Bug 1847358 part 2: create and use nsIBaseChannel to reduce code debt and better-encapsulate logic for range-requests on nsBaseChannel classes; r=dlrobertson,necko-reviewers,jesup

Differential Revision: https://phabricator.services.mozilla.com/D203379

dom/fetch/FetchDriver.cpp

@@ -13,6 +13,7 @@
 #include "mozilla/dom/ReferrerInfo.h"
 #include "nsIAsyncVerifyRedirectCallback.h"
 #include "mozilla/dom/Document.h"
+#include "nsIBaseChannel.h"
 #include "nsICookieJarSettings.h"
 #include "nsIFile.h"
 #include "nsIInputStream.h"
@@ -28,7 +29,6 @@
 #include "nsIPipe.h"
 #include "nsIRedirectHistoryEntry.h"
 
-#include "nsBaseChannel.h"
 #include "nsContentPolicyUtils.h"
 #include "nsDataChannel.h"
 #include "nsDataHandler.h"
@@ -1100,13 +1100,10 @@ FetchDriver::OnStartRequest(nsIRequest* aRequest) {
     // Should set a Content-Range header for blob scheme
     // (https://fetch.spec.whatwg.org/#scheme-fetch)
     nsAutoCString contentRange(VoidCString());
-    nsCOMPtr<nsIURI> uri;
-    channel->GetURI(getter_AddRefs(uri));
-    if (IsBlobURI(uri)) {
-      nsBaseChannel* bchan = static_cast<nsBaseChannel*>(channel.get());
-      MOZ_ASSERT(bchan);
-      Maybe<mozilla::net::ContentRange> range = bchan->GetContentRange();
-      if (range.isSome()) {
+    nsCOMPtr<nsIBaseChannel> baseChan = do_QueryInterface(mChannel);
+    if (baseChan) {
+      RefPtr<mozilla::net::ContentRange> range = baseChan->ContentRange();
+      if (range) {
         range->AsHeader(contentRange);
       }
     }
@@ -1122,6 +1119,8 @@ FetchDriver::OnStartRequest(nsIRequest* aRequest) {
       MOZ_ASSERT(!result.Failed());
     }
 
+    nsCOMPtr<nsIURI> uri;
+    channel->GetURI(getter_AddRefs(uri));
     if (uri && uri->SchemeIs("data")) {
       nsDataChannel* dchan = static_cast<nsDataChannel*>(channel.get());
       MOZ_ASSERT(dchan);

dom/file/uri/BlobURLInputStream.cpp

@@ -489,9 +489,9 @@ nsresult BlobURLInputStream::StoreBlobImplStream(
   // If a Range header was in the request then fetch/XHR will have set a
   // ContentRange on the channel earlier so we may slice the blob now.
   blobImpl->GetType(blobContentType);
-  const Maybe<mozilla::net::ContentRange>& contentRange =
-      mChannel->GetContentRange();
-  if (contentRange.isSome()) {
+  const RefPtr<mozilla::net::ContentRange>& contentRange =
+      mChannel->ContentRange();
+  if (contentRange) {
     IgnoredErrorResult result;
     uint64_t start = contentRange->Start();
     uint64_t end = contentRange->End();

dom/file/uri/BlobURLProtocolHandler.cpp

@@ -948,7 +948,7 @@ nsresult NS_GetBlobForBlobURISpec(const nsACString& aSpec,
 }
 
 // Blob requests may specify a range header. We parse, validate, and
-// store that info here, and save it on the nsBaseChannel, where it
+// store that info here, and save it on the nsIBaseChannel, where it
 // can be accessed by BlobURLInputStream::StoreBlobImplStream.
 nsresult NS_SetChannelContentRangeForBlobURI(nsIChannel* aChannel, nsIURI* aURI,
                                              nsACString& aRangeHeader) {
@@ -963,9 +963,8 @@ nsresult NS_SetChannelContentRangeForBlobURI(nsIChannel* aChannel, nsIURI* aURI,
   if (result.Failed()) {
     return NS_ERROR_NO_CONTENT;
   }
-  nsBaseChannel* bchan = static_cast<nsBaseChannel*>(aChannel);
-  MOZ_ASSERT(bchan);
-  if (!bchan->SetContentRange(aRangeHeader, size)) {
+  nsCOMPtr<nsIBaseChannel> baseChan = do_QueryInterface(aChannel);
+  if (!baseChan || !baseChan->SetContentRangeFromHeader(aRangeHeader, size)) {
     return NS_ERROR_NET_PARTIAL_TRANSFER;
   }
   return NS_OK;

dom/xhr/XMLHttpRequestMainThread.cpp

@@ -49,6 +49,7 @@
 #include "mozilla/StaticPrefs_privacy.h"
 #include "mozilla/dom/ProgressEvent.h"
 #include "nsDataChannel.h"
+#include "nsIBaseChannel.h"
 #include "nsIJARChannel.h"
 #include "nsIJARURI.h"
 #include "nsReadableUtils.h"
@@ -864,14 +865,28 @@ bool XMLHttpRequestMainThread::IsDeniedCrossSiteCORSRequest() {
   return false;
 }
 
-Maybe<mozilla::net::ContentRange>
+bool XMLHttpRequestMainThread::BadContentRangeRequested() {
+  if (!mChannel) {
+    return false;
+  }
+  // Only nsIBaseChannel supports this
+  nsCOMPtr<nsIBaseChannel> baseChan = do_QueryInterface(mChannel);
+  if (!baseChan) {
+    return false;
+  }
+  // A bad range was requested if the channel has no content range
+  // despite the request specifying a range header.
+  return !baseChan->ContentRange() && mAuthorRequestHeaders.Has("range");
+}
+
+RefPtr<mozilla::net::ContentRange>
 XMLHttpRequestMainThread::GetRequestedContentRange() const {
   MOZ_ASSERT(mChannel);
-  nsBaseChannel* baseChan = static_cast<nsBaseChannel*>(mChannel.get());
+  nsCOMPtr<nsIBaseChannel> baseChan = do_QueryInterface(mChannel);
   if (!baseChan) {
-    return mozilla::Nothing();
+    return nullptr;
   }
-  return baseChan->GetContentRange();
+  return baseChan->ContentRange();
 }
 
 void XMLHttpRequestMainThread::GetContentRangeHeader(nsACString& out) const {
@@ -879,8 +894,8 @@ void XMLHttpRequestMainThread::GetContentRangeHeader(nsACString& out) const {
     out.SetIsVoid(true);
     return;
   }
-  Maybe<mozilla::net::ContentRange> range = GetRequestedContentRange();
-  if (range.isSome()) {
+  RefPtr<mozilla::net::ContentRange> range = GetRequestedContentRange();
+  if (range) {
     range->AsHeader(out);
   } else {
     out.SetIsVoid(true);
@@ -944,8 +959,7 @@ uint32_t XMLHttpRequestMainThread::GetStatus(ErrorResult& aRv) {
   nsCOMPtr<nsIHttpChannel> httpChannel = GetCurrentHttpChannel();
   if (!httpChannel) {
     // Pretend like we got a 200/206 response, since our load was successful
-    return IsBlobURI(mRequestURL) && GetRequestedContentRange().isSome() ? 206
-                                                                         : 200;
+    return GetRequestedContentRange() ? 206 : 200;
   }
 
   uint32_t status;
@@ -1956,8 +1970,7 @@ XMLHttpRequestMainThread::OnStartRequest(nsIRequest* request) {
 
   // If we were asked for a bad range on a blob URL, but we're async,
   // we should throw now in order to fire an error progress event.
-  if (IsBlobURI(mRequestURL) && GetRequestedContentRange().isNothing() &&
-      mAuthorRequestHeaders.Has("range")) {
+  if (BadContentRangeRequested()) {
     return NS_ERROR_NET_PARTIAL_TRANSFER;
   }
 

dom/xhr/XMLHttpRequestMainThread.h

@@ -48,7 +48,6 @@
 #include "mozilla/dom/XMLHttpRequestEventTarget.h"
 #include "mozilla/dom/XMLHttpRequestString.h"
 #include "mozilla/Encoding.h"
-#include "nsBaseChannel.h"
 
 #ifdef Status
 /* Xlib headers insist on this for some reason... Nuke it because
@@ -65,6 +64,10 @@ class nsILoadGroup;
 namespace mozilla {
 class ProfileChunkedBuffer;
 
+namespace net {
+class ContentRange;
+}
+
 namespace dom {
 
 class DOMString;
@@ -507,7 +510,8 @@ class XMLHttpRequestMainThread final : public XMLHttpRequest,
 
   void AbortInternal(ErrorResult& aRv);
 
-  Maybe<mozilla::net::ContentRange> GetRequestedContentRange() const;
+  bool BadContentRangeRequested();
+  RefPtr<mozilla::net::ContentRange> GetRequestedContentRange() const;
   void GetContentRangeHeader(nsACString&) const;
 
   struct PendingEvent {

netwerk/base/ContentRange.h

@@ -21,6 +21,8 @@ namespace mozilla::net {
 
 class ContentRange {
  private:
+  ~ContentRange() = default;
+
   uint64_t mStart{0};
   uint64_t mEnd{0};
   uint64_t mSize{0};
@@ -34,6 +36,8 @@ class ContentRange {
       : mStart(aStart), mEnd(aEnd), mSize(aSize) {}
   ContentRange(const nsACString& aRangeHeader, uint64_t aSize);
   void AsHeader(nsACString& aOutString) const;
+
+  NS_INLINE_DECL_REFCOUNTING(ContentRange)
 };
 
 }  // namespace mozilla::net

netwerk/base/moz.build

@@ -18,6 +18,7 @@ XPIDL_SOURCES += [
     "nsIAuthPromptCallback.idl",
     "nsIAuthPromptProvider.idl",
     "nsIBackgroundFileSaver.idl",
+    "nsIBaseChannel.idl",
     "nsIBufferedStreams.idl",
     "nsIByteRangeRequest.idl",
     "nsICacheInfoChannel.idl",

netwerk/base/nsBaseChannel.cpp

@@ -8,7 +8,6 @@
 #include "nsContentUtils.h"
 #include "nsURLHelper.h"
 #include "nsNetCID.h"
-#include "nsMimeTypes.h"
 #include "nsUnknownDecoder.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsMimeTypes.h"
@@ -302,6 +301,7 @@ NS_IMPL_RELEASE(nsBaseChannel)
 NS_INTERFACE_MAP_BEGIN(nsBaseChannel)
   NS_INTERFACE_MAP_ENTRY(nsIRequest)
   NS_INTERFACE_MAP_ENTRY(nsIChannel)
+  NS_INTERFACE_MAP_ENTRY(nsIBaseChannel)
   NS_INTERFACE_MAP_ENTRY(nsIThreadRetargetableRequest)
   NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
   NS_INTERFACE_MAP_ENTRY(nsITransportEventSink)
@@ -966,3 +966,17 @@ NS_IMETHODIMP nsBaseChannel::GetCanceled(bool* aCanceled) {
 void nsBaseChannel::SetupNeckoTarget() {
   mNeckoTarget = GetMainThreadSerialEventTarget();
 }
+
+NS_IMETHODIMP nsBaseChannel::GetContentRange(
+    RefPtr<mozilla::net::ContentRange>* aRange) {
+  if (aRange) {
+    *aRange = mContentRange;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsBaseChannel::SetContentRange(
+    RefPtr<mozilla::net::ContentRange> aRange) {
+  mContentRange = aRange;
+  return NS_OK;
+}

netwerk/base/nsBaseChannel.h

@@ -14,6 +14,7 @@
 #include "mozilla/net/PrivateBrowsingChannel.h"
 #include "nsHashPropertyBag.h"
 #include "nsIAsyncVerifyRedirectCallback.h"
+#include "nsIBaseChannel.h"
 #include "nsIChannel.h"
 #include "nsIInterfaceRequestor.h"
 #include "nsILoadGroup.h"
@@ -47,6 +48,7 @@ class nsICancelable;
 
 class nsBaseChannel
     : public nsHashPropertyBag,
+      public nsIBaseChannel,
       public nsIChannel,
       public nsIThreadRetargetableRequest,
       public nsIInterfaceRequestor,
@@ -59,6 +61,7 @@ class nsBaseChannel
   NS_DECL_ISUPPORTS_INHERITED
   NS_DECL_NSIREQUEST
   NS_DECL_NSICHANNEL
+  NS_DECL_NSIBASECHANNEL
   NS_DECL_NSIINTERFACEREQUESTOR
   NS_DECL_NSITRANSPORTEVENTSINK
   NS_DECL_NSIASYNCVERIFYREDIRECTCALLBACK
@@ -198,26 +201,6 @@ class nsBaseChannel
     return mPumpingData || mWaitingOnAsyncRedirect;
   }
 
-  // Blob requests may specify a range header. We must parse, validate, and
-  // store that info in a place where BlobURLInputStream::StoreBlobImplStream
-  // can access it.
-  const mozilla::Maybe<mozilla::net::ContentRange>& GetContentRange() const {
-    return mContentRange;
-  }
-
-  void SetContentRange(uint64_t aStart, uint64_t aEnd, uint64_t aSize) {
-    mContentRange.emplace(mozilla::net::ContentRange(aStart, aEnd, aSize));
-  }
-
-  bool SetContentRange(const nsACString& aRangeHeader, uint64_t aSize) {
-    auto range = mozilla::net::ContentRange(aRangeHeader, aSize);
-    if (!range.IsValid()) {
-      return false;
-    }
-    mContentRange.emplace(range);
-    return true;
-  }
-
   // Helper function for querying the channel's notification callbacks.
   template <class T>
   void GetCallback(nsCOMPtr<T>& result) {
@@ -308,7 +291,7 @@ class nsBaseChannel
   bool mWaitingOnAsyncRedirect{false};
   bool mOpenRedirectChannel{false};
   uint32_t mRedirectFlags{0};
-  mozilla::Maybe<mozilla::net::ContentRange> mContentRange;
+  RefPtr<mozilla::net::ContentRange> mContentRange;
 
  protected:
   nsCString mContentType;

netwerk/base/nsIBaseChannel.idl

@@ -0,0 +1,48 @@
+/* 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 "nsISupports.idl"
+
+%{C++
+#include "mozilla/net/ContentRange.h"
+%}
+
+/**
+ * The nsIBaseChannel interface allows C++ code to query the interface
+ * of channels safely to gain access to content range functionality.
+ * This allows subclasses to optionally handle range-requests on their
+ * types using fetch/XMLHttpRequest even if they are not accessed via
+ * HTTP and therefore normally do not have support for headers.
+ */
+
+native ContentRangeRef(RefPtr<mozilla::net::ContentRange>);
+
+[uuid(036d5cd7-9a53-40e3-9c72-c2ffaa15aa2b)]
+interface nsIBaseChannel : nsISupports {
+
+  /**
+   * Used by fetch and XMLHttpRequest to get only the range specified in the
+   * Range request header (if given) for the response body (e.g, for blob URLs)
+   */
+  attribute ContentRangeRef contentRange;
+
+%{C++
+  RefPtr<mozilla::net::ContentRange> ContentRange() {
+    RefPtr<mozilla::net::ContentRange> range;
+    mozilla::Unused << GetContentRange(&range);
+    return range;
+  }
+
+  bool SetContentRangeFromHeader(const nsACString& aHeader, uint64_t aSize) {
+    RefPtr<mozilla::net::ContentRange> range =
+      new mozilla::net::ContentRange(aHeader, aSize);
+    if (!range->IsValid()) {
+      return false;
+    }
+    SetContentRange(range);
+    return true;
+  }
+%}
+
+};