Http Cache: Split HttpCache::Transaction to its own set...

net/http/http_cache_transaction.cc

Index: net/http/http_cache_transaction.cc
===================================================================
--- net/http/http_cache_transaction.cc	(revision 31582)
+++ net/http/http_cache_transaction.cc	(working copy)
@@ -2,19 +2,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "net/http/http_cache.h"
+#include "net/http/http_cache_transaction.h"
 
-#include <algorithm>
-#include <string>
-
 #include "base/compiler_specific.h"
 
 #if defined(OS_POSIX)
 #include <unistd.h>
 #endif
 
-#include "base/message_loop.h"
-#include "base/pickle.h"
 #include "base/ref_counted.h"
 #include "base/string_util.h"
 #include "base/time.h"
@@ -24,11 +19,8 @@
 #include "net/base/net_errors.h"
 #include "net/base/ssl_cert_request_info.h"
 #include "net/disk_cache/disk_cache.h"
-#include "net/http/http_network_layer.h"
-#include "net/http/http_network_session.h"
 #include "net/http/http_request_info.h"
 #include "net/http/http_response_headers.h"
-#include "net/http/http_response_info.h"
 #include "net/http/http_transaction.h"
 #include "net/http/http_util.h"
 #include "net/http/partial_data.h"
@@ -69,15 +61,6 @@
   { "if-none-match", "etag" },
 };
 
-// Helper struct to pair a header name with its value, for
-// headers used to validate cache entries.
-struct ValidationHeaders {
-  ValidationHeaders() : initialized(false) {}
-
-  std::string values[ARRAYSIZE_UNSAFE(kValidationHeaders)];
-  bool initialized;
-};
-
 // If the request includes one of these request headers, then avoid reusing
 // our cached copy if any.
 static const HeaderNameAndValue kForceFetchHeaders[] = {
@@ -113,282 +96,38 @@
 
 //-----------------------------------------------------------------------------
 
-HttpCache::ActiveEntry::ActiveEntry(disk_cache::Entry* e)
-    : disk_entry(e),
-      writer(NULL),
-      will_process_pending_queue(false),
-      doomed(false) {
+HttpCache::Transaction::Transaction(HttpCache* cache, bool enable_range_support)
+    : request_(NULL),
+      cache_(cache->AsWeakPtr()),
+      entry_(NULL),
+      network_trans_(NULL),
+      callback_(NULL),
+      mode_(NONE),
+      reading_(false),
+      invalid_range_(false),
+      enable_range_support_(enable_range_support),
+      truncated_(false),
+      read_offset_(0),
+      effective_load_flags_(0),
+      final_upload_progress_(0),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          network_info_callback_(this, &Transaction::OnNetworkInfoAvailable)),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          network_read_callback_(this, &Transaction::OnNetworkReadCompleted)),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          cache_read_callback_(new CancelableCompletionCallback<Transaction>(
+              this, &Transaction::OnCacheReadCompleted))),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          cache_write_callback_(new CancelableCompletionCallback<Transaction>(
+              this, &Transaction::OnCacheWriteCompleted))),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          entry_ready_callback_(new CancelableCompletionCallback<Transaction>(
+                this, &Transaction::OnCacheEntryReady))) {
+  COMPILE_ASSERT(HttpCache::Transaction::kNumValidationHeaders ==
+                     ARRAYSIZE_UNSAFE(kValidationHeaders),
+                 Invalid_number_of_validation_headers);
 }
 
-HttpCache::ActiveEntry::~ActiveEntry() {
-  if (disk_entry)
-    disk_entry->Close();
-}
-
-//-----------------------------------------------------------------------------
-
-class HttpCache::Transaction : public HttpTransaction {
- public:
-  Transaction(HttpCache* cache, bool enable_range_support)
-      : request_(NULL),
-        cache_(cache->AsWeakPtr()),
-        entry_(NULL),
-        network_trans_(NULL),
-        callback_(NULL),
-        mode_(NONE),
-        reading_(false),
-        invalid_range_(false),
-        enable_range_support_(enable_range_support),
-        truncated_(false),
-        read_offset_(0),
-        effective_load_flags_(0),
-        final_upload_progress_(0),
-        ALLOW_THIS_IN_INITIALIZER_LIST(
-            network_info_callback_(this, &Transaction::OnNetworkInfoAvailable)),
-        ALLOW_THIS_IN_INITIALIZER_LIST(
-            network_read_callback_(this, &Transaction::OnNetworkReadCompleted)),
-        ALLOW_THIS_IN_INITIALIZER_LIST(
-            cache_read_callback_(new CancelableCompletionCallback<Transaction>(
-                this, &Transaction::OnCacheReadCompleted))),
-        ALLOW_THIS_IN_INITIALIZER_LIST(
-            cache_write_callback_(new CancelableCompletionCallback<Transaction>(
-                this, &Transaction::OnCacheWriteCompleted))),
-        ALLOW_THIS_IN_INITIALIZER_LIST(
-            entry_ready_callback_(new CancelableCompletionCallback<Transaction>(
-                this, &Transaction::OnCacheEntryReady))) {
-  }
-
-  // Clean up the transaction.
-  virtual ~Transaction();
-
-  // HttpTransaction methods:
-  virtual int Start(const HttpRequestInfo*, CompletionCallback*, LoadLog*);
-  virtual int RestartIgnoringLastError(CompletionCallback*);
-  virtual int RestartWithCertificate(X509Certificate* client_cert,
-                                     CompletionCallback* callback);
-  virtual int RestartWithAuth(const std::wstring& username,
-                              const std::wstring& password,
-                              CompletionCallback* callback);
-  virtual bool IsReadyToRestartForAuth();
-  virtual int Read(IOBuffer* buf, int buf_len, CompletionCallback*);
-  virtual const HttpResponseInfo* GetResponseInfo() const;
-  virtual LoadState GetLoadState() const;
-  virtual uint64 GetUploadProgress(void) const;
-
-  // The transaction has the following modes, which apply to how it may access
-  // its cache entry.
-  //
-  //  o If the mode of the transaction is NONE, then it is in "pass through"
-  //    mode and all methods just forward to the inner network transaction.
-  //
-  //  o If the mode of the transaction is only READ, then it may only read from
-  //    the cache entry.
-  //
-  //  o If the mode of the transaction is only WRITE, then it may only write to
-  //    the cache entry.
-  //
-  //  o If the mode of the transaction is READ_WRITE, then the transaction may
-  //    optionally modify the cache entry (e.g., possibly corresponding to
-  //    cache validation).
-  //
-  //  o If the mode of the transaction is UPDATE, then the transaction may
-  //    update existing cache entries, but will never create a new entry or
-  //    respond using the entry read from the cache.
-  enum Mode {
-    NONE            = 0,
-    READ_META       = 1 << 0,
-    READ_DATA       = 1 << 1,
-    READ            = READ_META | READ_DATA,
-    WRITE           = 1 << 2,
-    READ_WRITE      = READ | WRITE,
-    UPDATE          = READ_META | WRITE,  // READ_WRITE & ~READ_DATA
-  };
-
-  Mode mode() const { return mode_; }
-
-  const std::string& key() const { return cache_key_; }
-
-  // Associates this transaction with a cache entry.
-  int AddToEntry();
-
-  // Called by the HttpCache when the given disk cache entry becomes accessible
-  // to the transaction.  Returns network error code.
-  int EntryAvailable(ActiveEntry* entry);
-
-  // This transaction is being deleted and we are not done writing to the cache.
-  // We need to indicate that the response data was truncated.  Returns true on
-  // success.
-  bool AddTruncatedFlag();
-
- private:
-  // This is a helper function used to trigger a completion callback.  It may
-  // only be called if callback_ is non-null.
-  void DoCallback(int rv);
-
-  // This will trigger the completion callback if appropriate.
-  int HandleResult(int rv);
-
-  // Sets request_ and fields derived from it.
-  void SetRequest(LoadLog* load_log, const HttpRequestInfo* request);
-
-  // Returns true if the request should be handled exclusively by the network
-  // layer (skipping the cache entirely).
-  bool ShouldPassThrough();
-
-  // Called to begin reading from the cache.  Returns network error code.
-  int BeginCacheRead();
-
-  // Called to begin validating the cache entry.  Returns network error code.
-  int BeginCacheValidation();
-
-  // Called to begin validating an entry that stores partial content.  Returns
-  // a network error code.
-  int BeginPartialCacheValidation();
-
-  // Validates the entry headers against the requested range and continues with
-  // the validation of the rest of the entry.  Returns a network error code.
-  int ValidateEntryHeadersAndContinue(bool byte_range_requested);
-
-  // Performs the cache validation for the next chunk of data stored by the
-  // cache.  If this chunk is not currently stored, starts the network request
-  // to fetch it.  Returns a network error code.
-  int ContinuePartialCacheValidation();
-
-  // Called to start requests which were given an "if-modified-since" or
-  // "if-none-match" validation header by the caller (NOT when the request was
-  // conditionalized internally in response to LOAD_VALIDATE_CACHE).
-  // Returns a network error code.
-  int BeginExternallyConditionalizedRequest();
-
-  // Called to begin a network transaction.  Returns network error code.
-  int BeginNetworkRequest();
-
-  // Called to restart a network transaction after an error.  Returns network
-  // error code.
-  int RestartNetworkRequest();
-
-  // Called to restart a network transaction with a client certificate.
-  // Returns network error code.
-  int RestartNetworkRequestWithCertificate(X509Certificate* client_cert);
-
-  // Called to restart a network transaction with authentication credentials.
-  // Returns network error code.
-  int RestartNetworkRequestWithAuth(const std::wstring& username,
-                                    const std::wstring& password);
-
-  // Called to determine if we need to validate the cache entry before using it.
-  bool RequiresValidation();
-
-  // Called to make the request conditional (to ask the server if the cached
-  // copy is valid).  Returns true if able to make the request conditional.
-  bool ConditionalizeRequest();
-
-  // Makes sure that a 206 response is expected.  Returns a network error code.
-  bool ValidatePartialResponse(const HttpResponseHeaders* headers);
-
-  // Handles a response validation error by bypassing the cache.
-  void IgnoreRangeRequest();
-
-  // Reads data from the network.
-  int ReadFromNetwork(IOBuffer* data, int data_len);
-
-  // Reads data from the cache entry.
-  int ReadFromEntry(IOBuffer* data, int data_len);
-
-  // Called to populate response_ from the cache entry.
-  int ReadResponseInfoFromEntry();
-
-  // Called to write data to the cache entry.  If the write fails, then the
-  // cache entry is destroyed.  Future calls to this function will just do
-  // nothing without side-effect.  Returns a network error code.
-  int WriteToEntry(int index, int offset, IOBuffer* data, int data_len,
-                   CompletionCallback* callback);
-
-  // Called to write response_ to the cache entry. |truncated| indicates if the
-  // entry should be marked as incomplete.
-  void WriteResponseInfoToEntry(bool truncated);
-
-  // Called to append response data to the cache entry.  Returns a network error
-  // code.
-  int AppendResponseDataToEntry(IOBuffer* data, int data_len,
-                                CompletionCallback* callback);
-
-  // Called to truncate response content in the entry.
-  void TruncateResponseData();
-
-  // Called when we are done writing to the cache entry.
-  void DoneWritingToEntry(bool success);
-
-  // Deletes the current partial cache entry (sparse), and optionally removes
-  // the control object (partial_).
-  void DoomPartialEntry(bool delete_object);
-
-  // Performs the needed work after receiving data from the network.
-  int DoNetworkReadCompleted(int result);
-
-  // Performs the needed work after receiving data from the network, when
-  // working with range requests.
-  int DoPartialNetworkReadCompleted(int result);
-
-  // Performs the needed work after receiving data from the cache.
-  int DoCacheReadCompleted(int result);
-
-  // Performs the needed work after receiving data from the cache, when
-  // working with range requests.
-  int DoPartialCacheReadCompleted(int result);
-
-  // Performs the needed work after writing data to the cache.
-  int DoCacheWriteCompleted(int result);
-
-  // Called to signal completion of the network transaction's Start method:
-  void OnNetworkInfoAvailable(int result);
-
-  // Called to signal completion of the network transaction's Read method:
-  void OnNetworkReadCompleted(int result);
-
-  // Called to signal completion of the cache's ReadData method:
-  void OnCacheReadCompleted(int result);
-
-  // Called to signal completion of the cache's WriteData method:
-  void OnCacheWriteCompleted(int result);
-
-  // Called to signal completion of the cache entry's ReadyForSparseIO method:
-  void OnCacheEntryReady(int result);
-
-  scoped_refptr<LoadLog> load_log_;
-  const HttpRequestInfo* request_;
-  scoped_ptr<HttpRequestInfo> custom_request_;
-  // If extra_headers specified a "if-modified-since" or "if-none-match",
-  // |external_validation_| contains the value of those headers.
-  ValidationHeaders external_validation_;
-  base::WeakPtr<HttpCache> cache_;
-  HttpCache::ActiveEntry* entry_;
-  scoped_ptr<HttpTransaction> network_trans_;
-  CompletionCallback* callback_;  // Consumer's callback.
-  HttpResponseInfo response_;
-  HttpResponseInfo auth_response_;
-  std::string cache_key_;
-  Mode mode_;
-  bool reading_;  // We are already reading.
-  bool invalid_range_;  // We may bypass the cache for this request.
-  bool enable_range_support_;
-  bool truncated_;  // We don't have all the response data.
-  scoped_refptr<IOBuffer> read_buf_;
-  int read_buf_len_;
-  int read_offset_;
-  int effective_load_flags_;
-  scoped_ptr<PartialData> partial_;  // We are dealing with range requests.
-  uint64 final_upload_progress_;
-  CompletionCallbackImpl<Transaction> network_info_callback_;
-  CompletionCallbackImpl<Transaction> network_read_callback_;
-  scoped_refptr<CancelableCompletionCallback<Transaction> >
-      cache_read_callback_;
-  scoped_refptr<CancelableCompletionCallback<Transaction> >
-      cache_write_callback_;
-  scoped_refptr<CancelableCompletionCallback<Transaction> >
-      entry_ready_callback_;
-};
-
 HttpCache::Transaction::~Transaction() {
   if (cache_) {
     if (entry_) {
@@ -1629,487 +1368,4 @@
   ValidateEntryHeadersAndContinue(true);
 }
 
-//-----------------------------------------------------------------------------
-
-HttpCache::HttpCache(HostResolver* host_resolver,
-                     ProxyService* proxy_service,
-                     SSLConfigService* ssl_config_service,
-                     const FilePath& cache_dir,
-                     int cache_size)
-    : disk_cache_dir_(cache_dir),
-      mode_(NORMAL),
-      type_(DISK_CACHE),
-      network_layer_(HttpNetworkLayer::CreateFactory(
-          host_resolver, proxy_service, ssl_config_service)),
-      ALLOW_THIS_IN_INITIALIZER_LIST(task_factory_(this)),
-      enable_range_support_(true),
-      cache_size_(cache_size) {
-}
-
-HttpCache::HttpCache(HttpNetworkSession* session,
-                     const FilePath& cache_dir,
-                     int cache_size)
-    : disk_cache_dir_(cache_dir),
-      mode_(NORMAL),
-      type_(DISK_CACHE),
-      network_layer_(HttpNetworkLayer::CreateFactory(session)),
-      ALLOW_THIS_IN_INITIALIZER_LIST(task_factory_(this)),
-      enable_range_support_(true),
-      cache_size_(cache_size) {
-}
-
-HttpCache::HttpCache(HostResolver* host_resolver,
-                     ProxyService* proxy_service,
-                     SSLConfigService* ssl_config_service,
-                     int cache_size)
-    : mode_(NORMAL),
-      type_(MEMORY_CACHE),
-      network_layer_(HttpNetworkLayer::CreateFactory(
-          host_resolver, proxy_service, ssl_config_service)),
-      ALLOW_THIS_IN_INITIALIZER_LIST(task_factory_(this)),
-      enable_range_support_(true),
-      cache_size_(cache_size) {
-}
-
-HttpCache::HttpCache(HttpTransactionFactory* network_layer,
-                     disk_cache::Backend* disk_cache)
-    : mode_(NORMAL),
-      type_(DISK_CACHE),
-      network_layer_(network_layer),
-      disk_cache_(disk_cache),
-      ALLOW_THIS_IN_INITIALIZER_LIST(task_factory_(this)),
-      enable_range_support_(true),
-      cache_size_(0) {
-}
-
-HttpCache::~HttpCache() {
-  // If we have any active entries remaining, then we need to deactivate them.
-  // We may have some pending calls to OnProcessPendingQueue, but since those
-  // won't run (due to our destruction), we can simply ignore the corresponding
-  // will_process_pending_queue flag.
-  while (!active_entries_.empty()) {
-    ActiveEntry* entry = active_entries_.begin()->second;
-    entry->will_process_pending_queue = false;
-    entry->pending_queue.clear();
-    entry->readers.clear();
-    entry->writer = NULL;
-    DeactivateEntry(entry);
-  }
-
-  ActiveEntriesSet::iterator it = doomed_entries_.begin();
-  for (; it != doomed_entries_.end(); ++it)
-    delete *it;
-}
-
-disk_cache::Backend* HttpCache::GetBackend() {
-  if (disk_cache_.get())
-    return disk_cache_.get();
-
-  DCHECK_GE(cache_size_, 0);
-  if (type_ == MEMORY_CACHE) {
-    // We may end up with no folder name and no cache if the initialization
-    // of the disk cache fails. We want to be sure that what we wanted to have
-    // was an in-memory cache.
-    disk_cache_.reset(disk_cache::CreateInMemoryCacheBackend(cache_size_));
-  } else if (!disk_cache_dir_.empty()) {
-    disk_cache_.reset(disk_cache::CreateCacheBackend(disk_cache_dir_, true,
-        cache_size_, type_));
-    disk_cache_dir_ = FilePath();  // Reclaim memory.
-  }
-  return disk_cache_.get();
-}
-
-int HttpCache::CreateTransaction(scoped_ptr<HttpTransaction>* trans) {
-  // Do lazy initialization of disk cache if needed.
-  GetBackend();
-  trans->reset(new HttpCache::Transaction(this, enable_range_support_));
-  return OK;
-}
-
-HttpCache* HttpCache::GetCache() {
-  return this;
-}
-
-HttpNetworkSession* HttpCache::GetSession() {
-  net::HttpNetworkLayer* network =
-      static_cast<net::HttpNetworkLayer*>(network_layer_.get());
-  return network->GetSession();
-}
-
-void HttpCache::Suspend(bool suspend) {
-  network_layer_->Suspend(suspend);
-}
-
-// static
-bool HttpCache::ParseResponseInfo(const char* data, int len,
-                                  HttpResponseInfo* response_info,
-                                  bool* response_truncated) {
-  Pickle pickle(data, len);
-  return response_info->InitFromPickle(pickle, response_truncated);
-}
-
-// static
-bool HttpCache::ReadResponseInfo(disk_cache::Entry* disk_entry,
-                                 HttpResponseInfo* response_info,
-                                 bool* response_truncated) {
-  int size = disk_entry->GetDataSize(kResponseInfoIndex);
-
-  scoped_refptr<IOBuffer> buffer = new IOBuffer(size);
-  int rv = disk_entry->ReadData(kResponseInfoIndex, 0, buffer, size, NULL);
-  if (rv != size) {
-    DLOG(ERROR) << "ReadData failed: " << rv;
-    return false;
-  }
-
-  return ParseResponseInfo(buffer->data(), size, response_info,
-                           response_truncated);
-}
-
-// static
-bool HttpCache::WriteResponseInfo(disk_cache::Entry* disk_entry,
-                                  const HttpResponseInfo* response_info,
-                                  bool skip_transient_headers,
-                                  bool response_truncated) {
-  Pickle pickle;
-  response_info->Persist(
-      &pickle, skip_transient_headers, response_truncated);
-
-  scoped_refptr<WrappedIOBuffer> data = new WrappedIOBuffer(
-      reinterpret_cast<const char*>(pickle.data()));
-  int len = static_cast<int>(pickle.size());
-
-  return disk_entry->WriteData(kResponseInfoIndex, 0, data, len, NULL,
-                               true) == len;
-}
-
-// Generate a key that can be used inside the cache.
-std::string HttpCache::GenerateCacheKey(const HttpRequestInfo* request) {
-  // Strip out the reference, username, and password sections of the URL.
-  std::string url = HttpUtil::SpecForRequest(request->url);
-
-  DCHECK(mode_ != DISABLE);
-  if (mode_ == NORMAL) {
-    // No valid URL can begin with numerals, so we should not have to worry
-    // about collisions with normal URLs.
-    if (request->upload_data && request->upload_data->identifier())
-      url.insert(0, StringPrintf("%lld/", request->upload_data->identifier()));
-    return url;
-  }
-
-  // In playback and record mode, we cache everything.
-
-  // Lazily initialize.
-  if (playback_cache_map_ == NULL)
-    playback_cache_map_.reset(new PlaybackCacheMap());
-
-  // Each time we request an item from the cache, we tag it with a
-  // generation number.  During playback, multiple fetches for the same
-  // item will use the same generation number and pull the proper
-  // instance of an URL from the cache.
-  int generation = 0;
-  DCHECK(playback_cache_map_ != NULL);
-  if (playback_cache_map_->find(url) != playback_cache_map_->end())
-    generation = (*playback_cache_map_)[url];
-  (*playback_cache_map_)[url] = generation + 1;
-
-  // The key into the cache is GENERATION # + METHOD + URL.
-  std::string result = IntToString(generation);
-  result.append(request->method);
-  result.append(url);
-  return result;
-}
-
-void HttpCache::DoomEntry(const std::string& key) {
-  // Need to abandon the ActiveEntry, but any transaction attached to the entry
-  // should not be impacted.  Dooming an entry only means that it will no
-  // longer be returned by FindActiveEntry (and it will also be destroyed once
-  // all consumers are finished with the entry).
-  ActiveEntriesMap::iterator it = active_entries_.find(key);
-  if (it == active_entries_.end()) {
-    disk_cache_->DoomEntry(key);
-  } else {
-    ActiveEntry* entry = it->second;
-    active_entries_.erase(it);
-
-    // We keep track of doomed entries so that we can ensure that they are
-    // cleaned up properly when the cache is destroyed.
-    doomed_entries_.insert(entry);
-
-    entry->disk_entry->Doom();
-    entry->doomed = true;
-
-    DCHECK(entry->writer || !entry->readers.empty());
-  }
-}
-
-void HttpCache::FinalizeDoomedEntry(ActiveEntry* entry) {
-  DCHECK(entry->doomed);
-  DCHECK(!entry->writer);
-  DCHECK(entry->readers.empty());
-  DCHECK(entry->pending_queue.empty());
-
-  ActiveEntriesSet::iterator it = doomed_entries_.find(entry);
-  DCHECK(it != doomed_entries_.end());
-  doomed_entries_.erase(it);
-
-  delete entry;
-}
-
-HttpCache::ActiveEntry* HttpCache::FindActiveEntry(const std::string& key) {
-  ActiveEntriesMap::const_iterator it = active_entries_.find(key);
-  return it != active_entries_.end() ? it->second : NULL;
-}
-
-HttpCache::ActiveEntry* HttpCache::OpenEntry(const std::string& key) {
-  DCHECK(!FindActiveEntry(key));
-
-  disk_cache::Entry* disk_entry;
-  if (!disk_cache_->OpenEntry(key, &disk_entry))
-    return NULL;
-
-  return ActivateEntry(key, disk_entry);
-}
-
-HttpCache::ActiveEntry* HttpCache::CreateEntry(const std::string& key) {
-  DCHECK(!FindActiveEntry(key));
-
-  disk_cache::Entry* disk_entry;
-  if (!disk_cache_->CreateEntry(key, &disk_entry))
-    return NULL;
-
-  return ActivateEntry(key, disk_entry);
-}
-
-void HttpCache::DestroyEntry(ActiveEntry* entry) {
-  if (entry->doomed) {
-    FinalizeDoomedEntry(entry);
-  } else {
-    DeactivateEntry(entry);
-  }
-}
-
-HttpCache::ActiveEntry* HttpCache::ActivateEntry(
-    const std::string& key,
-    disk_cache::Entry* disk_entry) {
-  ActiveEntry* entry = new ActiveEntry(disk_entry);
-  active_entries_[key] = entry;
-  return entry;
-}
-
-void HttpCache::DeactivateEntry(ActiveEntry* entry) {
-  DCHECK(!entry->will_process_pending_queue);
-  DCHECK(!entry->doomed);
-  DCHECK(!entry->writer);
-  DCHECK(entry->readers.empty());
-  DCHECK(entry->pending_queue.empty());
-
-  std::string key = entry->disk_entry->GetKey();
-  if (key.empty())
-    return SlowDeactivateEntry(entry);
-
-  ActiveEntriesMap::iterator it = active_entries_.find(key);
-  DCHECK(it != active_entries_.end());
-  DCHECK(it->second == entry);
-
-  active_entries_.erase(it);
-  delete entry;
-}
-
-// We don't know this entry's key so we have to find it without it.
-void HttpCache::SlowDeactivateEntry(ActiveEntry* entry) {
-  for (ActiveEntriesMap::iterator it = active_entries_.begin();
-       it != active_entries_.end(); ++it) {
-    if (it->second == entry) {
-      active_entries_.erase(it);
-      delete entry;
-      break;
-    }
-  }
-}
-
-int HttpCache::AddTransactionToEntry(ActiveEntry* entry, Transaction* trans) {
-  DCHECK(entry);
-
-  // We implement a basic reader/writer lock for the disk cache entry.  If
-  // there is already a writer, then everyone has to wait for the writer to
-  // finish before they can access the cache entry.  There can be multiple
-  // readers.
-  //
-  // NOTE: If the transaction can only write, then the entry should not be in
-  // use (since any existing entry should have already been doomed).
-
-  if (entry->writer || entry->will_process_pending_queue) {
-    entry->pending_queue.push_back(trans);
-    return ERR_IO_PENDING;
-  }
-
-  if (trans->mode() & Transaction::WRITE) {
-    // transaction needs exclusive access to the entry
-    if (entry->readers.empty()) {
-      entry->writer = trans;
-    } else {
-      entry->pending_queue.push_back(trans);
-      return ERR_IO_PENDING;
-    }
-  } else {
-    // transaction needs read access to the entry
-    entry->readers.push_back(trans);
-  }
-
-  // We do this before calling EntryAvailable to force any further calls to
-  // AddTransactionToEntry to add their transaction to the pending queue, which
-  // ensures FIFO ordering.
-  if (!entry->writer && !entry->pending_queue.empty())
-    ProcessPendingQueue(entry);
-
-  return trans->EntryAvailable(entry);
-}
-
-void HttpCache::DoneWithEntry(ActiveEntry* entry, Transaction* trans,
-                              bool cancel) {
-  // If we already posted a task to move on to the next transaction and this was
-  // the writer, there is nothing to cancel.
-  if (entry->will_process_pending_queue && entry->readers.empty())
-    return;
-
-  if (entry->writer) {
-    DCHECK(trans == entry->writer);
-
-    // Assume there was a failure.
-    bool success = false;
-    if (cancel) {
-      DCHECK(entry->disk_entry);
-      // This is a successful operation in the sense that we want to keep the
-      // entry.
-      success = trans->AddTruncatedFlag();
-    }
-    DoneWritingToEntry(entry, success);
-  } else {
-    DoneReadingFromEntry(entry, trans);
-  }
-}
-
-void HttpCache::DoneWritingToEntry(ActiveEntry* entry, bool success) {
-  DCHECK(entry->readers.empty());
-
-  entry->writer = NULL;
-
-  if (success) {
-    ProcessPendingQueue(entry);
-  } else {
-    DCHECK(!entry->will_process_pending_queue);
-
-    // We failed to create this entry.
-    TransactionList pending_queue;
-    pending_queue.swap(entry->pending_queue);
-
-    entry->disk_entry->Doom();
-    DestroyEntry(entry);
-
-    // We need to do something about these pending entries, which now need to
-    // be added to a new entry.
-    while (!pending_queue.empty()) {
-      pending_queue.front()->AddToEntry();
-      pending_queue.pop_front();
-    }
-  }
-}
-
-void HttpCache::DoneReadingFromEntry(ActiveEntry* entry, Transaction* trans) {
-  DCHECK(!entry->writer);
-
-  TransactionList::iterator it =
-      std::find(entry->readers.begin(), entry->readers.end(), trans);
-  DCHECK(it != entry->readers.end());
-
-  entry->readers.erase(it);
-
-  ProcessPendingQueue(entry);
-}
-
-void HttpCache::ConvertWriterToReader(ActiveEntry* entry) {
-  DCHECK(entry->writer);
-  DCHECK(entry->writer->mode() == Transaction::READ_WRITE);
-  DCHECK(entry->readers.empty());
-
-  Transaction* trans = entry->writer;
-
-  entry->writer = NULL;
-  entry->readers.push_back(trans);
-
-  ProcessPendingQueue(entry);
-}
-
-void HttpCache::RemovePendingTransaction(Transaction* trans) {
-  ActiveEntriesMap::const_iterator i = active_entries_.find(trans->key());
-  bool found = false;
-  if (i != active_entries_.end())
-    found = RemovePendingTransactionFromEntry(i->second, trans);
-
-  if (found)
-    return;
-
-  ActiveEntriesSet::iterator it = doomed_entries_.begin();
-  for (; it != doomed_entries_.end() && !found; ++it)
-    found = RemovePendingTransactionFromEntry(*it, trans);
-}
-
-bool HttpCache::RemovePendingTransactionFromEntry(ActiveEntry* entry,
-                                                  Transaction* trans) {
-  TransactionList& pending_queue = entry->pending_queue;
-
-  TransactionList::iterator j =
-      find(pending_queue.begin(), pending_queue.end(), trans);
-  if (j == pending_queue.end())
-    return false;
-
-  pending_queue.erase(j);
-  return true;
-}
-
-void HttpCache::ProcessPendingQueue(ActiveEntry* entry) {
-  // Multiple readers may finish with an entry at once, so we want to batch up
-  // calls to OnProcessPendingQueue.  This flag also tells us that we should
-  // not delete the entry before OnProcessPendingQueue runs.
-  if (entry->will_process_pending_queue)
-    return;
-  entry->will_process_pending_queue = true;
-
-  MessageLoop::current()->PostTask(FROM_HERE,
-      task_factory_.NewRunnableMethod(&HttpCache::OnProcessPendingQueue,
-                                      entry));
-}
-
-void HttpCache::OnProcessPendingQueue(ActiveEntry* entry) {
-  entry->will_process_pending_queue = false;
-  DCHECK(!entry->writer);
-
-  // If no one is interested in this entry, then we can de-activate it.
-  if (entry->pending_queue.empty()) {
-    if (entry->readers.empty())
-      DestroyEntry(entry);
-    return;
-  }
-
-  // Promote next transaction from the pending queue.
-  Transaction* next = entry->pending_queue.front();
-  if ((next->mode() & Transaction::WRITE) && !entry->readers.empty())
-    return;  // Have to wait.
-
-  entry->pending_queue.erase(entry->pending_queue.begin());
-
-  AddTransactionToEntry(entry, next);
-}
-
-void HttpCache::CloseIdleConnections() {
-  net::HttpNetworkLayer* network =
-      static_cast<net::HttpNetworkLayer*>(network_layer_.get());
-  HttpNetworkSession* session = network->GetSession();
-  if (session) {
-    session->tcp_socket_pool()->CloseIdleSockets();
-  }
-}
-
-//-----------------------------------------------------------------------------
-
 }  // namespace net