Windows-Server-2003/ds/xpress/xpress.h

192 lines
6.6 KiB
C

#ifndef _XPRESS_H_
#define _XPRESS_H_
#ifdef _MSC_VER
#pragma once
#endif
/* ------------------------------------------------------------------------ */
/* */
/* Copyright (c) Microsoft Corporation, 2000-2002. All rights reserved. */
/* Copyright (c) Andrew Kadatch, 1991-2002. All rights reserved. */
/* */
/* Microsoft Confidential -- do not redistribute. */
/* */
/* ------------------------------------------------------------------------ */
#ifdef __cplusplus
extern "C" {
#endif
/* ---------------------- Common declarations ------------------------- */
/* ------------------- */
// max. size of input block
#define XPRESS_MAX_BLOCK_LOG 16
#define XPRESS_MAX_BLOCK (1 << XPRESS_MAX_BLOCK_LOG)
// preferred data alignment to avoid misaligned accesses
#define XPRESS_ALIGNMENT 8
// declare default calling convention used in xpress
#if !defined (UNIX) && !defined (XPRESS_CALL)
#define XPRESS_CALL __stdcall
#endif
#if !defined (XPRESS_EXPORT)
#define XPRESS_EXPORT
#endif
// user-supplied callback function that allocates memory
// if there is no memory available it shall return NULL
typedef
void *
XPRESS_CALL
XpressAllocFn (
void *Context, // user-defined context (as passed to XpressEncodeCreate)
int AllocSize // size of memory block to allocate (bytes)
);
// user-supplied callback function that releases memory
typedef
void
XPRESS_CALL
XpressFreeFn (
void *Context, // user-defined context (as passed to XpressEncodeClose)
void *Address // pointer to the block to be freed
);
/* ----------------------------- Encoder ------------------------------ */
/* ------- */
// declare unique anonymous types for type safety
typedef struct {int XpressEncodeDummy;} *XpressEncodeStream;
// allocate and initialize encoder's data structures
// returns NULL if callback returned NULL (not enough memory)
XPRESS_EXPORT
XpressEncodeStream
XPRESS_CALL
XpressEncodeCreate (
int MaxOrigSize, // max size of original data block (bytes)
void *Context, // user-defined context info (will be passed to AllocFn)
XpressAllocFn *AllocFn, // memory allocation callback
int CompressionLevel // use 0 for speed, 9 for quality
);
// callback function called by XpressEncode to indicate compression progress
typedef
void
XPRESS_CALL
XpressProgressFn (
void *Context, // user-defined context
int EncodedSize // size of processed original data (bytes)
);
// returns size of compressed data
// if compression failed then compressed buffer is left as is, and
// original data should be saved instead
XPRESS_EXPORT
int
XPRESS_CALL
XpressEncode (
XpressEncodeStream EncodeStream, // encoder's workspace
void *CompAdr, // address of beggining of output memory region
int CompSize, // size of output memory region (bytes)
const void *OrigAdr, // address of beggining of input data block
int OrigSize, // input data block size (bytes)
XpressProgressFn *ProgressFn, // NULL or progress callback
void *ProgressContext, // user-defined context that will be passed to ProgressFn
int ProgressSize // call ProgressFn each time ProgressSize bytes processed
);
// returns size of compressed data
// if compression failed then compressed buffer is left as is, and
// original data should be saved instead
XPRESS_EXPORT
int
XPRESS_CALL
XpressEncodeEx (
XpressEncodeStream EncodeStream, // encoder's workspace
void *CompAdr, // address of beggining of output memory region
int CompSize, // size of output memory region (bytes)
const void *OrigAdr, // address of beggining of input data block
int OrigSize, // input data block size (bytes)
XpressProgressFn *ProgressFn, // NULL or progress callback
void *ProgressContext, // user-defined context that will be passed to ProgressFn
int ProgressSize, // call ProgressFn each time ProgressSize bytes processed
int CompressionLevel // CompressionLevel should not exceed MaxCompressionLevel
);
// returns MaxCompressionLevel or (-1) if stream was not initialized properly
XPRESS_EXPORT
int
XPRESS_CALL
XpressEncodeGetMaxCompressionLevel (
XpressEncodeStream EncodeStream // encoder's workspace
);
// invalidate encoding stream and release workspace memory
XPRESS_EXPORT
void
XPRESS_CALL
XpressEncodeClose (
XpressEncodeStream EncodeStream, // encoder's workspace
void *Context, // user-defined context for FreeFn
XpressFreeFn *FreeFn // memory release callback
);
/* ----------------------------- Decoder ------------------------------ */
/* ------- */
// declare unique anonymous types for type safety
typedef struct {int XpressDecodeDummy;} *XpressDecodeStream;
// allocate memory for decoder. Returns NULL if not enough memory.
XPRESS_EXPORT
XpressDecodeStream
XPRESS_CALL
XpressDecodeCreate (
void *Context, // user-defined context info (will be passed to AllocFn)
XpressAllocFn *AllocFn // memory allocation callback
);
// decode compressed block. Returns # of decoded bytes or -1 otherwise
XPRESS_EXPORT
int
XPRESS_CALL
XpressDecode (
XpressDecodeStream DecodeStream, // decoder's workspace
void *OrigAdr, // address of beginning out output memory region
int OrigSize, // size of output memory region (bytes)
int DecodeSize, // # of bytes to decode ( <= OrigSize)
const void *CompAdr, // address of beginning of compressed data block
int CompSize // size of compressed data block (bytes)
);
// invalidate decoding stream and release workspace memory
XPRESS_EXPORT
void
XPRESS_CALL
XpressDecodeClose (
XpressDecodeStream DecodeStream, // encoder's workspace
void *Context, // user-defined context info (will be passed to FreeFn)
XpressFreeFn *FreeFn // callback that releases the memory
);
#ifdef __cplusplus
};
#endif
#endif /* _XPRESS_H_ */