoTransferItem::pTransferInfo will be valid until the high-level
             /// device is notified through the callback. The array of in_pTransferItems will not be valid, though.
             /// - File position passed in each BatchIoTransferItem::pTransferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "pFileDesc->uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             ///
             /// \return 
             ///     - AK_Success:    All I/O requests were successfully dispatched.
             ///                      in_pBatchIoCallback must be called for each write that completes.
             ///     - AK_Fail:       At least one failure occurred when dispatching writes.
             ///                      The values of io_pDispatchResults should indicate which operation failed to be dispatched.
             virtual AKRESULT BatchWrite(
                 AkUInt32                        in_uNumTransfers,       ///< Number of transfers to process
                 BatchIoTransferItem*            in_pTransferItems,      ///< List of transfer items to process
                 AkBatchIOCallback               in_pBatchIoCallback,    ///< Callback to execute to handle completion of multiple items simultaneously
                 AKRESULT*                       io_pDispatchResults     ///< Output result codes to indicate if a transfer was successfully dispatched
             ) = 0;
  
             /// Notifies that a transfer request is cancelled. It will be flushed by the streaming device when completed.
             /// Cancellation is normal and happens regularly; for example, whenever a sound stops before the end
             /// or stops looping. It happens even more frequently when buffering (AkDeviceSettings::fTargetAutoStmBufferLength 
             /// and AkDeviceSettings::uGranularity) is large and when you low-level IO hook accepts many concurrent requests
             /// at the same time.
             /// \remarks
             /// - Cancel() simply informs the Low-Level I/O that a specific transfer will be flushed upon reception. 
             /// The Low-Level I/O may use this information to stop this transfer right away, or not (it is internally tagged
             /// by the high-level device as cancelled). Nevertheless, the callback function MUST be called for cancelled 
             /// transfers to be resolved.
             /// - When calling the callback function of a cancelled transfer, pass it *AK_Success*. Passing AK_Fail 
             /// to AkAsyncIOTransfer::pCallback has the effect of killing the stream once and for all. This is not
             /// what you want.
             /// - If io_bCancelAllTransfersForThisFile is set, you may cancel all transfers for this file at once.
             /// Leave io_bCancelAllTransfersForThisFile to true if you don't want to be called again. For example, if
             /// you don't do anything special in Cancel(), leave it to true. This will reduce the amount of useless calls.
             /// If you set it to false, Cancel() will be called again for each remaining pending transfer that need to be cancelled. 
             /// - If io_bCancelAllTransfersForThisFile is not set, Cancel() is only called for a subset of pending 
             /// transfers for this file. You must not set it to true, as Cancel() needs to be called explicitly for each transfer that should be cancelled.
             /// \warning
             /// - The calling thread holds the stream's lock. You may call the callback function directly from here
             /// (if you can guarantee that the I/O buffer will not be accessed in the meantime), but you must not wait here 
             /// for another thread to call the callback function.
             /// - Likewise, if you resolve transfers with your own thread and use a lock to protect your transfers queue, 
             /// be careful not to run into a deadlock. Cancel() can be executed by any thread. Thus, if you need to lock your queue 
             /// in Cancel(), you must never hold this lock when calling back transfers, either from within Cancel() or from your 
             /// worker thread's routine. Lock your list, dequeue the transfer if you can, unlock, and call pCallback if and only if 
             /// the transfer was found and dequeued. On the other hand, if you choose not to do anything in Cancel(), the lock only protects 
             /// your list between Read()/Write() and your worker thread's routine, and since the device I/O thread does not hold the 
             /// stream's lock while calling Read()/Write(), your worker thread may therefore hold it while calling back transfers.
             /// - A race condition exists when cancelling all transfers (io_bCancelAllTransfersForThisFile is true) directly from within this hook. 
             /// If you handle the io_bCancelAllTransfersForThisFile == true case, you need to defer calling the completion callback to later 
             /// (from your usual I/O completion thread, for example). This will be fixed in a future version of Wwise.
             virtual void BatchCancel(
                 AkUInt32                        in_uNumTransfers,                       ///< Number of transfers to process
                 BatchIoTransferItem*            in_pTransferItems,                      ///< List of transfer items to process
                 bool**                          io_ppbCancelAllTransfersForThisFile     ///< Flag for each transfer indicating whether all transfers should be cancelled for this file (see notes in function description).
             ) = 0;
         };
  
  
         /// Interface for deferred low-level I/O transfers. Used by streaming devices created with the
         /// AK_SCHEDULER_DEFERRED_LINED_UP flag.
         /// This is an "adapter" interface to forward calls to IAkIOHookDeferredBatch, to maintain
         /// compatibility with existing implementations, as well as provide a simpler interface for new
         /// implementations.
         /// This I/O transfer handshaking method is preferred when you want to hook I/O to your own
         /// I/O streaming technology. You will receive up to AkDeviceSettings::uMaxConcurrentIO requests
         /// at the same time. You may queue them into your own system, and even use the heuristics passed
         /// down to this level for your convenience. 
         /// Note that the requests are always sent in the order that the Stream Manager considers to be
         /// the most appropriate. You may receive less than AkDeviceSettings::uMaxConcurrentIO at any
         /// given time. The number of concurrent transfers depends on the number of streams running in 
         /// the high-level streaming device, and on its target buffering length and granularity.
         /// Your advantage at this level is to be aware of file placement, so you may try to re-order 
         /// requests in order to minimize seeking on disk. 
         /// Calls to Read()/Write() should return as soon as possible. You need to call 
         /// AkAsyncIOTransferInfo::pCallback as soon as a transfer is completed.
         /// Cancel() is provided in order to inform you that the streaming device will flush this transfer
         /// upon completion. You may implement it or not. In all cases, you must call the callback.
         class IAkIOHookDeferred : public IAkIOHookDeferredBatch
         {
         protected:
             /// Virtual destructor on interface to avoid warnings.
             virtual ~IAkIOHookDeferred(){}
  
         public:
             /// Reads data from a file (asynchronous).
             /// \remarks 
             /// - Queue up your read request with address, size and file position specified in io_transferInfo.
             /// - When transfer is complete (whether it was successful, cancelled or failed), call 
             /// AkAsyncIOTransferInfo::pCallback. However, if you return AK_Fail() from Read(), do not call
             /// AkAsyncIOTransferInfo::pCallback.
             /// - AkAsyncIOTransferInfo::pCookie must be passed to the callback function as-is. It must not
             /// be changed by the Low-Level I/O.
             /// - The reference to io_transferInfo will be valid until the high-level device is notified 
             /// through the callback.
             /// - File position passed in io_transferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "in_fileDesc.uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             /// \return 
             ///     - AK_Success:   An I/O request was successfully dispatched and is pending: 
             ///                     AkAsyncIOTransferInfo::pCallback must be called when it completes.
             ///     - AK_Fail:      An error occurred, no I/O request was dispatched
             virtual AKRESULT Read(
                 AkFileDesc &            in_fileDesc,        ///< File descriptor.
                 const AkIoHeuristics &  in_heuristics,      ///< Heuristics for this data transfer.
                 AkAsyncIOTransferInfo & io_transferInfo     ///< Asynchronous data transfer info.
                 ) = 0;
  
             /// Writes data to a file (asynchronous).
             /// \remarks 
             /// - Queue up your write request with address, size and file position specified in io_transferInfo.
             /// - When transfer is complete (whether it was successful, cancelled or failed), call 
             /// AkAsyncIOTransferInfo::pCallback. However, if you return AK_Fail() from Write(), do not call
             /// AkAsyncIOTransferInfo::pCallback.
             /// - AkAsyncIOTransferInfo::pCookie must be passed to the callback function as-is. It must not
             /// be changed by the Low-Level I/O.
             /// - The reference to io_transferInfo will be valid until the high-level device is notified 
             /// through the callback.
             /// - File position passed in io_transferInfo takes the offset of this file relative 
             /// to AkFileDesc::hFile (described with AkFileDesc::uSector). It is computed by the high-level 
             /// device as "in_fileDesc.uSector * Block_Size + Stream_Position", where Block_Size is obtained 
             /// via AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize(). 
             /// \return 
             ///     - AK_Success:    An I/O request was successfully processed and is pending: 
             ///                         AkAsyncIOTransferInfo::pCallback must be called when it completes.
             ///     - AK_Fail:        an error occured.
             virtual AKRESULT Write(
                 AkFileDesc &            in_fileDesc,        ///< File descriptor.
                 const AkIoHeuristics &  in_heuristics,      ///< Heuristics for this data transfer.
                 AkAsyncIOTransferInfo & io_transferInfo     ///< Platform-specific asynchronous IO operation info.
                 ) = 0;
  
             /// Notifies that a transfer request is cancelled. It will be flushed by the streaming device when completed.
             /// Cancellation is normal and happens regularly; for example, whenever a sound stops before the end
             /// or stops looping. It happens even more frequently when buffering (AkDeviceSettings::fTargetAutoStmBufferLength 
             /// and AkDeviceSettings::uGranularity) is large and when you low-level IO hook accepts many concurrent requests
             /// at the same time.
             /// \remarks
             /// - Cancel() simply informs the Low-Level I/O that a specific transfer will be flushed upon reception. 
             /// The Low-Level I/O may use this information to stop this transfer right away, or not (it is internally tagged
             /// by the high-level device as cancelled). Nevertheless, the callback function MUST be called for cancelled 
             /// transfers to be resolved.
             /// - When calling the callback function of a cancelled transfer, pass it *AK_Success*. Passing AK_Fail 
             /// to AkAsyncIOTransfer::pCallback has the effect of killing the stream once and for all. This is not
             /// what you want.
             /// - If io_bCancelAllTransfersForThisFile is set, you may cancel all transfers for this file at once.
             /// Leave io_bCancelAllTransfersForThisFile to true if you don't want to be called again. For example, if
             /// you don't do anything special in Cancel(), leave it to true. This will reduce the amount of useless calls.
             /// If you set it to false, Cancel() will be called again for each remaining pending transfer that need to be cancelled. 
             /// - If io_bCancelAllTransfersForThisFile is not set, Cancel() is only called for a subset of pending 
             /// transfers for this file. You must not set it to true, as Cancel() needs to be called explicitly for each transfer that should be cancelled.
             /// \warning
             /// - The calling thread holds the stream's lock. You may call the callback function directly from here
             /// (if you can guarantee that the I/O buffer will not be accessed in the meantime), but you must not wait here 
             /// for another thread to call the callback function.
             /// - Likewise, if you resolve transfers with your own thread and use a lock to protect your transfers queue, 
             /// be careful not to run into a deadlock. Cancel() can be executed by any thread. Thus, if you need to lock your queue 
             /// in Cancel(), you must never hold this lock when calling back transfers, either from within Cancel() or from your 
             /// worker thread's routine. Lock your list, dequeue the transfer if you can, unlock, and call pCallback if and only if 
             /// the transfer was found and dequeued. On the other hand, if you choose not to do anything in Cancel(), the lock only protects 
             /// your list between Read()/Write() and your worker thread's routine, and since the device I/O thread does not hold the 
             /// stream's lock while calling Read()/Write(), your worker thread may therefore hold it while calling back transfers.
             /// - A race condition exists when cancelling all transfers (io_bCancelAllTransfersForThisFile is true) directly from within this hook. 
             /// If you handle the io_bCancelAllTransfersForThisFile == true case, you need to defer calling the completion callback to later 
             /// (from your usual I/O completion thread, for example). This will be fixed in a future version of Wwise.
             virtual void Cancel(
                 AkFileDesc &        in_fileDesc,            ///< File descriptor.
                 AkAsyncIOTransferInfo & io_transferInfo,    ///< Transfer info to cancel.
                 bool & io_bCancelAllTransfersForThisFile    ///< Flag indicating whether all transfers should be cancelled for this file (see notes in function description).
                 ) = 0;
  
             /// The following functions each provide "stub" implementations of IAkHookDeferredIOBatch operations, so as to forward calls to 
             /// the existing single-transfer variants. The soundengine never calls IAkHookDeferred::Read et al, internally, and only
             /// ever calls IAkIOHookDeferredBatch::BatchRead et al. 
             virtual AKRESULT BatchRead(
                 AkUInt32                in_uNumTransfers,       ///< Number of transfers to process
                 BatchIoTransferItem*    in_pTransferItems,      ///< List of transfer items to process
                 AkBatchIOCallback       /*in_pBatchIoCallback*/,///< Callback to execute to handle completion of multiple items simultaneously
                 AKRESULT*               io_pDispatchResults     ///< Output result codes to indicate if a transfer was successfully dispatched
             )
             {
                 AKRESULT cumulativeResult = AK_Success;
                 for (AkUInt32 i = 0; i < in_uNumTransfers; ++i)
                 {
                     BatchIoTransferItem ioTransferItem = in_pTransferItems[i];
                     AKRESULT result = Read(*(ioTransferItem.pFileDesc), ioTransferItem.ioHeuristics, *(ioTransferItem.pTransferInfo));
                     io_pDispatchResults[i] = result;
                     cumulativeResult = result == AK_Success ? cumulativeResult : AK_Fail;
                 }
                 return cumulativeResult;
             }
  
             virtual AKRESULT BatchWrite(
                 AkUInt32                in_uNumTransfers,       ///< Number of transfers to process
                 BatchIoTransferItem*    in_pTransferItems,      ///< List of transfer items to process
                 AkBatchIOCallback       /*in_pBatchIoCallback*/,///< Callback to execute to handle completion of multiple items simultaneously
                 AKRESULT*               io_pDispatchResults     ///< Output result codes to indicate if a transfer was successfully dispatched
             )
             {
                 AKRESULT cumulativeResult = AK_Success;
                 for (AkUInt32 i = 0; i < in_uNumTransfers; ++i)
                 {
                     BatchIoTransferItem ioTransferItem = in_pTransferItems[i];
                     AKRESULT result = Write(*(ioTransferItem.pFileDesc), ioTransferItem.ioHeuristics, *(ioTransferItem.pTransferInfo));
                     io_pDispatchResults[i] = result;
                     cumulativeResult = result == AK_Success ? cumulativeResult : AK_Fail;
                 }
                 return cumulativeResult;
             }
             virtual void BatchCancel(
                 AkUInt32                in_uNumTransfers,       ///< Number of transfers to process
                 BatchIoTransferItem*    in_pTransferItems,      ///< List of transfer items to process
                 bool** io_ppbCancelAllTransfersForThisFile      ///< Flag for each transfer indicating whether all transfers should be cancelled for this file (see notes in function description).
             )
             {
                 for (AkUInt32 i = 0; i < in_uNumTransfers; ++i)
                 {
                     BatchIoTransferItem ioTransferItem = in_pTransferItems[i];
                     Cancel(*(ioTransferItem.pFileDesc), *(ioTransferItem.pTransferInfo), *(io_ppbCancelAllTransfersForThisFile[i]));
                 }
             }
  
         };
  
         /// File location resolver interface. There is one and only one File Location Resolver that is
         /// registered to the Stream Manager (using AK::StreamMgr::SetFileLocationResolver()). Its purpose
         /// is to map a file name or ID to 
         /// 1) a streaming device / I/O hook;
         /// 2) a valid file descriptor (AkFileDesc) usable by the I/O hook.
         /// When your Low-Level I/O submodule uses a single device, you should create a standalone I/O
         /// hook which implements one of the I/O hooks defined above (blocking or deferred), as well 
         /// as the File Location Resolver. You then register this object to the Stream Manager as the 
         /// File Location Resolver.
         /// If you wish to create multiple devices, then you should have a separate object that implements
         /// AK::StreamMgr::IAkFileLocationResolver and registers to the Stream Manager as such. This object
         /// will be used to dispatch the file open request to the appropriate device. The strategy you will 
         /// use to select the correct device is up to you to implement. You may also implement a set of
         /// hooks that delegate opening to the next device when they can't find the file requested 
         /// (like a chain of responsiblity pattern), although this will likely be less efficient.
         class IAkFileLocationResolver
         {
         protected:
             /// Virtual destructor on interface to avoid warnings.
             virtual ~IAkFileLocationResolver(){}
  
         public:
  
             /// Returns a file descriptor for a given file name (string).
             /// Performs the operations needed to make the file descriptor usable by
             /// the other methods of the interface (for e.g. ask the OS for a valid file handle).
             /// \return 
             ///     - AK_Success:       A valid file descriptor is returned
             ///     - AK_FileNotFound:  File was not found.
             ///     - AK_Fail:          File could not be open for any other reason.
             /// \return 
             ///     - A file descriptor, that contains 
             ///         - an unique identifier to be used with functions of the low-level IO 
             ///           interface.
             ///         - the total stream size in bytes.
             ///         - the offset from the beginning of the file (in blocks).
             ///         - a device ID, that was obtained through AK::StreamMgr::CreateDevice().
             ///     - The updated io_bSyncOpen flag depending on the File Resolver's deferred opening policy.
             /// \remarks
             ///     - The file descriptor is unique for each stream, and its address remains the same 
             ///     throughout its lifetime. In other words, the value of &in_fileDesc inside Read() or
             ///     Close() is the same as &out_fileDesc in Open().
             ///     - Open() is always called first in the client thread.
             ///     - If io_bSyncOpen is true, file opening must be executed now. If it is false,
             ///     the File Location Resolver may choose whether it wants open it now, or later
             ///     from the streaming device's thread. If it wishes to open it now, then it must
             ///     set io_bSyncOpen to true. Otherwise, it needs to do the following: leave 
             ///     io_bSyncOpen to false, clear out_fileDesc::iFileSize and out_fileDesc::uSector, 
             ///     and set out_fileDesc::deviceID to the streaming device's ID that will handle 
             ///     this file. By returning io_bSyncOpen as false, the Stream Manager will interpret
             ///     this as a request for deferred file opening, and this function will called again
             ///     from the streaming device's thread (this time, with this io_bSyncOpen set to true).
             ///     - All members of out_fileDesc will be cleared upon first call to Open().
             /// \warning
             ///     - It is illegal to return io_bSyncOpen as false if Open() was called with io_bSyncOpen
             ///     set to true.
             ///     - Deferred file opening requires allocations in the Stream Manager's small object pool.
             ///     The File Location Resolver should always choose to open files synchronously if it is 
             ///     fast to do so.
             ///     - Whether opening is deferred or not, GetBlockSize() is always called right after the
             ///     first call to Open(), in the client's thread, and is never called again.
             /// \sa 
             /// - GetBlockSize()
             /// - \ref streamingmanager_lowlevel_location
             virtual AKRESULT Open( 
                 const AkOSChar*         in_pszFileName,     ///< File name.
                 AkOpenMode              in_eOpenMode,       ///< Open mode.
                 AkFileSystemFlags *     in_pFlags,          ///< Special flags. Can pass NULL.
                 bool &                  io_bSyncOpen,       ///< If true, the file must be opened synchronously. Otherwise it is left at the File Location Resolver's discretion. Return false if Open needs to be deferred.
                 AkFileDesc &            io_fileDesc         ///< Returned file descriptor.
                 ) = 0;
  
             /// Returns a file descriptor for a given file ID.
             /// Performs the operations needed to make the file descriptor usable by
             /// the other methods of the interface (for e.g. ask the OS for a valid file handle).
             /// \return 
             ///     - AK_Success:       A valid file descriptor is returned
             ///     - AK_FileNotFound:  File was not found.
             ///     - AK_Fail:          File could not be open for any other reason.
             /// \return 
             ///     - A file descriptor, that contains 
             ///         - an unique identifier to be used with functions of the low-level IO 
             ///           interface.
             ///         - the total stream size in bytes.
             ///         - the offset from the beginning of the file (in blocks).
             ///         - a device ID, that was obtained through AK::StreamMgr::CreateDevice().
             ///     - The updated io_bSyncOpen flag depending on the File Resolver's deferred opening policy.
             /// \remarks
             ///     - Open() is always called first in the client thread.
             ///     - If io_bSyncOpen is true, file opening must be executed now. If it is false,
             ///     the File Location Resolver may choose whether it wants open it now, or later
             ///     from the streaming device's thread. If it wishes to open it now, then it must
             ///     set io_bSyncOpen to true. Otherwise, it needs to do the following: leave 
             ///     io_bSyncOpen to false, clear out_fileDesc::iFileSize and out_fileDesc::uSector, 
             ///     and set out_fileDesc::deviceID to the streaming device's ID that will handle 
             ///     this file. By returning io_bSyncOpen as false, the Stream Manager will interpret
             ///     this as a request for deferred file opening, and this function will called again
             ///     from the streaming device's thread (this time, with this io_bSyncOpen set to true).
             ///     - All members of out_fileDesc will be cleared upon first call to Open().
             /// \warning
             ///     - It is illegal to return io_bSyncOpen as false if Open() was called with io_bSyncOpen
             ///     set to true.
             ///     - Deferred file opening requires allocations in the Stream Manager's small object pool.
             ///     The File Location Resolver should always choose to open files synchronously if it is 
             ///     fast to do so.
             ///     - Whether opening is deferred or not, GetBlockSize() is always called right after the
             ///     first call to Open(), in the client's thread, and is never called again.
             /// - GetBlockSize()
             /// - \ref streamingmanager_lowlevel_location
             virtual AKRESULT Open( 
                 AkFileID                in_fileID,          ///< File ID.
                 AkOpenMode              in_eOpenMode,       ///< Open mode.
                 AkFileSystemFlags *     in_pFlags,          ///< Special flags. Can pass NULL.
                 bool &                  io_bSyncOpen,       ///< If true, the file must be opened synchronously. Otherwise it is left at the File Location Resolver's discretion. Return false if Open needs to be deferred.
                 AkFileDesc &            io_fileDesc         ///< Returned file descriptor.
                 ) = 0;
  
             /// <summary>
             /// This function is called to provide information when file related errors occur. The base paths known by this Resolver should be returned in out_searchedPath.
             /// </summary>          
             virtual AKRESULT OutputSearchedPaths(
                 const AKRESULT& in_result,              ///< Result of the open call
                 const AkOSChar* in_pszFileName,         ///< File name that was accessed
                 AkFileSystemFlags* in_pFlags,           ///< Special flags. Can be NULL.
                 AkOpenMode in_eOpenMode,                ///< File open mode (read, write, ...).
                 AkOSChar* out_searchedPath,             ///< Pre-allocated string buffer to be filled with all searched paths searched for the file.
                 AkInt32 in_pathSize                     ///< The maximum size of the string
             ) { return AK_NotImplemented; };
  
             virtual AKRESULT OutputSearchedPaths(
                 const AKRESULT& in_result,              ///< Result of the open call
                 const AkFileID in_fileID,               ///< File ID that was accessed
                 AkFileSystemFlags* in_pFlags,           ///< Special flags. Can be NULL.
                 AkOpenMode in_eOpenMode,                ///< File open mode (read, write, ...).
                 AkOSChar* out_searchedPath,             ///< Pre-allocated string buffer to be filled with all searched paths searched for the file.
                 AkInt32 in_pathSize                     ///< The maximum size of the string
             ) { return AK_NotImplemented; };
         };
  
         /// \name Audiokinetic implementation-specific Stream Manager factory.
         //@{
         /// Stream Manager factory.
         /// \remarks 
         /// - In order for the Stream Manager to work properly, you also need to create 
         /// at least one streaming device (and implement its I/O hook), and register the 
         /// File Location Resolver with AK::StreamMgr::SetFileLocationResolver().
         /// - Use AK::StreamMgr::GetDefaultSettings(), then modify the settings you want,
         /// then feed this function with them.
         /// \sa 
         /// - AK::IAkStreamMgr
         /// - AK::StreamMgr::SetFileLocationResolver()
         /// - AK::StreamMgr::GetDefaultSettings()
         AK_EXTERNAPIFUNC( IAkStreamMgr *, Create )( 
             const AkStreamMgrSettings & in_settings     ///< Stream manager initialization settings.
             );
  
         /// Get the default values for the Stream Manager's settings.
         /// \sa 
         /// - AK::StreamMgr::Create()
         /// - AkStreamMgrSettings
         /// - \ref streamingmanager_settings
         AK_EXTERNAPIFUNC( void, GetDefaultSettings )(
             AkStreamMgrSettings &       out_settings    ///< Returned AkStreamMgrSettings structure with default values.
             );
  
         /// Get the one and only File Location Resolver registered to the Stream Manager.
         /// \sa
         /// - AK::StreamMgr::IAkFileLocationResolver
         /// - AK::StreamMgr::SetFileLocationResolver()
         AK_EXTERNAPIFUNC( IAkFileLocationResolver *, GetFileLocationResolver )();
  
         /// Register the one and only File Location Resolver to the Stream Manager.
         /// \sa 
         /// - AK::StreamMgr::IAkFileLocationResolver
         AK_EXTERNAPIFUNC( void, SetFileLocationResolver )(
             IAkFileLocationResolver *   in_pFileLocationResolver ///< Interface to your File Location Resolver
             );
  
         //@}
  
         /// \name Stream Manager: High-level I/O devices management.
         //@{
         /// Streaming device creation.
         /// Creates a high-level device, with specific settings. 
         /// You need to provide the associated low-level I/O hook, implemented on your side.
         /// \return The device ID. AK_INVALID_DEVICE_ID if there was an error and it could not be created.
         /// \warning 
         /// - This function is not thread-safe.
         /// - Use a blocking hook (IAkIOHookBlocking) with SCHEDULER_BLOCKING devices, and a 
         /// deferred hook (IAkIOHookDeferredBatch) with SCHEDULER_DEFERRED_LINED_UP devices (these flags are
         /// specified in the device settings (AkDeviceSettings). The pointer to IAkLowLevelIOHook is
         /// statically cast internally into one of these hooks. Implementing the wrong (or no) interface
         /// will result into a crash.
         /// \remarks 
         /// - You may use AK::StreamMgr::GetDefaultDeviceSettings() first to get default values for the 
         /// settings, change those you want, then feed the structure to this function.
         /// - The returned device ID should be kept by the Low-Level IO, to assign it to file descriptors 
         /// in AK::StreamMgr::IAkFileLocationResolver::Open().
         /// \sa
         /// - AK::StreamMgr::IAkLowLevelIOHook
         /// - AK::StreamMgr::GetDefaultDeviceSettings()
         /// - \ref streamingmanager_settings
         AK_EXTERNAPIFUNC( AkDeviceID, CreateDevice )(
             const AkDeviceSettings &    in_settings,        ///< Device settings.
             IAkLowLevelIOHook *         in_pLowLevelHook    ///< Associated low-level I/O hook. Pass either a IAkIOHookBlocking or a IAkIOHookDeferredBatch interface, consistent with the type of the scheduler.
             );
         /// Streaming device destruction.
         /// \return AK_Success if the device was successfully destroyed.
         /// \warning This function is not thread-safe. No stream should exist for that device when it is destroyed.
         AK_EXTERNAPIFUNC( AKRESULT, DestroyDevice )(
             AkDeviceID                  in_deviceID         ///< Device ID of the device to destroy.
             );
         
         /// Execute pending I/O operations on all created I/O devices.
         /// This should only be called in single-threaded environments where an I/O device cannot spawn a thread.
         /// \return AK_Success when called from an appropriate environment, AK_NotCompatible otherwise.
         /// \sa 
         /// - AK::StreamMgr::CreateDevice()
         AK_EXTERNAPIFUNC( AKRESULT, PerformIO )();
  
         /// Get the default values for the streaming device's settings. Recommended usage
         /// is to call this function first, then pass the settings to AK::StreamMgr::CreateDevice().
         /// \sa 
         /// - AK::StreamMgr::CreateDevice()
         /// - AkDeviceSettings
         /// - \ref streamingmanager_settings
         AK_EXTERNAPIFUNC( void, GetDefaultDeviceSettings )(
             AkDeviceSettings &          out_settings        ///< Returned AkDeviceSettings structure with default values.
             );
         //@}
  
         /// \name Language management.
         //@{
         /// Set the current language once and only once, here. The language name is stored in a static buffer 
         /// inside the Stream Manager. In order to resolve localized (language-specific) file location,
         /// AK::StreamMgr::IAkFileLocationResolver implementations query this string. They may use it to 
         /// construct a file path (for e.g. SDK/samples/SoundEngine/Common/AkFileLocationBase.cpp), or to
         /// find a language-specific file within a look-up table (for e.g. SDK/samples/SoundEngine/Common/AkFilePackageLUT.cpp).
         /// Pass a valid null-terminated string, without a trailing slash or backslash. Empty strings are accepted.
         /// You may register for language changes (see RegisterToLanguageChangeNotification()). 
         /// After changing the current language, all observers are notified.
         /// \return AK_Success if successful (if language string has less than AK_MAX_LANGUAGE_NAME_SIZE characters). AK_Fail otherwise.
         /// \warning Not multithread safe.
         /// \sa 
         /// - AK::StreamMgr::GetCurrentLanguage()
         /// - AK::StreamMgr::AddLanguageChangeObserver()
         AK_EXTERNAPIFUNC( AKRESULT, SetCurrentLanguage )(
             const AkOSChar *    in_pszLanguageName          ///< Language name.
             );
  
         /// Get the current language. The language name is stored in a static buffer inside the Stream Manager, 
         /// with AK::StreamMgr::SetCurrentLanguage(). In order to resolve localized (language-specific) file location,
         /// AK::StreamMgr::IAkFileLocationResolver implementations query this string. They may use it to 
         /// construct a file path (for e.g. SDK/samples/SoundEngine/Common/AkFileLocationBase.cpp), or to
         /// find a language-specific file within a look-up table (for e.g. SDK/samples/SoundEngine/Common/AkFilePackageLUT.cpp).
         /// \return Current language.
         /// \sa AK::StreamMgr::SetCurrentLanguage()
         AK_EXTERNAPIFUNC( const AkOSChar *, GetCurrentLanguage )();
  
         /// Definition of handlers for language change notifications.
         /// Called after SetCurrentLanguage() is called.
         /// \warning Do not call AddLanguageChangeObserver or SetCurrentLanguage from within your handler.
         /// \warning Not multithread safe.
         /// \sa 
         /// - AK::StreamMgr::SetCurrentLanguage()
         /// - AK::StreamMgr::AddLanguageChangeObserver()
         AK_CALLBACK( void, AkLanguageChangeHandler )( 
             const AkOSChar * const in_pLanguageName,///< New language name.
             void * in_pCookie                       ///< Cookie that was passed to AddLanguageChangeObserver().
             );
  
         /// Register to language change notifications.
         /// \return AK_Success if successful, AK_Fail otherwise (no memory or no cookie).
         /// \warning Not multithread safe.
         /// \sa 
         /// - AK::StreamMgr::SetCurrentLanguage()
         /// - AK::StreamMgr::RemoveLanguageChangeObserver()
         AK_EXTERNAPIFUNC( AKRESULT, AddLanguageChangeObserver )(
             AkLanguageChangeHandler in_handler, ///< Callback function.
             void * in_pCookie                   ///< Cookie, passed back to AkLanguageChangeHandler. Must set.
             );
  
         /// Unregister to language change notifications. Use the cookie you have passed to 
         /// AddLanguageChangeObserver() to identify the observer.
         /// \warning Not multithread safe.
         /// \sa 
         /// - AK::StreamMgr::SetCurrentLanguage()
         /// - AK::StreamMgr::AddLanguageChangeObserver()
         AK_EXTERNAPIFUNC( void, RemoveLanguageChangeObserver )(
             void * in_pCookie                   ///< Cookie that was passed to AddLanguageChangeObserver().
             );
  
         /// \name Stream Manager: Cache management.
         //@{
         /// Flush cache of all devices. This function has no effect for devices where
         /// AkDeviceSettings::bUseStreamCache was set to false (no caching).
         /// \sa
         /// - \ref streamingmanager_settings
         AK_EXTERNAPIFUNC( void, FlushAllCaches )();
         
         //@}
     }
 }
  
 #endif //_AK_STREAM_MGR_MODULE_H_

AkAsyncIOTransferInfo::pCookie

void * pCookie

Reserved. The I/O device uses this cookie to retrieve the owner of the transfer.

Definition: AkStreamMgrModule.h:156

AK::StreamMgr::IAkIOHookDeferred::~IAkIOHookDeferred

virtual ~IAkIOHookDeferred()

Virtual destructor on interface to avoid warnings.

Definition: AkStreamMgrModule.h:448

AK::StreamMgr::IAkIOHookDeferredBatch::BatchWrite

virtual AKRESULT BatchWrite(AkUInt32 in_uNumTransfers, BatchIoTransferItem *in_pTransferItems, AkBatchIOCallback in_pBatchIoCallback, AKRESULT *io_pDispatchResults)=0

AkDeviceSettings::uIOMemoryAlignment

AkUInt32 uIOMemoryAlignment

I/O memory alignment. It is passed directly to AK::MemoryMgr::Malign().

Definition: AkStreamMgrModule.h:66

AK::StreamMgr::IAkLowLevelIOHook

Base interface for Low-Level I/O hooks. Defines common methods across both types of hooks.

Definition: AkStreamMgrModule.h:184

AkIoHeuristics::fDeadline

AkReal32 fDeadline

Operation deadline (ms).

Definition: AkStreamMgrModule.h:169

Audiokinetic namespace

Definition: AkWwiseSDKVersion.cs:31

AkFileDesc::pCustomParam

void * pCustomParam

Custom parameter

Definition: AkStreamMgrModule.h:98

AK_Fail

@ AK_Fail

The operation failed.

Definition: AkTypes.h:202

AkAsyncIOTransferInfo

Definition: AkStreamMgrModule.h:153

AkThreadProperties

Definition: AkPlatformFuncs.h:47

AkFileDesc

Definition: AkStreamMgrModule.h:91

AK::StreamMgr::DestroyDevice

AKSOUNDENGINE_API AKRESULT DestroyDevice(AkDeviceID in_deviceID)

AK::StreamMgr::SetCurrentLanguage

AKSOUNDENGINE_API AKRESULT SetCurrentLanguage(const AkOSChar *in_pszLanguageName)

AK::StreamMgr::IAkFileLocationResolver::Open

virtual AKRESULT Open(const AkOSChar *in_pszFileName, AkOpenMode in_eOpenMode, AkFileSystemFlags *in_pFlags, bool &io_bSyncOpen, AkFileDesc &io_fileDesc)=0

AK::StreamMgr::IAkLowLevelIOHook::GetDeviceData

virtual AkUInt32 GetDeviceData()=0

AK::StreamMgr::AkLanguageChangeHandler

void(* AkLanguageChangeHandler)(const AkOSChar *const in_pLanguageName, void *in_pCookie)

Definition: AkStreamMgrModule.h:857

AkDeviceSettings::uMaxCachePinnedBytes

AkUInt32 uMaxCachePinnedBytes

Maximum number of bytes that can be "pinned" using AK::SoundEngine::PinEventInStreamCache() or AK::IA...

Definition: AkStreamMgrModule.h:74

AkAsyncIOTransferInfo::pUserData

void * pUserData

Custom user data.

Definition: AkStreamMgrModule.h:157

AK::StreamMgr::IAkIOHookDeferredBatch::BatchIoTransferItem::pTransferInfo

AkAsyncIOTransferInfo * pTransferInfo

Definition: AkStreamMgrModule.h:315

AkIOTransferInfo::uRequestedSize

AkUInt32 uRequestedSize

Exact number of requested bytes for this transfer. Always equal to or smaller than uBufferSize.

Definition: AkStreamMgrModule.h:110

AK::StreamMgr::IAkIOHookDeferredBatch::BatchCancel

virtual void BatchCancel(AkUInt32 in_uNumTransfers, BatchIoTransferItem *in_pTransferItems, bool **io_ppbCancelAllTransfersForThisFile)=0

AK::IAkStreamMgr

Definition: IAkStreamMgr.h:687

AK_EXTERNAPIFUNC

#define AK_EXTERNAPIFUNC(_type, _name)

Definition: AkSoundEngineExport.h:81

AkDeviceSettings::uMaxConcurrentIO

AkUInt32 uMaxConcurrentIO

Maximum number of transfers that can be sent simultaneously to the Low-Level I/O.

Definition: AkStreamMgrModule.h:72

AkDeviceSettings::fTargetAutoStmBufferLength

AkReal32 fTargetAutoStmBufferLength

Targetted automatic stream buffer length (ms). When a stream reaches that buffering,...

Definition: AkStreamMgrModule.h:71

AkDeviceSettings::bUseStreamCache

bool bUseStreamCache

If true, the device attempts to reuse I/O buffers that have already been streamed from disk....

Definition: AkStreamMgrModule.h:73

AK::StreamMgr::GetDefaultSettings

AKSOUNDENGINE_API void GetDefaultSettings(AkStreamMgrSettings &out_settings)

AK::StreamMgr::IAkFileLocationResolver::OutputSearchedPaths

virtual AKRESULT OutputSearchedPaths(const AKRESULT &in_result, const AkFileID in_fileID, AkFileSystemFlags *in_pFlags, AkOpenMode in_eOpenMode, AkOSChar *out_searchedPath, AkInt32 in_pathSize)

Definition: AkStreamMgrModule.h:720

AKRESULT

Standard function call result.

Definition: AkTypes.h:199

AK::StreamMgr::IAkLowLevelIOHook::~IAkLowLevelIOHook

virtual ~IAkLowLevelIOHook()

Virtual destructor on interface to avoid warnings.

Definition: AkStreamMgrModule.h:187

AkDeviceID

AkUInt32 AkDeviceID

I/O device ID

Definition: AkTypes.h:146

AK::StreamMgr::IAkFileLocationResolver::Open

virtual AKRESULT Open(AkFileID in_fileID, AkOpenMode in_eOpenMode, AkFileSystemFlags *in_pFlags, bool &io_bSyncOpen, AkFileDesc &io_fileDesc)=0

AkFileDesc::deviceID

AkDeviceID deviceID

Device ID, obtained from CreateDevice()

Definition: AkStreamMgrModule.h:100

AkIoHeuristics::priority

AkPriority priority

Operation priority (at the time it was scheduled and sent to the Low-Level I/O). Range is [AK_MIN_PRI...

Definition: AkStreamMgrModule.h:170

AkIOCallback

void(* AkIOCallback)(AkAsyncIOTransferInfo *in_pTransferInfo, AKRESULT in_eResult)

Definition: AkStreamMgrModule.h:124

AkOSChar

char AkOSChar

Generic character string

Definition: AkTypes.h:60

AkDeviceSettings::uSchedulerTypeFlags

AkUInt32 uSchedulerTypeFlags

Scheduler type flags.

Definition: AkStreamMgrModule.h:69

AkDeviceSettings::ePoolAttributes

AkUInt32 ePoolAttributes

Attributes for I/O memory. Here, specify the allocation type (AkMemType_Device, and so on)....

Definition: AkStreamMgrModule.h:67

AkDeviceSettings

Definition: AkStreamMgrModule.h:61

AK::StreamMgr::IAkIOHookDeferredBatch::~IAkIOHookDeferredBatch

virtual ~IAkIOHookDeferredBatch()

Virtual destructor on interface to avoid warnings.

Definition: AkStreamMgrModule.h:308

AkIOTransferInfo::uBufferSize

AkUInt32 uBufferSize

Size of the buffer in which the I/O hook can write to.

Definition: AkStreamMgrModule.h:109

AK::StreamMgr::IAkIOHookDeferred::Cancel

virtual void Cancel(AkFileDesc &in_fileDesc, AkAsyncIOTransferInfo &io_transferInfo, bool &io_bCancelAllTransfersForThisFile)=0

AkReal32

float AkReal32

32-bit floating point

Definition: AkNumeralTypes.h:46

AK_Success

@ AK_Success

The operation was successful.

Definition: AkTypes.h:201

AkFileHandle

FILE * AkFileHandle

File handle

Definition: AkTypes.h:77

AkInt32

int32_t AkInt32

Signed 32-bit integer

Definition: AkNumeralTypes.h:43

AkAsyncIOTransferInfo::pBuffer

void * pBuffer

Buffer for data transfer.

Definition: AkStreamMgrModule.h:154

AkFileID

AkUInt32 AkFileID

Integer-type file identifier

Definition: AkTypes.h:145

IAkStreamMgr.h

AK::StreamMgr::CreateDevice

AKSOUNDENGINE_API AkDeviceID CreateDevice(const AkDeviceSettings &in_settings, IAkLowLevelIOHook *in_pLowLevelHook)

AkDeviceSettings::uGranularity

AkUInt32 uGranularity

I/O requests granularity (typical bytes/request).

Definition: AkStreamMgrModule.h:68

AkIoHeuristics

Definition: AkStreamMgrModule.h:168

AK::StreamMgr::IAkIOHookDeferred::BatchCancel

virtual void BatchCancel(AkUInt32 in_uNumTransfers, BatchIoTransferItem *in_pTransferItems, bool **io_ppbCancelAllTransfersForThisFile)

Definition: AkStreamMgrModule.h:576

AK::StreamMgr::IAkIOHookDeferred::BatchWrite

virtual AKRESULT BatchWrite(AkUInt32 in_uNumTransfers, BatchIoTransferItem *in_pTransferItems, AkBatchIOCallback, AKRESULT *io_pDispatchResults)

Definition: AkStreamMgrModule.h:559

AK::StreamMgr::IAkLowLevelIOHook::GetDeviceDesc

virtual void GetDeviceDesc(AkDeviceDesc &out_deviceDesc)=0

AK::StreamMgr::PerformIO

AKSOUNDENGINE_API AKRESULT PerformIO()

AK::StreamMgr::IAkIOHookDeferredBatch::BatchIoTransferItem::pFileDesc

AkFileDesc * pFileDesc

Definition: AkStreamMgrModule.h:313

AkPriority

AkInt8 AkPriority

Priority

Definition: AkTypes.h:135

AkFileDesc::pPackage

CAkFilePackage * pPackage

If this file is in a File Package, this will be the

Definition: AkStreamMgrModule.h:101

AkPlatformFuncs.h

AK_CALLBACK

#define AK_CALLBACK(_type, _name)

Definition: AkSoundEngineExport.h:87

AK_NotImplemented

@ AK_NotImplemented

This feature is not implemented.

Definition: AkTypes.h:200

AkFileDesc::uSector

AkUInt64 uSector

Definition: AkStreamMgrModule.h:93

AkFileSystemFlags

File system flags for file descriptors mapping.

Definition: IAkStreamMgr.h:81

AK::StreamMgr::IAkLowLevelIOHook::GetBlockSize

virtual AkUInt32 GetBlockSize(AkFileDesc &in_fileDesc)=0

AkIOTransferInfo

Definition: AkStreamMgrModule.h:107

AkInt64

int64_t AkInt64

Signed 64-bit integer

Definition: AkNumeralTypes.h:44

AK::StreamMgr::IAkLowLevelIOHook::Close

virtual AKRESULT Close(AkFileDesc &in_fileDesc)=0

AkAsyncIOTransferInfo::pCallback

AkIOCallback pCallback

Callback function used to notify the high-level device when the transfer is complete.

Definition: AkStreamMgrModule.h:155

AK::StreamMgr::IAkIOHookDeferred::Read

virtual AKRESULT Read(AkFileDesc &in_fileDesc, const AkIoHeuristics &in_heuristics, AkAsyncIOTransferInfo &io_transferInfo)=0

AkUInt64

uint64_t AkUInt64

Unsigned 64-bit integer

Definition: AkNumeralTypes.h:39

AK::StreamMgr::GetFileLocationResolver

AKSOUNDENGINE_API IAkFileLocationResolver * GetFileLocationResolver()

AK::StreamMgr::IAkIOHookDeferredBatch::BatchRead

virtual AKRESULT BatchRead(AkUInt32 in_uNumTransfers, BatchIoTransferItem *in_pTransferItems, AkBatchIOCallback in_pBatchIoCallback, AKRESULT *io_pDispatchResults)=0

AK::StreamMgr::Create

AKSOUNDENGINE_API IAkStreamMgr * Create(const AkStreamMgrSettings &in_settings)

AK::StreamMgr::FlushAllCaches

AKSOUNDENGINE_API void FlushAllCaches()

AkOpenMode

File open mode.

Definition: IAkStreamMgr.h:72

AK::StreamMgr::IAkIOHookBlocking

Definition: AkStreamMgrModule.h:244

AkDeviceDesc

Device descriptor.

Definition: IAkStreamMgr.h:153

AK::StreamMgr::IAkIOHookBlocking::Write

virtual AKRESULT Write(AkFileDesc &in_fileDesc, const AkIoHeuristics &in_heuristics, void *in_pData, AkIOTransferInfo &io_transferInfo)=0

AK::StreamMgr::IAkFileLocationResolver::OutputSearchedPaths

virtual AKRESULT OutputSearchedPaths(const AKRESULT &in_result, const AkOSChar *in_pszFileName, AkFileSystemFlags *in_pFlags, AkOpenMode in_eOpenMode, AkOSChar *out_searchedPath, AkInt32 in_pathSize)

This function is called to provide information when file related errors occur. The base paths known b...

Definition: AkStreamMgrModule.h:711

AK::StreamMgr::GetDefaultDeviceSettings

AKSOUNDENGINE_API void GetDefaultDeviceSettings(AkDeviceSettings &out_settings)

AK::StreamMgr::IAkIOHookBlocking::Read

virtual AKRESULT Read(AkFileDesc &in_fileDesc, const AkIoHeuristics &in_heuristics, void *out_pBuffer, AkIOTransferInfo &in_transferInfo)=0

AK::StreamMgr::IAkIOHookDeferredBatch

Definition: AkStreamMgrModule.h:305

AkBatchIOCallback

void(* AkBatchIOCallback)(AkUInt32 in_uNumTransfers, AkAsyncIOTransferInfo **in_ppTransferInfo, AKRESULT *in_peResult)

Definition: AkStreamMgrModule.h:141

AK::StreamMgr::SetFileLocationResolver