34.4. Directives¶

This section details the directives of the Object Services. A subsection is dedicated to each of this manager’s directives and lists the calling sequence, parameters, description, return values, and notes of the directive.

34.4.1. rtems_build_id()¶

Builds the object identifier from the API, class, MPCI node, and index components.

CALLING SEQUENCE:

rtems_id rtems_build_id(
  uint32_t api,
  uint32_t the_class,
  uint32_t node,
  uint32_t index
);

PARAMETERS:

api: This parameter is the API of the object identifier to build.
the_class: This parameter is the class of the object identifier to build.
node: This parameter is the MPCI node of the object identifier to build.
index: This parameter is the index of the object identifier to build.

RETURN VALUES:

Returns the object identifier built from the API, class, MPCI node, and index components.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.2. rtems_build_name()¶

Builds the object name composed of the four characters.

CALLING SEQUENCE:

rtems_name rtems_build_name( char c1, char c2, char c3, char c4 );

PARAMETERS:

c1: This parameter is the first character of the name.
c2: This parameter is the second character of the name.
c3: This parameter is the third character of the name.
c4: This parameter is the fourth character of the name.

DESCRIPTION:

This directive takes the four characters provided as arguments and composes a 32-bit object name with c1 in the most significant 8-bits and c4 in the least significant 8-bits.

RETURN VALUES:

Returns the object name composed of the four characters.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.3. rtems_object_get_classic_name()¶

Gets the object name associated with the object identifier.

CALLING SEQUENCE:

rtems_status_code rtems_object_get_classic_name(
  rtems_id    id,
  rtems_name *name
);

PARAMETERS:

id: This parameter is the object identifier to get the name.
name: This parameter is the pointer to an rtems_name object. When the directive call is successful, the object name associated with the object identifier will be stored in this object.

RETURN VALUES:

RTEMS_SUCCESSFUL: The requested operation was successful.
RTEMS_INVALID_ADDRESS: The name parameter was NULL.
RTEMS_INVALID_ID: There was no object information available for the object identifier.
RTEMS_INVALID_ID: The object name associated with the object identifier was a string.
RTEMS_INVALID_ID: There was no object associated with the object identifier.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.4. rtems_object_get_name()¶

Gets the object name associated with the object identifier as a string.

CALLING SEQUENCE:

char *rtems_object_get_name( rtems_id id, size_t length, char *name );

PARAMETERS:

id: This parameter is the object identifier to get the name.
length: This parameter is the buffer length in bytes.
name: This parameter is the pointer to a buffer of the specified length.

DESCRIPTION:

The object name is stored in the name buffer. If the name buffer length is greater than zero, then the stored object name will be NUL terminated. The stored object name may be truncated to fit the length. There is no indication if a truncation occurred. Every attempt is made to return name as a printable string even if the object has the Classic API 32-bit integer style name.

RETURN VALUES:

NULL: The length parameter was 0.
NULL: The name parameter was NULL.
NULL: There was no object information available for the object identifier.
NULL: There was no object associated with the object identifier.

Returns the name parameter value, if there is an object name associated with the object identifier.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.5. rtems_object_set_name()¶

Sets the object name of the object associated with the object identifier.

CALLING SEQUENCE:

rtems_status_code rtems_object_set_name( rtems_id id, const char *name );

PARAMETERS:

id: This parameter is the object identifier of the object to set the name.
name: This parameter is the object name to set.

DESCRIPTION:

This directive will set the object name based upon the user string.

RETURN VALUES:

RTEMS_SUCCESSFUL: The requested operation was successful.
RTEMS_INVALID_ADDRESS: The name parameter was NULL.
RTEMS_INVALID_ID: There was no object information available for the object identifier.
RTEMS_INVALID_ID: There was no object associated with the object identifier.
RTEMS_NO_MEMORY: There was no memory available to duplicate the name.

NOTES:

This directive can be used to set the name of objects which do not have a naming scheme per their API.

If the object specified by id is of a class that has a string name, this directive will free the existing name to the RTEMS Workspace and allocate enough memory from the RTEMS Workspace to make a copy of the string located at name.

If the object specified by id is of a class that has a 32-bit integer style name, then the first four characters in name will be used to construct the name.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within device driver initialization context.
The directive may be called from within task context.
The directive may obtain and release the object allocator mutex. This may cause the calling task to be preempted.

34.4.6. rtems_object_id_get_api()¶

Gets the API component of the object identifier.

CALLING SEQUENCE:

int rtems_object_id_get_api( rtems_id id );

PARAMETERS:

id: This parameter is the object identifier with the API component to get.

RETURN VALUES:

Returns the API component of the object identifier.

NOTES:

This directive does not validate the object identifier provided in id.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.7. rtems_object_id_get_class()¶

Gets the class component of the object identifier.

CALLING SEQUENCE:

int rtems_object_id_get_class( rtems_id id );

PARAMETERS:

id: This parameter is the object identifier with the class component to get.

RETURN VALUES:

Returns the class component of the object identifier.

NOTES:

This directive does not validate the object identifier provided in id.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.8. rtems_object_id_get_node()¶

Gets the MPCI node component of the object identifier.

CALLING SEQUENCE:

int rtems_object_id_get_node( rtems_id id );

PARAMETERS:

id: This parameter is the object identifier with the MPCI node component to get.

RETURN VALUES:

Returns the MPCI node component of the object identifier.

NOTES:

This directive does not validate the object identifier provided in id.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.9. rtems_object_id_get_index()¶

Gets the index component of the object identifier.

CALLING SEQUENCE:

int rtems_object_id_get_index( rtems_id id );

PARAMETERS:

id: This parameter is the object identifier with the index component to get.

RETURN VALUES:

Returns the index component of the object identifier.

NOTES:

This directive does not validate the object identifier provided in id.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.10. rtems_object_id_api_minimum()¶

Gets the lowest valid value for the API component of an object identifier.

CALLING SEQUENCE:

int rtems_object_id_api_minimum( void );

RETURN VALUES:

Returns the lowest valid value for the API component of an object identifier.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.11. rtems_object_id_api_maximum()¶

Gets the highest valid value for the API component of an object identifier.

CALLING SEQUENCE:

int rtems_object_id_api_maximum( void );

RETURN VALUES:

Returns the highest valid value for the API component of an object identifier.

CONSTRAINTS:

The following constraints apply to this directive:

The directive is implemented by a macro and may be called from within C/C++ constant expressions. In addition, a function implementation of the directive exists for bindings to other programming languages.
The directive will not cause the calling task to be preempted.

34.4.12. rtems_object_api_minimum_class()¶

Gets the lowest valid class value of the object API.

CALLING SEQUENCE:

int rtems_object_api_minimum_class( int api );

PARAMETERS:

api: This parameter is the object API to get the lowest valid class value.

RETURN VALUES:

-1: The object API was invalid.

Returns the lowest valid class value of the object API.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.13. rtems_object_api_maximum_class()¶

Gets the highest valid class value of the object API.

CALLING SEQUENCE:

int rtems_object_api_maximum_class( int api );

PARAMETERS:

api: This parameter is the object API to get the highest valid class value.

RETURN VALUES:

0: The object API was invalid.

Returns the highest valid class value of the object API.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.14. rtems_object_get_api_name()¶

Gets a descriptive name of the object API.

CALLING SEQUENCE:

const char *rtems_object_get_api_name( int api );

PARAMETERS:

api: This parameter is the object API to get the name.

RETURN VALUES:

“BAD API”: The API was invalid.

Returns a descriptive name of the API, if the API was valid.

NOTES:

The string returned is from constant space. Do not modify or free it.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.15. rtems_object_get_api_class_name()¶

Gets a descriptive name of the object class of the object API.

CALLING SEQUENCE:

const char *rtems_object_get_api_class_name( int the_api, int the_class );

PARAMETERS:

the_api: This parameter is the object API of the object class.
the_class: This parameter is the object class of the object API to get the name.

RETURN VALUES:

“BAD API”: The API was invalid.
“BAD CLASS”: The class of the API was invalid.

Returns a descriptive name of the class of the API, if the class of the API and the API were valid.

NOTES:

The string returned is from constant space. Do not modify or free it.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.16. rtems_object_get_class_information()¶

Gets the object class information of the object class of the object API.

CALLING SEQUENCE:

rtems_status_code rtems_object_get_class_information(
  int                                 the_api,
  int                                 the_class,
  rtems_object_api_class_information *info
);

PARAMETERS:

the_api: This parameter is the object API of the object class.
the_class: This parameter is the object class of the object API to get the class information.
info: This parameter is the pointer to an rtems_object_api_class_information object. When the directive call is successful, the object class information of the class of the API will be stored in this object.

RETURN VALUES:

RTEMS_SUCCESSFUL: The requested operation was successful.
RTEMS_INVALID_ADDRESS: The info parameter was NULL.
RTEMS_INVALID_NUMBER: The class of the API or the API was invalid.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.17. rtems_object_get_local_node()¶

Gets the local MPCI node number.

CALLING SEQUENCE:

uint16_t rtems_object_get_local_node( void );

RETURN VALUES:

Returns the local MPCI node number.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.

34.4.18. RTEMS_OBJECT_ID_INITIAL()¶

Builds the object identifier with the lowest index from the API, class, and MPCI node components.

CALLING SEQUENCE:

rtems_id RTEMS_OBJECT_ID_INITIAL(
  uint32_t api,
  uint32_t class,
  uint32_t node
);

PARAMETERS:

api: This parameter is the API of the object identifier to build.
class: This parameter is the class of the object identifier to build.
node: This parameter is the MPCI node of the object identifier to build.

RETURN VALUES:

Returns the object identifier with the lowest index built from the API, class, and MPCI node components.

CONSTRAINTS:

The following constraints apply to this directive:

The directive may be called from within any runtime context.
The directive will not cause the calling task to be preempted.