Panda3D
genericAsyncTask.cxx
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1 /**
2  * PANDA 3D SOFTWARE
3  * Copyright (c) Carnegie Mellon University. All rights reserved.
4  *
5  * All use of this software is subject to the terms of the revised BSD
6  * license. You should have received a copy of this license along
7  * with this source code in a file named "LICENSE."
8  *
9  * @file genericAsyncTask.cxx
10  * @author drose
11  * @date 2008-10-03
12  */
13 
14 #include "genericAsyncTask.h"
15 #include "pnotify.h"
16 
17 TypeHandle GenericAsyncTask::_type_handle;
18 
19 /**
20  *
21  */
22 GenericAsyncTask::
23 GenericAsyncTask(const std::string &name) :
24  AsyncTask(name)
25 {
26  _function = nullptr;
27  _upon_birth = nullptr;
28  _upon_death = nullptr;
29  _user_data = nullptr;
30 }
31 
32 /**
33  *
34  */
35 GenericAsyncTask::
36 GenericAsyncTask(const std::string &name, GenericAsyncTask::TaskFunc *function, void *user_data) :
37  AsyncTask(name),
38  _function(function),
39  _user_data(user_data)
40 {
41  _upon_birth = nullptr;
42  _upon_death = nullptr;
43 }
44 
45 /**
46  * Override this function to return true if the task can be successfully
47  * executed, false if it cannot. Mainly intended as a sanity check when
48  * attempting to add the task to a task manager.
49  *
50  * This function is called with the lock held.
51  */
52 bool GenericAsyncTask::
53 is_runnable() {
54  return _function != nullptr;
55 }
56 
57 /**
58  * Override this function to do something useful for the task.
59  *
60  * This function is called with the lock *not* held.
61  */
62 AsyncTask::DoneStatus GenericAsyncTask::
63 do_task() {
64  nassertr(_function != nullptr, DS_interrupt);
65  return (*_function)(this, _user_data);
66 }
67 
68 /**
69  * Override this function to do something useful when the task has been added
70  * to the active queue.
71  *
72  * This function is called with the lock *not* held.
73  */
74 void GenericAsyncTask::
75 upon_birth(AsyncTaskManager *manager) {
76  AsyncTask::upon_birth(manager);
77 
78  if (_upon_birth != nullptr) {
79  (*_upon_birth)(this, _user_data);
80  }
81 }
82 
83 /**
84  * Override this function to do something useful when the task has been
85  * removed from the active queue. The parameter clean_exit is true if the
86  * task has been removed because it exited normally (returning DS_done), or
87  * false if it was removed for some other reason (e.g.
88  * AsyncTaskManager::remove()). By the time this method is called, _manager
89  * has been cleared, so the parameter manager indicates the original
90  * AsyncTaskManager that owned this task.
91  *
92  * The normal behavior is to throw the done_event only if clean_exit is true.
93  *
94  * This function is called with the lock *not* held.
95  */
96 void GenericAsyncTask::
97 upon_death(AsyncTaskManager *manager, bool clean_exit) {
98  AsyncTask::upon_death(manager, clean_exit);
99 
100  if (_upon_death != nullptr) {
101  (*_upon_death)(this, clean_exit, _user_data);
102  }
103 }
A class to manage a loose queue of isolated tasks, which can be performed either synchronously (in th...
This class represents a concrete task performed by an AsyncManager.
Definition: asyncTask.h:32
TypeHandle is the identifier used to differentiate C++ class types.
Definition: typeHandle.h:81
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.
PANDA 3D SOFTWARE Copyright (c) Carnegie Mellon University.