Reland of Delete unused TaskRunner abstraction.

webrtc/base/task.cc

Index: webrtc/base/task.cc
diff --git a/webrtc/base/task.cc b/webrtc/base/task.cc
deleted file mode 100644
index 1fe3af484089f61f820e6a0b732b5ce10ccb32eb..0000000000000000000000000000000000000000
--- a/webrtc/base/task.cc
+++ /dev/null
@@ -1,283 +0,0 @@
-/*
- *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
- *
- *  Use of this source code is governed by a BSD-style license
- *  that can be found in the LICENSE file in the root of the source
- *  tree. An additional intellectual property rights grant can be found
- *  in the file PATENTS.  All contributing project authors may
- *  be found in the AUTHORS file in the root of the source tree.
- */
-
-#include "webrtc/base/task.h"
-#include "webrtc/base/checks.h"
-#include "webrtc/base/taskrunner.h"
-
-namespace rtc {
-
-int32_t Task::unique_id_seed_ = 0;
-
-Task::Task(TaskParent *parent)
-    : TaskParent(this, parent),
-      state_(STATE_INIT),
-      blocked_(false),
-      done_(false),
-      aborted_(false),
-      busy_(false),
-      error_(false),
-      start_time_(0),
-      timeout_time_(0),
-      timeout_seconds_(0),
-      timeout_suspended_(false)  {
-  unique_id_ = unique_id_seed_++;
-
-  // sanity check that we didn't roll-over our id seed
-  RTC_DCHECK(unique_id_ < unique_id_seed_);
-}
-
-Task::~Task() {
-  // Is this task being deleted in the correct manner?
-#if RTC_DCHECK_IS_ON
-  RTC_DCHECK(!done_ || GetRunner()->is_ok_to_delete(this));
-#endif
-  RTC_DCHECK(state_ == STATE_INIT || done_);
-  RTC_DCHECK(state_ == STATE_INIT || blocked_);
-
-  // If the task is being deleted without being done, it
-  // means that it hasn't been removed from its parent.
-  // This happens if a task is deleted outside of TaskRunner.
-  if (!done_) {
-    Stop();
-  }
-}
-
-int64_t Task::CurrentTime() {
-  return GetRunner()->CurrentTime();
-}
-
-int64_t Task::ElapsedTime() {
-  return CurrentTime() - start_time_;
-}
-
-void Task::Start() {
-  if (state_ != STATE_INIT)
-    return;
-  // Set the start time before starting the task.  Otherwise if the task
-  // finishes quickly and deletes the Task object, setting start_time_
-  // will crash.
-  start_time_ = CurrentTime();
-  GetRunner()->StartTask(this);
-}
-
-void Task::Step() {
-  if (done_) {
-#if RTC_DCHECK_IS_ON
-    // we do not know how !blocked_ happens when done_ - should be impossible.
-    // But it causes problems, so in retail build, we force blocked_, and
-    // under debug we assert.
-    RTC_DCHECK(blocked_);
-#else
-    blocked_ = true;
-#endif
-    return;
-  }
-
-  // Async Error() was called
-  if (error_) {
-    done_ = true;
-    state_ = STATE_ERROR;
-    blocked_ = true;
-//   obsolete - an errored task is not considered done now
-//   SignalDone();
-
-    Stop();
-#if RTC_DCHECK_IS_ON
-    // verify that stop removed this from its parent
-    RTC_DCHECK(!parent()->IsChildTask(this));
-#endif
-    return;
-  }
-
-  busy_ = true;
-  int new_state = Process(state_);
-  busy_ = false;
-
-  if (aborted_) {
-    Abort(true);  // no need to wake because we're awake
-    return;
-  }
-
-  if (new_state == STATE_BLOCKED) {
-    blocked_ = true;
-    // Let the timeout continue
-  } else {
-    state_ = new_state;
-    blocked_ = false;
-    ResetTimeout();
-  }
-
-  if (new_state == STATE_DONE) {
-    done_ = true;
-  } else if (new_state == STATE_ERROR) {
-    done_ = true;
-    error_ = true;
-  }
-
-  if (done_) {
-//  obsolete - call this yourself
-//    SignalDone();
-
-    Stop();
-#if RTC_DCHECK_IS_ON
-    // verify that stop removed this from its parent
-    RTC_DCHECK(!parent()->IsChildTask(this));
-#endif
-    blocked_ = true;
-  }
-}
-
-void Task::Abort(bool nowake) {
-  // Why only check for done_ (instead of "aborted_ || done_")?
-  //
-  // If aborted_ && !done_, it means the logic for aborting still
-  // needs to be executed (because busy_ must have been true when
-  // Abort() was previously called).
-  if (done_)
-    return;
-  aborted_ = true;
-  if (!busy_) {
-    done_ = true;
-    blocked_ = true;
-    error_ = true;
-
-    // "done_" is set before calling "Stop()" to ensure that this code 
-    // doesn't execute more than once (recursively) for the same task.
-    Stop();
-#if RTC_DCHECK_IS_ON
-    // verify that stop removed this from its parent
-    RTC_DCHECK(!parent()->IsChildTask(this));
-#endif
-    if (!nowake) {
-      // WakeTasks to self-delete.
-      // Don't call Wake() because it is a no-op after "done_" is set.
-      // Even if Wake() did run, it clears "blocked_" which isn't desireable.
-      GetRunner()->WakeTasks();
-    }
-  }
-}
-
-void Task::Wake() {
-  if (done_)
-    return;
-  if (blocked_) {
-    blocked_ = false;
-    GetRunner()->WakeTasks();
-  }
-}
-
-void Task::Error() {
-  if (error_ || done_)
-    return;
-  error_ = true;
-  Wake();
-}
-
-std::string Task::GetStateName(int state) const {
-  switch (state) {
-    case STATE_BLOCKED: return "BLOCKED";
-    case STATE_INIT: return "INIT";
-    case STATE_START: return "START";
-    case STATE_DONE: return "DONE";
-    case STATE_ERROR: return "ERROR";
-    case STATE_RESPONSE: return "RESPONSE";
-  }
-  return "??";
-}
-
-int Task::Process(int state) {
-  int newstate = STATE_ERROR;
-
-  if (TimedOut()) {
-    ClearTimeout();
-    newstate = OnTimeout();
-    SignalTimeout();
-  } else {
-    switch (state) {
-      case STATE_INIT:
-        newstate = STATE_START;
-        break;
-      case STATE_START:
-        newstate = ProcessStart();
-        break;
-      case STATE_RESPONSE:
-        newstate = ProcessResponse();
-        break;
-      case STATE_DONE:
-      case STATE_ERROR:
-        newstate = STATE_BLOCKED;
-        break;
-    }
-  }
-
-  return newstate;
-}
-
-void Task::Stop() {
-  // No need to wake because we're either awake or in abort
-  TaskParent::OnStopped(this);
-}
-
-int Task::ProcessResponse() {
-  return STATE_DONE;
-}
-
-void Task::set_timeout_seconds(const int timeout_seconds) {
-  timeout_seconds_ = timeout_seconds;
-  ResetTimeout();
-}
-
-bool Task::TimedOut() {
-  return timeout_seconds_ &&
-    timeout_time_ &&
-    CurrentTime() >= timeout_time_;
-}
-
-void Task::ResetTimeout() {
-  int64_t previous_timeout_time = timeout_time_;
-  bool timeout_allowed = (state_ != STATE_INIT)
-                      && (state_ != STATE_DONE)
-                      && (state_ != STATE_ERROR);
-  if (timeout_seconds_ && timeout_allowed && !timeout_suspended_)
-    timeout_time_ = CurrentTime() +
-                    (timeout_seconds_ * kSecToMsec * kMsecTo100ns);
-  else
-    timeout_time_ = 0;
-
-  GetRunner()->UpdateTaskTimeout(this, previous_timeout_time);
-}
-
-void Task::ClearTimeout() {
-  int64_t previous_timeout_time = timeout_time_;
-  timeout_time_ = 0;
-  GetRunner()->UpdateTaskTimeout(this, previous_timeout_time);
-}
-
-void Task::SuspendTimeout() {
-  if (!timeout_suspended_) {
-    timeout_suspended_ = true;
-    ResetTimeout();
-  }
-}
-
-void Task::ResumeTimeout() {
-  if (timeout_suspended_) {
-    timeout_suspended_ = false;
-    ResetTimeout();
-  }
-}
-
-int Task::OnTimeout() {
-  // by default, we are finished after timing out
-  return STATE_DONE;
-}
-
-} // namespace rtc