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/*
* libjingle
* Copyright 2004--2005, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "task.h"
#include "taskrunner.h"
#include <algorithm>
namespace buzz {
Task::Task(Task * tqparent) :
state_(STATE_INIT),
tqparent_(tqparent),
blocked_(false),
done_(false),
aborted_(false),
busy_(false),
error_(false),
child_error_(false),
start_time_(0) {
runner_ = ((tqparent == NULL) ? (TaskRunner *)this : tqparent->GetRunner());
if (tqparent_ != NULL) {
tqparent_->AddChild(this);
}
}
unsigned long long
Task::CurrentTime() {
return runner_->CurrentTime();
}
unsigned long long
Task::ElapsedTime() {
return CurrentTime() - start_time_;
}
void
Task::Start() {
if (state_ != STATE_INIT)
return;
GetRunner()->StartTask(this);
start_time_ = CurrentTime();
}
void
Task::Step() {
if (done_) {
#ifdef DEBUG
// 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.
assert(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();
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;
}
else {
state_ = new_state;
blocked_ = false;
}
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();
blocked_ = true;
}
}
void
Task::Abort(bool nowake) {
if (aborted_ || done_)
return;
aborted_ = true;
if (!busy_) {
done_ = true;
blocked_ = true;
error_ = true;
Stop();
if (!nowake)
Wake(); // to self-delete
}
}
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 {
static const std::string STR_BLOCKED("BLOCKED");
static const std::string STR_INIT("INIT");
static const std::string STR_START("START");
static const std::string STR_DONE("DONE");
static const std::string STR_ERROR("ERROR");
static const std::string STR_RESPONSE("RESPONSE");
static const std::string STR_HUH("??");
switch (state) {
case STATE_BLOCKED: return STR_BLOCKED;
case STATE_INIT: return STR_INIT;
case STATE_START: return STR_START;
case STATE_DONE: return STR_DONE;
case STATE_ERROR: return STR_ERROR;
case STATE_RESPONSE: return STR_RESPONSE;
}
return STR_HUH;
}
int Task::Process(int state) {
switch (state) {
case STATE_INIT:
return STATE_START;
case STATE_START:
return ProcessStart();
case STATE_RESPONSE:
return ProcessResponse();
case STATE_DONE:
case STATE_ERROR:
return STATE_BLOCKED;
}
return STATE_ERROR;
}
void
Task::AddChild(Task * child) {
tqchildren_.insert(child);
}
bool
Task::AllChildrenDone() {
for (ChildSet::iterator it = tqchildren_.begin(); it != tqchildren_.end(); ++it) {
if (!(*it)->IsDone())
return false;
}
return true;
}
bool
Task::AnyChildError() {
return child_error_;
}
void
Task::AbortAllChildren() {
if (tqchildren_.size() > 0) {
ChildSet copy = tqchildren_;
for (ChildSet::iterator it = copy.begin(); it != copy.end(); ++it) {
(*it)->Abort(true); // Note we do not wake
}
}
}
void
Task::Stop() {
AbortAllChildren(); // No need to wake because we're either awake or in abort
tqparent_->OnChildStopped(this);
}
void
Task::OnChildStopped(Task * child) {
if (child->HasError())
child_error_ = true;
tqchildren_.erase(child);
}
}
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