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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /netwerk/base/nsBufferedStreams.cpp
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'netwerk/base/nsBufferedStreams.cpp')
-rw-r--r--netwerk/base/nsBufferedStreams.cpp832
1 files changed, 832 insertions, 0 deletions
diff --git a/netwerk/base/nsBufferedStreams.cpp b/netwerk/base/nsBufferedStreams.cpp
new file mode 100644
index 000000000..e67c3009b
--- /dev/null
+++ b/netwerk/base/nsBufferedStreams.cpp
@@ -0,0 +1,832 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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/. */
+
+#include "ipc/IPCMessageUtils.h"
+
+#include "nsBufferedStreams.h"
+#include "nsStreamUtils.h"
+#include "nsNetCID.h"
+#include "nsIClassInfoImpl.h"
+#include "mozilla/ipc/InputStreamUtils.h"
+#include <algorithm>
+
+#ifdef DEBUG_brendan
+# define METERING
+#endif
+
+#ifdef METERING
+# include <stdio.h>
+# define METER(x) x
+# define MAX_BIG_SEEKS 20
+
+static struct {
+ uint32_t mSeeksWithinBuffer;
+ uint32_t mSeeksOutsideBuffer;
+ uint32_t mBufferReadUponSeek;
+ uint32_t mBufferUnreadUponSeek;
+ uint32_t mBytesReadFromBuffer;
+ uint32_t mBigSeekIndex;
+ struct {
+ int64_t mOldOffset;
+ int64_t mNewOffset;
+ } mBigSeek[MAX_BIG_SEEKS];
+} bufstats;
+#else
+# define METER(x) /* nothing */
+#endif
+
+using namespace mozilla::ipc;
+using mozilla::Maybe;
+using mozilla::Nothing;
+using mozilla::Some;
+
+////////////////////////////////////////////////////////////////////////////////
+// nsBufferedStream
+
+nsBufferedStream::nsBufferedStream()
+ : mBuffer(nullptr),
+ mBufferStartOffset(0),
+ mCursor(0),
+ mFillPoint(0),
+ mStream(nullptr),
+ mBufferDisabled(false),
+ mEOF(false),
+ mGetBufferCount(0)
+{
+}
+
+nsBufferedStream::~nsBufferedStream()
+{
+ Close();
+}
+
+NS_IMPL_ISUPPORTS(nsBufferedStream, nsISeekableStream)
+
+nsresult
+nsBufferedStream::Init(nsISupports* stream, uint32_t bufferSize)
+{
+ NS_ASSERTION(stream, "need to supply a stream");
+ NS_ASSERTION(mStream == nullptr, "already inited");
+ mStream = stream;
+ NS_IF_ADDREF(mStream);
+ mBufferSize = bufferSize;
+ mBufferStartOffset = 0;
+ mCursor = 0;
+ mBuffer = new (mozilla::fallible) char[bufferSize];
+ if (mBuffer == nullptr)
+ return NS_ERROR_OUT_OF_MEMORY;
+ return NS_OK;
+}
+
+nsresult
+nsBufferedStream::Close()
+{
+ NS_IF_RELEASE(mStream);
+ if (mBuffer) {
+ delete[] mBuffer;
+ mBuffer = nullptr;
+ mBufferSize = 0;
+ mBufferStartOffset = 0;
+ mCursor = 0;
+ mFillPoint = 0;
+ }
+#ifdef METERING
+ {
+ static FILE *tfp;
+ if (!tfp) {
+ tfp = fopen("/tmp/bufstats", "w");
+ if (tfp)
+ setvbuf(tfp, nullptr, _IOLBF, 0);
+ }
+ if (tfp) {
+ fprintf(tfp, "seeks within buffer: %u\n",
+ bufstats.mSeeksWithinBuffer);
+ fprintf(tfp, "seeks outside buffer: %u\n",
+ bufstats.mSeeksOutsideBuffer);
+ fprintf(tfp, "buffer read on seek: %u\n",
+ bufstats.mBufferReadUponSeek);
+ fprintf(tfp, "buffer unread on seek: %u\n",
+ bufstats.mBufferUnreadUponSeek);
+ fprintf(tfp, "bytes read from buffer: %u\n",
+ bufstats.mBytesReadFromBuffer);
+ for (uint32_t i = 0; i < bufstats.mBigSeekIndex; i++) {
+ fprintf(tfp, "bigseek[%u] = {old: %u, new: %u}\n",
+ i,
+ bufstats.mBigSeek[i].mOldOffset,
+ bufstats.mBigSeek[i].mNewOffset);
+ }
+ }
+ }
+#endif
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedStream::Seek(int32_t whence, int64_t offset)
+{
+ if (mStream == nullptr)
+ return NS_BASE_STREAM_CLOSED;
+
+ // If the underlying stream isn't a random access store, then fail early.
+ // We could possibly succeed for the case where the seek position denotes
+ // something that happens to be read into the buffer, but that would make
+ // the failure data-dependent.
+ nsresult rv;
+ nsCOMPtr<nsISeekableStream> ras = do_QueryInterface(mStream, &rv);
+ if (NS_FAILED(rv)) return rv;
+
+ int64_t absPos = 0;
+ switch (whence) {
+ case nsISeekableStream::NS_SEEK_SET:
+ absPos = offset;
+ break;
+ case nsISeekableStream::NS_SEEK_CUR:
+ absPos = mBufferStartOffset;
+ absPos += mCursor;
+ absPos += offset;
+ break;
+ case nsISeekableStream::NS_SEEK_END:
+ absPos = -1;
+ break;
+ default:
+ NS_NOTREACHED("bogus seek whence parameter");
+ return NS_ERROR_UNEXPECTED;
+ }
+
+ // Let mCursor point into the existing buffer if the new position is
+ // between the current cursor and the mFillPoint "fencepost" -- the
+ // client may never get around to a Read or Write after this Seek.
+ // Read and Write worry about flushing and filling in that event.
+ // But if we're at EOF, make sure to pass the seek through to the
+ // underlying stream, because it may have auto-closed itself and
+ // needs to reopen.
+ uint32_t offsetInBuffer = uint32_t(absPos - mBufferStartOffset);
+ if (offsetInBuffer <= mFillPoint && !mEOF) {
+ METER(bufstats.mSeeksWithinBuffer++);
+ mCursor = offsetInBuffer;
+ return NS_OK;
+ }
+
+ METER(bufstats.mSeeksOutsideBuffer++);
+ METER(bufstats.mBufferReadUponSeek += mCursor);
+ METER(bufstats.mBufferUnreadUponSeek += mFillPoint - mCursor);
+ rv = Flush();
+ if (NS_FAILED(rv)) return rv;
+
+ rv = ras->Seek(whence, offset);
+ if (NS_FAILED(rv)) return rv;
+
+ mEOF = false;
+
+ // Recompute whether the offset we're seeking to is in our buffer.
+ // Note that we need to recompute because Flush() might have
+ // changed mBufferStartOffset.
+ offsetInBuffer = uint32_t(absPos - mBufferStartOffset);
+ if (offsetInBuffer <= mFillPoint) {
+ // It's safe to just set mCursor to offsetInBuffer. In particular, we
+ // want to avoid calling Fill() here since we already have the data that
+ // was seeked to and calling Fill() might auto-close our underlying
+ // stream in some cases.
+ mCursor = offsetInBuffer;
+ return NS_OK;
+ }
+
+ METER(if (bufstats.mBigSeekIndex < MAX_BIG_SEEKS)
+ bufstats.mBigSeek[bufstats.mBigSeekIndex].mOldOffset =
+ mBufferStartOffset + int64_t(mCursor));
+ const int64_t minus1 = -1;
+ if (absPos == minus1) {
+ // then we had the SEEK_END case, above
+ int64_t tellPos;
+ rv = ras->Tell(&tellPos);
+ mBufferStartOffset = tellPos;
+ if (NS_FAILED(rv)) return rv;
+ }
+ else {
+ mBufferStartOffset = absPos;
+ }
+ METER(if (bufstats.mBigSeekIndex < MAX_BIG_SEEKS)
+ bufstats.mBigSeek[bufstats.mBigSeekIndex++].mNewOffset =
+ mBufferStartOffset);
+
+ mFillPoint = mCursor = 0;
+ return Fill();
+}
+
+NS_IMETHODIMP
+nsBufferedStream::Tell(int64_t *result)
+{
+ if (mStream == nullptr)
+ return NS_BASE_STREAM_CLOSED;
+
+ int64_t result64 = mBufferStartOffset;
+ result64 += mCursor;
+ *result = result64;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedStream::SetEOF()
+{
+ if (mStream == nullptr)
+ return NS_BASE_STREAM_CLOSED;
+
+ nsresult rv;
+ nsCOMPtr<nsISeekableStream> ras = do_QueryInterface(mStream, &rv);
+ if (NS_FAILED(rv)) return rv;
+
+ rv = ras->SetEOF();
+ if (NS_SUCCEEDED(rv))
+ mEOF = true;
+ return rv;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsBufferedInputStream
+
+NS_IMPL_ADDREF_INHERITED(nsBufferedInputStream, nsBufferedStream)
+NS_IMPL_RELEASE_INHERITED(nsBufferedInputStream, nsBufferedStream)
+
+NS_IMPL_CLASSINFO(nsBufferedInputStream, nullptr, nsIClassInfo::THREADSAFE,
+ NS_BUFFEREDINPUTSTREAM_CID)
+
+NS_INTERFACE_MAP_BEGIN(nsBufferedInputStream)
+ NS_INTERFACE_MAP_ENTRY(nsIInputStream)
+ NS_INTERFACE_MAP_ENTRY(nsIBufferedInputStream)
+ NS_INTERFACE_MAP_ENTRY(nsIStreamBufferAccess)
+ NS_INTERFACE_MAP_ENTRY(nsIIPCSerializableInputStream)
+ NS_IMPL_QUERY_CLASSINFO(nsBufferedInputStream)
+NS_INTERFACE_MAP_END_INHERITING(nsBufferedStream)
+
+NS_IMPL_CI_INTERFACE_GETTER(nsBufferedInputStream,
+ nsIInputStream,
+ nsIBufferedInputStream,
+ nsISeekableStream,
+ nsIStreamBufferAccess)
+
+nsresult
+nsBufferedInputStream::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+ NS_ENSURE_NO_AGGREGATION(aOuter);
+
+ nsBufferedInputStream* stream = new nsBufferedInputStream();
+ if (stream == nullptr)
+ return NS_ERROR_OUT_OF_MEMORY;
+ NS_ADDREF(stream);
+ nsresult rv = stream->QueryInterface(aIID, aResult);
+ NS_RELEASE(stream);
+ return rv;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::Init(nsIInputStream* stream, uint32_t bufferSize)
+{
+ return nsBufferedStream::Init(stream, bufferSize);
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::Close()
+{
+ nsresult rv1 = NS_OK, rv2;
+ if (mStream) {
+ rv1 = Source()->Close();
+ NS_RELEASE(mStream);
+ }
+ rv2 = nsBufferedStream::Close();
+ if (NS_FAILED(rv1)) return rv1;
+ return rv2;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::Available(uint64_t *result)
+{
+ nsresult rv = NS_OK;
+ *result = 0;
+ if (mStream) {
+ rv = Source()->Available(result);
+ }
+ *result += (mFillPoint - mCursor);
+ return rv;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::Read(char * buf, uint32_t count, uint32_t *result)
+{
+ if (mBufferDisabled) {
+ if (!mStream) {
+ *result = 0;
+ return NS_OK;
+ }
+ nsresult rv = Source()->Read(buf, count, result);
+ if (NS_SUCCEEDED(rv)) {
+ mBufferStartOffset += *result; // so nsBufferedStream::Tell works
+ if (*result == 0) {
+ mEOF = true;
+ }
+ }
+ return rv;
+ }
+
+ return ReadSegments(NS_CopySegmentToBuffer, buf, count, result);
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::ReadSegments(nsWriteSegmentFun writer, void *closure,
+ uint32_t count, uint32_t *result)
+{
+ *result = 0;
+
+ if (!mStream)
+ return NS_OK;
+
+ nsresult rv = NS_OK;
+ while (count > 0) {
+ uint32_t amt = std::min(count, mFillPoint - mCursor);
+ if (amt > 0) {
+ uint32_t read = 0;
+ rv = writer(this, closure, mBuffer + mCursor, *result, amt, &read);
+ if (NS_FAILED(rv)) {
+ // errors returned from the writer end here!
+ rv = NS_OK;
+ break;
+ }
+ *result += read;
+ count -= read;
+ mCursor += read;
+ }
+ else {
+ rv = Fill();
+ if (NS_FAILED(rv) || mFillPoint == mCursor)
+ break;
+ }
+ }
+ return (*result > 0) ? NS_OK : rv;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::IsNonBlocking(bool *aNonBlocking)
+{
+ if (mStream)
+ return Source()->IsNonBlocking(aNonBlocking);
+ return NS_ERROR_NOT_INITIALIZED;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::Fill()
+{
+ if (mBufferDisabled)
+ return NS_OK;
+ NS_ENSURE_TRUE(mStream, NS_ERROR_NOT_INITIALIZED);
+
+ nsresult rv;
+ int32_t rem = int32_t(mFillPoint - mCursor);
+ if (rem > 0) {
+ // slide the remainder down to the start of the buffer
+ // |<------------->|<--rem-->|<--->|
+ // b c f s
+ memcpy(mBuffer, mBuffer + mCursor, rem);
+ }
+ mBufferStartOffset += mCursor;
+ mFillPoint = rem;
+ mCursor = 0;
+
+ uint32_t amt;
+ rv = Source()->Read(mBuffer + mFillPoint, mBufferSize - mFillPoint, &amt);
+ if (NS_FAILED(rv)) return rv;
+
+ if (amt == 0)
+ mEOF = true;
+
+ mFillPoint += amt;
+ return NS_OK;
+}
+
+NS_IMETHODIMP_(char*)
+nsBufferedInputStream::GetBuffer(uint32_t aLength, uint32_t aAlignMask)
+{
+ NS_ASSERTION(mGetBufferCount == 0, "nested GetBuffer!");
+ if (mGetBufferCount != 0)
+ return nullptr;
+
+ if (mBufferDisabled)
+ return nullptr;
+
+ char* buf = mBuffer + mCursor;
+ uint32_t rem = mFillPoint - mCursor;
+ if (rem == 0) {
+ if (NS_FAILED(Fill()))
+ return nullptr;
+ buf = mBuffer + mCursor;
+ rem = mFillPoint - mCursor;
+ }
+
+ uint32_t mod = (NS_PTR_TO_INT32(buf) & aAlignMask);
+ if (mod) {
+ uint32_t pad = aAlignMask + 1 - mod;
+ if (pad > rem)
+ return nullptr;
+
+ memset(buf, 0, pad);
+ mCursor += pad;
+ buf += pad;
+ rem -= pad;
+ }
+
+ if (aLength > rem)
+ return nullptr;
+ mGetBufferCount++;
+ return buf;
+}
+
+NS_IMETHODIMP_(void)
+nsBufferedInputStream::PutBuffer(char* aBuffer, uint32_t aLength)
+{
+ NS_ASSERTION(mGetBufferCount == 1, "stray PutBuffer!");
+ if (--mGetBufferCount != 0)
+ return;
+
+ NS_ASSERTION(mCursor + aLength <= mFillPoint, "PutBuffer botch");
+ mCursor += aLength;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::DisableBuffering()
+{
+ NS_ASSERTION(!mBufferDisabled, "redundant call to DisableBuffering!");
+ NS_ASSERTION(mGetBufferCount == 0,
+ "DisableBuffer call between GetBuffer and PutBuffer!");
+ if (mGetBufferCount != 0)
+ return NS_ERROR_UNEXPECTED;
+
+ // Empty the buffer so nsBufferedStream::Tell works.
+ mBufferStartOffset += mCursor;
+ mFillPoint = mCursor = 0;
+ mBufferDisabled = true;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::EnableBuffering()
+{
+ NS_ASSERTION(mBufferDisabled, "gratuitous call to EnableBuffering!");
+ mBufferDisabled = false;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedInputStream::GetUnbufferedStream(nsISupports* *aStream)
+{
+ // Empty the buffer so subsequent i/o trumps any buffered data.
+ mBufferStartOffset += mCursor;
+ mFillPoint = mCursor = 0;
+
+ *aStream = mStream;
+ NS_IF_ADDREF(*aStream);
+ return NS_OK;
+}
+
+void
+nsBufferedInputStream::Serialize(InputStreamParams& aParams,
+ FileDescriptorArray& aFileDescriptors)
+{
+ BufferedInputStreamParams params;
+
+ if (mStream) {
+ nsCOMPtr<nsIInputStream> stream = do_QueryInterface(mStream);
+ MOZ_ASSERT(stream);
+
+ InputStreamParams wrappedParams;
+ SerializeInputStream(stream, wrappedParams, aFileDescriptors);
+
+ params.optionalStream() = wrappedParams;
+ }
+ else {
+ params.optionalStream() = mozilla::void_t();
+ }
+
+ params.bufferSize() = mBufferSize;
+
+ aParams = params;
+}
+
+bool
+nsBufferedInputStream::Deserialize(const InputStreamParams& aParams,
+ const FileDescriptorArray& aFileDescriptors)
+{
+ if (aParams.type() != InputStreamParams::TBufferedInputStreamParams) {
+ NS_ERROR("Received unknown parameters from the other process!");
+ return false;
+ }
+
+ const BufferedInputStreamParams& params =
+ aParams.get_BufferedInputStreamParams();
+ const OptionalInputStreamParams& wrappedParams = params.optionalStream();
+
+ nsCOMPtr<nsIInputStream> stream;
+ if (wrappedParams.type() == OptionalInputStreamParams::TInputStreamParams) {
+ stream = DeserializeInputStream(wrappedParams.get_InputStreamParams(),
+ aFileDescriptors);
+ if (!stream) {
+ NS_WARNING("Failed to deserialize wrapped stream!");
+ return false;
+ }
+ }
+ else {
+ NS_ASSERTION(wrappedParams.type() == OptionalInputStreamParams::Tvoid_t,
+ "Unknown type for OptionalInputStreamParams!");
+ }
+
+ nsresult rv = Init(stream, params.bufferSize());
+ NS_ENSURE_SUCCESS(rv, false);
+
+ return true;
+}
+
+Maybe<uint64_t>
+nsBufferedInputStream::ExpectedSerializedLength()
+{
+ nsCOMPtr<nsIIPCSerializableInputStream> stream = do_QueryInterface(mStream);
+ if (stream) {
+ return stream->ExpectedSerializedLength();
+ }
+ return Nothing();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// nsBufferedOutputStream
+
+NS_IMPL_ADDREF_INHERITED(nsBufferedOutputStream, nsBufferedStream)
+NS_IMPL_RELEASE_INHERITED(nsBufferedOutputStream, nsBufferedStream)
+// This QI uses NS_INTERFACE_MAP_ENTRY_CONDITIONAL to check for
+// non-nullness of mSafeStream.
+NS_INTERFACE_MAP_BEGIN(nsBufferedOutputStream)
+ NS_INTERFACE_MAP_ENTRY(nsIOutputStream)
+ NS_INTERFACE_MAP_ENTRY_CONDITIONAL(nsISafeOutputStream, mSafeStream)
+ NS_INTERFACE_MAP_ENTRY(nsIBufferedOutputStream)
+ NS_INTERFACE_MAP_ENTRY(nsIStreamBufferAccess)
+NS_INTERFACE_MAP_END_INHERITING(nsBufferedStream)
+
+nsresult
+nsBufferedOutputStream::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+ NS_ENSURE_NO_AGGREGATION(aOuter);
+
+ nsBufferedOutputStream* stream = new nsBufferedOutputStream();
+ if (stream == nullptr)
+ return NS_ERROR_OUT_OF_MEMORY;
+ NS_ADDREF(stream);
+ nsresult rv = stream->QueryInterface(aIID, aResult);
+ NS_RELEASE(stream);
+ return rv;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::Init(nsIOutputStream* stream, uint32_t bufferSize)
+{
+ // QI stream to an nsISafeOutputStream, to see if we should support it
+ mSafeStream = do_QueryInterface(stream);
+
+ return nsBufferedStream::Init(stream, bufferSize);
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::Close()
+{
+ nsresult rv1, rv2 = NS_OK, rv3;
+ rv1 = Flush();
+ // If we fail to Flush all the data, then we close anyway and drop the
+ // remaining data in the buffer. We do this because it's what Unix does
+ // for fclose and close. However, we report the error from Flush anyway.
+ if (mStream) {
+ rv2 = Sink()->Close();
+ NS_RELEASE(mStream);
+ }
+ rv3 = nsBufferedStream::Close();
+ if (NS_FAILED(rv1)) return rv1;
+ if (NS_FAILED(rv2)) return rv2;
+ return rv3;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::Write(const char *buf, uint32_t count, uint32_t *result)
+{
+ nsresult rv = NS_OK;
+ uint32_t written = 0;
+ while (count > 0) {
+ uint32_t amt = std::min(count, mBufferSize - mCursor);
+ if (amt > 0) {
+ memcpy(mBuffer + mCursor, buf + written, amt);
+ written += amt;
+ count -= amt;
+ mCursor += amt;
+ if (mFillPoint < mCursor)
+ mFillPoint = mCursor;
+ }
+ else {
+ NS_ASSERTION(mFillPoint, "iloop in nsBufferedOutputStream::Write!");
+ rv = Flush();
+ if (NS_FAILED(rv)) break;
+ }
+ }
+ *result = written;
+ return (written > 0) ? NS_OK : rv;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::Flush()
+{
+ nsresult rv;
+ uint32_t amt;
+ if (!mStream) {
+ // Stream already cancelled/flushed; probably because of previous error.
+ return NS_OK;
+ }
+ rv = Sink()->Write(mBuffer, mFillPoint, &amt);
+ if (NS_FAILED(rv)) return rv;
+ mBufferStartOffset += amt;
+ if (amt == mFillPoint) {
+ mFillPoint = mCursor = 0;
+ return NS_OK; // flushed everything
+ }
+
+ // slide the remainder down to the start of the buffer
+ // |<-------------->|<---|----->|
+ // b a c s
+ uint32_t rem = mFillPoint - amt;
+ memmove(mBuffer, mBuffer + amt, rem);
+ mFillPoint = mCursor = rem;
+ return NS_ERROR_FAILURE; // didn't flush all
+}
+
+// nsISafeOutputStream
+NS_IMETHODIMP
+nsBufferedOutputStream::Finish()
+{
+ // flush the stream, to write out any buffered data...
+ nsresult rv = nsBufferedOutputStream::Flush();
+ if (NS_FAILED(rv))
+ NS_WARNING("failed to flush buffered data! possible dataloss");
+
+ // ... and finish the underlying stream...
+ if (NS_SUCCEEDED(rv))
+ rv = mSafeStream->Finish();
+ else
+ Sink()->Close();
+
+ // ... and close the buffered stream, so any further attempts to flush/close
+ // the buffered stream won't cause errors.
+ nsBufferedStream::Close();
+
+ return rv;
+}
+
+static nsresult
+nsReadFromInputStream(nsIOutputStream* outStr,
+ void* closure,
+ char* toRawSegment,
+ uint32_t offset,
+ uint32_t count,
+ uint32_t *readCount)
+{
+ nsIInputStream* fromStream = (nsIInputStream*)closure;
+ return fromStream->Read(toRawSegment, count, readCount);
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::WriteFrom(nsIInputStream *inStr, uint32_t count, uint32_t *_retval)
+{
+ return WriteSegments(nsReadFromInputStream, inStr, count, _retval);
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::WriteSegments(nsReadSegmentFun reader, void * closure, uint32_t count, uint32_t *_retval)
+{
+ *_retval = 0;
+ nsresult rv;
+ while (count > 0) {
+ uint32_t left = std::min(count, mBufferSize - mCursor);
+ if (left == 0) {
+ rv = Flush();
+ if (NS_FAILED(rv))
+ return (*_retval > 0) ? NS_OK : rv;
+
+ continue;
+ }
+
+ uint32_t read = 0;
+ rv = reader(this, closure, mBuffer + mCursor, *_retval, left, &read);
+
+ if (NS_FAILED(rv)) // If we have written some data, return ok
+ return (*_retval > 0) ? NS_OK : rv;
+ mCursor += read;
+ *_retval += read;
+ count -= read;
+ mFillPoint = std::max(mFillPoint, mCursor);
+ }
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::IsNonBlocking(bool *aNonBlocking)
+{
+ if (mStream)
+ return Sink()->IsNonBlocking(aNonBlocking);
+ return NS_ERROR_NOT_INITIALIZED;
+}
+
+NS_IMETHODIMP_(char*)
+nsBufferedOutputStream::GetBuffer(uint32_t aLength, uint32_t aAlignMask)
+{
+ NS_ASSERTION(mGetBufferCount == 0, "nested GetBuffer!");
+ if (mGetBufferCount != 0)
+ return nullptr;
+
+ if (mBufferDisabled)
+ return nullptr;
+
+ char* buf = mBuffer + mCursor;
+ uint32_t rem = mBufferSize - mCursor;
+ if (rem == 0) {
+ if (NS_FAILED(Flush()))
+ return nullptr;
+ buf = mBuffer + mCursor;
+ rem = mBufferSize - mCursor;
+ }
+
+ uint32_t mod = (NS_PTR_TO_INT32(buf) & aAlignMask);
+ if (mod) {
+ uint32_t pad = aAlignMask + 1 - mod;
+ if (pad > rem)
+ return nullptr;
+
+ memset(buf, 0, pad);
+ mCursor += pad;
+ buf += pad;
+ rem -= pad;
+ }
+
+ if (aLength > rem)
+ return nullptr;
+ mGetBufferCount++;
+ return buf;
+}
+
+NS_IMETHODIMP_(void)
+nsBufferedOutputStream::PutBuffer(char* aBuffer, uint32_t aLength)
+{
+ NS_ASSERTION(mGetBufferCount == 1, "stray PutBuffer!");
+ if (--mGetBufferCount != 0)
+ return;
+
+ NS_ASSERTION(mCursor + aLength <= mBufferSize, "PutBuffer botch");
+ mCursor += aLength;
+ if (mFillPoint < mCursor)
+ mFillPoint = mCursor;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::DisableBuffering()
+{
+ NS_ASSERTION(!mBufferDisabled, "redundant call to DisableBuffering!");
+ NS_ASSERTION(mGetBufferCount == 0,
+ "DisableBuffer call between GetBuffer and PutBuffer!");
+ if (mGetBufferCount != 0)
+ return NS_ERROR_UNEXPECTED;
+
+ // Empty the buffer so nsBufferedStream::Tell works.
+ nsresult rv = Flush();
+ if (NS_FAILED(rv))
+ return rv;
+
+ mBufferDisabled = true;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::EnableBuffering()
+{
+ NS_ASSERTION(mBufferDisabled, "gratuitous call to EnableBuffering!");
+ mBufferDisabled = false;
+ return NS_OK;
+}
+
+NS_IMETHODIMP
+nsBufferedOutputStream::GetUnbufferedStream(nsISupports* *aStream)
+{
+ // Empty the buffer so subsequent i/o trumps any buffered data.
+ if (mFillPoint) {
+ nsresult rv = Flush();
+ if (NS_FAILED(rv))
+ return rv;
+ }
+
+ *aStream = mStream;
+ NS_IF_ADDREF(*aStream);
+ return NS_OK;
+}
+
+#undef METER
+
+////////////////////////////////////////////////////////////////////////////////