Remove net::Filter code

net/filter/filter.cc

Index: net/filter/filter.cc
diff --git a/net/filter/filter.cc b/net/filter/filter.cc
deleted file mode 100644
index 31a9d1a6fb4553f3541c3919de3d86933ff2ef99..0000000000000000000000000000000000000000
--- a/net/filter/filter.cc
+++ /dev/null
@@ -1,453 +0,0 @@
-// 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.
-
-// The basic usage of the Filter interface is described in the comment at
-// the beginning of filter.h. If Filter::Factory is passed a vector of
-// size greater than 1, that interface is implemented by a series of filters
-// connected in a chain. In such a case the first filter
-// in the chain proxies calls to ReadData() so that its return values
-// apply to the entire chain.
-//
-// In a filter chain, the data flows from first filter (held by the
-// caller) down the chain. When ReadData() is called on any filter
-// except for the last filter, it proxies the call down the chain,
-// filling in the input buffers of subsequent filters if needed (==
-// that filter's last_status() value is FILTER_NEED_MORE_DATA) and
-// available (== the current filter has data it can output). The last
-// Filter will then output data if possible, and return
-// FILTER_NEED_MORE_DATA if not. Because the indirection pushes
-// data along the filter chain at each level if it's available and the
-// next filter needs it, a return value of FILTER_NEED_MORE_DATA from the
-// final filter will apply to the entire chain.
-
-#include "net/filter/filter.h"
-
-#include "base/files/file_path.h"
-#include "base/strings/string_util.h"
-#include "base/values.h"
-#include "net/base/io_buffer.h"
-#include "net/base/sdch_net_log_params.h"
-#include "net/filter/brotli_filter.h"
-#include "net/filter/gzip_filter.h"
-#include "net/filter/sdch_filter.h"
-#include "net/log/net_log_event_type.h"
-#include "net/log/net_log_with_source.h"
-#include "net/url_request/url_request_context.h"
-#include "url/gurl.h"
-
-namespace net {
-
-namespace {
-
-// Filter types (using canonical lower case only):
-const char kBrotli[]       = "br";
-const char kDeflate[]      = "deflate";
-const char kGZip[]         = "gzip";
-const char kXGZip[]        = "x-gzip";
-const char kSdch[]         = "sdch";
-// compress and x-compress are currently not supported. If we decide to support
-// them, we'll need the same mime type compatibility hack we have for gzip. For
-// more information, see Firefox's nsHttpChannel::ProcessNormal.
-
-// Mime types:
-const char kTextHtml[]             = "text/html";
-
-// Buffer size allocated when de-compressing data.
-const int kFilterBufSize = 32 * 1024;
-
-void LogSdchProblem(const FilterContext& filter_context,
-                    SdchProblemCode problem) {
-  SdchManager::SdchErrorRecovery(problem);
-  filter_context.GetNetLog().AddEvent(
-      NetLogEventType::SDCH_DECODING_ERROR,
-      base::Bind(&NetLogSdchResourceProblemCallback, problem));
-}
-
-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:
-      return "FILTER_TYPE_GZIP";
-    case Filter::FILTER_TYPE_GZIP_HELPING_SDCH:
-      return "FILTER_TYPE_GZIP_HELPING_SDCH";
-    case Filter::FILTER_TYPE_SDCH:
-      return "FILTER_TYPE_SDCH";
-    case Filter::FILTER_TYPE_SDCH_POSSIBLE  :
-      return "FILTER_TYPE_SDCH_POSSIBLE  ";
-    case Filter::FILTER_TYPE_UNSUPPORTED:
-      return "FILTER_TYPE_UNSUPPORTED";
-    case Filter::FILTER_TYPE_MAX:
-      return "FILTER_TYPE_MAX";
-  }
-  return "";
-}
-
-}  // namespace
-
-FilterContext::~FilterContext() {
-}
-
-Filter::~Filter() {}
-
-// static
-std::unique_ptr<Filter> Filter::Factory(
-    const std::vector<FilterType>& filter_types,
-    const FilterContext& filter_context) {
-  if (filter_types.empty())
-    return nullptr;
-
-  std::unique_ptr<Filter> filter_list = nullptr;  // Linked list of filters.
-  for (size_t i = 0; i < filter_types.size(); i++) {
-    filter_list = PrependNewFilter(filter_types[i], filter_context,
-                                   kFilterBufSize, std::move(filter_list));
-    if (!filter_list)
-      return nullptr;
-  }
-  return filter_list;
-}
-
-// static
-std::unique_ptr<Filter> Filter::GZipFactory() {
-  return InitGZipFilter(FILTER_TYPE_GZIP, kFilterBufSize);
-}
-
-// static
-std::unique_ptr<Filter> Filter::FactoryForTests(
-    const std::vector<FilterType>& filter_types,
-    const FilterContext& filter_context,
-    int buffer_size) {
-  if (filter_types.empty())
-    return nullptr;
-
-  std::unique_ptr<Filter> filter_list;  // Linked list of filters.
-  for (size_t i = 0; i < filter_types.size(); i++) {
-    filter_list = PrependNewFilter(filter_types[i], filter_context, buffer_size,
-                                   std::move(filter_list));
-    if (!filter_list)
-      return nullptr;
-  }
-  return filter_list;
-}
-
-Filter::FilterStatus Filter::ReadData(char* dest_buffer, int* dest_len) {
-  const int dest_buffer_capacity = *dest_len;
-  if (last_status_ == FILTER_ERROR)
-    return last_status_;
-  if (!next_filter_.get())
-    return last_status_ = ReadFilteredData(dest_buffer, dest_len);
-
-  // This filter needs more data, but it's not clear that the rest of
-  // the chain does; delegate the actual status return to the next filter.
-  if (last_status_ == FILTER_NEED_MORE_DATA && !stream_data_len()) {
-    last_status_ = next_filter_->ReadData(dest_buffer, dest_len);
-    return last_status_;
-  }
-
-  do {
-    if (next_filter_->last_status() == FILTER_NEED_MORE_DATA) {
-      PushDataIntoNextFilter();
-      if (FILTER_ERROR == last_status_) {
-        *dest_len = 0;
-        return FILTER_ERROR;
-      }
-    }
-    *dest_len = dest_buffer_capacity;  // Reset the input/output parameter.
-
-    next_filter_->ReadData(dest_buffer, dest_len);
-    if (FILTER_NEED_MORE_DATA == last_status_) {
-      last_status_ = next_filter_->last_status();
-      return last_status_;
-    }
-
-    // In the case where this filter has data internally, and is indicating such
-    // with a last_status_ of FILTER_OK, but at the same time the next filter in
-    // the chain indicated it FILTER_NEED_MORE_DATA, we have to be cautious
-    // about confusing the caller. The API confusion can appear if we return
-    // FILTER_OK (suggesting we have more data in aggregate), but yet we don't
-    // populate our output buffer. When that is the case, we need to
-    // alternately call our filter element, and the next_filter element until we
-    // get out of this state (by pumping data into the next filter until it
-    // outputs data, or it runs out of data and reports that it NEED_MORE_DATA.)
-  } while (FILTER_OK == last_status_ &&
-           FILTER_NEED_MORE_DATA == next_filter_->last_status() &&
-           0 == *dest_len);
-
-  if (next_filter_->last_status() == FILTER_ERROR) {
-    last_status_ = FILTER_ERROR;
-    *dest_len = 0;
-    return FILTER_ERROR;
-  }
-  last_status_ = FILTER_OK;
-  return FILTER_OK;
-}
-
-bool Filter::FlushStreamBuffer(int stream_data_len) {
-  DCHECK_LE(stream_data_len, stream_buffer_size_);
-  if (stream_data_len <= 0 || stream_data_len > stream_buffer_size_)
-    return false;
-
-  DCHECK(stream_buffer());
-  // Bail out if there is more data in the stream buffer to be filtered.
-  if (!stream_buffer() || stream_data_len_)
-    return false;
-
-  next_stream_data_ = stream_buffer()->data();
-  stream_data_len_ = stream_data_len;
-  last_status_ = FILTER_OK;
-  return true;
-}
-
-// static
-Filter::FilterType Filter::ConvertEncodingToType(
-    const std::string& filter_type) {
-  FilterType type_id;
-  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)) {
-    type_id = FILTER_TYPE_GZIP;
-  } else if (base::LowerCaseEqualsASCII(filter_type, kSdch)) {
-    type_id = FILTER_TYPE_SDCH;
-  } else {
-    // Note we also consider "identity" and "uncompressed" UNSUPPORTED as
-    // filter should be disabled in such cases.
-    type_id = FILTER_TYPE_UNSUPPORTED;
-  }
-  return type_id;
-}
-
-// static
-void Filter::FixupEncodingTypes(
-    const FilterContext& filter_context,
-    std::vector<FilterType>* encoding_types) {
-  std::string mime_type;
-  bool success = filter_context.GetMimeType(&mime_type);
-  DCHECK(success || mime_type.empty());
-
-  // If the request was for SDCH content, then we might need additional fixups.
-  if (!filter_context.SdchDictionariesAdvertised()) {
-    // It was not an SDCH request, so we'll just record stats.
-    if (1 < encoding_types->size()) {
-      // Multiple filters were intended to only be used for SDCH (thus far!)
-      LogSdchProblem(filter_context, SDCH_MULTIENCODING_FOR_NON_SDCH_REQUEST);
-    }
-    if ((1 == encoding_types->size()) &&
-        (FILTER_TYPE_SDCH == encoding_types->front())) {
-      LogSdchProblem(filter_context,
-                     SDCH_SDCH_CONTENT_ENCODE_FOR_NON_SDCH_REQUEST);
-    }
-    return;
-  }
-
-  // The request was tagged as an SDCH request, which means the server supplied
-  // a dictionary, and we advertised it in the request. Some proxies will do
-  // very strange things to the request, or the response, so we have to handle
-  // them gracefully.
-
-  // If content encoding included SDCH, then everything is "relatively" fine.
-  if (!encoding_types->empty() &&
-      (FILTER_TYPE_SDCH == encoding_types->front())) {
-    // Some proxies (found currently in Argentina) strip the Content-Encoding
-    // text from "sdch,gzip" to a mere "sdch" without modifying the compressed
-    // payload.  To handle this gracefully, we simulate the "probably" deleted
-    // ",gzip" by appending a tentative gzip decode, which will default to a
-    // no-op pass through filter if it doesn't get gzip headers where expected.
-    if (1 == encoding_types->size()) {
-      encoding_types->push_back(FILTER_TYPE_GZIP_HELPING_SDCH);
-      LogSdchProblem(filter_context, SDCH_OPTIONAL_GUNZIP_ENCODING_ADDED);
-    }
-    return;
-  }
-
-  // There are now several cases to handle for an SDCH request. Foremost, if
-  // the outbound request was stripped so as not to advertise support for
-  // encodings, we might get back content with no encoding, or (for example)
-  // just gzip. We have to be sure that any changes we make allow for such
-  // minimal coding to work. That issue is why we use TENTATIVE filters if we
-  // add any, as those filters sniff the content, and act as pass-through
-  // filters if headers are not found.
-
-  // If the outbound GET is not modified, then the server will generally try to
-  // send us SDCH encoded content. As that content returns, there are several
-  // corruptions of the header "content-encoding" that proxies may perform (and
-  // have been detected in the wild). We already dealt with the a honest
-  // content encoding of "sdch,gzip" being corrupted into "sdch" with on change
-  // of the actual content. Another common corruption is to either disscard
-  // the accurate content encoding, or to replace it with gzip only (again, with
-  // no change in actual content). The last observed corruption it to actually
-  // change the content, such as by re-gzipping it, and that may happen along
-  // with corruption of the stated content encoding (wow!).
-
-  // The one unresolved failure mode comes when we advertise a dictionary, and
-  // the server tries to *send* a gzipped file (not gzip encode content), and
-  // then we could do a gzip decode :-(. Since SDCH is only (currently)
-  // supported server side on paths that only send HTML content, this mode has
-  // never surfaced in the wild (and is unlikely to).
-  // We will gather a lot of stats as we perform the fixups
-  if (base::StartsWith(mime_type, kTextHtml,
-                       base::CompareCase::INSENSITIVE_ASCII)) {
-    // Suspicious case: Advertised dictionary, but server didn't use sdch, and
-    // we're HTML tagged.
-    if (encoding_types->empty()) {
-      LogSdchProblem(filter_context, SDCH_ADDED_CONTENT_ENCODING);
-    } else if (1 == encoding_types->size()) {
-      LogSdchProblem(filter_context, SDCH_FIXED_CONTENT_ENCODING);
-    } else {
-      LogSdchProblem(filter_context, SDCH_FIXED_CONTENT_ENCODINGS);
-    }
-  } else {
-    // Remarkable case!?!  We advertised an SDCH dictionary, content-encoding
-    // was not marked for SDCH processing: Why did the server suggest an SDCH
-    // dictionary in the first place??. Also, the content isn't
-    // tagged as HTML, despite the fact that SDCH encoding is mostly likely for
-    // HTML: Did some anti-virus system strip this tag (sometimes they strip
-    // accept-encoding headers on the request)??  Does the content encoding not
-    // start with "text/html" for some other reason??  We'll report this as a
-    // fixup to a binary file, but it probably really is text/html (some how).
-    if (encoding_types->empty()) {
-      LogSdchProblem(filter_context, SDCH_BINARY_ADDED_CONTENT_ENCODING);
-    } else if (1 == encoding_types->size()) {
-      LogSdchProblem(filter_context, SDCH_BINARY_FIXED_CONTENT_ENCODING);
-    } else {
-      LogSdchProblem(filter_context, SDCH_BINARY_FIXED_CONTENT_ENCODINGS);
-    }
-  }
-
-  // Leave the existing encoding type to be processed first, and add our
-  // tentative decodings to be done afterwards. Vodaphone UK reportedyl will
-  // perform a second layer of gzip encoding atop the server's sdch,gzip
-  // encoding, and then claim that the content encoding is a mere gzip. As a
-  // result we'll need (in that case) to do the gunzip, plus our tentative
-  // gunzip and tentative SDCH decoding.
-  // This approach nicely handles the empty() list as well, and should work with
-  // other (as yet undiscovered) proxies the choose to re-compressed with some
-  // other encoding (such as bzip2, etc.).
-  encoding_types->insert(encoding_types->begin(),
-                         FILTER_TYPE_GZIP_HELPING_SDCH);
-  encoding_types->insert(encoding_types->begin(), FILTER_TYPE_SDCH_POSSIBLE);
-  return;
-}
-
-std::string Filter::OrderedFilterList() const {
-  if (next_filter_) {
-    return FilterTypeAsString(type_id_) + "," +
-        next_filter_->OrderedFilterList();
-  } else {
-    return FilterTypeAsString(type_id_);
-  }
-}
-
-Filter::Filter(FilterType type_id)
-    : stream_buffer_(nullptr),
-      stream_buffer_size_(0),
-      next_stream_data_(nullptr),
-      stream_data_len_(0),
-      last_status_(FILTER_NEED_MORE_DATA),
-      type_id_(type_id) {}
-
-Filter::FilterStatus Filter::CopyOut(char* dest_buffer, int* dest_len) {
-  int out_len;
-  int input_len = *dest_len;
-  *dest_len = 0;
-
-  if (0 == stream_data_len_)
-    return Filter::FILTER_NEED_MORE_DATA;
-
-  out_len = std::min(input_len, stream_data_len_);
-  memcpy(dest_buffer, next_stream_data_, out_len);
-  *dest_len += out_len;
-  stream_data_len_ -= out_len;
-  if (0 == stream_data_len_) {
-    next_stream_data_ = nullptr;
-    return Filter::FILTER_NEED_MORE_DATA;
-  } else {
-    next_stream_data_ += out_len;
-    return Filter::FILTER_OK;
-  }
-}
-
-// static
-std::unique_ptr<Filter> Filter::InitBrotliFilter(FilterType type_id,
-                                                 int buffer_size) {
-  std::unique_ptr<Filter> brotli_filter(CreateBrotliFilter(type_id));
-  if (!brotli_filter.get())
-    return nullptr;
-
-  brotli_filter->InitBuffer(buffer_size);
-  return brotli_filter;
-}
-
-// static
-std::unique_ptr<Filter> Filter::InitGZipFilter(FilterType type_id,
-                                               int buffer_size) {
-  std::unique_ptr<GZipFilter> gz_filter(new GZipFilter(type_id));
-  gz_filter->InitBuffer(buffer_size);
-  return gz_filter->InitDecoding(type_id) ? std::move(gz_filter) : nullptr;
-}
-
-// static
-std::unique_ptr<Filter> Filter::InitSdchFilter(
-    FilterType type_id,
-    const FilterContext& filter_context,
-    int buffer_size) {
-  std::unique_ptr<SdchFilter> sdch_filter(
-      new SdchFilter(type_id, filter_context));
-  sdch_filter->InitBuffer(buffer_size);
-  return sdch_filter->InitDecoding(type_id) ? std::move(sdch_filter) : nullptr;
-}
-
-// static
-std::unique_ptr<Filter> Filter::PrependNewFilter(
-    FilterType type_id,
-    const FilterContext& filter_context,
-    int buffer_size,
-    std::unique_ptr<Filter> filter_list) {
-  std::unique_ptr<Filter> first_filter;  // Soon to be start of chain.
-  switch (type_id) {
-    case FILTER_TYPE_BROTLI:
-      first_filter = InitBrotliFilter(type_id, buffer_size);
-      break;
-    case FILTER_TYPE_GZIP_HELPING_SDCH:
-    case FILTER_TYPE_DEFLATE:
-    case FILTER_TYPE_GZIP:
-      first_filter = InitGZipFilter(type_id, buffer_size);
-      break;
-    case FILTER_TYPE_SDCH:
-    case FILTER_TYPE_SDCH_POSSIBLE:
-      if (filter_context.GetURLRequestContext()->sdch_manager()) {
-        first_filter = InitSdchFilter(type_id, filter_context, buffer_size);
-      }
-      break;
-    default:
-      break;
-  }
-
-  if (!first_filter.get())
-    return nullptr;
-
-  first_filter->next_filter_ = std::move(filter_list);
-  return first_filter;
-}
-
-void Filter::InitBuffer(int buffer_size) {
-  DCHECK(!stream_buffer());
-  DCHECK_GT(buffer_size, 0);
-  stream_buffer_ = new IOBuffer(buffer_size);
-  stream_buffer_size_ = buffer_size;
-}
-
-void Filter::PushDataIntoNextFilter() {
-  IOBuffer* next_buffer = next_filter_->stream_buffer();
-  int next_size = next_filter_->stream_buffer_size();
-  last_status_ = ReadFilteredData(next_buffer->data(), &next_size);
-  if (FILTER_ERROR != last_status_)
-    next_filter_->FlushStreamBuffer(next_size);
-}
-
-}  // namespace net