summaryrefslogtreecommitdiffstats
path: root/src/H5Spoint.c
blob: 3cc0a841c3cd332873fb1433dc373fd1c01104c4 (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
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the COPYING file, which can be found at the root of the source code       *
 * distribution tree, or in https://www.hdfgroup.org/licenses.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer:  Quincey Koziol
 *              Tuesday, June 16, 1998
 *
 * Purpose:     Point selection dataspace I/O functions.
 */

#define H5S_PACKAGE /*suppress error about including H5Spkg      */

#include "H5private.h"   /* Generic Functions              */
#include "H5Eprivate.h"  /* Error handling          */
#include "H5FLprivate.h" /* Free Lists      */
#include "H5Iprivate.h"  /* ID Functions          */
#include "H5MMprivate.h" /* Memory Management functions          */
#include "H5Spkg.h"      /* Dataspace functions              */
#include "H5VMprivate.h" /* Vector functions */

/* Static function prototypes */

/* Selection callbacks */
static herr_t H5S_point_copy(H5S_t *dst, const H5S_t *src, hbool_t share_selection);
static herr_t H5S_point_get_seq_list(const H5S_t *space, unsigned flags, H5S_sel_iter_t *iter, size_t maxseq,
                                     size_t maxbytes, size_t *nseq, size_t *nbytes, hsize_t *off,
                                     size_t *len);
static herr_t H5S_point_release(H5S_t *space);
static htri_t H5S_point_is_valid(const H5S_t *space);
static hssize_t H5S_point_serial_size(const H5S_t *space);
static herr_t   H5S_point_serialize(const H5S_t *space, uint8_t *buf);
static herr_t   H5S_point_deserialize(H5S_t *space, const uint8_t *buf);
static herr_t   H5S_point_bounds(const H5S_t *space, hsize_t *start, hsize_t *end);
static herr_t   H5S_point_offset(const H5S_t *space, hsize_t *off);
static htri_t   H5S_point_is_contiguous(const H5S_t *space);
static htri_t   H5S_point_is_single(const H5S_t *space);
static htri_t   H5S_point_is_regular(const H5S_t *space);
static herr_t   H5S_point_adjust_u(H5S_t *space, const hsize_t *offset);
static herr_t   H5S_point_project_scalar(const H5S_t *space, hsize_t *offset);
static herr_t   H5S_point_project_simple(const H5S_t *space, H5S_t *new_space, hsize_t *offset);
static herr_t   H5S_point_iter_init(H5S_sel_iter_t *iter, const H5S_t *space);

/* Selection iteration callbacks */
static herr_t  H5S_point_iter_coords(const H5S_sel_iter_t *iter, hsize_t *coords);
static herr_t  H5S_point_iter_block(const H5S_sel_iter_t *iter, hsize_t *start, hsize_t *end);
static hsize_t H5S_point_iter_nelmts(const H5S_sel_iter_t *iter);
static htri_t  H5S_point_iter_has_next_block(const H5S_sel_iter_t *iter);
static herr_t  H5S_point_iter_next(H5S_sel_iter_t *sel_iter, size_t nelem);
static herr_t  H5S_point_iter_next_block(H5S_sel_iter_t *sel_iter);
static herr_t  H5S_point_iter_release(H5S_sel_iter_t *sel_iter);

/* Selection properties for point selections */
const H5S_select_class_t H5S_sel_point[1] = {{
    H5S_SEL_POINTS,

    /* Methods on selection */
    H5S_point_copy,
    H5S_point_get_seq_list,
    H5S_point_release,
    H5S_point_is_valid,
    H5S_point_serial_size,
    H5S_point_serialize,
    H5S_point_deserialize,
    H5S_point_bounds,
    H5S_point_offset,
    H5S_point_is_contiguous,
    H5S_point_is_single,
    H5S_point_is_regular,
    H5S_point_adjust_u,
    H5S_point_project_scalar,
    H5S_point_project_simple,
    H5S_point_iter_init,
}};

/* Iteration properties for point selections */
static const H5S_sel_iter_class_t H5S_sel_iter_point[1] = {{
    H5S_SEL_POINTS,

    /* Methods on selection iterator */
    H5S_point_iter_coords,
    H5S_point_iter_block,
    H5S_point_iter_nelmts,
    H5S_point_iter_has_next_block,
    H5S_point_iter_next,
    H5S_point_iter_next_block,
    H5S_point_iter_release,
}};

/* Declare a free list to manage the H5S_pnt_node_t struct */
H5FL_DEFINE_STATIC(H5S_pnt_node_t);

/* Declare a free list to manage the H5S_pnt_list_t struct */
H5FL_DEFINE_STATIC(H5S_pnt_list_t);

/*-------------------------------------------------------------------------
 * Function:    H5S_point_iter_init
 *
 * Purpose:     Initializes iteration information for point selection.
 *
 * Return:      Non-negative on success, negative on failure.
 *
 * Programmer:  Quincey Koziol
 *              Tuesday, June 16, 1998
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5S_point_iter_init(H5S_sel_iter_t *iter, const H5S_t *space)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(space && H5S_SEL_POINTS == H5S_GET_SELECT_TYPE(space));
    HDassert(iter);

    /* Initialize the number of points to iterate over */
    iter->elmt_left = space->select.num_elem;

    /* Start at the head of the list of points */
    iter->u.pnt.curr = space->select.sel_info.pnt_lst->head;

    /* Initialize type of selection iterator */
    iter->type = H5S_sel_iter_point;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_init() */

/*-------------------------------------------------------------------------
 * Function:    H5S_point_iter_coords
 *
 * Purpose:     Retrieve the current coordinates of iterator for current
 *              selection
 *
 * Return:      Non-negative on success, negative on failure
 *
 * Programmer:  Quincey Koziol
 *              Tuesday, April 22, 2003
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5S_point_iter_coords(const H5S_sel_iter_t *iter, hsize_t *coords)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);
    HDassert(coords);

    /* Copy the offset of the current point */
    HDmemcpy(coords, iter->u.pnt.curr->pnt, sizeof(hsize_t) * iter->rank);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_coords() */

/*-------------------------------------------------------------------------
 * Function:    H5S_point_iter_block
 *
 * Purpose:     Retrieve the current block of iterator for current
 *              selection
 *
 * Return:      Non-negative on success, negative on failure
 *
 * Programmer:  Quincey Koziol
 *              Monday, June 2, 2003
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5S_point_iter_block(const H5S_sel_iter_t *iter, hsize_t *start, hsize_t *end)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);
    HDassert(start);
    HDassert(end);

    /* Copy the current point as a block */
    HDmemcpy(start, iter->u.pnt.curr->pnt, sizeof(hsize_t) * iter->rank);
    HDmemcpy(end, iter->u.pnt.curr->pnt, sizeof(hsize_t) * iter->rank);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_block() */

/*-------------------------------------------------------------------------
 * Function:    H5S_point_iter_nelmts
 *
 * Purpose:     Return number of elements left to process in iterator
 *
 * Return:      Non-negative number of elements on success, zero on failure
 *
 * Programmer:  Quincey Koziol
 *              Tuesday, June 16, 1998
 *
 *-------------------------------------------------------------------------
 */
static hsize_t
H5S_point_iter_nelmts(const H5S_sel_iter_t *iter)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);

    FUNC_LEAVE_NOAPI(iter->elmt_left)
} /* H5S_point_iter_nelmts() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_iter_has_next_block
 PURPOSE
    Check if there is another block left in the current iterator
 USAGE
    htri_t H5S_point_iter_has_next_block(iter)
        const H5S_sel_iter_t *iter;       IN: Pointer to selection iterator
 RETURNS
    Non-negative (TRUE/FALSE) on success/Negative on failure
 DESCRIPTION
    Check if there is another block available in the selection iterator.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static htri_t
H5S_point_iter_has_next_block(const H5S_sel_iter_t *iter)
{
    htri_t ret_value = TRUE; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);

    /* Check if there is another point in the list */
    if (iter->u.pnt.curr->next == NULL)
        HGOTO_DONE(FALSE);

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_iter_has_next_block() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_iter_next
 PURPOSE
    Increment selection iterator
 USAGE
    herr_t H5S_point_iter_next(iter, nelem)
        H5S_sel_iter_t *iter;       IN: Pointer to selection iterator
        size_t nelem;               IN: Number of elements to advance by
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Advance selection iterator to the NELEM'th next element in the selection.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_iter_next(H5S_sel_iter_t *iter, size_t nelem)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);
    HDassert(nelem > 0);

    /* Increment the iterator */
    while (nelem > 0) {
        iter->u.pnt.curr = iter->u.pnt.curr->next;
        nelem--;
    } /* end while */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_next() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_iter_next_block
 PURPOSE
    Increment selection iterator to next block
 USAGE
    herr_t H5S_point_iter_next_block(iter)
        H5S_sel_iter_t *iter;       IN: Pointer to selection iterator
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Advance selection iterator to the next block in the selection.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_iter_next_block(H5S_sel_iter_t *iter)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);

    /* Increment the iterator */
    iter->u.pnt.curr = iter->u.pnt.curr->next;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_next_block() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_iter_release
 PURPOSE
    Release point selection iterator information for a dataspace
 USAGE
    herr_t H5S_point_iter_release(iter)
        H5S_sel_iter_t *iter;       IN: Pointer to selection iterator
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Releases all information for a dataspace point selection iterator
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_iter_release(H5S_sel_iter_t H5_ATTR_UNUSED *iter)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(iter);

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_iter_release() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_add
 PURPOSE
    Add a series of elements to a point selection
 USAGE
    herr_t H5S_point_add(space, num_elem, coord)
        H5S_t *space;           IN: Dataspace of selection to modify
        size_t num_elem;        IN: Number of elements in COORD array.
        const hsize_t *coord[];    IN: The location of each element selected
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    This function adds elements to the current point selection for a dataspace
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_add(H5S_t *space, H5S_seloper_t op, size_t num_elem, const hsize_t *coord)
{
    H5S_pnt_node_t *top = NULL, *curr = NULL, *new_node = NULL; /* Point selection nodes */
    unsigned        u;                                          /* Counter */
    herr_t          ret_value = SUCCEED;                        /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(space);
    HDassert(num_elem > 0);
    HDassert(coord);
    HDassert(op == H5S_SELECT_SET || op == H5S_SELECT_APPEND || op == H5S_SELECT_PREPEND);

    for (u = 0; u < num_elem; u++) {
        /* Allocate space for the new node */
        if (NULL == (new_node = H5FL_MALLOC(H5S_pnt_node_t)))
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point node")

        /* Initialize fields in node */
        new_node->next = NULL;
        if (NULL == (new_node->pnt = (hsize_t *)H5MM_malloc(space->extent.rank * sizeof(hsize_t))))
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate coordinate information")

        /* Copy over the coordinates */
        HDmemcpy(new_node->pnt, coord + (u * space->extent.rank), (space->extent.rank * sizeof(hsize_t)));

        /* Link into list */
        if (top == NULL)
            top = new_node;
        else
            curr->next = new_node;
        curr = new_node;
    } /* end for */
    new_node = NULL;

    /* Insert the list of points selected in the proper place */
    if (op == H5S_SELECT_SET || op == H5S_SELECT_PREPEND) {
        /* Append current list, if there is one */
        if (space->select.sel_info.pnt_lst->head != NULL)
            curr->next = space->select.sel_info.pnt_lst->head;

        /* Put new list in point selection */
        space->select.sel_info.pnt_lst->head = top;
    }                             /* end if */
    else {                        /* op==H5S_SELECT_APPEND */
        H5S_pnt_node_t *tmp_node; /* Temporary point selection node */

        tmp_node = space->select.sel_info.pnt_lst->head;
        if (tmp_node != NULL) {
            while (tmp_node->next != NULL)
                tmp_node = tmp_node->next;

            /* Append new list to point selection */
            tmp_node->next = top;
        } /* end if */
        else
            space->select.sel_info.pnt_lst->head = top;
    } /* end else */

    /* Set the number of elements in the new selection */
    if (op == H5S_SELECT_SET)
        space->select.num_elem = num_elem;
    else
        space->select.num_elem += num_elem;

done:
    if (ret_value < 0) {
        /* Release possibly partially initialized new node */
        if (new_node)
            new_node = H5FL_FREE(H5S_pnt_node_t, new_node);

        /* Release possible linked list of nodes */
        while (top) {
            curr = top->next;
            H5MM_xfree(top->pnt);
            top = H5FL_FREE(H5S_pnt_node_t, top);
            top = curr;
        } /* end while */
    }     /* end if */

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_add() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_release
 PURPOSE
    Release point selection information for a dataspace
 USAGE
    herr_t H5S_point_release(space)
        H5S_t *space;       IN: Pointer to dataspace
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Releases all point selection information for a dataspace
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_release(H5S_t *space)
{
    H5S_pnt_node_t *curr, *next; /* Point selection nodes */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(space);

    /* Delete all the nodes from the list */
    curr = space->select.sel_info.pnt_lst->head;
    while (curr != NULL) {
        next = curr->next;
        H5MM_xfree(curr->pnt);
        curr = H5FL_FREE(H5S_pnt_node_t, curr);
        curr = next;
    } /* end while */

    /* Free & reset the point list header */
    space->select.sel_info.pnt_lst = H5FL_FREE(H5S_pnt_list_t, space->select.sel_info.pnt_lst);

    /* Reset the number of elements in the selection */
    space->select.num_elem = 0;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_release() */

/*--------------------------------------------------------------------------
 NAME
    H5S_select_elements
 PURPOSE
    Specify a series of elements in the dataspace to select
 USAGE
    herr_t H5S_select_elements(dsid, op, num_elem, coord)
        hid_t dsid;             IN: Dataspace ID of selection to modify
        H5S_seloper_t op;       IN: Operation to perform on current selection
        size_t num_elem;        IN: Number of elements in COORD array.
        const hsize_t *coord;   IN: The location of each element selected
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    This function selects array elements to be included in the selection for
    the dataspace.  The COORD array is a 2-D array of size <dataspace rank>
    by NUM_ELEM (ie. a list of coordinates in the dataspace).  The order of
    the element coordinates in the COORD array specifies the order that the
    array elements are iterated through when I/O is performed.  Duplicate
    coordinates are not checked for.  The selection operator, OP, determines
    how the new selection is to be combined with the existing selection for
    the dataspace.  Currently, only H5S_SELECT_SET is supported, which replaces
    the existing selection with the one defined in this call.  When operators
    other than H5S_SELECT_SET are used to combine a new selection with an
    existing selection, the selection ordering is reset to 'C' array ordering.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
herr_t
H5S_select_elements(H5S_t *space, H5S_seloper_t op, size_t num_elem, const hsize_t *coord)
{
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    HDassert(space);
    HDassert(num_elem);
    HDassert(coord);
    HDassert(op == H5S_SELECT_SET || op == H5S_SELECT_APPEND || op == H5S_SELECT_PREPEND);

    /* If we are setting a new selection, remove current selection first */
    if (op == H5S_SELECT_SET || H5S_GET_SELECT_TYPE(space) != H5S_SEL_POINTS)
        if (H5S_SELECT_RELEASE(space) < 0)
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTDELETE, FAIL, "can't release point selection")

    /* Allocate space for the point selection information if necessary */
    if (H5S_GET_SELECT_TYPE(space) != H5S_SEL_POINTS || space->select.sel_info.pnt_lst == NULL)
        if (NULL == (space->select.sel_info.pnt_lst = H5FL_CALLOC(H5S_pnt_list_t)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate element information")

    /* Add points to selection */
    if (H5S_point_add(space, op, num_elem, coord) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINSERT, FAIL, "can't insert elements")

    /* Set selection type */
    space->select.type = H5S_sel_point;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_select_elements() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_copy
 PURPOSE
    Copy a selection from one dataspace to another
 USAGE
    herr_t H5S_point_copy(dst, src)
        H5S_t *dst;  OUT: Pointer to the destination dataspace
        H5S_t *src;  IN: Pointer to the source dataspace
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Copies all the point selection information from the source
    dataspace to the destination dataspace.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_copy(H5S_t *dst, const H5S_t *src, hbool_t H5_ATTR_UNUSED share_selection)
{
    H5S_pnt_node_t *curr, *new_node, *new_tail; /* Point information nodes */
    herr_t          ret_value = SUCCEED;        /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(src);
    HDassert(dst);

    /* Allocate room for the head of the point list */
    if (NULL == (dst->select.sel_info.pnt_lst = H5FL_MALLOC(H5S_pnt_list_t)))
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point list node")

    curr     = src->select.sel_info.pnt_lst->head;
    new_tail = NULL;
    while (curr) {
        /* Create new point */
        if (NULL == (new_node = H5FL_MALLOC(H5S_pnt_node_t)))
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point node")
        new_node->next = NULL;
        if (NULL == (new_node->pnt = (hsize_t *)H5MM_malloc(src->extent.rank * sizeof(hsize_t)))) {
            new_node = H5FL_FREE(H5S_pnt_node_t, new_node);
            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate coordinate information")
        } /* end if */

        /* Copy over the point's coordinates */
        HDmemcpy(new_node->pnt, curr->pnt, (src->extent.rank * sizeof(hsize_t)));

        /* Keep the order the same when copying */
        if (NULL == new_tail)
            new_tail = dst->select.sel_info.pnt_lst->head = new_node;
        else {
            new_tail->next = new_node;
            new_tail       = new_node;
        } /* end else */

        curr = curr->next;
    } /* end while */

    /* Clear cached iteration point */
    dst->select.sel_info.pnt_lst->last_idx     = 0;
    dst->select.sel_info.pnt_lst->last_idx_pnt = NULL;

done:
    if (ret_value < 0 && dst->select.sel_info.pnt_lst) {
        /* Traverse the (incomplete?) dst list, freeing all memory */
        curr = dst->select.sel_info.pnt_lst->head;
        while (curr) {
            H5S_pnt_node_t *tmp_node = curr;

            curr->pnt = (hsize_t *)H5MM_xfree(curr->pnt);
            curr      = curr->next;
            tmp_node  = H5FL_FREE(H5S_pnt_node_t, tmp_node);
        } /* end while */

        dst->select.sel_info.pnt_lst = H5FL_FREE(H5S_pnt_list_t, dst->select.sel_info.pnt_lst);
    } /* end if */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5S_point_copy() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_is_valid
 PURPOSE
    Check whether the selection fits within the extent, with the current
    offset defined.
 USAGE
    htri_t H5S_point_is_valid(space);
        H5S_t *space;             IN: Dataspace pointer to query
 RETURNS
    TRUE if the selection fits within the extent, FALSE if it does not and
        Negative on an error.
 DESCRIPTION
    Determines if the current selection at the current offset fits within the
    extent for the dataspace.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static htri_t
H5S_point_is_valid(const H5S_t *space)
{
    H5S_pnt_node_t *curr;             /* Point information nodes */
    unsigned        u;                /* Counter */
    htri_t          ret_value = TRUE; /* return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);

    /* Check each point to determine whether selection+offset is within extent */
    curr = space->select.sel_info.pnt_lst->head;
    while (curr != NULL) {
        /* Check each dimension */
        for (u = 0; u < space->extent.rank; u++) {
            /* Check if an offset has been defined */
            /* Bounds check the selected point + offset against the extent */
            if (((curr->pnt[u] + (hsize_t)space->select.offset[u]) > space->extent.size[u]) ||
                (((hssize_t)curr->pnt[u] + space->select.offset[u]) < 0))
                HGOTO_DONE(FALSE)
        } /* end for */

        curr = curr->next;
    } /* end while */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5S_point_is_valid() */

/*--------------------------------------------------------------------------
 NAME
    H5Sget_select_elem_npoints
 PURPOSE
    Get the number of points in current element selection
 USAGE
    hssize_t H5Sget_select_elem_npoints(dsid)
        hid_t dsid;             IN: Dataspace ID of selection to query
 RETURNS
    The number of element points in selection on success, negative on failure
 DESCRIPTION
    Returns the number of element points in current selection for dataspace.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
hssize_t
H5Sget_select_elem_npoints(hid_t spaceid)
{
    H5S_t *  space;     /* Dataspace to modify selection of */
    hssize_t ret_value; /* return value */

    FUNC_ENTER_API(FAIL)
    H5TRACE1("Hs", "i", spaceid);

    /* Check args */
    if (NULL == (space = (H5S_t *)H5I_object_verify(spaceid, H5I_DATASPACE)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace")
    if (H5S_GET_SELECT_TYPE(space) != H5S_SEL_POINTS)
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an element selection")

    ret_value = (hssize_t)H5S_GET_SELECT_NPOINTS(space);

done:
    FUNC_LEAVE_API(ret_value)
} /* H5Sget_select_elem_npoints() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_serial_size
 PURPOSE
    Determine the number of bytes needed to store the serialized point selection
    information.
 USAGE
    hssize_t H5S_point_serial_size(space)
        H5S_t *space;             IN: Dataspace pointer to query
 RETURNS
    The number of bytes required on success, negative on an error.
 DESCRIPTION
    Determines the number of bytes required to serialize the current point
    selection information for storage on disk.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static hssize_t
H5S_point_serial_size(const H5S_t *space)
{
    H5S_pnt_node_t *curr;      /* Point information nodes */
    hssize_t        ret_value; /* return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);

    /* Basic number of bytes required to serialize point selection:
     *  <type (4 bytes)> + <version (4 bytes)> + <padding (4 bytes)> +
     *      <length (4 bytes)> + <rank (4 bytes)> + <# of points (4 bytes)> = 24 bytes
     */
    ret_value = 24;

    /* Count points in selection */
    curr = space->select.sel_info.pnt_lst->head;
    while (curr != NULL) {
        /* Add 4 bytes times the rank for each element selected */
        ret_value += 4 * space->extent.rank;
        curr = curr->next;
    } /* end while */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5S_point_serial_size() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_serialize
 PURPOSE
    Serialize the current selection into a user-provided buffer.
 USAGE
    herr_t H5S_point_serialize(space, buf)
        H5S_t *space;           IN: Dataspace pointer of selection to serialize
        uint8 *buf;             OUT: Buffer to put serialized selection into
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Serializes the current element selection into a buffer.  (Primarily for
    storing on disk).
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_serialize(const H5S_t *space, uint8_t *buf)
{
    H5S_pnt_node_t *curr;                       /* Point information nodes */
    uint8_t *       lenp;                       /* pointer to length location for later storage */
    uint32_t        len = 0;                    /* number of bytes used */
    unsigned        u;                          /* local counting variable */
    hsize_t         bounds_start[H5S_MAX_RANK]; /* Selection bounding box */
    hsize_t         bounds_end[H5S_MAX_RANK];   /* Selection bounding box */
    herr_t          ret_value = SUCCEED;        /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(space);

    /* Get bounding box for the selection */
    HDmemset(bounds_end, 0, sizeof(bounds_end));
    if (H5S_point_bounds(space, bounds_start, bounds_end) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "can't get selection bounds")

    /* Determine whether the number of points or the high bounds in the selection exceed (2^32 - 1) */
    if (space->select.num_elem > H5S_UINT32_MAX)
        HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "invalid number of points in selection")
    else {
        for (u = 0; u < space->extent.rank; u++)
            if (bounds_end[u] > H5S_UINT32_MAX)
                HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "invalid points selection")
    }

    /* Store the preamble information */
    UINT32ENCODE(buf, (uint32_t)H5S_GET_SELECT_TYPE(space)); /* Store the type of selection */
    UINT32ENCODE(buf, (uint32_t)H5S_POINT_VERSION_1);        /* Store the version number */
    UINT32ENCODE(buf, (uint32_t)0);                          /* Store the un-used padding */
    lenp = buf; /* keep the pointer to the length location for later */
    buf += 4;   /* skip over space for length */

    /* Encode number of dimensions */
    UINT32ENCODE(buf, (uint32_t)space->extent.rank);
    len += 4;

    /* Encode number of elements */
    UINT32ENCODE(buf, (uint32_t)space->select.num_elem);
    len += 4;

    /* Encode each point in selection */
    curr = space->select.sel_info.pnt_lst->head;
    while (curr != NULL) {
        /* Add 4 bytes times the rank for each element selected */
        len += 4 * space->extent.rank;

        /* Encode each point */
        for (u = 0; u < space->extent.rank; u++)
            UINT32ENCODE(buf, (uint32_t)curr->pnt[u]);

        curr = curr->next;
    } /* end while */

    /* Encode length */
    UINT32ENCODE(lenp, (uint32_t)len); /* Store the length of the extra information */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_serialize() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_deserialize
 PURPOSE
    Deserialize the current selection from a user-provided buffer.
 USAGE
    herr_t H5S_point_deserialize(space, buf)
        H5S_t *space;           IN/OUT: Dataspace pointer to place selection into
        uint8 *buf;             IN: Buffer to retrieve serialized selection from
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    Deserializes the current selection into a buffer.  (Primarily for retrieving
    from disk).
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_deserialize(H5S_t *space, const uint8_t *buf)
{
    H5S_seloper_t op = H5S_SELECT_SET;      /* Selection operation */
    uint32_t      rank;                     /* Rank of points */
    size_t        num_elem = 0;             /* Number of elements in selection */
    hsize_t *     coord    = NULL, *tcoord; /* Pointer to array of elements */
    unsigned      i, j;                     /* local counting variables */
    uint32_t      version;                  /* Decoded version */
    uint8_t *     p;                        /* Temporary pointer to buf */
    herr_t        ret_value = SUCCEED;      /* return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    HDassert(space);
    HDassert(buf);

    p = buf + 4;
    UINT32DECODE(p, version);

    if (version < H5S_POINT_VERSION_1 || version > H5S_POINT_VERSION_LATEST)
        HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "bad version number for point selection")

    /* Deserialize points to select */
    buf += 16;               /* Skip over selection header */
    UINT32DECODE(buf, rank); /* decode the rank of the point selection */
    if (rank != space->extent.rank)
        HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "rank of pointer does not match dataspace")
    UINT32DECODE(buf, num_elem); /* decode the number of points */

    /* Allocate space for the coordinates */
    if (NULL == (coord = (hsize_t *)H5MM_malloc(num_elem * rank * sizeof(hsize_t))))
        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "can't allocate coordinate information")

    /* Retrieve the coordinates from the buffer */
    for (tcoord = coord, i = 0; i < num_elem; i++)
        for (j = 0; j < (unsigned)rank; j++, tcoord++)
            UINT32DECODE(buf, *tcoord);

    /* Select points */
    if (H5S_select_elements(space, op, num_elem, (const hsize_t *)coord) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTDELETE, FAIL, "can't change selection")

done:
    /* Free the coordinate array if necessary */
    if (coord != NULL)
        H5MM_xfree(coord);

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_deserialize() */

/*--------------------------------------------------------------------------
 NAME
    H5S_get_select_elem_pointlist
 PURPOSE
    Get the list of element points currently selected
 USAGE
    herr_t H5S_get_select_elem_pointlist(space, hsize_t *buf)
        H5S_t *space;           IN: Dataspace pointer of selection to query
        hsize_t startpoint;     IN: Element point to start with
        hsize_t numpoints;      IN: Number of element points to get
        hsize_t *buf;           OUT: List of element points selected
 RETURNS
    Non-negative on success, negative on failure
 DESCRIPTION
        Puts a list of the element points into the user's buffer.  The points
    start with the 'startpoint'th block in the list of points and put
    'numpoints' number of points into the user's buffer (or until the end of
    the list of points, whichever happen first)
        The point coordinates have the same dimensionality (rank) as the
    dataspace they are located within.  The list of points is formatted as
    follows: <coordinate> followed by the next coordinate, etc. until all the
    point information in the selection have been put into the user's buffer.
        The points are returned in the order they will be interated through
    when a selection is read/written from/to disk.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_get_select_elem_pointlist(H5S_t *space, hsize_t startpoint, hsize_t numpoints, hsize_t *buf)
{
    const hsize_t   endpoint = startpoint + numpoints; /* Index of last point in iteration */
    H5S_pnt_node_t *node;                              /* Point node */
    unsigned        rank;                              /* Dataspace rank */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);
    HDassert(buf);

    /* Get the dataspace extent rank */
    rank = space->extent.rank;

    /* Check for cached point at the correct index */
    if (space->select.sel_info.pnt_lst->last_idx_pnt &&
        startpoint == space->select.sel_info.pnt_lst->last_idx)
        node = space->select.sel_info.pnt_lst->last_idx_pnt;
    else {
        /* Get the head of the point list */
        node = space->select.sel_info.pnt_lst->head;

        /* Iterate to the first point to return */
        while (node != NULL && startpoint > 0) {
            startpoint--;
            node = node->next;
        } /* end while */
    }     /* end else */

    /* Iterate through the node, copying each point's information */
    while (node != NULL && numpoints > 0) {
        HDmemcpy(buf, node->pnt, sizeof(hsize_t) * rank);
        buf += rank;
        numpoints--;
        node = node->next;
    } /* end while */

    /* Cached next point in iteration */
    space->select.sel_info.pnt_lst->last_idx     = endpoint;
    space->select.sel_info.pnt_lst->last_idx_pnt = node;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_get_select_elem_pointlist() */

/*--------------------------------------------------------------------------
 NAME
    H5Sget_select_elem_pointlist
 PURPOSE
    Get the list of element points currently selected
 USAGE
    herr_t H5Sget_select_elem_pointlist(dsid, hsize_t *buf)
        hid_t dsid;             IN: Dataspace ID of selection to query
        hsize_t startpoint;     IN: Element point to start with
        hsize_t numpoints;      IN: Number of element points to get
        hsize_t buf[];          OUT: List of element points selected
 RETURNS
    Non-negative on success, negative on failure
 DESCRIPTION
        Puts a list of the element points into the user's buffer.  The points
    start with the 'startpoint'th block in the list of points and put
    'numpoints' number of points into the user's buffer (or until the end of
    the list of points, whichever happen first)
        The point coordinates have the same dimensionality (rank) as the
    dataspace they are located within.  The list of points is formatted as
    follows: <coordinate> followed by the next coordinate, etc. until all the
    point information in the selection have been put into the user's buffer.
        The points are returned in the order they will be interated through
    when a selection is read/written from/to disk.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
herr_t
H5Sget_select_elem_pointlist(hid_t spaceid, hsize_t startpoint, hsize_t numpoints, hsize_t buf[/*numpoints*/])
{
    H5S_t *space;     /* Dataspace to modify selection of */
    herr_t ret_value; /* return value */

    FUNC_ENTER_API(FAIL)
    H5TRACE4("e", "ihh*[a2]h", spaceid, startpoint, numpoints, buf);

    /* Check args */
    if (NULL == buf)
        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid pointer")
    if (NULL == (space = (H5S_t *)H5I_object_verify(spaceid, H5I_DATASPACE)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace")
    if (H5S_GET_SELECT_TYPE(space) != H5S_SEL_POINTS)
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a point selection")

    ret_value = H5S_get_select_elem_pointlist(space, startpoint, numpoints, buf);

done:
    FUNC_LEAVE_API(ret_value)
} /* H5Sget_select_elem_pointlist() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_bounds
 PURPOSE
    Gets the bounding box containing the selection.
 USAGE
    herr_t H5S_point_bounds(space, start, end)
        H5S_t *space;           IN: Dataspace pointer of selection to query
        hsize_t *start;         OUT: Starting coordinate of bounding box
        hsize_t *end;           OUT: Opposite coordinate of bounding box
 RETURNS
    Non-negative on success, negative on failure
 DESCRIPTION
    Retrieves the bounding box containing the current selection and places
    it into the user's buffers.  The start and end buffers must be large
    enough to hold the dataspace rank number of coordinates.  The bounding box
    exactly contains the selection, ie. if a 2-D element selection is currently
    defined with the following points: (4,5), (6,8) (10,7), the bounding box
    with be (4, 5), (10, 8).
        The bounding box calculations _does_ include the current offset of the
    selection within the dataspace extent.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_bounds(const H5S_t *space, hsize_t *start, hsize_t *end)
{
    H5S_pnt_node_t *node;                /* Point node */
    unsigned        rank;                /* Dataspace rank */
    unsigned        u;                   /* index variable */
    herr_t          ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(space);
    HDassert(start);
    HDassert(end);

    /* Get the dataspace extent rank */
    rank = space->extent.rank;

    /* Set the start and end arrays up */
    for (u = 0; u < rank; u++) {
        start[u] = HSIZET_MAX;
        end[u]   = 0;
    } /* end for */

    /* Iterate through the node, checking the bounds on each element */
    node = space->select.sel_info.pnt_lst->head;
    while (node != NULL) {
        for (u = 0; u < rank; u++) {
            /* Check for offset moving selection negative */
            if (((hssize_t)node->pnt[u] + space->select.offset[u]) < 0)
                HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "offset moves selection out of bounds")

            if (start[u] > (node->pnt[u] + space->select.offset[u]))
                start[u] = node->pnt[u] + space->select.offset[u];
            if (end[u] < (node->pnt[u] + space->select.offset[u]))
                end[u] = node->pnt[u] + space->select.offset[u];
        } /* end for */
        node = node->next;
    } /* end while */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_bounds() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_offset
 PURPOSE
    Gets the linear offset of the first element for the selection.
 USAGE
    herr_t H5S_point_offset(space, offset)
        const H5S_t *space;     IN: Dataspace pointer of selection to query
        hsize_t *offset;        OUT: Linear offset of first element in selection
 RETURNS
    Non-negative on success, negative on failure
 DESCRIPTION
    Retrieves the linear offset (in "units" of elements) of the first element
    selected within the dataspace.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
    Calling this function on a "none" selection returns fail.
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_offset(const H5S_t *space, hsize_t *offset)
{
    const hsize_t * pnt;                 /* Pointer to a selected point's coordinates */
    const hssize_t *sel_offset;          /* Pointer to the selection's offset */
    const hsize_t * dim_size;            /* Pointer to a dataspace's extent */
    hsize_t         accum;               /* Accumulator for dimension sizes */
    int             i;                   /* index variable */
    herr_t          ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

    HDassert(space);
    HDassert(offset);

    /* Start at linear offset 0 */
    *offset = 0;

    /* Set up pointers to arrays of values */
    pnt        = space->select.sel_info.pnt_lst->head->pnt;
    sel_offset = space->select.offset;
    dim_size   = space->extent.size;

    /* Loop through coordinates, calculating the linear offset */
    accum = 1;
    for (i = (int)space->extent.rank - 1; i >= 0; i--) {
        hssize_t pnt_offset = (hssize_t)pnt[i] + sel_offset[i]; /* Point's offset in this dimension */

        /* Check for offset moving selection out of the dataspace */
        if (pnt_offset < 0 || (hsize_t)pnt_offset >= dim_size[i])
            HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL, "offset moves selection out of bounds")

        /* Add the point's offset in this dimension to the total linear offset */
        *offset += (hsize_t)pnt_offset * accum;

        /* Increase the accumulator */
        accum *= dim_size[i];
    } /* end for */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_offset() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_is_contiguous
 PURPOSE
    Check if a point selection is contiguous within the dataspace extent.
 USAGE
    htri_t H5S_point_is_contiguous(space)
        H5S_t *space;           IN: Dataspace pointer to check
 RETURNS
    TRUE/FALSE/FAIL
 DESCRIPTION
    Checks to see if the current selection in the dataspace is contiguous.
    This is primarily used for reading the entire selection in one swoop.
    This code currently doesn't properly check for contiguousness when there is
    more than one point, as that would take a lot of extra coding that we
    don't need now.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static htri_t
H5S_point_is_contiguous(const H5S_t *space)
{
    htri_t ret_value = FAIL; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);

    /* One point is definitely contiguous */
    if (space->select.num_elem == 1)
        ret_value = TRUE;
    else /* More than one point might be contiguous, but it's complex to check and we don't need it right now
          */
        ret_value = FALSE;

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_is_contiguous() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_is_single
 PURPOSE
    Check if a point selection is single within the dataspace extent.
 USAGE
    htri_t H5S_point_is_single(space)
        H5S_t *space;           IN: Dataspace pointer to check
 RETURNS
    TRUE/FALSE/FAIL
 DESCRIPTION
    Checks to see if the current selection in the dataspace is a single block.
    This is primarily used for reading the entire selection in one swoop.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static htri_t
H5S_point_is_single(const H5S_t *space)
{
    htri_t ret_value = FAIL; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);

    /* One point is definitely 'single' :-) */
    if (space->select.num_elem == 1)
        ret_value = TRUE;
    else
        ret_value = FALSE;

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_is_single() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_is_regular
 PURPOSE
    Check if a point selection is "regular"
 USAGE
    htri_t H5S_point_is_regular(space)
        const H5S_t *space;     IN: Dataspace pointer to check
 RETURNS
    TRUE/FALSE/FAIL
 DESCRIPTION
    Checks to see if the current selection in a dataspace is the a regular
    pattern.
    This is primarily used for reading the entire selection in one swoop.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
    Doesn't check for points selected to be next to one another in a regular
    pattern yet.
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static htri_t
H5S_point_is_regular(const H5S_t *space)
{
    htri_t ret_value; /* return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Check args */
    HDassert(space);

    /* Only simple check for regular points for now... */
    if (space->select.num_elem == 1)
        ret_value = TRUE;
    else
        ret_value = FALSE;

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_is_regular() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_adjust_u
 PURPOSE
    Adjust a "point" selection by subtracting an offset
 USAGE
    herr_t H5S_point_adjust_u(space, offset)
        H5S_t *space;           IN/OUT: Pointer to dataspace to adjust
        const hsize_t *offset; IN: Offset to subtract
 RETURNS
    Non-negative on success, negative on failure
 DESCRIPTION
    Moves a point selection by subtracting an offset from it.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_adjust_u(H5S_t *space, const hsize_t *offset)
{
    H5S_pnt_node_t *node; /* Point node */
    unsigned        rank; /* Dataspace rank */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(space);
    HDassert(offset);

    /* Iterate through the nodes, checking the bounds on each element */
    node = space->select.sel_info.pnt_lst->head;
    rank = space->extent.rank;
    while (node) {
        unsigned u; /* Local index variable */

        /* Adjust each coordinate for point node */
        for (u = 0; u < rank; u++) {
            /* Check for offset moving selection negative */
            HDassert(node->pnt[u] >= offset[u]);

            /* Adjust node's coordinate location */
            node->pnt[u] -= offset[u];
        } /* end for */

        /* Advance to next point node in selection */
        node = node->next;
    } /* end while */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5S_point_adjust_u() */

/*-------------------------------------------------------------------------
 * Function:    H5S_point_project_scalar
 *
 * Purpose:     Projects a single element point selection into a scalar
 *              dataspace
 *
 * Return:      Non-negative on success, negative on failure.
 *
 * Programmer:  Quincey Koziol
 *              Sunday, July 18, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5S_point_project_scalar(const H5S_t *space, hsize_t *offset)
{
    const H5S_pnt_node_t *node;                /* Point node */
    herr_t                ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    HDassert(space && H5S_SEL_POINTS == H5S_GET_SELECT_TYPE(space));
    HDassert(offset);

    /* Get the head of the point list */
    node = space->select.sel_info.pnt_lst->head;

    /* Check for more than one point selected */
    if (node->next)
        HGOTO_ERROR(H5E_DATASPACE, H5E_BADRANGE, FAIL,
                    "point selection of one element has more than one node!")

    /* Calculate offset of selection in projected buffer */
    *offset = H5VM_array_offset(space->extent.rank, space->extent.size, node->pnt);

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_project_scalar() */

/*-------------------------------------------------------------------------
 * Function:    H5S_point_project_simple
 *
 * Purpose:     Projects a point selection onto/into a simple dataspace
 *              of a different rank
 *
 * Return:      Non-negative on success, negative on failure.
 *
 * Programmer:  Quincey Koziol
 *              Sunday, July 18, 2010
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5S_point_project_simple(const H5S_t *base_space, H5S_t *new_space, hsize_t *offset)
{
    const H5S_pnt_node_t *base_node;           /* Point node in base space */
    H5S_pnt_node_t *      new_node;            /* Point node in new space */
    H5S_pnt_node_t *      prev_node;           /* Previous point node in new space */
    unsigned              rank_diff;           /* Difference in ranks between spaces */
    herr_t                ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    HDassert(base_space && H5S_SEL_POINTS == H5S_GET_SELECT_TYPE(base_space));
    HDassert(new_space);
    HDassert(offset);

    /* We are setting a new selection, remove any current selection in new dataspace */
    if (H5S_SELECT_RELEASE(new_space) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTDELETE, FAIL, "can't release selection")

    /* Allocate room for the head of the point list */
    if (NULL == (new_space->select.sel_info.pnt_lst = H5FL_MALLOC(H5S_pnt_list_t)))
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point list node")

    /* Check if the new space's rank is < or > base space's rank */
    if (new_space->extent.rank < base_space->extent.rank) {
        hsize_t block[H5S_MAX_RANK]; /* Block selected in base dataspace */

        /* Compute the difference in ranks */
        rank_diff = base_space->extent.rank - new_space->extent.rank;

        /* Calculate offset of selection in projected buffer */
        HDmemset(block, 0, sizeof(block));
        HDmemcpy(block, base_space->select.sel_info.pnt_lst->head->pnt, sizeof(hsize_t) * rank_diff);
        *offset = H5VM_array_offset(base_space->extent.rank, base_space->extent.size, block);

        /* Iterate through base space's point nodes, copying the point information */
        base_node = base_space->select.sel_info.pnt_lst->head;
        prev_node = NULL;
        while (base_node) {
            /* Create new point */
            if (NULL == (new_node = H5FL_MALLOC(H5S_pnt_node_t)))
                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point node")
            new_node->next = NULL;
            if (NULL == (new_node->pnt = (hsize_t *)H5MM_malloc(new_space->extent.rank * sizeof(hsize_t)))) {
                new_node = H5FL_FREE(H5S_pnt_node_t, new_node);
                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate coordinate information")
            } /* end if */

            /* Copy over the point's coordinates */
            HDmemcpy(new_node->pnt, &base_node->pnt[rank_diff], (new_space->extent.rank * sizeof(hsize_t)));

            /* Keep the order the same when copying */
            if (NULL == prev_node)
                prev_node = new_space->select.sel_info.pnt_lst->head = new_node;
            else {
                prev_node->next = new_node;
                prev_node       = new_node;
            } /* end else */

            /* Advance to next node */
            base_node = base_node->next;
        } /* end while */
    }     /* end if */
    else {
        HDassert(new_space->extent.rank > base_space->extent.rank);

        /* Compute the difference in ranks */
        rank_diff = new_space->extent.rank - base_space->extent.rank;

        /* The offset is zero when projected into higher dimensions */
        *offset = 0;

        /* Iterate through base space's point nodes, copying the point information */
        base_node = base_space->select.sel_info.pnt_lst->head;
        prev_node = NULL;
        while (base_node) {
            /* Create new point */
            if (NULL == (new_node = H5FL_MALLOC(H5S_pnt_node_t)))
                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate point node")
            new_node->next = NULL;
            if (NULL == (new_node->pnt = (hsize_t *)H5MM_malloc(new_space->extent.rank * sizeof(hsize_t)))) {
                new_node = H5FL_FREE(H5S_pnt_node_t, new_node);
                HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate coordinate information")
            } /* end if */

            /* Copy over the point's coordinates */
            HDmemset(new_node->pnt, 0, sizeof(hsize_t) * rank_diff);
            HDmemcpy(&new_node->pnt[rank_diff], base_node->pnt, (new_space->extent.rank * sizeof(hsize_t)));

            /* Keep the order the same when copying */
            if (NULL == prev_node)
                prev_node = new_space->select.sel_info.pnt_lst->head = new_node;
            else {
                prev_node->next = new_node;
                prev_node       = new_node;
            } /* end else */

            /* Advance to next node */
            base_node = base_node->next;
        } /* end while */
    }     /* end else */

    /* Clear cached iteration point */
    new_space->select.sel_info.pnt_lst->last_idx     = 0;
    new_space->select.sel_info.pnt_lst->last_idx_pnt = NULL;

    /* Number of elements selected will be the same */
    new_space->select.num_elem = base_space->select.num_elem;

    /* Set selection type */
    new_space->select.type = H5S_sel_point;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5S_point_project_simple() */

/*--------------------------------------------------------------------------
 NAME
    H5Sselect_elements
 PURPOSE
    Specify a series of elements in the dataspace to select
 USAGE
    herr_t H5Sselect_elements(dsid, op, num_elem, coord)
        hid_t dsid;             IN: Dataspace ID of selection to modify
        H5S_seloper_t op;       IN: Operation to perform on current selection
        size_t num_elem;        IN: Number of elements in COORD array.
        const hsize_t *coord;   IN: The location of each element selected
 RETURNS
    Non-negative on success/Negative on failure
 DESCRIPTION
    This function selects array elements to be included in the selection for
    the dataspace.  The COORD array is a 2-D array of size <dataspace rank>
    by NUM_ELEM (ie. a list of coordinates in the dataspace).  The order of
    the element coordinates in the COORD array specifies the order that the
    array elements are iterated through when I/O is performed.  Duplicate
    coordinates are not checked for.  The selection operator, OP, determines
    how the new selection is to be combined with the existing selection for
    the dataspace.  Currently, only H5S_SELECT_SET is supported, which replaces
    the existing selection with the one defined in this call.  When operators
    other than H5S_SELECT_SET are used to combine a new selection with an
    existing selection, the selection ordering is reset to 'C' array ordering.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
herr_t
H5Sselect_elements(hid_t spaceid, H5S_seloper_t op, size_t num_elem, const hsize_t *coord)
{
    H5S_t *space;     /* Dataspace to modify selection of */
    herr_t ret_value; /* Return value */

    FUNC_ENTER_API(FAIL)
    H5TRACE4("e", "iSsz*h", spaceid, op, num_elem, coord);

    /* Check args */
    if (NULL == (space = (H5S_t *)H5I_object_verify(spaceid, H5I_DATASPACE)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataspace")
    if (H5S_SCALAR == H5S_GET_EXTENT_TYPE(space))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "point doesn't support H5S_SCALAR space")
    if (H5S_NULL == H5S_GET_EXTENT_TYPE(space))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "point doesn't support H5S_NULL space")
    if (coord == NULL || num_elem == 0)
        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "elements not specified")
    if (!(op == H5S_SELECT_SET || op == H5S_SELECT_APPEND || op == H5S_SELECT_PREPEND))
        HGOTO_ERROR(H5E_ARGS, H5E_UNSUPPORTED, FAIL, "unsupported operation attempted")

    /* Call the real element selection routine */
    if ((ret_value = H5S_select_elements(space, op, num_elem, coord)) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTDELETE, FAIL, "can't select elements")

done:
    FUNC_LEAVE_API(ret_value)
} /* H5Sselect_elements() */

/*--------------------------------------------------------------------------
 NAME
    H5S_point_get_seq_list
 PURPOSE
    Create a list of offsets & lengths for a selection
 USAGE
    herr_t H5S_point_get_seq_list(space,flags,iter,maxseq,maxelem,nseq,nelem,off,len)
        H5S_t *space;           IN: Dataspace containing selection to use.
        unsigned flags;         IN: Flags for extra information about operation
        H5S_sel_iter_t *iter;   IN/OUT: Selection iterator describing last
                                    position of interest in selection.
        size_t maxseq;          IN: Maximum number of sequences to generate
        size_t maxelem;         IN: Maximum number of elements to include in the
                                    generated sequences
        size_t *nseq;           OUT: Actual number of sequences generated
        size_t *nelem;          OUT: Actual number of elements in sequences generated
        hsize_t *off;           OUT: Array of offsets
        size_t *len;            OUT: Array of lengths
 RETURNS
    Non-negative on success/Negative on failure.
 DESCRIPTION
    Use the selection in the dataspace to generate a list of byte offsets and
    lengths for the region(s) selected.  Start/Restart from the position in the
    ITER parameter.  The number of sequences generated is limited by the MAXSEQ
    parameter and the number of sequences actually generated is stored in the
    NSEQ parameter.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static herr_t
H5S_point_get_seq_list(const H5S_t *space, unsigned flags, H5S_sel_iter_t *iter, size_t maxseq,
                       size_t maxelem, size_t *nseq, size_t *nelem, hsize_t *off, size_t *len)
{
    size_t          io_left;                /* The number of bytes left in the selection */
    size_t          start_io_left;          /* The initial number of bytes left in the selection */
    H5S_pnt_node_t *node;                   /* Point node */
    hsize_t         dims[H5O_LAYOUT_NDIMS]; /* Total size of memory buf */
    int             ndims;                  /* Dimensionality of space*/
    hsize_t         acc;                    /* Coordinate accumulator */
    hsize_t         loc;                    /* Coordinate offset */
    size_t          curr_seq;               /* Current sequence being operated on */
    int             i;                      /* Local index variable */
    herr_t          ret_value = SUCCEED;    /* return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    HDassert(space);
    HDassert(iter);
    HDassert(maxseq > 0);
    HDassert(maxelem > 0);
    HDassert(nseq);
    HDassert(nelem);
    HDassert(off);
    HDassert(len);

    /* Choose the minimum number of bytes to sequence through */
    H5_CHECK_OVERFLOW(iter->elmt_left, hsize_t, size_t);
    start_io_left = io_left = (size_t)MIN(iter->elmt_left, maxelem);

    /* Get the dataspace dimensions */
    if ((ndims = H5S_get_simple_extent_dims(space, dims, NULL)) < 0)
        HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "unable to retrieve data space dimensions")

    /* Walk through the points in the selection, starting at the current */
    /*  location in the iterator */
    node     = iter->u.pnt.curr;
    curr_seq = 0;
    while (NULL != node) {
        /* Compute the offset of each selected point in the buffer */
        for (i = ndims - 1, acc = iter->elmt_size, loc = 0; i >= 0; i--) {
            loc += (node->pnt[i] + space->select.offset[i]) * acc;
            acc *= dims[i];
        } /* end for */

        /* Check if this is a later point in the selection */
        if (curr_seq > 0) {
            /* If a sorted sequence is requested, make certain we don't go backwards in the offset */
            if ((flags & H5S_GET_SEQ_LIST_SORTED) && loc < off[curr_seq - 1])
                break;

            /* Check if this point extends the previous sequence */
            /* (Unlikely, but possible) */
            if (loc == (off[curr_seq - 1] + len[curr_seq - 1])) {
                /* Extend the previous sequence */
                len[curr_seq - 1] += iter->elmt_size;
            } /* end if */
            else {
                /* Add a new sequence */
                off[curr_seq] = loc;
                len[curr_seq] = iter->elmt_size;

                /* Increment sequence count */
                curr_seq++;
            } /* end else */
        }     /* end if */
        else {
            /* Add a new sequence */
            off[curr_seq] = loc;
            len[curr_seq] = iter->elmt_size;

            /* Increment sequence count */
            curr_seq++;
        } /* end else */

        /* Decrement number of elements left to process */
        io_left--;

        /* Move the iterator */
        iter->u.pnt.curr = node->next;
        iter->elmt_left--;

        /* Check if we're finished with all sequences */
        if (curr_seq == maxseq)
            break;

        /* Check if we're finished with all the elements available */
        if (io_left == 0)
            break;

        /* Advance to the next point */
        node = node->next;
    } /* end while */

    /* Set the number of sequences generated */
    *nseq = curr_seq;

    /* Set the number of elements used */
    *nelem = start_io_left - io_left;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5S_point_get_seq_list() */