tor-browser

The Tor Browser
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rle.h (2646B)

      1 // © 2016 and later: Unicode, Inc. and others.
      2 // License & terms of use: http://www.unicode.org/copyright.html
      3 /*
      4 *******************************************************************************
      5 *
      6 *   Copyright (C) 2000, International Business Machines
      7 *   Corporation and others.  All Rights Reserved.
      8 *
      9 *******************************************************************************
     10 *
     11 * File writejava.c
     12 *
     13 * Modification History:
     14 *
     15 *   Date        Name        Description
     16 *   01/11/02    Ram        Creation.
     17 *******************************************************************************
     18 */
     19 
     20 #ifndef RLE_H
     21 #define RLE_H 1
     22 
     23 #include "unicode/utypes.h"
     24 #include "unicode/ustring.h"
     25 
     26 U_CDECL_BEGIN
     27 /**
     28 * Construct a string representing a byte array.  Use run-length encoding.
     29 * Two bytes are packed into a single char, with a single extra zero byte at
     30 * the end if needed.  A byte represents itself, unless it is the
     31 * ESCAPE_BYTE.  Then the following notations are possible:
     32 *   ESCAPE_BYTE ESCAPE_BYTE   ESCAPE_BYTE literal
     33 *   ESCAPE_BYTE n b           n instances of byte b
     34 * Since an encoded run occupies 3 bytes, we only encode runs of 4 or
     35 * more bytes.  Thus we have n > 0 and n != ESCAPE_BYTE and n <= 0xFF.
     36 * If we encounter a run where n == ESCAPE_BYTE, we represent this as:
     37 *   b ESCAPE_BYTE n-1 b
     38 * The ESCAPE_BYTE value is chosen so as not to collide with commonly
     39 * seen values.
     40 */
     41 int32_t
     42 byteArrayToRLEString(const uint8_t* src,int32_t srcLen, uint16_t* buffer,int32_t bufLen, UErrorCode* status);
     43 
     44 
     45 /**
     46 * Construct a string representing a char array.  Use run-length encoding.
     47 * A character represents itself, unless it is the ESCAPE character.  Then
     48 * the following notations are possible:
     49 *   ESCAPE ESCAPE   ESCAPE literal
     50 *   ESCAPE n c      n instances of character c
     51 * Since an encoded run occupies 3 characters, we only encode runs of 4 or
     52 * more characters.  Thus we have n > 0 and n != ESCAPE and n <= 0xFFFF.
     53 * If we encounter a run where n == ESCAPE, we represent this as:
     54 *   c ESCAPE n-1 c
     55 * The ESCAPE value is chosen so as not to collide with commonly
     56 * seen values.
     57 */
     58 int32_t
     59 usArrayToRLEString(const uint16_t* src,int32_t srcLen,uint16_t* buffer, int32_t bufLen,UErrorCode* status);
     60 
     61 /**
     62 * Construct an array of bytes from a run-length encoded string.
     63 */
     64 int32_t
     65 rleStringToByteArray(uint16_t* src, int32_t srcLen, uint8_t* target, int32_t tgtLen, UErrorCode* status); 
     66 /**
     67 * Construct an array of shorts from a run-length encoded string.
     68 */
     69 int32_t
     70 rleStringToUCharArray(uint16_t* src, int32_t srcLen, uint16_t* target, int32_t tgtLen, UErrorCode* status);
     71 
     72 U_CDECL_END
     73 
     74 #endif