Add support for response filtering (issue #515).

- Add a new CefRequestHandler::GetResourceResponseFilter method and
  CefResponseFilter class.

include/capi/cef_request_handler_capi.h

@@ -45,6 +45,7 @@
 #include "include/capi/cef_request_capi.h"
 #include "include/capi/cef_resource_handler_capi.h"
 #include "include/capi/cef_response_capi.h"
+#include "include/capi/cef_response_filter_capi.h"
 #include "include/capi/cef_ssl_info_capi.h"
 
 #ifdef __cplusplus
@@ -162,6 +163,16 @@ typedef struct _cef_request_handler_t {
       struct _cef_browser_t* browser, struct _cef_frame_t* frame,
       struct _cef_request_t* request, struct _cef_response_t* response);
 
+  ///
+  // Called on the IO thread to optionally filter resource response content.
+  // |request| and |response| represent the request and response respectively
+  // and cannot be modified in this callback.
+  ///
+  struct _cef_response_filter_t* (CEF_CALLBACK *get_resource_response_filter)(
+      struct _cef_request_handler_t* self, struct _cef_browser_t* browser,
+      struct _cef_frame_t* frame, struct _cef_request_t* request,
+      struct _cef_response_t* response);
+
   ///
   // Called on the IO thread when a resource load has completed. |request| and
   // |response| represent the request and response respectively and cannot be

include/capi/cef_response_filter_capi.h

@@ -0,0 +1,91 @@
+// Copyright (c) 2015 Marshall A. Greenblatt. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the name Chromium Embedded
+// Framework nor the names of its contributors may be used to endorse
+// or promote products derived from this software without specific prior
+// written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// ---------------------------------------------------------------------------
+//
+// This file was generated by the CEF translator tool and should not edited
+// by hand. See the translator.README.txt file in the tools directory for
+// more information.
+//
+
+#ifndef CEF_INCLUDE_CAPI_CEF_RESPONSE_FILTER_CAPI_H_
+#define CEF_INCLUDE_CAPI_CEF_RESPONSE_FILTER_CAPI_H_
+#pragma once
+
+#include "include/capi/cef_base_capi.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+///
+// Implement this structure to filter resource response content. The functions
+// of this structure will be called on the browser process IO thread.
+///
+typedef struct _cef_response_filter_t {
+  ///
+  // Base structure.
+  ///
+  cef_base_t base;
+
+  ///
+  // Initialize the response filter. Will only be called a single time. The
+  // filter will not be installed if this function returns false (0).
+  ///
+  int (CEF_CALLBACK *init_filter)(struct _cef_response_filter_t* self);
+
+  // Called to filter a chunk of data. |data_in| is the input buffer containing
+  // |data_in_size| bytes of pre-filter data (|data_in| will be NULL if
+  // |data_in_size| is zero). |data_out| is the output buffer that can accept up
+  // to |data_out_size| bytes of filtered output data. Set |data_in_read| to the
+  // number of bytes that were read from |data_in|. Set |data_out_written| to
+  // the number of bytes that were written into |data_out|. If some or all of
+  // the pre-filter data was read successfully but more data is needed in order
+  // to continue filtering (filtered output is pending) return
+  // RESPONSE_FILTER_NEED_MORE_DATA. If some or all of the pre-filter data was
+  // read successfully and all available filtered output has been written return
+  // RESPONSE_FILTER_DONE. If an error occurs during filtering return
+  // RESPONSE_FILTER_ERROR. This function will be called repeatedly until there
+  // is no more data to filter (resource response is complete), |data_in_read|
+  // matches |data_in_size| (all available pre-filter bytes have been read), and
+  // the function returns RESPONSE_FILTER_DONE or RESPONSE_FILTER_ERROR. Do not
+  // keep a reference to the buffers passed to this function.
+  cef_response_filter_status_t (CEF_CALLBACK *filter)(
+      struct _cef_response_filter_t* self, void* data_in, size_t data_in_size,
+      size_t* data_in_read, void* data_out, size_t data_out_size,
+      size_t* data_out_written);
+} cef_response_filter_t;
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // CEF_INCLUDE_CAPI_CEF_RESPONSE_FILTER_CAPI_H_

include/cef_request_handler.h

@@ -44,6 +44,7 @@
 #include "include/cef_frame.h"
 #include "include/cef_resource_handler.h"
 #include "include/cef_response.h"
+#include "include/cef_response_filter.h"
 #include "include/cef_request.h"
 #include "include/cef_ssl_info.h"
 
@@ -181,6 +182,20 @@ class CefRequestHandler : public virtual CefBase {
     return false;
   }
 
+  ///
+  // Called on the IO thread to optionally filter resource response content.
+  // |request| and |response| represent the request and response respectively
+  // and cannot be modified in this callback.
+  ///
+  /*--cef()--*/
+  virtual CefRefPtr<CefResponseFilter> GetResourceResponseFilter(
+      CefRefPtr<CefBrowser> browser,
+      CefRefPtr<CefFrame> frame,
+      CefRefPtr<CefRequest> request,
+      CefRefPtr<CefResponse> response) {
+    return NULL;
+  }
+
   ///
   // Called on the IO thread when a resource load has completed. |request| and
   // |response| represent the request and response respectively and cannot be

include/cef_response_filter.h

@@ -0,0 +1,84 @@
+// Copyright (c) 2015 Marshall A. Greenblatt. All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//    * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//    * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//    * Neither the name of Google Inc. nor the name Chromium Embedded
+// Framework nor the names of its contributors may be used to endorse
+// or promote products derived from this software without specific prior
+// written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// ---------------------------------------------------------------------------
+//
+// The contents of this file must follow a specific format in order to
+// support the CEF translator tool. See the translator.README.txt file in the
+// tools directory for more information.
+//
+
+#ifndef CEF_INCLUDE_CEF_RESPONSE_FILTER_H_
+#define CEF_INCLUDE_CEF_RESPONSE_FILTER_H_
+#pragma once
+
+#include "include/cef_base.h"
+
+///
+// Implement this interface to filter resource response content. The methods of
+// this class will be called on the browser process IO thread.
+///
+/*--cef(source=client)--*/
+class CefResponseFilter : public virtual CefBase {
+ public:
+  typedef cef_response_filter_status_t FilterStatus;
+
+  ///
+  // Initialize the response filter. Will only be called a single time. The
+  // filter will not be installed if this method returns false.
+  ///
+  /*--cef()--*/
+  virtual bool InitFilter() =0;
+
+  // Called to filter a chunk of data. |data_in| is the input buffer containing
+  // |data_in_size| bytes of pre-filter data (|data_in| will be NULL if
+  // |data_in_size| is zero). |data_out| is the output buffer that can accept up
+  // to |data_out_size| bytes of filtered output data. Set |data_in_read| to the
+  // number of bytes that were read from |data_in|. Set |data_out_written| to
+  // the number of bytes that were written into |data_out|. If some or all of
+  // the pre-filter data was read successfully but more data is needed in order
+  // to continue filtering (filtered output is pending) return
+  // RESPONSE_FILTER_NEED_MORE_DATA. If some or all of the pre-filter data was
+  // read successfully and all available filtered output has been written return
+  // RESPONSE_FILTER_DONE. If an error occurs during filtering return
+  // RESPONSE_FILTER_ERROR. This method will be called repeatedly until there is
+  // no more data to filter (resource response is complete), |data_in_read|
+  // matches |data_in_size| (all available pre-filter bytes have been read), and
+  // the method returns RESPONSE_FILTER_DONE or RESPONSE_FILTER_ERROR. Do not
+  // keep a reference to the buffers passed to this method.
+  /*--cef(optional_param=data_in,default_retval=RESPONSE_FILTER_ERROR)--*/
+  virtual FilterStatus Filter(void* data_in,
+                              size_t data_in_size,
+                              size_t& data_in_read,
+                              void* data_out,
+                              size_t data_out_size,
+                              size_t& data_out_written) =0;
+};
+
+#endif  // CEF_INCLUDE_CEF_RESPONSE_FILTER_H_

include/internal/cef_types.h

@@ -2304,7 +2304,7 @@ typedef enum {
 // If the `--no-referrers` command-line flag is specified then the policy value
 // will be ignored and the Referrer value will never be sent.
 ///
-typedef enum  {
+typedef enum {
   ///
   // Always send the complete Referrer value.
   ///
@@ -2341,6 +2341,28 @@ typedef enum  {
   REFERRER_POLICY_ORIGIN_WHEN_CROSS_ORIGIN,
 } cef_referrer_policy_t;
 
+///
+// Return values for CefResponseFilter::Filter().
+///
+typedef enum {
+  ///
+  // Some or all of the pre-filter data was read successfully but more data is
+  // needed in order to continue filtering (filtered output is pending).
+  ///
+  RESPONSE_FILTER_NEED_MORE_DATA,
+
+  ///
+  // Some or all of the pre-filter data was read successfully and all available
+  // filtered output has been written.
+  ///
+  RESPONSE_FILTER_DONE,
+
+  ///
+  // An error occurred during filtering.
+  ///
+  RESPONSE_FILTER_ERROR
+} cef_response_filter_status_t;
+
 #ifdef __cplusplus
 }
 #endif