import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

netwerk/base/nsIncrementalStreamLoader.cpp

@@ -0,0 +1,214 @@
+/* -*- 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/. */
+
+#include "nsIncrementalStreamLoader.h"
+#include "nsIInputStream.h"
+#include "nsIChannel.h"
+#include "nsError.h"
+#include "GeckoProfiler.h"
+
+#include <limits>
+
+nsIncrementalStreamLoader::nsIncrementalStreamLoader()
+  : mData(), mBytesConsumed(0)
+{
+}
+
+nsIncrementalStreamLoader::~nsIncrementalStreamLoader()
+{
+}
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::Init(nsIIncrementalStreamLoaderObserver* observer)
+{
+  NS_ENSURE_ARG_POINTER(observer);
+  mObserver = observer;
+  return NS_OK;
+}
+
+nsresult
+nsIncrementalStreamLoader::Create(nsISupports *aOuter, REFNSIID aIID, void **aResult)
+{
+  if (aOuter) return NS_ERROR_NO_AGGREGATION;
+
+  nsIncrementalStreamLoader* it = new nsIncrementalStreamLoader();
+  if (it == nullptr)
+    return NS_ERROR_OUT_OF_MEMORY;
+  NS_ADDREF(it);
+  nsresult rv = it->QueryInterface(aIID, aResult);
+  NS_RELEASE(it);
+  return rv;
+}
+
+NS_IMPL_ISUPPORTS(nsIncrementalStreamLoader, nsIIncrementalStreamLoader,
+                  nsIRequestObserver, nsIStreamListener,
+                  nsIThreadRetargetableStreamListener)
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::GetNumBytesRead(uint32_t* aNumBytes)
+{
+  *aNumBytes = mBytesConsumed + mData.length();
+  return NS_OK;
+}
+
+/* readonly attribute nsIRequest request; */
+NS_IMETHODIMP
+nsIncrementalStreamLoader::GetRequest(nsIRequest **aRequest)
+{
+  NS_IF_ADDREF(*aRequest = mRequest);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::OnStartRequest(nsIRequest* request, nsISupports *ctxt)
+{
+  nsCOMPtr<nsIChannel> chan( do_QueryInterface(request) );
+  if (chan) {
+    int64_t contentLength = -1;
+    chan->GetContentLength(&contentLength);
+    if (contentLength >= 0) {
+      if (uint64_t(contentLength) > std::numeric_limits<size_t>::max()) {
+        // Too big to fit into size_t, so let's bail.
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+      // preallocate buffer
+      if (!mData.initCapacity(contentLength)) {
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+    }
+  }
+  mContext = ctxt;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::OnStopRequest(nsIRequest* request, nsISupports *ctxt,
+                                         nsresult aStatus)
+{
+  PROFILER_LABEL("nsIncrementalStreamLoader", "OnStopRequest",
+    js::ProfileEntry::Category::NETWORK);
+
+  if (mObserver) {
+    // provide nsIIncrementalStreamLoader::request during call to OnStreamComplete
+    mRequest = request;
+    size_t length = mData.length();
+    uint8_t* elems = mData.extractOrCopyRawBuffer();
+    nsresult rv = mObserver->OnStreamComplete(this, mContext, aStatus,
+                                              length, elems);
+    if (rv != NS_SUCCESS_ADOPTED_DATA) {
+      // The observer didn't take ownership of the extracted data buffer, so
+      // put it back into mData.
+      mData.replaceRawBuffer(elems, length);
+    }
+    // done.. cleanup
+    ReleaseData();
+    mRequest = nullptr;
+    mObserver = nullptr;
+    mContext = nullptr;
+  }
+  return NS_OK;
+}
+
+nsresult
+nsIncrementalStreamLoader::WriteSegmentFun(nsIInputStream *inStr,
+                                           void *closure,
+                                           const char *fromSegment,
+                                           uint32_t toOffset,
+                                           uint32_t count,
+                                           uint32_t *writeCount)
+{
+  nsIncrementalStreamLoader *self = (nsIncrementalStreamLoader *) closure;
+
+  const uint8_t *data = reinterpret_cast<const uint8_t *>(fromSegment);
+  uint32_t consumedCount = 0;
+  nsresult rv;
+  if (self->mData.empty()) {
+    // Shortcut when observer wants to keep the listener's buffer empty.
+    rv = self->mObserver->OnIncrementalData(self, self->mContext,
+                                            count, data, &consumedCount);
+
+    if (rv != NS_OK) {
+      return rv;
+    }
+
+    if (consumedCount > count) {
+      return NS_ERROR_INVALID_ARG;
+    }
+
+    if (consumedCount < count) {
+      if (!self->mData.append(fromSegment + consumedCount,
+                              count - consumedCount)) {
+        self->mData.clearAndFree();
+        return NS_ERROR_OUT_OF_MEMORY;
+      }
+    }
+  } else {
+    // We have some non-consumed data from previous OnIncrementalData call,
+    // appending new data and reporting combined data.
+    if (!self->mData.append(fromSegment, count)) {
+      self->mData.clearAndFree();
+      return NS_ERROR_OUT_OF_MEMORY;
+    }
+    size_t length = self->mData.length();
+    uint32_t reportCount = length > UINT32_MAX ? UINT32_MAX : (uint32_t)length;
+    uint8_t* elems = self->mData.extractOrCopyRawBuffer();
+
+    rv = self->mObserver->OnIncrementalData(self, self->mContext,
+                                            reportCount, elems, &consumedCount);
+
+    // We still own elems, freeing its memory when exiting scope.
+    if (rv != NS_OK) {
+      free(elems);
+      return rv;
+    }
+
+    if (consumedCount > reportCount) {
+      free(elems);
+      return NS_ERROR_INVALID_ARG;
+    }
+
+    if (consumedCount == length) {
+      free(elems); // good case -- fully consumed data
+    } else {
+      // Adopting elems back (at least its portion).
+      self->mData.replaceRawBuffer(elems, length);
+      if (consumedCount > 0) {
+        self->mData.erase(self->mData.begin() + consumedCount);
+      }
+    }
+  }
+
+  self->mBytesConsumed += consumedCount;
+  *writeCount = count;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::OnDataAvailable(nsIRequest* request, nsISupports *ctxt,
+                                nsIInputStream *inStr,
+                                uint64_t sourceOffset, uint32_t count)
+{
+  if (mObserver) {
+    // provide nsIIncrementalStreamLoader::request during call to OnStreamComplete
+    mRequest = request;
+  }
+  uint32_t countRead;
+  nsresult rv = inStr->ReadSegments(WriteSegmentFun, this, count, &countRead);
+  mRequest = nullptr;
+  return rv;
+}
+
+void
+nsIncrementalStreamLoader::ReleaseData()
+{
+  mData.clearAndFree();
+}
+
+NS_IMETHODIMP
+nsIncrementalStreamLoader::CheckListenerChain()
+{
+  return NS_OK;
+}