gecko/intl/uconv/nsIUnicodeEncoder.h

160 lines
6.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsIUnicodeEncoder_h___
#define nsIUnicodeEncoder_h___
#include "nscore.h"
#include "nsError.h"
#include "nsISupports.h"
// Interface ID for our Unicode Encoder interface
// {2B2CA3D0-A4C9-11d2-8AA1-00600811A836}
#define NS_IUNICODEENCODER_IID \
{ 0x2b2ca3d0, 0xa4c9, 0x11d2, \
{ 0x8a, 0xa1, 0x0, 0x60, 0x8, 0x11, 0xa8, 0x36 }}
// Interface ID for our Unicode Character Encoder interface
// {299BCCD0-C6DF-11d2-8AA8-00600811A836}
#define NS_IUNICHARENCODER_IID \
{ 0x299bccd0, 0xc6df, 0x11d2, \
{0x8a, 0xa8, 0x0, 0x60, 0x8, 0x11, 0xa8, 0x36 }}
#define NS_UNICODEENCODER_CONTRACTID_BASE "@mozilla.org/intl/unicode/encoder;1?charset="
/**
* Interface which converts a single character from Unicode into a given
* charset.
*
* @created 17/Feb/1999
* @author Catalin Rotaru [CATA]
*/
class nsIUnicharEncoder : public nsISupports
{
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_IUNICHARENCODER_IID)
/**
* Converts a character from Unicode to a Charset.
*/
NS_IMETHOD Convert(char16_t aChar, char * aDest, int32_t * aDestLength) = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsIUnicharEncoder, NS_IUNICHARENCODER_IID)
/**
* Interface for a Converter from Unicode into a Charset.
*
* @created 23/Nov/1998
* @author Catalin Rotaru [CATA]
*/
class nsIUnicodeEncoder : public nsISupports
{
public:
NS_DECLARE_STATIC_IID_ACCESSOR(NS_IUNICODEENCODER_IID)
enum {
kOnError_Signal, // on an error, stop and signal
kOnError_CallBack, // on an error, call the error handler
kOnError_Replace // on an error, replace with a different character
};
/**
* Converts the data from Unicode to a Charset.
*
* About the byte ordering:
* - The input stream is Unicode, having the byte order which is internal
* for the machine on which the converter is running on.
* - For output, if the converter cares (that depends of the charset, for
* example a singlebyte will ignore the byte ordering) it should assume
* network order. If necessary and requested, we can add a method
* SetOutputByteOrder() so that the reverse order can be used, too. That
* method would have as default the assumed network order.
*
* For the last converted char, even if there is not enough output
* space, a partial output must be done until all available space will be
* used. The rest of the output should be buffered until more space becomes
* available. But this is not also true about the error handling method!!!
* So be very, very careful...
*
* @param aSrc [IN] the source data buffer
* @param aSrcLength [IN/OUT] the length of source data buffer; after
* conversion will contain the number of Unicode
* characters read
* @param aDest [OUT] the destination data buffer
* @param aDestLength [IN/OUT] the length of the destination data buffer;
* after conversion will contain the number of bytes
* written
* @return NS_OK_UENC_MOREOUTPUT if only a partial conversion
* was done; more output space is needed to continue
* NS_OK_UENC_MOREINPUT if only a partial conversion
* was done; more input is needed to continue. This can
* occur when the last UTF-16 code point in the input is
* the first of a surrogate pair.
* NS_ERROR_UENC_NOMAPPING if character without mapping
* was encountered and the behavior was set to "signal".
* In the case of an unmappable BMP character, aDestLength
* must indicate that the unmappable character was
* consumed by the encoder (unlike in the decode API!).
* In the case of an unmappable astral character,
* aDestLength must indicate that the high surrogate was
* consumed by the encoder but the low surrogate was not.
* NS_OK otherwise.
*/
NS_IMETHOD Convert(const char16_t * aSrc, int32_t * aSrcLength,
char * aDest, int32_t * aDestLength) = 0;
/**
* Finishes the conversion. The converter has the possibility to write some
* extra data and flush its final state.
*
* @param aDest [OUT] the destination data buffer
* @param aDestLength [IN/OUT] the length of destination data buffer; after
* conversion it will contain the number of bytes written
* @return NS_OK_UENC_MOREOUTPUT if only a partial conversion
* was done; more output space is needed to continue.
* NS_ERROR_UENC_NOMAPPING if input ended with an unpaired
* high surrogate, the behavior was "signal" and the
* encoding can't represent U+FFFD.
* NS_OK otherwise.
*/
NS_IMETHOD Finish(char * aDest, int32_t * aDestLength) = 0;
/**
* Returns a quick estimation of the size of the buffer needed to hold the
* converted data. Remember: this estimation is >= with the actual size of
* the buffer needed. It will be computed for the "worst case"
*
* @param aSrc [IN] the source data buffer
* @param aSrcLength [IN] the length of source data buffer
* @param aDestLength [OUT] the needed size of the destination buffer
* @return NS_OK_UENC_EXACTLENGTH if an exact length was computed
* NS_ERROR_OUT_OF_MEMORY if OOM
* NS_OK if all we have is an approximation
*/
MOZ_WARN_UNUSED_RESULT NS_IMETHOD GetMaxLength(const char16_t* aSrc,
int32_t aSrcLength,
int32_t* aDestLength) = 0;
/**
* Resets the charset converter so it may be recycled for a completely
* different and urelated buffer of data.
*/
NS_IMETHOD Reset() = 0;
/**
* Specify what to do when a character cannot be mapped into the dest charset
*
* @param aOrder [IN] the behavior; taken from the enum
*/
NS_IMETHOD SetOutputErrorBehavior(int32_t aBehavior,
nsIUnicharEncoder * aEncoder, char16_t aChar) = 0;
};
NS_DEFINE_STATIC_IID_ACCESSOR(nsIUnicodeEncoder, NS_IUNICODEENCODER_IID)
#endif /* nsIUnicodeEncoder_h___ */