summaryrefslogtreecommitdiffstats
path: root/tools/lib/h5diff.c
blob: dc32b9e233fce9a1231dc272ad3d80b5797662c1 (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
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include <stdlib.h>
#include "h5diff.h"
#include "H5private.h"
#include "ph5diff.h"

/*
 * Debug printf macros. The prefix allows output filtering by test scripts.
 */
#ifdef H5DIFF_DEBUG
#define h5diffdebug(x) fprintf(stderr, "h5diff debug: " x)
#define h5diffdebug2(x1, x2) fprintf(stderr, "h5diff debug: " x1, x2)
#define h5diffdebug3(x1, x2, x3) fprintf(stderr, "h5diff debug: " x1, x2, x3)
#define h5diffdebug4(x1, x2, x3, x4) fprintf(stderr, "h5diff debug: " x1, x2, x3, x4)
#define h5diffdebug5(x1, x2, x3, x4, x5) fprintf(stderr, "h5diff debug: " x1, x2, x3, x4, x5)
#else
#define h5diffdebug(x)
#define h5diffdebug2(x1, x2)
#define h5diffdebug3(x1, x2, x3)
#define h5diffdebug4(x1, x2, x3, x4)
#define h5diffdebug5(x1, x2, x3, x4, x5)
#endif


/*-------------------------------------------------------------------------
 * Function: print_objname
 *
 * Purpose: check if object name is to be printed, only when:
 *  1) verbose mode
 *  2) when diff was found (normal mode)
 *-------------------------------------------------------------------------
 */
int
print_objname (diff_opt_t * options, hsize_t nfound)
{
 return ((options->m_verbose || nfound) && !options->m_quiet) ? 1 : 0;
}

/*-------------------------------------------------------------------------
 * Function: do_print_objname
 *
 * Purpose: print object name 
 *
 *-------------------------------------------------------------------------
 */
void
do_print_objname (const char *OBJ, const char *path1, const char *path2)
{
    parallel_print("%-7s: <%s> and <%s>\n", OBJ, path1, path2);
}



#ifdef H5_HAVE_PARALLEL
/*-------------------------------------------------------------------------
 * Function: phdiff_dismiss_workers
 *
 * Purpose: tell all workers to end.
 *
 * Return: none
 *
 * Programmer: Albert Cheng
 *
 * Date: Feb 6, 2005
 *
 *-------------------------------------------------------------------------
 */
void phdiff_dismiss_workers(void)
{
 int i;
 for(i=1; i<g_nTasks; i++)
  MPI_Send(NULL, 0, MPI_BYTE, i, MPI_TAG_END, MPI_COMM_WORLD);
}


/*-------------------------------------------------------------------------
 * Function: print_manager_output
 *
 * Purpose: special function that prints any output accumulated by the
 *      manager task.
 *
 * Return: none
 *
 * Programmer: Leon Arber
 *
 * Date: Feb 7, 2005
 *
 *-------------------------------------------------------------------------
 */
void print_manager_output(void)
{
 /* If there was something we buffered, let's print it now */
 if( (outBuffOffset>0) && g_Parallel)
 {
  printf("%s", outBuff);

  if(overflow_file)
  {
   int     tmp;

   rewind(overflow_file);
   while((tmp = getc(overflow_file)) >= 0)
    putchar(tmp);

   fclose(overflow_file);
   overflow_file = NULL;
  }

  fflush(stdout);
  memset(outBuff, 0, OUTBUFF_SIZE);
  outBuffOffset = 0;
 }
 else if( (outBuffOffset>0) && !g_Parallel)
 {
  fprintf(stderr, "h5diff error: outBuffOffset>0, but we're not in parallel!\n");
 }
}

/*-------------------------------------------------------------------------
 * Function: print_incoming_data
 *
 * Purpose: special function that prints any output that has been sent to the manager
 *      and is currently sitting in the incoming message queue
 *
 * Return: none
 *
 * Programmer: Leon Arber
 *
 * Date: March 7, 2005
 *
 *-------------------------------------------------------------------------
 */

static void print_incoming_data(void)
{
 char data[PRINT_DATA_MAX_SIZE+1];
 int  incomingMessage;
 MPI_Status Status;

 do
 {
  MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_PRINT_DATA, MPI_COMM_WORLD, &incomingMessage, &Status);
  if(incomingMessage)
  {
   memset(data, 0, PRINT_DATA_MAX_SIZE+1);
   MPI_Recv(data, PRINT_DATA_MAX_SIZE, MPI_CHAR, Status.MPI_SOURCE, MPI_TAG_PRINT_DATA, MPI_COMM_WORLD, &Status);

   printf("%s", data);
  }
 } while(incomingMessage);
}
#endif

/*-------------------------------------------------------------------------
 * Function: h5diff
 *
 * Purpose: public function, can be called in an application program.
 *   return differences between 2 HDF5 files
 *
 * Return: Number of differences found.
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: October 22, 2003
 *
 *-------------------------------------------------------------------------
 */

hsize_t h5diff(const char *fname1,
               const char *fname2,
               const char *objname1,
               const char *objname2,
               diff_opt_t *options)
{
 int nobjects1, nobjects2;
 trav_info_t *info1 = NULL;
 trav_info_t *info2 = NULL;
 hid_t        file1_id=(-1), file2_id=(-1);
 char         filenames[2][1024];
 hsize_t      nfound = 0;

 memset(filenames, 0, 1024*2);

 if (options->m_quiet &&
  (options->m_verbose || options->m_report))
 {
  printf("Error: -q (quiet mode) cannot be added to verbose or report modes\n");
  options->err_stat=1;
  return 0;
 }

/*-------------------------------------------------------------------------
 * open the files first; if they are not valid, no point in continuing
 *-------------------------------------------------------------------------
 */

 /* disable error reporting */
 H5E_BEGIN_TRY
 {
  /* Open the files */
  if ((file1_id = H5Fopen (fname1, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0)
  {
   printf ("h5diff: <%s>: unable to open file\n", fname1);
   options->err_stat = 1;

#ifdef H5_HAVE_PARALLEL
   if(g_Parallel)
   {
    /* Let tasks know that they won't be needed */
    phdiff_dismiss_workers();
   }
#endif

   goto out;
  }
  if ((file2_id = H5Fopen (fname2, H5F_ACC_RDONLY, H5P_DEFAULT)) < 0)
  {
   printf ("h5diff: <%s>: unable to open file\n", fname2);
   options->err_stat = 1;

#ifdef H5_HAVE_PARALLEL
   if(g_Parallel)
   {
    /* Let tasks know that they won't be needed */
    phdiff_dismiss_workers();
   }
#endif

   goto out;
  }
  /* enable error reporting */
 }
 H5E_END_TRY;

/*-------------------------------------------------------------------------
 * get the number of objects in the files
 *-------------------------------------------------------------------------
 */
 nobjects1 = h5trav_getinfo (file1_id, NULL, 0);
 nobjects2 = h5trav_getinfo (file2_id, NULL, 0);

 if (nobjects1 < 0 || nobjects2 < 0)
 {
  printf ("Error: Could not get get file contents\n");
  options->err_stat = 1;
#ifdef H5_HAVE_PARALLEL
  if(g_Parallel)
  {
   /* Let tasks know that they won't be needed */
   phdiff_dismiss_workers();
  }
#endif
  goto out;
 }

/*-------------------------------------------------------------------------
 * get the list of objects in the files
 *-------------------------------------------------------------------------
 */

 info1 = (trav_info_t *) malloc (nobjects1 * sizeof (trav_info_t));
 info2 = (trav_info_t *) malloc (nobjects2 * sizeof (trav_info_t));
 if (info1 == NULL || info2 == NULL)
 {
  printf ("Error: Not enough memory for object list\n");
  options->err_stat = 1;
  if (info1) h5trav_freeinfo (info1, nobjects1);
  if (info2) h5trav_freeinfo (info2, nobjects1);
#ifdef H5_HAVE_PARALLEL
  if(g_Parallel)
  {
   /* Let tasks know that they won't be needed */
   phdiff_dismiss_workers();
  }
#endif
  goto out;
 }

 h5trav_getinfo (file1_id, info1, 0);
 h5trav_getinfo (file2_id, info2, 0);

/*-------------------------------------------------------------------------
 * object name was supplied
 *-------------------------------------------------------------------------
 */

 if (objname1)
 {

#ifdef H5_HAVE_PARALLEL
  if(g_Parallel)
  {
   /* Let tasks know that they won't be needed */
   phdiff_dismiss_workers();
  }
#endif
  assert (objname2);
  options->cmn_objs = 1; /* eliminate warning */
  nfound = diff_compare (file1_id, fname1, objname1, nobjects1, info1,
   file2_id, fname2, objname2, nobjects2, info2,
   options);
 }

/*-------------------------------------------------------------------------
 * compare all
 *-------------------------------------------------------------------------
 */

 else
 {

#ifdef H5_HAVE_PARALLEL
  if(g_Parallel)
  {
   int i;

   if(  (strlen(fname1) > 1024) || (strlen(fname2) > 1024))
   {
    fprintf(stderr, "The parallel diff only supports path names up to 1024 characters\n");
    MPI_Abort(MPI_COMM_WORLD, 0);
   }

   strcpy(filenames[0], fname1);
   strcpy(filenames[1], fname2);

   /* Alert the worker tasks that there's going to be work. */

   for(i=1; i<g_nTasks; i++)
    MPI_Send(filenames, 1024*2, MPI_CHAR, i, MPI_TAG_PARALLEL, MPI_COMM_WORLD);
  }
#endif
  nfound = diff_match (file1_id, nobjects1, info1,
   file2_id, nobjects2, info2, options);
 }

 h5trav_freeinfo (info1, nobjects1);
 h5trav_freeinfo (info2, nobjects2);

out:
 /* close */
 H5E_BEGIN_TRY
 {
  H5Fclose (file1_id);
  H5Fclose (file2_id);
 }
 H5E_END_TRY;

 return nfound;
}



/*-------------------------------------------------------------------------
 * Function: diff_match
 *
 * Purpose: Find common objects; the algorithm used for this search is the
 *  cosequential match algorithm and is described in
 *  Folk, Michael; Zoellick, Bill. (1992). File Structures. Addison-Wesley.
 *
 * Return: Number of differences found
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: May 9, 2003
 *
 * Modifications: Jan 2005 Leon Arber, larber@uiuc.edu
 *    Added support for parallel diffing
 *
 *-------------------------------------------------------------------------
 */
hsize_t diff_match (hid_t file1_id,
                    int nobjects1,
                    trav_info_t * info1,
                    hid_t file2_id,
                    int nobjects2,
                    trav_info_t * info2,
                    diff_opt_t * options)
{
 int more_names_exist = (nobjects1 > 0 && nobjects2 > 0) ? 1 : 0;
 trav_table_t *table = NULL;
 int cmp;
 int curr1 = 0;
 int curr2 = 0;
 unsigned infile[2];
 char c1, c2;
 hsize_t nfound = 0;
 unsigned i;

/*-------------------------------------------------------------------------
 * build the list
 *-------------------------------------------------------------------------
 */
 trav_table_init (&table);

 while (more_names_exist)
 {
  /* criteria is string compare */
  cmp = strcmp (info1[curr1].name, info2[curr2].name);
  if (cmp == 0)
  {
   infile[0] = 1;
   infile[1] = 1;
   trav_table_addflags (infile, info1[curr1].name, info1[curr1].type,
    table);

   curr1++;
   curr2++;
  }
  else if (cmp < 0)
  {
   infile[0] = 1;
   infile[1] = 0;
   trav_table_addflags (infile, info1[curr1].name, info1[curr1].type,
    table);
   curr1++;
  }
  else
  {
   infile[0] = 0;
   infile[1] = 1;
   trav_table_addflags (infile, info2[curr2].name, info2[curr2].type,
    table);
   curr2++;
  }

  more_names_exist = (curr1 < nobjects1 && curr2 < nobjects2) ? 1 : 0;


 }    /* end while */

 /* list1 did not end */
 if (curr1 < nobjects1)
 {
  while (curr1 < nobjects1)
  {
   infile[0] = 1;
   infile[1] = 0;
   trav_table_addflags (infile, info1[curr1].name, info1[curr1].type,
    table);
   curr1++;
  }
 }

 /* list2 did not end */
 if (curr2 < nobjects2)
 {
  while (curr2 < nobjects2)
  {
   infile[0] = 0;
   infile[1] = 1;
   trav_table_addflags (infile, info2[curr2].name, info2[curr2].type,
    table);
   curr2++;
  }
 }

/*-------------------------------------------------------------------------
 * print the list
 *-------------------------------------------------------------------------
 */

 if (options->m_verbose)
 {
  printf ("\n");
  printf ("file1     file2\n");
  printf ("---------------------------------------\n");
  for (i = 0; i < table->nobjs; i++)
  {
   c1 = (table->objs[i].flags[0]) ? 'x' : ' ';
   c2 = (table->objs[i].flags[1]) ? 'x' : ' ';
   printf ("%5c %6c    %-15s\n", c1, c2, table->objs[i].name);
  }
  printf ("\n");
 }


/*-------------------------------------------------------------------------
 * do the diff for common objects
 *-------------------------------------------------------------------------
 */
 {
#ifdef H5_HAVE_PARALLEL
  char* workerTasks = malloc((g_nTasks-1) * sizeof(char));
  int n;
  int busyTasks=0;
  struct diffs_found nFoundbyWorker;
  struct diff_args args;
  int havePrintToken = 1;
  MPI_Status Status;

  /*set all tasks as free */
  memset(workerTasks, 1, g_nTasks-1);
#endif

  for (i = 0; i < table->nobjs; i++)
  {
   if (table->objs[i].flags[0] && table->objs[i].flags[1])
   {
#ifdef H5_HAVE_PARALLEL
    int workerFound = 0;
#endif /* H5_HAVE_PARALLEL */
    options->cmn_objs = 1;
    if(!g_Parallel)
    {
     nfound += diff (file1_id,
      table->objs[i].name,
      file2_id,
      table->objs[i].name, options, table->objs[i].type);
    }
#ifdef H5_HAVE_PARALLEL
    else
    {
     h5diffdebug("beginning of big else block\n");
     /* We're in parallel mode */
     /* Since the data type of diff value is hsize_t which can
     * be arbitary large such that there is no MPI type that
     * matches it, the value is passed between processes as
     * an array of bytes in order to be portable.  But this
     * may not work in non-homogeneous MPI environments.
     */

     /*Set up args to pass to worker task. */
     if(strlen(table->objs[i].name) > 255)
     {
      printf("The parallel diff only supports object names up to 255 characters\n");
      MPI_Abort(MPI_COMM_WORLD, 0);
     }

     strcpy(args.name, table->objs[i].name);
     args.options = *options;
     args.type= table->objs[i].type;

     h5diffdebug2("busyTasks=%d\n", busyTasks);
     /* if there are any outstanding print requests, let's handle one. */
     if(busyTasks > 0)
     {
      int incomingMessage;
      /* check if any tasks freed up, and didn't need to print. */
      MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &incomingMessage, &Status);

      /* first block*/
      if(incomingMessage)
      {
       workerTasks[Status.MPI_SOURCE-1] = 1;
       MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
       nfound += nFoundbyWorker.nfound;
       options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
       busyTasks--;
      }

      /* check to see if the print token was returned. */
      if(!havePrintToken)
      {
       /* If we don't have the token, someone is probably sending us output */
       print_incoming_data();

       /* check incoming queue for token */
       MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);

       /* incoming token implies free task. */
       if(incomingMessage)
       {
        workerTasks[Status.MPI_SOURCE-1] = 1;
        MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
        nfound += nFoundbyWorker.nfound;
        options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
        busyTasks--;
        havePrintToken = 1;
       }
      }

      /* check to see if anyone needs the print token. */
      if(havePrintToken)
      {
       /* check incoming queue for print token requests */
       MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &incomingMessage, &Status);
       if(incomingMessage)
       {
        MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
        MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
        havePrintToken = 0;
       }
      }
     }

     /* check array of tasks to see which ones are free.
     * Manager task never does work, so freeTasks[0] is really
     * worker task 0. */

     for(n=1; (n<g_nTasks) && !workerFound; n++)
     {
      if(workerTasks[n-1])
      {
       /* send file id's and names to first free worker */
       MPI_Send(&args, sizeof(struct diff_args), MPI_BYTE, n, MPI_TAG_ARGS, MPI_COMM_WORLD);

       /* increment counter for total number of prints. */
       busyTasks++;

       /* mark worker as busy */
       workerTasks[n-1] = 0;
       workerFound = 1;
      }

     }


     h5diffdebug2("workerfound is %d \n", workerFound);
     if(!workerFound)
     {
     /* if they were all busy, we've got to wait for one free up before we can move on.
      * if we don't have the token, some task is currently printing so we'll wait for that task to return it. */

      if(!havePrintToken)
      {
       while(!havePrintToken) {
        int incomingMessage;
        print_incoming_data();
        MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);
        if(incomingMessage)
        {
         MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
         havePrintToken = 1;
         nfound += nFoundbyWorker.nfound;
         options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
         /* send this task the work unit. */
         MPI_Send(&args, sizeof(struct diff_args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
        }
       }
      }
      /* if we do have the token, check for task to free up, or wait for a task to request it */
      else
      {
       /* But first print all the data in our incoming queue */
       print_incoming_data();
       MPI_Probe(MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &Status);
       if(Status.MPI_TAG == MPI_TAG_DONE)
       {
        MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
        nfound += nFoundbyWorker.nfound;
        options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
        MPI_Send(&args, sizeof(struct diff_args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
       }
       else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST)
       {
        int incomingMessage;
        MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
        MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);

        do
        {
         MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);

         print_incoming_data();
        }
        while(!incomingMessage);


        MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
        nfound += nFoundbyWorker.nfound;
        options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
        MPI_Send(&args, sizeof(struct diff_args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
       }
       else
       {
        printf("ERROR: Invalid tag (%d) received \n", Status.MPI_TAG);
        MPI_Abort(MPI_COMM_WORLD, 0);
        MPI_Finalize();
       }
      }
     }
  }
#endif /* H5_HAVE_PARALLEL */
     }
 }
 h5diffdebug("done with for loop\n");

#ifdef H5_HAVE_PARALLEL
 if(g_Parallel)
 {
  while(busyTasks > 0) /* make sure all tasks are done */
  {
   MPI_Probe(MPI_ANY_SOURCE, MPI_ANY_TAG, MPI_COMM_WORLD, &Status);
   if(Status.MPI_TAG == MPI_TAG_DONE)
   {
    MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
    nfound += nFoundbyWorker.nfound;
    options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
    busyTasks--;
   }
   else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN)
   {
    MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_DONE, MPI_COMM_WORLD, &Status);
    nfound += nFoundbyWorker.nfound;
    options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
    busyTasks--;
    havePrintToken = 1;
   }
   else if(Status.MPI_TAG == MPI_TAG_TOK_REQUEST)
   {
    MPI_Recv(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_REQUEST, MPI_COMM_WORLD, &Status);
    if(havePrintToken)
    {
     int incomingMessage;
     MPI_Send(NULL, 0, MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
     do
     {
      MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);

      print_incoming_data();
     }
     while(!incomingMessage);
     MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
     nfound += nFoundbyWorker.nfound;
     options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
     busyTasks--;
    }
    else /* someone else must have it...wait for them to return it, then give it to the task that just asked for it. */
    {
     int source = Status.MPI_SOURCE;
     int incomingMessage;
     do
     {
      MPI_Iprobe(MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &incomingMessage, &Status);

      print_incoming_data();
     }
     while(!incomingMessage);


     MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, MPI_ANY_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
     nfound += nFoundbyWorker.nfound;
     options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
     busyTasks--;
     MPI_Send(NULL, 0, MPI_BYTE, source, MPI_TAG_PRINT_TOK, MPI_COMM_WORLD);
    }
   }
   else if(Status.MPI_TAG == MPI_TAG_TOK_RETURN)
   {
    MPI_Recv(&nFoundbyWorker, sizeof(nFoundbyWorker), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_TOK_RETURN, MPI_COMM_WORLD, &Status);
    nfound += nFoundbyWorker.nfound;
    options->not_cmp = options->not_cmp | nFoundbyWorker.not_cmp;
    busyTasks--;
    havePrintToken = 1;
   }
   else if(Status.MPI_TAG == MPI_TAG_PRINT_DATA)
   {
    char  data[PRINT_DATA_MAX_SIZE+1];
    memset(data, 0, PRINT_DATA_MAX_SIZE+1);

    MPI_Recv(data, PRINT_DATA_MAX_SIZE, MPI_CHAR, Status.MPI_SOURCE, MPI_TAG_PRINT_DATA, MPI_COMM_WORLD, &Status);

    printf("%s", data);
   }
   else
   {
    printf("ph5diff-manager: ERROR!! Invalid tag (%d) received \n", Status.MPI_TAG);
    MPI_Abort(MPI_COMM_WORLD, 0);
   }
  }

  for(i=1; i<g_nTasks; i++)
   MPI_Send(NULL, 0, MPI_BYTE, i, MPI_TAG_END, MPI_COMM_WORLD);

  /* Print any final data waiting in our queue */
  print_incoming_data();

 }
 h5diffdebug("done with if block\n");

 free(workerTasks);
#endif /* H5_HAVE_PARALLEL */
 }

 /* free table */
 trav_table_free (table);


/*-------------------------------------------------------------------------
 * do the diff for the root.
 * this is a special case, we get an ID for the root group and call diff()
 * with this ID; it compares only the root group attributes
 *-------------------------------------------------------------------------
 */

 /* the manager can do this. */
 nfound += diff (file1_id, "/", file2_id, "/", options, H5G_GROUP);

 return nfound;
}


/*-------------------------------------------------------------------------
 * Function: diff_compare
 *
 * Purpose: get objects from list, and check for the same type
 *
 * Return: Number of differences found
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: May 9, 2003
 *
 *-------------------------------------------------------------------------
 */

hsize_t diff_compare (hid_t file1_id,
                      const char *file1_name,
                      const char *obj1_name,
                      int nobjects1,
                      trav_info_t * info1,
                      hid_t file2_id,
                      const char *file2_name,
                      const char *obj2_name,
                      int nobjects2,
                      trav_info_t * info2,
                      diff_opt_t * options)
{
 int f1 = 0, f2 = 0;
 hsize_t nfound = 0;

 int i = h5trav_getindex (obj1_name, nobjects1, info1);
 int j = h5trav_getindex (obj2_name, nobjects2, info2);

 if (i == -1)
 {
  parallel_print ("Object <%s> could not be found in <%s>\n", obj1_name,
   file1_name);
  f1 = 1;
 }
 if (j == -1)
 {
  parallel_print ("Object <%s> could not be found in <%s>\n", obj2_name,
   file2_name);
  f2 = 1;
 }
 if (f1 || f2)
 {
  options->err_stat = 1;
  return 0;
 }

 /* use the name with "/" first, as obtained by iterator function */
 obj1_name = info1[i].name;
 obj2_name = info2[j].name;

 /* objects are not the same type */
 if (info1[i].type != info2[j].type)
 {
  if (options->m_verbose)
   parallel_print
   ("Comparison not possible: <%s> is of type %s and <%s> is of type %s\n",
   obj1_name, get_type (info1[i].type), obj2_name,
   get_type (info2[j].type));
  options->not_cmp=1;
  return 0;
 }

 nfound =
  diff (file1_id, obj1_name, file2_id, obj2_name, options, info1[i].type);

 return nfound;
}


/*-------------------------------------------------------------------------
 * Function: diff
 *
 * Purpose: switch between types and choose the diff function
 * TYPE is either
 *  H5G_GROUP         Object is a group
 *  H5G_DATASET       Object is a dataset
 *  H5G_TYPE          Object is a named data type
 *  H5G_LINK          Object is a symbolic link
 *
 * Return: Number of differences found
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: May 9, 2003
 *
 *-------------------------------------------------------------------------
 */

hsize_t diff (hid_t file1_id,
              const char *path1,
              hid_t file2_id, 
              const char *path2, 
              diff_opt_t * options, 
              H5G_obj_t1 type)
{
    hid_t       type1_id=(-1);
    hid_t       type2_id=(-1);
    hid_t       grp1_id=(-1);
    hid_t       grp2_id=(-1);
    int ret;
    H5G_stat_t sb1;
    H5G_stat_t sb2;
    hsize_t nfound = 0;
    
    switch (type)
    {
    
   /*-------------------------------------------------------------------------
    * H5G_DATASET
    *-------------------------------------------------------------------------
    */
    case H5G_DATASET:
        
       /*-------------------------------------------------------------------------
        * verbose, always print name
        *-------------------------------------------------------------------------
        */
        if (options->m_verbose)
        {
            if (print_objname(options,(hsize_t)1))
                do_print_objname ("dataset", path1, path2);
            nfound=diff_dataset(file1_id,file2_id,path1,path2,options);
            print_found(nfound);
            
        }
       /*-------------------------------------------------------------------------
        * non verbose, check first if we have differences by enabling quiet mode
        * so that printing is off, and compare again if differences found,
        * disabling quite mode
        *-------------------------------------------------------------------------
        */
        else
        {
            if (options->m_quiet==0)
            {
                /* shut up temporarily */
                options->m_quiet=1;
                nfound=diff_dataset(file1_id,file2_id,path1,path2,options);
                /* print again */
                options->m_quiet=0;
                if (nfound)
                {
                    if (print_objname(options,nfound))
                        do_print_objname ("dataset", path1, path2);
                    nfound=diff_dataset(file1_id,file2_id,path1,path2,options);
                    print_found(nfound);
                } 
            } 
            /* in quiet mode, just count differences */
            else
            {
                nfound=diff_dataset(file1_id,file2_id,path1,path2,options);
            }
        }
        
        break;
        
   /*-------------------------------------------------------------------------
    * H5G_TYPE
    *-------------------------------------------------------------------------
    */
    case H5G_TYPE:

        if ((type1_id = H5Topen(file1_id, path1))<0)
            goto out;
        if ((type2_id = H5Topen(file2_id, path2))<0)
            goto out;
        
        if ((ret = H5Tequal(type1_id,type2_id))<0)
            goto out;
        
        /* if H5Tequal is > 0 then the datatypes refer to the same datatype */
        nfound = (ret>0) ? 0 : 1;
        
        if (print_objname(options,nfound))
            do_print_objname ("datatype", path1, path2);

        /* always print the number of differences found in verbose mode */
        if (options->m_verbose)
            print_found(nfound);
        
        /*-------------------------------------------------------------------------
         * compare attributes
         * the if condition refers to cases when the dataset is a referenced object
         *-------------------------------------------------------------------------
         */
        if (path1)
            nfound += diff_attr(type1_id,type2_id,path1,path2,options);
        
        if ( H5Tclose(type1_id)<0)
            goto out;
        if ( H5Tclose(type2_id)<0)
            goto out;
        
        break;
        
   /*-------------------------------------------------------------------------
    * H5G_GROUP
    *-------------------------------------------------------------------------
    */
    case H5G_GROUP:

        ret = HDstrcmp(path1, path2);
    
        /* if "path1" != "path2" then the groups are "different" */
        nfound = (ret != 0) ? 1 : 0;
        
        if(print_objname(options, nfound))
            do_print_objname("group", path1, path2);

        /* always print the number of differences found in verbose mode */
        if(options->m_verbose)
            print_found(nfound);
        
        if((grp1_id = H5Gopen2(file1_id, path1, H5P_DEFAULT)) < 0)
            goto out;
        if((grp2_id = H5Gopen2(file2_id, path2, H5P_DEFAULT)) < 0)
            goto out;

        /*-------------------------------------------------------------------------
         * compare attributes
         * the if condition refers to cases when the dataset is a referenced object
         *-------------------------------------------------------------------------
         */
        if(path1)
            nfound += diff_attr(grp1_id, grp2_id, path1, path2, options);
        
        if(H5Gclose(grp1_id) < 0)
            goto out;
        if(H5Gclose(grp2_id) < 0)
            goto out;
        
        break;
        
        
   /*-------------------------------------------------------------------------
    * H5G_LINK
    *-------------------------------------------------------------------------
    */
    case H5G_LINK:
        {
            char *buf1 = NULL;
            char *buf2 = NULL;
            
            if (H5Gget_objinfo (file1_id, path1, FALSE, &sb1) < 0)
                goto out;
            if (H5Gget_objinfo (file1_id, path1, FALSE, &sb2) < 0)
                goto out;
            
            buf1 = HDmalloc (sb1.linklen);
            buf2 = HDmalloc (sb2.linklen);
            
            if (H5Gget_linkval (file1_id, path1, sb1.linklen, buf1) < 0)
                goto out;
            if (H5Gget_linkval (file2_id, path2, sb1.linklen, buf2) < 0)
                goto out;
            
            ret = HDstrcmp (buf1, buf2);
            
            /* if "buf1" != "buf2" then the links are "different" */
            nfound = (ret != 0) ? 1 : 0;
            
            if (print_objname (options, nfound))
                do_print_objname ("link", path1, path2);

            /* always print the number of differences found in verbose mode */
            if (options->m_verbose)
                print_found(nfound);
            
            HDfree (buf1);
            HDfree (buf2);
        }
        break;
        
   /*-------------------------------------------------------------------------
    * H5G_UDLINK
    *-------------------------------------------------------------------------
    */
    case H5G_UDLINK:
        {
            char *buf1 = NULL;
            char *buf2 = NULL;
            H5L_info_t li1;
            H5L_info_t li2;
            
            if(H5Lget_info(file1_id, path1, &li1, H5P_DEFAULT) < 0)
                goto out;
            if(H5Lget_info(file1_id, path1, &li2, H5P_DEFAULT) < 0)
                goto out;
            
            /* Only external links will have a query function registered */
            if(li1.type == H5L_TYPE_EXTERNAL && li2.type == H5L_TYPE_EXTERNAL)
            {
                buf1 = HDmalloc (li1.u.val_size);
                buf2 = HDmalloc (li2.u.val_size);
                
                if(H5Lget_val(file1_id, path1, buf1, li1.u.val_size, H5P_DEFAULT) < 0)
                {
                    HDfree (buf1); HDfree (buf2);
                    goto out;
                }
                if(H5Lget_val(file2_id, path2, buf2, li2.u.val_size, H5P_DEFAULT) < 0)
                {
                    HDfree (buf1); HDfree (buf2);
                    goto out;
                }
                
                /* If the buffers are the same size, compare them */
                if(li1.u.val_size == li2.u.val_size)
                {
                    if(H5Lget_val(file1_id, path1, buf1, li1.u.val_size, H5P_DEFAULT) < 0)
                    {
                        HDfree (buf1); HDfree (buf2);
                        goto out;
                    }
                    if(H5Lget_val(file2_id, path2, buf2, li2.u.val_size, H5P_DEFAULT) < 0)
                    {
                        HDfree (buf1); HDfree (buf2);
                        goto out;
                    }
                    ret = HDmemcmp (buf1, buf2, li1.u.val_size);
                }
                else
                    ret = 1;
                
                /* if "buf1" != "buf2" then the links are "different" */
                nfound = (ret != 0) ? 1 : 0;
                
                if (print_objname (options, nfound))
                    do_print_objname ("external link", path1, path2);
            }
            else
            {
            /* If one or both of these links isn't an external link, we can only
             * compare information from H5Lget_info since we don't have a query
             * function registered for them. 
             *
             * If the link classes or the buffer length are not the
             * same, the links are "different"
             */
                if((li1.type != li2.type) || (li1.u.val_size != li2.u.val_size))
                    nfound = 1;
                else
                    nfound = 0;
                
                if (print_objname (options, nfound))
                    do_print_objname ("user defined link", path1, path2);
            }
            
            /* always print the number of differences found in verbose mode */
            if (options->m_verbose)
                print_found(nfound);
            
            HDfree (buf1);
            HDfree (buf2);
        }
        break;
        
    default:
        if (options->m_verbose) 
        {
            printf("Comparison not supported: <%s> and <%s> are of type %s\n",
                path1, path2, get_type(type) );
        }
        options->not_cmp=1;
        break;
 }
 
 
 return nfound;
 
out:

 options->err_stat=1;
 
 /* close */
 /* disable error reporting */
 H5E_BEGIN_TRY
 {
     H5Tclose (type1_id);
     H5Tclose (type2_id);
     H5Gclose (grp1_id);
     H5Tclose (grp2_id);
     /* enable error reporting */
 }
 H5E_END_TRY;
 
 return nfound;
}