gecko-dev/xpcom/io/nsByteBufferInputStream.cpp

387 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#include "nsByteBufferInputStream.h"
#include "prcmon.h"
NS_IMETHODIMP
nsDummyBufferStream::QueryInterface(REFNSIID aIID, void** aInstancePtr)
{
NS_NOTREACHED("nsDummyBufferStream::QueryInterface");
return NS_ERROR_FAILURE;
}
NS_IMETHODIMP_(nsrefcnt)
nsDummyBufferStream::AddRef(void)
{
NS_NOTREACHED("nsDummyBufferStream::AddRef");
return 1;
}
NS_IMETHODIMP_(nsrefcnt)
nsDummyBufferStream::Release(void)
{
NS_NOTREACHED("nsDummyBufferStream::Release");
return 1;
}
////////////////////////////////////////////////////////////////////////////////
// nsByteBufferInputStream methods:
////////////////////////////////////////////////////////////////////////////////
nsByteBufferInputStream::nsByteBufferInputStream(PRBool blocking, PRUint32 size)
: mBuffer(nsnull), mLength(size), mReadCursor(0), mWriteCursor(0),
mFull(PR_FALSE), mClosed(PR_FALSE), mEOF(PR_FALSE), mBlocking(blocking)
{
NS_INIT_REFCNT();
}
nsresult
nsByteBufferInputStream::Init(void)
{
mBuffer = new char[mLength];
if (mBuffer == nsnull)
return NS_ERROR_OUT_OF_MEMORY;
return NS_OK;
}
nsByteBufferInputStream::~nsByteBufferInputStream()
{
(void)Close();
if (mBuffer) delete mBuffer;
}
NS_IMPL_ISUPPORTS3(nsByteBufferInputStream, nsIByteBufferInputStream, nsIInputStream, nsIBaseStream)
NS_IMETHODIMP
nsByteBufferInputStream::Close(void)
{
nsresult rv = NS_OK;
if (mBlocking)
PR_CEnterMonitor(this);
mClosed = PR_TRUE;
if (mBlocking) {
PRStatus status = PR_CNotify(this); // wake up the writer
if (status != PR_SUCCESS)
rv = NS_ERROR_FAILURE;
PR_CExitMonitor(this);
}
return rv;
}
NS_IMETHODIMP
nsByteBufferInputStream::GetLength(PRUint32 *aLength)
{
if (mClosed)
return NS_BASE_STREAM_CLOSED;
if (mBlocking)
PR_CEnterMonitor(this);
*aLength = ReadableAmount();
if (mBlocking)
PR_CExitMonitor(this);
return NS_OK;
}
NS_IMETHODIMP
nsByteBufferInputStream::Read(char* aBuf, PRUint32 aCount, PRUint32 *aReadCount)
{
nsresult rv = NS_OK;
if (mClosed)
return NS_BASE_STREAM_CLOSED;
if (AtEOF())
return NS_BASE_STREAM_EOF;
if (mBlocking)
PR_CEnterMonitor(this);
*aReadCount = 0;
/*while (aCount > 0)*/ {
if (ReadableAmount() == 0) {
if (mBlocking) {
PRStatus status = PR_CWait(this, PR_INTERVAL_NO_TIMEOUT);
if (status != PR_SUCCESS) {
rv = NS_ERROR_FAILURE;
goto done;
}
}
if (mEOF) {
rv = NS_BASE_STREAM_EOF;
goto done;
}
else if (!mBlocking) {
rv = NS_BASE_STREAM_WOULD_BLOCK;
goto done;
}
}
// wrap-around buffer:
PRUint32 amt = 0;
if (mReadCursor >= mWriteCursor || mFull) {
ReadChunk(aBuf, aCount, mLength, &amt);
*aReadCount += amt;
aBuf += amt;
aCount -= amt;
if (mReadCursor == mLength) {
mReadCursor = 0;
amt = 0;
ReadChunk(aBuf, aCount, mWriteCursor, &amt);
*aReadCount += amt;
aBuf += amt;
aCount -= amt;
}
}
else {
ReadChunk(aBuf, aCount, mWriteCursor, &amt);
*aReadCount += amt;
aBuf += amt;
aCount -= amt;
}
if (*aReadCount)
mFull = PR_FALSE;
if (mBlocking) {
PRStatus status = PR_CNotify(this); // tell the writer there's space
if (status != PR_SUCCESS)
rv = NS_ERROR_FAILURE;
}
}
done:
if (mBlocking)
PR_CExitMonitor(this);
return rv;
}
NS_IMETHODIMP
nsByteBufferInputStream::Fill(const char* aBuf, PRUint32 aCount, PRUint32 *aWriteCount)
{
nsDummyBufferStream in(aBuf, aCount);
return Fill(&in, aCount, aWriteCount);
}
NS_IMETHODIMP
nsByteBufferInputStream::Fill(nsIInputStream* stream, PRUint32 aCount, PRUint32 *aWriteCount)
{
nsresult rv = NS_OK;
if (mClosed || mEOF)
return NS_BASE_STREAM_CLOSED;
*aWriteCount = 0;
if (mBlocking)
PR_CEnterMonitor(this);
while (aCount > 0) {
if (WritableAmount() == 0) {
if (mBlocking) {
PRStatus status = PR_CWait(this, PR_INTERVAL_NO_TIMEOUT);
if (status != PR_SUCCESS) {
rv = NS_ERROR_FAILURE;
goto done;
}
}
if (mClosed) {
rv = NS_BASE_STREAM_CLOSED;
goto done;
}
else if (!mBlocking) {
rv = NS_BASE_STREAM_WOULD_BLOCK;
goto done;
}
}
// wrap-around buffer:
PRUint32 amt = 0;
if (mReadCursor <= mWriteCursor && !mFull) {
rv = WriteChunk(stream, mLength, &amt);
if (NS_FAILED(rv)) goto done;
*aWriteCount += amt;
aCount -= amt;
if (mWriteCursor == mLength) {
mWriteCursor = 0;
amt = 0;
rv = WriteChunk(stream, mReadCursor, &amt);
if (NS_FAILED(rv)) goto done;
*aWriteCount += amt;
aCount -= amt;
}
}
else {
rv = WriteChunk(stream, mReadCursor, &amt);
if (NS_FAILED(rv)) goto done;
*aWriteCount += amt;
aCount -= amt;
}
if (mWriteCursor == mReadCursor)
mFull = PR_TRUE;
if (mBlocking) {
PRStatus status = PR_CNotify(this); // tell the reader there's more
if (status != PR_SUCCESS)
rv = NS_ERROR_FAILURE;
}
}
done:
if (mBlocking)
PR_CExitMonitor(this);
return rv;
}
nsresult
nsByteBufferInputStream::SetEOF()
{
nsresult rv = NS_OK;
if (mBlocking)
PR_CEnterMonitor(this);
mEOF = PR_TRUE;
if (mBlocking) {
PRStatus status = PR_CNotify(this); // wake up the reader
if (status != PR_SUCCESS)
rv = NS_ERROR_FAILURE;
PR_CExitMonitor(this);
}
return rv;
}
nsresult
nsByteBufferInputStream::Drain()
{
nsresult rv = NS_OK;
if (mBlocking) {
PR_CEnterMonitor(this);
while (ReadableAmount() != 0) {
PRStatus status = PR_CNotify(this); // wake up the reader
if (status != PR_SUCCESS) {
rv = NS_ERROR_FAILURE;
break;
}
else {
// wait for the reader to take all the data
status = PR_CWait(this, PR_INTERVAL_NO_TIMEOUT);
if (status != PR_SUCCESS) {
rv = NS_ERROR_FAILURE;
break;
}
}
}
PR_CExitMonitor(this);
}
return rv;
}
////////////////////////////////////////////////////////////////////////////////
// nsByteBufferOutputStream methods:
////////////////////////////////////////////////////////////////////////////////
nsByteBufferOutputStream::nsByteBufferOutputStream(nsByteBufferInputStream* in)
: mInputStream(in)
{
NS_INIT_REFCNT();
NS_ADDREF(mInputStream);
}
nsByteBufferOutputStream::~nsByteBufferOutputStream()
{
(void)Close();
NS_IF_RELEASE(mInputStream);
}
NS_IMPL_ISUPPORTS2(nsByteBufferOutputStream, nsIOutputStream, nsIBaseStream)
NS_IMETHODIMP
nsByteBufferOutputStream::Close(void)
{
mInputStream->SetEOF();
return NS_OK;
}
NS_IMETHODIMP
nsByteBufferOutputStream::Write(const char* aBuf, PRUint32 aCount,
PRUint32 *aWriteCount)
{
return mInputStream->Fill(aBuf, aCount, aWriteCount);
}
NS_IMETHODIMP
nsByteBufferOutputStream::WriteFrom(nsIInputStream* fromStream, PRUint32 aCount,
PRUint32 *aWriteCount)
{
return mInputStream->Fill(fromStream, aCount, aWriteCount);
}
NS_IMETHODIMP
nsByteBufferOutputStream::Flush(void)
{
return mInputStream->Drain();
}
////////////////////////////////////////////////////////////////////////////////
NS_COM nsresult
NS_NewByteBufferInputStream(nsIByteBufferInputStream* *result,
PRBool blocking, PRUint32 size)
{
nsresult rv;
nsByteBufferInputStream* inStr = nsnull;
inStr = new nsByteBufferInputStream(blocking, size);
if (inStr == nsnull)
return NS_ERROR_OUT_OF_MEMORY;
rv = inStr->Init();
if (NS_FAILED(rv)) {
delete inStr;
return rv;
}
NS_ADDREF(inStr);
*result = inStr;
return NS_OK;
}
////////////////////////////////////////////////////////////////////////////////
NS_COM nsresult
NS_NewPipe(nsIInputStream* *inStrResult,
nsIOutputStream* *outStrResult,
PRBool blocking, PRUint32 size)
{
nsresult rv;
nsIByteBufferInputStream* in;
nsByteBufferInputStream* inStr;
nsByteBufferOutputStream* outStr;
rv = NS_NewByteBufferInputStream(&in, blocking, size);
if (NS_FAILED(rv)) return rv;
// this cast is safe, because we know how NS_NewByteBufferInputStream works:
inStr = NS_STATIC_CAST(nsByteBufferInputStream*, in);
outStr = new nsByteBufferOutputStream(inStr);
if (outStr == nsnull) {
NS_RELEASE(inStr);
return NS_ERROR_OUT_OF_MEMORY;
}
NS_ADDREF(outStr);
*inStrResult = inStr;
*outStrResult = outStr;
return NS_OK;
}
////////////////////////////////////////////////////////////////////////////////