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SDP_DATA(3)                Library Functions Manual                SDP_DATA(3)

     sdp_match_uuid16 sdp_get_data sdp_get_attr sdp_get_uuid sdp_get_bool
     sdp_get_seq sdp_get_alt sdp_get_uint sdp_get_int sdp_get_str sdp_get_url
     sdp_put_data sdp_put_attr sdp_put_uuid sdp_put_uuid16 sdp_put_uuid32
     sdp_put_uuid128 sdp_put_bool sdp_put_uint sdp_put_uint8 sdp_put_uint16
     sdp_put_uint32 sdp_put_uint64 sdp_put_int sdp_put_int8 sdp_put_int16
     sdp_put_int32 sdp_put_int64 sdp_put_seq sdp_put_alt sdp_put_str
     sdp_put_url sdp_set_bool sdp_set_uint sdp_set_int sdp_set_seq sdp_set_alt
     sdp_data_size sdp_data_type sdp_data_valid sdp_data_print - Service
     Discovery Protocol data manipulation routines

     Bluetooth Library (libbluetooth, -lbluetooth)

     #include <sdp.h>

     extern const uuid_t BLUETOOTH_BASE_UUID;

     sdp_match_uuid16(sdp_data_t *data, uint16_t uuid);

     sdp_get_data(sdp_data_t *data, sdp_data_t *value);

     sdp_get_attr(sdp_data_t *data, uint16_t *attr, sdp_data_t *value);

     sdp_get_uuid(sdp_data_t *data, uuid_t *uuid);

     sdp_get_bool(sdp_data_t *data, bool *value);

     sdp_get_seq(sdp_data_t *data, sdp_data_t *seq);

     sdp_get_alt(sdp_data_t *data, sdp_data_t *alt);

     sdp_get_uint(sdp_data_t *data, uintmax_t *value);

     sdp_get_int(sdp_data_t *data, intmax_t *value);

     sdp_get_str(sdp_data_t *data, char **str, size_t *length);

     sdp_get_url(sdp_data_t *data, char **url, size_t *length);

     sdp_put_data(sdp_data_t *data, sdp_data_t *value);

     sdp_put_attr(sdp_data_t *data, uint16_t attr, sdp_data_t *value);

     sdp_put_uuid(sdp_data_t *data, const uuid_t *value);

     sdp_put_uuid16(sdp_data_t *data, uint16_t value);

     sdp_put_uuid32(sdp_data_t *data, uint32_t value);

     sdp_put_uuid128(sdp_data_t *data, const uuid_t *value);

     sdp_put_bool(sdp_data_t *data, bool value);

     sdp_put_uint(sdp_data_t *data, uintmax_t value);

     sdp_put_uint8(sdp_data_t *data, uint8_t value);

     sdp_put_uint16(sdp_data_t *data, uint16_t value);

     sdp_put_uint32(sdp_data_t *data, uint32_t value);

     sdp_put_uint64(sdp_data_t *data, uint64_t value);

     sdp_put_int(sdp_data_t *data, intmax_t value);

     sdp_put_int8(sdp_data_t *data, int8_t value);

     sdp_put_int16(sdp_data_t *data, int16_t value);

     sdp_put_int32(sdp_data_t *data, int32_t value);

     sdp_put_int64(sdp_data_t *data, int64_t value);

     sdp_put_seq(sdp_data_t *data, ssize_t length);

     sdp_put_alt(sdp_data_t *data, ssize_t length);

     sdp_put_str(sdp_data_t *data, const char *str, ssize_t length);

     sdp_put_url(sdp_data_t *data, const char *url, ssize_t length);

     sdp_set_bool(const sdp_data_t *data, bool value);

     sdp_set_uint(const sdp_data_t *data, uintmax_t value);

     sdp_set_int(const sdp_data_t *data, intmax_t value);

     sdp_set_seq(const sdp_data_t *data, ssize_t length);

     sdp_data_size(const sdp_data_t *data);

     sdp_data_type(const sdp_data_t *data);

     sdp_data_valid(const sdp_data_t *data);

     sdp_data_print(const sdp_data_t *data, int indent);

     These routines provide for the manipulation of Service Discovery Protocol
     data buffers.  An SDP data buffer type is defined as:

           typedef struct {
                   uint8_t *next;
                   uint8_t *end;
           } sdp_data_t;

     Where next points to the next available byte, and end points to the first
     address past end of the data area, such that "end = next + length".

     The SDP data consists of byte streams describing data elements, where a
     data element is a typed data representation consisting of a header field
     and a data field.  The header field consists of type and size
     descriptors, and the data field is a sequence of bytes whose length is
     specified in the size descriptor and whose content is specified by the
     type descriptor.  For instance, the byte sequence "0x09, 0x01, 0x00"
     describes an 16-bit unsigned integer element (type 0x09) with value of

     Data element types including signed and unsigned integers, boolean,
     string, sequence and alternative lists are defined in the <sdp.h> include
     file.  See the "Service Discovery Protocol" chapters of the "Bluetooth
     Core Specifications" for more information.

     To reduce the burden of storing and transferring 128-bit UUID values, a
     range of UUID values has been pre-allocated for assignment to often-used,
     registered purposes.  The first UUID in this pre-allocated range is known
     as the "Bluetooth Base UUID", defined in the "Bluetooth Assigned Numbers"
     document and declared in <sdp.h> as const uuid_t BLUETOOTH_BASE_UUID;

     The data manipulation routines are arranged into major groups by

     The sdp_match_uuid16() routine examines the next data element in the data
             buffer for an element of type UUID that matches the Bluetooth
             short alias UUID with 16-bit value given.  If the UUID matches,
             the function will return true and the next field of the SDP data
             buffer will be advanced to the next element.  Otherwise false
             will be returned.

     The sdp_get_xxxx() routines examine the next data element in the data
             buffer for an element of the given type.  If the type matches,
             the function will extract the typed value to the address given
             and advance the next field of the SDP data buffer to the next
             element then return true.  Otherwise false will be returned.
             Note, these functions will not modify the data argument unless
             the correct type was found, and will update the data argument
             first to allow discarding in the case where a sdp_data_t was
             being returned.

     The sdp_put_xxxx() routines will attempt to write a data element of the
             given type and value to the data buffer.  If the data buffer is
             too small to contain the encoded data element, the function will
             return false, otherwise true will be returned and the next field
             of the SDP data pointer will be advanced.  In the case of
             sdp_put_seq() and sdp_put_alt(), the length argument may be -1,
             in which case the generated sequence header will describe all the
             remaining buffer space.  For sdp_put_str() and sdp_put_url() the
             length argument may be -1 in which case the string pointer is
             treated as nul terminated.

     The sdp_set_xxxx() routines examine the SDP data buffer for a data
             element of the given type, and replace the content with the
             passed value.  If the next data element in the buffer is not of
             the appropriate type, the function will return false, otherwise
             true will be returned and the value updated.  In the case of
             sdp_set_seq() and sdp_set_alt(), the length argument may be -1,
             in which case the sequence header will be adjusted to describe
             the entire data space where possible.

     The sdp_data_xxxx() routines include various functions to provide
             information about the data stream such as sdp_data_size() to
             return the size of the next data element, and sdp_data_type() to
             return the type of the next data element.  sdp_data_valid() can
             be used to ensure that the entire data buffer contains valid SDP
             data elements and that all of the elements are contained exactly
             within the data buffer.  Finally, sdp_data_print() will print the
             data buffer in human readable format.

     To parse a ServiceAttribute response obtained from a remote server using
     sdp_service_attribute(3), examining various attribute values:

             sdp_data_t rsp, val;
             uint16_t attr;
             uintmax_t handle;

             /* rsp contains remote response */

             while (sdp_get_attr(&rsp, &attr, &val)) {
                     switch(attr) {
                     case SDP_ATTR_SERVICE_RECORD_HANDLE:
                             sdp_get_uint(&val, &handle);
                             printf("ServiceRecordHandle: 0x%08x\n", handle);

                     case SDP_ATTR_PROFILE_DESCRIPTOR_LIST:
                             sdp_data_print(&val, 0);

                             printf("uninteresting attribute 0x%04x\n", attr);

     The following code creates a ProtocolDataList attribute value for a
     service using the L2CAP and RFCOMM protocols and illustrates how to
     construct sequences of known and unknown length.

             uint8_t buf[SIZE];
             sdp_data_t seq;
             uint16_t psm;
             uint8_t channel;

             seq.next = buf;
             seq.end = buf + sizeof(buf);
             sdp_put_seq(&seq, -1);

             sdp_put_seq(&seq, 6);
             sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_L2CAP);
             sdp_put_uint16(&seq, psm);

             sdp_put_seq(&seq, 5);
             sdp_put_uuid16(&seq, SDP_UUID_PROTOCOL_RFCOMM);
             sdp_put_uint8(&seq, channel);

             seq.end = seq.next;
             seq.next = buf;
             sdp_set_seq(&seq, -1);

     Note that although SIZE is assumed to be large enough to contain the
     entire sequence in this case, the sdp_put_xxxx() routines will not
     overflow the buffer area or write partial data.

     The encoded data stream will be stored in a space efficient manner where
     possible.  In the above example, it is known that the data element
     sequence containing the L2CAP UUID will be 8 bytes long overall since the
     container length of 6 can be stored in a single byte.  But, because the
     value of SIZE is unknown, the overall length of the ProtocolDataList may
     vary depending if 8, 16 or 32 bits were needed to represent the original
     buffer size.  sdp_set_seq() will only modify the content, not the size of
     the header.

     sdpquery(1), bluetooth(3), sdp(3), uuid(3), sdpd(8)

     The "Service Discovery Protocol" section of the Bluetooth Core
     specifications, available at http://www.bluetooth.com/

     These SDP data parsing and manipulation functions first appeared in
     NetBSD 6.0.

NetBSD 10.99                   January 15, 2011                   NetBSD 10.99