text: // Copyright 2014 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "net/filter/filter.h"
  
  #include <utility>
  
  #include "base/macros.h"
  #include "net/base/io_buffer.h"
  #include "net/filter/mock_filter_context.h"
  #include "testing/gtest/include/gtest/gtest.h"
  
  namespace net {
  
  namespace {
  
  class PassThroughFilter : public Filter {
   public:
    PassThroughFilter() : Filter(FILTER_TYPE_UNSUPPORTED) {}
  
    FilterStatus ReadFilteredData(char* dest_buffer, int* dest_len) override {
      return CopyOut(dest_buffer, dest_len);
    }
  
    DISALLOW_COPY_AND_ASSIGN(PassThroughFilter);
  };
  
  }  // namespace
  
  TEST(FilterTest, ContentTypeId) {
    // Check for basic translation of Content-Encoding, including case variations.
    EXPECT_EQ(Filter::FILTER_TYPE_DEFLATE,
              Filter::ConvertEncodingToType("deflate"));
    EXPECT_EQ(Filter::FILTER_TYPE_DEFLATE,
              Filter::ConvertEncodingToType("deflAte"));
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP,
              Filter::ConvertEncodingToType("gzip"));
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP,
              Filter::ConvertEncodingToType("GzIp"));
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP,
              Filter::ConvertEncodingToType("x-gzip"));
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP,
              Filter::ConvertEncodingToType("X-GzIp"));
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH,
              Filter::ConvertEncodingToType("sdch"));
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH,
              Filter::ConvertEncodingToType("sDcH"));
    EXPECT_EQ(Filter::FILTER_TYPE_UNSUPPORTED,
              Filter::ConvertEncodingToType("weird"));
    EXPECT_EQ(Filter::FILTER_TYPE_UNSUPPORTED,
              Filter::ConvertEncodingToType("strange"));
  }
  
  TEST(FilterTest, SdchEncoding) {
    // Handle content encodings including SDCH.
    const std::string kTextHtmlMime("text/html");
    MockFilterContext filter_context;
    // Empty handle indicates to filter that SDCH is active.
    filter_context.SetSdchResponse(
        SdchManager::CreateEmptyDictionarySetForTesting());
  
    std::vector<Filter::FilterType> encoding_types;
  
    // Check for most common encoding, and verify it survives unchanged.
    encoding_types.clear();
    encoding_types.push_back(Filter::FILTER_TYPE_SDCH);
    encoding_types.push_back(Filter::FILTER_TYPE_GZIP);
    filter_context.SetMimeType(kTextHtmlMime);
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP, encoding_types[1]);
  
    // Unchanged even with other mime types.
    encoding_types.clear();
    encoding_types.push_back(Filter::FILTER_TYPE_SDCH);
    encoding_types.push_back(Filter::FILTER_TYPE_GZIP);
    filter_context.SetMimeType("other/type");
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP, encoding_types[1]);
  
    // Solo SDCH is extended to include optional gunzip.
    encoding_types.clear();
    encoding_types.push_back(Filter::FILTER_TYPE_SDCH);
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP_HELPING_SDCH, encoding_types[1]);
  }
  
  TEST(FilterTest, MissingSdchEncoding) {
    // Handle interesting case where entire SDCH encoding assertion "got lost."
    const std::string kTextHtmlMime("text/html");
    MockFilterContext filter_context;
    filter_context.SetSdchResponse(
        SdchManager::CreateEmptyDictionarySetForTesting());
  
    std::vector<Filter::FilterType> encoding_types;
  
    // Loss of encoding, but it was an SDCH response with html type.
    encoding_types.clear();
    filter_context.SetMimeType(kTextHtmlMime);
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH_POSSIBLE, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP_HELPING_SDCH, encoding_types[1]);
  
    // Loss of encoding, but it was an SDCH response with a prefix that says it
    // was an html type. Note that it *should* be the case that a precise match
    // with "text/html" we be collected by GetMimeType() and passed in, but we
    // coded the fixup defensively (scanning for a prefix of "text/html", so this
    // is an example which could survive such confusion in the caller).
    encoding_types.clear();
    filter_context.SetMimeType("text/html; charset=UTF-8");
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH_POSSIBLE, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP_HELPING_SDCH, encoding_types[1]);
  
    // No encoding, but it was an SDCH response with non-html type.
    encoding_types.clear();
    filter_context.SetMimeType("other/mime");
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(2U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_SDCH_POSSIBLE, encoding_types[0]);
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP_HELPING_SDCH, encoding_types[1]);
  }
  
  // FixupEncodingTypes() should leave gzip encoding intact.
  TEST(FilterTest, Gzip) {
    const std::string kUrl("http://example.com/foo");
    MockFilterContext filter_context;
    std::vector<Filter::FilterType> encoding_types;
    filter_context.SetURL(GURL(kUrl));
  
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    EXPECT_EQ(0U, encoding_types.size());
  
    encoding_types.clear();
    encoding_types.push_back(Filter::FILTER_TYPE_GZIP);
    Filter::FixupEncodingTypes(filter_context, &encoding_types);
    ASSERT_EQ(1U, encoding_types.size());
    EXPECT_EQ(Filter::FILTER_TYPE_GZIP, encoding_types.front());
  }
  
  // Make sure a series of three pass-through filters copies the data cleanly.
  // Regression test for http://crbug.com/418975.
  TEST(FilterTest, ThreeFilterChain) {
    std::unique_ptr<PassThroughFilter> filter1(new PassThroughFilter);
    std::unique_ptr<PassThroughFilter> filter2(new PassThroughFilter);
    std::unique_ptr<PassThroughFilter> filter3(new PassThroughFilter);
  
    filter1->InitBuffer(32 * 1024);
    filter2->InitBuffer(32 * 1024);
    filter3->InitBuffer(32 * 1024);
  
    filter2->next_filter_ = std::move(filter3);
    filter1->next_filter_ = std::move(filter2);
  
    // Initialize the input array with a varying byte sequence.
    const size_t input_array_size = 64 * 1024;
    char input_array[input_array_size];
    size_t read_array_index = 0;
    for (size_t i = 0; i < input_array_size; i++) {
      input_array[i] = i % 113;
    }
  
    const size_t output_array_size = 4 * 1024;
    char output_array[output_array_size];
  
    size_t compare_array_index = 0;
  
    do {
      // Read data from the filter chain.
      int amount_read = output_array_size;
      Filter::FilterStatus status = filter1->ReadData(output_array, &amount_read);
      EXPECT_NE(Filter::FILTER_ERROR, status);
      EXPECT_EQ(0, memcmp(output_array, input_array + compare_array_index,
                          amount_read));
      compare_array_index += amount_read;
  
      // Detect the various indications that data transfer along the chain is
      // complete.
      if (Filter::FILTER_DONE == status || Filter::FILTER_ERROR == status ||
          (Filter::FILTER_OK == status && amount_read == 0) ||
          (Filter::FILTER_NEED_MORE_DATA == status &&
           read_array_index == input_array_size))
        break;
  
      if (Filter::FILTER_OK == status)
        continue;
  
      // Write needed data into the filter chain.
      ASSERT_EQ(Filter::FILTER_NEED_MORE_DATA, status);
      ASSERT_NE(0, filter1->stream_buffer_size());
      size_t amount_to_copy = std::min(
          static_cast<size_t>(filter1->stream_buffer_size()),
          input_array_size - read_array_index);
      memcpy(filter1->stream_buffer()->data(),
             input_array + read_array_index,
             amount_to_copy);
      filter1->FlushStreamBuffer(amount_to_copy);
      read_array_index += amount_to_copy;
    } while (true);
  
    EXPECT_EQ(read_array_index, input_array_size);
    EXPECT_EQ(compare_array_index, input_array_size);
  }
  
  }  // Namespace net
  