path: root/tools/lib/h5diff.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
 * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#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: print object name 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;
}

#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;
 int 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
 *  H5G_UDLINK   Object is a user-defined 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_t 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))
    parallel_print("Dataset:     <%s> and <%s>\n", path1, path2);
   nfound = diff_dataset (file1_id, file2_id, path1, path2, options);
   /* always print the number of differences found */
   print_found(nfound);
  }
 /*-------------------------------------------------------------------------
  * non verbose, check first if we have differences
  *-------------------------------------------------------------------------
  */
  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))
      parallel_print("Dataset:     <%s> and <%s>\n", path1, path2);
     nfound = diff_dataset (file1_id, file2_id, path1, path2, options);
     /* print the number of differences found only when found
     this is valid for the default mode and report mode */
     print_found(nfound);
    }  /*if nfound */
   } /*if quiet */

 /*-------------------------------------------------------------------------
  * quiet mode, just count differences
  *-------------------------------------------------------------------------
  */
   else
   {
    nfound = diff_dataset (file1_id, file2_id, path1, path2, options);
   }
  }   /*else verbose */

  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))
   parallel_print("Datatype:    <%s> and <%s>\n", 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)
   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:
  if ((grp1_id = H5Gopen (file1_id, path1)) < 0)
   goto out;
  if ((grp2_id = H5Gopen (file2_id, path2)) < 0)
   goto out;

  ret = HDstrcmp (path1, path2);

  /* if "path1" != "path2" then the groups are "different" */
  nfound = (ret != 0) ? 1 : 0;

  if (print_objname (options, nfound))
   parallel_print("Group:       <%s> and <%s>\n", 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)
   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))
    parallel_print("Soft Link:        <%s> and <%s>\n", 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.link_size);
      buf2 = HDmalloc (li2.u.link_size);

      if(H5Lget_val(file1_id, path1, buf1, li1.u.link_size, H5P_DEFAULT) < 0)
      {
        HDfree (buf1); HDfree (buf2);
        goto out;
      }
      if(H5Lget_val(file2_id, path2, buf2, li2.u.link_size, H5P_DEFAULT) < 0)
      {
        HDfree (buf1); HDfree (buf2);
        goto out;
      }

      /* If the buffers are the same size, compare them */
      if(li1.u.link_size == li2.u.link_size)
      {
        if(H5Lget_val(file1_id, path1, buf1, li1.u.link_size, H5P_DEFAULT) < 0)
        {
          HDfree (buf1); HDfree (buf2);
          goto out;
        }
        if(H5Lget_val(file2_id, path2, buf2, li2.u.link_size, H5P_DEFAULT) < 0)
        {
          HDfree (buf1); HDfree (buf2);
          goto out;
        }
        ret = HDmemcmp (buf1, buf2, li1.u.link_size);
      }
      else
        ret = 1;

      /* if "buf1" != "buf2" then the links are "different" */
      nfound = (ret != 0) ? 1 : 0;

      if (print_objname (options, nfound))
        parallel_print("External Link:        <%s> and <%s>\n", 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.link_size != li2.u.link_size))
        nfound = 1;
      else
        nfound = 0;

      if (print_objname (options, nfound))
        parallel_print("User-defined Link:        <%s> and <%s>\n", 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:
  nfound = 0;
  if (options->m_verbose)
  {
   parallel_print("Comparison not supported: <%s> and <%s> are of type %s\n",
    path1, path2, get_type (type));
   options->not_cmp=1;
  }

  break;
 } /* switch */


out:

 /* 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;
}