BT_DEV(3) BSD Library Functions Manual BT_DEV(3)NAME
bt_devaddr, bt_devname, bt_devenum, bt_devinfo, bt_devopen, bt_devsend,
bt_devrecv, bt_devreq, bt_devfilter, bt_devfilter_pkt_set,
bt_devfilter_pkt_clr, bt_devfilter_pkt_tst, bt_devfilter_evt_set,
bt_devfilter_evt_clr, bt_devfilter_evt_tst, bt_devinquiry — Bluetooth
device access routines
LIBRARY
library “libbluetooth”
SYNOPSIS
#include <bluetooth.h>
int
bt_devaddr(const char *name, bdaddr_t *bdaddr);
int
bt_devname(char *name, const bdaddr_t *bdaddr);
int
bt_devenum(int (*cb)(int, const struct bt_devinfo *, void *), void *arg);
int
bt_devinfo(const char *name, struct bt_devinfo *info);
int
bt_devopen(const char *name, int flags);
ssize_t
bt_devsend(int s, uint16_t opcode, void *param, size_t plen);
ssize_t
bt_devrecv(int s, void *buf, size_t size, time_t timeout);
int
bt_devreq(int s, struct bt_devreq *req, time_t timeout);
int
bt_devfilter(int s, const struct bt_devfilter *new,
struct bt_devfilter *old);
void
bt_devfilter_pkt_set(struct bt_devfilter *filter, uint8_t type);
void
bt_devfilter_pkt_clr(struct bt_devfilter *filter, uint8_t type);
int
bt_devfilter_pkt_tst(const struct bt_devfilter *filter, uint8_t type);
void
bt_devfilter_evt_set(struct bt_devfilter *filter, uint8_t event);
void
bt_devfilter_evt_clr(struct bt_devfilter *filter, uint8_t event);
int
bt_devfilter_evt_tst(const struct bt_devfilter *filter, uint8_t event);
int
bt_devinquiry(const char *name, time_t timeout, int max_rsp,
struct bt_devinquiry **iip);
DESCRIPTION
These routines are designed to provide access to locally configured Blue‐
tooth devices in an operating system independent manner via a socket pro‐
viding access to Bluetooth HCI packets.
FUNCTIONS
bt_devaddr(name, bdaddr)
Return a Bluetooth device address. bt_devaddr() will return 1 if
the NUL-terminated name string refers to a Bluetooth device present
in the system, otherwise 0. The name may be given as a device name
(eg "ubt0") or Bluetooth device address (eg "00:11:22:33:44:55")
and the actual device address will be written to bdaddr if not
NULL.
bt_devname(name, bdaddr)
Return a Bluetooth device name. bt_devname() returns 1 if the
bdaddr refers to a Bluetooth device present in the system, other‐
wise 0. The name buffer, if given, should have space for at least
HCI_DEVNAME_SIZE bytes and the string will be NUL-terminated.
bt_devenum(cb, arg)
Enumerate Bluetooth devices present in the system. For each device
found, the cb function (if not NULL) will be called with the arg
argument provided, a fully populated bt_devinfo structure and,
where the device is enabled, a socket handle as returned by
bt_devopen(). The callback function can halt the enumeration by
returning a non-zero value, and bt_devenum() returns the number of
successfully enumerated devices.
bt_devinfo(name, info)
Obtain information from a Bluetooth device present in the system.
The info argument is a pointer to a bt_devinfo structure into which
information about device name is placed. The bt_devinfo structure
contains at least the following members:
char devname[HCI_DEVNAME_SIZE];
int enabled; /* device is enabled */
/* device information */
bdaddr_t bdaddr;
uint8_t features[HCI_FEATURES_SIZE];
uint16_t acl_size; /* max ACL data size */
uint16_t acl_pkts; /* total ACL packet buffers */
uint16_t sco_size; /* max SCO data size */
uint16_t sco_pkts; /* total SCO packet buffers */
/* flow control */
uint16_t cmd_free; /* available CMD packet buffers */
uint16_t acl_free; /* available ACL packet buffers */
uint16_t sco_free; /* available ACL packet buffers */
/* statistics */
uint32_t cmd_sent;
uint32_t evnt_recv;
uint32_t acl_recv;
uint32_t acl_sent;
uint32_t sco_recv;
uint32_t sco_sent;
uint32_t bytes_recv;
uint32_t bytes_sent;
/* device settings */
uint16_t link_policy_info;
uint16_t packet_type_info;
uint16_t role_switch_info;
Because a Bluetooth device must be enabled in order to retrieve
information, the enabled flag should be tested to be non-zero
before relying on further data.
bt_devopen(name, flags)
Return a Bluetooth HCI socket handle bound and connected to the
named Bluetooth device or, if name is NULL, enabled to receive
packets from any device. The socket should be closed using
close(2) after use. Any combination of the following flags may be
used to pre-set the socket options:
BTOPT_DIRECTION Enable control messages on each packet indicating
the direction of travel.
BTOPT_TIMESTAMP Enable control messages providing packet time‐
stamps.
The default filter on the socket will only allow the HCI Event
packets "Command Status" and "Command Complete" to be received.
bt_devsend(s, opcode, param, plen)
Send an HCI command packet on the socket s. The opcode should be
in host byte order and the param and plen arguments can be used to
provide command parameter data. bt_devsend() will return the num‐
ber of bytes successfully written.
bt_devrecv(s, buf, size, timeout)
Receive a single HCI packet on the socket s. bt_devrecv() will
return the number of bytes successfully received unless the pro‐
vided buffer could not contain the entire packet, or if a timeout
was requested with a non-negative timeout value.
bt_devreq(s, req, timeout)
Make an HCI request on the socket s. The req argument is a pointer
to a bt_devreq structure, defined as:
struct bt_devreq {
uint16_t opcode;
uint8_t event;
void *cparam;
size_t clen;
void *rparam;
size_t rlen;
};
bt_devreq() sends an HCI command packet with the given opcode and
command parameters of clen bytes at cparam then waits up to timeout
seconds for the command to return a "Command Complete" event. In
the case where the command returns "Command Status" and an addi‐
tional event, and where the status indicates that the command is in
progress, bt_devreq() will wait for the additional event specified
in the request. If required, any response will be copied into the
buffer of rlen bytes at rparam, and rlen will be adjusted to indi‐
cate the number of bytes stored. bt_devreq() temporarily modifies
the socket filter.
bt_devfilter(s, new, old)
Update or extract the packet filter on HCI socket s. Filters can
be set to indicate packet types (Commands, Events, ACL and SCO
data), and individual event IDs. Where old is given, the currently
set filter will be extracted first, then if new is given, the fil‐
ter will be updated.
bt_devfilter_pkt_set(filter, type)
Set packet type in filter.
bt_devfilter_pkt_clr(filter, type)
Clear packet type from filter.
bt_devfilter_pkt_tst(filter, type)
Test if filter has packet type set.
bt_devfilter_evt_set(filter, event)
Set event ID in filter.
bt_devfilter_evt_clr(filter, event)
Clear event ID from filter.
bt_devfilter_evt_tst(filter, event)
Test if filter has event ID set.
bt_devinquiry(name, timeout, max_rsp, iip)
Perform a Bluetooth Inquiry using the device name, or the first
available device if NULL is passed. The inquiry length will be
timeout seconds, and the number of responses (up to a limit of
max_rsp) will be returned. A pointer to an array of bt_devinquiry
structures, defined as:
struct bt_devinquiry {
bdaddr_t bdaddr;
uint8_t pscan_rep_mode;
uint8_t pscan_period_mode;
uint8_t dev_class[3];
uint16_t clock_offset;
int8_t rssi;
uint8_t data[240];
};
will be stored in the location given by iip and this should be
released after use with free(3).
RETURN VALUES
These Bluetooth device access routines return -1 on failure, and errno
will be set to indicate the error.
ERRORS
In addition to errors returned by the standard C library IO functions,
the following errors may be indicated by device access routines.
[EINVAL] A provided function argument was not valid.
[EIO] A device response was not properly understood.
[ETIMEDOUT] An operation exceeded the given time limit.
SEE ALSObluetooth(3)HISTORY
The Bluetooth device access API was created by Maksim Yevmenkin and first
appeared in FreeBSD. This implementation written for NetBSD by Iain
Hibbert.
BSD October 25, 2011 BSD
