Difference between revisions of "Binary Module"

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=Text Decoding and Encoding=
 
=Text Decoding and Encoding=
The following encodings are supported by Java 7
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The following encodings are supported by any Java 7 Implementation
([http://docs.oracle.com/javase/7/docs/api/java/nio/charset/Charset.html| Java Charset Documentation]), hence may be used as values for {Code|$encoding}:
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([http://docs.oracle.com/javase/7/docs/api/java/nio/charset/Charset.html Java Charset Documentation]), hence may be used as values for {{Code|$encoding}}:
 
"US-ASCII", "ISO-8859-1", "UTF-8". "UTF-16BE", UTF-16LE", "UTF-16".
 
"US-ASCII", "ISO-8859-1", "UTF-8". "UTF-16BE", UTF-16LE", "UTF-16".
  

Revision as of 21:00, 29 July 2014

This XQuery Module contains functions to process binary data, including extracting subparts, searching, basic binary operations and conversion between binary and structured forms.

This module is based on the EXPath Binary Module.

Conventions

All functions and errors in this module are assigned to the http://expath.org/ns/binary namespace, which is statically bound to the bin prefix.

Constants and Conversions

bin:hex

Signatures bin:hex($in as xs:string?) as xs:base64Binary?
Summary Returns the binary form of the set of octets written as a sequence of (ASCII) hex digits ([0-9A-Fa-f]).
$in will be effectively zero-padded from the left to generate an integral number of octets, i.e. an even number of hexadecimal digits. If $in is an empty string, then the result will be an xs:base64Binary with no embedded data. Byte order in the result follows (per-octet) character order in the string. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors non-numeric-character: the input cannot be parsed as a hexadecimal number.
Examples bin:hex('11223F4E') yields ESI/Tg==.
xs:hexBinary(bin:hex('FF')) yields FF.

bin:bin

Signatures bin:bin($in as xs:string?) as xs:base64Binary?
Summary Returns the binary form of the set of octets written as a sequence of (8-wise) (ASCII) binary digits ([01]).
$in will be effectively zero-padded from the left to generate an integral number of octets. If $in is an empty string, then the result will be an xs:base64Binary with no embedded data. Byte order in the result follows (per-octet) character order in the string. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors non-numeric-character: the input cannot be parsed as a binary number.
Examples bin:bin('1101000111010101') yields 0dU=.
xs:hexBinary(bin:bin('1000111010101')) yields 11D5.

bin:octal

Signatures bin:octal($in as xs:string?) as xs:base64Binary?
Summary Returns the binary form of the set of octets written as a sequence of (ASCII) octal digits ([0-7]).
$in will be effectively zero-padded from the left to generate an integral number of octets. If $in is an empty string, then the result will be an xs:base64Binary with no embedded data. Byte order in the result follows (per-octet) character order in the string. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors non-numeric-character: the input cannot be parsed as an octal number.
Examples xs:hexBinary(bin:octal('11223047')) yields 252627.

bin:to-octets

Signatures bin:to-octets($in as xs:base64Binary) as xs:integer*
Summary Returns binary data as a sequence of octets.
If $in is a zero length binary data then the empty sequence is returned. Octets are returned as integers from 0 to 255.

bin:from-octets

Signatures bin:from-octets($in as xs:integer*) as xs:base64Binary
Summary Converts a sequence of octets into binary data.
Octets are integers from 0 to 255. If the value of $in is the empty sequence, the function returns zero-sized binary data.
Errors octet-out-of-range: one of the octets lies outside the range 0 - 255.

Basic Operations

bin:hex

Signatures bin:length($in as xs:base64Binary) as xs:integer
Summary Returns the size of binary data in octets.

bin:part

Signatures bin:part($in as xs:base64Binary?, $offset as xs:integer) as xs:base64Binary?
bin:part($in as xs:base64Binary?, $offset as xs:integer, $size as xs:integer) as xs:base64Binary?
Summary Returns a section of binary data starting at the $offset octet.
If $size is specified, the size of the returned binary data is $size octets. If $size is absent, all remaining data from $offset is returned. The $offset is zero based. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors negative-size: the specified size is negative.
index-out-of-range: the specified offset + size is out of range.
Examples Test whether binary data starts with binary content consistent with a PDF file:
bin:part($data, 0, 4) eq bin:hex("25504446").

bin:join

Signatures bin:join($in as xs:base64Binary*) as xs:base64Binary
Summary Returns an xs:base64Binary created by concatenating the items in the sequence $in, in order. If the value of $in is the empty sequence, the function returns a binary item containing no data bytes.

bin:insert-before

Signatures bin:insert-before($in as xs:base64Binary?, $offset as xs:integer, $extra as xs:base64Binary?) as xs:base64Binary?
Summary Returns binary data consisting sequentially of the data from $in up to and including the $offset - 1 octet, followed by all the data from $extra, and then the remaining data from $in.
The $offset is zero based. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors index-out-of-range: the specified offset is out of range.

bin:pad-left

Signatures bin:pad-left($in as xs:base64Binary?, $size as xs:integer) as xs:base64Binary?
bin:pad-left($in as xs:base64Binary?, $size as xs:integer, $octet as xs:integer) as xs:base64Binary?
Summary Returns an xs:base64Binary created by padding the input with $size octets in front of the input. If $octet is specified, the padding octets each have that value, otherwise they are zero.
If the value of $in is the empty sequence, the function returns an empty sequence.
Errors negative-size: the specified size is negative.
octet-out-of-range: the specified octet lies outside the range 0-255.

bin:pad-right

Signatures bin:pad-right($in as xs:base64Binary?, $size as xs:integer) as xs:base64Binary?
bin:pad-right($in as xs:base64Binary?, $size as xs:integer, $octet as xs:integer) as xs:base64Binary?
Summary Returns an xs:base64Binary created by padding the input with $size octets after the input. If $octet is specified, the padding octets each have that value, otherwise they are zero.
If the value of $in is the empty sequence, the function returns an empty sequence.
Errors negative-size: the specified size is negative.
octet-out-of-range: the specified octet lies outside the range 0-255.

bin:find

Signatures bin:find($in as xs:base64Binary?, $offset as xs:integer, $search as xs:base64Binary) as xs:integer?
Summary Returns the first location of the binary search sequence in the input, or if not found, the empty sequence.
The $offset and the returned location are zero based. If the value of $in is the empty sequence, the function returns an empty sequence.
Errors index-out-of-range: the specified offset + size is out of range.

Text Decoding and Encoding

The following encodings are supported by any Java 7 Implementation (Java Charset Documentation), hence may be used as values for $encoding: "US-ASCII", "ISO-8859-1", "UTF-8". "UTF-16BE", UTF-16LE", "UTF-16".

bin:decode-string

Signatures bin:decode-string($in as xs:base64Binary?, $encoding as xs:string) as xs:string?
bin:decode-string($in as xs:base64Binary?, $encoding as xs:string, $offset as xs:integer) as xs:string?
bin:decode-string($in as xs:base64Binary?, $encoding as xs:string, $offset as xs:integer, $size as xs:integer) as xs:string?
Summary Decodes binary data as a string in a given $encoding.
If $offset and $size are provided, the $size octets from $offset are decoded. If $offset alone is provided, octets from $offset to the end are decoded.If the value of $in is the empty sequence, the function returns an empty sequence.
Errors negative-size: the specified size is negative.
index-out-of-range: the specified offset + size is out of range.
unknown-encoding: the specified encoding is unknown.
conversion-error: an error or malformed input occurred during decoding the string.
Examples Tests whether the binary data starts with binary content consistent with a PDF file:
bin:decode-string($data, 'UTF-8', 0, 4) eq '%PDF'.

bin:encode-string

Signatures bin:encode-string($in as xs:string?, $encoding as xs:string) as xs:base64Binary?
Summary Encodes a string into binary data using a given $encoding.
If the value of $in is the empty sequence, the function returns an empty sequence.
Errors unknown-encoding: the specified encoding is unknown.
conversion-error: an error or malformed input occurred during encoding the string.

Packing and Unpacking of Numeric Values

The functions have an optional parameter $octet-order whose string value controls the order: Least-significant-first order is indicated by any of the values least-significant-first, little-endian, or LE. Most-significant-first order is indicated by any of the values most-significant-first, big-endian, or BE.

bin:pack-double

Signatures bin:pack-double($in as xs:double) as xs:base64Binary
bin:pack-double($in as xs:double, $octet-order as xs:string) as xs:base64Binary
Summary Returns the 8-octet binary representation of a double value.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified.
Errors unknown-significance-order: the specified octet order is unknown.

bin:pack-float

Signatures bin:pack-float($in as xs:double) as xs:base64Binary
bin:pack-float($in as xs:double, $octet-order as xs:string) as xs:base64Binary
Summary Returns the 4-octet binary representation of a float value.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified.
Errors unknown-significance-order: the specified octet order is unknown.

bin:pack-integer

Signatures bin:pack-integer($in as xs:double, $size as xs:integer) as xs:base64Binary
bin:pack-float($in as xs:double, $size as xs:integer, $octet-order as xs:string) as xs:base64Binary
Summary Returns the twos-complement binary representation of an integer value treated as $size octets long. Any 'excess' high-order bits are discarded.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified. Specifying a $size of zero yields an empty binary data.
Errors unknown-significance-order: the specified octet order is unknown.
negative-size: the specified size is negative.

bin:unpack-double

Signatures bin:unpack-double($in as xs:base64Binary, $offset as xs:integer) as xs:double
bin:unpack-double($in as xs:base64Binary, $offset as xs:integer, $octet-order as xs:string) as xs:double
Summary Extracts the double value stored at the particular offset in binary data.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified. The $offset is zero based.
Errors index-out-of-range: the specified offset is out of range.
unknown-significance-order: the specified octet order is unknown.

bin:unpack-float

Signatures bin:unpack-float($in as xs:base64Binary, $offset as xs:integer) as xs:double
bin:unpack-float($in as xs:base64Binary, $offset as xs:integer, $octet-order as xs:string) as xs:float
Summary Extracts the float value stored at the particular offset in binary data.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified. The $offset is zero based.
Errors index-out-of-range: the specified offset + size is out of range.
unknown-significance-order: the specified octet order is unknown.

bin:unpack-integer

Signatures bin:unpack-integer($in as xs:base64Binary, $offset as xs:integer, $size as xs:integer) as xs:double
bin:unpack-integer($in as xs:base64Binary, $offset as xs:integer, $size as xs:integer, $octet-order as xs:string) as xs:float
Summary Returns a signed integer value represented by the $size octets starting from $offset in the input binary representation. Necessary sign extension is performed (i.e. the result is negative if the high order bit is '1').
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified. The $offset is zero based. Specifying a $size of zero yields the integer 0.
Errors negative-size: the specified size is negative.
index-out-of-range: the specified offset + size is out of range.
unknown-significance-order: the specified octet order is unknown.

bin:unpack-unsigned-integer

Signatures bin:unpack-unsigned-integer($in as xs:base64Binary, $offset as xs:integer, $size as xs:integer) as xs:double
bin:unpack-unsigned-integer($in as xs:base64Binary, $offset as xs:integer, $size as xs:integer, $octet-order as xs:string) as xs:float
Summary Returns an unsigned integer value represented by the $size octets starting from $offset in the input binary representation.
Most-significant-octet-first number representation is assumed unless the $octet-order parameter is specified. The $offset is zero based. Specifying a $size of zero yields the integer 0.
Errors negative-size: the specified size is negative.
index-out-of-range: the specified offset + size is out of range.
unknown-significance-order: the specified octet order is unknown.

Bitwise Operations

bin:or

Signatures bin:or($a as xs:base64Binary?, $b as xs:base64Binary?) as xs:base64Binary?
Summary Returns the "bitwise or" of two binary arguments.
If either argument is the empty sequence, an empty sequence is returned.
Errors differing-length-arguments: the input arguments are of differing length.

bin:xor

Signatures bin:xor($a as xs:base64Binary?, $b as xs:base64Binary?) as xs:base64Binary?
Summary Returns the "bitwise xor" of two binary arguments.
If either argument is the empty sequence, an empty sequence is returned.
Errors differing-length-arguments: the input arguments are of differing length.

bin:and

Signatures bin:and($a as xs:base64Binary?, $b as xs:base64Binary?) as xs:base64Binary?
Summary Returns the "bitwise and" of two binary arguments.
If either argument is the empty sequence, an empty sequence is returned.
Errors differing-length-arguments: the input arguments are of differing length.

bin:not

Signatures bin:not($in as xs:base64Binary?) as xs:base64Binary?
Summary Returns the "bitwise not" of a binary argument.
If the argument is the empty sequence, an empty sequence is returned.

bin:shift

Signatures bin:shift($in as xs:base64Binary?, $by as xs:integer) as xs:base64Binary?
Summary Shifts bits in binary data.
If $by is zero, the result is identical to $in. If $by is positive then bits are shifted to the left. Otherwise, bits are shifted to the right. If the absolute value of $by is greater than the bit-length of $in then an all-zeros result is returned. The result always has the same size as $in. The shifting is logical: zeros are placed into discarded bits. If the value of $in is the empty sequence, the function returns an empty sequence.

Errors

Code Description
differing-length-arguments The arguments to a bitwise operation have different lengths.
index-out-of-range An offset value is out of range.
negative-size A size value is negative.
octet-out-of-range An octet value lies outside the range 0-255.
non-numeric-character Binary data cannot be parsed as number.
unknown-encoding An encoding is not supported.
conversion-error An error or malformed input during converting a string.
unknown-significance-order An octet-order value is unknown.

Changelog

Introduced with Version 7.8.