Add tests for H5R get name APIs (#4657)

Added functionality tests for the following APIs:
H5Rget_file_name
H5Rget_obj_name
H5Rget_attr_name

Also removed "+1" when returning a name length in H5R__get_attr_name().
The exter "+1" gave an incorrect value for the length of the referenced
object's attribute name.

Fixed GH-4447

* Fix Fortran test

The C API H5Rget_attr_name incorrectly added 1 to the length of the
referenced object's attribute name, so the Fortran API h5rget_attr_name_f
removed 1 from the returned value to accommodate the incorrectness.
This PR fixes H5Rget_attr_name so this workaround in h5rget_attr_name_f
is no longer needed.

* Add test H5Aget_name against H5Rget_attr_name

fortran/src/H5Rff.F90

@@ -1180,8 +1180,6 @@ END FUNCTION H5Rget_attr_name
        c_name(1:1)(1:1) = C_NULL_CHAR
        name_len = H5Rget_attr_name(ref_ptr, c_name, 1_SIZE_T)
        IF(name_len.LT.0_SIZE_T) hdferr = H5I_INVALID_HID_F
-       ! Don't include the NULL term in the size
-       name_len = name_len - 1
     ELSE
        l = INT(LEN(name)+1,SIZE_T)
        IF(H5Rget_attr_name(ref_ptr, c_name, l) .LT. 0_SIZE_T)THEN

release_docs/RELEASE.txt

@@ -823,6 +823,15 @@ Bug Fixes since HDF5-1.14.0 release
 ===================================
     Library
     -------
+    - Fixed H5Rget_attr_name to return the length of the attribute's name
+      without the null terminator
+
+      H5Rget_file_name and H5Rget_obj_name both return the name's length
+      without the null terminator.  H5Rget_attr_name now behaves consistently
+      with the other two APIs.  Going forward, all the get character string
+      APIs in HDF5 will be modified/written in this manner, regarding the
+      length of a character string.
+
     - Fixed library to allow usage of page buffering feature for serial file
       access with parallel builds of HDF5
 

src/H5Rint.c

@@ -837,7 +837,7 @@ H5R__get_attr_name(const H5R_ref_priv_t *ref, char *buf, size_t size)
         buf[copy_len] = '\0';
     }
 
-    ret_value = (ssize_t)(attr_name_len + 1);
+    ret_value = (ssize_t)(attr_name_len);
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5R__get_attr_name() */

src/H5Rpublic.h

@@ -589,7 +589,7 @@ H5_DLL ssize_t H5Rget_obj_name(H5R_ref_t *ref_ptr, hid_t rapl_id, char *name, si
  * \details H5Rget_attr_name() retrieves the attribute name for the
  *          attribute reference pointed to by \p ref_ptr.
  *
- *          \details_namelen_plusone{attribute,H5Rget_attr_name}
+ *          \details_namelen{attribute,H5Rget_attr_name}
  *
  * \since 1.12.0
  *