path: root/tools/lib/h5diff.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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)
{
    trav_info_t  *info1=NULL;
    trav_info_t  *info2=NULL;
    hid_t        file1_id = (-1);
    hid_t        file2_id = (-1);
    char         filenames[2][1024];
    hsize_t      nfound = 0;

    HDmemset(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;
    } /* end if */

    /*-------------------------------------------------------------------------
    * 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;
        } /* end if */
        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;
        } /* end if */
    /* enable error reporting */
    } H5E_END_TRY;

    /*-------------------------------------------------------------------------
    * Initialize the info structs
    *-------------------------------------------------------------------------
    */
    trav_info_init(&info1);
    trav_info_init(&info2);

    /*-------------------------------------------------------------------------
    * get the list of objects in the files
    *-------------------------------------------------------------------------
    */
    if(h5trav_getinfo(file1_id, info1) < 0 || h5trav_getinfo(file2_id, info2) < 0) {
        printf("Error: Could not 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;
    } /* end if */

   /*-------------------------------------------------------------------------
    * 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,
                              info1,
                              file2_id,
                              fname2,
                              objname2,
                              info2,
                              options);
    } /* end if */

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

    else
    {
#ifdef H5_HAVE_PARALLEL
        if(g_Parallel)
        {
            int i;

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

            HDstrcpy(filenames[0], fname1);
            HDstrcpy(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);
        } /* end if */
#endif

        nfound = diff_match(file1_id,
                            info1,
                            file2_id,
                            info2,
                            options);
    } /* end else */

    trav_info_free(info1);
    trav_info_free(info2);

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
 *
 * Aug 2008 Pedro Vicente, pvn@hdfgroup.org
 *    Added a "contents" mode check.
 *    If this mode is present, objects in both files must match (must be exactly the same)
 *    If this does not happen, the tool returns an error code of 1
 *    (instead of the success code of 0)
 *
 *-------------------------------------------------------------------------
 */
hsize_t diff_match(hid_t file1_id,
                   trav_info_t *info1,
                   hid_t file2_id,
                   trav_info_t *info2,
                   diff_opt_t *options)
{
    trav_table_t *table = NULL;
    size_t       curr1;
    size_t       curr2;
    unsigned     infile[2];
    hsize_t      nfound = 0;
    unsigned     i;

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

    curr1 = 0;
    curr2 = 0;
    while(curr1 < info1->nused && curr2 < info2->nused)
    {
        /* criteria is string compare */
        int cmp = HDstrcmp(info1->paths[curr1].path, info2->paths[curr2].path);

        if(cmp == 0) {
            infile[0] = 1;
            infile[1] = 1;
            trav_table_addflags(infile, info1->paths[curr1].path, info1->paths[curr1].type, table);

            curr1++;
            curr2++;
        } /* end if */
        else if(cmp < 0)
        {
            infile[0] = 1;
            infile[1] = 0;
            trav_table_addflags(infile, info1->paths[curr1].path, info1->paths[curr1].type, table);
            curr1++;
        } /* end else-if */
        else
        {
            infile[0] = 0;
            infile[1] = 1;
            trav_table_addflags(infile, info2->paths[curr2].path, info2->paths[curr2].type, table);
            curr2++;
        } /* end else */
    } /* end while */

    /* list1 did not end */
    infile[0] = 1;
    infile[1] = 0;
    while(curr1 < info1->nused)
    {
        trav_table_addflags(infile, info1->paths[curr1].path, info1->paths[curr1].type, table);
        curr1++;
    } /* end while */

    /* list2 did not end */
    infile[0] = 0;
    infile[1] = 1;
    while(curr2 < info2->nused)
    {
        trav_table_addflags(infile, info2->paths[curr2].path, info2->paths[curr2].type, table);
        curr2++;
    } /* end while */

   /*-------------------------------------------------------------------------
    * print the list
    *-------------------------------------------------------------------------
    */
    if(options->m_verbose)
    {
        printf("\n");
        printf("file1     file2\n");
        printf("---------------------------------------\n");
        for(i = 0; i < table->nobjs; i++) {
            char c1, c2;

            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);
        } /* end for */
        printf ("\n");
    } /* end if */



    /*-------------------------------------------------------------------------
    * regarding the return value of h5diff (0, no difference in files, 1 difference )
    * 1) the number of objects in file1 must be the same as in file2
    * 2) the graph must match, i.e same names (absolute path)
    * 3) objects with the same name must be of the same type
    *-------------------------------------------------------------------------
    */     
       
    /* number of different objects */
    if ( info1->nused != info2->nused )
    {
        options->contents = 0;
    }
    
    /* objects in one file and not the other */
    for( i = 0; i < table->nobjs; i++)
    {
        if( table->objs[i].flags[0] != table->objs[i].flags[1] )
        {
            options->contents = 0;
        }
    }

    /* objects with the same name but different HDF5 types */
    for( i = 0; i < table->nobjs; i++) 
    {
        if ( table->objs[i].flags[0] && table->objs[i].flags[1] )
        {
            if ( table->objs[i].type != table->objs[i].type )
            {
                options->contents = 0;
            }
        }
    }



    /*-------------------------------------------------------------------------
    * do the diff for common objects
    *-------------------------------------------------------------------------
    */
#ifdef H5_HAVE_PARALLEL
{
    char *workerTasks = HDmalloc((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 */
    HDmemset(workerTasks, 1, (g_nTasks - 1));
#endif

    for(i = 0; i < table->nobjs; i++)
    {
        if( table->objs[i].flags[0] && table->objs[i].flags[1])
        {
            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);
            } /* end if */
#ifdef H5_HAVE_PARALLEL
            else
            {
                int workerFound = 0;

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

                HDstrcpy(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--;
                    } /* end if */

                    /* 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;
                        } /* end if */
                    } /* end if */

                    /* 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;
                        } /* end if */
                    } /* end if */
                } /* end if */

                /* 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(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;
                    } /* end if */
                } /* end for */

                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(args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
                            } /* end if */
                        } /* end while */
                    } /* end if */
                    /* 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(args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
                        } /* end if */
                        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(args), MPI_BYTE, Status.MPI_SOURCE, MPI_TAG_ARGS, MPI_COMM_WORLD);
                        } /* end else-if */
                        else
                        {
                            printf("ERROR: Invalid tag (%d) received \n", Status.MPI_TAG);
                            MPI_Abort(MPI_COMM_WORLD, 0);
                            MPI_Finalize();
                        } /* end else */
                    } /* end else */
                } /* end if */
            } /* end else */
#endif /* H5_HAVE_PARALLEL */
        } /* end if */
    } /* end for */
    h5diffdebug("done with for loop\n");

#ifdef H5_HAVE_PARALLEL
    if(g_Parallel)
    {
        /* make sure all tasks are done */
        while(busyTasks > 0)
        {
            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--;
            } /* end if */
            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;
            } /* end else-if */
            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--;
                } /* end if */
                /* someone else must have it...wait for them to return it, then give it to the task that just asked for it. */
                else
                {
                    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);
                } /* end else */
            } /* end else-if */
            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;
            } /* end else-if */
            else if(Status.MPI_TAG == MPI_TAG_PRINT_DATA)
            {
                char  data[PRINT_DATA_MAX_SIZE + 1];
                HDmemset(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);
            } /* end else-if */
            else
            {
                printf("ph5diff-manager: ERROR!! Invalid tag (%d) received \n", Status.MPI_TAG);
                MPI_Abort(MPI_COMM_WORLD, 0);
            } /* end else */
        } /* end while */

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

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

    /* free table */
    trav_table_free(table);

    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,
                     trav_info_t *info1,
                     hid_t file2_id,
                     const char *file2_name,
                     const char *obj2_name,
                     trav_info_t *info2,
                     diff_opt_t *options)
{
    int     f1 = 0;
    int     f2 = 0;
    hsize_t nfound = 0;

    ssize_t i = h5trav_getindex (info1, obj1_name);
    ssize_t j = h5trav_getindex (info2, obj2_name);

    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->paths[i].path;
    obj2_name = info2->paths[j].path;

    /* objects are not the same type */
    if (info1->paths[i].type != info2->paths[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->paths[i].type), obj2_name,
            get_type(info2->paths[j].type));
        options->not_cmp=1;
        return 0;
    }

    nfound = diff(file1_id,
                  obj1_name,
                  file2_id,
                  obj2_name,
                  options,
                  info1->paths[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,
              h5trav_type_t type)
{
    hid_t   type1_id = (-1);
    hid_t   type2_id = (-1);
    hid_t   grp1_id = (-1);
    hid_t   grp2_id = (-1);
    int     ret;
    hsize_t nfound = 0;

    switch(type)
    {
       /*-------------------------------------------------------------------------
        * H5TRAV_TYPE_DATASET
        *-------------------------------------------------------------------------
        */
        case H5TRAV_TYPE_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);
            } /* end if */
           /*-------------------------------------------------------------------------
            * non verbose, check first if we have differences by enabling quiet mode
            * so that printing is off, and compare again if differences found,
            * disabling quiet 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);
                    } /* end if */
                }  /* end if */
                /* in quiet mode, just count differences */
                else
                    nfound = diff_dataset(file1_id, file2_id, path1, path2, options);
            } /* end else */
            break;

       /*-------------------------------------------------------------------------
        * H5TRAV_TYPE_NAMED_DATATYPE
        *-------------------------------------------------------------------------
        */
        case H5TRAV_TYPE_NAMED_DATATYPE:
            if((type1_id = H5Topen2(file1_id, path1, H5P_DEFAULT)) < 0)
                goto out;
            if((type2_id = H5Topen2(file2_id, path2, H5P_DEFAULT)) < 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;

       /*-------------------------------------------------------------------------
        * H5TRAV_TYPE_GROUP
        *-------------------------------------------------------------------------
        */
        case H5TRAV_TYPE_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;


       /*-------------------------------------------------------------------------
        * H5TRAV_TYPE_LINK
        *-------------------------------------------------------------------------
        */
        case H5TRAV_TYPE_LINK:
            {
            H5L_info_t li1, li2;
            char *buf1, *buf2;

            if(H5Lget_info(file1_id, path1, &li1, H5P_DEFAULT) < 0)
                goto out;
            if(H5Lget_info(file1_id, path1, &li2, H5P_DEFAULT) < 0)
                goto out;

            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)
                goto out;
            if(H5Lget_val(file2_id, path2, buf2, li2.u.val_size, H5P_DEFAULT) < 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;

       /*-------------------------------------------------------------------------
        * H5TRAV_TYPE_UDLINK
        *-------------------------------------------------------------------------
        */
        case H5TRAV_TYPE_UDLINK:
            {
            H5L_info_t li1, 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) {
                char *buf1, *buf2;

                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;
                } /* end if */
                if(H5Lget_val(file2_id, path2, buf2, li2.u.val_size, H5P_DEFAULT) < 0) {
                    HDfree(buf1);
                    HDfree(buf2);
                    goto out;
                } /* end if */

                /* 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;
                    } /* end if */
                    if(H5Lget_val(file2_id, path2, buf2, li2.u.val_size, H5P_DEFAULT) < 0) {
                        HDfree(buf1);
                        HDfree(buf2);
                        goto out;
                    } /* end if */
                    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);

                HDfree(buf1);
                HDfree(buf2);
            } /* end if */
            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);
            } /* end else */

            /* always print the number of differences found in verbose mode */
            if(options->m_verbose)
                print_found(nfound);
            }
            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;
}