pjs/xpcom/io/nsBinaryStream.cpp

378 строки
9.3 KiB
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Исходник Обычный вид История

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* The contents of this file are subject to the Netscape Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/NPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is Mozilla Communicator client code, released
* March 31, 1998.
*
* The Initial Developer of the Original Code is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998-1999 Netscape Communications Corporation. All
* Rights Reserved.
*
*/
/**
* This file contains implementations of the nsIBinaryInputStream and
* nsIBinaryOutputStream interfaces. Together, these interfaces allows reading
* and writing of primitive data types (integers, floating-point values,
* booleans, etc.) to a stream in a binary, untagged, fixed-endianness format.
* This might be used, for example, to implement network protocols or to
* produce architecture-neutral binary disk files, i.e. ones that can be read
* and written by both big-endian and little-endian platforms. Output is
* written in big-endian order (high-order byte first), as this is traditional
* network order.
*
* @See nsIBinaryInputStream
* @See nsIBinaryOutputStream
*/
#include "nsBinaryStream.h"
#include "nsIAllocator.h"
#include <string.h>
// Swap macros, used to convert to/from canonical (big-endian) format
#ifdef IS_LITTLE_ENDIAN
# define SWAP16(x) ((((x) & 0xff) << 8) | (((x) >> 8) & 0xff))
# define SWAP32(x) ((SWAP16((x) & 0xffff) << 16) | (SWAP16((x) >> 16)))
#else
# ifndef IS_BIG_ENDIAN
# error "Unknown endianness"
# endif
# define SWAP16(x) (x)
# define SWAP32(x) (x)
#endif
nsBinaryOutputStream::nsBinaryOutputStream(nsIOutputStream* aStream): mOutputStream(aStream)
{
NS_INIT_REFCNT();
}
NS_IMPL_ISUPPORTS(nsBinaryOutputStream, NS_GET_IID(nsIBinaryOutputStream))
NS_IMETHODIMP
nsBinaryOutputStream::Flush() { return mOutputStream->Flush(); }
NS_IMETHODIMP
nsBinaryOutputStream::Close() { return mOutputStream->Close(); }
NS_IMETHODIMP
nsBinaryOutputStream::Write(const char *aBuf, PRUint32 aCount, PRUint32 *aActualBytes)
{
return mOutputStream->Write(aBuf, aCount, aActualBytes);
}
nsresult
nsBinaryOutputStream::WriteFully(const char *aBuf, PRUint32 aCount)
{
nsresult rv;
PRUint32 actualBytesWritten;
rv = mOutputStream->Write(aBuf, aCount, &actualBytesWritten);
if (NS_FAILED(rv)) return rv;
if (actualBytesWritten != aCount)
return NS_ERROR_FAILURE;
return NS_OK;
}
NS_IMETHODIMP
nsBinaryOutputStream::SetOutputStream(nsIOutputStream *aOutputStream)
{
NS_ENSURE_ARG_POINTER(aOutputStream);
mOutputStream = aOutputStream;
return NS_OK;
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteBoolean(PRBool aBoolean)
{
return Write8(aBoolean);
}
NS_IMETHODIMP
nsBinaryOutputStream::Write8(PRUint8 aByte)
{
return WriteFully((const char*)&aByte, sizeof aByte);
}
NS_IMETHODIMP
nsBinaryOutputStream::Write16(PRUint16 a16)
{
a16 = SWAP16(a16);
return WriteFully((const char*)&a16, sizeof a16);
}
NS_IMETHODIMP
nsBinaryOutputStream::Write32(PRUint32 a32)
{
a32 = SWAP32(a32);
return WriteFully((const char*)&a32, sizeof a32);
}
NS_IMETHODIMP
nsBinaryOutputStream::Write64(PRUint64 a64)
{
nsresult rv;
PRUint32* raw32 = (PRUint32*)&a64;
#ifdef IS_BIG_ENDIAN
rv = Write32(raw32[0]);
if (NS_FAILED(rv)) return rv;
return Write32(raw32[1]);
#else
rv = Write32(raw32[1]);
if (NS_FAILED(rv)) return rv;
return Write32(raw32[0]);
#endif
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteFloat(float aFloat)
{
NS_ASSERTION(sizeof(float) == sizeof (PRUint32),
"False assumption about sizeof(float)");
return Write32(*NS_REINTERPRET_CAST(PRUint32*, &aFloat));
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteDouble(double aDouble)
{
NS_ASSERTION(sizeof(double) == sizeof(PRUint64),
"False assumption about sizeof(double)");
return Write64(*NS_REINTERPRET_CAST(PRUint64*,&aDouble));
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteStringZ(const char *aString)
{
return WriteFully(aString, strlen(aString) + 1);
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteWStringZ(const PRUnichar* aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteUtf8Z(const PRUnichar* aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteBytes(const char *aString, PRUint32 aLength)
{
nsresult rv;
PRUint32 bytesWritten;
rv = Write(aString, aLength, &bytesWritten);
if (bytesWritten != aLength)
return NS_ERROR_FAILURE;
return rv;
}
NS_IMETHODIMP
nsBinaryOutputStream::WriteString(nsString* aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
nsBinaryInputStream::nsBinaryInputStream(nsIInputStream* aStream): mInputStream(aStream) { NS_INIT_REFCNT(); }
NS_IMPL_ISUPPORTS(nsBinaryInputStream, NS_GET_IID(nsIBinaryInputStream))
NS_IMETHODIMP
nsBinaryInputStream::Available(PRUint32* aResult) { return mInputStream->Available(aResult); }
NS_IMETHODIMP
nsBinaryInputStream::Read(char* aBuffer, PRUint32 aCount, PRUint32 *aNumRead)
{
return mInputStream->Read(aBuffer, aCount, aNumRead);
}
NS_IMETHODIMP
nsBinaryInputStream::Close() { return mInputStream->Close(); }
NS_IMETHODIMP
nsBinaryInputStream::SetInputStream(nsIInputStream *aInputStream)
{
NS_ENSURE_ARG_POINTER(aInputStream);
mInputStream = aInputStream;
return NS_OK;
}
NS_IMETHODIMP
nsBinaryInputStream::ReadBoolean(PRBool* aBoolean)
{
PRUint8 byteResult;
nsresult rv = Read8(&byteResult);
*aBoolean = byteResult;
return rv;
}
NS_IMETHODIMP
nsBinaryInputStream::Read8(PRUint8* aByte)
{
nsresult rv;
PRUint32 bytesRead;
rv = Read((char*)aByte, sizeof(*aByte), &bytesRead);
if (NS_FAILED(rv)) return rv;
if (bytesRead != sizeof (*aByte))
return NS_ERROR_FAILURE;
return rv;
}
NS_IMETHODIMP
nsBinaryInputStream::Read16(PRUint16* a16)
{
nsresult rv;
PRUint32 bytesRead;
rv = Read((char*)a16, sizeof *a16, &bytesRead);
if (NS_FAILED(rv)) return rv;
if (bytesRead != sizeof *a16)
return NS_ERROR_FAILURE;
*a16 = SWAP16(*a16);
return rv;
}
NS_IMETHODIMP
nsBinaryInputStream::Read32(PRUint32* a32)
{
nsresult rv;
PRUint32 bytesRead;
rv = Read((char*)a32, sizeof *a32, &bytesRead);
if (NS_FAILED(rv)) return rv;
if (bytesRead != sizeof *a32)
return NS_ERROR_FAILURE;
*a32 = SWAP32(*a32);
return rv;
}
NS_IMETHODIMP
nsBinaryInputStream::Read64(PRUint64* a64)
{
nsresult rv;
PRUint32* raw32 = (PRUint32*)a64;
#ifdef IS_BIG_ENDIAN
rv = Read32(&raw32[0]);
if (NS_FAILED(rv)) return rv;
return Read32(&raw32[1]);
#else
rv = Read32(&raw32[1]);
if (NS_FAILED(rv)) return rv;
return Read32(&raw32[0]);
#endif
}
NS_IMETHODIMP
nsBinaryInputStream::ReadFloat(float* aFloat)
{
NS_ASSERTION(sizeof(float) == sizeof (PRUint32),
"False assumption about sizeof(float)");
return Read32(NS_REINTERPRET_CAST(PRUint32*, aFloat));
}
NS_IMETHODIMP
nsBinaryInputStream::ReadDouble(double* aDouble)
{
NS_ASSERTION(sizeof(double) == sizeof(PRUint64),
"False assumption about sizeof(double)");
return Read64(NS_REINTERPRET_CAST(PRUint64*, aDouble));
}
NS_IMETHODIMP
nsBinaryInputStream::ReadStringZ(char* *aString)
{
nsresult rv;
nsAutoString result;
char c;
for ( ; ; )
{
PRUint32 actualBytesRead;
rv = Read(&c, 1, &actualBytesRead);
if (NS_FAILED(rv) || actualBytesRead != 1)
return NS_ERROR_FAILURE;
if (c)
result += c;
else
break;
}
*aString = result.ToNewCString();
return NS_OK;
}
NS_IMETHODIMP
nsBinaryInputStream::ReadWStringZ(PRUnichar* *aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsBinaryInputStream::ReadUtf8Z(PRUnichar* *aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsBinaryInputStream::ReadBytes(char* *aString, PRUint32 aLength)
{
nsresult rv;
PRUint32 bytesRead;
char* s;
s = (char*)nsAllocator::Alloc(aLength);
if (!s)
return NS_ERROR_OUT_OF_MEMORY;
rv = Read(s, aLength, &bytesRead);
if (NS_FAILED(rv)) return rv;
if (bytesRead != aLength)
return NS_ERROR_FAILURE;
*aString = s;
return NS_OK;
}
NS_IMETHODIMP
nsBinaryInputStream::ReadString(nsString* *aString)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_COM nsresult
NS_NewBinaryOutputStream(nsIBinaryOutputStream* *aResult, nsIOutputStream* aDestStream)
{
NS_ENSURE_ARG_POINTER(aResult);
nsIBinaryOutputStream *stream = new nsBinaryOutputStream(aDestStream);
if (!stream)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(stream);
*aResult = stream;
return NS_OK;
}
NS_COM nsresult
NS_NewBinaryInputStream(nsIBinaryInputStream* *aResult, nsIInputStream* aSrcStream)
{
NS_ENSURE_ARG_POINTER(aResult);
nsIBinaryInputStream *stream = new nsBinaryInputStream(aSrcStream);
if (!stream)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(stream);
*aResult = stream;
return NS_OK;
}