Add brotli content-encoding filter.

net/filter/filter.cc

Index: net/filter/filter.cc
diff --git a/net/filter/filter.cc b/net/filter/filter.cc
index f9c3712cf4ac1c788583f1731882709f90f8906b..13aa6df8974441d5c0469eed43aa8368846e3531 100644
--- a/net/filter/filter.cc
+++ b/net/filter/filter.cc
@@ -28,6 +28,9 @@
 #include "base/values.h"
 #include "net/base/io_buffer.h"
 #include "net/base/sdch_net_log_params.h"
+#if !defined(DISABLE_BROTLI_SUPPORT)
+#include "net/filter/brotli_filter.h"
+#endif
 #include "net/filter/gzip_filter.h"
 #include "net/filter/sdch_filter.h"
 #include "net/url_request/url_request_context.h"
@@ -38,6 +41,7 @@ namespace net {
 namespace {
 
 // Filter types (using canonical lower case only):
+const char kBrotli[]       = "br";

[Randy Smith (Not in Mondays), 2015/11/28 22:15:24]

I'd rather not use an abbreviation; can we say "brotili" instead?

[eustas, 2015/11/30 10:19:00]

This constant is used in ConvertEncodingToType used by
URLRequestHttpJob::SetupFilter
Brotli is associated with "br" in IANA (see section 12
https://datatracker.ietf.org/doc/draft-alakuijala-brotli/?include_text=1).
Firefox already supports "br" accept/content-encoding.

 const char kDeflate[]      = "deflate";
 const char kGZip[]         = "gzip";
 const char kXGZip[]        = "x-gzip";
@@ -62,6 +66,8 @@ void LogSdchProblem(const FilterContext& filter_context,
 
 std::string FilterTypeAsString(Filter::FilterType type_id) {
   switch (type_id) {
+    case Filter::FILTER_TYPE_BROTLI:
+      return "FILTER_TYPE_BROTLI";
     case Filter::FILTER_TYPE_DEFLATE:
       return "FILTER_TYPE_DEFLATE";
     case Filter::FILTER_TYPE_GZIP:
@@ -184,7 +190,9 @@ bool Filter::FlushStreamBuffer(int stream_data_len) {
 Filter::FilterType Filter::ConvertEncodingToType(
     const std::string& filter_type) {
   FilterType type_id;
-  if (base::LowerCaseEqualsASCII(filter_type, kDeflate)) {
+  if (base::LowerCaseEqualsASCII(filter_type, kBrotli)) {
+    type_id = FILTER_TYPE_BROTLI;
+  } else if (base::LowerCaseEqualsASCII(filter_type, kDeflate)) {
     type_id = FILTER_TYPE_DEFLATE;
   } else if (base::LowerCaseEqualsASCII(filter_type, kGZip) ||
              base::LowerCaseEqualsASCII(filter_type, kXGZip)) {
@@ -350,6 +358,17 @@ Filter::FilterStatus Filter::CopyOut(char* dest_buffer, int* dest_len) {
 }
 
 // static
+Filter* Filter::InitBrotliFilter(FilterType type_id, int buffer_size) {
+#if !defined(DISABLE_BROTLI_SUPPORT)
+  scoped_ptr<BrotliFilter> brotli_filter(new BrotliFilter(type_id));
+  brotli_filter->InitBuffer(buffer_size);
+  return brotli_filter->InitDecoding() ? brotli_filter.release() : NULL;
+#else
+  return NULL;
+#endif
+}
+
+// static
 Filter* Filter::InitGZipFilter(FilterType type_id, int buffer_size) {
   scoped_ptr<GZipFilter> gz_filter(new GZipFilter(type_id));
   gz_filter->InitBuffer(buffer_size);
@@ -372,6 +391,10 @@ Filter* Filter::PrependNewFilter(FilterType type_id,
                                  Filter* filter_list) {
   scoped_ptr<Filter> first_filter;  // Soon to be start of chain.
   switch (type_id) {
+    case FILTER_TYPE_BROTLI:
+      if (filter_context.IsBrotliEnabled())
+        first_filter.reset(InitBrotliFilter(type_id, buffer_size));
+      break;
     case FILTER_TYPE_GZIP_HELPING_SDCH:
     case FILTER_TYPE_DEFLATE:
     case FILTER_TYPE_GZIP: