[mirror_edk2.git] / DynamicTablesPkg / Library / Common / AmlLib / Stream / AmlStream.h

/** @file\r
  AML Stream.\r
\r
  Copyright (c) 2019 - 2020, Arm Limited. All rights reserved.<BR>\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
**/\r
\r
#ifndef AML_STREAM_H_\r
#define AML_STREAM_H_\r
\r
#include <AmlInclude.h>\r
\r
/** Stream direction.\r
\r
  Enum to choose the direction the stream is progressing.\r
*/\r
typedef enum EAmlStreamDirection {\r
  EAmlStreamDirectionInvalid,     ///< Invalid AML Stream direction.\r
  EAmlStreamDirectionForward,     ///< Forward direction.\r
                                  ///  The Stream goes toward higher addresses.\r
  EAmlStreamDirectionBackward,    ///< Forward direction.\r
                                  ///  The Stream goes toward lower addresses.\r
  EAmlStreamDirectionMax,         ///< Max enum.\r
} EAML_STREAM_DIRECTION;\r
\r
/** Stream.\r
\r
  This structure is used as a wrapper around a buffer. It allows to do common\r
  buffer manipulations (read, write, etc.) while preventing buffer overflows.\r
*/\r
typedef struct AmlStream {\r
  /// Pointer to a buffer.\r
  UINT8     *Buffer;\r
\r
  /// Size of Buffer.\r
  UINT32    MaxBufferSize;\r
\r
  /// Index in the Buffer.\r
  /// The Index field allows to keep track of how many bytes have been\r
  /// read/written in the Buffer, and to retrieve the current stream position.\r
  /// 0 <= Index <= MaxBufferSize.\r
  /// If Index == MaxBufferSize, no more action is allowed on the stream.\r
  UINT32    Index;\r
\r
  /// The direction the stream is progressing.\r
  /// If the stream goes backward (toward lower addresses), the bytes written\r
  /// to the stream are not reverted.\r
  /// In the example below, writing "Hello" to the stream will not revert\r
  /// the string. The end of the stream buffer will contain "Hello world!".\r
  /// Similarly, moving the stream position will be done according to the\r
  /// direction of the stream.\r
  /// Stream buffer:\r
  ///    +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
  ///    |-------------- | ' ' | 'w' | 'o' | 'r' | 'l' | 'd' | '!' | '\0' |\r
  ///    +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
  ///                       ^\r
  ///                Current position.\r
  EAML_STREAM_DIRECTION    Direction;\r
} AML_STREAM;\r
\r
/** Check whether a StreamPtr is a valid Stream.\r
\r
  @param  [in]  Stream   Pointer to a stream.\r
\r
  @retval TRUE  Stream is a pointer to a stream.\r
  @retval FALSE Otherwise.\r
*/\r
#define IS_STREAM(Stream)  (                                                  \\r
          (((AML_STREAM*)Stream) != NULL)                                 &&  \\r
          (((AML_STREAM*)Stream)->Buffer != NULL))\r
\r
/** Check whether a Stream is at the end of its buffer.\r
\r
  @param  [in]  Stream   Pointer to a stream.\r
\r
  @retval TRUE  Stream is a pointer to a non-full stream.\r
  @retval FALSE Otherwise.\r
*/\r
#define IS_END_OF_STREAM(Stream)  (                                           \\r
          (((AML_STREAM*)Stream)->Index ==                                    \\r
             ((AML_STREAM*)Stream)->MaxBufferSize))\r
\r
/** Check Stream goes forward.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @retval TRUE  Stream goes forward.\r
  @retval FALSE Otherwise.\r
*/\r
#define IS_STREAM_FORWARD(Stream)  (                                          \\r
    ((AML_STREAM*)Stream)->Direction == EAmlStreamDirectionForward)\r
\r
/** Check Stream goes backward.\r
\r
  @param  [in]  Stream   Pointer to a stream.\r
\r
  @retval TRUE  Stream goes backward.\r
  @retval FALSE Otherwise.\r
*/\r
#define IS_STREAM_BACKWARD(Stream)  (                                         \\r
    ((AML_STREAM*)Stream)->Direction == EAmlStreamDirectionBackward)\r
\r
/** Initialize a stream.\r
\r
  @param  [in, out] Stream          Pointer to the stream to initialize.\r
  @param  [in]      Buffer          Buffer to initialize Stream with.\r
                                    Point to the beginning of the Buffer.\r
  @param  [in]      MaxBufferSize   Maximum size of Buffer.\r
  @param  [in]      Direction       Direction Stream is progressing\r
                                    (forward, backward).\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamInit (\r
  IN  OUT AML_STREAM             *Stream,\r
  IN      UINT8                  *Buffer,\r
  IN      UINT32                 MaxBufferSize,\r
  IN      EAML_STREAM_DIRECTION  Direction\r
  );\r
\r
/** Clone a stream.\r
\r
  Cloning a stream means copying all the values of the input Stream\r
  in the ClonedStream.\r
\r
  @param  [in]  Stream          Pointer to the stream to clone.\r
  @param  [in]  ClonedStream    Pointer to the stream to initialize.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamClone (\r
  IN  CONST AML_STREAM   *Stream,\r
  OUT        AML_STREAM  *ClonedStream\r
  );\r
\r
/** Initialize a sub-stream from a stream.\r
\r
  A sub-stream is a stream initialized at the current position of the input\r
  stream:\r
    - the Buffer field points to the current position of the input stream;\r
    - the Index field is set to 0;\r
    - the MaxBufferSize field is set to the remaining size of the input stream;\r
    - the direction is conserved;\r
\r
  E.g.: For a forward stream:\r
                   +----------------+----------------+\r
                   |ABCD.........XYZ|   Free Space   |\r
                   +----------------+----------------+\r
                   ^                ^                ^\r
  Stream:        Buffer          CurrPos         EndOfBuff\r
  Sub-stream:                Buffer/CurrPos      EndOfBuff\r
\r
  @param  [in]  Stream      Pointer to the stream from which a sub-stream is\r
                            created.\r
  @param  [in]  SubStream   Pointer to the stream to initialize.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamInitSubStream (\r
  IN  CONST AML_STREAM  *Stream,\r
  OUT       AML_STREAM  *SubStream\r
  );\r
\r
/** Get the buffer of a stream.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return The stream's Buffer.\r
          NULL otherwise.\r
**/\r
UINT8 *\r
EFIAPI\r
AmlStreamGetBuffer (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Get the size of Stream's Buffer.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return The Size of Stream's Buffer.\r
          Return 0 if Stream is invalid.\r
**/\r
UINT32\r
EFIAPI\r
AmlStreamGetMaxBufferSize (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Reduce the maximal size of Stream's Buffer (MaxBufferSize field).\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
  @param  [in]  Diff      Value to subtract to the Stream's MaxBufferSize.\r
                          0 < x < MaxBufferSize - Index.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamReduceMaxBufferSize (\r
  IN  AML_STREAM  *Stream,\r
  IN  UINT32      Diff\r
  );\r
\r
/** Get Stream's Index.\r
\r
  Stream's Index is incremented when writing data, reading data,\r
  or moving the position in the Stream.\r
  It can be seen as an index:\r
   - starting at the beginning of Stream's Buffer if the stream goes forward;\r
   - starting at the end of Stream's Buffer if the stream goes backward.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return Stream's Index.\r
          Return 0 if Stream is invalid.\r
**/\r
UINT32\r
EFIAPI\r
AmlStreamGetIndex (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Get Stream's Direction.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return Stream's Direction.\r
          Return EAmlStreamDirectionUnknown if Stream is invalid.\r
**/\r
EAML_STREAM_DIRECTION\r
EFIAPI\r
AmlStreamGetDirection (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Return a pointer to the current position in the stream.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return The current position in the stream.\r
          Return NULL if error.\r
**/\r
UINT8 *\r
EFIAPI\r
AmlStreamGetCurrPos (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Get the space available in the stream.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
\r
  @return Remaining space available in the stream.\r
          Zero in case of error or if the stream is at its end.\r
**/\r
UINT32\r
EFIAPI\r
AmlStreamGetFreeSpace (\r
  IN  CONST AML_STREAM  *Stream\r
  );\r
\r
/** Move Stream by Offset bytes.\r
\r
  The stream current position is moved according to the stream direction\r
  (forward, backward).\r
\r
  @param  [in]  Stream  Pointer to a stream.\r
                        The stream must not be at its end.\r
  @param  [in]  Offset  Offset to move the stream of.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
  @retval EFI_BUFFER_TOO_SMALL    No space left in the buffer.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamProgress (\r
  IN  AML_STREAM  *Stream,\r
  IN  UINT32      Offset\r
  );\r
\r
/** Rewind Stream of Offset bytes.\r
\r
  The stream current position is rewound according to the stream direction\r
  (forward, backward). A stream going forward will be rewound backward.\r
\r
  @param  [in]  Stream  Pointer to a stream.\r
  @param  [in]  Offset  Offset to rewind the stream of.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
  @retval EFI_BUFFER_TOO_SMALL    No space left in the buffer.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamRewind (\r
  IN  AML_STREAM  *Stream,\r
  IN  UINT32      Offset\r
  );\r
\r
/** Reset the Stream (move the current position to the initial position).\r
\r
  @param  [in]  Stream  Pointer to a stream.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamReset (\r
  IN  AML_STREAM  *Stream\r
  );\r
\r
/** Peek one byte at Stream's current position.\r
\r
  Stream's position is not moved when peeking.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
                          The stream must not be at its end.\r
  @param  [out] OutByte   Pointer holding the byte value of\r
                          the stream current position.\r
\r
  @retval EFI_SUCCESS           The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER Invalid parameter.\r
  @retval EFI_BUFFER_TOO_SMALL  No space left in the buffer.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamPeekByte (\r
  IN  AML_STREAM  *Stream,\r
  OUT UINT8       *OutByte\r
  );\r
\r
/** Read one byte at Stream's current position.\r
\r
  The stream current position is moved when reading.\r
\r
  @param  [in]  Stream    Pointer to a stream.\r
                          The stream must not be at its end.\r
  @param  [out] OutByte   Pointer holding the byte value of\r
                          the stream current position.\r
\r
  @retval EFI_SUCCESS           The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER Invalid parameter.\r
  @retval EFI_BUFFER_TOO_SMALL  No space left in the buffer.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamReadByte (\r
  IN  AML_STREAM  *Stream,\r
  OUT UINT8       *OutByte\r
  );\r
\r
/** Write Size bytes in the stream.\r
\r
  If the stream goes backward (toward lower addresses), the bytes written\r
  to the stream are not reverted.\r
  In the example below, writing "Hello" to the stream will not revert\r
  the string. The end of the stream buffer will contain "Hello world!".\r
  Stream buffer:\r
     +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
     |         ..... | ' ' | 'w' | 'o' | 'r' | 'l' | 'd' | '!' | '\0' |\r
     +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
                        ^\r
                 Current position.\r
\r
  @param  [in]  Stream  Pointer to a stream.\r
                        The stream must not be at its end.\r
  @param  [in]  Buffer  Pointer to the data to write.\r
  @param  [in]  Size    Number of bytes to write.\r
\r
  @retval EFI_SUCCESS             The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER   Invalid parameter.\r
  @retval EFI_BUFFER_TOO_SMALL    No space left in the buffer.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamWrite (\r
  IN        AML_STREAM  *Stream,\r
  IN  CONST UINT8       *Buffer,\r
  IN        UINT32      Size\r
  );\r
\r
/** Compare Size bytes between Stream1 and Stream2 from their\r
    respective current position.\r
\r
  Stream1 and Stream2 must go in the same direction.\r
  Stream1 and Stream2 are left unchanged.\r
\r
  @param  [in]  Stream1   First stream to compare.\r
                          The stream must not be at its end.\r
  @param  [in]  Stream2   Second stream to compare.\r
                          The stream must not be at its end.\r
  @param  [in]  Size      Number of bytes to compare.\r
                          Must be lower than the minimum remaining space of\r
                          Stream1 and Stream2.\r
                          Must be non-zero.\r
\r
  @retval TRUE  If Stream1 and Stream2 have Size bytes equal,\r
                from their respective current position.\r
                The function completed successfully.\r
  @retval FALSE Otherwise.\r
**/\r
BOOLEAN\r
EFIAPI\r
AmlStreamCmp (\r
  IN  CONST AML_STREAM  *Stream1,\r
  IN  CONST AML_STREAM  *Stream2,\r
  IN        UINT32      Size\r
  );\r
\r
/** Copy Size bytes of the stream's data to DstBuffer.\r
\r
  For a backward stream, the bytes are copied starting from the\r
  current stream position.\r
\r
  @param  [out] DstBuffer         Destination Buffer to copy the data to.\r
  @param  [in]  MaxDstBufferSize  Maximum size of DstBuffer.\r
                                  Must be non-zero.\r
  @param  [in]  Stream            Pointer to the stream to copy the data from.\r
  @param  [in]  Size              Number of bytes to copy from the stream\r
                                  buffer.\r
                                  Must be lower than MaxDstBufferSize.\r
                                  Must be lower than Stream's MaxBufferSize.\r
                                  Return success if zero.\r
\r
  @retval EFI_SUCCESS           The function completed successfully.\r
  @retval EFI_INVALID_PARAMETER Invalid parameter.\r
**/\r
EFI_STATUS\r
EFIAPI\r
AmlStreamCpyS (\r
  OUT CHAR8       *DstBuffer,\r
  IN  UINT32      MaxDstBufferSize,\r
  IN  AML_STREAM  *Stream,\r
  IN  UINT32      Size\r
  );\r
\r
#endif // AML_STREAM_H_\r
Commit	Line	Data
7f293b25 SM	1	/** @file\r
	2	AML Stream.\r
	3	\r
	4	Copyright (c) 2019 - 2020, Arm Limited. All rights reserved.<BR>\r
	5	\r
	6	SPDX-License-Identifier: BSD-2-Clause-Patent\r
	7	**/\r
	8	\r
	9	#ifndef AML_STREAM_H_\r
	10	#define AML_STREAM_H_\r
	11	\r
	12	#include <AmlInclude.h>\r
	13	\r
	14	/** Stream direction.\r
	15	\r
	16	Enum to choose the direction the stream is progressing.\r
	17	*/\r
	18	typedef enum EAmlStreamDirection {\r
	19	EAmlStreamDirectionInvalid, ///< Invalid AML Stream direction.\r
	20	EAmlStreamDirectionForward, ///< Forward direction.\r
	21	/// The Stream goes toward higher addresses.\r
	22	EAmlStreamDirectionBackward, ///< Forward direction.\r
	23	/// The Stream goes toward lower addresses.\r
	24	EAmlStreamDirectionMax, ///< Max enum.\r
	25	} EAML_STREAM_DIRECTION;\r
	26	\r
	27	/** Stream.\r
	28	\r
	29	This structure is used as a wrapper around a buffer. It allows to do common\r
	30	buffer manipulations (read, write, etc.) while preventing buffer overflows.\r
	31	*/\r
	32	typedef struct AmlStream {\r
	33	/// Pointer to a buffer.\r
731c67e1	34	UINT8 *Buffer;\r
7f293b25 SM	35	\r
7f293b25 SM	36	/// Size of Buffer.\r
731c67e1	37	UINT32 MaxBufferSize;\r
7f293b25 SM	38	\r
	39	/// Index in the Buffer.\r
	40	/// The Index field allows to keep track of how many bytes have been\r
	41	/// read/written in the Buffer, and to retrieve the current stream position.\r
	42	/// 0 <= Index <= MaxBufferSize.\r
	43	/// If Index == MaxBufferSize, no more action is allowed on the stream.\r
731c67e1	44	UINT32 Index;\r
7f293b25 SM	45	\r
	46	/// The direction the stream is progressing.\r
	47	/// If the stream goes backward (toward lower addresses), the bytes written\r
	48	/// to the stream are not reverted.\r
	49	/// In the example below, writing "Hello" to the stream will not revert\r
	50	/// the string. The end of the stream buffer will contain "Hello world!".\r
	51	/// Similarly, moving the stream position will be done according to the\r
	52	/// direction of the stream.\r
	53	/// Stream buffer:\r
	54	/// +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
	55	/// \|-------------- \| ' ' \| 'w' \| 'o' \| 'r' \| 'l' \| 'd' \| '!' \| '\0' \|\r
	56	/// +---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
	57	/// ^\r
	58	/// Current position.\r
731c67e1	59	EAML_STREAM_DIRECTION Direction;\r
7f293b25 SM	60	} AML_STREAM;\r
	61	\r
	62	/** Check whether a StreamPtr is a valid Stream.\r
	63	\r
	64	@param [in] Stream Pointer to a stream.\r
	65	\r
	66	@retval TRUE Stream is a pointer to a stream.\r
	67	@retval FALSE Otherwise.\r
	68	*/\r
	69	#define IS_STREAM(Stream) ( \\r
	70	(((AML_STREAM*)Stream) != NULL) && \\r
	71	(((AML_STREAM*)Stream)->Buffer != NULL))\r
	72	\r
	73	/** Check whether a Stream is at the end of its buffer.\r
	74	\r
	75	@param [in] Stream Pointer to a stream.\r
	76	\r
	77	@retval TRUE Stream is a pointer to a non-full stream.\r
	78	@retval FALSE Otherwise.\r
	79	*/\r
	80	#define IS_END_OF_STREAM(Stream) ( \\r
	81	(((AML_STREAM*)Stream)->Index == \\r
	82	((AML_STREAM*)Stream)->MaxBufferSize))\r
	83	\r
	84	/** Check Stream goes forward.\r
	85	\r
	86	@param [in] Stream Pointer to a stream.\r
	87	\r
	88	@retval TRUE Stream goes forward.\r
	89	@retval FALSE Otherwise.\r
	90	*/\r
731c67e1	91	#define IS_STREAM_FORWARD(Stream) ( \\r
7f293b25 SM	92	((AML_STREAM*)Stream)->Direction == EAmlStreamDirectionForward)\r
	93	\r
	94	/** Check Stream goes backward.\r
	95	\r
	96	@param [in] Stream Pointer to a stream.\r
	97	\r
	98	@retval TRUE Stream goes backward.\r
	99	@retval FALSE Otherwise.\r
	100	*/\r
731c67e1	101	#define IS_STREAM_BACKWARD(Stream) ( \\r
7f293b25 SM	102	((AML_STREAM*)Stream)->Direction == EAmlStreamDirectionBackward)\r
	103	\r
	104	/** Initialize a stream.\r
	105	\r
	106	@param [in, out] Stream Pointer to the stream to initialize.\r
	107	@param [in] Buffer Buffer to initialize Stream with.\r
	108	Point to the beginning of the Buffer.\r
	109	@param [in] MaxBufferSize Maximum size of Buffer.\r
	110	@param [in] Direction Direction Stream is progressing\r
	111	(forward, backward).\r
	112	\r
	113	@retval EFI_SUCCESS The function completed successfully.\r
	114	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	115	**/\r
	116	EFI_STATUS\r
	117	EFIAPI\r
	118	AmlStreamInit (\r
731c67e1 MK	119	IN OUT AML_STREAM *Stream,\r
	120	IN UINT8 *Buffer,\r
	121	IN UINT32 MaxBufferSize,\r
	122	IN EAML_STREAM_DIRECTION Direction\r
7f293b25 SM	123	);\r
	124	\r
	125	/** Clone a stream.\r
	126	\r
	127	Cloning a stream means copying all the values of the input Stream\r
	128	in the ClonedStream.\r
	129	\r
	130	@param [in] Stream Pointer to the stream to clone.\r
	131	@param [in] ClonedStream Pointer to the stream to initialize.\r
	132	\r
	133	@retval EFI_SUCCESS The function completed successfully.\r
	134	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	135	**/\r
	136	EFI_STATUS\r
	137	EFIAPI\r
	138	AmlStreamClone (\r
731c67e1 MK	139	IN CONST AML_STREAM *Stream,\r
731c67e1 MK	140	OUT AML_STREAM *ClonedStream\r
7f293b25 SM	141	);\r
	142	\r
	143	/** Initialize a sub-stream from a stream.\r
	144	\r
	145	A sub-stream is a stream initialized at the current position of the input\r
	146	stream:\r
	147	- the Buffer field points to the current position of the input stream;\r
	148	- the Index field is set to 0;\r
	149	- the MaxBufferSize field is set to the remaining size of the input stream;\r
	150	- the direction is conserved;\r
	151	\r
	152	E.g.: For a forward stream:\r
	153	+----------------+----------------+\r
	154	\|ABCD.........XYZ\| Free Space \|\r
	155	+----------------+----------------+\r
	156	^ ^ ^\r
	157	Stream: Buffer CurrPos EndOfBuff\r
	158	Sub-stream: Buffer/CurrPos EndOfBuff\r
	159	\r
	160	@param [in] Stream Pointer to the stream from which a sub-stream is\r
	161	created.\r
	162	@param [in] SubStream Pointer to the stream to initialize.\r
	163	\r
	164	@retval EFI_SUCCESS The function completed successfully.\r
	165	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	166	**/\r
	167	EFI_STATUS\r
	168	EFIAPI\r
	169	AmlStreamInitSubStream (\r
731c67e1 MK	170	IN CONST AML_STREAM *Stream,\r
731c67e1 MK	171	OUT AML_STREAM *SubStream\r
7f293b25 SM	172	);\r
	173	\r
	174	/** Get the buffer of a stream.\r
	175	\r
	176	@param [in] Stream Pointer to a stream.\r
	177	\r
	178	@return The stream's Buffer.\r
	179	NULL otherwise.\r
	180	**/\r
	181	UINT8 *\r
	182	EFIAPI\r
	183	AmlStreamGetBuffer (\r
731c67e1	184	IN CONST AML_STREAM *Stream\r
7f293b25 SM	185	);\r
	186	\r
	187	/** Get the size of Stream's Buffer.\r
	188	\r
	189	@param [in] Stream Pointer to a stream.\r
	190	\r
	191	@return The Size of Stream's Buffer.\r
	192	Return 0 if Stream is invalid.\r
	193	**/\r
	194	UINT32\r
	195	EFIAPI\r
	196	AmlStreamGetMaxBufferSize (\r
731c67e1	197	IN CONST AML_STREAM *Stream\r
7f293b25 SM	198	);\r
	199	\r
	200	/** Reduce the maximal size of Stream's Buffer (MaxBufferSize field).\r
	201	\r
	202	@param [in] Stream Pointer to a stream.\r
	203	@param [in] Diff Value to subtract to the Stream's MaxBufferSize.\r
	204	0 < x < MaxBufferSize - Index.\r
	205	\r
	206	@retval EFI_SUCCESS The function completed successfully.\r
	207	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	208	**/\r
	209	EFI_STATUS\r
	210	EFIAPI\r
	211	AmlStreamReduceMaxBufferSize (\r
731c67e1 MK	212	IN AML_STREAM *Stream,\r
731c67e1 MK	213	IN UINT32 Diff\r
7f293b25 SM	214	);\r
	215	\r
	216	/** Get Stream's Index.\r
	217	\r
	218	Stream's Index is incremented when writing data, reading data,\r
	219	or moving the position in the Stream.\r
	220	It can be seen as an index:\r
	221	- starting at the beginning of Stream's Buffer if the stream goes forward;\r
	222	- starting at the end of Stream's Buffer if the stream goes backward.\r
	223	\r
	224	@param [in] Stream Pointer to a stream.\r
	225	\r
	226	@return Stream's Index.\r
	227	Return 0 if Stream is invalid.\r
	228	**/\r
	229	UINT32\r
	230	EFIAPI\r
	231	AmlStreamGetIndex (\r
731c67e1	232	IN CONST AML_STREAM *Stream\r
7f293b25 SM	233	);\r
	234	\r
	235	/** Get Stream's Direction.\r
	236	\r
	237	@param [in] Stream Pointer to a stream.\r
	238	\r
	239	@return Stream's Direction.\r
	240	Return EAmlStreamDirectionUnknown if Stream is invalid.\r
	241	**/\r
	242	EAML_STREAM_DIRECTION\r
	243	EFIAPI\r
	244	AmlStreamGetDirection (\r
731c67e1	245	IN CONST AML_STREAM *Stream\r
7f293b25 SM	246	);\r
	247	\r
	248	/** Return a pointer to the current position in the stream.\r
	249	\r
	250	@param [in] Stream Pointer to a stream.\r
	251	\r
	252	@return The current position in the stream.\r
	253	Return NULL if error.\r
	254	**/\r
	255	UINT8 *\r
	256	EFIAPI\r
	257	AmlStreamGetCurrPos (\r
731c67e1	258	IN CONST AML_STREAM *Stream\r
7f293b25 SM	259	);\r
	260	\r
	261	/** Get the space available in the stream.\r
	262	\r
	263	@param [in] Stream Pointer to a stream.\r
	264	\r
	265	@return Remaining space available in the stream.\r
	266	Zero in case of error or if the stream is at its end.\r
	267	**/\r
	268	UINT32\r
	269	EFIAPI\r
	270	AmlStreamGetFreeSpace (\r
731c67e1	271	IN CONST AML_STREAM *Stream\r
7f293b25 SM	272	);\r
	273	\r
	274	/** Move Stream by Offset bytes.\r
	275	\r
	276	The stream current position is moved according to the stream direction\r
	277	(forward, backward).\r
	278	\r
	279	@param [in] Stream Pointer to a stream.\r
	280	The stream must not be at its end.\r
	281	@param [in] Offset Offset to move the stream of.\r
	282	\r
	283	@retval EFI_SUCCESS The function completed successfully.\r
	284	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	285	@retval EFI_BUFFER_TOO_SMALL No space left in the buffer.\r
	286	**/\r
	287	EFI_STATUS\r
	288	EFIAPI\r
	289	AmlStreamProgress (\r
731c67e1 MK	290	IN AML_STREAM *Stream,\r
731c67e1 MK	291	IN UINT32 Offset\r
7f293b25 SM	292	);\r
	293	\r
	294	/** Rewind Stream of Offset bytes.\r
	295	\r
	296	The stream current position is rewound according to the stream direction\r
	297	(forward, backward). A stream going forward will be rewound backward.\r
	298	\r
	299	@param [in] Stream Pointer to a stream.\r
	300	@param [in] Offset Offset to rewind the stream of.\r
	301	\r
	302	@retval EFI_SUCCESS The function completed successfully.\r
	303	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	304	@retval EFI_BUFFER_TOO_SMALL No space left in the buffer.\r
	305	**/\r
	306	EFI_STATUS\r
	307	EFIAPI\r
	308	AmlStreamRewind (\r
731c67e1 MK	309	IN AML_STREAM *Stream,\r
731c67e1 MK	310	IN UINT32 Offset\r
7f293b25 SM	311	);\r
	312	\r
	313	/** Reset the Stream (move the current position to the initial position).\r
	314	\r
	315	@param [in] Stream Pointer to a stream.\r
	316	\r
	317	@retval EFI_SUCCESS The function completed successfully.\r
	318	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	319	**/\r
	320	EFI_STATUS\r
	321	EFIAPI\r
	322	AmlStreamReset (\r
731c67e1	323	IN AML_STREAM *Stream\r
7f293b25 SM	324	);\r
	325	\r
	326	/** Peek one byte at Stream's current position.\r
	327	\r
	328	Stream's position is not moved when peeking.\r
	329	\r
	330	@param [in] Stream Pointer to a stream.\r
	331	The stream must not be at its end.\r
	332	@param [out] OutByte Pointer holding the byte value of\r
	333	the stream current position.\r
	334	\r
	335	@retval EFI_SUCCESS The function completed successfully.\r
	336	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	337	@retval EFI_BUFFER_TOO_SMALL No space left in the buffer.\r
	338	**/\r
	339	EFI_STATUS\r
	340	EFIAPI\r
	341	AmlStreamPeekByte (\r
731c67e1 MK	342	IN AML_STREAM *Stream,\r
731c67e1 MK	343	OUT UINT8 *OutByte\r
7f293b25 SM	344	);\r
	345	\r
	346	/** Read one byte at Stream's current position.\r
	347	\r
	348	The stream current position is moved when reading.\r
	349	\r
	350	@param [in] Stream Pointer to a stream.\r
	351	The stream must not be at its end.\r
	352	@param [out] OutByte Pointer holding the byte value of\r
	353	the stream current position.\r
	354	\r
	355	@retval EFI_SUCCESS The function completed successfully.\r
	356	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	357	@retval EFI_BUFFER_TOO_SMALL No space left in the buffer.\r
	358	**/\r
	359	EFI_STATUS\r
	360	EFIAPI\r
	361	AmlStreamReadByte (\r
731c67e1 MK	362	IN AML_STREAM *Stream,\r
731c67e1 MK	363	OUT UINT8 *OutByte\r
7f293b25 SM	364	);\r
	365	\r
	366	/** Write Size bytes in the stream.\r
	367	\r
	368	If the stream goes backward (toward lower addresses), the bytes written\r
	369	to the stream are not reverted.\r
	370	In the example below, writing "Hello" to the stream will not revert\r
	371	the string. The end of the stream buffer will contain "Hello world!".\r
	372	Stream buffer:\r
	373	+---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
	374	\| ..... \| ' ' \| 'w' \| 'o' \| 'r' \| 'l' \| 'd' \| '!' \| '\0' \|\r
	375	+---------------+-----+-----+-----+-----+-----+-----+---- +------+\r
	376	^\r
	377	Current position.\r
	378	\r
	379	@param [in] Stream Pointer to a stream.\r
	380	The stream must not be at its end.\r
	381	@param [in] Buffer Pointer to the data to write.\r
	382	@param [in] Size Number of bytes to write.\r
	383	\r
	384	@retval EFI_SUCCESS The function completed successfully.\r
	385	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	386	@retval EFI_BUFFER_TOO_SMALL No space left in the buffer.\r
	387	**/\r
	388	EFI_STATUS\r
	389	EFIAPI\r
	390	AmlStreamWrite (\r
731c67e1 MK	391	IN AML_STREAM *Stream,\r
	392	IN CONST UINT8 *Buffer,\r
	393	IN UINT32 Size\r
7f293b25 SM	394	);\r
	395	\r
	396	/** Compare Size bytes between Stream1 and Stream2 from their\r
	397	respective current position.\r
	398	\r
	399	Stream1 and Stream2 must go in the same direction.\r
	400	Stream1 and Stream2 are left unchanged.\r
	401	\r
	402	@param [in] Stream1 First stream to compare.\r
	403	The stream must not be at its end.\r
	404	@param [in] Stream2 Second stream to compare.\r
	405	The stream must not be at its end.\r
	406	@param [in] Size Number of bytes to compare.\r
	407	Must be lower than the minimum remaining space of\r
	408	Stream1 and Stream2.\r
	409	Must be non-zero.\r
	410	\r
	411	@retval TRUE If Stream1 and Stream2 have Size bytes equal,\r
	412	from their respective current position.\r
	413	The function completed successfully.\r
	414	@retval FALSE Otherwise.\r
	415	**/\r
	416	BOOLEAN\r
	417	EFIAPI\r
	418	AmlStreamCmp (\r
731c67e1 MK	419	IN CONST AML_STREAM *Stream1,\r
	420	IN CONST AML_STREAM *Stream2,\r
	421	IN UINT32 Size\r
7f293b25 SM	422	);\r
	423	\r
	424	/** Copy Size bytes of the stream's data to DstBuffer.\r
	425	\r
	426	For a backward stream, the bytes are copied starting from the\r
	427	current stream position.\r
	428	\r
	429	@param [out] DstBuffer Destination Buffer to copy the data to.\r
	430	@param [in] MaxDstBufferSize Maximum size of DstBuffer.\r
	431	Must be non-zero.\r
	432	@param [in] Stream Pointer to the stream to copy the data from.\r
	433	@param [in] Size Number of bytes to copy from the stream\r
	434	buffer.\r
	435	Must be lower than MaxDstBufferSize.\r
	436	Must be lower than Stream's MaxBufferSize.\r
	437	Return success if zero.\r
	438	\r
	439	@retval EFI_SUCCESS The function completed successfully.\r
	440	@retval EFI_INVALID_PARAMETER Invalid parameter.\r
	441	**/\r
	442	EFI_STATUS\r
	443	EFIAPI\r
	444	AmlStreamCpyS (\r
731c67e1 MK	445	OUT CHAR8 *DstBuffer,\r
	446	IN UINT32 MaxDstBufferSize,\r
	447	IN AML_STREAM *Stream,\r
	448	IN UINT32 Size\r
7f293b25 SM	449	);\r
	450	\r
	451	#endif // AML_STREAM_H_\r