From 5f8de423f190bbb79a62f804151bc24824fa32d8 Mon Sep 17 00:00:00 2001 From: "Matt A. Tobin" Date: Fri, 2 Feb 2018 04:16:08 -0500 Subject: Add m-esr52 at 52.6.0 --- .../shared/heapsnapshot/ZeroCopyNSIOutputStream.h | 70 ++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 devtools/shared/heapsnapshot/ZeroCopyNSIOutputStream.h (limited to 'devtools/shared/heapsnapshot/ZeroCopyNSIOutputStream.h') diff --git a/devtools/shared/heapsnapshot/ZeroCopyNSIOutputStream.h b/devtools/shared/heapsnapshot/ZeroCopyNSIOutputStream.h new file mode 100644 index 000000000..117fc0f87 --- /dev/null +++ b/devtools/shared/heapsnapshot/ZeroCopyNSIOutputStream.h @@ -0,0 +1,70 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */ +/* 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/. */ + +#ifndef mozilla_devtools_ZeroCopyNSIOutputStream__ +#define mozilla_devtools_ZeroCopyNSIOutputStream__ + +#include +#include + +#include "nsCOMPtr.h" +#include "nsIOutputStream.h" + +namespace mozilla { +namespace devtools { + +// A `google::protobuf::io::ZeroCopyOutputStream` implementation that uses an +// `nsIOutputStream` under the covers. +// +// This class will automatically write and flush its data to the +// `nsIOutputStream` in its destructor, but if you care whether that call +// succeeds or fails, then you should call the `flush` method yourself. Errors +// will be logged, however. +class MOZ_STACK_CLASS ZeroCopyNSIOutputStream + : public ::google::protobuf::io::ZeroCopyOutputStream +{ + static const int BUFFER_SIZE = 8192; + + // The nsIOutputStream we are streaming to. + nsCOMPtr& out; + + // The buffer we write data to before passing it to the output stream. + char buffer[BUFFER_SIZE]; + + // The status of writing to the underlying output stream. + nsresult result_; + + // The number of bytes in the buffer that have been used thus far. + int amountUsed; + + // Excluding the amount of the buffer currently used (which hasn't been + // written and flushed yet), this is the number of bytes written to the output + // stream. + int64_t writtenCount; + + // Write the internal buffer to the output stream and flush it. + nsresult writeBuffer(); + +public: + explicit ZeroCopyNSIOutputStream(nsCOMPtr& out); + + nsresult flush() { return writeBuffer(); } + + // Return true if writing to the underlying output stream ever failed. + bool failed() const { return NS_FAILED(result_); } + + nsresult result() const { return result_; } + + // ZeroCopyOutputStream Interface + virtual ~ZeroCopyNSIOutputStream() override; + virtual bool Next(void** data, int* size) override; + virtual void BackUp(int count) override; + virtual ::google::protobuf::int64 ByteCount() const override; +}; + +} // namespace devtools +} // namespace mozilla + +#endif // mozilla_devtools_ZeroCopyNSIOutputStream__ -- cgit v1.2.3