165 lines
6.6 KiB
C++
165 lines
6.6 KiB
C++
|
// © 2016 and later: Unicode, Inc. and others.
|
||
|
|
// License & terms of use: http://www.unicode.org/copyright.html
|
||
|
|
/*
|
||
|
|
**********************************************************************
|
||
|
|
* Copyright (C) 2000-2004, International Business Machines
|
||
|
|
* Corporation and others. All Rights Reserved.
|
||
|
|
**********************************************************************
|
||
|
|
* ucnv_cb.h:
|
||
|
|
* External APIs for the ICU's codeset conversion library
|
||
|
|
* Helena Shih
|
||
|
|
*
|
||
|
|
* Modification History:
|
||
|
|
*
|
||
|
|
* Date Name Description
|
||
|
|
*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* \file
|
||
|
|
* \brief C UConverter functions to aid the writers of callbacks
|
||
|
|
*
|
||
|
|
* <h2> Callback API for UConverter </h2>
|
||
|
|
*
|
||
|
|
* These functions are provided here for the convenience of the callback
|
||
|
|
* writer. If you are just looking for callback functions to use, please
|
||
|
|
* see ucnv_err.h. DO NOT call these functions directly when you are
|
||
|
|
* working with converters, unless your code has been called as a callback
|
||
|
|
* via ucnv_setFromUCallback or ucnv_setToUCallback !!
|
||
|
|
*
|
||
|
|
* A note about error codes and overflow. Unlike other ICU functions,
|
||
|
|
* these functions do not expect the error status to be U_ZERO_ERROR.
|
||
|
|
* Callbacks must be much more careful about their error codes.
|
||
|
|
* The error codes used here are in/out parameters, which should be passed
|
||
|
|
* back in the callback's error parameter.
|
||
|
|
*
|
||
|
|
* For example, if you call ucnv_cbfromUWriteBytes to write data out
|
||
|
|
* to the output codepage, it may return U_BUFFER_OVERFLOW_ERROR if
|
||
|
|
* the data did not fit in the target. But this isn't a failing error,
|
||
|
|
* in fact, ucnv_cbfromUWriteBytes may be called AGAIN with the error
|
||
|
|
* status still U_BUFFER_OVERFLOW_ERROR to attempt to write further bytes,
|
||
|
|
* which will also go into the internal overflow buffers.
|
||
|
|
*
|
||
|
|
* Concerning offsets, the 'offset' parameters here are relative to the start
|
||
|
|
* of SOURCE. For example, Suppose the string "ABCD" was being converted
|
||
|
|
* from Unicode into a codepage which doesn't have a mapping for 'B'.
|
||
|
|
* 'A' will be written out correctly, but
|
||
|
|
* The FromU Callback will be called on an unassigned character for 'B'.
|
||
|
|
* At this point, this is the state of the world:
|
||
|
|
* Target: A [..] [points after A]
|
||
|
|
* Source: A B [C] D [points to C - B has been consumed]
|
||
|
|
* 0 1 2 3
|
||
|
|
* codePoint = "B" [the unassigned codepoint]
|
||
|
|
*
|
||
|
|
* Now, suppose a callback wants to write the substitution character '?' to
|
||
|
|
* the target. It calls ucnv_cbFromUWriteBytes() to write the ?.
|
||
|
|
* It should pass ZERO as the offset, because the offset as far as the
|
||
|
|
* callback is concerned is relative to the SOURCE pointer [which points
|
||
|
|
* before 'C'.] If the callback goes into the args and consumes 'C' also,
|
||
|
|
* it would call FromUWriteBytes with an offset of 1 (and advance the source
|
||
|
|
* pointer).
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef UCNV_CB_H
|
||
|
|
#define UCNV_CB_H
|
||
|
|
|
||
|
|
#include "unicode/utypes.h"
|
||
|
|
|
||
|
|
#if !UCONFIG_NO_CONVERSION
|
||
|
|
|
||
|
|
#include "unicode/ucnv.h"
|
||
|
|
#include "unicode/ucnv_err.h"
|
||
|
|
|
||
|
|
/**
|
||
|
|
* ONLY used by FromU callback functions.
|
||
|
|
* Writes out the specified byte output bytes to the target byte buffer or to converter internal buffers.
|
||
|
|
*
|
||
|
|
* @param args callback fromUnicode arguments
|
||
|
|
* @param source source bytes to write
|
||
|
|
* @param length length of bytes to write
|
||
|
|
* @param offsetIndex the relative offset index from callback.
|
||
|
|
* @param err error status. If <TT>U_BUFFER_OVERFLOW</TT> is returned, then U_BUFFER_OVERFLOW <STRONG>must</STRONG>
|
||
|
|
* be returned to the user, because it means that not all data could be written into the target buffer, and some is
|
||
|
|
* in the converter error buffer.
|
||
|
|
* @see ucnv_cbFromUWriteSub
|
||
|
|
* @stable ICU 2.0
|
||
|
|
*/
|
||
|
|
U_CAPI void U_EXPORT2
|
||
|
|
ucnv_cbFromUWriteBytes (UConverterFromUnicodeArgs *args,
|
||
|
|
const char* source,
|
||
|
|
int32_t length,
|
||
|
|
int32_t offsetIndex,
|
||
|
|
UErrorCode * err);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* ONLY used by FromU callback functions.
|
||
|
|
* This function will write out the correct substitution character sequence
|
||
|
|
* to the target.
|
||
|
|
*
|
||
|
|
* @param args callback fromUnicode arguments
|
||
|
|
* @param offsetIndex the relative offset index from the current source pointer to be used
|
||
|
|
* @param err error status. If <TT>U_BUFFER_OVERFLOW</TT> is returned, then U_BUFFER_OVERFLOW <STRONG>must</STRONG>
|
||
|
|
* be returned to the user, because it means that not all data could be written into the target buffer, and some is
|
||
|
|
* in the converter error buffer.
|
||
|
|
* @see ucnv_cbFromUWriteBytes
|
||
|
|
* @stable ICU 2.0
|
||
|
|
*/
|
||
|
|
U_CAPI void U_EXPORT2
|
||
|
|
ucnv_cbFromUWriteSub (UConverterFromUnicodeArgs *args,
|
||
|
|
int32_t offsetIndex,
|
||
|
|
UErrorCode * err);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* ONLY used by fromU callback functions.
|
||
|
|
* This function will write out the error character(s) to the target UChar buffer.
|
||
|
|
*
|
||
|
|
* @param args callback fromUnicode arguments
|
||
|
|
* @param source pointer to pointer to first UChar to write [on exit: 1 after last UChar processed]
|
||
|
|
* @param sourceLimit pointer after last UChar to write
|
||
|
|
* @param offsetIndex the relative offset index from callback which will be set
|
||
|
|
* @param err error status <TT>U_BUFFER_OVERFLOW</TT>
|
||
|
|
* @see ucnv_cbToUWriteSub
|
||
|
|
* @stable ICU 2.0
|
||
|
|
*/
|
||
|
|
U_CAPI void U_EXPORT2 ucnv_cbFromUWriteUChars(UConverterFromUnicodeArgs *args,
|
||
|
|
const UChar** source,
|
||
|
|
const UChar* sourceLimit,
|
||
|
|
int32_t offsetIndex,
|
||
|
|
UErrorCode * err);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* ONLY used by ToU callback functions.
|
||
|
|
* This function will write out the specified characters to the target
|
||
|
|
* UChar buffer.
|
||
|
|
*
|
||
|
|
* @param args callback toUnicode arguments
|
||
|
|
* @param source source string to write
|
||
|
|
* @param length the length of source string
|
||
|
|
* @param offsetIndex the relative offset index which will be written.
|
||
|
|
* @param err error status <TT>U_BUFFER_OVERFLOW</TT>
|
||
|
|
* @see ucnv_cbToUWriteSub
|
||
|
|
* @stable ICU 2.0
|
||
|
|
*/
|
||
|
|
U_CAPI void U_EXPORT2 ucnv_cbToUWriteUChars (UConverterToUnicodeArgs *args,
|
||
|
|
const UChar* source,
|
||
|
|
int32_t length,
|
||
|
|
int32_t offsetIndex,
|
||
|
|
UErrorCode * err);
|
||
|
|
|
||
|
|
/**
|
||
|
|
* ONLY used by ToU callback functions.
|
||
|
|
* This function will write out the Unicode substitution character (U+FFFD).
|
||
|
|
*
|
||
|
|
* @param args callback fromUnicode arguments
|
||
|
|
* @param offsetIndex the relative offset index from callback.
|
||
|
|
* @param err error status <TT>U_BUFFER_OVERFLOW</TT>
|
||
|
|
* @see ucnv_cbToUWriteUChars
|
||
|
|
* @stable ICU 2.0
|
||
|
|
*/
|
||
|
|
U_CAPI void U_EXPORT2 ucnv_cbToUWriteSub (UConverterToUnicodeArgs *args,
|
||
|
|
int32_t offsetIndex,
|
||
|
|
UErrorCode * err);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#endif
|