summaryrefslogtreecommitdiffstats
path: root/src/H5V.c
blob: e23af01ca2c0f476a604c1df28a11881060d40a7 (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
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
 * of the source code distribution tree; Copyright.html can be found at the  *
 * root level of an installed copy of the electronic HDF5 document set and   *
 * is linked from the top-level documents page.  It can also be found at     *
 * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
 * access to either file, you may request a copy from help@hdfgroup.org.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Programmer: Robb Matzke <matzke@llnl.gov>
 *	       Friday, October 10, 1997
 */


#include "H5private.h"
#include "H5Eprivate.h"
#include "H5Oprivate.h"
#include "H5Vprivate.h"

/* Local typedefs */
typedef struct H5V_memcpy_ud_t {
    unsigned char *dst;         /* Pointer to destination buffer */
    const unsigned char *src;   /* Pointer to source buffer */
} H5V_memcpy_ud_t;

/* Local macros */
#define H5V_HYPER_NDIMS H5O_LAYOUT_NDIMS

/* Local prototypes */
static void
H5V_stride_optimize1(unsigned *np/*in,out*/, hsize_t *elmt_size/*in,out*/,
		     const hsize_t *size, hsize_t *stride1);
static void
H5V_stride_optimize2(unsigned *np/*in,out*/, hsize_t *elmt_size/*in,out*/,
		     const hsize_t *size, hsize_t *stride1, hsize_t *stride2);
#ifdef LATER
static void
H5V_stride_copy2(hsize_t nelmts, hsize_t elmt_size,
     unsigned dst_n, const hsize_t *dst_size, const ssize_t *dst_stride, void *_dst,
     unsigned src_n, const hsize_t *src_size, const ssize_t *src_stride, const void *_src);
#endif /* LATER */


/*-------------------------------------------------------------------------
 * Function:	H5V_stride_optimize1
 *
 * Purpose:	Given a stride vector which references elements of the
 *		specified size, optimize the dimensionality, the stride
 *		vector, and the element size to minimize the dimensionality
 *		and the number of memory accesses.
 *
 *		All arguments are passed by reference and their values may be
 *		modified by this function.
 *
 * Return:	None
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static void
H5V_stride_optimize1(unsigned *np/*in,out*/, hsize_t *elmt_size/*in,out*/,
		     const hsize_t *size, hsize_t *stride1)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /*
     * This has to be true because if we optimize the dimensionality down to
     * zero we still must make one reference.
     */
    assert(1 == H5V_vector_reduce_product(0, NULL));

    /*
     * Combine adjacent memory accesses
     */
    while (*np && stride1[*np-1]>0 &&
           (hsize_t)(stride1[*np-1])==*elmt_size) {
        *elmt_size *= size[*np-1];
        if (--*np)
            stride1[*np-1] += size[*np] * stride1[*np];
    }

    FUNC_LEAVE_NOAPI_VOID
}


/*-------------------------------------------------------------------------
 * Function:	H5V_stride_optimize2
 *
 * Purpose:	Given two stride vectors which reference elements of the
 *		specified size, optimize the dimensionality, the stride
 *		vectors, and the element size to minimize the dimensionality
 *		and the number of memory accesses.
 *
 *		All arguments are passed by reference and their values may be
 *		modified by this function.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *              Unrolled loops for common cases
 *              Quincey Koziol
 *		?, ? ?, 2001?
 *
 *-------------------------------------------------------------------------
 */
static void
H5V_stride_optimize2(unsigned *np/*in,out*/, hsize_t *elmt_size/*in,out*/,
		     const hsize_t *size, hsize_t *stride1, hsize_t *stride2)
{
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /*
     * This has to be true because if we optimize the dimensionality down to
     * zero we still must make one reference.
     */
    assert(1 == H5V_vector_reduce_product(0, NULL));
    assert (*elmt_size>0);

    /*
     * Combine adjacent memory accesses
     */

    /* Unroll loop for common cases */
    switch(*np) {
        case 1: /* For 0-D datasets (dunno if this ever gets used...) */
            if(stride1[0] == *elmt_size && stride2[0] == *elmt_size) {
                *elmt_size *= size[0];
                --*np;  /* *np decrements to a value of 0 now */
            } /* end if */
            break;

        case 2: /* For 1-D datasets */
            if(stride1[1] == *elmt_size && stride2[1] == *elmt_size) {
                *elmt_size *= size[1];
                --*np;  /* *np decrements to a value of 1 now */
                stride1[0] += size[1] * stride1[1];
                stride2[0] += size[1] * stride2[1];

                if(stride1[0] == *elmt_size && stride2[0] == *elmt_size) {
                    *elmt_size *= size[0];
                    --*np;  /* *np decrements to a value of 0 now */
                } /* end if */
            } /* end if */
            break;

        case 3: /* For 2-D datasets */
            if(stride1[2] == *elmt_size && stride2[2] == *elmt_size) {
                *elmt_size *= size[2];
                --*np;  /* *np decrements to a value of 2 now */
                stride1[1] += size[2] * stride1[2];
                stride2[1] += size[2] * stride2[2];

                if(stride1[1] == *elmt_size && stride2[1] == *elmt_size) {
                    *elmt_size *= size[1];
                    --*np;  /* *np decrements to a value of 1 now */
                    stride1[0] += size[1] * stride1[1];
                    stride2[0] += size[1] * stride2[1];

                    if(stride1[0] == *elmt_size && stride2[0] == *elmt_size) {
                        *elmt_size *= size[0];
                        --*np;  /* *np decrements to a value of 0 now */
                    } /* end if */
                } /* end if */
            } /* end if */
            break;

        case 4: /* For 3-D datasets */
            if(stride1[3] == *elmt_size && stride2[3] == *elmt_size) {
                *elmt_size *= size[3];
                --*np;  /* *np decrements to a value of 3 now */
                stride1[2] += size[3] * stride1[3];
                stride2[2] += size[3] * stride2[3];

                if(stride1[2] == *elmt_size && stride2[2] == *elmt_size) {
                    *elmt_size *= size[2];
                    --*np;  /* *np decrements to a value of 2 now */
                    stride1[1] += size[2] * stride1[2];
                    stride2[1] += size[2] * stride2[2];

                    if(stride1[1] == *elmt_size && stride2[1] == *elmt_size) {
                        *elmt_size *= size[1];
                        --*np;  /* *np decrements to a value of 1 now */
                        stride1[0] += size[1] * stride1[1];
                        stride2[0] += size[1] * stride2[1];

                        if(stride1[0] == *elmt_size && stride2[0] == *elmt_size) {
                            *elmt_size *= size[0];
                            --*np;  /* *np decrements to a value of 0 now */
                        } /* end if */
                    } /* end if */
                } /* end if */
            } /* end if */
            break;

        default:
            while (*np &&
                    stride1[*np-1] == *elmt_size &&
                    stride2[*np-1] == *elmt_size) {
                *elmt_size *= size[*np-1];
                if (--*np) {
                    stride1[*np-1] += size[*np] * stride1[*np];
                    stride2[*np-1] += size[*np] * stride2[*np];
                }
            }
            break;
    } /* end switch */

    FUNC_LEAVE_NOAPI_VOID
}


/*-------------------------------------------------------------------------
 * Function:	H5V_hyper_stride
 *
 * Purpose:	Given a description of a hyperslab, this function returns
 *		(through STRIDE[]) the byte strides appropriate for accessing
 *		all bytes of the hyperslab and the byte offset where the
 *		striding will begin.  The SIZE can be passed to the various
 *		stride functions.
 *
 *		The dimensionality of the whole array, the hyperslab, and the
 *		returned stride array is N.  The whole array dimensions are
 *		TOTAL_SIZE and the hyperslab is at offset OFFSET and has
 *		dimensions SIZE.
 *
 *		The stride and starting point returned will cause the
 *		hyperslab elements to be referenced in C order.
 *
 * Return:	Success:	Byte offset from beginning of array to start
 *				of striding.
 *
 *		Failure:	abort() -- should never fail
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *              Unrolled loops for common cases
 *              Quincey Koziol
 *		?, ? ?, 2001?
 *
 *-------------------------------------------------------------------------
 */
hsize_t
H5V_hyper_stride(unsigned n, const hsize_t *size,
		 const hsize_t *total_size, const hsize_t *offset,
		 hsize_t *stride/*out*/)
{
    hsize_t	    skip;	/*starting point byte offset		*/
    hsize_t	    acc;	/*accumulator				*/
    int		i;		/*counter				*/
    hsize_t	    ret_value;  /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert(n <= H5V_HYPER_NDIMS);
    assert(size);
    assert(total_size);
    assert(stride);

    /* init */
    assert(n>0);
    stride[n-1] = 1;
    skip = offset ? offset[n-1] : 0;

    switch(n) {
        case 2: /* 1-D dataset */
            assert (total_size[1]>=size[1]);
            stride[0] = total_size[1]-size[1]; /*overflow checked*/
            acc = total_size[1];
            skip += acc * (offset ? offset[0] : 0);
            break;

        case 3: /* 2-D dataset */
            assert (total_size[2]>=size[2]);
            stride[1] = total_size[2]-size[2]; /*overflow checked*/
            acc = total_size[2];
            skip += acc * (offset ? (hsize_t)offset[1] : 0);

            assert (total_size[1]>=size[1]);
            stride[0] = acc * (total_size[1] - size[1]); /*overflow checked*/
            acc *= total_size[1];
            skip += acc * (offset ? (hsize_t)offset[0] : 0);
            break;

        case 4: /* 3-D dataset */
            assert (total_size[3]>=size[3]);
            stride[2] = total_size[3]-size[3]; /*overflow checked*/
            acc = total_size[3];
            skip += acc * (offset ? (hsize_t)offset[2] : 0);

            assert (total_size[2]>=size[2]);
            stride[1] = acc * (total_size[2] - size[2]); /*overflow checked*/
            acc *= total_size[2];
            skip += acc * (offset ? (hsize_t)offset[1] : 0);

            assert (total_size[1]>=size[1]);
            stride[0] = acc * (total_size[1] - size[1]); /*overflow checked*/
            acc *= total_size[1];
            skip += acc * (offset ? (hsize_t)offset[0] : 0);
            break;

        default:
            /* others */
            for (i=(int)(n-2), acc=1; i>=0; --i) {
                assert (total_size[i+1]>=size[i+1]);
                stride[i] = acc * (total_size[i+1] - size[i+1]); /*overflow checked*/
                acc *= total_size[i+1];
                skip += acc * (offset ? (hsize_t)offset[i] : 0);
            }
            break;
    } /* end switch */

    /* Set return value */
    ret_value=skip;

    FUNC_LEAVE_NOAPI(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_hyper_eq
 *
 * Purpose:	Determines whether two hyperslabs are equal.  This function
 *		assumes that both hyperslabs are relative to the same array,
 *		for if not, they could not possibly be equal.
 *
 * Return:	Success:	TRUE if the hyperslabs are equal (that is,
 *				both refer to exactly the same elements of an
 *				array)
 *
 *				FALSE otherwise.
 *
 *		Failure:	TRUE the rank is zero or if both hyperslabs
 *				are of zero size.
 *
 * Programmer:	Robb Matzke
 *		Friday, October 17, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
htri_t
H5V_hyper_eq(unsigned n,
	     const hsize_t *offset1, const hsize_t *size1,
	     const hsize_t *offset2, const hsize_t *size2)
{
    hsize_t	nelmts1 = 1, nelmts2 = 1;
    unsigned	i;
    htri_t      ret_value=TRUE;         /* Return value */

    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    if (n == 0) HGOTO_DONE(TRUE)

    for (i=0; i<n; i++) {
	if ((offset1 ? offset1[i] : 0) != (offset2 ? offset2[i] : 0))
	    HGOTO_DONE(FALSE)
	if ((size1 ? size1[i] : 0) != (size2 ? size2[i] : 0))
	    HGOTO_DONE(FALSE)
	if (0 == (nelmts1 *= (size1 ? size1[i] : 0)))
            HGOTO_DONE(FALSE)
	if (0 == (nelmts2 *= (size2 ? size2[i] : 0)))
            HGOTO_DONE(FALSE)
    }

done:
    FUNC_LEAVE_NOAPI(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_hyper_disjointp
 *
 * Purpose:	Determines if two hyperslabs are disjoint.
 *
 * Return:	Success:	FALSE if they are not disjoint.
 *				TRUE if they are disjoint.
 *
 *		Failure:	A hyperslab of zero size is disjoint from all
 *				other hyperslabs.
 *
 * Programmer:	Robb Matzke
 *		Thursday, October 16, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
htri_t
H5V_hyper_disjointp(unsigned n,
    const hsize_t *offset1, const uint32_t *size1,
    const hsize_t *offset2, const uint32_t *size2)
{
    unsigned	u;
    htri_t      ret_value = FALSE;        /* Return value */

    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    if(!n || !size1 || !size2)
        HGOTO_DONE(TRUE)

    for(u = 0; u < n; u++) {
        HDassert(size1[u] < HSIZET_MAX);
        HDassert(size2[u] < HSIZET_MAX);

        if(0 == size1[u] || 0 == size2[u])
            HGOTO_DONE(TRUE)
        if(((offset1 ? offset1[u] : 0) < (offset2 ? offset2[u] : 0) &&
                    ((offset1 ? offset1[u] : 0) + size1[u] <= (offset2 ? offset2[u] : 0))) ||
                ((offset2 ? offset2[u] : 0) < (offset1 ? offset1[u] : 0) &&
                    ((offset2 ? offset2[u] : 0) + size2[u] <= (offset1 ? offset1[u] : 0))))
            HGOTO_DONE(TRUE)
    } /* end for */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_hyper_disjointp() */


/*-------------------------------------------------------------------------
 * Function:	H5V_hyper_fill
 *
 * Purpose:	Similar to memset() except it operates on hyperslabs...
 *
 *		Fills a hyperslab of array BUF with some value VAL.  BUF
 *		is treated like a C-order array with N dimensions where the
 *		size of each dimension is TOTAL_SIZE[].	 The hyperslab which
 *		will be filled with VAL begins at byte offset OFFSET[] from
 *		the minimum corner of BUF and continues for SIZE[] bytes in
 *		each dimension.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Friday, October 10, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_hyper_fill(unsigned n, const hsize_t *_size,
	       const hsize_t *total_size, const hsize_t *offset, void *_dst,
	       unsigned fill_value)
{
    uint8_t	*dst = (uint8_t*)_dst;	/*cast for ptr arithmetic	*/
    hsize_t	size[H5V_HYPER_NDIMS];	/*a modifiable copy of _size	*/
    hsize_t	dst_stride[H5V_HYPER_NDIMS]; /*destination stride info  */
    hsize_t	dst_start;		/*byte offset to start of stride*/
    hsize_t	elmt_size = 1;		/*bytes per element		*/
    herr_t	ret_value;		/*function return status	*/
#ifndef NDEBUG
    unsigned	u;
#endif

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* check args */
    assert(n > 0 && n <= H5V_HYPER_NDIMS);
    assert(_size);
    assert(total_size);
    assert(dst);
#ifndef NDEBUG
    for (u = 0; u < n; u++) {
        assert(_size[u] > 0);
        assert(total_size[u] > 0);
    }
#endif

    /* Copy the size vector so we can modify it */
    H5V_vector_cpy(n, size, _size);

    /* Compute an optimal destination stride vector */
    dst_start = H5V_hyper_stride(n, size, total_size, offset, dst_stride);
    H5V_stride_optimize1(&n, &elmt_size, size, dst_stride);

    /* Copy */
    ret_value = H5V_stride_fill(n, elmt_size, size, dst_stride, dst+dst_start,
			     fill_value);

    FUNC_LEAVE_NOAPI(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_hyper_copy
 *
 * Purpose:	Copies a hyperslab from the source to the destination.
 *
 *		A hyperslab is a logically contiguous region of
 *		multi-dimensional size SIZE of an array whose dimensionality
 *		is N and whose total size is DST_TOTAL_SIZE or SRC_TOTAL_SIZE.
 *		The minimum corner of the hyperslab begins at a
 *		multi-dimensional offset from the minimum corner of the DST
 *		(destination) or SRC (source) array.  The sizes and offsets
 *		are assumed to be in C order, that is, the first size/offset
 *		varies the slowest while the last varies the fastest in the
 *		mapping from N-dimensional space to linear space.  This
 *		function assumes that the array elements are single bytes (if
 *		your array has multi-byte elements then add an additional
 *		dimension whose size is that of your element).
 *
 *		The SRC and DST array may be the same array, but the results
 *		are undefined if the source hyperslab overlaps the
 *		destination hyperslab.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Friday, October 10, 1997
 *
 * Modifications:
 *              Unrolled loops for common cases
 *              Quincey Koziol
 *		?, ? ?, 2001?
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_hyper_copy(unsigned n, const hsize_t *_size,

	       /*destination*/
	       const hsize_t *dst_size, const hsize_t *dst_offset,
	       void *_dst,

	       /*source*/
	       const hsize_t *src_size, const hsize_t *src_offset,
	       const void *_src)
{
    const uint8_t *src = (const uint8_t*)_src;	/*cast for ptr arithmtc */
    uint8_t	*dst = (uint8_t*) _dst;		/*cast for ptr arithmtc */
    hsize_t	size[H5V_HYPER_NDIMS];		/*a modifiable _size	*/
    hsize_t	src_stride[H5V_HYPER_NDIMS];	/*source stride info	*/
    hsize_t	dst_stride[H5V_HYPER_NDIMS];	/*dest stride info	*/
    hsize_t	dst_start, src_start;		/*offset to start at	*/
    hsize_t	elmt_size = 1;			/*element size in bytes */
    herr_t	ret_value;			/*return status		*/
#ifndef NDEBUG
    unsigned	u;
#endif

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* check args */
    assert(n > 0 && n <= H5V_HYPER_NDIMS);
    assert(_size);
    assert(dst_size);
    assert(src_size);
    assert(dst);
    assert(src);
#ifndef NDEBUG
    for (u = 0; u < n; u++) {
        assert(_size[u] > 0);
        assert(dst_size[u] > 0);
        assert(src_size[u] > 0);
    }
#endif

    /* Copy the size vector so we can modify it */
    H5V_vector_cpy(n, size, _size);

    /* Compute stride vectors for source and destination */
#ifdef NO_INLINED_CODE
    dst_start = H5V_hyper_stride(n, size, dst_size, dst_offset, dst_stride);
    src_start = H5V_hyper_stride(n, size, src_size, src_offset, src_stride);
#else /* NO_INLINED_CODE */
    /* in-line version of two calls to H5V_hyper_stride() */
    {
        hsize_t	    dst_acc;	/*accumulator				*/
        hsize_t	    src_acc;	/*accumulator				*/
        int        ii;		    /*counter				*/

        /* init */
        assert(n>0);
        dst_stride[n-1] = 1;
        src_stride[n-1] = 1;
        dst_start = dst_offset ? dst_offset[n-1] : 0;
        src_start = src_offset ? src_offset[n-1] : 0;

        /* Unroll loop for common cases */
        switch(n) {
            case 2:
                assert (dst_size[1]>=size[1]);
                assert (src_size[1]>=size[1]);
                dst_stride[0] = dst_size[1] - size[1]; /*overflow checked*/
                src_stride[0] = src_size[1] - size[1]; /*overflow checked*/
                dst_acc = dst_size[1];
                src_acc = src_size[1];
                dst_start += dst_acc * (dst_offset ? dst_offset[0] : 0);
                src_start += src_acc * (src_offset ? src_offset[0] : 0);
                break;

            case 3:
                assert (dst_size[2]>=size[2]);
                assert (src_size[2]>=size[2]);
                dst_stride[1] = dst_size[2] - size[2]; /*overflow checked*/
                src_stride[1] = src_size[2] - size[2]; /*overflow checked*/
                dst_acc = dst_size[2];
                src_acc = src_size[2];
                dst_start += dst_acc * (dst_offset ? dst_offset[1] : 0);
                src_start += src_acc * (src_offset ? src_offset[1] : 0);

                assert (dst_size[1]>=size[1]);
                assert (src_size[1]>=size[1]);
                dst_stride[0] = dst_acc * (dst_size[1] - size[1]); /*overflow checked*/
                src_stride[0] = src_acc * (src_size[1] - size[1]); /*overflow checked*/
                dst_acc *= dst_size[1];
                src_acc *= src_size[1];
                dst_start += dst_acc * (dst_offset ? dst_offset[0] : 0);
                src_start += src_acc * (src_offset ? src_offset[0] : 0);
                break;

            case 4:
                assert (dst_size[3]>=size[3]);
                assert (src_size[3]>=size[3]);
                dst_stride[2] = dst_size[3] - size[3]; /*overflow checked*/
                src_stride[2] = src_size[3] - size[3]; /*overflow checked*/
                dst_acc = dst_size[3];
                src_acc = src_size[3];
                dst_start += dst_acc * (dst_offset ? dst_offset[2] : 0);
                src_start += src_acc * (src_offset ? src_offset[2] : 0);

                assert (dst_size[2]>=size[2]);
                assert (src_size[2]>=size[2]);
                dst_stride[1] = dst_acc * (dst_size[2] - size[2]); /*overflow checked*/
                src_stride[1] = src_acc * (src_size[2] - size[2]); /*overflow checked*/
                dst_acc *= dst_size[2];
                src_acc *= src_size[2];
                dst_start += dst_acc * (dst_offset ? dst_offset[1] : 0);
                src_start += src_acc * (src_offset ? src_offset[1] : 0);

                assert (dst_size[1]>=size[1]);
                assert (src_size[1]>=size[1]);
                dst_stride[0] = dst_acc * (dst_size[1] - size[1]); /*overflow checked*/
                src_stride[0] = src_acc * (src_size[1] - size[1]); /*overflow checked*/
                dst_acc *= dst_size[1];
                src_acc *= src_size[1];
                dst_start += dst_acc * (dst_offset ? dst_offset[0] : 0);
                src_start += src_acc * (src_offset ? src_offset[0] : 0);
                break;

            default:
                /* others */
                for (ii=(int)(n-2), dst_acc=1, src_acc=1; ii>=0; --ii) {
                    assert (dst_size[ii+1]>=size[ii+1]);
                    assert (src_size[ii+1]>=size[ii+1]);
                    dst_stride[ii] = dst_acc * (dst_size[ii+1] - size[ii+1]); /*overflow checked*/
                    src_stride[ii] = src_acc * (src_size[ii+1] - size[ii+1]); /*overflow checked*/
                    dst_acc *= dst_size[ii+1];
                    src_acc *= src_size[ii+1];
                    dst_start += dst_acc * (dst_offset ? dst_offset[ii] : 0);
                    src_start += src_acc * (src_offset ? src_offset[ii] : 0);
                }
                break;
        } /* end switch */
    }
#endif /* NO_INLINED_CODE */

    /* Optimize the strides as a pair */
    H5V_stride_optimize2(&n, &elmt_size, size, dst_stride, src_stride);

    /* Perform the copy in terms of stride */
    ret_value = H5V_stride_copy(n, elmt_size, size,
             dst_stride, dst+dst_start, src_stride, src+src_start);

    FUNC_LEAVE_NOAPI(ret_value)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_stride_fill
 *
 * Purpose:	Fills all bytes of a hyperslab with the same value using
 *		memset().
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_stride_fill(unsigned n, hsize_t elmt_size, const hsize_t *size,
		const hsize_t *stride, void *_dst, unsigned fill_value)
{
    uint8_t	*dst = (uint8_t*)_dst; 	/*cast for ptr arithmetic	*/
    hsize_t	idx[H5V_HYPER_NDIMS]; 	/*1-origin indices		*/
    hsize_t	nelmts;			/*number of elements to fill	*/
    hsize_t	i;			/*counter			*/
    int	j;			/*counter			*/
    hbool_t	carry;			/*subtraction carray value	*/

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert (elmt_size < SIZET_MAX);

    H5V_vector_cpy(n, idx, size);
    nelmts = H5V_vector_reduce_product(n, size);
    for (i=0; i<nelmts; i++) {
        /* Copy an element */
        H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
        HDmemset(dst, (int)fill_value, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */

        /* Decrement indices and advance pointer */
        for (j=(int)(n-1), carry=TRUE; j>=0 && carry; --j) {
            dst += stride[j];

            if (--idx[j])
                carry = FALSE;
            else {
                assert(size);
                idx[j] = size[j];
            } /* end else */
        }
    }

    FUNC_LEAVE_NOAPI(SUCCEED)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_stride_copy
 *
 * Purpose:	Uses DST_STRIDE and SRC_STRIDE to advance through the arrays
 *		DST and SRC while copying bytes from SRC to DST.  This
 *		function minimizes the number of calls to memcpy() by
 *		combining various strides, but it will never touch memory
 *		outside the hyperslab defined by the strides.
 *
 * Note:	If the src_stride is all zero and elmt_size is one, then it's
 *		probably more efficient to use H5V_stride_fill() instead.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_stride_copy(unsigned n, hsize_t elmt_size, const hsize_t *size,
		const hsize_t *dst_stride, void *_dst,
		const hsize_t *src_stride, const void *_src)
{
    uint8_t	*dst = (uint8_t*)_dst;		/*cast for ptr arithmetic*/
    const uint8_t *src = (const uint8_t*) _src;	/*cast for ptr arithmetic*/
    hsize_t	idx[H5V_HYPER_NDIMS];		/*1-origin indices	*/
    hsize_t	nelmts;				/*num elements to copy	*/
    hsize_t	i;				/*counter		*/
    int	j;				/*counters		*/
    hbool_t	carry;				/*carray for subtraction*/

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert (elmt_size<SIZET_MAX);

    if (n) {
        H5V_vector_cpy(n, idx, size);
        nelmts = H5V_vector_reduce_product(n, size);
        for (i=0; i<nelmts; i++) {

            /* Copy an element */
            H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
            HDmemcpy(dst, src, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */

            /* Decrement indices and advance pointers */
            for (j=(int)(n-1), carry=TRUE; j>=0 && carry; --j) {
                src += src_stride[j];
                dst += dst_stride[j];

                if (--idx[j])
                    carry = FALSE;
                else {
                    assert(size);
                    idx[j] = size[j];
                }
            }
        }
    } else {
        H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
        HDmemcpy (dst, src, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */
    }

    FUNC_LEAVE_NOAPI(SUCCEED)
}


/*-------------------------------------------------------------------------
 * Function:	H5V_stride_copy_s
 *
 * Purpose:	Uses DST_STRIDE and SRC_STRIDE to advance through the arrays
 *		DST and SRC while copying bytes from SRC to DST.  This
 *		function minimizes the number of calls to memcpy() by
 *		combining various strides, but it will never touch memory
 *		outside the hyperslab defined by the strides.
 *
 * Note:	If the src_stride is all zero and elmt_size is one, then it's
 *		probably more efficient to use H5V_stride_fill() instead.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_stride_copy_s(unsigned n, hsize_t elmt_size, const hsize_t *size,
		const hssize_t *dst_stride, void *_dst,
		const hssize_t *src_stride, const void *_src)
{
    uint8_t	*dst = (uint8_t*)_dst;		/*cast for ptr arithmetic*/
    const uint8_t *src = (const uint8_t*) _src;	/*cast for ptr arithmetic*/
    hsize_t	idx[H5V_HYPER_NDIMS];		/*1-origin indices	*/
    hsize_t	nelmts;				/*num elements to copy	*/
    hsize_t	i;				/*counter		*/
    int	j;				/*counters		*/
    hbool_t	carry;				/*carray for subtraction*/

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert (elmt_size<SIZET_MAX);

    if (n) {
        H5V_vector_cpy(n, idx, size);
        nelmts = H5V_vector_reduce_product(n, size);
        for (i=0; i<nelmts; i++) {

            /* Copy an element */
            H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
            HDmemcpy(dst, src, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */

            /* Decrement indices and advance pointers */
            for (j=(int)(n-1), carry=TRUE; j>=0 && carry; --j) {
                src += src_stride[j];
                dst += dst_stride[j];

                if (--idx[j])
                    carry = FALSE;
                else {
                    assert(size);
                    idx[j] = size[j];
                }
            }
        }
    } else {
        H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
        HDmemcpy (dst, src, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */
    }

    FUNC_LEAVE_NOAPI(SUCCEED)
}

#ifdef LATER

/*-------------------------------------------------------------------------
 * Function:	H5V_stride_copy2
 *
 * Purpose:	Similar to H5V_stride_copy() except the source and
 *		destination each have their own dimensionality and size and
 *		we copy exactly NELMTS elements each of size ELMT_SIZE.	 The
 *		size counters wrap if NELMTS is more than a size counter.
 *
 * Return:	None
 *
 * Programmer:	Robb Matzke
 *		Saturday, October 11, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static void
H5V_stride_copy2(hsize_t nelmts, hsize_t elmt_size,

		 /* destination */
		 unsigned dst_n, const hsize_t *dst_size,
		 const hsize_t *dst_stride,
		 void *_dst,

		 /* source */
		 unsigned src_n, const hsize_t *src_size,
		 const hsize_t *src_stride,
		 const void *_src)
{
    uint8_t	*dst = (uint8_t *) _dst;
    const uint8_t *src = (const uint8_t *) _src;
    hsize_t	dst_idx[H5V_HYPER_NDIMS];
    hsize_t	src_idx[H5V_HYPER_NDIMS];
    hsize_t	i;              /* Local index variable */
    int		j;              /* Local index variable */
    hbool_t	carry;

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert (elmt_size < SIZET_MAX);
    assert(dst_n>0);
    assert(src_n>0);

    H5V_vector_cpy(dst_n, dst_idx, dst_size);
    H5V_vector_cpy(src_n, src_idx, src_size);

    for (i=0; i<nelmts; i++) {

	/* Copy an element */
        H5_CHECK_OVERFLOW(elmt_size,hsize_t,size_t);
	HDmemcpy(dst, src, (size_t)elmt_size); /*lint !e671 The elmt_size will be OK */

	/* Decrement indices and advance pointers */
	for (j=(int)(dst_n-1), carry=TRUE; j>=0 && carry; --j) {
	    dst += dst_stride[j];
	    if (--dst_idx[j])
                carry = FALSE;
	    else {
                assert(dst_size);
                dst_idx[j] = dst_size[j];
            } /* end else */
	}
	for (j=(int)(src_n-1), carry=TRUE; j>=0 && carry; --j) {
	    src += src_stride[j];
	    if (--src_idx[j])
                carry = FALSE;
	    else {
                assert(src_size);
                src_idx[j] = src_size[j];
            } /* end else */
	}
    }

    FUNC_LEAVE_NOAPI_VOID
}
#endif /* LATER */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_fill
 *
 * Purpose:	Fills all bytes of an array with the same value using
 *		memset(). Increases amount copied by power of two until the
 *		halfway point is crossed, then copies the rest in one swoop.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Thursday, June 18, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_array_fill(void *_dst, const void *src, size_t size, size_t count)
{
    size_t      copy_size;          /* size of the buffer to copy	*/
    size_t      copy_items;         /* number of items currently copying*/
    size_t      items_left;         /* number of items left to copy 	*/
    uint8_t     *dst=(uint8_t*)_dst;/* alias for pointer arithmetic	*/

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert (dst);
    assert (src);
    assert (size < SIZET_MAX && size > 0);
    assert (count < SIZET_MAX && count > 0);

    HDmemcpy(dst, src, size);   /* copy first item */

    /* Initialize counters, etc. while compensating for first element copied */
    copy_size = size;
    copy_items = 1;
    items_left = count - 1;
    dst += size;

    /* copy until we've copied at least half of the items */
    while (items_left >= copy_items)
    {
        HDmemcpy(dst, _dst, copy_size);   /* copy the current chunk */
        dst += copy_size;     /* move the offset for the next chunk */
        items_left -= copy_items;   /* decrement the number of items left */

        copy_size *= 2;     /* increase the size of the chunk to copy */
        copy_items *= 2;    /* increase the count of items we are copying */
    }   /* end while */
    if (items_left > 0)   /* if there are any items left to copy */
        HDmemcpy(dst, _dst, items_left * size);

    FUNC_LEAVE_NOAPI(SUCCEED)
}   /* H5V_array_fill() */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_down
 *
 * Purpose:	Given a set of dimension sizes, calculate the size of each
 *              "down" slice.  This is the size of the dimensions for all the
 *              dimensions below the current one, which is used for indexing
 *              offsets in this dimension.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Monday, April 28, 2003
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_array_down(unsigned n, const hsize_t *total_size, hsize_t *down)
{
    hsize_t	acc;	                /*accumulator			*/
    int	        i;		        /*counter			*/

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert(n <= H5V_HYPER_NDIMS);
    assert(total_size);
    assert(down);

    /* Build the sizes of each dimension in the array */
    /* (From fastest to slowest) */
    for(i=(int)(n-1),acc=1; i>=0; i--) {
        down[i]=acc;
        acc *= total_size[i];
    } /* end for */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5V_array_down() */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_offset_pre
 *
 * Purpose:	Given a coordinate description of a location in an array, this
 *      function returns the byte offset of the coordinate.
 *
 *		The dimensionality of the whole array, and the offset is N.
 *              The whole array dimensions are TOTAL_SIZE and the coordinate
 *              is at offset OFFSET.
 *
 * Return:	Success: Byte offset from beginning of array to element offset
 *		Failure: abort() -- should never fail
 *
 * Programmer:	Quincey Koziol
 *		Tuesday, June 22, 1999
 *
 * Modifications:
 *              Use precomputed accumulator array
 *              Quincey Koziol
 *		Saturday, April 26, 2003
 *
 *-------------------------------------------------------------------------
 */
hsize_t
H5V_array_offset_pre(unsigned n, const hsize_t *acc, const hsize_t *offset)
{
    int             i;		/*counter				*/
    hsize_t	    ret_value;  /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    assert(n <= H5V_HYPER_NDIMS);
    assert(acc);
    assert(offset);

    /* Compute offset in array */
    for (i=(int)(n-1), ret_value=0; i>=0; --i)
        ret_value += acc[i] * offset[i];

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_array_offset_pre() */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_offset
 *
 * Purpose:	Given a coordinate description of a location in an array, this
 *      function returns the byte offset of the coordinate.
 *
 *		The dimensionality of the whole array, and the offset is N.
 *              The whole array dimensions are TOTAL_SIZE and the coordinate
 *              is at offset OFFSET.
 *
 * Return:	Success: Byte offset from beginning of array to element offset
 *		Failure: abort() -- should never fail
 *
 * Programmer:	Quincey Koziol
 *		Tuesday, June 22, 1999
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
hsize_t
H5V_array_offset(unsigned n, const hsize_t *total_size, const hsize_t *offset)
{
    hsize_t	acc_arr[H5V_HYPER_NDIMS];	/* Accumulated size of down dimensions */
    hsize_t	ret_value;  /* Return value */

    FUNC_ENTER_NOAPI((HDabort(), 0)) /*lint !e527 Don't worry about unreachable statement */

    assert(n <= H5V_HYPER_NDIMS);
    assert(total_size);
    assert(offset);

    /* Build the sizes of each dimension in the array */
    if(H5V_array_down(n,total_size,acc_arr)<0)
        HGOTO_ERROR(H5E_INTERNAL, H5E_BADVALUE, UFAIL, "can't compute down sizes")

    /* Set return value */
    ret_value=H5V_array_offset_pre(n,acc_arr,offset);

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_array_offset() */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_calc_pre
 *
 * Purpose:	Given a linear offset in an array, the dimensions of that
 *              array and the pre-computed 'down' (accumulator) sizes, this
 *              function computes the coordinates of that offset in the array.
 *
 *		The dimensionality of the whole array, and the coordinates is N.
 *              The array dimensions are TOTAL_SIZE and the coordinates
 *              are returned in COORD.  The linear offset is in OFFSET.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Thursday, July 16, 2009
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_array_calc_pre(hsize_t offset, unsigned n, const hsize_t *down,
    hsize_t *coords)
{
    unsigned    u;                      /* Local index variable */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(n <= H5V_HYPER_NDIMS);
    HDassert(coords);

    /* Compute the coordinates from the offset */
    for(u = 0; u < n; u++) {
        coords[u] = offset / down[u];
        offset %= down[u];
    } /* end for */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5V_array_calc_pre() */


/*-------------------------------------------------------------------------
 * Function:	H5V_array_calc
 *
 * Purpose:	Given a linear offset in an array and the dimensions of that
 *              array, this function computes the coordinates of that offset
 *              in the array.
 *
 *		The dimensionality of the whole array, and the coordinates is N.
 *              The array dimensions are TOTAL_SIZE and the coordinates
 *              are returned in COORD.  The linear offset is in OFFSET.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Wednesday, April 16, 2003
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_array_calc(hsize_t offset, unsigned n, const hsize_t *total_size, hsize_t *coords)
{
    hsize_t	idx[H5V_HYPER_NDIMS];	/* Size of each dimension in bytes */
    herr_t      ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

    /* Sanity check */
    HDassert(n <= H5V_HYPER_NDIMS);
    HDassert(total_size);
    HDassert(coords);

    /* Build the sizes of each dimension in the array */
    if(H5V_array_down(n, total_size, idx) < 0)
        HGOTO_ERROR(H5E_INTERNAL, H5E_BADVALUE, FAIL, "can't compute down sizes")

    /* Compute the coordinates from the offset */
    if(H5V_array_calc_pre(offset, n, idx, coords) < 0)
        HGOTO_ERROR(H5E_INTERNAL, H5E_BADVALUE, FAIL, "can't compute coordinates")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_array_calc() */


/*-------------------------------------------------------------------------
 * Function:	H5V_chunk_index
 *
 * Purpose:	Given a coordinate offset (COORD), the size of each chunk
 *              (CHUNK), the number of chunks in each dimension (NCHUNKS)
 *              and the number of dimensions of all of these (NDIMS), calculate
 *              a "chunk index" for the chunk that the coordinate offset is
 *              located in.
 *
 *              The chunk index starts at 0 and increases according to the
 *              fastest changing dimension, then the next fastest, etc.
 *
 *              For example, with a 3x5 chunk size and 6 chunks in the fastest
 *              changing dimension and 3 chunks in the slowest changing
 *              dimension, the chunk indices are as follows:
 *
 *              +-----+-----+-----+-----+-----+-----+
 *              |     |     |     |     |     |     |
 *              |  0  |  1  |  2  |  3  |  4  |  5  |
 *              |     |     |     |     |     |     |
 *              +-----+-----+-----+-----+-----+-----+
 *              |     |     |     |     |     |     |
 *              |  6  |  7  |  8  |  9  | 10  | 11  |
 *              |     |     |     |     |     |     |
 *              +-----+-----+-----+-----+-----+-----+
 *              |     |     |     |     |     |     |
 *              | 12  | 13  | 14  | 15  | 16  | 17  |
 *              |     |     |     |     |     |     |
 *              +-----+-----+-----+-----+-----+-----+
 *
 *              The chunk index is placed in the CHUNK_IDX location for return
 *              from this function
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Monday, April 21, 2003
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5V_chunk_index(unsigned ndims, const hsize_t *coord, const uint32_t *chunk,
    const hsize_t *down_nchunks, hsize_t *chunk_idx)
{
    hsize_t	scaled_coord[H5V_HYPER_NDIMS];	/* Scaled, coordinates, in terms of chunks */
    unsigned    u;                      /* Local index variable */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    assert(ndims <= H5V_HYPER_NDIMS);
    assert(coord);
    assert(chunk);
    assert(chunk_idx);

    /* Compute the scaled coordinates for actual coordinates */
    for(u=0; u<ndims; u++)
        scaled_coord[u]=coord[u]/chunk[u];

    /* Compute the chunk index */
    *chunk_idx=H5V_array_offset_pre(ndims,down_nchunks,scaled_coord); /*lint !e772 scaled_coord will always be initialized */

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* end H5V_chunk_index() */


/*-------------------------------------------------------------------------
 * Function:	H5V_opvv
 *
 * Purpose:	Perform an operation on a source & destination sequences
 *		of offset/length pairs.  Each set of sequnces has an array
 *		of lengths, an array of offsets, the maximum number of
 *		sequences and the current sequence to start at in the sequence.
 *
 *              There may be different numbers of bytes in the source and
 *              destination sequences, the operation stops when either the
 *              source or destination sequence runs out of information.
 *
 * Note:	The algorithm in this routine is [basically] the same as for
 *		H5V_memcpyvv().  Changes should be made to both!
 *
 * Return:	Non-negative # of bytes operated on, on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Thursday, September 30, 2010
 *
 *-------------------------------------------------------------------------
 */
ssize_t
H5V_opvv(size_t dst_max_nseq, size_t *dst_curr_seq, size_t dst_len_arr[],
    hsize_t dst_off_arr[],
    size_t src_max_nseq, size_t *src_curr_seq, size_t src_len_arr[],
    hsize_t src_off_arr[],
    H5V_opvv_func_t op, void *op_data)
{
    hsize_t *max_dst_off_ptr, *max_src_off_ptr;  /* Pointers to max. source and destination offset locations */
    hsize_t *dst_off_ptr, *src_off_ptr; /* Pointers to source and destination offset arrays */
    size_t *dst_len_ptr, *src_len_ptr;  /* Pointers to source and destination length arrays */
    hsize_t tmp_dst_off, tmp_src_off;   /* Temporary source and destination offset values */
    size_t tmp_dst_len, tmp_src_len;    /* Temporary source and destination length values */
    size_t acc_len;             /* Accumulated length of sequences */
    ssize_t ret_value = 0;      /* Return value (Total size of sequence in bytes) */

    FUNC_ENTER_NOAPI(FAIL)

    /* Sanity check */
    HDassert(dst_curr_seq);
    HDassert(*dst_curr_seq < dst_max_nseq);
    HDassert(dst_len_arr);
    HDassert(dst_off_arr);
    HDassert(src_curr_seq);
    HDassert(*src_curr_seq < src_max_nseq);
    HDassert(src_len_arr);
    HDassert(src_off_arr);
    HDassert(op);

    /* Set initial offset & length pointers */
    dst_len_ptr = dst_len_arr + *dst_curr_seq;
    dst_off_ptr = dst_off_arr + *dst_curr_seq;
    src_len_ptr = src_len_arr + *src_curr_seq;
    src_off_ptr = src_off_arr + *src_curr_seq;

    /* Get temporary source & destination sequence offsets & lengths */
    tmp_dst_len = *dst_len_ptr;
    tmp_dst_off = *dst_off_ptr;
    tmp_src_len = *src_len_ptr;
    tmp_src_off = *src_off_ptr;

    /* Compute maximum offset pointer values */
    max_dst_off_ptr = dst_off_arr + dst_max_nseq;
    max_src_off_ptr = src_off_arr + src_max_nseq;

/* Work through the sequences */
/* (Choose smallest sequence available initially) */

    /* Source sequence is less than destination sequence */
    if(tmp_src_len < tmp_dst_len) {
src_smaller:
        acc_len = 0;
        do {
            /* Make operator callback */
            if((*op)(tmp_dst_off, tmp_src_off, tmp_src_len, op_data) < 0)
                HGOTO_ERROR(H5E_INTERNAL, H5E_CANTOPERATE, FAIL, "can't perform operation")

            /* Accumulate number of bytes copied */
            acc_len += tmp_src_len;

            /* Update destination length */
            tmp_dst_off += tmp_src_len;
            tmp_dst_len -= tmp_src_len;

            /* Advance source offset & check for being finished */
            src_off_ptr++;
            if(src_off_ptr >= max_src_off_ptr) {
                /* Roll accumulated changes into appropriate counters */
                *dst_off_ptr = tmp_dst_off;
                *dst_len_ptr = tmp_dst_len;

                /* Done with sequences */
                goto finished;
            } /* end if */
            tmp_src_off = *src_off_ptr;

            /* Update source information */
            src_len_ptr++;
            tmp_src_len = *src_len_ptr;
        } while(tmp_src_len < tmp_dst_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_dst_len < tmp_src_len)
            goto dst_smaller;
        else
            goto equal;
    } /* end if */
    /* Destination sequence is less than source sequence */
    else if(tmp_dst_len < tmp_src_len) {
dst_smaller:
        acc_len = 0;
        do {
            /* Make operator callback */
            if((*op)(tmp_dst_off, tmp_src_off, tmp_dst_len, op_data) < 0)
                HGOTO_ERROR(H5E_INTERNAL, H5E_CANTOPERATE, FAIL, "can't perform operation")

            /* Accumulate number of bytes copied */
            acc_len += tmp_dst_len;

            /* Update source length */
            tmp_src_off += tmp_dst_len;
            tmp_src_len -= tmp_dst_len;

            /* Advance destination offset & check for being finished */
            dst_off_ptr++;
            if(dst_off_ptr >= max_dst_off_ptr) {
                /* Roll accumulated changes into appropriate counters */
                *src_off_ptr = tmp_src_off;
                *src_len_ptr = tmp_src_len;

                /* Done with sequences */
                goto finished;
            } /* end if */
            tmp_dst_off = *dst_off_ptr;

            /* Update destination information */
            dst_len_ptr++;
            tmp_dst_len = *dst_len_ptr;
        } while(tmp_dst_len < tmp_src_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_src_len < tmp_dst_len)
            goto src_smaller;
        else
            goto equal;
    } /* end else-if */
    /* Destination sequence and source sequence are same length */
    else {
equal:
        acc_len = 0;
        do {
            /* Make operator callback */
            if((*op)(tmp_dst_off, tmp_src_off, tmp_dst_len, op_data) < 0)
                HGOTO_ERROR(H5E_INTERNAL, H5E_CANTOPERATE, FAIL, "can't perform operation")

            /* Accumulate number of bytes copied */
            acc_len += tmp_dst_len;

            /* Advance source & destination offset & check for being finished */
            src_off_ptr++;
            dst_off_ptr++;
            if(src_off_ptr >= max_src_off_ptr || dst_off_ptr >= max_dst_off_ptr)
                /* Done with sequences */
                goto finished;
            tmp_src_off = *src_off_ptr;
            tmp_dst_off = *dst_off_ptr;

            /* Update source information */
            src_len_ptr++;
            tmp_src_len = *src_len_ptr;

            /* Update destination information */
            dst_len_ptr++;
            tmp_dst_len = *dst_len_ptr;
        } while(tmp_dst_len == tmp_src_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_dst_len < tmp_src_len)
            goto dst_smaller;
        else
            goto src_smaller;
    } /* end else */

finished:
    /* Roll accumulated sequence lengths into return value */
    ret_value += (ssize_t)acc_len;

    /* Update current sequence vectors */
    *dst_curr_seq = (size_t)(dst_off_ptr - dst_off_arr);
    *src_curr_seq = (size_t)(src_off_ptr - src_off_arr);

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_opvv() */


/*-------------------------------------------------------------------------
 * Function:	H5V_memcpyvv
 *
 * Purpose:	Given source and destination buffers in memory (SRC & DST)
 *              copy sequences of from the source buffer into the destination
 *              buffer.  Each set of sequnces has an array of lengths, an
 *              array of offsets, the maximum number of sequences and the
 *              current sequence to start at in the sequence.
 *
 *              There may be different numbers of bytes in the source and
 *              destination sequences, data copying stops when either the
 *              source or destination buffer runs out of sequence information.
 *
 * Note:	The algorithm in this routine is [basically] the same as for
 *		H5V_opvv().  Changes should be made to both!
 *
 * Return:	Non-negative # of bytes copied on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Friday, May 2, 2003
 *
 *-------------------------------------------------------------------------
 */
ssize_t
H5V_memcpyvv(void *_dst,
    size_t dst_max_nseq, size_t *dst_curr_seq, size_t dst_len_arr[], hsize_t dst_off_arr[],
    const void *_src,
    size_t src_max_nseq, size_t *src_curr_seq, size_t src_len_arr[], hsize_t src_off_arr[])
{
    unsigned char *dst;         /* Destination buffer pointer */
    const unsigned char *src;   /* Source buffer pointer */
    hsize_t *max_dst_off_ptr, *max_src_off_ptr;  /* Pointers to max. source and destination offset locations */
    hsize_t *dst_off_ptr, *src_off_ptr;  /* Pointers to source and destination offset arrays */
    size_t *dst_len_ptr, *src_len_ptr;  /* Pointers to source and destination length arrays */
    size_t tmp_dst_len;         /* Temporary dest. length value */
    size_t tmp_src_len;         /* Temporary source length value */
    size_t acc_len;             /* Accumulated length of sequences */
    ssize_t ret_value = 0;      /* Return value (Total size of sequence in bytes) */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(_dst);
    HDassert(dst_curr_seq);
    HDassert(*dst_curr_seq < dst_max_nseq);
    HDassert(dst_len_arr);
    HDassert(dst_off_arr);
    HDassert(_src);
    HDassert(src_curr_seq);
    HDassert(*src_curr_seq < src_max_nseq);
    HDassert(src_len_arr);
    HDassert(src_off_arr);

    /* Set initial offset & length pointers */
    dst_len_ptr = dst_len_arr + *dst_curr_seq;
    dst_off_ptr = dst_off_arr + *dst_curr_seq;
    src_len_ptr = src_len_arr + *src_curr_seq;
    src_off_ptr = src_off_arr + *src_curr_seq;

    /* Get temporary source & destination sequence lengths */
    tmp_dst_len = *dst_len_ptr;
    tmp_src_len = *src_len_ptr;

    /* Compute maximum offset pointer values */
    max_dst_off_ptr = dst_off_arr + dst_max_nseq;
    max_src_off_ptr = src_off_arr + src_max_nseq;

    /* Compute buffer offsets */
    dst = (unsigned char *)_dst + *dst_off_ptr;
    src = (const unsigned char *)_src + *src_off_ptr;

/* Work through the sequences */
/* (Choose smallest sequence available initially) */

    /* Source sequence is less than destination sequence */
    if(tmp_src_len < tmp_dst_len) {
src_smaller:
        acc_len = 0;
        do {
            /* Copy data */
            HDmemcpy(dst, src, tmp_src_len);

            /* Accumulate number of bytes copied */
            acc_len += tmp_src_len;

            /* Update destination length */
            tmp_dst_len -= tmp_src_len;

            /* Advance source offset & check for being finished */
            src_off_ptr++;
            if(src_off_ptr >= max_src_off_ptr) {
                /* Roll accumulated changes into appropriate counters */
                *dst_off_ptr += acc_len;
                *dst_len_ptr = tmp_dst_len;

                /* Done with sequences */
                goto finished;
            } /* end if */

            /* Update destination pointer */
            dst += tmp_src_len;

            /* Update source information */
            src_len_ptr++;
            tmp_src_len = *src_len_ptr;
            src = (const unsigned char *)_src + *src_off_ptr;
        } while(tmp_src_len < tmp_dst_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_dst_len < tmp_src_len)
            goto dst_smaller;
        else
            goto equal;
    } /* end if */
    /* Destination sequence is less than source sequence */
    else if(tmp_dst_len < tmp_src_len) {
dst_smaller:
        acc_len = 0;
        do {
            /* Copy data */
            HDmemcpy(dst, src, tmp_dst_len);

            /* Accumulate number of bytes copied */
            acc_len += tmp_dst_len;

            /* Update source length */
            tmp_src_len -= tmp_dst_len;

            /* Advance destination offset & check for being finished */
            dst_off_ptr++;
            if(dst_off_ptr >= max_dst_off_ptr) {
                /* Roll accumulated changes into appropriate counters */
                *src_off_ptr += acc_len;
                *src_len_ptr = tmp_src_len;

                /* Done with sequences */
                goto finished;
            } /* end if */

            /* Update source pointer */
            src += tmp_dst_len;

            /* Update destination information */
            dst_len_ptr++;
            tmp_dst_len = *dst_len_ptr;
            dst = (unsigned char *)_dst + *dst_off_ptr;
        } while(tmp_dst_len < tmp_src_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_src_len < tmp_dst_len)
            goto src_smaller;
        else
            goto equal;
    } /* end else-if */
    /* Destination sequence and source sequence are same length */
    else {
equal:
        acc_len = 0;
        do {
            /* Copy data */
            HDmemcpy(dst, src, tmp_dst_len);

            /* Accumulate number of bytes copied */
            acc_len += tmp_dst_len;

            /* Advance source & destination offset & check for being finished */
            src_off_ptr++;
            dst_off_ptr++;
            if(src_off_ptr >= max_src_off_ptr || dst_off_ptr >= max_dst_off_ptr)
                /* Done with sequences */
                goto finished;

            /* Update source information */
            src_len_ptr++;
            tmp_src_len = *src_len_ptr;
            src = (const unsigned char *)_src + *src_off_ptr;

            /* Update destination information */
            dst_len_ptr++;
            tmp_dst_len = *dst_len_ptr;
            dst = (unsigned char *)_dst + *dst_off_ptr;
        } while(tmp_dst_len == tmp_src_len);

        /* Roll accumulated sequence lengths into return value */
        ret_value += (ssize_t)acc_len;

        /* Transition to next state */
        if(tmp_dst_len < tmp_src_len)
            goto dst_smaller;
        else
            goto src_smaller;
    } /* end else */

finished:
    /* Roll accumulated sequence lengths into return value */
    ret_value += (ssize_t)acc_len;

    /* Update current sequence vectors */
    *dst_curr_seq = (size_t)(dst_off_ptr - dst_off_arr);
    *src_curr_seq = (size_t)(src_off_ptr - src_off_arr);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5V_memcpyvv() */