michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include <stdlib.h>
michael@0: #include "prlog.h"
michael@0: 
michael@0: #include "mozilla/Mutex.h"
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "nsIInputStreamTee.h"
michael@0: #include "nsIInputStream.h"
michael@0: #include "nsIOutputStream.h"
michael@0: #include "nsCOMPtr.h"
michael@0: #include "nsAutoPtr.h"
michael@0: #include "nsIEventTarget.h"
michael@0: #include "nsThreadUtils.h"
michael@0: 
michael@0: using namespace mozilla;
michael@0: 
michael@0: #ifdef LOG
michael@0: #undef LOG
michael@0: #endif
michael@0: #ifdef PR_LOGGING
michael@0: static PRLogModuleInfo*
michael@0: GetTeeLog()
michael@0: {
michael@0:     static PRLogModuleInfo *sLog;
michael@0:     if (!sLog)
michael@0:         sLog = PR_NewLogModule("nsInputStreamTee");
michael@0:     return sLog;
michael@0: }
michael@0: #define LOG(args) PR_LOG(GetTeeLog(), PR_LOG_DEBUG, args)
michael@0: #else
michael@0: #define LOG(args)
michael@0: #endif
michael@0: 
michael@0: class nsInputStreamTee MOZ_FINAL : public nsIInputStreamTee
michael@0: {
michael@0: public:
michael@0:     NS_DECL_THREADSAFE_ISUPPORTS
michael@0:     NS_DECL_NSIINPUTSTREAM
michael@0:     NS_DECL_NSIINPUTSTREAMTEE
michael@0: 
michael@0:     nsInputStreamTee();
michael@0:     bool SinkIsValid();
michael@0:     void InvalidateSink();
michael@0: 
michael@0: private:
michael@0:     ~nsInputStreamTee() {}
michael@0: 
michael@0:     nsresult TeeSegment(const char *buf, uint32_t count);
michael@0:     
michael@0:     static NS_METHOD WriteSegmentFun(nsIInputStream *, void *, const char *,
michael@0:                                      uint32_t, uint32_t, uint32_t *);
michael@0: 
michael@0: private:
michael@0:     nsCOMPtr<nsIInputStream>  mSource;
michael@0:     nsCOMPtr<nsIOutputStream> mSink;
michael@0:     nsCOMPtr<nsIEventTarget>  mEventTarget;
michael@0:     nsWriteSegmentFun         mWriter;  // for implementing ReadSegments
michael@0:     void                      *mClosure; // for implementing ReadSegments
michael@0:     nsAutoPtr<Mutex>          mLock; // synchronize access to mSinkIsValid
michael@0:     bool                      mSinkIsValid; // False if TeeWriteEvent fails 
michael@0: };
michael@0: 
michael@0: class nsInputStreamTeeWriteEvent : public nsRunnable {
michael@0: public:
michael@0:     // aTee's lock is held across construction of this object
michael@0:     nsInputStreamTeeWriteEvent(const char *aBuf, uint32_t aCount,
michael@0:                                nsIOutputStream  *aSink, 
michael@0:                                nsInputStreamTee *aTee)
michael@0:     {
michael@0:         // copy the buffer - will be free'd by dtor
michael@0:         mBuf = (char *)malloc(aCount);
michael@0:         if (mBuf) memcpy(mBuf, (char *)aBuf, aCount);
michael@0:         mCount = aCount;
michael@0:         mSink = aSink;
michael@0:         bool isNonBlocking;
michael@0:         mSink->IsNonBlocking(&isNonBlocking);
michael@0:         NS_ASSERTION(isNonBlocking == false, "mSink is nonblocking");
michael@0:         mTee = aTee;
michael@0:     }
michael@0: 
michael@0:     NS_IMETHOD Run()
michael@0:     {
michael@0:         if (!mBuf) {
michael@0:             NS_WARNING("nsInputStreamTeeWriteEvent::Run() "
michael@0:                        "memory not allocated\n");
michael@0:             return NS_OK;
michael@0:         }
michael@0:         NS_ABORT_IF_FALSE(mSink, "mSink is null!");
michael@0: 
michael@0:         //  The output stream could have been invalidated between when 
michael@0:         //  this event was dispatched and now, so check before writing.
michael@0:         if (!mTee->SinkIsValid()) {
michael@0:             return NS_OK; 
michael@0:         }
michael@0: 
michael@0:         LOG(("nsInputStreamTeeWriteEvent::Run() [%p]"
michael@0:              "will write %u bytes to %p\n",
michael@0:               this, mCount, mSink.get()));
michael@0: 
michael@0:         uint32_t totalBytesWritten = 0;
michael@0:         while (mCount) {
michael@0:             nsresult rv;
michael@0:             uint32_t bytesWritten = 0;
michael@0:             rv = mSink->Write(mBuf + totalBytesWritten, mCount, &bytesWritten);
michael@0:             if (NS_FAILED(rv)) {
michael@0:                 LOG(("nsInputStreamTeeWriteEvent::Run[%p] error %x in writing",
michael@0:                      this,rv));
michael@0:                 mTee->InvalidateSink();
michael@0:                 break;
michael@0:             }
michael@0:             totalBytesWritten += bytesWritten;
michael@0:             NS_ASSERTION(bytesWritten <= mCount, "wrote too much");
michael@0:             mCount -= bytesWritten;
michael@0:         }
michael@0:         return NS_OK;
michael@0:     }
michael@0: 
michael@0: protected:
michael@0:     virtual ~nsInputStreamTeeWriteEvent()
michael@0:     {
michael@0:         if (mBuf) free(mBuf);
michael@0:         mBuf = nullptr;
michael@0:     }
michael@0:     
michael@0: private:
michael@0:     char *mBuf;
michael@0:     uint32_t mCount;
michael@0:     nsCOMPtr<nsIOutputStream> mSink;
michael@0:     // back pointer to the tee that created this runnable
michael@0:     nsRefPtr<nsInputStreamTee> mTee;
michael@0: };
michael@0: 
michael@0: nsInputStreamTee::nsInputStreamTee(): mLock(nullptr)
michael@0:                                     , mSinkIsValid(true)
michael@0: {
michael@0: }
michael@0: 
michael@0: bool
michael@0: nsInputStreamTee::SinkIsValid()
michael@0: {
michael@0:     MutexAutoLock lock(*mLock); 
michael@0:     return mSinkIsValid; 
michael@0: }
michael@0: 
michael@0: void
michael@0: nsInputStreamTee::InvalidateSink()
michael@0: {
michael@0:     MutexAutoLock lock(*mLock);
michael@0:     mSinkIsValid = false;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsInputStreamTee::TeeSegment(const char *buf, uint32_t count)
michael@0: {
michael@0:     if (!mSink) return NS_OK; // nothing to do
michael@0:     if (mLock) { // asynchronous case
michael@0:         NS_ASSERTION(mEventTarget, "mEventTarget is null, mLock is not null.");
michael@0:         if (!SinkIsValid()) {
michael@0:             return NS_OK; // nothing to do
michael@0:         }
michael@0:         nsRefPtr<nsIRunnable> event =
michael@0:             new nsInputStreamTeeWriteEvent(buf, count, mSink, this);
michael@0:         LOG(("nsInputStreamTee::TeeSegment [%p] dispatching write %u bytes\n",
michael@0:               this, count));
michael@0:         return mEventTarget->Dispatch(event, NS_DISPATCH_NORMAL);
michael@0:     } else { // synchronous case
michael@0:         NS_ASSERTION(!mEventTarget, "mEventTarget is not null, mLock is null.");
michael@0:         nsresult rv;
michael@0:         uint32_t totalBytesWritten = 0;
michael@0:         while (count) {
michael@0:             uint32_t bytesWritten = 0;
michael@0:             rv = mSink->Write(buf + totalBytesWritten, count, &bytesWritten);
michael@0:             if (NS_FAILED(rv)) {
michael@0:                 // ok, this is not a fatal error... just drop our reference to mSink
michael@0:                 // and continue on as if nothing happened.
michael@0:                 NS_WARNING("Write failed (non-fatal)");
michael@0:                 // catch possible misuse of the input stream tee
michael@0:                 NS_ASSERTION(rv != NS_BASE_STREAM_WOULD_BLOCK, "sink must be a blocking stream");
michael@0:                 mSink = 0;
michael@0:                 break;
michael@0:             }
michael@0:             totalBytesWritten += bytesWritten;
michael@0:             NS_ASSERTION(bytesWritten <= count, "wrote too much");
michael@0:             count -= bytesWritten;
michael@0:         }
michael@0:         return NS_OK;
michael@0:     }
michael@0: }
michael@0: 
michael@0: NS_METHOD
michael@0: nsInputStreamTee::WriteSegmentFun(nsIInputStream *in, void *closure, const char *fromSegment,
michael@0:                                   uint32_t offset, uint32_t count, uint32_t *writeCount)
michael@0: {
michael@0:     nsInputStreamTee *tee = reinterpret_cast<nsInputStreamTee *>(closure);
michael@0: 
michael@0:     nsresult rv = tee->mWriter(in, tee->mClosure, fromSegment, offset, count, writeCount);
michael@0:     if (NS_FAILED(rv) || (*writeCount == 0)) {
michael@0:         NS_ASSERTION((NS_FAILED(rv) ? (*writeCount == 0) : true),
michael@0:                 "writer returned an error with non-zero writeCount");
michael@0:         return rv;
michael@0:     }
michael@0: 
michael@0:     return tee->TeeSegment(fromSegment, *writeCount);
michael@0: }
michael@0: 
michael@0: NS_IMPL_ISUPPORTS(nsInputStreamTee,
michael@0:                   nsIInputStreamTee,
michael@0:                   nsIInputStream)
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::Close()
michael@0: {
michael@0:     if (NS_WARN_IF(!mSource))
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0:     nsresult rv = mSource->Close();
michael@0:     mSource = 0;
michael@0:     mSink = 0;
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::Available(uint64_t *avail)
michael@0: {
michael@0:     if (NS_WARN_IF(!mSource))
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0:     return mSource->Available(avail);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::Read(char *buf, uint32_t count, uint32_t *bytesRead)
michael@0: {
michael@0:     if (NS_WARN_IF(!mSource))
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     nsresult rv = mSource->Read(buf, count, bytesRead);
michael@0:     if (NS_FAILED(rv) || (*bytesRead == 0))
michael@0:         return rv;
michael@0: 
michael@0:     return TeeSegment(buf, *bytesRead);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::ReadSegments(nsWriteSegmentFun writer, 
michael@0:                                void *closure,
michael@0:                                uint32_t count,
michael@0:                                uint32_t *bytesRead)
michael@0: {
michael@0:     if (NS_WARN_IF(!mSource))
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0: 
michael@0:     mWriter = writer;
michael@0:     mClosure = closure;
michael@0: 
michael@0:     return mSource->ReadSegments(WriteSegmentFun, this, count, bytesRead);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::IsNonBlocking(bool *result)
michael@0: {
michael@0:     if (NS_WARN_IF(!mSource))
michael@0:         return NS_ERROR_NOT_INITIALIZED;
michael@0:     return mSource->IsNonBlocking(result);
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::SetSource(nsIInputStream *source)
michael@0: {
michael@0:     mSource = source;
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::GetSource(nsIInputStream **source)
michael@0: {
michael@0:     NS_IF_ADDREF(*source = mSource);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::SetSink(nsIOutputStream *sink)
michael@0: {
michael@0: #ifdef DEBUG
michael@0:     if (sink) {
michael@0:         bool nonBlocking;
michael@0:         nsresult rv = sink->IsNonBlocking(&nonBlocking);
michael@0:         if (NS_FAILED(rv) || nonBlocking)
michael@0:             NS_ERROR("sink should be a blocking stream");
michael@0:     }
michael@0: #endif
michael@0:     mSink = sink;
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::GetSink(nsIOutputStream **sink)
michael@0: {
michael@0:     NS_IF_ADDREF(*sink = mSink);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::SetEventTarget(nsIEventTarget *anEventTarget)
michael@0: {
michael@0:     mEventTarget = anEventTarget;
michael@0:     if (mEventTarget) {
michael@0:         // Only need synchronization if this is an async tee
michael@0:         mLock = new Mutex("nsInputStreamTee.mLock");
michael@0:     }
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP
michael@0: nsInputStreamTee::GetEventTarget(nsIEventTarget **anEventTarget)
michael@0: {
michael@0:     NS_IF_ADDREF(*anEventTarget = mEventTarget);
michael@0:     return NS_OK;
michael@0: }
michael@0: 
michael@0: 
michael@0: nsresult
michael@0: NS_NewInputStreamTeeAsync(nsIInputStream **result,
michael@0:                           nsIInputStream *source,
michael@0:                           nsIOutputStream *sink,
michael@0:                           nsIEventTarget *anEventTarget)
michael@0: {
michael@0:     nsresult rv;
michael@0:     
michael@0:     nsCOMPtr<nsIInputStreamTee> tee = new nsInputStreamTee();
michael@0:     if (!tee)
michael@0:         return NS_ERROR_OUT_OF_MEMORY;
michael@0: 
michael@0:     rv = tee->SetSource(source);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = tee->SetSink(sink);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     rv = tee->SetEventTarget(anEventTarget);
michael@0:     if (NS_FAILED(rv)) return rv;
michael@0: 
michael@0:     NS_ADDREF(*result = tee);
michael@0:     return rv;
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: NS_NewInputStreamTee(nsIInputStream **result,
michael@0:                      nsIInputStream *source,
michael@0:                      nsIOutputStream *sink)
michael@0: {
michael@0:     return NS_NewInputStreamTeeAsync(result, source, sink, nullptr);
michael@0: }
michael@0: 
michael@0: #undef LOG