Check in the pristine copy of ICU 4.6...

icu46/source/tools/genrb/rle.h

+/*
+*******************************************************************************
+*
+*   Copyright (C) 2000, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+*******************************************************************************
+*
+* File writejava.c
+*
+* Modification History:
+*
+*   Date        Name        Description
+*   01/11/02    Ram        Creation.
+*******************************************************************************
+*/
+
+#ifndef RLE_H
+#define RLE_H 1
+
+#include "unicode/utypes.h"
+#include "unicode/ustring.h"
+
+U_CDECL_BEGIN
+/**
+ * Construct a string representing a byte array.  Use run-length encoding.
+ * Two bytes are packed into a single char, with a single extra zero byte at
+ * the end if needed.  A byte represents itself, unless it is the
+ * ESCAPE_BYTE.  Then the following notations are possible:
+ *   ESCAPE_BYTE ESCAPE_BYTE   ESCAPE_BYTE literal
+ *   ESCAPE_BYTE n b           n instances of byte b
+ * Since an encoded run occupies 3 bytes, we only encode runs of 4 or
+ * more bytes.  Thus we have n > 0 and n != ESCAPE_BYTE and n <= 0xFF.
+ * If we encounter a run where n == ESCAPE_BYTE, we represent this as:
+ *   b ESCAPE_BYTE n-1 b
+ * The ESCAPE_BYTE value is chosen so as not to collide with commonly
+ * seen values.
+ */
+int32_t
+byteArrayToRLEString(const uint8_t* src,int32_t srcLen, uint16_t* buffer,int32_t bufLen, UErrorCode* status);
+
+
+/**
+ * Construct a string representing a char array.  Use run-length encoding.
+ * A character represents itself, unless it is the ESCAPE character.  Then
+ * the following notations are possible:
+ *   ESCAPE ESCAPE   ESCAPE literal
+ *   ESCAPE n c      n instances of character c
+ * Since an encoded run occupies 3 characters, we only encode runs of 4 or
+ * more characters.  Thus we have n > 0 and n != ESCAPE and n <= 0xFFFF.
+ * If we encounter a run where n == ESCAPE, we represent this as:
+ *   c ESCAPE n-1 c
+ * The ESCAPE value is chosen so as not to collide with commonly
+ * seen values.
+ */
+int32_t
+usArrayToRLEString(const uint16_t* src,int32_t srcLen,uint16_t* buffer, int32_t bufLen,UErrorCode* status);
+
+/**
+ * Construct an array of bytes from a run-length encoded string.
+ */
+int32_t
+rleStringToByteArray(uint16_t* src, int32_t srcLen, uint8_t* target, int32_t tgtLen, UErrorCode* status); 
+/**
+ * Construct an array of shorts from a run-length encoded string.
+ */
+int32_t
+rleStringToUCharArray(uint16_t* src, int32_t srcLen, uint16_t* target, int32_t tgtLen, UErrorCode* status);
+
+U_CDECL_END
+
+#endif