bt_gethostbyname
,
bt_gethostbyaddr
,
bt_gethostent
, bt_sethostent
,
bt_endhostent
,
bt_getprotobyname
,
bt_getprotobynumber
,
bt_getprotoent
,
bt_setprotoent
,
bt_endprotoent
, bt_aton
,
bt_ntoa
, bt_devaddr
,
bt_devname
, bt_devinfo
,
bt_devenum
, bt_devopen
,
bt_devclose
, 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
,
bt_devremote_name
,
bt_devremote_name_gen
,
bdaddr_same
, bdaddr_any
,
bdaddr_copy
—
Bluetooth routines
Bluetooth Library (libbluetooth, -lbluetooth)
#include <bluetooth.h>
struct hostent *
bt_gethostbyname
(const
char *name);
struct hostent *
bt_gethostbyaddr
(const
char *addr, int
len, int type);
struct hostent *
bt_gethostent
(void);
void
bt_sethostent
(int
stayopen);
void
bt_endhostent
(void);
struct protoent *
bt_getprotobyname
(const
char *name);
struct protoent *
bt_getprotobynumber
(int
proto);
struct protoent *
bt_getprotoent
(void);
void
bt_setprotoent
(int
stayopen);
void
bt_endprotoent
(void);
int
bt_aton
(const
char *str, bdaddr_t
*ba);
const char *
bt_ntoa
(const
bdaddr_t *ba, char
*str);
int
bt_devaddr
(const
char *devname, bdaddr_t
*addr);
int
bt_devname
(char
*devname, const bdaddr_t
*addr);
int
(bt_devenum_cb_t)
(int
s, struct bt_devinfo
const *di, void
*arg);
int
bt_devinfo
(struct
bt_devinfo *di);
int
bt_devenum
(bt_devenum_cb_t
*cb, void
*arg);
int
bt_devopen
(char
const *devname);
int
bt_devclose
(int
s);
int
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 to);
int
bt_devreq
(int
s, struct bt_devreq
*r, time_t to);
int
bt_devfilter
(int
s, struct bt_devfilter
const *new, struct
bt_devfilter *old);
void
bt_devfilter_pkt_set
(struct
bt_devfilter *filter,
uint8_t type);
void
bt_devfilter_pkt_clt
(struct
bt_devfilter *filter,
uint8_t type);
int
bt_devfilter_pkt_tst
(struct
bt_devfilter const *filter,
uint8_t type);
void
bt_devfilter_evt_set
(struct
bt_devfilter *filter,
uint8_t event);
void
bt_devfilter_evt_clt
(struct
bt_devfilter *filter,
uint8_t event);
int
bt_devfilter_evt_tst
(struct
bt_devfilter const *filter,
uint8_t event);
int
bt_devinquiry
(char
const *devname, time_t
length, int
num_rsp, struct
bt_devinquiry **ii);
char *
bt_devremote_name
(char
const *devname, const
bdaddr_t *remote, time_t
to, uint16_t
clk_off, uint8_t
ps_rep_mode, uint8_t
ps_mode);
char *
bt_devremote_name_gen
(char
const *btooth_devname,
const bdaddr_t
*remote);
int
bdaddr_same
(const
bdaddr_t *a, const
bdaddr_t *b);
int
bdaddr_any
(const
bdaddr_t *a);
int
bdaddr_copy
(const
bdaddr_t *dst, const
bdaddr_t *src);
The bt_gethostent
(),
bt_gethostbyname
() and
bt_gethostbyaddr
() functions each return a pointer to
an object with the hostent structure describing a
Bluetooth host referenced by name or by address, respectively.
The name argument passed to
bt_gethostbyname
() should point to a
NUL
-terminated hostname. The
addr argument passed to
bt_gethostbyaddr
() should point to an address which
is len bytes long, in binary form (i.e., not a
Bluetooth BD_ADDR in human readable ASCII form). The
type argument specifies the address family of this
address and must be set to AF_BLUETOOTH
.
The structure returned contains the information obtained from a
line in /etc/bluetooth/hosts file.
The bt_sethostent
() function controls
whether /etc/bluetooth/hosts file should stay open
after each call to bt_gethostbyname
() or
bt_gethostbyaddr
(). If the
stayopen flag is non-zero, the file will not be
closed.
The bt_endhostent
() function closes the
/etc/bluetooth/hosts file.
The bt_getprotoent
(),
bt_getprotobyname
() and
bt_getprotobynumber
() functions each return a
pointer to an object with the protoent structure
describing a Bluetooth Protocol Service Multiplexor referenced by name or
number, respectively.
The name argument passed to
bt_getprotobyname
() should point to a
NUL
-terminated Bluetooth Protocol Service
Multiplexor name. The proto argument passed to
bt_getprotobynumber
() should have numeric value of
the desired Bluetooth Protocol Service Multiplexor.
The structure returned contains the information obtained from a
line in /etc/bluetooth/protocols file.
The bt_setprotoent
() function controls
whether /etc/bluetooth/protocols file should stay
open after each call to bt_getprotobyname
() or
bt_getprotobynumber
(). If the
stayopen flag is non-zero, the file will not be
closed.
The bt_endprotoent
() function closes the
/etc/bluetooth/protocols file.
The bt_aton
() routine interprets the
specified character string as a Bluetooth address, placing the address into
the structure provided. It returns 1 if the string was successfully
interpreted, or 0 if the string is invalid.
The routine bt_ntoa
() takes a Bluetooth
address and places an ASCII string representing the address into the buffer
provided. It is up to the caller to ensure that provided buffer has enough
space. If no buffer was provided then internal static buffer will be
used.
The bt_devaddr
() function interprets the
specified devname string as the address or device name
of a Bluetooth device on the local system, and places the device address in
the provided bdaddr, if any. The function returns 1 if
the string was successfully interpreted, or 0 if the string did not match
any local device. The bt_devname
() function takes a
Bluetooth device address and copies the local device name associated with
that address into the buffer provided, if any. Caller must ensure that
provided buffer is at least HCI_DEVNAME_SIZE
characters in size. The function returns 1 when the device was found,
otherwise 0.
The bt_devinfo
() function populates
provided bt_devinfo structure with the information
about given Bluetooth device. The caller is expected to pass Bluetooth
device name in the devname field of the passed
bt_devinfo structure. The function returns 0 when
successful, otherwise -1. The bt_devinfo structure is
defined as follows
struct bt_devinfo
{
char devname[HCI_DEVNAME_SIZE];
uint32_t state;
bdaddr_t bdaddr;
uint16_t _reserved0;
uint8_t features[HCI_DEVFEATURES_SIZE];
/* buffer info */
uint16_t _reserved1;
uint16_t cmd_free;
uint16_t sco_size;
uint16_t sco_pkts;
uint16_t sco_free;
uint16_t acl_size;
uint16_t acl_pkts;
uint16_t acl_free;
/* stats */
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;
/* misc/specific */
uint16_t link_policy_info;
uint16_t packet_type_info;
uint16_t role_switch_info;
uint16_t debug;
uint8_t _padding[20];
};
The bt_devenum
() function enumerates
Bluetooth devices present in the system. For every device found, the
function will call provided cb callback function which
should be of bt_devenum_cb_t type. The callback
function is passed a HCI
socket
s, fully populated bt_devinfo
structure di and arg argument
provided to the bt_devenum
(). The callback function
can stop enumeration by returning a value that is greater than zero. The
function returns number of successfully enumerated devices, or -1 if an
error occurred.
The bt_devopen
() function opens a
Bluetooth device with the given devname and returns a
connected and bound HCI
socket handle. The function
returns -1 if an error has occurred.
The bt_devclose
() closes the passed
HCI
socket handle s,
previously obtained with
bt_devopen(3).
The bt_devsend
() function sends a
Bluetooth HCI
command with the given
opcode to the provided socket s,
previously obtained with
bt_devopen(3).
The opcode parameter is expected to be in the host
byte order. The param and plen
parameters specify command parameters. The
bt_devsend
() function does not modify the
HCI
filter on the provided socket
s. The function returns 0 on success, or -1 if an
error occurred.
The bt_devrecv
() function receives one
Bluetooth HCI
packet from the socket
s, previously obtained with
bt_devopen(3).
The packet is placed into the provided buffer buf of
size size. The to parameter
specifies receive timeout in seconds. Infinite timeout can be specified by
passing negative value in the to parameter. The
bt_devrecv
() function does not modify the
HCI
filter on the provided socket
s. The function returns total number of bytes
received, or -1 if an error occurred.
The bt_devreq
() function makes a Bluetooth
HCI
request to the socket s,
previously obtained with
bt_devopen(3).
The function will send the specified command and will wait for the specified
event, or timeout to seconds to occur. The
bt_devreq structure is defined as follows
struct bt_devreq
{
uint16_t opcode;
uint8_t event;
void *cparam;
size_t clen;
void *rparam;
size_t rlen;
};
The opcode field specifies the command and
is expected to be in the host byte order. The cparam
and clen fields specify command parameters data and
command parameters data size respectively. The event
field specifies which Bluetooth HCI
event ID the
function should wait for, otherwise it should be set to zero. The
HCI
Command Complete and Command Status events are
enabled by default. The rparam and
rlen parameters specify buffer and buffer size
respectively where return parameters should be placed. The
bt_devreq
() function temporarily modifies filter on
the provided HCI
socket s. The
function returns 0 on success, or -1 if an error occurred.
The bt_devfilter
() controls the local
HCI
filter associated with the socket
s, previously obtained with
bt_devopen(3).
Filtering can be done on packet types, i.e. ACL
,
SCO
or HCI
, command and
event packets, and, in addition, on HCI
event IDs.
Before applying the new filter (if provided) the
function will try to obtain the current filter from the socket
s and place it into the old
parameter (if provided). The function returns 0 on success, or -1 if an
error occurred.
The bt_devfilter_pkt_set
(),
bt_devfilter_pkt_clr
() and
bt_devfilter_pkt_tst
() functions can be used to
modify and test the HCI
filter
filter. The type parameter
specifies HCI
packet type.
The bt_devfilter_evt_set
(),
bt_devfilter_evt_clr
() and
bt_devfilter_evt_tst
() functions can be used to
modify and test the HCI
event filter
filter. The event parameter
specifies HCI
event ID.
The bt_devinquiry
() function performs
Bluetooth inquiry. The devname parameter specifies
which local Bluetooth device should perform an inquiry. If not specified,
i.e. NULL
, then first available device will be used.
The length parameters specifies the total length of an
inquiry in seconds. If not specified, i.e. 0, default value will be used.
The num_rsp parameter specifies the number of
responses that can be received before the inquiry is halted. If not
specified, i.e. 0, default value will be used. The ii
parameter specifies where to place inquiry results. On success, the function
will return total number of inquiry results, will allocate, using
calloc(3),
buffer to store all the inquiry results and will return pointer to the
allocated buffer in the ii parameter. It is up to the
caller of the function to dispose of the buffer using
free(3)
call. The function returns -1 if an error has occurred. The
bt_devinquiry structure is defined as follows
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];
};
The bt_devremote_name
() function performs
Bluetooth Remote Name Request procedure to obtain the user-friendly name of
another Bluetooth unit. The devname parameter
specifies which local Bluetooth device should perform the request. If not
specified (NULL
), the first available device is
used. The remote parameter specifies the Bluetooth
BD_ADDR of the remote device to query. The to
parameter specifies response timeout in seconds. If not specified (0), the
default value is taken from the net.bluetooth.hci.command_timeout
sysctl(8)
value. The clk_off, ps_rep_mode,
and ps_mode parameters specify Clock_Offset,
Page_Scan_Repetition_Mode, and Page_Scan_Mode fields of
HCI_Remote_Name_Request respectively. On success, the function returns a
pointer to dynamically allocated NUL-terminated string or
NULL
if an error occurred. It is up to the caller to
release returned string using
free(3).
The bt_devremote_name_gen
() function is a
shortcut to bt_devremote_name
() that passes generic
defaults for to, clk_off,
ps_rep_mode, and ps_mode
parameters.
The bdaddr_same
(),
bdaddr_any
(), and
bdaddr_copy
() are handy shorthand Bluetooth address
utility functions. The bdaddr_same
() function will
test if two provided BD_ADDRs are the same. The
bdaddr_any
() function will test if provided BD_ADDR
is ANY
BD_ADDR. The
bdaddr_copy
() function will copy provided
src BD_ADDR into provided dst
BD_ADDR.
- /etc/bluetooth/hosts
-
- /etc/bluetooth/protocols
-
Print out the hostname associated with a specific BD_ADDR:
const char *bdstr = "00:01:02:03:04:05";
bdaddr_t bd;
struct hostent *hp;
if (!bt_aton(bdstr, &bd))
errx(1, "can't parse BD_ADDR %s", bdstr);
if ((hp = bt_gethostbyaddr((const char *)&bd,
sizeof(bd), AF_BLUETOOTH)) == NULL)
errx(1, "no name associated with %s", bdstr);
printf("name associated with %s is %s\n", bdstr, hp->h_name);
Error return status from bt_gethostent
(),
bt_gethostbyname
() and
bt_gethostbyaddr
() is indicated by return of a
NULL
pointer. The external integer
h_errno may then be checked to see whether this is a
temporary failure or an invalid or unknown host. The routine
herror(3)
can be used to print an error message describing the failure. If its argument
string is non-NULL
, it is
printed, followed by a colon and a space. The error message is printed with a
trailing newline.
The variable h_errno can have the following
values:
HOST_NOT_FOUND
- No such host is known.
NO_RECOVERY
- Some unexpected server failure was encountered. This is a non-recoverable
error.
The bt_getprotoent
(),
bt_getprotobyname
() and
bt_getprotobynumber
() return
NULL
on EOF or error.
The bt_gethostent
() function reads the next line of
/etc/bluetooth/hosts, opening the file if necessary.
The bt_sethostent
() function opens and/or
rewinds the /etc/bluetooth/hosts file.
The bt_getprotoent
() function reads the
next line of /etc/bluetooth/protocols, opening the
file if necessary.
The bt_setprotoent
() function opens and/or
rewinds the /etc/bluetooth/protocols file.
The bt_devenum
() function enumerates up to
HCI_DEVMAX
Bluetooth devices. During enumeration the
bt_devenum
() function uses the same
HCI
socket. The function guarantees that the socket,
passed to the callback function, will be bound and connected to the
Bluetooth device being enumerated.
Some of those functions use static data storage; if the data is needed for
future use, it should be copied before any subsequent calls overwrite it.