net/tools/flip_server/spdy_interface.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "net/tools/flip_server/spdy_interface.h"
   6
   7 #include <algorithm>
   8 #include <string>
   9
  10 #include "net/spdy/spdy_framer.h"
  11 #include "net/spdy/spdy_protocol.h"
  12 #include "net/tools/dump_cache/url_utilities.h"
  13 #include "net/tools/flip_server/constants.h"
  14 #include "net/tools/flip_server/flip_config.h"
  15 #include "net/tools/flip_server/http_interface.h"
  16 #include "net/tools/flip_server/spdy_util.h"
  17
  18 namespace net {
  19
  20 // static
  21 std::string SpdySM::forward_ip_header_;
  22
  23 class SpdyFrameDataFrame : public DataFrame {
  24  public:
  25   explicit SpdyFrameDataFrame(SpdyFrame* spdy_frame) : frame(spdy_frame) {
  26     data = spdy_frame->data();
  27     size = spdy_frame->size();
  28   }
  29
  30   virtual ~SpdyFrameDataFrame() { delete frame; }
  31
  32   const SpdyFrame* frame;
  33 };
  34
  35 SpdySM::SpdySM(SMConnection* connection,
  36                SMInterface* sm_http_interface,
  37                EpollServer* epoll_server,
  38                MemoryCache* memory_cache,
  39                FlipAcceptor* acceptor,
  40                SpdyMajorVersion spdy_version)
  41     : buffered_spdy_framer_(new BufferedSpdyFramer(spdy_version, true)),
  42       valid_spdy_session_(false),
  43       connection_(connection),
  44       client_output_list_(connection->output_list()),
  45       client_output_ordering_(connection),
  46       next_outgoing_stream_id_(2),
  47       epoll_server_(epoll_server),
  48       acceptor_(acceptor),
  49       memory_cache_(memory_cache),
  50       close_on_error_(false) {
  51   buffered_spdy_framer_->set_visitor(this);
  52 }
  53
  54 SpdySM::~SpdySM() { }
  55
  56 void SpdySM::InitSMConnection(SMConnectionPoolInterface* connection_pool,
  57                               SMInterface* sm_interface,
  58                               EpollServer* epoll_server,
  59                               int fd,
  60                               std::string server_ip,
  61                               std::string server_port,
  62                               std::string remote_ip,
  63                               bool use_ssl) {
  64   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Initializing server connection.";
  65   connection_->InitSMConnection(connection_pool,
  66                                 sm_interface,
  67                                 epoll_server,
  68                                 fd,
  69                                 server_ip,
  70                                 server_port,
  71                                 remote_ip,
  72                                 use_ssl);
  73 }
  74
  75 SMInterface* SpdySM::NewConnectionInterface() {
  76   SMConnection* server_connection =
  77       SMConnection::NewSMConnection(epoll_server_,
  78                                     NULL,
  79                                     memory_cache_,
  80                                     acceptor_,
  81                                     "http_conn: ");
  82   if (server_connection == NULL) {
  83     LOG(ERROR) << "SpdySM: Could not create server connection";
  84     return NULL;
  85   }
  86   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Creating new HTTP interface";
  87   SMInterface* sm_http_interface =
  88       new HttpSM(server_connection, this, memory_cache_, acceptor_);
  89   return sm_http_interface;
  90 }
  91
  92 SMInterface* SpdySM::FindOrMakeNewSMConnectionInterface(
  93     const std::string& server_ip,
  94     const std::string& server_port) {
  95   SMInterface* sm_http_interface;
  96   int32 server_idx;
  97   if (unused_server_interface_list.empty()) {
  98     sm_http_interface = NewConnectionInterface();
  99     server_idx = server_interface_list.size();
 100     server_interface_list.push_back(sm_http_interface);
 101     VLOG(2) << ACCEPTOR_CLIENT_IDENT
 102             << "SpdySM: Making new server connection on index: " << server_idx;
 103   } else {
 104     server_idx = unused_server_interface_list.back();
 105     unused_server_interface_list.pop_back();
 106     sm_http_interface = server_interface_list.at(server_idx);
 107     VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Reusing connection on "
 108             << "index: " << server_idx;
 109   }
 110
 111   sm_http_interface->InitSMInterface(this, server_idx);
 112   sm_http_interface->InitSMConnection(NULL,
 113                                       sm_http_interface,
 114                                       epoll_server_,
 115                                       -1,
 116                                       server_ip,
 117                                       server_port,
 118                                       std::string(),
 119                                       false);
 120
 121   return sm_http_interface;
 122 }
 123
 124 int SpdySM::SpdyHandleNewStream(SpdyStreamId stream_id,
 125                                 SpdyPriority priority,
 126                                 const SpdyHeaderBlock& headers,
 127                                 std::string& http_data,
 128                                 bool* is_https_scheme) {
 129   *is_https_scheme = false;
 130   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: OnSyn(" << stream_id << ")";
 131   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: # headers: " << headers.size();
 132
 133   SpdyHeaderBlock::const_iterator method = headers.end();
 134   SpdyHeaderBlock::const_iterator host = headers.end();
 135   SpdyHeaderBlock::const_iterator path = headers.end();
 136   SpdyHeaderBlock::const_iterator scheme = headers.end();
 137   SpdyHeaderBlock::const_iterator version = headers.end();
 138   SpdyHeaderBlock::const_iterator url = headers.end();
 139
 140   std::string path_string, host_string, version_string;
 141
 142   if (spdy_version() == SPDY2) {
 143     url = headers.find("url");
 144     method = headers.find("method");
 145     version = headers.find("version");
 146     scheme = headers.find("scheme");
 147     if (url == headers.end() || method == headers.end() ||
 148         version == headers.end() || scheme == headers.end()) {
 149       VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: A mandatory header is "
 150               << "missing. Not creating stream";
 151       return 0;
 152     }
 153     // url->second here only ever seems to contain just the path. When this
 154     // path contains a query string with a http:// in one of its values,
 155     // UrlUtilities::GetUrlPath will fail and always return a / breaking
 156     // the request. GetUrlPath assumes the absolute URL is being passed in.
 157     path_string = UrlUtilities::GetUrlPath(url->second);
 158     host_string = UrlUtilities::GetUrlHost(url->second);
 159     version_string = version->second;
 160   } else {
 161     method = headers.find(":method");
 162     host = headers.find(":host");
 163     path = headers.find(":path");
 164     scheme = headers.find(":scheme");
 165     if (method == headers.end() || host == headers.end() ||
 166         path == headers.end() || scheme == headers.end()) {
 167       VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: A mandatory header is "
 168               << "missing. Not creating stream";
 169       return 0;
 170     }
 171     host_string = host->second;
 172     path_string = path->second;
 173     version_string = "HTTP/1.1";
 174   }
 175
 176   if (scheme->second.compare("https") == 0) {
 177     *is_https_scheme = true;
 178   }
 179
 180   if (acceptor_->flip_handler_type_ == FLIP_HANDLER_SPDY_SERVER) {
 181     VLOG(1) << ACCEPTOR_CLIENT_IDENT << "Request: " << method->second
 182             << " " << path_string;
 183     std::string filename = EncodeURL(path_string,
 184                                      host_string,
 185                                      method->second);
 186     NewStream(stream_id, priority, filename);
 187   } else {
 188     http_data +=
 189         method->second + " " + path_string + " " + version_string + "\r\n";
 190     VLOG(1) << ACCEPTOR_CLIENT_IDENT << "Request: " << method->second << " "
 191             << path_string << " " << version_string;
 192     http_data += "Host: " + (*is_https_scheme ?
 193                              acceptor_->https_server_ip_ :
 194                              acceptor_->http_server_ip_) + "\r\n";
 195     for (SpdyHeaderBlock::const_iterator i = headers.begin();
 196          i != headers.end(); ++i) {
 197       if ((i->first.size() > 0 && i->first[0] == ':') ||
 198           i->first == "host" ||
 199           i == method ||
 200           i == host ||
 201           i == path ||
 202           i == scheme ||
 203           i == version ||
 204           i == url) {
 205         // Ignore the entry.
 206       } else {
 207         http_data += i->first + ": " + i->second + "\r\n";
 208         VLOG(2) << ACCEPTOR_CLIENT_IDENT << i->first.c_str() << ":"
 209                 << i->second.c_str();
 210       }
 211     }
 212     if (forward_ip_header_.length()) {
 213       // X-Client-Cluster-IP header
 214       http_data += forward_ip_header_ + ": " +
 215           connection_->client_ip() + "\r\n";
 216     }
 217     http_data += "\r\n";
 218   }
 219
 220   VLOG(3) << ACCEPTOR_CLIENT_IDENT << "SpdySM: HTTP Request:\n" << http_data;
 221   return 1;
 222 }
 223
 224 void SpdySM::OnStreamFrameData(SpdyStreamId stream_id,
 225                                const char* data,
 226                                size_t len,
 227                                bool fin) {
 228   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: StreamData(" << stream_id
 229           << ", [" << len << "])";
 230   StreamToSmif::iterator it = stream_to_smif_.find(stream_id);
 231   if (it == stream_to_smif_.end()) {
 232     VLOG(2) << "Dropping frame from unknown stream " << stream_id;
 233     if (!valid_spdy_session_)
 234       close_on_error_ = true;
 235     return;
 236   }
 237
 238   SMInterface* interface = it->second;
 239   if (acceptor_->flip_handler_type_ == FLIP_HANDLER_PROXY)
 240     interface->ProcessWriteInput(data, len);
 241 }
 242
 243 void SpdySM::OnSynStream(SpdyStreamId stream_id,
 244                          SpdyStreamId associated_stream_id,
 245                          SpdyPriority priority,
 246                          bool fin,
 247                          bool unidirectional,
 248                          const SpdyHeaderBlock& headers) {
 249   std::string http_data;
 250   bool is_https_scheme;
 251   int ret = SpdyHandleNewStream(
 252       stream_id, priority, headers, http_data, &is_https_scheme);
 253   if (!ret) {
 254     LOG(ERROR) << "SpdySM: Could not convert spdy into http.";
 255     return;
 256   }
 257   // We've seen a valid looking SYN_STREAM, consider this to have
 258   // been a real spdy session.
 259   valid_spdy_session_ = true;
 260
 261   if (acceptor_->flip_handler_type_ == FLIP_HANDLER_PROXY) {
 262     std::string server_ip;
 263     std::string server_port;
 264     if (is_https_scheme) {
 265       server_ip = acceptor_->https_server_ip_;
 266       server_port = acceptor_->https_server_port_;
 267     } else {
 268       server_ip = acceptor_->http_server_ip_;
 269       server_port = acceptor_->http_server_port_;
 270     }
 271     SMInterface* sm_http_interface =
 272         FindOrMakeNewSMConnectionInterface(server_ip, server_port);
 273     stream_to_smif_[stream_id] = sm_http_interface;
 274     sm_http_interface->SetStreamID(stream_id);
 275     sm_http_interface->ProcessWriteInput(http_data.c_str(), http_data.size());
 276   }
 277 }
 278
 279 void SpdySM::OnSynReply(SpdyStreamId stream_id,
 280                         bool fin,
 281                         const SpdyHeaderBlock& headers) {
 282   // TODO(willchan): if there is an error parsing headers, we
 283   // should send a RST_STREAM.
 284   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: OnSynReply(" << stream_id << ")";
 285 }
 286
 287 void SpdySM::OnHeaders(SpdyStreamId stream_id,
 288                        bool fin,
 289                        const SpdyHeaderBlock& headers) {
 290   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: OnHeaders(" << stream_id << ")";
 291 }
 292
 293 void SpdySM::OnRstStream(SpdyStreamId stream_id, SpdyRstStreamStatus status) {
 294   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: OnRstStream(" << stream_id
 295           << ")";
 296   client_output_ordering_.RemoveStreamId(stream_id);
 297 }
 298
 299 bool SpdySM::OnUnknownFrame(SpdyStreamId stream_id, int frame_type) {
 300   return false;
 301 }
 302
 303 size_t SpdySM::ProcessReadInput(const char* data, size_t len) {
 304   DCHECK(buffered_spdy_framer_);
 305   return buffered_spdy_framer_->ProcessInput(data, len);
 306 }
 307
 308 size_t SpdySM::ProcessWriteInput(const char* data, size_t len) { return 0; }
 309
 310 bool SpdySM::MessageFullyRead() const {
 311   DCHECK(buffered_spdy_framer_);
 312   return buffered_spdy_framer_->MessageFullyRead();
 313 }
 314
 315 bool SpdySM::Error() const {
 316   DCHECK(buffered_spdy_framer_);
 317   return close_on_error_ || buffered_spdy_framer_->HasError();
 318 }
 319
 320 const char* SpdySM::ErrorAsString() const {
 321   DCHECK(Error());
 322   DCHECK(buffered_spdy_framer_);
 323   return SpdyFramer::ErrorCodeToString(buffered_spdy_framer_->error_code());
 324 }
 325
 326 void SpdySM::ResetForNewInterface(int32 server_idx) {
 327   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Reset for new interface: "
 328           << "server_idx: " << server_idx;
 329   unused_server_interface_list.push_back(server_idx);
 330 }
 331
 332 void SpdySM::ResetForNewConnection() {
 333   // seq_num is not cleared, intentionally.
 334   buffered_spdy_framer_.reset();
 335   valid_spdy_session_ = false;
 336   client_output_ordering_.Reset();
 337   next_outgoing_stream_id_ = 2;
 338 }
 339
 340 // Send a settings frame
 341 int SpdySM::PostAcceptHook() {
 342   // We should have buffered_spdy_framer_ set after reuse
 343   DCHECK(buffered_spdy_framer_);
 344   SettingsMap settings;
 345   settings[SETTINGS_MAX_CONCURRENT_STREAMS] =
 346       SettingsFlagsAndValue(SETTINGS_FLAG_NONE, 100);
 347   SpdyFrame* settings_frame = buffered_spdy_framer_->CreateSettings(settings);
 348
 349   VLOG(1) << ACCEPTOR_CLIENT_IDENT << "Sending Settings Frame";
 350   EnqueueDataFrame(new SpdyFrameDataFrame(settings_frame));
 351   return 1;
 352 }
 353
 354 void SpdySM::NewStream(uint32 stream_id,
 355                        uint32 priority,
 356                        const std::string& filename) {
 357   MemCacheIter mci;
 358   mci.stream_id = stream_id;
 359   mci.priority = priority;
 360   // TODO(yhirano): The program will crash when
 361   // acceptor_->flip_handler_type_ != FLIP_HANDLER_SPDY_SERVER.
 362   // It should be fixed or an assertion should be placed.
 363   if (acceptor_->flip_handler_type_ == FLIP_HANDLER_SPDY_SERVER) {
 364     if (!memory_cache_->AssignFileData(filename, &mci)) {
 365       // error creating new stream.
 366       VLOG(1) << ACCEPTOR_CLIENT_IDENT << "Sending ErrorNotFound";
 367       SendErrorNotFound(stream_id);
 368     } else {
 369       AddToOutputOrder(mci);
 370     }
 371   } else {
 372     AddToOutputOrder(mci);
 373   }
 374 }
 375
 376 void SpdySM::AddToOutputOrder(const MemCacheIter& mci) {
 377   client_output_ordering_.AddToOutputOrder(mci);
 378 }
 379
 380 void SpdySM::SendEOF(uint32 stream_id) { SendEOFImpl(stream_id); }
 381
 382 void SpdySM::SendErrorNotFound(uint32 stream_id) {
 383   SendErrorNotFoundImpl(stream_id);
 384 }
 385
 386 size_t SpdySM::SendSynStream(uint32 stream_id, const BalsaHeaders& headers) {
 387   return SendSynStreamImpl(stream_id, headers);
 388 }
 389
 390 size_t SpdySM::SendSynReply(uint32 stream_id, const BalsaHeaders& headers) {
 391   return SendSynReplyImpl(stream_id, headers);
 392 }
 393
 394 void SpdySM::SendDataFrame(uint32 stream_id,
 395                            const char* data,
 396                            int64 len,
 397                            uint32 flags,
 398                            bool compress) {
 399   SpdyDataFlags spdy_flags = static_cast<SpdyDataFlags>(flags);
 400   SendDataFrameImpl(stream_id, data, len, spdy_flags, compress);
 401 }
 402
 403 void SpdySM::SendEOFImpl(uint32 stream_id) {
 404   SendDataFrame(stream_id, NULL, 0, DATA_FLAG_FIN, false);
 405   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Sending EOF: " << stream_id;
 406   KillStream(stream_id);
 407   stream_to_smif_.erase(stream_id);
 408 }
 409
 410 void SpdySM::SendErrorNotFoundImpl(uint32 stream_id) {
 411   BalsaHeaders my_headers;
 412   my_headers.SetFirstlineFromStringPieces("HTTP/1.1", "404", "Not Found");
 413   SendSynReplyImpl(stream_id, my_headers);
 414   SendDataFrame(stream_id, "wtf?", 4, DATA_FLAG_FIN, false);
 415   client_output_ordering_.RemoveStreamId(stream_id);
 416 }
 417
 418 void SpdySM::KillStream(uint32 stream_id) {
 419   client_output_ordering_.RemoveStreamId(stream_id);
 420 }
 421
 422 void SpdySM::CopyHeaders(SpdyHeaderBlock& dest, const BalsaHeaders& headers) {
 423   for (BalsaHeaders::const_header_lines_iterator hi =
 424            headers.header_lines_begin();
 425        hi != headers.header_lines_end();
 426        ++hi) {
 427     // It is illegal to send SPDY headers with empty value or header
 428     // names.
 429     if (!hi->first.length() || !hi->second.length())
 430       continue;
 431
 432     // Key must be all lower case in SPDY headers.
 433     std::string key = hi->first.as_string();
 434     std::transform(key.begin(), key.end(), key.begin(), ::tolower);
 435     SpdyHeaderBlock::iterator fhi = dest.find(key);
 436     if (fhi == dest.end()) {
 437       dest[key] = hi->second.as_string();
 438     } else {
 439       dest[key] = (std::string(fhi->second.data(), fhi->second.size()) + "\0" +
 440                    std::string(hi->second.data(), hi->second.size()));
 441     }
 442   }
 443
 444   // These headers have no value
 445   dest.erase("X-Associated-Content");  // TODO(mbelshe): case-sensitive
 446   dest.erase("X-Original-Url");        // TODO(mbelshe): case-sensitive
 447 }
 448
 449 size_t SpdySM::SendSynStreamImpl(uint32 stream_id,
 450                                  const BalsaHeaders& headers) {
 451   SpdyHeaderBlock block;
 452   CopyHeaders(block, headers);
 453   if (spdy_version() == SPDY2) {
 454     block["method"] = headers.request_method().as_string();
 455     if (!headers.HasHeader("version"))
 456       block["version"] = headers.request_version().as_string();
 457     if (headers.HasHeader("X-Original-Url")) {
 458       std::string original_url =
 459           headers.GetHeader("X-Original-Url").as_string();
 460       block["url"] = UrlUtilities::GetUrlPath(original_url);
 461     } else {
 462       block["url"] = headers.request_uri().as_string();
 463     }
 464   } else {
 465     block[":method"] = headers.request_method().as_string();
 466     block[":version"] = headers.request_version().as_string();
 467     if (headers.HasHeader("X-Original-Url")) {
 468       std::string original_url =
 469           headers.GetHeader("X-Original-Url").as_string();
 470       block[":path"] = UrlUtilities::GetUrlPath(original_url);
 471       block[":host"] = UrlUtilities::GetUrlPath(original_url);
 472     } else {
 473       block[":path"] = headers.request_uri().as_string();
 474       if (block.find("host") != block.end()) {
 475         block[":host"] = headers.GetHeader("Host").as_string();
 476         block.erase("host");
 477       }
 478     }
 479   }
 480
 481   DCHECK(buffered_spdy_framer_);
 482   SpdyFrame* fsrcf = buffered_spdy_framer_->CreateSynStream(
 483       stream_id, 0, 0, CONTROL_FLAG_NONE, &block);
 484   size_t df_size = fsrcf->size();
 485   EnqueueDataFrame(new SpdyFrameDataFrame(fsrcf));
 486
 487   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Sending SynStreamheader "
 488           << stream_id;
 489   return df_size;
 490 }
 491
 492 size_t SpdySM::SendSynReplyImpl(uint32 stream_id, const BalsaHeaders& headers) {
 493   SpdyHeaderBlock block;
 494   CopyHeaders(block, headers);
 495   if (spdy_version() == SPDY2) {
 496     block["status"] = headers.response_code().as_string() + " " +
 497         headers.response_reason_phrase().as_string();
 498     block["version"] = headers.response_version().as_string();
 499   } else {
 500     block[":status"] = headers.response_code().as_string() + " " +
 501         headers.response_reason_phrase().as_string();
 502     block[":version"] = headers.response_version().as_string();
 503   }
 504
 505   DCHECK(buffered_spdy_framer_);
 506   SpdyFrame* fsrcf = buffered_spdy_framer_->CreateSynReply(
 507       stream_id, CONTROL_FLAG_NONE, &block);
 508   size_t df_size = fsrcf->size();
 509   EnqueueDataFrame(new SpdyFrameDataFrame(fsrcf));
 510
 511   VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Sending SynReplyheader "
 512           << stream_id;
 513   return df_size;
 514 }
 515
 516 void SpdySM::SendDataFrameImpl(uint32 stream_id,
 517                                const char* data,
 518                                int64 len,
 519                                SpdyDataFlags flags,
 520                                bool compress) {
 521   DCHECK(buffered_spdy_framer_);
 522   // TODO(mbelshe):  We can't compress here - before going into the
 523   //                 priority queue.  Compression needs to be done
 524   //                 with late binding.
 525   if (len == 0) {
 526     SpdyFrame* fdf =
 527         buffered_spdy_framer_->CreateDataFrame(stream_id, data, len, flags);
 528     EnqueueDataFrame(new SpdyFrameDataFrame(fdf));
 529     return;
 530   }
 531
 532   // Chop data frames into chunks so that one stream can't monopolize the
 533   // output channel.
 534   while (len > 0) {
 535     int64 size = std::min(len, static_cast<int64>(kSpdySegmentSize));
 536     SpdyDataFlags chunk_flags = flags;
 537
 538     // If we chunked this block, and the FIN flag was set, there is more
 539     // data coming.  So, remove the flag.
 540     if ((size < len) && (flags & DATA_FLAG_FIN))
 541       chunk_flags = static_cast<SpdyDataFlags>(chunk_flags & ~DATA_FLAG_FIN);
 542
 543     SpdyFrame* fdf = buffered_spdy_framer_->CreateDataFrame(
 544         stream_id, data, size, chunk_flags);
 545     EnqueueDataFrame(new SpdyFrameDataFrame(fdf));
 546
 547     VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: Sending data frame "
 548             << stream_id << " [" << size << "] shrunk to "
 549             << (fdf->size() - kSpdyOverhead) << ", flags=" << flags;
 550
 551     data += size;
 552     len -= size;
 553   }
 554 }
 555
 556 void SpdySM::EnqueueDataFrame(DataFrame* df) {
 557   connection_->EnqueueDataFrame(df);
 558 }
 559
 560 void SpdySM::GetOutput() {
 561   while (client_output_list_->size() < 2) {
 562     MemCacheIter* mci = client_output_ordering_.GetIter();
 563     if (mci == NULL) {
 564       VLOG(2) << ACCEPTOR_CLIENT_IDENT
 565               << "SpdySM: GetOutput: nothing to output!?";
 566       return;
 567     }
 568     if (!mci->transformed_header) {
 569       mci->transformed_header = true;
 570       VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: GetOutput transformed "
 571               << "header stream_id: [" << mci->stream_id << "]";
 572       if ((mci->stream_id % 2) == 0) {
 573         // this is a server initiated stream.
 574         // Ideally, we'd do a 'syn-push' here, instead of a syn-reply.
 575         BalsaHeaders headers;
 576         headers.CopyFrom(*(mci->file_data->headers()));
 577         headers.ReplaceOrAppendHeader("status", "200");
 578         headers.ReplaceOrAppendHeader("version", "http/1.1");
 579         headers.SetRequestFirstlineFromStringPieces(
 580             "PUSH", mci->file_data->filename(), "");
 581         mci->bytes_sent = SendSynStream(mci->stream_id, headers);
 582       } else {
 583         BalsaHeaders headers;
 584         headers.CopyFrom(*(mci->file_data->headers()));
 585         mci->bytes_sent = SendSynReply(mci->stream_id, headers);
 586       }
 587       return;
 588     }
 589     if (mci->body_bytes_consumed >= mci->file_data->body().size()) {
 590       VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: GetOutput "
 591               << "remove_stream_id: [" << mci->stream_id << "]";
 592       SendEOF(mci->stream_id);
 593       return;
 594     }
 595     size_t num_to_write =
 596         mci->file_data->body().size() - mci->body_bytes_consumed;
 597     if (num_to_write > mci->max_segment_size)
 598       num_to_write = mci->max_segment_size;
 599
 600     bool should_compress = false;
 601     if (!mci->file_data->headers()->HasHeader("content-encoding")) {
 602       if (mci->file_data->headers()->HasHeader("content-type")) {
 603         std::string content_type =
 604             mci->file_data->headers()->GetHeader("content-type").as_string();
 605         if (content_type.find("image") == content_type.npos)
 606           should_compress = true;
 607       }
 608     }
 609
 610     SendDataFrame(mci->stream_id,
 611                   mci->file_data->body().data() + mci->body_bytes_consumed,
 612                   num_to_write,
 613                   0,
 614                   should_compress);
 615     VLOG(2) << ACCEPTOR_CLIENT_IDENT << "SpdySM: GetOutput SendDataFrame["
 616             << mci->stream_id << "]: " << num_to_write;
 617     mci->body_bytes_consumed += num_to_write;
 618     mci->bytes_sent += num_to_write;
 619   }
 620 }
 621
 622 void SpdySM::CreateFramer(SpdyMajorVersion spdy_version) {
 623   DCHECK(!buffered_spdy_framer_);
 624   buffered_spdy_framer_.reset(new BufferedSpdyFramer(spdy_version, true));
 625   buffered_spdy_framer_->set_visitor(this);
 626 }
 627
 628 }  // namespace net