Manual Pages for UNIX Operating System command usage for man usb_parse_data

Kernel Functions for Drivers                   usb_parse_data(9F)



NAME
     usb_parse_data  -  Tokenize  and  align  the  bytes  of  raw
     variable-format data

SYNOPSIS
     #include 

     size_t usb_parse_data(char *format, uchar_t *data,
          size_t datalen, void *structure, size_t structlen);


INTERFACE LEVEL
     Solaris DDI specific (Solaris DDI)

PARAMETERS
     format       Null terminated string describing the format of
                  the  data  structure  for  general-purpose byte
                  swapping. The letters "c," "s,"  "l,"  and  "L"
                  represent  1,  2,  4  and  8  byte  quantities,
                  respectively. A descriptor that consists  of  a
                  short  and  two  bytes  would  be  described by
                  "scc." A number preceding a letter serves as  a
                  multiplier  of that letter. A format equivalent
                  to "scc" is "s2c."


     data         Raw descriptor data to parse.


     datalen      Length, in bytes, of the  raw  descriptor  data
                  buffer.


     structure    Destination data buffer where  parsed  data  is
                  returned.


     structlen    Length,  in  bytes,  of  the  destination  data
                  buffer.  Parsed  result  length will not exceed
                  this value.


DESCRIPTION
     The usb_parse_data function parses data such as a  variable-
     format  class-  or  vendor-specific descriptor. The function
     also tokenizes and aligns the bytes of raw  descriptor  data
     into fields of a variable-format descriptor.


     While the USBA framework can parse the endpoint,  interface,
     configuration, and string descriptors defined by the USB 2.0
     specification,  the  format  of  class-  or  vendor-specific



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Kernel Functions for Drivers                   usb_parse_data(9F)



     descriptors  cannot  be explicitly defined by the specifica-
     tion and will  be  unique  for  each.  The  format  argument
     defines how to parse such a descriptor.


     While the USB specification defines bit ordering as  little-
     endian,  this  routine  (like  the entire API), converts the
     data to the endianness of the host.


     The structlen parameter defines the size of the  destination
     data  buffer. Data is truncated to this size if the destina-
     tion data buffer is too small.

RETURN VALUES
     On success: Returns the size (in bytes) of the  parsed  data
     result.


     On failure: Returns 0. (Same as USB_PARSE_ERROR).

CONTEXT
     May be called from user, kernel or interrupt context.

EXAMPLES
         /*
          * Parse raw descriptor data in buf, putting result into ret_descr.
          * ret_buf_len holds the size of ret_descr buf;  routine returns
          * number of resulting bytes.
          *
          * Descriptor being parsed has 2 chars, followed by one short,
          * 3 chars and one more short.
          */
         size_t size_of_returned_descr;
         xxx_descr_t ret_descr;

          size_of_returned_descr = usb_parse_data("ccscccs",
             buf, sizeof(buf), (void *)ret_descr, (sizeof)xxx_descr_t));
         if (size_of_returned_descr < (sizeof (xxx_descr_t))) {
                  /* Data truncated. */
         }

         or:

         size_of_returned_descr = usb_parse_data("2cs3cs",
             buf, sizeof(buf), (void *)ret_descr, (sizeof)xxx_descr_t));
         if (size_of_returned_descr < (sizeof (xxx_descr_t))) {
                 /* Data truncated. */
         }






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Kernel Functions for Drivers                   usb_parse_data(9F)



ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Architecture                | PCI-based systems           |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | Availability                | driver/usb                  |
    |_____________________________|_____________________________|


SEE ALSO
     attributes(5),                         usb_get_dev_data(9F),
     usb_get_string_descr(9F), usb_get_cfg(9F)



































SunOS 5.11           Last change: 5 Jan 2004                    3