1 files changed, 123 insertions, 0 deletions
diff --git a/netwerk/protocol/res/PageThumbProtocolHandler.h b/netwerk/protocol/res/PageThumbProtocolHandler.h
new file mode 100644
index 0000000000..8c5c90acff
--- /dev/null
+++ b/netwerk/protocol/res/PageThumbProtocolHandler.h
@@ -0,0 +1,123 @@
+/* -*- 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/. */
+
+#ifndef PageThumbProtocolHandler_h___
+#define PageThumbProtocolHandler_h___
+
+#include "mozilla/Result.h"
+#include "SubstitutingProtocolHandler.h"
+
+namespace mozilla {
+namespace net {
+
+using PageThumbStreamPromise =
+    mozilla::MozPromise<nsCOMPtr<nsIInputStream>, nsresult, false>;
+
+class PageThumbStreamGetter;
+
+class PageThumbProtocolHandler final
+    : public nsISubstitutingProtocolHandler,
+      public nsIProtocolHandlerWithDynamicFlags,
+      public SubstitutingProtocolHandler,
+      public nsSupportsWeakReference {
+ public:
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIPROTOCOLHANDLERWITHDYNAMICFLAGS
+  NS_FORWARD_NSIPROTOCOLHANDLER(SubstitutingProtocolHandler::)
+  NS_FORWARD_NSISUBSTITUTINGPROTOCOLHANDLER(SubstitutingProtocolHandler::)
+
+  static already_AddRefed<PageThumbProtocolHandler> GetSingleton();
+
+  /**
+   * To be called in the parent process to obtain an input stream for the
+   * given thumbnail.
+   *
+   * @param aChildURI a moz-page-thumb URI sent from the child.
+   * @param aTerminateSender out param set to true when the params are invalid
+   *        and indicate the child should be terminated. If |aChildURI| is
+   *        not a moz-page-thumb URI, the child is in an invalid state and
+   *        should be terminated. This outparam will be set synchronously.
+   *
+   * @return PageThumbStreamPromise
+   *        The PageThumbStreamPromise will resolve with an nsIInputStream on
+   *        success, and reject with an nsresult on failure.
+   */
+  RefPtr<PageThumbStreamPromise> NewStream(nsIURI* aChildURI,
+                                           bool* aTerminateSender);
+
+ protected:
+  ~PageThumbProtocolHandler() = default;
+
+ private:
+  explicit PageThumbProtocolHandler();
+
+  [[nodiscard]] bool ResolveSpecialCases(const nsACString& aHost,
+                                         const nsACString& aPath,
+                                         const nsACString& aPathname,
+                                         nsACString& aResult) override;
+
+  /**
+   * On entry to this function, *aRetVal is expected to be non-null and already
+   * addrefed. This function may release the object stored in *aRetVal on entry
+   * and write a new pointer to an already addrefed channel to *aRetVal.
+   *
+   * @param aURI the moz-page-thumb URI.
+   * @param aLoadInfo the loadinfo for the request.
+   * @param aRetVal in/out channel param referring to the channel that
+   *        might need to be substituted with a remote channel.
+   * @return NS_OK if channel has been substituted successfully or no
+   *         substitution at all. Otherwise, returns an error. This function
+   *         will return NS_ERROR_NO_INTERFACE if the URI resolves to a
+   *         non file:// URI.
+   */
+  [[nodiscard]] virtual nsresult SubstituteChannel(
+      nsIURI* aURI, nsILoadInfo* aLoadInfo, nsIChannel** aRetVal) override;
+
+  /**
+   * This replaces the provided channel with a channel that will proxy the load
+   * to the parent process.
+   *
+   * @param aURI the moz-page-thumb URI.
+   * @param aLoadInfo the loadinfo for the request.
+   * @param aRetVal in/out channel param referring to the channel that
+   *        might need to be substituted with a remote channel.
+   * @return NS_OK if the replacement channel was created successfully.
+   *         Otherwise, returns an error.
+   */
+  Result<Ok, nsresult> SubstituteRemoteChannel(nsIURI* aURI,
+                                               nsILoadInfo* aLoadInfo,
+                                               nsIChannel** aRetVal);
+
+  /*
+   * Extracts the URL from the query string in the given moz-page-thumb URI
+   * and queries PageThumbsStorageService using the extracted URL to obtain
+   * the local file path of the screenshot. This should only be called from
+   * the parent because PageThumbsStorageService relies on the path of the
+   * profile directory, which is unavailable in the child.
+   *
+   * @param aPath the path of the moz-page-thumb URI.
+   * @param aThumbnailPath in/out string param referring to the thumbnail path.
+   * @return NS_OK if the thumbnail path was obtained successfully. Otherwise
+   *         returns an error.
+   */
+  nsresult GetThumbnailPath(const nsACString& aPath, nsString& aThumbnailPath);
+
+  // To allow parent IPDL actors to invoke methods on this handler when
+  // handling moz-page-thumb requests from the child.
+  static StaticRefPtr<PageThumbProtocolHandler> sSingleton;
+
+  // Set the channel's content type using the provided URI's type.
+  static void SetContentType(nsIURI* aURI, nsIChannel* aChannel);
+
+  // Gets a SimpleChannel that wraps the provided channel.
+  static void NewSimpleChannel(nsIURI* aURI, nsILoadInfo* aLoadinfo,
+                               PageThumbStreamGetter* aStreamGetter,
+                               nsIChannel** aRetVal);
+};
+
+}  // namespace net
+}  // namespace mozilla
+
+#endif /* PageThumbProtocolHandler_h___ */