gecko-dev/xpcom/io/nsIUnicharInputStream.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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 * The Original Code is mozilla.org code.
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#ifndef nsIUnicharInputStream_h___
#define nsIUnicharInputStream_h___

#include "nsIInputStream.h"
#include "nscore.h"

class nsString;
class nsIUnicharInputStream;

typedef NS_CALLBACK(nsWriteUnicharSegmentFun)(nsIUnicharInputStream *aInStream,
                                              void *aClosure,
                                              const PRUnichar *aFromSegment,
                                              PRUint32 aToOffset,
                                              PRUint32 aCount,
                                              PRUint32 *aWriteCount);
/* c4bcf6ee-3a79-4d77-8d48-f17be3199b3b */
#define NS_IUNICHAR_INPUT_STREAM_IID \
{ 0xc4bcf6ee, 0x3a79, 0x4d77,        \
  {0x8d, 0x48, 0xf1, 0x7b, 0xe3, 0x19, 0x9b, 0x3b} }

/** Abstract unicode character input stream
 *  @see nsIInputStream
 */
class NS_NO_VTABLE nsIUnicharInputStream : public nsISupports {
public:
	NS_DEFINE_STATIC_IID_ACCESSOR(NS_IUNICHAR_INPUT_STREAM_IID)

  NS_IMETHOD Read(PRUnichar* aBuf,
                  PRUint32 aCount,
                  PRUint32 *aReadCount) = 0;
  NS_IMETHOD Close() = 0;
  NS_IMETHOD ReadSegments(nsWriteUnicharSegmentFun aWriter,
                          void* aClosure,
                          PRUint32 aCount,
                          PRUint32 *aReadCount) = 0;
};

/**
 * Create a nsIUnicharInputStream that wraps up a string. Data is fed
 * from the string out until the done. When this object is destroyed
 * it destroyes the string (so make a copy if you don't want it doing
 * that)
 */
extern NS_COM nsresult
  NS_NewStringUnicharInputStream(nsIUnicharInputStream** aInstancePtrResult,
                                 nsString* aString);

/** Create a new nsUnicharInputStream that provides a converter for the
 * byte input stream aStreamToWrap. If no converter can be found then
 * nsnull is returned and the error code is set to
 * NS_INPUTSTREAM_NO_CONVERTER.
 */
extern NS_COM nsresult
  NS_NewUTF8ConverterStream(nsIUnicharInputStream** aInstancePtrResult,
                            nsIInputStream* aStreamToWrap,
                            PRInt32 aBufferSize = 0);

#endif /* nsUnicharInputStream_h___ */