summaryrefslogtreecommitdiffstats
path: root/src/corelib/statemachine/qstatemachine.cpp
blob: 9cfd25397091d9e197cdf4938a8c0335d67275b8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this
** file. Please review the following information to ensure the GNU Lesser
** General Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of this
** file. Please review the following information to ensure the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qstatemachine.h"

#ifndef QT_NO_STATEMACHINE

#include "qstate.h"
#include "qstate_p.h"
#include "qstatemachine_p.h"
#include "qabstracttransition.h"
#include "qabstracttransition_p.h"
#include "qsignaltransition.h"
#include "qsignaltransition_p.h"
#include "qsignaleventgenerator_p.h"
#include "qabstractstate.h"
#include "qabstractstate_p.h"
#include "qfinalstate.h"
#include "qhistorystate.h"
#include "qhistorystate_p.h"
#include "private/qobject_p.h"
#include "private/qthread_p.h"

#ifndef QT_NO_STATEMACHINE_EVENTFILTER
#include "qeventtransition.h"
#include "qeventtransition_p.h"
#endif

#ifndef QT_NO_ANIMATION
#include "qpropertyanimation.h"
#include "qanimationgroup.h"
#include <private/qvariantanimation_p.h>
#endif

#include <QtCore/qmetaobject.h>
#include <qdebug.h>

QT_BEGIN_NAMESPACE

/*!
    \class QStateMachine
    \reentrant

    \brief The QStateMachine class provides a hierarchical finite state machine.

    \since 4.6
    \ingroup statemachine

    QStateMachine is based on the concepts and notation of
    \l{Statecharts: A visual formalism for complex
    systems}{Statecharts}. QStateMachine is part of \l{The State
    Machine Framework}.

    A state machine manages a set of states (classes that inherit from
    QAbstractState) and transitions (descendants of
    QAbstractTransition) between those states; these states and
    transitions define a state graph. Once a state graph has been
    built, the state machine can execute it. QStateMachine's
    execution algorithm is based on the \l{State Chart XML: State
    Machine Notation for Control Abstraction}{State Chart XML (SCXML)}
    algorithm. The framework's \l{The State Machine
    Framework}{overview} gives several state graphs and the code to
    build them.

    Use the addState() function to add a top-level state to the state machine.
    States are removed with the removeState() function. Removing states while
    the machine is running is discouraged.

    Before the machine can be started, the \l{initialState}{initial
    state} must be set. The initial state is the state that the
    machine enters when started. You can then start() the state
    machine. The started() signal is emitted when the initial state is
    entered.

    The machine is event driven and keeps its own event loop. Events
    are posted to the machine through postEvent(). Note that this
    means that it executes asynchronously, and that it will not
    progress without a running event loop. You will normally not have
    to post events to the machine directly as Qt's transitions, e.g.,
    QEventTransition and its subclasses, handle this. But for custom
    transitions triggered by events, postEvent() is useful.

    The state machine processes events and takes transitions until a
    top-level final state is entered; the state machine then emits the
    finished() signal. You can also stop() the state machine
    explicitly. The stopped() signal is emitted in this case.

    The following snippet shows a state machine that will finish when a button
    is clicked:

    \snippet doc/src/snippets/code/src_corelib_statemachine_qstatemachine.cpp simple state machine

    This code example uses QState, which inherits QAbstractState. The
    QState class provides a state that you can use to set properties
    and invoke methods on \l{QObject}s when the state is entered or
    exited. It also contains convenience functions for adding
    transitions, e.g., \l{QSignalTransition}s as in this example. See
    the QState class description for further details.

    If an error is encountered, the machine will look for an
    \l{errorState}{error state}, and if one is available, it will
    enter this state. The types of errors possible are described by the
    \l{QStateMachine::}{Error} enum. After the error state is entered,
    the type of the error can be retrieved with error(). The execution
    of the state graph will not stop when the error state is entered. If 
    no error state applies to the erroneous state, the machine will stop 
    executing and an error message will be printed to the console.

    \sa QAbstractState, QAbstractTransition, QState, {The State Machine Framework}
*/

/*!
    \property QStateMachine::errorString

    \brief the error string of this state machine
*/

/*!
    \property QStateMachine::globalRestorePolicy

    \brief the restore policy for states of this state machine.

    The default value of this property is
    QStateMachine::DontRestoreProperties.
*/

#ifndef QT_NO_ANIMATION
/*!
    \property QStateMachine::animated

    \brief whether animations are enabled

    The default value of this property is true.

    \sa QAbstractTransition::addAnimation()
*/
#endif

// #define QSTATEMACHINE_DEBUG

QStateMachinePrivate::QStateMachinePrivate()
{
    isMachine = true;

    state = NotRunning;
    _startState = 0;
    processing = false;
    processingScheduled = false;
    stop = false;
    stopProcessingReason = EventQueueEmpty;
    error = QStateMachine::NoError;
    globalRestorePolicy = QStateMachine::DontRestoreProperties;
    signalEventGenerator = 0;
#ifndef QT_NO_ANIMATION
    animated = true;
#endif
}

QStateMachinePrivate::~QStateMachinePrivate()
{
    qDeleteAll(internalEventQueue);
    qDeleteAll(externalEventQueue);
}

QStateMachinePrivate *QStateMachinePrivate::get(QStateMachine *q)
{
    if (q)
        return q->d_func();
    return 0;
}

QState *QStateMachinePrivate::rootState() const
{
    return const_cast<QStateMachine*>(q_func());
}

static QEvent *cloneEvent(QEvent *e)
{
    switch (e->type()) {
    case QEvent::None:
        return new QEvent(*e);
    case QEvent::Timer:
        return new QTimerEvent(*static_cast<QTimerEvent*>(e));
    default:
        Q_ASSERT_X(false, "cloneEvent()", "not implemented");
        break;
    }
    return 0;
}

const QStateMachinePrivate::Handler qt_kernel_statemachine_handler = {
    cloneEvent
};

const QStateMachinePrivate::Handler *QStateMachinePrivate::handler = &qt_kernel_statemachine_handler;

Q_CORE_EXPORT const QStateMachinePrivate::Handler *qcoreStateMachineHandler()
{
    return &qt_kernel_statemachine_handler;
}

static int indexOfDescendant(QState *s, QAbstractState *desc)
{
    QList<QAbstractState*> childStates = QStatePrivate::get(s)->childStates();
    for (int i = 0; i < childStates.size(); ++i) {
        QAbstractState *c = childStates.at(i);
        if ((c == desc) || QStateMachinePrivate::isDescendantOf(desc, c)) {
            return i;
        }
    }
    return -1;
}

bool QStateMachinePrivate::stateEntryLessThan(QAbstractState *s1, QAbstractState *s2)
{
    if (s1->parent() == s2->parent()) {
        return s1->children().indexOf(s1)
            < s2->children().indexOf(s2);
    } else if (isDescendantOf(s1, s2)) {
        return false;
    } else if (isDescendantOf(s2, s1)) {
        return true;
    } else {
        Q_ASSERT(s1->machine() != 0);
        QStateMachinePrivate *mach = QStateMachinePrivate::get(s1->machine());
        QState *lca = mach->findLCA(QList<QAbstractState*>() << s1 << s2);
        Q_ASSERT(lca != 0);
        return (indexOfDescendant(lca, s1) < indexOfDescendant(lca, s2));
    }
}

bool QStateMachinePrivate::stateExitLessThan(QAbstractState *s1, QAbstractState *s2)
{
    if (s1->parent() == s2->parent()) {
        return s1->children().indexOf(s1)
            < s2->children().indexOf(s2);
    } else if (isDescendantOf(s1, s2)) {
        return true;
    } else if (isDescendantOf(s2, s1)) {
        return false;
    } else {
        Q_ASSERT(s1->machine() != 0);
        QStateMachinePrivate *mach = QStateMachinePrivate::get(s1->machine());
        QState *lca = mach->findLCA(QList<QAbstractState*>() << s1 << s2);
        Q_ASSERT(lca != 0);
        return (indexOfDescendant(lca, s1) < indexOfDescendant(lca, s2));
    }
}

QState *QStateMachinePrivate::findLCA(const QList<QAbstractState*> &states) const
{
    if (states.isEmpty())
        return 0;
    QList<QState*> ancestors = properAncestors(states.at(0), rootState()->parentState());
    for (int i = 0; i < ancestors.size(); ++i) {
        QState *anc = ancestors.at(i);
        bool ok = true;
        for (int j = states.size() - 1; (j > 0) && ok; --j) {
            const QAbstractState *s = states.at(j);
            if (!isDescendantOf(s, anc))
                ok = false;
        }
        if (ok)
            return anc;
    }
    return 0;
}

bool QStateMachinePrivate::isPreempted(const QAbstractState *s, const QSet<QAbstractTransition*> &transitions) const
{
    QSet<QAbstractTransition*>::const_iterator it;
    for (it = transitions.constBegin(); it != transitions.constEnd(); ++it) {
        QAbstractTransition *t = *it;
        QList<QAbstractState*> lst = t->targetStates();
        if (!lst.isEmpty()) {
            lst.prepend(t->sourceState());
            QAbstractState *lca = findLCA(lst);
            if (isDescendantOf(s, lca)) {
#ifdef QSTATEMACHINE_DEBUG
                qDebug() << q_func() << ':' << transitions << "preempts selection of a transition from"
                         << s << "because" << s << "is a descendant of" << lca;
#endif
                return true;
            }
        }
    }
    return false;
}

QSet<QAbstractTransition*> QStateMachinePrivate::selectTransitions(QEvent *event) const
{
    Q_Q(const QStateMachine);
    QSet<QAbstractTransition*> enabledTransitions;
    QSet<QAbstractState*>::const_iterator it;
    const_cast<QStateMachine*>(q)->beginSelectTransitions(event);
    for (it = configuration.constBegin(); it != configuration.constEnd(); ++it) {
        QAbstractState *state = *it;
        if (!isAtomic(state))
            continue;
        if (isPreempted(state, enabledTransitions))
            continue;
        QList<QState*> lst = properAncestors(state, rootState()->parentState());
        if (QState *grp = toStandardState(state))
            lst.prepend(grp);
        bool found = false;
        for (int j = 0; (j < lst.size()) && !found; ++j) {
            QState *s = lst.at(j);
            QList<QAbstractTransition*> transitions = QStatePrivate::get(s)->transitions();
            for (int k = 0; k < transitions.size(); ++k) {
                QAbstractTransition *t = transitions.at(k);
                if (QAbstractTransitionPrivate::get(t)->callEventTest(event)) {
#ifdef QSTATEMACHINE_DEBUG
                    qDebug() << q << ": selecting transition" << t;
#endif
                    enabledTransitions.insert(t);
                    found = true;
                    break;
                }
            }
        }
    }
    const_cast<QStateMachine*>(q)->endSelectTransitions(event);
    return enabledTransitions;
}

void QStateMachinePrivate::microstep(QEvent *event, const QList<QAbstractTransition*> &enabledTransitions)
{
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q_func() << ": begin microstep( enabledTransitions:" << enabledTransitions << ')';
    qDebug() << q_func() << ": configuration before exiting states:" << configuration;
#endif
    QList<QAbstractState*> exitedStates = exitStates(event, enabledTransitions);
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q_func() << ": configuration after exiting states:" << configuration;
#endif
    executeTransitionContent(event, enabledTransitions);
    QList<QAbstractState*> enteredStates = enterStates(event, enabledTransitions);
#ifndef QT_NO_PROPERTIES
    applyProperties(enabledTransitions, exitedStates, enteredStates);
#endif
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q_func() << ": configuration after entering states:" << configuration;
    qDebug() << q_func() << ": end microstep";
#endif
}

QList<QAbstractState*> QStateMachinePrivate::exitStates(QEvent *event, const QList<QAbstractTransition*> &enabledTransitions)
{
//    qDebug() << "exitStates(" << enabledTransitions << ')';
    QSet<QAbstractState*> statesToExit;
//    QSet<QAbstractState*> statesToSnapshot;
    for (int i = 0; i < enabledTransitions.size(); ++i) {
        QAbstractTransition *t = enabledTransitions.at(i);
        QList<QAbstractState*> lst = t->targetStates();
        if (lst.isEmpty())
            continue;
        lst.prepend(t->sourceState());
        QAbstractState *lca = findLCA(lst);
        if (lca == 0) {
            setError(QStateMachine::NoCommonAncestorForTransitionError, t->sourceState());
            lst = pendingErrorStates.toList();
            lst.prepend(t->sourceState());
            
            lca = findLCA(lst);
            Q_ASSERT(lca != 0);
        }

        {
            QSet<QAbstractState*>::const_iterator it;
            for (it = configuration.constBegin(); it != configuration.constEnd(); ++it) {
                QAbstractState *s = *it;
                if (isDescendantOf(s, lca))
                    statesToExit.insert(s);
            }
        }
    }
    QList<QAbstractState*> statesToExit_sorted = statesToExit.toList();
    qSort(statesToExit_sorted.begin(), statesToExit_sorted.end(), stateExitLessThan);
    for (int i = 0; i < statesToExit_sorted.size(); ++i) {
        QAbstractState *s = statesToExit_sorted.at(i);
        if (QState *grp = toStandardState(s)) {
            QList<QHistoryState*> hlst = QStatePrivate::get(grp)->historyStates();
            for (int j = 0; j < hlst.size(); ++j) {
                QHistoryState *h = hlst.at(j);
                QHistoryStatePrivate::get(h)->configuration.clear();
                QSet<QAbstractState*>::const_iterator it;
                for (it = configuration.constBegin(); it != configuration.constEnd(); ++it) {
                    QAbstractState *s0 = *it;
                    if (QHistoryStatePrivate::get(h)->historyType == QHistoryState::DeepHistory) {
                        if (isAtomic(s0) && isDescendantOf(s0, s))
                            QHistoryStatePrivate::get(h)->configuration.append(s0);
                    } else if (s0->parentState() == s) {
                        QHistoryStatePrivate::get(h)->configuration.append(s0);
                    }
                }
#ifdef QSTATEMACHINE_DEBUG
                qDebug() << q_func() << ": recorded" << ((QHistoryStatePrivate::get(h)->historyType == QHistoryState::DeepHistory) ? "deep" : "shallow")
                         << "history for" << s << "in" << h << ':' << QHistoryStatePrivate::get(h)->configuration;
#endif
            }
        }
    }
    for (int i = 0; i < statesToExit_sorted.size(); ++i) {
        QAbstractState *s = statesToExit_sorted.at(i);
#ifdef QSTATEMACHINE_DEBUG
        qDebug() << q_func() << ": exiting" << s;
#endif
        QAbstractStatePrivate::get(s)->callOnExit(event);
        configuration.remove(s);
        QAbstractStatePrivate::get(s)->emitExited();
    }
    return statesToExit_sorted;
}

void QStateMachinePrivate::executeTransitionContent(QEvent *event, const QList<QAbstractTransition*> &enabledTransitions)
{
    for (int i = 0; i < enabledTransitions.size(); ++i) {
        QAbstractTransition *t = enabledTransitions.at(i);
#ifdef QSTATEMACHINE_DEBUG
        qDebug() << q_func() << ": triggering" << t;
#endif
        QAbstractTransitionPrivate::get(t)->callOnTransition(event);
        QAbstractTransitionPrivate::get(t)->emitTriggered();
    }
}

QList<QAbstractState*> QStateMachinePrivate::enterStates(QEvent *event, const QList<QAbstractTransition*> &enabledTransitions)
{
#ifdef QSTATEMACHINE_DEBUG
    Q_Q(QStateMachine);
#endif
//    qDebug() << "enterStates(" << enabledTransitions << ')';
    QSet<QAbstractState*> statesToEnter;
    QSet<QAbstractState*> statesForDefaultEntry;

    if (pendingErrorStates.isEmpty()) {
        for (int i = 0; i < enabledTransitions.size(); ++i) {
            QAbstractTransition *t = enabledTransitions.at(i);
            QList<QAbstractState*> lst = t->targetStates();
            if (lst.isEmpty())
                continue;
            lst.prepend(t->sourceState());
            QState *lca = findLCA(lst);
            for (int j = 1; j < lst.size(); ++j) {
                QAbstractState *s = lst.at(j);
			    addStatesToEnter(s, lca, statesToEnter, statesForDefaultEntry);
                if (isParallel(lca)) {
                    QList<QAbstractState*> lcac = QStatePrivate::get(lca)->childStates();
                    foreach (QAbstractState* child,lcac) {
                        if (!statesToEnter.contains(child))
                            addStatesToEnter(child,lca,statesToEnter,statesForDefaultEntry);                    
                    }
                }
            }
        }
    }

    // Did an error occur while selecting transitions? Then we enter the error state.
    if (!pendingErrorStates.isEmpty()) {
        statesToEnter.clear();
        statesToEnter = pendingErrorStates;
        statesForDefaultEntry = pendingErrorStatesForDefaultEntry;
        pendingErrorStates.clear();
        pendingErrorStatesForDefaultEntry.clear();
    }

    QList<QAbstractState*> statesToEnter_sorted = statesToEnter.toList();
    qSort(statesToEnter_sorted.begin(), statesToEnter_sorted.end(), stateEntryLessThan);

    for (int i = 0; i < statesToEnter_sorted.size(); ++i) {
        QAbstractState *s = statesToEnter_sorted.at(i);
#ifdef QSTATEMACHINE_DEBUG
        qDebug() << q << ": entering" << s;
#endif
        configuration.insert(s);
        registerTransitions(s);
        QAbstractStatePrivate::get(s)->callOnEntry(event);
        QAbstractStatePrivate::get(s)->emitEntered();
        if (statesForDefaultEntry.contains(s)) {
            // ### executeContent(s.initial.transition.children())
        }
        if (isFinal(s)) {
            QState *parent = s->parentState();
            if (parent) {
                if (parent != rootState()) {
#ifdef QSTATEMACHINE_DEBUG
                    qDebug() << q << ": emitting finished signal for" << parent;
#endif
                    QStatePrivate::get(parent)->emitFinished();
                }
                QState *grandparent = parent->parentState();
                if (grandparent && isParallel(grandparent)) {
                    bool allChildStatesFinal = true;
                    QList<QAbstractState*> childStates = QStatePrivate::get(grandparent)->childStates();
                    for (int j = 0; j < childStates.size(); ++j) {
                        QAbstractState *cs = childStates.at(j);
                        if (!isInFinalState(cs)) {
                            allChildStatesFinal = false;
                            break;
                        }
                    }
                    if (allChildStatesFinal && (grandparent != rootState())) {
#ifdef QSTATEMACHINE_DEBUG
                        qDebug() << q << ": emitting finished signal for" << grandparent;
#endif
                        QStatePrivate::get(grandparent)->emitFinished();
                    }
                }
            }
        }
    }
    {
        QSet<QAbstractState*>::const_iterator it;
        for (it = configuration.constBegin(); it != configuration.constEnd(); ++it) {
            if (isFinal(*it) && (*it)->parentState() == rootState()) {
                processing = false;
                stopProcessingReason = Finished;
                break;
            }
        }
    }
//    qDebug() << "configuration:" << configuration.toList();
    return statesToEnter_sorted;
}

void QStateMachinePrivate::addStatesToEnter(QAbstractState *s, QState *root,
                                            QSet<QAbstractState*> &statesToEnter,
                                            QSet<QAbstractState*> &statesForDefaultEntry)
{
	if (QHistoryState *h = toHistoryState(s)) {
		QList<QAbstractState*> hconf = QHistoryStatePrivate::get(h)->configuration;
		if (!hconf.isEmpty()) {
			for (int k = 0; k < hconf.size(); ++k) {
				QAbstractState *s0 = hconf.at(k);
				addStatesToEnter(s0, root, statesToEnter, statesForDefaultEntry);
			}
	#ifdef QSTATEMACHINE_DEBUG
			qDebug() <<q_func() << ": restoring"
					<< ((QHistoryStatePrivate::get(h)->historyType == QHistoryState::DeepHistory) ? "deep" : "shallow")
					<< "history from" << s << ':' << hconf;
	#endif
		} else {
			QList<QAbstractState*> hlst;
			if (QHistoryStatePrivate::get(h)->defaultState)
				hlst.append(QHistoryStatePrivate::get(h)->defaultState);

			if (hlst.isEmpty()) {
				setError(QStateMachine::NoDefaultStateInHistoryStateError, h);
			} else {
				for (int k = 0; k < hlst.size(); ++k) {
					QAbstractState *s0 = hlst.at(k);
					addStatesToEnter(s0, root, statesToEnter, statesForDefaultEntry);
				}
	#ifdef QSTATEMACHINE_DEBUG
				qDebug() << q_func() << ": initial history targets for" << s << ':' << hlst;
	#endif
			}
		}
	} else {
            if (s == rootState()) {
                // Error has already been set by exitStates().
                Q_ASSERT(error != QStateMachine::NoError);
                return;
            }
		statesToEnter.insert(s);
		if (isParallel(s)) {
			QState *grp = toStandardState(s);
			QList<QAbstractState*> lst = QStatePrivate::get(grp)->childStates();
			for (int i = 0; i < lst.size(); ++i) {
				QAbstractState *child = lst.at(i);
				addStatesToEnter(child, grp, statesToEnter, statesForDefaultEntry);
			}
		} else if (isCompound(s)) {
			statesForDefaultEntry.insert(s);
			QState *grp = toStandardState(s);
			QAbstractState *initial = grp->initialState();
			if (initial != 0) {
                            Q_ASSERT(initial->machine() == q_func());
				addStatesToEnter(initial, grp, statesToEnter, statesForDefaultEntry);
			} else {
				setError(QStateMachine::NoInitialStateError, grp);
				return;
			}
		}
		QList<QState*> ancs = properAncestors(s, root);
		for (int i = 0; i < ancs.size(); ++i) {
			QState *anc = ancs.at(i);
			if (!anc->parentState())
				continue;
			statesToEnter.insert(anc);
			if (isParallel(anc)) {
				QList<QAbstractState*> lst = QStatePrivate::get(anc)->childStates();
				for (int j = 0; j < lst.size(); ++j) {
					QAbstractState *child = lst.at(j);
					bool hasDescendantInList = false;
					QSet<QAbstractState*>::const_iterator it;
					for (it = statesToEnter.constBegin(); it != statesToEnter.constEnd(); ++it) {
						if (isDescendantOf(*it, child)) {
							hasDescendantInList = true;
							break;
						}
					}
					if (!hasDescendantInList)
						addStatesToEnter(child, anc, statesToEnter, statesForDefaultEntry);
				}
			}
		}
	}
}

#ifndef QT_NO_PROPERTIES

void QStateMachinePrivate::applyProperties(const QList<QAbstractTransition*> &transitionList,
                                           const QList<QAbstractState*> &exitedStates,
                                           const QList<QAbstractState*> &enteredStates)
{
#ifdef QT_NO_ANIMATION
    Q_UNUSED(transitionList);
    Q_UNUSED(exitedStates);
#else
    Q_Q(QStateMachine);
#endif
    // Process the property assignments of the entered states.
    QHash<QAbstractState*, QList<QPropertyAssignment> > propertyAssignmentsForState;
    QHash<RestorableId, QVariant> pendingRestorables = registeredRestorables;
    for (int i = 0; i < enteredStates.size(); ++i) {
        QState *s = toStandardState(enteredStates.at(i));
        if (!s)
            continue;

        QList<QPropertyAssignment> assignments = QStatePrivate::get(s)->propertyAssignments;
        for (int j = 0; j < assignments.size(); ++j) {
            const QPropertyAssignment &assn = assignments.at(j);
            if (globalRestorePolicy == QStateMachine::RestoreProperties) {
                registerRestorable(assn.object, assn.propertyName);
            }
            pendingRestorables.remove(RestorableId(assn.object, assn.propertyName));
            propertyAssignmentsForState[s].append(assn);
        }

        // Remove pending restorables for all parent states to avoid restoring properties
        // before the state that assigned them is exited. If state does not explicitly 
        // assign a property which is assigned by the parent, it inherits the parent's assignment.
        QState *parentState = s;
        while ((parentState = parentState->parentState()) != 0) {
            assignments = QStatePrivate::get(parentState)->propertyAssignments;
            for (int j=0; j<assignments.size(); ++j) {
                const QPropertyAssignment &assn = assignments.at(j);
                int c = pendingRestorables.remove(RestorableId(assn.object, assn.propertyName));
                if (c > 0)
                    propertyAssignmentsForState[s].append(assn);                
            }
        }
    }
    if (!pendingRestorables.isEmpty()) {
        QAbstractState *s;
        if (!enteredStates.isEmpty())
            s = enteredStates.last(); // ### handle if parallel
        else
            s = 0;
        propertyAssignmentsForState[s] << restorablesToPropertyList(pendingRestorables);
    }

#ifndef QT_NO_ANIMATION
    // Gracefully terminate playing animations for states that are exited.
    for (int i = 0; i < exitedStates.size(); ++i) {
        QAbstractState *s = exitedStates.at(i);
        QList<QAbstractAnimation*> animations = animationsForState.take(s);
        for (int j = 0; j < animations.size(); ++j) {
            QAbstractAnimation *anim = animations.at(j);
            QObject::disconnect(anim, SIGNAL(finished()), q, SLOT(_q_animationFinished()));
            stateForAnimation.remove(anim);

            // Stop the (top-level) animation.
            // ### Stopping nested animation has weird behavior.
            QAbstractAnimation *topLevelAnim = anim;
            while (QAnimationGroup *group = topLevelAnim->group())
                topLevelAnim = group;
            topLevelAnim->stop();

            if (resetAnimationEndValues.contains(anim)) {
                qobject_cast<QVariantAnimation*>(anim)->setEndValue(QVariant()); // ### generalize
                resetAnimationEndValues.remove(anim);
            }
            QPropertyAssignment assn = propertyForAnimation.take(anim);
            Q_ASSERT(assn.object != 0);
            // If there is no property assignment that sets this property,
            // set the property to its target value.
            bool found = false;
            QHash<QAbstractState*, QList<QPropertyAssignment> >::const_iterator it;
            for (it = propertyAssignmentsForState.constBegin(); it != propertyAssignmentsForState.constEnd(); ++it) {
                const QList<QPropertyAssignment> &assignments = it.value();
                for (int k = 0; k < assignments.size(); ++k) {
                    if ((assignments.at(k).object == assn.object)
                        && (assignments.at(k).propertyName == assn.propertyName)) {
                        found = true;
                        break;
                    }
                }
            }
            if (!found) {
                assn.object->setProperty(assn.propertyName, assn.value);
            }
        }
    }

    // Find the animations to use for the state change.
    QList<QAbstractAnimation*> selectedAnimations;
    if (animated) {
        for (int i = 0; i < transitionList.size(); ++i) {
            QAbstractTransition *transition = transitionList.at(i);

            selectedAnimations << transition->animations();
            selectedAnimations << defaultAnimationsForSource.values(transition->sourceState());

            QList<QAbstractState *> targetStates = transition->targetStates();
            for (int j=0; j<targetStates.size(); ++j) 
                selectedAnimations << defaultAnimationsForTarget.values(targetStates.at(j));
        }
        selectedAnimations << defaultAnimations;
    }

    // Initialize animations from property assignments.
    for (int i = 0; i < selectedAnimations.size(); ++i) {
        QAbstractAnimation *anim = selectedAnimations.at(i);
        QHash<QAbstractState*, QList<QPropertyAssignment> >::iterator it;
        for (it = propertyAssignmentsForState.begin(); it != propertyAssignmentsForState.end(); ) {
            QList<QPropertyAssignment>::iterator it2;
            QAbstractState *s = it.key();
            QList<QPropertyAssignment> &assignments = it.value();
            for (it2 = assignments.begin(); it2 != assignments.end(); ) {
                QPair<QList<QAbstractAnimation*>, QList<QAbstractAnimation*> > ret;
                ret = initializeAnimation(anim, *it2);
                QList<QAbstractAnimation*> handlers = ret.first;
                if (!handlers.isEmpty()) {
                    for (int j = 0; j < handlers.size(); ++j) {
                        QAbstractAnimation *a = handlers.at(j);
                        propertyForAnimation.insert(a, *it2);
                        stateForAnimation.insert(a, s);
                        animationsForState[s].append(a);
                        // ### connect to just the top-level animation?
                        QObject::connect(a, SIGNAL(finished()), q, SLOT(_q_animationFinished()), Qt::UniqueConnection);
                    }
                    it2 = assignments.erase(it2);
                } else {
                    ++it2;
                }
                for (int j = 0; j < ret.second.size(); ++j)
                    resetAnimationEndValues.insert(ret.second.at(j));
            }
            if (assignments.isEmpty())
                it = propertyAssignmentsForState.erase(it);
            else
                ++it;
        }
        // We require that at least one animation is valid.
        // ### generalize
        QList<QVariantAnimation*> variantAnims = anim->findChildren<QVariantAnimation*>();
        if (QVariantAnimation *va = qobject_cast<QVariantAnimation*>(anim))
            variantAnims.append(va);
        
        bool hasValidEndValue = false;
        for (int j = 0; j < variantAnims.size(); ++j) {
            if (variantAnims.at(j)->endValue().isValid()) {
                hasValidEndValue = true;
                break;
            }
        }

        if (hasValidEndValue) {
            if (anim->state() == QAbstractAnimation::Running) {
                // The animation is still running. This can happen if the
                // animation is a group, and one of its children just finished,
                // and that caused a state to emit its propertiesAssigned() signal, and
                // that triggered a transition in the machine.
                // Just stop the animation so it is correctly restarted again.
                anim->stop();
            }
            anim->start();
        }
    }
#endif // !QT_NO_ANIMATION

    // Immediately set the properties that are not animated.
    {
        QHash<QAbstractState*, QList<QPropertyAssignment> >::const_iterator it;
        for (it = propertyAssignmentsForState.constBegin(); it != propertyAssignmentsForState.constEnd(); ++it) {
            const QList<QPropertyAssignment> &assignments = it.value();
            for (int i = 0; i < assignments.size(); ++i) {
                const QPropertyAssignment &assn = assignments.at(i);
                assn.object->setProperty(assn.propertyName, assn.value);
            }
        }
    }

    // Emit propertiesAssigned signal for entered states that have no animated properties.
    for (int i = 0; i < enteredStates.size(); ++i) {
        QState *s = toStandardState(enteredStates.at(i));
        if (s 
#ifndef QT_NO_ANIMATION
            && !animationsForState.contains(s)
#endif
            )
            QStatePrivate::get(s)->emitPropertiesAssigned();
    }
}

#endif // QT_NO_PROPERTIES

bool QStateMachinePrivate::isFinal(const QAbstractState *s)
{
    return s && (QAbstractStatePrivate::get(s)->stateType == QAbstractStatePrivate::FinalState);
}

bool QStateMachinePrivate::isParallel(const QAbstractState *s)
{
    const QState *ss = toStandardState(s);
    return ss && (QStatePrivate::get(ss)->childMode == QState::ParallelStates);
}

bool QStateMachinePrivate::isCompound(const QAbstractState *s) const
{
    const QState *group = toStandardState(s);
    if (!group)
        return false;
    bool isMachine = QStatePrivate::get(group)->isMachine;
    // Don't treat the machine as compound if it's a sub-state of this machine
    if (isMachine && (group != rootState()))
        return false;
    return (!isParallel(group) && !QStatePrivate::get(group)->childStates().isEmpty())
        || isMachine;
}

bool QStateMachinePrivate::isAtomic(const QAbstractState *s) const
{
    const QState *ss = toStandardState(s);
    return (ss && QStatePrivate::get(ss)->childStates().isEmpty())
        || isFinal(s)
        // Treat the machine as atomic if it's a sub-state of this machine
        || (ss && QStatePrivate::get(ss)->isMachine && (ss != rootState()));
}


bool QStateMachinePrivate::isDescendantOf(const QAbstractState *state, const QAbstractState *other)
{
    Q_ASSERT(state != 0);
    for (QAbstractState *s = state->parentState(); s != 0; s = s->parentState()) {
        if (s == other)
            return true;
    }
    return false;
}

QList<QState*> QStateMachinePrivate::properAncestors(const QAbstractState *state, const QState *upperBound)
{
    Q_ASSERT(state != 0);
    QList<QState*> result;
    for (QState *s = state->parentState(); s && s != upperBound; s = s->parentState()) {
        result.append(s);
    }
    return result;
}

QState *QStateMachinePrivate::toStandardState(QAbstractState *state)
{
    if (state && (QAbstractStatePrivate::get(state)->stateType == QAbstractStatePrivate::StandardState))
        return static_cast<QState*>(state);
    return 0;
}

const QState *QStateMachinePrivate::toStandardState(const QAbstractState *state)
{
    if (state && (QAbstractStatePrivate::get(state)->stateType == QAbstractStatePrivate::StandardState))
        return static_cast<const QState*>(state);
    return 0;
}

QFinalState *QStateMachinePrivate::toFinalState(QAbstractState *state)
{
    if (state && (QAbstractStatePrivate::get(state)->stateType == QAbstractStatePrivate::FinalState))
        return static_cast<QFinalState*>(state);
    return 0;
}

QHistoryState *QStateMachinePrivate::toHistoryState(QAbstractState *state)
{
    if (state && (QAbstractStatePrivate::get(state)->stateType == QAbstractStatePrivate::HistoryState))
        return static_cast<QHistoryState*>(state);
    return 0;
}

bool QStateMachinePrivate::isInFinalState(QAbstractState* s) const
{
    if (isCompound(s)) {
        QState *grp = toStandardState(s);
        QList<QAbstractState*> lst = QStatePrivate::get(grp)->childStates();
        for (int i = 0; i < lst.size(); ++i) {
            QAbstractState *cs = lst.at(i);
            if (isFinal(cs) && configuration.contains(cs))
                return true;
        }
        return false;
    } else if (isParallel(s)) {
        QState *grp = toStandardState(s);
        QList<QAbstractState*> lst = QStatePrivate::get(grp)->childStates();
        for (int i = 0; i < lst.size(); ++i) {
            QAbstractState *cs = lst.at(i);
            if (!isInFinalState(cs))
                return false;
        }
        return true;
    }
    else
        return false;
}

#ifndef QT_NO_PROPERTIES

void QStateMachinePrivate::registerRestorable(QObject *object, const QByteArray &propertyName)
{
    RestorableId id(object, propertyName);
    if (!registeredRestorables.contains(id))
        registeredRestorables.insert(id, object->property(propertyName));
}

QList<QPropertyAssignment> QStateMachinePrivate::restorablesToPropertyList(const QHash<RestorableId, QVariant> &restorables) const
{
    QList<QPropertyAssignment> result;
    QHash<RestorableId, QVariant>::const_iterator it;
    for (it = restorables.constBegin(); it != restorables.constEnd(); ++it) {
//        qDebug() << "restorable:" << it.key().first << it.key().second << it.value();
        result.append(QPropertyAssignment(it.key().first, it.key().second, it.value(), /*explicitlySet=*/false));
    }
    return result;
}

/*! 
   \internal
   Returns true if the variable with the given \a id has been registered for restoration.
*/
bool QStateMachinePrivate::hasRestorable(QObject *object, const QByteArray &propertyName) const
{
    return registeredRestorables.contains(RestorableId(object, propertyName));
}

QVariant QStateMachinePrivate::restorableValue(QObject *object, const QByteArray &propertyName) const
{
    return registeredRestorables.value(RestorableId(object, propertyName), QVariant());
}


/*!
   \internal
    Unregisters the variable identified by \a id
*/
void QStateMachinePrivate::unregisterRestorable(QObject *object, const QByteArray &propertyName)
{
//    qDebug() << "unregisterRestorable(" << object << propertyName << ')';
    RestorableId id(object, propertyName);
    registeredRestorables.remove(id);
}

#endif // QT_NO_PROPERTIES

QAbstractState *QStateMachinePrivate::findErrorState(QAbstractState *context)
{
    // Find error state recursively in parent hierarchy if not set explicitly for context state
    QAbstractState *errorState = 0;
    if (context != 0) {
        QState *s = toStandardState(context);
        if (s != 0)
            errorState = s->errorState();

        if (errorState == 0)
            errorState = findErrorState(context->parentState());
    }
    
    return errorState;   
}

void QStateMachinePrivate::setError(QStateMachine::Error errorCode, QAbstractState *currentContext)
{
    Q_Q(QStateMachine);
    
    error = errorCode;
    switch (errorCode) {
    case QStateMachine::NoInitialStateError:        
        Q_ASSERT(currentContext != 0);

        errorString = QStateMachine::tr("Missing initial state in compound state '%1'")
                        .arg(currentContext->objectName());

        break;
    case QStateMachine::NoDefaultStateInHistoryStateError:
        Q_ASSERT(currentContext != 0);

        errorString = QStateMachine::tr("Missing default state in history state '%1'")
                        .arg(currentContext->objectName());
        break;

    case QStateMachine::NoCommonAncestorForTransitionError:
        Q_ASSERT(currentContext != 0);

        errorString = QStateMachine::tr("No common ancestor for targets and source of transition from state '%1'")
                        .arg(currentContext->objectName());
        break;
    default:
        errorString = QStateMachine::tr("Unknown error");
    };

    pendingErrorStates.clear(); 
    pendingErrorStatesForDefaultEntry.clear();

    QAbstractState *currentErrorState = findErrorState(currentContext);

    // Avoid infinite loop if the error state itself has an error
    if (currentContext == currentErrorState)
        currentErrorState = 0;    

    Q_ASSERT(currentErrorState != rootState());

    if (currentErrorState != 0) {    
        QState *lca = findLCA(QList<QAbstractState*>() << currentErrorState << currentContext);
        addStatesToEnter(currentErrorState, lca, pendingErrorStates, pendingErrorStatesForDefaultEntry);
    } else {
        qWarning("Unrecoverable error detected in running state machine: %s", 
                 qPrintable(errorString));
        q->stop();
    }
}

#ifndef QT_NO_ANIMATION

QPair<QList<QAbstractAnimation*>, QList<QAbstractAnimation*> >
QStateMachinePrivate::initializeAnimation(QAbstractAnimation *abstractAnimation, 
                                          const QPropertyAssignment &prop)
{
    QList<QAbstractAnimation*> handledAnimations;
    QList<QAbstractAnimation*> localResetEndValues;
    QAnimationGroup *group = qobject_cast<QAnimationGroup*>(abstractAnimation);
    if (group) {
        for (int i = 0; i < group->animationCount(); ++i) {
            QAbstractAnimation *animationChild = group->animationAt(i);
            QPair<QList<QAbstractAnimation*>, QList<QAbstractAnimation*> > ret;
            ret = initializeAnimation(animationChild, prop);
            handledAnimations << ret.first;
            localResetEndValues << ret.second;
        }
    } else { 
        QPropertyAnimation *animation = qobject_cast<QPropertyAnimation *>(abstractAnimation);
        if (animation != 0 
            && prop.object == animation->targetObject()
            && prop.propertyName == animation->propertyName()) {

            // Only change end value if it is undefined
            if (!animation->endValue().isValid()) {
                animation->setEndValue(prop.value);
                localResetEndValues.append(animation);
            }
            handledAnimations.append(animation);
        }
    }
    return qMakePair(handledAnimations, localResetEndValues);
}

void QStateMachinePrivate::_q_animationFinished()
{
    Q_Q(QStateMachine);
    QAbstractAnimation *anim = qobject_cast<QAbstractAnimation*>(q->sender());
    Q_ASSERT(anim != 0);
    QObject::disconnect(anim, SIGNAL(finished()), q, SLOT(_q_animationFinished()));
    if (resetAnimationEndValues.contains(anim)) {
        qobject_cast<QVariantAnimation*>(anim)->setEndValue(QVariant()); // ### generalize
        resetAnimationEndValues.remove(anim);
    }

#ifndef QT_NO_PROPERTIES
    // Set the final property value.
    QPropertyAssignment assn = propertyForAnimation.take(anim);
    Q_ASSERT(assn.object != 0);
    assn.object->setProperty(assn.propertyName, assn.value);
    if (!assn.explicitlySet)
        unregisterRestorable(assn.object, assn.propertyName);
#endif

    QAbstractState *state = stateForAnimation.take(anim);
    Q_ASSERT(state != 0);
    QHash<QAbstractState*, QList<QAbstractAnimation*> >::iterator it;
    it = animationsForState.find(state);
    Q_ASSERT(it != animationsForState.end());
    QList<QAbstractAnimation*> &animations = it.value();
    animations.removeOne(anim);
    if (animations.isEmpty()) {
        animationsForState.erase(it);
        QStatePrivate::get(toStandardState(state))->emitPropertiesAssigned();
    }
}

#endif // !QT_NO_ANIMATION

namespace {

class StartState : public QState
{
public:
    StartState(QState *parent)
        : QState(parent) {}
protected:
    void onEntry(QEvent *) {}
    void onExit(QEvent *) {}
};

class InitialTransition : public QAbstractTransition
{
public:
    InitialTransition(QAbstractState *target)
        : QAbstractTransition()
    { setTargetState(target); }
protected:
    virtual bool eventTest(QEvent *) { return true; }
    virtual void onTransition(QEvent *) {}
};

} // namespace

QState *QStateMachinePrivate::startState()
{
    Q_Q(QStateMachine);
    if (_startState == 0)
        _startState = new StartState(q);
    return _startState;
}

void QStateMachinePrivate::removeStartState()
{
    delete _startState;
    _startState = 0;
}

void QStateMachinePrivate::clearHistory()
{
    Q_Q(QStateMachine);
    QList<QHistoryState*> historyStates = q->findChildren<QHistoryState*>();
    for (int i = 0; i < historyStates.size(); ++i) {
        QHistoryState *h = historyStates.at(i);
        QHistoryStatePrivate::get(h)->configuration.clear();
    }
}

void QStateMachinePrivate::_q_start()
{
    Q_Q(QStateMachine);
    Q_ASSERT(state == Starting);
    Q_ASSERT(rootState() != 0);
    QAbstractState *initial = rootState()->initialState();
    configuration.clear();
    qDeleteAll(internalEventQueue);
    internalEventQueue.clear();
    qDeleteAll(externalEventQueue);
    externalEventQueue.clear();
    clearHistory();

#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": starting";
#endif
    state = Running;
    processingScheduled = true; // we call _q_process() below
    emit q->started();

    QState *start = startState();
    Q_ASSERT(start != 0);

    QList<QAbstractTransition*> transitions = QStatePrivate::get(start)->transitions();

    // If a transition has already been added, then we skip this step, as the
    // initial transition in that case has been overridden.
    if (transitions.isEmpty()) {
        QAbstractTransition *initialTransition = new InitialTransition(initial);
        start->addTransition(initialTransition);
        transitions.append(initialTransition);
    }

    QEvent nullEvent(QEvent::None);
    executeTransitionContent(&nullEvent, transitions);
    QList<QAbstractState*> enteredStates = enterStates(&nullEvent, transitions);
#ifndef QT_NO_PROPERTIES
    applyProperties(transitions, QList<QAbstractState*>() << start,
                    enteredStates);
#endif
    removeStartState();

#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": initial configuration:" << configuration;
#endif
    _q_process();
}

void QStateMachinePrivate::_q_process()
{
    Q_Q(QStateMachine);
    Q_ASSERT(state == Running);
    Q_ASSERT(!processing);
    processing = true;
    processingScheduled = false;
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": starting the event processing loop";
#endif
    while (processing) {
        if (stop) {
            processing = false;
            break;
        }
        QSet<QAbstractTransition*> enabledTransitions;
        QEvent *e = new QEvent(QEvent::None);
        enabledTransitions = selectTransitions(e);
        if (enabledTransitions.isEmpty()) {
            delete e;
            e = 0;
        }
        if (enabledTransitions.isEmpty() && ((e = dequeueInternalEvent()) != 0)) {
#ifdef QSTATEMACHINE_DEBUG
            qDebug() << q << ": dequeued internal event" << e << "of type" << e->type();
#endif
            enabledTransitions = selectTransitions(e);
            if (enabledTransitions.isEmpty()) {
                delete e;
                e = 0;
            }
        }
        if (enabledTransitions.isEmpty()) {
            if ((e = dequeueExternalEvent()) != 0) {
#ifdef QSTATEMACHINE_DEBUG
                qDebug() << q << ": dequeued external event" << e << "of type" << e->type();
#endif
                enabledTransitions = selectTransitions(e);
                if (enabledTransitions.isEmpty()) {
                    delete e;
                    e = 0;
                }
            } else {
                if (isInternalEventQueueEmpty()) {
                    processing = false;
                    stopProcessingReason = EventQueueEmpty;
                }
            }
        }
        if (!enabledTransitions.isEmpty()) {
            q->beginMicrostep(e);
            microstep(e, enabledTransitions.toList());
            q->endMicrostep(e);
        }
#ifdef QSTATEMACHINE_DEBUG
        else {
            qDebug() << q << ": no transitions enabled";
        }
#endif
        delete e;
    }
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": finished the event processing loop";
#endif
    if (stop) {
        stop = false;
        stopProcessingReason = Stopped;
    }

    switch (stopProcessingReason) {
    case EventQueueEmpty:
        break;
    case Finished:
        state = NotRunning;
        cancelAllDelayedEvents();
        unregisterAllTransitions();
        emit q->finished();
        break;
    case Stopped:
        state = NotRunning;
        cancelAllDelayedEvents();
        unregisterAllTransitions();
        emit q->stopped();
        break;
    }
}

void QStateMachinePrivate::postInternalEvent(QEvent *e)
{
    QMutexLocker locker(&internalEventMutex);
    internalEventQueue.append(e);
}

void QStateMachinePrivate::postExternalEvent(QEvent *e)
{
    QMutexLocker locker(&externalEventMutex);
    externalEventQueue.append(e);
}

QEvent *QStateMachinePrivate::dequeueInternalEvent()
{
    QMutexLocker locker(&internalEventMutex);
    if (internalEventQueue.isEmpty())
        return 0;
    return internalEventQueue.takeFirst();
}

QEvent *QStateMachinePrivate::dequeueExternalEvent()
{
    QMutexLocker locker(&externalEventMutex);
    if (externalEventQueue.isEmpty())
        return 0;
    return externalEventQueue.takeFirst();
}

bool QStateMachinePrivate::isInternalEventQueueEmpty()
{
    QMutexLocker locker(&internalEventMutex);
    return internalEventQueue.isEmpty();
}

bool QStateMachinePrivate::isExternalEventQueueEmpty()
{
    QMutexLocker locker(&externalEventMutex);
    return externalEventQueue.isEmpty();
}

void QStateMachinePrivate::processEvents(EventProcessingMode processingMode)
{
    Q_Q(QStateMachine);
    if ((state != Running) || processing || processingScheduled)
        return;
    switch (processingMode) {
    case DirectProcessing:
        if (QThread::currentThread() == q->thread()) {
            _q_process();
            break;
        } // fallthrough -- processing must be done in the machine thread
    case QueuedProcessing:
        processingScheduled = true;
        QMetaObject::invokeMethod(q, "_q_process", Qt::QueuedConnection);
        break;
    }
}

void QStateMachinePrivate::cancelAllDelayedEvents()
{
    Q_Q(QStateMachine);
    QMutexLocker locker(&delayedEventsMutex);
    QHash<int, QEvent*>::const_iterator it;
    for (it = delayedEvents.constBegin(); it != delayedEvents.constEnd(); ++it) {
        int id = it.key();
        QEvent *e = it.value();
        q->killTimer(id);
        delete e;
    }
    delayedEvents.clear();
}

namespace _QStateMachine_Internal{

class GoToStateTransition : public QAbstractTransition
{
public:
    GoToStateTransition(QAbstractState *target)
        : QAbstractTransition()
    { setTargetState(target); }
protected:
    void onTransition(QEvent *) { deleteLater(); }
    bool eventTest(QEvent *) { return true; }
};

} // namespace
// mingw compiler tries to export QObject::findChild<GoToStateTransition>(),
// which doesn't work if its in an anonymous namespace.
using namespace _QStateMachine_Internal;
/*!
  \internal

  Causes this state machine to unconditionally transition to the given
  \a targetState.

  Provides a backdoor for using the state machine "imperatively"; i.e.  rather
  than defining explicit transitions, you drive the machine's execution by
  calling this function. It breaks the whole integrity of the
  transition-driven model, but is provided for pragmatic reasons.
*/
void QStateMachinePrivate::goToState(QAbstractState *targetState)
{
    if (!targetState) {
        qWarning("QStateMachine::goToState(): cannot go to null state");
        return;
    }

    if (configuration.contains(targetState))
        return;

    QState *sourceState = 0;
    if (state == Running) {
        QSet<QAbstractState*>::const_iterator it;
        for (it = configuration.constBegin(); it != configuration.constEnd(); ++it) {
            sourceState = toStandardState(*it);
            if (sourceState != 0)
                break;
        }
    } else {
        sourceState = startState();
    }    

    Q_ASSERT(sourceState != 0);
    // Reuse previous GoToStateTransition in case of several calls to
    // goToState() in a row.
    GoToStateTransition *trans = sourceState->findChild<GoToStateTransition*>();
    if (!trans) {
        trans = new GoToStateTransition(targetState);
        sourceState->addTransition(trans);
    } else {
        trans->setTargetState(targetState);
    }

    processEvents(QueuedProcessing);
}

void QStateMachinePrivate::registerTransitions(QAbstractState *state)
{
    QState *group = toStandardState(state);
    if (!group)
        return;
    QList<QAbstractTransition*> transitions = QStatePrivate::get(group)->transitions();
    for (int i = 0; i < transitions.size(); ++i) {
        QAbstractTransition *t = transitions.at(i);
        if (QSignalTransition *st = qobject_cast<QSignalTransition*>(t)) {
            registerSignalTransition(st);
        }
#ifndef QT_NO_STATEMACHINE_EVENTFILTER
        else if (QEventTransition *oet = qobject_cast<QEventTransition*>(t)) {
            registerEventTransition(oet);
        }
#endif
    }
}

void QStateMachinePrivate::unregisterTransition(QAbstractTransition *transition)
{
    if (QSignalTransition *st = qobject_cast<QSignalTransition*>(transition)) {
        unregisterSignalTransition(st);
    }
#ifndef QT_NO_STATEMACHINE_EVENTFILTER
    else if (QEventTransition *oet = qobject_cast<QEventTransition*>(transition)) {
        unregisterEventTransition(oet);
    }
#endif
}

void QStateMachinePrivate::registerSignalTransition(QSignalTransition *transition)
{
    Q_Q(QStateMachine);
    if (QSignalTransitionPrivate::get(transition)->signalIndex != -1)
        return; // already registered
    QObject *sender = QSignalTransitionPrivate::get(transition)->sender;
    if (!sender)
        return;
    QByteArray signal = QSignalTransitionPrivate::get(transition)->signal;
    if (signal.startsWith('0'+QSIGNAL_CODE))
        signal.remove(0, 1);
    const QMetaObject *meta = sender->metaObject();
    int signalIndex = meta->indexOfSignal(signal);
    int originalSignalIndex = signalIndex;
    if (signalIndex == -1) {
        signalIndex = meta->indexOfSignal(QMetaObject::normalizedSignature(signal));
        if (signalIndex == -1) {
            qWarning("QSignalTransition: no such signal: %s::%s",
                     meta->className(), signal.constData());
            return;
        }
    }
    // The signal index we actually want to connect to is the one
    // that is going to be sent, i.e. the non-cloned original index.
    while (meta->method(signalIndex).attributes() & QMetaMethod::Cloned)
        --signalIndex;

    QVector<int> &connectedSignalIndexes = connections[sender];
    if (connectedSignalIndexes.size() <= signalIndex)
        connectedSignalIndexes.resize(signalIndex+1);
    if (connectedSignalIndexes.at(signalIndex) == 0) {
        if (!signalEventGenerator)
            signalEventGenerator = new QSignalEventGenerator(q);
        bool ok = QMetaObject::connect(sender, signalIndex, signalEventGenerator,
                                       signalEventGenerator->metaObject()->methodOffset());
        if (!ok) {
#ifdef QSTATEMACHINE_DEBUG
            qDebug() << q << ": FAILED to add signal transition from" << transition->sourceState()
                     << ": ( sender =" << sender << ", signal =" << signal
                     << ", targets =" << transition->targetStates() << ')';
#endif
            return;
        }
    }
    ++connectedSignalIndexes[signalIndex];
    QSignalTransitionPrivate::get(transition)->signalIndex = signalIndex;
    QSignalTransitionPrivate::get(transition)->originalSignalIndex = originalSignalIndex;
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": added signal transition from" << transition->sourceState()
             << ": ( sender =" << sender << ", signal =" << signal
             << ", targets =" << transition->targetStates() << ')';
#endif
}

void QStateMachinePrivate::unregisterSignalTransition(QSignalTransition *transition)
{
    int signalIndex = QSignalTransitionPrivate::get(transition)->signalIndex;
    if (signalIndex == -1)
        return; // not registered
    QSignalTransitionPrivate::get(transition)->signalIndex = -1;
    const QObject *sender = QSignalTransitionPrivate::get(transition)->sender;
    QVector<int> &connectedSignalIndexes = connections[sender];
    Q_ASSERT(connectedSignalIndexes.size() > signalIndex);
    Q_ASSERT(connectedSignalIndexes.at(signalIndex) != 0);
    if (--connectedSignalIndexes[signalIndex] == 0) {
        Q_ASSERT(signalEventGenerator != 0);
        QMetaObject::disconnect(sender, signalIndex, signalEventGenerator,
                                signalEventGenerator->metaObject()->methodOffset());
        int sum = 0;
        for (int i = 0; i < connectedSignalIndexes.size(); ++i)
            sum += connectedSignalIndexes.at(i);
        if (sum == 0)
            connections.remove(sender);
    }
}

void QStateMachinePrivate::unregisterAllTransitions()
{
    Q_Q(QStateMachine);
    {
        QList<QSignalTransition*> transitions = rootState()->findChildren<QSignalTransition*>();
        for (int i = 0; i < transitions.size(); ++i) {
            QSignalTransition *t = transitions.at(i);
            if (t->machine() == q)
                unregisterSignalTransition(t);
        }
    }
    {
        QList<QEventTransition*> transitions = rootState()->findChildren<QEventTransition*>();
        for (int i = 0; i < transitions.size(); ++i) {
            QEventTransition *t = transitions.at(i);
            if (t->machine() == q)
                unregisterEventTransition(t);
        }
    }
}

#ifndef QT_NO_STATEMACHINE_EVENTFILTER
void QStateMachinePrivate::registerEventTransition(QEventTransition *transition)
{
    Q_Q(QStateMachine);
    if (QEventTransitionPrivate::get(transition)->registered)
        return;
    if (transition->eventType() >= QEvent::User) {
        qWarning("QObject event transitions are not supported for custom types");
        return;
    }
    QObject *object = QEventTransitionPrivate::get(transition)->object;
    if (!object)
        return;
    QObjectPrivate *od = QObjectPrivate::get(object);
    if (!od->eventFilters.contains(q))
        object->installEventFilter(q);
    ++qobjectEvents[object][transition->eventType()];
    QEventTransitionPrivate::get(transition)->registered = true;
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q << ": added event transition from" << transition->sourceState()
             << ": ( object =" << object << ", event =" << transition->eventType()
             << ", targets =" << transition->targetStates() << ')';
#endif
}

void QStateMachinePrivate::unregisterEventTransition(QEventTransition *transition)
{
    Q_Q(QStateMachine);
    if (!QEventTransitionPrivate::get(transition)->registered)
        return;
    QObject *object = QEventTransitionPrivate::get(transition)->object;
    QHash<QEvent::Type, int> &events = qobjectEvents[object];
    Q_ASSERT(events.value(transition->eventType()) > 0);
    if (--events[transition->eventType()] == 0) {
        events.remove(transition->eventType());
        int sum = 0;
        QHash<QEvent::Type, int>::const_iterator it;
        for (it = events.constBegin(); it != events.constEnd(); ++it)
            sum += it.value();
        if (sum == 0) {
            qobjectEvents.remove(object);
            object->removeEventFilter(q);
        }
    }
    QEventTransitionPrivate::get(transition)->registered = false;
}

void QStateMachinePrivate::handleFilteredEvent(QObject *watched, QEvent *event)
{    
    if (qobjectEvents.value(watched).contains(event->type())) {
        postInternalEvent(new QStateMachine::WrappedEvent(watched, handler->cloneEvent(event)));
        processEvents(DirectProcessing);
    }
}
#endif

void QStateMachinePrivate::handleTransitionSignal(QObject *sender, int signalIndex,
                                                  void **argv)
{
    Q_ASSERT(connections[sender].at(signalIndex) != 0);
    const QMetaObject *meta = sender->metaObject();
    QMetaMethod method = meta->method(signalIndex);
    QList<QByteArray> parameterTypes = method.parameterTypes();
    int argc = parameterTypes.count();
    QList<QVariant> vargs;
    for (int i = 0; i < argc; ++i) {
        int type = QMetaType::type(parameterTypes.at(i));
        vargs.append(QVariant(type, argv[i+1]));
    }

#ifdef QSTATEMACHINE_DEBUG
    qDebug() << q_func() << ": sending signal event ( sender =" << sender
             << ", signal =" << sender->metaObject()->method(signalIndex).signature() << ')';
#endif
    postInternalEvent(new QStateMachine::SignalEvent(sender, signalIndex, vargs));
    processEvents(DirectProcessing);
}

/*!
  Constructs a new state machine with the given \a parent.
*/
QStateMachine::QStateMachine(QObject *parent)
    : QState(*new QStateMachinePrivate, /*parentState=*/0)
{
    // Can't pass the parent to the QState constructor, as it expects a QState
    // But this works as expected regardless of whether parent is a QState or not
    setParent(parent);
}

/*!
  \internal
*/
QStateMachine::QStateMachine(QStateMachinePrivate &dd, QObject *parent)
    : QState(dd, /*parentState=*/0)
{
    setParent(parent);
}

/*!
  Destroys this state machine.
*/
QStateMachine::~QStateMachine()
{
}

/*!
  \enum QStateMachine::EventPriority

  This enum type specifies the priority of an event posted to the state
  machine using postEvent().

  Events of high priority are processed before events of normal priority.

  \value NormalPriority The event has normal priority.
  \value HighPriority The event has high priority.
*/

/*! \enum QStateMachine::Error 

    This enum type defines errors that can occur in the state machine at run time. When the state
    machine encounters an unrecoverable error at run time, it will set the error code returned 
    by error(), the error message returned by errorString(), and enter an error state based on 
    the context of the error.

    \value NoError No error has occurred.
    \value NoInitialStateError The machine has entered a QState with children which does not have an
           initial state set. The context of this error is the state which is missing an initial
           state.
    \value NoDefaultStateInHistoryStateError The machine has entered a QHistoryState which does not have 
           a default state set. The context of this error is the QHistoryState which is missing a
           default state.
    \value NoCommonAncestorForTransitionError The machine has selected a transition whose source 
           and targets are not part of the same tree of states, and thus are not part of the same 
           state machine. Commonly, this could mean that one of the states has not been given 
           any parent or added to any machine. The context of this error is the source state of 
           the transition.

    \sa setErrorState()
*/

/*!
   \enum QStateMachine::RestorePolicy

   This enum specifies the restore policy type. The restore policy
   takes effect when the machine enters a state which sets one or more
   properties. If the restore policy is set to RestoreProperties,
   the state machine will save the original value of the property before the
   new value is set.

   Later, when the machine either enters a state which does not set
   a value for the given property, the property will automatically be restored
   to its initial value.

   Only one initial value will be saved for any given property. If a value for a property has 
   already been saved by the state machine, it will not be overwritten until the property has been
   successfully restored. 

   \value DontRestoreProperties The state machine should not save the initial values of properties
          and restore them later.
   \value RestoreProperties The state machine should save the initial values of properties 
          and restore them later.

   \sa QStateMachine::globalRestorePolicy QState::assignProperty()
*/


/*!
  Returns the error code of the last error that occurred in the state machine.
*/
QStateMachine::Error QStateMachine::error() const
{
    Q_D(const QStateMachine);
    return d->error;
}

/*!
  Returns the error string of the last error that occurred in the state machine.
*/
QString QStateMachine::errorString() const
{
    Q_D(const QStateMachine);
    return d->errorString;
}

/*!
  Clears the error string and error code of the state machine.
*/
void QStateMachine::clearError()
{
    Q_D(QStateMachine);
    d->errorString.clear();
    d->error = NoError;
}

/*!
   Returns the restore policy of the state machine.

   \sa setGlobalRestorePolicy()
*/
QStateMachine::RestorePolicy QStateMachine::globalRestorePolicy() const
{
    Q_D(const QStateMachine);
    return d->globalRestorePolicy;
}

/*!
   Sets the restore policy of the state machine to \a restorePolicy. The default 
   restore policy is QAbstractState::DontRestoreProperties.
   
   \sa globalRestorePolicy()
*/
void QStateMachine::setGlobalRestorePolicy(QStateMachine::RestorePolicy restorePolicy) 
{
    Q_D(QStateMachine);
    d->globalRestorePolicy = restorePolicy;
}

/*!
  Adds the given \a state to this state machine. The state becomes a top-level
  state.

  If the state is already in a different machine, it will first be removed
  from its old machine, and then added to this machine.

  \sa removeState(), setInitialState()
*/
void QStateMachine::addState(QAbstractState *state)
{
    if (!state) {
        qWarning("QStateMachine::addState: cannot add null state");
        return;
    }
    if (QAbstractStatePrivate::get(state)->machine() == this) {
        qWarning("QStateMachine::addState: state has already been added to this machine");
        return;
    }
    state->setParent(this);
}

/*!
  Removes the given \a state from this state machine.  The state machine
  releases ownership of the state.

  \sa addState()
*/
void QStateMachine::removeState(QAbstractState *state)
{
    if (!state) {
        qWarning("QStateMachine::removeState: cannot remove null state");
        return;
    }
    if (QAbstractStatePrivate::get(state)->machine() != this) {
        qWarning("QStateMachine::removeState: state %p's machine (%p)"
                 " is different from this machine (%p)",
                 state, QAbstractStatePrivate::get(state)->machine(), this);
        return;
    }
    state->setParent(0);
}

/*!
  Returns whether this state machine is running.

  start(), stop()
*/
bool QStateMachine::isRunning() const
{
    Q_D(const QStateMachine);
    return (d->state == QStateMachinePrivate::Running);
}

/*!
  Starts this state machine.  The machine will reset its configuration and
  transition to the initial state.  When a final top-level state (QFinalState)
  is entered, the machine will emit the finished() signal.

  \note A state machine will not run without a running event loop, such as
  the main application event loop started with QCoreApplication::exec() or
  QApplication::exec().

  \sa started(), finished(), stop(), initialState()
*/
void QStateMachine::start()
{
    Q_D(QStateMachine);

    if (initialState() == 0) {
        qWarning("QStateMachine::start: No initial state set for machine. Refusing to start.");
        return;
    }

    switch (d->state) {
    case QStateMachinePrivate::NotRunning:
        d->state = QStateMachinePrivate::Starting;
        QMetaObject::invokeMethod(this, "_q_start", Qt::QueuedConnection);
        break;
    case QStateMachinePrivate::Starting:
        break;
    case QStateMachinePrivate::Running:
        qWarning("QStateMachine::start(): already running");
        break;
    }
}

/*!
  Stops this state machine. The state machine will stop processing events and
  then emit the stopped() signal.

  \sa stopped(), start()
*/
void QStateMachine::stop()
{
    Q_D(QStateMachine);
    switch (d->state) {
    case QStateMachinePrivate::NotRunning:
        break;
    case QStateMachinePrivate::Starting:
        // the machine will exit as soon as it enters the event processing loop
        d->stop = true;
        break;
    case QStateMachinePrivate::Running:
        d->stop = true;
        d->processEvents(QStateMachinePrivate::QueuedProcessing);
        break;
    }
}

/*!
  \threadsafe

  Posts the given \a event of the given \a priority for processing by this
  state machine.

  This function returns immediately. The event is added to the state machine's
  event queue. Events are processed in the order posted. The state machine
  takes ownership of the event and deletes it once it has been processed.

  You can only post events when the state machine is running.

  \sa postDelayedEvent()
*/
void QStateMachine::postEvent(QEvent *event, EventPriority priority)
{
    Q_D(QStateMachine);
    if (d->state != QStateMachinePrivate::Running) {
        qWarning("QStateMachine::postEvent: cannot post event when the state machine is not running");
        return;
    }
    if (!event) {
        qWarning("QStateMachine::postEvent: cannot post null event");
        return;
    }
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << this << ": posting event" << event;
#endif
    switch (priority) {
    case NormalPriority:
        d->postExternalEvent(event);
        break;
    case HighPriority:
        d->postInternalEvent(event);
        break;
    }
    d->processEvents(QStateMachinePrivate::QueuedProcessing);
}

/*!
  \threadsafe

  Posts the given \a event for processing by this state machine, with the
  given \a delay in milliseconds. Returns an identifier associated with the
  delayed event, or -1 if the event could not be posted.

  This function returns immediately. When the delay has expired, the event
  will be added to the state machine's event queue for processing. The state
  machine takes ownership of the event and deletes it once it has been
  processed.

  You can only post events when the state machine is running.

  \sa cancelDelayedEvent(), postEvent()
*/
int QStateMachine::postDelayedEvent(QEvent *event, int delay)
{
    Q_D(QStateMachine);
    if (d->state != QStateMachinePrivate::Running) {
        qWarning("QStateMachine::postDelayedEvent: cannot post event when the state machine is not running");
        return -1;
    }
    if (!event) {
        qWarning("QStateMachine::postDelayedEvent: cannot post null event");
        return -1;
    }
    if (delay < 0) {
        qWarning("QStateMachine::postDelayedEvent: delay cannot be negative");
        return -1;
    }
#ifdef QSTATEMACHINE_DEBUG
    qDebug() << this << ": posting event" << event << "with delay" << delay;
#endif
    QMutexLocker locker(&d->delayedEventsMutex);
    int tid = startTimer(delay);
    d->delayedEvents[tid] = event;
    return tid;
}

/*!
  \threadsafe

  Cancels the delayed event identified by the given \a id. The id should be a
  value returned by a call to postDelayedEvent(). Returns true if the event
  was successfully cancelled, otherwise returns false.

  \sa postDelayedEvent()
*/
bool QStateMachine::cancelDelayedEvent(int id)
{
    Q_D(QStateMachine);
    if (d->state != QStateMachinePrivate::Running) {
        qWarning("QStateMachine::cancelDelayedEvent: the machine is not running");
        return false;
    }
    QMutexLocker locker(&d->delayedEventsMutex);
    QEvent *e = d->delayedEvents.take(id);
    if (!e)
        return false;
    killTimer(id);
    delete e;
    return true;
}

/*!
   Returns the maximal consistent set of states (including parallel and final
   states) that this state machine is currently in. If a state \c s is in the
   configuration, it is always the case that the parent of \c s is also in
   c. Note, however, that the machine itself is not an explicit member of the
   configuration.
*/
QSet<QAbstractState*> QStateMachine::configuration() const
{
    Q_D(const QStateMachine);
    return d->configuration;
}

/*!
  \fn QStateMachine::started()

  This signal is emitted when the state machine has entered its initial state
  (QStateMachine::initialState).

  \sa QStateMachine::finished(), QStateMachine::start()
*/

/*!
  \fn QStateMachine::stopped()

  This signal is emitted when the state machine has stopped.

  \sa QStateMachine::stop(), QStateMachine::finished()
*/

/*!
  \reimp
*/
bool QStateMachine::event(QEvent *e)
{
    Q_D(QStateMachine);
    if (e->type() == QEvent::Timer) {
        QTimerEvent *te = static_cast<QTimerEvent*>(e);
        int tid = te->timerId();
        if (d->state != QStateMachinePrivate::Running) {
            // This event has been cancelled already
            QMutexLocker locker(&d->delayedEventsMutex);
            Q_ASSERT(!d->delayedEvents.contains(tid));
            return true;
        }
        d->delayedEventsMutex.lock();
        QEvent *ee = d->delayedEvents.take(tid);
        if (ee != 0) {
            killTimer(tid);
            d->delayedEventsMutex.unlock();
            d->postExternalEvent(ee);
            d->processEvents(QStateMachinePrivate::DirectProcessing);
            return true;
        } else {
            d->delayedEventsMutex.unlock();
        }
    }
    return QState::event(e);
}

#ifndef QT_NO_STATEMACHINE_EVENTFILTER
/*!
  \reimp
*/
bool QStateMachine::eventFilter(QObject *watched, QEvent *event)
{
    Q_D(QStateMachine);
    d->handleFilteredEvent(watched, event);
    return false;
}
#endif

/*!
  \internal

  This function is called when the state machine is about to select
  transitions based on the given \a event.

  The default implementation does nothing.
*/
void QStateMachine::beginSelectTransitions(QEvent *event)
{
    Q_UNUSED(event);
}

/*!
  \internal

  This function is called when the state machine has finished selecting
  transitions based on the given \a event.

  The default implementation does nothing.
*/
void QStateMachine::endSelectTransitions(QEvent *event)
{
    Q_UNUSED(event);
}

/*!
  \internal

  This function is called when the state machine is about to do a microstep.

  The default implementation does nothing.
*/
void QStateMachine::beginMicrostep(QEvent *event)
{
    Q_UNUSED(event);
}

/*!
  \internal

  This function is called when the state machine has finished doing a
  microstep.

  The default implementation does nothing.
*/
void QStateMachine::endMicrostep(QEvent *event)
{
    Q_UNUSED(event);
}

/*!
  \reimp
    This function will call start() to start the state machine.
*/
void QStateMachine::onEntry(QEvent *event)
{
    start();
    QState::onEntry(event);
}

/*!
  \reimp
    This function will call stop() to stop the state machine and 
    subsequently emit the stopped() signal.
*/
void QStateMachine::onExit(QEvent *event)
{
    stop();
    QState::onExit(event);
}

#ifndef QT_NO_ANIMATION

/*!
  Returns whether animations are enabled for this state machine.
*/
bool QStateMachine::isAnimated() const
{
    Q_D(const QStateMachine);
    return d->animated;
}

/*!
  Sets whether animations are \a enabled for this state machine.
*/
void QStateMachine::setAnimated(bool enabled)
{
    Q_D(QStateMachine);
    d->animated = enabled;
}

/*!
    Adds a default \a animation to be considered for any transition.
*/    
void QStateMachine::addDefaultAnimation(QAbstractAnimation *animation)
{
    Q_D(QStateMachine);
    d->defaultAnimations.append(animation);
}

/*!
    Returns the list of default animations that will be considered for any transition.
*/
QList<QAbstractAnimation*> QStateMachine::defaultAnimations() const
{    
    Q_D(const QStateMachine);
    return d->defaultAnimations;
}

/*!
    Removes \a animation from the list of default animations. 
*/
void QStateMachine::removeDefaultAnimation(QAbstractAnimation *animation)
{
    Q_D(QStateMachine);
    d->defaultAnimations.removeAll(animation);
}

#endif // QT_NO_ANIMATION


static const uint qt_meta_data_QSignalEventGenerator[] = {

 // content:
       2,       // revision
       0,       // classname
       0,    0, // classinfo
       1,   12, // methods
       0,    0, // properties
       0,    0, // enums/sets
       0,    0, // constructors

 // slots: signature, parameters, type, tag, flags
      23,   22,   22,   22, 0x0a,

       0        // eod
};

static const char qt_meta_stringdata_QSignalEventGenerator[] = {
    "QSignalEventGenerator\0\0execute()\0"
};

const QMetaObject QSignalEventGenerator::staticMetaObject = {
    { &QObject::staticMetaObject, qt_meta_stringdata_QSignalEventGenerator,
      qt_meta_data_QSignalEventGenerator, 0 }
};

const QMetaObject *QSignalEventGenerator::metaObject() const
{
    return &staticMetaObject;
}

void *QSignalEventGenerator::qt_metacast(const char *_clname)
{
    if (!_clname) return 0;
    if (!strcmp(_clname, qt_meta_stringdata_QSignalEventGenerator))
        return static_cast<void*>(const_cast< QSignalEventGenerator*>(this));
    return QObject::qt_metacast(_clname);
}

int QSignalEventGenerator::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
{
    _id = QObject::qt_metacall(_c, _id, _a);
    if (_id < 0)
        return _id;
    if (_c == QMetaObject::InvokeMetaMethod) {
        switch (_id) {
        case 0: {
// ### in Qt 4.6 we can use QObject::senderSignalIndex()
            QObjectPrivate *d = static_cast<QObjectPrivate *>(d_ptr.data());
            int signalIndex = -1;
            QObject *sender = this->sender();
            if (sender && d->currentSender)
                signalIndex = d->currentSender->signal;

            Q_ASSERT(signalIndex != -1);
            QStateMachine *machine = qobject_cast<QStateMachine*>(parent());
            QStateMachinePrivate::get(machine)->handleTransitionSignal(sender, signalIndex, _a);
            break;
        }
        default: ;
        }
        _id -= 1;
    }
    return _id;
}

QSignalEventGenerator::QSignalEventGenerator(QStateMachine *parent)
    : QObject(parent)
{
}

/*!
  \class QStateMachine::SignalEvent

  \brief The SignalEvent class represents a Qt signal event.

  \since 4.6
  \ingroup statemachine

  A signal event is generated by a QStateMachine in response to a Qt
  signal. The QSignalTransition class provides a transition associated with a
  signal event. QStateMachine::SignalEvent is part of \l{The State Machine Framework}.

  The sender() function returns the object that generated the signal. The
  signalIndex() function returns the index of the signal. The arguments()
  function returns the arguments of the signal.

  \sa QSignalTransition
*/

/*!
  \internal

  Constructs a new SignalEvent object with the given \a sender, \a
  signalIndex and \a arguments.
*/
QStateMachine::SignalEvent::SignalEvent(QObject *sender, int signalIndex,
                                        const QList<QVariant> &arguments)
    : QEvent(QEvent::StateMachineSignal), m_sender(sender),
      m_signalIndex(signalIndex), m_arguments(arguments)
{
}

/*!
  Destroys this SignalEvent.
*/
QStateMachine::SignalEvent::~SignalEvent()
{
}

/*!
  \fn QStateMachine::SignalEvent::sender() const

  Returns the object that emitted the signal.

  \sa QObject::sender()
*/

/*!
  \fn QStateMachine::SignalEvent::signalIndex() const

  Returns the index of the signal.

  \sa QMetaObject::indexOfSignal(), QMetaObject::method()
*/

/*!
  \fn QStateMachine::SignalEvent::arguments() const

  Returns the arguments of the signal.
*/


/*!
  \class QStateMachine::WrappedEvent

  \brief The WrappedEvent class inherits QEvent and holds a clone of an event associated with a QObject.

  \since 4.6
  \ingroup statemachine

  A wrapped event is generated by a QStateMachine in response to a Qt
  event. The QEventTransition class provides a transition associated with a
  such an event. QStateMachine::WrappedEvent is part of \l{The State Machine
  Framework}.

  The object() function returns the object that generated the event. The
  event() function returns a clone of the original event.

  \sa QEventTransition
*/

/*!
  \internal

  Constructs a new WrappedEvent object with the given \a object
  and \a event.

  The WrappedEvent object takes ownership of \a event.
*/
QStateMachine::WrappedEvent::WrappedEvent(QObject *object, QEvent *event)
    : QEvent(QEvent::StateMachineWrapped), m_object(object), m_event(event)
{
}

/*!
  Destroys this WrappedEvent.
*/
QStateMachine::WrappedEvent::~WrappedEvent()
{
    delete m_event;
}

/*!
  \fn QStateMachine::WrappedEvent::object() const

  Returns the object that the event is associated with.
*/

/*!
  \fn QStateMachine::WrappedEvent::event() const

  Returns a clone of the original event.
*/

QT_END_NAMESPACE

#include "moc_qstatemachine.cpp"

#endif //QT_NO_STATEMACHINE