gecko-dev/dom/webbrowserpersist/WebBrowserPersistSerializeChild.cpp

/* -*- Mode: C++; tab-width: 4; 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/. */

#include "WebBrowserPersistSerializeChild.h"

#include <algorithm>

#include "nsThreadUtils.h"

namespace mozilla {

NS_IMPL_ISUPPORTS(WebBrowserPersistSerializeChild,
                  nsIWebBrowserPersistWriteCompletion,
                  nsIWebBrowserPersistURIMap, nsIOutputStream)

WebBrowserPersistSerializeChild::WebBrowserPersistSerializeChild(
    const WebBrowserPersistURIMap& aMap)
    : mMap(aMap) {}

WebBrowserPersistSerializeChild::~WebBrowserPersistSerializeChild() = default;

NS_IMETHODIMP
WebBrowserPersistSerializeChild::OnFinish(
    nsIWebBrowserPersistDocument* aDocument, nsIOutputStream* aStream,
    const nsACString& aContentType, nsresult aStatus) {
  MOZ_ASSERT(aStream == this);
  nsCString contentType(aContentType);
  Send__delete__(this, contentType, aStatus);
  return NS_OK;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::GetNumMappedURIs(uint32_t* aNum) {
  *aNum = static_cast<uint32_t>(mMap.mapURIs().Length());
  return NS_OK;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::GetURIMapping(uint32_t aIndex,
                                               nsACString& aMapFrom,
                                               nsACString& aMapTo) {
  if (aIndex >= mMap.mapURIs().Length()) {
    return NS_ERROR_INVALID_ARG;
  }
  aMapFrom = mMap.mapURIs()[aIndex].mapFrom();
  aMapTo = mMap.mapURIs()[aIndex].mapTo();
  return NS_OK;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::GetTargetBaseURI(nsACString& aURI) {
  aURI = mMap.targetBaseURI();
  return NS_OK;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::Close() {
  NS_WARNING("WebBrowserPersistSerializeChild::Close()");
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::Flush() {
  NS_WARNING("WebBrowserPersistSerializeChild::Flush()");
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::Write(const char* aBuf, uint32_t aCount,
                                       uint32_t* aWritten) {
  // Normally an nsIOutputStream would have to be thread-safe, but
  // nsDocumentEncoder currently doesn't call this off the main
  // thread (which also means it's difficult to test the
  // thread-safety code this class doesn't yet have).
  //
  // This is *not* an NS_ERROR_NOT_IMPLEMENTED, because at this
  // point we've probably already misused the non-thread-safe
  // refcounting.
  MOZ_RELEASE_ASSERT(NS_IsMainThread(), "Fix this class to be thread-safe.");

  // Limit the message size to 64k because large messages are
  // potentially bad for the latency of other messages on the same channel.
  static const uint32_t kMaxWrite = 65536;

  // Work around bug 1181433 by sending multiple messages if
  // necessary to write the entire aCount bytes, even though
  // nsIOutputStream.idl says we're allowed to do a short write.
  const char* buf = aBuf;
  uint32_t count = aCount;
  *aWritten = 0;
  while (count > 0) {
    uint32_t toWrite = std::min(kMaxWrite, count);
    nsTArray<uint8_t> arrayBuf;
    // It would be nice if this extra copy could be avoided.
    arrayBuf.AppendElements(buf, toWrite);
    SendWriteData(std::move(arrayBuf));
    *aWritten += toWrite;
    buf += toWrite;
    count -= toWrite;
  }
  return NS_OK;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::WriteFrom(nsIInputStream* aFrom,
                                           uint32_t aCount,
                                           uint32_t* aWritten) {
  NS_WARNING("WebBrowserPersistSerializeChild::WriteFrom()");
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::WriteSegments(nsReadSegmentFun aFun,
                                               void* aCtx, uint32_t aCount,
                                               uint32_t* aWritten) {
  NS_WARNING("WebBrowserPersistSerializeChild::WriteSegments()");
  return NS_ERROR_NOT_IMPLEMENTED;
}

NS_IMETHODIMP
WebBrowserPersistSerializeChild::IsNonBlocking(bool* aNonBlocking) {
  // Writes will never fail with NS_BASE_STREAM_WOULD_BLOCK, so:
  *aNonBlocking = false;
  return NS_OK;
}

}  // namespace mozilla