/*@
MPI_Comm_get_attr - Retrieves attribute value by key
Input Parameters:
+ comm - communicator to which attribute is attached (handle)
- keyval - key value (integer)
Output Parameters:
+ attr_value - attribute value, unless 'flag' = false
- flag - true if an attribute value was extracted; false if no attribute is
associated with the key
Notes:
Attributes must be extracted from the same language as they were inserted
in with 'MPI_Comm_set_attr'. The notes for C and Fortran below explain
why.
Notes for C:
Even though the 'attr_value' arguement is declared as 'void *', it is
really the address of a void pointer. See the rationale in the
standard for more details.
.N ThreadSafe
.N Fortran
.N Errors
.N MPI_SUCCESS
.N MPI_ERR_COMM
.N MPI_ERR_KEYVAL
@*/
int MPI_Comm_get_attr(MPI_Comm comm, int comm_keyval, void *attribute_val,
int *flag)
{
int mpi_errno = MPI_SUCCESS;
MPID_MPI_STATE_DECL(MPID_STATE_MPI_COMM_GET_ATTR);
MPIR_ERRTEST_INITIALIZED_ORDIE();
MPIU_THREAD_CS_ENTER(ALLFUNC,);
MPID_MPI_FUNC_ENTER(MPID_STATE_MPI_COMM_GET_ATTR);
/* Instead, ask for a desired type. */
mpi_errno = MPIR_CommGetAttr( comm, comm_keyval, attribute_val, flag,
MPIR_ATTR_PTR );
if (mpi_errno) goto fn_fail;
/* printf( "attr value = %x\n", *(void**)attribute_val ); */
/* ... end of body of routine ... */
fn_exit:
MPID_MPI_FUNC_EXIT(MPID_STATE_MPI_COMM_GET_ATTR);
MPIU_THREAD_CS_EXIT(ALLFUNC,);
return mpi_errno;
fn_fail:
/* --BEGIN ERROR HANDLING-- */
# ifdef HAVE_ERROR_CHECKING
{
mpi_errno = MPIR_Err_create_code(
mpi_errno, MPIR_ERR_RECOVERABLE, FCNAME, __LINE__, MPI_ERR_OTHER, "**mpi_comm_get_attr",
"**mpi_comm_get_attr %C %d %p %p", comm, comm_keyval, attribute_val, flag);
}
# endif
goto fn_exit;
/* --END ERROR HANDLING-- */
}
/* This function is called by the fortran bindings. */
int MPIR_CommGetAttr_fort(MPI_Comm comm, int comm_keyval, void *attribute_val,
int *flag, MPIR_AttrType outAttrType )
{
int mpi_errno;
MPIU_THREAD_CS_ENTER(ALLFUNC,);
mpi_errno = MPIR_CommGetAttr(comm, comm_keyval, attribute_val, flag, outAttrType);
MPIU_THREAD_CS_EXIT(ALLFUNC,);
return mpi_errno;
}
/*
Return a poiner to the topology structure on a communicator.
Returns null if no topology structure is defined
*/
MPIR_Topology *MPIR_Topology_get( MPID_Comm *comm_ptr )
{
int mpi_errno = MPI_SUCCESS;
MPIR_Topology *topo_ptr;
int flag;
if (MPIR_Topology_keyval == MPI_KEYVAL_INVALID) {
return 0;
}
mpi_errno = MPIR_CommGetAttr(comm_ptr->handle, MPIR_Topology_keyval,
&topo_ptr, &flag, MPIR_ATTR_PTR );
if (mpi_errno) return NULL;
if (flag)
return topo_ptr;
return NULL;
}
/*@
MPI_Attr_get - Retrieves attribute value by key
Input Parameters:
+ comm - communicator to which attribute is attached (handle)
- keyval - key value (integer)
Output Parameters:
+ attribute_val - attribute value, unless 'flag' = false
- flag - true if an attribute value was extracted; false if no attribute is
associated with the key
Notes:
Attributes must be extracted from the same language as they were inserted
in with 'MPI_ATTR_PUT'. The notes for C and Fortran below explain why.
Notes for C:
Even though the 'attribute_val' argument is declared as 'void *', it is
really the address of a void pointer (i.e., a 'void **'). Using
a 'void *', however, is more in keeping with C idiom and allows the
pointer to be passed without additional casts.
.N ThreadSafe
.N Deprecated
The replacement for this routine is 'MPI_Comm_get_attr'.
.N Fortran
The 'attribute_val' in Fortran is a pointer to a Fortran integer, not
a pointer to a 'void *'.
.N Errors
.N MPI_SUCCESS
.N MPI_ERR_COMM
.N MPI_ERR_KEYVAL
.seealso MPI_Attr_put, MPI_Keyval_create, MPI_Attr_delete, MPI_Comm_get_attr
@*/
int MPI_Attr_get(MPI_Comm comm, int keyval, void *attribute_val, int *flag)
{
static const char FCNAME[] = "MPI_Attr_get";
int mpi_errno = MPI_SUCCESS;
MPID_Comm *comm_ptr = NULL;
MPID_MPI_STATE_DECL(MPID_STATE_MPI_ATTR_GET);
MPIR_ERRTEST_INITIALIZED_ORDIE();
MPIU_THREAD_CS_ENTER(ALLFUNC,);
MPID_MPI_FUNC_ENTER(MPID_STATE_MPI_ATTR_GET);
/* Validate parameters, especially handles needing to be converted */
# ifdef HAVE_ERROR_CHECKING
{
MPID_BEGIN_ERROR_CHECKS;
{
MPIR_ERRTEST_COMM(comm, mpi_errno);
# ifdef NEEDS_POINTER_ALIGNMENT_ADJUST
/* A common user error is to pass the address of a 4-byte
int when the address of a pointer (or an address-sized int)
should have been used. We can test for this specific
case. Note that this code assumes sizeof(MPIR_Pint) is
a power of 2. */
MPIU_ERR_CHKANDJUMP((MPIR_Pint)attribute_val & (sizeof(MPIR_Pint)-1),
mpi_errno,MPI_ERR_ARG,"**attrnotptr");
# endif
}
MPID_END_ERROR_CHECKS;
}
# endif
/* Convert MPI object handles to object pointers */
MPID_Comm_get_ptr( comm, comm_ptr );
/* Validate parameters and objects (post conversion) */
# ifdef HAVE_ERROR_CHECKING
{
MPID_BEGIN_ERROR_CHECKS;
{
/* Validate comm_ptr */
MPID_Comm_valid_ptr( comm_ptr, mpi_errno );
/* If comm_ptr is not valid, it will be reset to null */
MPIR_ERRTEST_ARGNULL(attribute_val, "attribute_val", mpi_errno);
MPIR_ERRTEST_ARGNULL(flag, "flag", mpi_errno);
}
MPID_END_ERROR_CHECKS;
}
# endif /* HAVE_ERROR_CHECKING */
/* ... body of routine ... */
mpi_errno = MPIR_CommGetAttr( comm, keyval, attribute_val, flag, MPIR_ATTR_PTR);
if (mpi_errno != MPI_SUCCESS) goto fn_fail;
/* ... end of body of routine ... */
fn_exit:
MPID_MPI_FUNC_EXIT(MPID_STATE_MPI_ATTR_GET);
MPIU_THREAD_CS_EXIT(ALLFUNC,);
return mpi_errno;
fn_fail:
/* --BEGIN ERROR HANDLING-- */
# ifdef HAVE_ERROR_CHECKING
{
mpi_errno = MPIR_Err_create_code(
mpi_errno, MPIR_ERR_RECOVERABLE, FCNAME, __LINE__, MPI_ERR_OTHER, "**mpi_attr_get",
"**mpi_attr_get %C %d %p %p", comm, keyval, attribute_val, flag);
}
# endif
mpi_errno = MPIR_Err_return_comm( comm_ptr, FCNAME, mpi_errno );
goto fn_exit;
/* --END ERROR HANDLING-- */
}
