Using sparse matrix library files in C

I'm working on a large scale project in which I'm designing a sparse matrix vector application but I'm still working to understand the code. I'm beginning by building开发者_如何学JAVA the foundation for the application but I've run into a segmentation fault when executing the program. I've tracked the problem to this loop within the MatrixRead function and am enclosing the code below. When the program is executed I tried programming in some test messages and the program appears to execute all the loops but it returns the segmentation fault at the end. Of course, this is all just speculation. Any help would be awesome. Thanks!

    while (ret != EOF && row <= mat->rows) 
       {    
          if (row != curr_row) // Won't execute for first iteration
              {

                  /* store this row */

                 MatrixSetRow(mat, curr_row, len, ind, val);

                     /* check if the previous row is zero  */

                     i = 1;
                     while(row != curr_row + i)
                     { 
                         mat->lens[curr_row+i-1] = 0;
                         mat->inds[curr_row+i-1] = 0;
                         mat->vals[curr_row+i-1] = 0;  
                         i++;
                     }
                     curr_row = row;

                     /* reset row pointer */

                     len = 0;
               }

         ind[len] = col;
         val[len] = value;
         len++;

         ret = fscanf(file, "%lf %lf %lf", &r1, &c1, &value);

         col = (int) (c1);
         row = (int) (r1);
      }

/* Store the final row */
    if (ret == EOF || row > mat->rows)
    MatrixSetRow(mat, mat->rows, len, ind, val);

Here's the code for the MatrixSetRow function:

    /*--------------------------------------------------------------------------
     * MatrixSetRow - Set a row in a matrix.  Only local rows can be set.
     * Once a row has been set, it should not be set again, or else the 
     * memory used by the existing row will not be recovered until 
     * the matrix is destroyed.  "row" is in global coordinate numbering.
     *--------------------------------------------------------------------------*/

    void MatrixSetRow(Matrix *mat, int row, int len, int *ind, double *val)
    {
        row -= 1;

        mat->lens[row] = len;
        mat->inds[row] = (int *) MemAlloc(mat->mem, len*sizeof(int));
        mat->vals[row] = (double *) MemAlloc(mat->mem, len*sizeof(double));

        if (ind != NULL)
            memcpy(mat->inds[row], ind, len*sizeof(int));

        if (val != NULL)
            memcpy(mat->vals[row], val, len*sizeof(double));
    }

I'm also including the code for the Matrix.h file that went with it, where the members of Matrix are defined:

    #include <stdio.h>
    #include "Common.h"
    #include "Mem.h"

    #ifndef _MATRIX_H
    #define _MATRIX_H

    typedef struct
    {

        int      rows;
        int      columns;

        Mem     *mem;

        int     *lens;
        int    **inds;
        double **vals;

    }
    Matrix;