devinfo
, devinfo_init
,
devinfo_free
,
devinfo_handle_to_device
,
devinfo_handle_to_resource
,
devinfo_handle_to_rman
,
devinfo_foreach_device_child
,
devinfo_foreach_device_resource
,
devinfo_foreach_rman_resource
,
devinfo_foreach_rman
—
device and resource information utility library
Device and Resource Information Utility Library (libdevinfo,
-ldevinfo)
#include <devinfo.h>
int
devinfo_init
(void);
void
devinfo_free
(void);
struct devinfo_dev *
devinfo_handle_to_device
(devinfo_handle_t
handle);
struct devinfo_res *
devinfo_handle_to_resource
(devinfo_handle_t
handle);
struct devinfo_rman *
devinfo_handle_to_rman
(devinfo_handle_t
handle);
int
devinfo_foreach_device_child
(struct
devinfo_dev *parent, int (*fn)(struct devinfo_dev
*child, void *arg), void *arg);
int
devinfo_foreach_device_resource
(struct
devinfo_dev *dev, int (*fn)(struct devinfo_dev *dev,
struct devinfo_res *res, void *arg), void
*arg);
int
devinfo_foreach_rman_resource
(struct
devinfo_rman *rman, int (*fn)(struct devinfo_res *res,
void *arg), void *arg);
int
devinfo_foreach_rman
(int (*fn)(struct
devinfo_rman *rman, void *arg), void *arg);
The devinfo
library provides access to the kernel's
internal device hierarchy and to the I/O resource manager. The library uses a
sysctl(3)
interface to obtain a snapshot of the kernel's state, which is then made
available to the application.
Due to the fact that the information may be logically arranged in
a number of different fashions, the library does not attempt to impose any
structure on the data.
Device, resource, and resource manager information is returned in
data structures defined in
<devinfo.h>
:
struct devinfo_dev {
devinfo_handle_t dd_handle; /* device handle */
devinfo_handle_t dd_parent; /* parent handle */
char *dd_name; /* name of device */
char *dd_desc; /* device description */
char *dd_drivername; /* name of attached driver */
char *dd_pnpinfo; /* pnp info from parent bus */
char *dd_location; /* Where bus thinks dev at */
uint32_t dd_devflags; /* API flags */
uint16_t dd_flags; /* internal dev flags */
device_state_t dd_state; /* attachment state of dev */
};
struct devinfo_rman {
devinfo_handle_t dm_handle; /* resource manager handle */
rman_res_t dm_start; /* resource start */
rman_res_t dm_size; /* resource size */
char *dm_desc; /* resource description */
};
struct devinfo_res {
devinfo_handle_t dr_handle; /* resource handle */
devinfo_handle_t dr_rman; /* resource manager handle */
devinfo_handle_t dr_device; /* owning device */
rman_res_t dr_start; /* region start */
rman_res_t dr_size; /* region size */
};
The devinfo_handle_t values can be used to
look up the correspondingly referenced structures.
devinfo_init
() takes a snapshot of the
kernel's internal device and resource state. It returns nonzero if after a
number of retries a consistent snapshot cannot be obtained.
devinfo_init
() must be called before any other
functions can be used.
devinfo_free
() releases the memory
associated with the snapshot. Any pointers returned by other functions are
invalidated by this, and devinfo_init
() must be
called again before using any other functions.
devinfo_handle_to_device
(),
devinfo_handle_to_resource
() and
devinfo_handle_to_rman
() return pointers to
devinfo_dev, devinfo_res and
devinfo_rman structures respectively based on the
devinfo_handle_t passed to them. These functions can
be used to traverse the tree from any node to any other node. If
devinfo_handle_to_device
() is passed the constant
DEVINFO_ROOT_DEVICE
it will return the handle to the
root of the device tree.
devinfo_foreach_device_child
() invokes its
callback argument fn on every device which is an
immediate child of device. The
fn function is also passed arg,
allowing state to be passed to the callback function. If
fn returns a nonzero error value the traversal is
halted, and devinfo_foreach_device_child
() returns
the error value to its caller.
devinfo_foreach_device_resource
() invokes
its callback argument fn on every resource which is
owned by device. The fn function
is also passed device and arg,
allowing state to be passed to the callback function. If
fn returns a nonzero error value the traversal is
halted, and devinfo_foreach_device_resource
()
returns the error value to its caller.
devinfo_foreach_rman_resource
() invokes
its callback argument fn on every resource within the
resource manager rman. The fn
function is also passed arg, allowing state to be
passed to the callback function. If fn returns a
nonzero error value the traversal is halted, and
devinfo_foreach_rman_resource
() returns the error
value to its caller.
devinfo_foreach_rman
() invokes its
callback argument fn on every resource manager. The
fn function is also passed arg,
allowing state to be passed to the callback function. If
fn returns a nonzero error value the traversal is
halted, and devinfo_foreach_rman
() returns the error
value to its caller.
The devinfo
library first appeared in
FreeBSD 5.0.
This is the first implementation of the library, and the interface is still
subject to refinement.
The interface does not report device classes or drivers, making it
hard to sort by class or driver.