Unix/Linux Go Back    


NetBSD 6.1.5 - man page for sdp_get_data (netbsd section 3)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


SDP_DATA(3)			   BSD Library Functions Manual 		      SDP_DATA(3)

NAME
     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

LIBRARY
     library ``libbluetooth''

SYNOPSIS
     #include <sdp.h>

     extern const uuid_t BLUETOOTH_BASE_UUID;

     bool
     sdp_match_uuid16(sdp_data_t *data, uint16_t uuid);

     bool
     sdp_get_data(sdp_data_t *data, sdp_data_t *value);

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

     bool
     sdp_get_uuid(sdp_data_t *data, uuid_t *uuid);

     bool
     sdp_get_bool(sdp_data_t *data, bool *value);

     bool
     sdp_get_seq(sdp_data_t *data, sdp_data_t *seq);

     bool
     sdp_get_alt(sdp_data_t *data, sdp_data_t *alt);

     bool
     sdp_get_uint(sdp_data_t *data, uintmax_t *value);

     bool
     sdp_get_int(sdp_data_t *data, intmax_t *value);

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

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

     bool
     sdp_put_data(sdp_data_t *data, sdp_data_t *value);

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

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

     bool
     sdp_put_uuid16(sdp_data_t *data, uint16_t value);

     bool
     sdp_put_uuid32(sdp_data_t *data, uint32_t value);

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

     bool
     sdp_put_bool(sdp_data_t *data, bool value);

     bool
     sdp_put_uint(sdp_data_t *data, uintmax_t value);

     bool
     sdp_put_uint8(sdp_data_t *data, uint8_t value);

     bool
     sdp_put_uint16(sdp_data_t *data, uint16_t value);

     bool
     sdp_put_uint32(sdp_data_t *data, uint32_t value);

     bool
     sdp_put_uint64(sdp_data_t *data, uint64_t value);

     bool
     sdp_put_int(sdp_data_t *data, intmax_t value);

     bool
     sdp_put_int8(sdp_data_t *data, int8_t value);

     bool
     sdp_put_int16(sdp_data_t *data, int16_t value);

     bool
     sdp_put_int32(sdp_data_t *data, int32_t value);

     bool
     sdp_put_int64(sdp_data_t *data, int64_t value);

     bool
     sdp_put_seq(sdp_data_t *data, ssize_t length);

     bool
     sdp_put_alt(sdp_data_t *data, ssize_t length);

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

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

     bool
     sdp_set_bool(const sdp_data_t *data, bool value);

     bool
     sdp_set_uint(const sdp_data_t *data, uintmax_t value);

     bool
     sdp_set_int(const sdp_data_t *data, intmax_t value);

     bool
     sdp_set_seq(const sdp_data_t *data, ssize_t length);

     ssize_t
     sdp_data_size(const sdp_data_t *data);

     int
     sdp_data_type(const sdp_data_t *data);

     bool
     sdp_data_valid(const sdp_data_t *data);

     void
     sdp_data_print(const sdp_data_t *data, int indent);

DESCRIPTION
     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 0x0100.

     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 function:

     The sdp_match_uuid16() routine examines the next data element in the data buffer for an ele-
	     ment 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.

EXAMPLES
     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);
			     break;

		     case SDP_ATTR_PROFILE_DESCRIPTOR_LIST:
			     printf("ProfileDescriptorList:\n");
			     sdp_data_print(&val, 0);
			     break;

		     default:
			     printf("uninteresting attribute 0x%04x\n", attr);
			     break;
		     }
	     }

     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_seq_seq() will only modify the content, not the size of the header.

SEE ALSO
     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/"

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

BSD					 January 15, 2011				      BSD
Unix & Linux Commands & Man Pages : ©2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 11:14 AM.