Merge branch 'dimscale_attachement_optional' of https://github.com/gsjaardema/netcdf-c into gh2161.wif

Author: WardF

include/nc4internal.h

@@ -300,7 +300,8 @@ typedef struct NC_FILE_INFO
     nc_bool_t parallel;   /**< True if file is open for parallel access */
     nc_bool_t redef;      /**< True if redefining an existing file */
     nc_bool_t no_attr_create_order; /**< True if the creation order tracking of attributes is disabled (netcdf-4 only) */
-    int fill_mode;        /**< Fill mode for vars */
+    nc_bool_t no_dimscale_attach; /**< True if attaching dimscales to variables is disabled (netcdf-4 only) */
+    int fill_mode;        /**< Fill mode for vars - Unused internally currently */
     nc_bool_t no_write;   /**< true if nc_open has mode NC_NOWRITE. */
     NC_GRP_INFO_T *root_grp; /**< Pointer to root group. */
     short next_nc_grpid;  /**< Next available group ID. */

include/netcdf.h

@@ -164,6 +164,7 @@ Use this in mode flags for both nc_create() and nc_open(). */
 
 /* Upper 16 bits */
 #define NC_NOATTCREORD  0x20000 /**< Disable the netcdf-4 (hdf5) attribute creation order tracking */
+#define NC_NODIMSCALE_ATTACH 0x40000 /**< Disable the netcdf-4 (hdf5) attaching of dimscales to variables (#2128) */
 
 #define NC_MAX_MAGIC_NUMBER_LEN 8 /**< Max len of user-defined format magic number. */
 

libhdf5/hdf5create.c

@@ -208,6 +208,11 @@ nc4_create_file(const char *path, int cmode, size_t initialsz,
         BAIL(NC_EHDFERR);
 #endif
 
+    if (cmode & NC_NODIMSCALE_ATTACH) {
+      /* See https://github.com/Unidata/netcdf-c/issues/2128 */
+      nc4_info->no_dimscale_attach = NC_TRUE;
+    }
+
     if(nc4_info->mem.inmemory) {
         retval = NC4_create_image_file(nc4_info,initialsz);
         if(retval)
@@ -337,7 +342,7 @@ nc4_H5Fcreate(const char *filename0, unsigned flags, hid_t fcpl_id, hid_t fapl_i
 
 #ifdef HDF5_UTF8_PATHS
     NCpath2utf8(filename0,&filename);
-#else    
+#else
     filename = strdup(filename0);
 #endif
     /* Canonicalize it since we are not opening the file ourselves */

libhdf5/nc4hdf.c

@@ -1957,9 +1957,11 @@ nc4_rec_write_metadata(NC_GRP_INFO_T *grp, nc_bool_t bad_coord_order)
         }
     } /* end while */
 
-    /* Attach dimscales to vars in this group. */
-    if ((retval = attach_dimscales(grp)))
-        return retval;
+    /* Attach dimscales to vars in this group. Unless directed not to. */
+    if (!grp->nc4_info->no_dimscale_attach) {
+        if ((retval = attach_dimscales(grp)))
+            return retval;
+    }
 
     /* If there are any child groups, write their metadata. */
     for (i = 0; i < ncindexsize(grp->children); i++)