more testing for late fill setting

libdispatch/dvar.c

@@ -546,42 +546,57 @@ NC_getshape(int ncid, int varid, int ndims, size_t* shape)
    return status;
 }
 
-/*! Set the fill value for a variable.
+/**
-
+ * @ingroup variables
-\ingroup variables
+ *
-
+ * Set the fill value for a variable.
-\param ncid NetCDF ID, from a previous call to nc_open or
+ *
-nc_create.
+ * @note For netCDF classic, 64-bit offset, and CDF5 formats, it is
-
+ * allowed (but not good practice) to set the fill value after data
-\param varid Variable ID.
+ * have been written to the variable. In this case, unless the
-
+ * variable has been completely specified (without gaps in the data),
-\param no_fill Set to NC_NOFILL to turn off fill mode for this
+ * any existing filled values will not be recognized as fill values by
-variable. Set to NC_FILL (the default) to turn on fill mode for the
+ * applications reading the data. Best practice is to set the fill
-variable.
+ * value after the variable has been defined, but before any data have
-
+ * been written to that varibale. In NetCDF-4 files, this is enforced
-\param fill_value the fill value to be used for this variable. Must be
+ * by the HDF5 library. For netCDF-4 files, an error is returned if
-the same type as the variable. This must point to enough free memory
+ * the user attempts to set the fill value after writing data to the
-to hold one element of the data type of the variable. (For example, an
+ * variable.
-NC_INT will require 4 bytes for it's fill value, which is also an
-NC_INT.)
 
+ * @param ncid NetCDF ID, from a previous call to nc_open or
+ * nc_create.
+ * @param varid Variable ID.
+ * @param no_fill Set to NC_NOFILL to turn off fill mode for this
+ * variable. Set to NC_FILL (the default) to turn on fill mode for the
+ * variable.
+ * @param fill_value the fill value to be used for this variable. Must
+ * be the same type as the variable. This must point to enough free
+ * memory to hold one element of the data type of the variable. (For
+ * example, an NC_INT will require 4 bytes for it's fill value, which
+ * is also an NC_INT.)
+ *
  * @returns ::NC_NOERR No error.
  * @returns ::NC_EBADID Bad ID.
- * @returns ::NC_ENOTINDEFINE Not in define mode.  This is returned for
+ * @returns ::NC_ENOTINDEFINE Not in define mode.  This is returned
-netCDF classic, 64-bit offset, or 64-bit data files, or for netCDF-4 files,
+ * for netCDF classic, 64-bit offset, or 64-bit data files, or for
-when they were created with NC_STRICT_NC3 flag. See \ref nc_create.
+ * netCDF-4 files, when they were created with NC_STRICT_NC3 flag. See
+ * @ref nc_create.
  * @returns ::NC_EPERM Attempt to create object in read-only file.
-
+ * @returns ::NC_ELATEDEF (NetCDF-4 only). Returned when user attempts
-\section nc_def_var_fill_example Example
+ * to set fill value after data are written.
-
+ * @returns ::NC_EGLOBAL Attempt to set fill value on NC_GLOBAL.
-In this example from libsrc4/tst_vars.c, a variable is defined, and
+ *
-the fill mode turned off. Then nc_inq_fill() is used to check that the
+ * @section nc_def_var_fill_example Example
-setting is correct. Then some data are written to the variable. Since
+ *
-the data that are written do not cover the full extent of the
+ * In this example from libsrc4/tst_vars.c, a variable is defined, and
-variable, the missing values will just be random. If fill value mode
+ * the fill mode turned off. Then nc_inq_fill() is used to check that
-was turned on, the missing values would get the fill value.
+ * the setting is correct. Then some data are written to the
-
+ * variable. Since the data that are written do not cover the full
-\code
+ * extent of the variable, the missing values will just be random. If
+ * fill value mode was turned on, the missing values would get the
+ * fill value.
+ *
+ @code
 #define DIM7_LEN 2
 #define DIM7_NAME "dim_7_from_Indiana"
 #define VAR7_NAME "var_7_from_Idaho"
@@ -608,7 +623,8 @@ was turned on, the missing values would get the fill value.
       if (nc_get_var1_ushort(ncid, varid, index, &ushort_data_in)) ERR;
 
       if (nc_close(ncid)) ERR;
-\endcode
+ @endcode
+ * @author Glenn Davis, Ed Hartnett, Dennis Heimbigner
 */
 int
 nc_def_var_fill(int ncid, int varid, int no_fill, const void *fill_value)
@@ -617,7 +633,7 @@ nc_def_var_fill(int ncid, int varid, int no_fill, const void *fill_value)
     int stat = NC_check_id(ncid,&ncp);
     if(stat != NC_NOERR) return stat;
 
-    /* Dennis Heimbigner: (Using NC_GLOBAL is ilegal, as this API) has no
+    /* Dennis Heimbigner: Using NC_GLOBAL is illegal, as this API has no
      * provision for specifying the type of the fillvalue, it must of necessity
      * be using the type of the variable to interpret the bytes of the
      * fill_value argument.

nc_test/tst_formats.c

@@ -17,6 +17,7 @@
 #define DIM_LEN 10
 #define VAR_NAME "Copernicus_var"
 #define DIM_NAME "Copernicus_dim"
+#define NUM_FILL_WRITE_TESTS 2
 
 /* Determine how many formats are available, and what they are. */
 void
@@ -103,7 +104,7 @@ main(int argc, char **argv)
    printf("\n*** Testing netcdf format functions.\n");
    {
       int ncid;
-      int f;
+      int f, d;
       int format[MAX_NUM_FORMATS];
       int num_formats;
 
@@ -160,20 +161,51 @@ main(int argc, char **argv)
             if (nc_close(ncid)) ERR;
          }
          SUMMARIZE_ERR;
-         printf("*** testing NC_ELATEFILL errors with format %d...", format[f]);
+         for (d = 0; d < NUM_FILL_WRITE_TESTS; d++)
          {
+            printf("*** testing late fill handling with format %d writing %d...", format[f], d);
             char file_name[NC_MAX_NAME + 1];
             int dimid, varid;
+            size_t index = {DIM_LEN - 1};
+            int data = TEST_VAL_42;
+            int data_in;
+            int fill_value = TEST_VAL_42 * 2;
 
-            sprintf(file_name, "%s_%d_elatefill.nc", FILE_NAME_BASE, format[f]);
+            /* Try to set fill mode after data have been written. */
+            sprintf(file_name, "%s_%d_%d_elatefill.nc", FILE_NAME_BASE, format[f], d);
             if (nc_set_default_format(format[f], NULL)) ERR;
             if (nc_create(file_name, 0, &ncid)) ERR;
             if (nc_def_dim(ncid, DIM_NAME, DIM_LEN, &dimid)) ERR;
             if (nc_def_var(ncid, VAR_NAME, NC_INT, NDIM1, &dimid, &varid)) ERR;
             if (nc_enddef(ncid)) ERR;
+            /* For netCDF-4, we don't actually have to write data to
+             * prevent future setting of the fill value. Once the user
+             * leaves calls enddef after defining a var, fill values
+             * can no longer be set. */
+            if (d)
+               if (nc_put_var1_int(ncid, varid, &index, &data)) ERR;
+            if (nc_redef(ncid)) ERR;
+            /* Setting the fill value after data are written is
+             * allowed in classic formats, but not netcdf-4. */
+            if (format[f] == NC_FORMAT_CLASSIC || format[f] == NC_FORMAT_64BIT_OFFSET ||
+                format[f] == NC_FORMAT_CDF5)
+            {
+               if (nc_def_var_fill(ncid, varid, NC_FILL, &fill_value)) ERR;
+            }
+            else
+            {
+               if (nc_def_var_fill(ncid, varid, NC_FILL, &fill_value) != NC_ELATEDEF) ERR;
+            }
+            if (nc_enddef(ncid)) ERR;
             if (nc_close(ncid)) ERR;
-         }
+
-         SUMMARIZE_ERR;
+            /* Open the file and check data. */
+            if (nc_open(file_name, NC_NOWRITE, &ncid)) ERR;
+            if (nc_get_var1_int(ncid, varid, &index, &data_in)) ERR;
+            if (data_in != (d ? data : NC_FILL_INT)) ERR;
+            if (nc_close(ncid)) ERR;
+            SUMMARIZE_ERR;
+         } /* next fill val write test */
       } /* next format */
    }
    FINAL_RESULTS;