dmi_registry_resolve

Synopsis

#include <opendmi/registry.h>

bool dmi_registry_resolve(
        dmi_registry_t   *registry,
        dmi_handle_t      handle,
        const dmi_type_t *type,
        dmi_entity_t    **pentity);

bool dmi_registry_resolve_any(
        dmi_registry_t          *registry,
        dmi_handle_t             handle,
        const dmi_type_t *const *types,
        dmi_entity_t           **pentity);

bool dmi_registry_resolve_id(
        dmi_registry_t *registry,
        dmi_handle_t    handle,
        dmi_type_id_t   type_id,
        dmi_entity_t  **pentity);

Description

The functions resolve the handle a structure refers to another one by into the entity of that structure, and are meant for the link handlers of the structure types, including the ones of a module built out of the tree of the library, see dmi_entity_link.

Unlike dmi_registry_lookup, they tell a reference which is not set, which is not an error, from a broken one, which is: the reference is not set if the handle is DMI_HANDLE_INVALID (0xFFFF) or DMI_HANDLE_UNSUPPORTED (0xFFFE), and broken if there is no structure of the handle, or if the structure is of another type than the expected one. Some firmware writes the handle 0x0000 for a reference which is not set as well, while 0x0000 is a handle a structure may have, so a reference of 0x0000 to a structure of another type than the expected one is taken as not set, unless the context of the registry has DMI_CONTEXT_FLAG_STRICT.

The dmi_registry_resolve function expects a structure of the structure type type, which is the type of the specification the structure is decoded by, see dmi_entity_type, and the dmi_registry_resolve_any function a structure of any of the structure types listed by types.

The dmi_registry_resolve_id function expects a structure found at the type number type_id, whatever specification it is decoded by, for the references whose type the data gives itself, e.g. the items of a group association.

Parameters

registry: Registry to look the structure up in.
handle: Handle the reference holds.
type: Expected structure type, or DMI_TYPE_ANY to accept a structure of any type.
types: Array of the expected structure types, terminated by nullptr, or nullptr to accept a structure of any type. The array must list at least one type.
type_id: Expected type number, or DMI_TYPE_ID_INVALID to accept a structure of any type.
pentity: Variable to store the entity of the structure in. It is set to nullptr if the reference is not set or is broken.

Return value

The functions return true if the reference has been resolved or is not set, and false if it is broken, if registry or pentity is nullptr, or if types lists no type.

Errors

The errors are raised against the context of the registry.

DMI_ERROR_ARGUMENT_NULL: Raised if registry or pentity is nullptr. Without a registry it is not reported, since there is no context to hold it.
DMI_ERROR_ARGUMENT_INVALID: Raised by dmi_registry_resolve_any if types lists no type.
DMI_ERROR_ENTITY_NOT_FOUND: Raised if there is no structure of the handle.
DMI_ERROR_ENTITY_TYPE_INVALID: Raised if the structure of the handle is of another type than the expected one.

Example

static bool cooling_device_link(dmi_entity_t *entity)
{
    dmi_context_t        *context  = dmi_entity_context(entity);
    dmi_registry_t       *registry = dmi_get_registry(context);
    dmi_cooling_device_t *info     = dmi_entity_info(entity,
                                                     DMI_TYPE(cooling_device));

    return dmi_registry_resolve(registry, info->probe_handle,
                                DMI_TYPE(temperature_probe), &info->probe);
}