146 lines
5.4 KiB
C
146 lines
5.4 KiB
C
/*
|
|
*******************************************************************************
|
|
* *
|
|
* COPYRIGHT: *
|
|
* (C) Copyright International Business Machines Corporation, 1998 *
|
|
* Licensed Material - Program-Property of IBM - All Rights Reserved. *
|
|
* US Government Users Restricted Rights - Use, duplication, or disclosure *
|
|
* restricted by GSA ADP Schedule Contract with IBM Corp. *
|
|
* *
|
|
*******************************************************************************
|
|
*
|
|
* File scsu.h
|
|
*
|
|
* Modification History:
|
|
*
|
|
* Date Name Description
|
|
* 05/17/99 stephen Creation (ported from java UnicodeCompressor.java)
|
|
* 09/21/99 stephen Updated to handle data splits on decompression.
|
|
*******************************************************************************
|
|
*/
|
|
|
|
#ifndef SCSU_H
|
|
#define SCSU_H 1
|
|
|
|
#include "utypes.h"
|
|
|
|
/* Number of windows */
|
|
#define USCSU_NUM_WINDOWS 8
|
|
#define USCSU_NUM_STATIC_WINDOWS 8
|
|
|
|
/* Maximum value for a window's index */
|
|
#define USCSU_MAX_INDEX 0xFF
|
|
|
|
/** The size of the internal buffer for a UnicodeCompressor */
|
|
#define USCSU_BUFSIZE 3
|
|
|
|
/** The UnicodeCompressor struct */
|
|
struct UnicodeCompressor {
|
|
|
|
/** Alias to current dynamic window */
|
|
int32_t fCurrentWindow;
|
|
|
|
/** Dynamic compression window offsets */
|
|
int32_t fOffsets [ USCSU_NUM_WINDOWS ];
|
|
|
|
/** Current compression mode */
|
|
int32_t fMode;
|
|
|
|
/** Keeps count of times character indices are encountered */
|
|
int32_t fIndexCount [ USCSU_MAX_INDEX + 1 ];
|
|
|
|
/** The time stamps indicate when a window was last defined */
|
|
int32_t fTimeStamps [ USCSU_NUM_WINDOWS ];
|
|
|
|
/** The current time stamp */
|
|
int32_t fTimeStamp;
|
|
|
|
/** Internal buffer for saving state */
|
|
uint8_t fBuffer [ USCSU_BUFSIZE ];
|
|
|
|
/** Number of characters in our internal buffer */
|
|
int32_t fBufferLength;
|
|
};
|
|
typedef struct UnicodeCompressor UnicodeCompressor;
|
|
|
|
/**
|
|
* Initialize a UnicodeCompressor.
|
|
* Sets all windows to their default values.
|
|
* @see #reset
|
|
*/
|
|
U_CAPI void U_EXPORT2 scsu_init(UnicodeCompressor *comp);
|
|
|
|
/**
|
|
* Reset the compressor to its initial state.
|
|
* @param comp The UnicodeCompressor to reset.
|
|
*/
|
|
U_CAPI void U_EXPORT2 scsu_reset(UnicodeCompressor *comp);
|
|
|
|
/**
|
|
* Compress a Unicode character array into a byte array.
|
|
*
|
|
* This function is not guaranteed to completely fill the output buffer, nor
|
|
* is it guaranteed to compress the entire input.
|
|
* If the source data is completely compressed, <TT>status</TT> will be set
|
|
* to <TT>U_ZERO_ERROR</TT>.
|
|
* If the source data is not completely compressed, <TT>status</TT> will be
|
|
* set to <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT>. If this occurs, larger buffers
|
|
* should be allocated, or data flushed, and the function should be called
|
|
* again with the new buffers.
|
|
*
|
|
* @param comp A pointer to a previously-initialized UnicodeCompressor
|
|
* @param target I/O parameter. On input, a pointer to a buffer of bytes to
|
|
* receive the compressed data. On output, points to the byte following
|
|
* the last byte written. This buffer must be at least 4 bytes.
|
|
* @param targetLimit A pointer to the end of the array <TT>target</TT>.
|
|
* @param source I/O parameter. On input, a pointer to a buffer of
|
|
* Unicode characters to be compressed. On output, points to the character
|
|
* following the last character compressed.
|
|
* @param sourceLimit A pointer to the end of the array <TT>source</TT>.
|
|
* @param status A pointer to an UErrorCode to receive any errors.
|
|
*
|
|
* @see #decompress
|
|
*/
|
|
U_CAPI void U_EXPORT2 scsu_compress(UnicodeCompressor *comp,
|
|
uint8_t **target,
|
|
const uint8_t *targetLimit,
|
|
const UChar **source,
|
|
const UChar *sourceLimit,
|
|
UErrorCode *status);
|
|
|
|
/**
|
|
* Decompress a byte array into a Unicode character array.
|
|
*
|
|
* This function will either completely fill the output buffer, or
|
|
* consume the entire input.
|
|
* If the source data is completely compressed, <TT>status</TT> will be set
|
|
* to <TT>U_ZERO_ERROR</TT>.
|
|
* If the source data is not completely compressed, <TT>status</TT> will be
|
|
* set to <TT>U_INDEX_OUTOFBOUNDS_ERROR</TT>. If this occurs, larger buffers
|
|
* should be allocated, or data flushed, and the function should be called
|
|
* again with the new buffers.
|
|
*
|
|
* @param comp A pointer to a previously-initialized UnicodeDecompressor
|
|
* @param target I/O parameter. On input, a pointer to a buffer of Unicode
|
|
* characters to receive the compressed data. On output, points to the
|
|
* character following the last character written. This buffer must be
|
|
* at least 2 bytes.
|
|
* @param targetLimit A pointer to the end of the array <TT>target</TT>.
|
|
* @param source I/O parameter. On input, a pointer to a buffer of
|
|
* bytes to be decompressed. On output, points to the byte following the
|
|
* last byte decompressed.
|
|
* @param sourceLimit A pointer to the end of the array <TT>source</TT>.
|
|
* @param status A pointer to an UErrorCode to receive any errors.
|
|
* @return The number of Unicode characters writeten to <TT>target</TT>.
|
|
*
|
|
* @see #compress
|
|
*/
|
|
U_CAPI void U_EXPORT2 scsu_decompress(UnicodeCompressor *comp,
|
|
UChar **target,
|
|
const UChar *targetLimit,
|
|
const uint8_t **source,
|
|
const uint8_t *sourceLimit,
|
|
UErrorCode *status);
|
|
|
|
#endif
|