jpayne@69: // © 2016 and later: Unicode, Inc. and others.
jpayne@69: // License & terms of use: http://www.unicode.org/copyright.html
jpayne@69: /*
jpayne@69: **********************************************************************
jpayne@69: * Copyright (C) 2000-2004, International Business Machines
jpayne@69: * Corporation and others. All Rights Reserved.
jpayne@69: **********************************************************************
jpayne@69: * ucnv_cb.h:
jpayne@69: * External APIs for the ICU's codeset conversion library
jpayne@69: * Helena Shih
jpayne@69: *
jpayne@69: * Modification History:
jpayne@69: *
jpayne@69: * Date Name Description
jpayne@69: */
jpayne@69:
jpayne@69: /**
jpayne@69: * \file
jpayne@69: * \brief C UConverter functions to aid the writers of callbacks
jpayne@69: *
jpayne@69: * Callback API for UConverter
jpayne@69: *
jpayne@69: * These functions are provided here for the convenience of the callback
jpayne@69: * writer. If you are just looking for callback functions to use, please
jpayne@69: * see ucnv_err.h. DO NOT call these functions directly when you are
jpayne@69: * working with converters, unless your code has been called as a callback
jpayne@69: * via ucnv_setFromUCallback or ucnv_setToUCallback !!
jpayne@69: *
jpayne@69: * A note about error codes and overflow. Unlike other ICU functions,
jpayne@69: * these functions do not expect the error status to be U_ZERO_ERROR.
jpayne@69: * Callbacks must be much more careful about their error codes.
jpayne@69: * The error codes used here are in/out parameters, which should be passed
jpayne@69: * back in the callback's error parameter.
jpayne@69: *
jpayne@69: * For example, if you call ucnv_cbfromUWriteBytes to write data out
jpayne@69: * to the output codepage, it may return U_BUFFER_OVERFLOW_ERROR if
jpayne@69: * the data did not fit in the target. But this isn't a failing error,
jpayne@69: * in fact, ucnv_cbfromUWriteBytes may be called AGAIN with the error
jpayne@69: * status still U_BUFFER_OVERFLOW_ERROR to attempt to write further bytes,
jpayne@69: * which will also go into the internal overflow buffers.
jpayne@69: *
jpayne@69: * Concerning offsets, the 'offset' parameters here are relative to the start
jpayne@69: * of SOURCE. For example, Suppose the string "ABCD" was being converted
jpayne@69: * from Unicode into a codepage which doesn't have a mapping for 'B'.
jpayne@69: * 'A' will be written out correctly, but
jpayne@69: * The FromU Callback will be called on an unassigned character for 'B'.
jpayne@69: * At this point, this is the state of the world:
jpayne@69: * Target: A [..] [points after A]
jpayne@69: * Source: A B [C] D [points to C - B has been consumed]
jpayne@69: * 0 1 2 3
jpayne@69: * codePoint = "B" [the unassigned codepoint]
jpayne@69: *
jpayne@69: * Now, suppose a callback wants to write the substitution character '?' to
jpayne@69: * the target. It calls ucnv_cbFromUWriteBytes() to write the ?.
jpayne@69: * It should pass ZERO as the offset, because the offset as far as the
jpayne@69: * callback is concerned is relative to the SOURCE pointer [which points
jpayne@69: * before 'C'.] If the callback goes into the args and consumes 'C' also,
jpayne@69: * it would call FromUWriteBytes with an offset of 1 (and advance the source
jpayne@69: * pointer).
jpayne@69: *
jpayne@69: */
jpayne@69:
jpayne@69: #ifndef UCNV_CB_H
jpayne@69: #define UCNV_CB_H
jpayne@69:
jpayne@69: #include "unicode/utypes.h"
jpayne@69:
jpayne@69: #if !UCONFIG_NO_CONVERSION
jpayne@69:
jpayne@69: #include "unicode/ucnv.h"
jpayne@69: #include "unicode/ucnv_err.h"
jpayne@69:
jpayne@69: /**
jpayne@69: * ONLY used by FromU callback functions.
jpayne@69: * Writes out the specified byte output bytes to the target byte buffer or to converter internal buffers.
jpayne@69: *
jpayne@69: * @param args callback fromUnicode arguments
jpayne@69: * @param source source bytes to write
jpayne@69: * @param length length of bytes to write
jpayne@69: * @param offsetIndex the relative offset index from callback.
jpayne@69: * @param err error status. If U_BUFFER_OVERFLOW is returned, then U_BUFFER_OVERFLOW must
jpayne@69: * be returned to the user, because it means that not all data could be written into the target buffer, and some is
jpayne@69: * in the converter error buffer.
jpayne@69: * @see ucnv_cbFromUWriteSub
jpayne@69: * @stable ICU 2.0
jpayne@69: */
jpayne@69: U_STABLE void U_EXPORT2
jpayne@69: ucnv_cbFromUWriteBytes (UConverterFromUnicodeArgs *args,
jpayne@69: const char* source,
jpayne@69: int32_t length,
jpayne@69: int32_t offsetIndex,
jpayne@69: UErrorCode * err);
jpayne@69:
jpayne@69: /**
jpayne@69: * ONLY used by FromU callback functions.
jpayne@69: * This function will write out the correct substitution character sequence
jpayne@69: * to the target.
jpayne@69: *
jpayne@69: * @param args callback fromUnicode arguments
jpayne@69: * @param offsetIndex the relative offset index from the current source pointer to be used
jpayne@69: * @param err error status. If U_BUFFER_OVERFLOW is returned, then U_BUFFER_OVERFLOW must
jpayne@69: * be returned to the user, because it means that not all data could be written into the target buffer, and some is
jpayne@69: * in the converter error buffer.
jpayne@69: * @see ucnv_cbFromUWriteBytes
jpayne@69: * @stable ICU 2.0
jpayne@69: */
jpayne@69: U_STABLE void U_EXPORT2
jpayne@69: ucnv_cbFromUWriteSub (UConverterFromUnicodeArgs *args,
jpayne@69: int32_t offsetIndex,
jpayne@69: UErrorCode * err);
jpayne@69:
jpayne@69: /**
jpayne@69: * ONLY used by fromU callback functions.
jpayne@69: * This function will write out the error character(s) to the target UChar buffer.
jpayne@69: *
jpayne@69: * @param args callback fromUnicode arguments
jpayne@69: * @param source pointer to pointer to first UChar to write [on exit: 1 after last UChar processed]
jpayne@69: * @param sourceLimit pointer after last UChar to write
jpayne@69: * @param offsetIndex the relative offset index from callback which will be set
jpayne@69: * @param err error status U_BUFFER_OVERFLOW
jpayne@69: * @see ucnv_cbToUWriteSub
jpayne@69: * @stable ICU 2.0
jpayne@69: */
jpayne@69: U_STABLE void U_EXPORT2 ucnv_cbFromUWriteUChars(UConverterFromUnicodeArgs *args,
jpayne@69: const UChar** source,
jpayne@69: const UChar* sourceLimit,
jpayne@69: int32_t offsetIndex,
jpayne@69: UErrorCode * err);
jpayne@69:
jpayne@69: /**
jpayne@69: * ONLY used by ToU callback functions.
jpayne@69: * This function will write out the specified characters to the target
jpayne@69: * UChar buffer.
jpayne@69: *
jpayne@69: * @param args callback toUnicode arguments
jpayne@69: * @param source source string to write
jpayne@69: * @param length the length of source string
jpayne@69: * @param offsetIndex the relative offset index which will be written.
jpayne@69: * @param err error status U_BUFFER_OVERFLOW
jpayne@69: * @see ucnv_cbToUWriteSub
jpayne@69: * @stable ICU 2.0
jpayne@69: */
jpayne@69: U_STABLE void U_EXPORT2 ucnv_cbToUWriteUChars (UConverterToUnicodeArgs *args,
jpayne@69: const UChar* source,
jpayne@69: int32_t length,
jpayne@69: int32_t offsetIndex,
jpayne@69: UErrorCode * err);
jpayne@69:
jpayne@69: /**
jpayne@69: * ONLY used by ToU callback functions.
jpayne@69: * This function will write out the Unicode substitution character (U+FFFD).
jpayne@69: *
jpayne@69: * @param args callback fromUnicode arguments
jpayne@69: * @param offsetIndex the relative offset index from callback.
jpayne@69: * @param err error status U_BUFFER_OVERFLOW
jpayne@69: * @see ucnv_cbToUWriteUChars
jpayne@69: * @stable ICU 2.0
jpayne@69: */
jpayne@69: U_STABLE void U_EXPORT2 ucnv_cbToUWriteSub (UConverterToUnicodeArgs *args,
jpayne@69: int32_t offsetIndex,
jpayne@69: UErrorCode * err);
jpayne@69: #endif
jpayne@69:
jpayne@69: #endif