Index: wp-includes/class-json.php
===================================================================
--- wp-includes/class-json.php	(revision 0)
+++ wp-includes/class-json.php	(revision 0)
@@ -0,0 +1,861 @@
+<?php
+/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
+/**
+ * Converts to and from JSON format.
+ *
+ * JSON (JavaScript Object Notation) is a lightweight data-interchange
+ * format. It is easy for humans to read and write. It is easy for machines
+ * to parse and generate. It is based on a subset of the JavaScript
+ * Programming Language, Standard ECMA-262 3rd Edition - December 1999.
+ * This feature can also be found in  Python. JSON is a text format that is
+ * completely language independent but uses conventions that are familiar
+ * to programmers of the C-family of languages, including C, C++, C#, Java,
+ * JavaScript, Perl, TCL, and many others. These properties make JSON an
+ * ideal data-interchange language.
+ *
+ * This package provides a simple encoder and decoder for JSON notation. It
+ * is intended for use with client-side Javascript applications that make
+ * use of HTTPRequest to perform server communication functions - data can
+ * be encoded into JSON notation for use in a client-side javascript, or
+ * decoded from incoming Javascript requests. JSON format is native to
+ * Javascript, and can be directly eval()'ed with no further parsing
+ * overhead
+ *
+ * All strings should be in ASCII or UTF-8 format!
+ *
+ * LICENSE: Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met: Redistributions of source code must retain the
+ * above copyright notice, this list of conditions and the following
+ * disclaimer. Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+ * NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
+ * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+ * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * @category
+ * @package     Services_JSON
+ * @author      Michal Migurski <mike-json@teczno.com>
+ * @author      Matt Knapp <mdknapp[at]gmail[dot]com>
+ * @author      Brett Stimmerman <brettstimmerman[at]gmail[dot]com>
+ * @copyright   2005 Michal Migurski
+ * @version     CVS: $Id: JSON.php,v 1.3 2009/05/22 23:51:00 alan_k Exp $
+ * @license     http://www.opensource.org/licenses/bsd-license.php
+ * @link        http://pear.php.net/pepr/pepr-proposal-show.php?id=198
+ */
+
+/**
+ * Marker constant for Services_JSON::decode(), used to flag stack state
+ */
+define('SERVICES_JSON_SLICE',   1);
+
+/**
+ * Marker constant for Services_JSON::decode(), used to flag stack state
+ */
+define('SERVICES_JSON_IN_STR',  2);
+
+/**
+ * Marker constant for Services_JSON::decode(), used to flag stack state
+ */
+define('SERVICES_JSON_IN_ARR',  3);
+
+/**
+ * Marker constant for Services_JSON::decode(), used to flag stack state
+ */
+define('SERVICES_JSON_IN_OBJ',  4);
+
+/**
+ * Marker constant for Services_JSON::decode(), used to flag stack state
+ */
+define('SERVICES_JSON_IN_CMT', 5);
+
+/**
+ * Behavior switch for Services_JSON::decode()
+ */
+define('SERVICES_JSON_LOOSE_TYPE', 16);
+
+/**
+ * Behavior switch for Services_JSON::decode()
+ */
+define('SERVICES_JSON_SUPPRESS_ERRORS', 32);
+
+/**
+ * Converts to and from JSON format.
+ *
+ * Brief example of use:
+ *
+ * <code>
+ * // create a new instance of Services_JSON
+ * $json = new Services_JSON();
+ *
+ * // convert a complexe value to JSON notation, and send it to the browser
+ * $value = array('foo', 'bar', array(1, 2, 'baz'), array(3, array(4)));
+ * $output = $json->encode($value);
+ *
+ * print($output);
+ * // prints: ["foo","bar",[1,2,"baz"],[3,[4]]]
+ *
+ * // accept incoming POST data, assumed to be in JSON notation
+ * $input = file_get_contents('php://input', 1000000);
+ * $value = $json->decode($input);
+ * </code>
+ */
+class Services_JSON
+{
+   /**
+    * constructs a new JSON instance
+    *
+    * @param    int     $use    object behavior flags; combine with boolean-OR
+    *
+    *                           possible values:
+    *                           - SERVICES_JSON_LOOSE_TYPE:  loose typing.
+    *                                   "{...}" syntax creates associative arrays
+    *                                   instead of objects in decode().
+    *                           - SERVICES_JSON_SUPPRESS_ERRORS:  error suppression.
+    *                                   Values which can't be encoded (e.g. resources)
+    *                                   appear as NULL instead of throwing errors.
+    *                                   By default, a deeply-nested resource will
+    *                                   bubble up with an error, so all return values
+    *                                   from encode() should be checked with isError()
+    */
+    function Services_JSON($use = 0)
+    {
+        $this->use = $use;
+    }
+
+   /**
+    * convert a string from one UTF-16 char to one UTF-8 char
+    *
+    * Normally should be handled by mb_convert_encoding, but
+    * provides a slower PHP-only method for installations
+    * that lack the multibye string extension.
+    *
+    * @param    string  $utf16  UTF-16 character
+    * @return   string  UTF-8 character
+    * @access   private
+    */
+    function utf162utf8($utf16)
+    {
+        // oh please oh please oh please oh please oh please
+        if(function_exists('mb_convert_encoding')) {
+            return mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
+        }
+
+        $bytes = (ord($utf16{0}) << 8) | ord($utf16{1});
+
+        switch(true) {
+            case ((0x7F & $bytes) == $bytes):
+                // this case should never be reached, because we are in ASCII range
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return chr(0x7F & $bytes);
+
+            case (0x07FF & $bytes) == $bytes:
+                // return a 2-byte UTF-8 character
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return chr(0xC0 | (($bytes >> 6) & 0x1F))
+                     . chr(0x80 | ($bytes & 0x3F));
+
+            case (0xFFFF & $bytes) == $bytes:
+                // return a 3-byte UTF-8 character
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return chr(0xE0 | (($bytes >> 12) & 0x0F))
+                     . chr(0x80 | (($bytes >> 6) & 0x3F))
+                     . chr(0x80 | ($bytes & 0x3F));
+        }
+
+        // ignoring UTF-32 for now, sorry
+        return '';
+    }
+
+   /**
+    * convert a string from one UTF-8 char to one UTF-16 char
+    *
+    * Normally should be handled by mb_convert_encoding, but
+    * provides a slower PHP-only method for installations
+    * that lack the multibye string extension.
+    *
+    * @param    string  $utf8   UTF-8 character
+    * @return   string  UTF-16 character
+    * @access   private
+    */
+    function utf82utf16($utf8)
+    {
+        // oh please oh please oh please oh please oh please
+        if(function_exists('mb_convert_encoding')) {
+            return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
+        }
+
+        switch(strlen($utf8)) {
+            case 1:
+                // this case should never be reached, because we are in ASCII range
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return $utf8;
+
+            case 2:
+                // return a UTF-16 character from a 2-byte UTF-8 char
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return chr(0x07 & (ord($utf8{0}) >> 2))
+                     . chr((0xC0 & (ord($utf8{0}) << 6))
+                         | (0x3F & ord($utf8{1})));
+
+            case 3:
+                // return a UTF-16 character from a 3-byte UTF-8 char
+                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                return chr((0xF0 & (ord($utf8{0}) << 4))
+                         | (0x0F & (ord($utf8{1}) >> 2)))
+                     . chr((0xC0 & (ord($utf8{1}) << 6))
+                         | (0x7F & ord($utf8{2})));
+        }
+
+        // ignoring UTF-32 for now, sorry
+        return '';
+    }
+
+   /**
+    * encodes an arbitrary variable into JSON format (and sends JSON Header)
+    *
+    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
+    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
+    *                           if var is a strng, note that encode() always expects it
+    *                           to be in ASCII or UTF-8 format!
+    *
+    * @return   mixed   JSON string representation of input var or an error if a problem occurs
+    * @access   public
+    */
+    function encode($var)
+    {
+        header('Content-type: application/x-javascript');
+        return $this->_encode($var);
+    }
+    /**
+    * encodes an arbitrary variable into JSON format without JSON Header - warning - may allow CSS!!!!)
+    *
+    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
+    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
+    *                           if var is a strng, note that encode() always expects it
+    *                           to be in ASCII or UTF-8 format!
+    *
+    * @return   mixed   JSON string representation of input var or an error if a problem occurs
+    * @access   public
+    */
+    function encodeUnsafe($var)
+    {
+        return $this->_encode($var);
+    }
+    /**
+    * PRIVATE CODE that does the work of encodes an arbitrary variable into JSON format 
+    *
+    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
+    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
+    *                           if var is a strng, note that encode() always expects it
+    *                           to be in ASCII or UTF-8 format!
+    *
+    * @return   mixed   JSON string representation of input var or an error if a problem occurs
+    * @access   public
+    */
+    function _encode($var) 
+    {
+         
+        switch (gettype($var)) {
+            case 'boolean':
+                return $var ? 'true' : 'false';
+
+            case 'NULL':
+                return 'null';
+
+            case 'integer':
+                return (int) $var;
+
+            case 'double':
+            case 'float':
+                return (float) $var;
+
+            case 'string':
+                // STRINGS ARE EXPECTED TO BE IN ASCII OR UTF-8 FORMAT
+                $ascii = '';
+                $strlen_var = strlen($var);
+
+               /*
+                * Iterate over every character in the string,
+                * escaping with a slash or encoding to UTF-8 where necessary
+                */
+                for ($c = 0; $c < $strlen_var; ++$c) {
+
+                    $ord_var_c = ord($var{$c});
+
+                    switch (true) {
+                        case $ord_var_c == 0x08:
+                            $ascii .= '\b';
+                            break;
+                        case $ord_var_c == 0x09:
+                            $ascii .= '\t';
+                            break;
+                        case $ord_var_c == 0x0A:
+                            $ascii .= '\n';
+                            break;
+                        case $ord_var_c == 0x0C:
+                            $ascii .= '\f';
+                            break;
+                        case $ord_var_c == 0x0D:
+                            $ascii .= '\r';
+                            break;
+
+                        case $ord_var_c == 0x22:
+                        case $ord_var_c == 0x2F:
+                        case $ord_var_c == 0x5C:
+                            // double quote, slash, slosh
+                            $ascii .= '\\'.$var{$c};
+                            break;
+
+                        case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7F)):
+                            // characters U-00000000 - U-0000007F (same as ASCII)
+                            $ascii .= $var{$c};
+                            break;
+
+                        case (($ord_var_c & 0xE0) == 0xC0):
+                            // characters U-00000080 - U-000007FF, mask 110XXXXX
+                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                            if ($c+1 >= $strlen_var) {
+                                $c += 1;
+                                $ascii .= '?';
+                                break;
+                            }
+                            
+                            $char = pack('C*', $ord_var_c, ord($var{$c + 1}));
+                            $c += 1;
+                            $utf16 = $this->utf82utf16($char);
+                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
+                            break;
+
+                        case (($ord_var_c & 0xF0) == 0xE0):
+                            if ($c+2 >= $strlen_var) {
+                                $c += 2;
+                                $ascii .= '?';
+                                break;
+                            }
+                            // characters U-00000800 - U-0000FFFF, mask 1110XXXX
+                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                            $char = pack('C*', $ord_var_c,
+                                         @ord($var{$c + 1}),
+                                         @ord($var{$c + 2}));
+                            $c += 2;
+                            $utf16 = $this->utf82utf16($char);
+                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
+                            break;
+
+                        case (($ord_var_c & 0xF8) == 0xF0):
+                            if ($c+3 >= $strlen_var) {
+                                $c += 3;
+                                $ascii .= '?';
+                                break;
+                            }
+                            // characters U-00010000 - U-001FFFFF, mask 11110XXX
+                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                            $char = pack('C*', $ord_var_c,
+                                         ord($var{$c + 1}),
+                                         ord($var{$c + 2}),
+                                         ord($var{$c + 3}));
+                            $c += 3;
+                            $utf16 = $this->utf82utf16($char);
+                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
+                            break;
+
+                        case (($ord_var_c & 0xFC) == 0xF8):
+                            // characters U-00200000 - U-03FFFFFF, mask 111110XX
+                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                            if ($c+4 >= $strlen_var) {
+                                $c += 4;
+                                $ascii .= '?';
+                                break;
+                            }
+                            $char = pack('C*', $ord_var_c,
+                                         ord($var{$c + 1}),
+                                         ord($var{$c + 2}),
+                                         ord($var{$c + 3}),
+                                         ord($var{$c + 4}));
+                            $c += 4;
+                            $utf16 = $this->utf82utf16($char);
+                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
+                            break;
+
+                        case (($ord_var_c & 0xFE) == 0xFC):
+                        if ($c+5 >= $strlen_var) {
+                                $c += 5;
+                                $ascii .= '?';
+                                break;
+                            }
+                            // characters U-04000000 - U-7FFFFFFF, mask 1111110X
+                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                            $char = pack('C*', $ord_var_c,
+                                         ord($var{$c + 1}),
+                                         ord($var{$c + 2}),
+                                         ord($var{$c + 3}),
+                                         ord($var{$c + 4}),
+                                         ord($var{$c + 5}));
+                            $c += 5;
+                            $utf16 = $this->utf82utf16($char);
+                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
+                            break;
+                    }
+                }
+                return  '"'.$ascii.'"';
+
+            case 'array':
+               /*
+                * As per JSON spec if any array key is not an integer
+                * we must treat the the whole array as an object. We
+                * also try to catch a sparsely populated associative
+                * array with numeric keys here because some JS engines
+                * will create an array with empty indexes up to
+                * max_index which can cause memory issues and because
+                * the keys, which may be relevant, will be remapped
+                * otherwise.
+                *
+                * As per the ECMA and JSON specification an object may
+                * have any string as a property. Unfortunately due to
+                * a hole in the ECMA specification if the key is a
+                * ECMA reserved word or starts with a digit the
+                * parameter is only accessible using ECMAScript's
+                * bracket notation.
+                */
+
+                // treat as a JSON object
+                if (is_array($var) && count($var) && (array_keys($var) !== range(0, sizeof($var) - 1))) {
+                    $properties = array_map(array($this, 'name_value'),
+                                            array_keys($var),
+                                            array_values($var));
+
+                    foreach($properties as $property) {
+                        if(Services_JSON::isError($property)) {
+                            return $property;
+                        }
+                    }
+
+                    return '{' . join(',', $properties) . '}';
+                }
+
+                // treat it like a regular array
+                $elements = array_map(array($this, '_encode'), $var);
+
+                foreach($elements as $element) {
+                    if(Services_JSON::isError($element)) {
+                        return $element;
+                    }
+                }
+
+                return '[' . join(',', $elements) . ']';
+
+            case 'object':
+                $vars = get_object_vars($var);
+
+                $properties = array_map(array($this, 'name_value'),
+                                        array_keys($vars),
+                                        array_values($vars));
+
+                foreach($properties as $property) {
+                    if(Services_JSON::isError($property)) {
+                        return $property;
+                    }
+                }
+
+                return '{' . join(',', $properties) . '}';
+
+            default:
+                return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
+                    ? 'null'
+                    : new Services_JSON_Error(gettype($var)." can not be encoded as JSON string");
+        }
+    }
+
+   /**
+    * array-walking function for use in generating JSON-formatted name-value pairs
+    *
+    * @param    string  $name   name of key to use
+    * @param    mixed   $value  reference to an array element to be encoded
+    *
+    * @return   string  JSON-formatted name-value pair, like '"name":value'
+    * @access   private
+    */
+    function name_value($name, $value)
+    {
+        $encoded_value = $this->_encode($value);
+
+        if(Services_JSON::isError($encoded_value)) {
+            return $encoded_value;
+        }
+
+        return $this->_encode(strval($name)) . ':' . $encoded_value;
+    }
+
+   /**
+    * reduce a string by removing leading and trailing comments and whitespace
+    *
+    * @param    $str    string      string value to strip of comments and whitespace
+    *
+    * @return   string  string value stripped of comments and whitespace
+    * @access   private
+    */
+    function reduce_string($str)
+    {
+        $str = preg_replace(array(
+
+                // eliminate single line comments in '// ...' form
+                '#^\s*//(.+)$#m',
+
+                // eliminate multi-line comments in '/* ... */' form, at start of string
+                '#^\s*/\*(.+)\*/#Us',
+
+                // eliminate multi-line comments in '/* ... */' form, at end of string
+                '#/\*(.+)\*/\s*$#Us'
+
+            ), '', $str);
+
+        // eliminate extraneous space
+        return trim($str);
+    }
+
+   /**
+    * decodes a JSON string into appropriate variable
+    *
+    * @param    string  $str    JSON-formatted string
+    *
+    * @return   mixed   number, boolean, string, array, or object
+    *                   corresponding to given JSON input string.
+    *                   See argument 1 to Services_JSON() above for object-output behavior.
+    *                   Note that decode() always returns strings
+    *                   in ASCII or UTF-8 format!
+    * @access   public
+    */
+    function decode($str)
+    {
+        $str = $this->reduce_string($str);
+
+        switch (strtolower($str)) {
+            case 'true':
+                return true;
+
+            case 'false':
+                return false;
+
+            case 'null':
+                return null;
+
+            default:
+                $m = array();
+
+                if (is_numeric($str)) {
+                    // Lookie-loo, it's a number
+
+                    // This would work on its own, but I'm trying to be
+                    // good about returning integers where appropriate:
+                    // return (float)$str;
+
+                    // Return float or int, as appropriate
+                    return ((float)$str == (integer)$str)
+                        ? (integer)$str
+                        : (float)$str;
+
+                } elseif (preg_match('/^("|\').*(\1)$/s', $str, $m) && $m[1] == $m[2]) {
+                    // STRINGS RETURNED IN UTF-8 FORMAT
+                    $delim = substr($str, 0, 1);
+                    $chrs = substr($str, 1, -1);
+                    $utf8 = '';
+                    $strlen_chrs = strlen($chrs);
+
+                    for ($c = 0; $c < $strlen_chrs; ++$c) {
+
+                        $substr_chrs_c_2 = substr($chrs, $c, 2);
+                        $ord_chrs_c = ord($chrs{$c});
+
+                        switch (true) {
+                            case $substr_chrs_c_2 == '\b':
+                                $utf8 .= chr(0x08);
+                                ++$c;
+                                break;
+                            case $substr_chrs_c_2 == '\t':
+                                $utf8 .= chr(0x09);
+                                ++$c;
+                                break;
+                            case $substr_chrs_c_2 == '\n':
+                                $utf8 .= chr(0x0A);
+                                ++$c;
+                                break;
+                            case $substr_chrs_c_2 == '\f':
+                                $utf8 .= chr(0x0C);
+                                ++$c;
+                                break;
+                            case $substr_chrs_c_2 == '\r':
+                                $utf8 .= chr(0x0D);
+                                ++$c;
+                                break;
+
+                            case $substr_chrs_c_2 == '\\"':
+                            case $substr_chrs_c_2 == '\\\'':
+                            case $substr_chrs_c_2 == '\\\\':
+                            case $substr_chrs_c_2 == '\\/':
+                                if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
+                                   ($delim == "'" && $substr_chrs_c_2 != '\\"')) {
+                                    $utf8 .= $chrs{++$c};
+                                }
+                                break;
+
+                            case preg_match('/\\\u[0-9A-F]{4}/i', substr($chrs, $c, 6)):
+                                // single, escaped unicode character
+                                $utf16 = chr(hexdec(substr($chrs, ($c + 2), 2)))
+                                       . chr(hexdec(substr($chrs, ($c + 4), 2)));
+                                $utf8 .= $this->utf162utf8($utf16);
+                                $c += 5;
+                                break;
+
+                            case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F):
+                                $utf8 .= $chrs{$c};
+                                break;
+
+                            case ($ord_chrs_c & 0xE0) == 0xC0:
+                                // characters U-00000080 - U-000007FF, mask 110XXXXX
+                                //see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                                $utf8 .= substr($chrs, $c, 2);
+                                ++$c;
+                                break;
+
+                            case ($ord_chrs_c & 0xF0) == 0xE0:
+                                // characters U-00000800 - U-0000FFFF, mask 1110XXXX
+                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                                $utf8 .= substr($chrs, $c, 3);
+                                $c += 2;
+                                break;
+
+                            case ($ord_chrs_c & 0xF8) == 0xF0:
+                                // characters U-00010000 - U-001FFFFF, mask 11110XXX
+                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                                $utf8 .= substr($chrs, $c, 4);
+                                $c += 3;
+                                break;
+
+                            case ($ord_chrs_c & 0xFC) == 0xF8:
+                                // characters U-00200000 - U-03FFFFFF, mask 111110XX
+                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                                $utf8 .= substr($chrs, $c, 5);
+                                $c += 4;
+                                break;
+
+                            case ($ord_chrs_c & 0xFE) == 0xFC:
+                                // characters U-04000000 - U-7FFFFFFF, mask 1111110X
+                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
+                                $utf8 .= substr($chrs, $c, 6);
+                                $c += 5;
+                                break;
+
+                        }
+
+                    }
+
+                    return $utf8;
+
+                } elseif (preg_match('/^\[.*\]$/s', $str) || preg_match('/^\{.*\}$/s', $str)) {
+                    // array, or object notation
+
+                    if ($str{0} == '[') {
+                        $stk = array(SERVICES_JSON_IN_ARR);
+                        $arr = array();
+                    } else {
+                        if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
+                            $stk = array(SERVICES_JSON_IN_OBJ);
+                            $obj = array();
+                        } else {
+                            $stk = array(SERVICES_JSON_IN_OBJ);
+                            $obj = new stdClass();
+                        }
+                    }
+
+                    array_push($stk, array('what'  => SERVICES_JSON_SLICE,
+                                           'where' => 0,
+                                           'delim' => false));
+
+                    $chrs = substr($str, 1, -1);
+                    $chrs = $this->reduce_string($chrs);
+
+                    if ($chrs == '') {
+                        if (reset($stk) == SERVICES_JSON_IN_ARR) {
+                            return $arr;
+
+                        } else {
+                            return $obj;
+
+                        }
+                    }
+
+                    //print("\nparsing {$chrs}\n");
+
+                    $strlen_chrs = strlen($chrs);
+
+                    for ($c = 0; $c <= $strlen_chrs; ++$c) {
+
+                        $top = end($stk);
+                        $substr_chrs_c_2 = substr($chrs, $c, 2);
+
+                        if (($c == $strlen_chrs) || (($chrs{$c} == ',') && ($top['what'] == SERVICES_JSON_SLICE))) {
+                            // found a comma that is not inside a string, array, etc.,
+                            // OR we've reached the end of the character list
+                            $slice = substr($chrs, $top['where'], ($c - $top['where']));
+                            array_push($stk, array('what' => SERVICES_JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
+                            //print("Found split at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
+
+                            if (reset($stk) == SERVICES_JSON_IN_ARR) {
+                                // we are in an array, so just push an element onto the stack
+                                array_push($arr, $this->decode($slice));
+
+                            } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
+                                // we are in an object, so figure
+                                // out the property name and set an
+                                // element in an associative array,
+                                // for now
+                                $parts = array();
+                                
+                                if (preg_match('/^\s*(["\'].*[^\\\]["\'])\s*:\s*(\S.*),?$/Uis', $slice, $parts)) {
+                                    // "name":value pair
+                                    $key = $this->decode($parts[1]);
+                                    $val = $this->decode($parts[2]);
+
+                                    if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
+                                        $obj[$key] = $val;
+                                    } else {
+                                        $obj->$key = $val;
+                                    }
+                                } elseif (preg_match('/^\s*(\w+)\s*:\s*(\S.*),?$/Uis', $slice, $parts)) {
+                                    // name:value pair, where name is unquoted
+                                    $key = $parts[1];
+                                    $val = $this->decode($parts[2]);
+
+                                    if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
+                                        $obj[$key] = $val;
+                                    } else {
+                                        $obj->$key = $val;
+                                    }
+                                }
+
+                            }
+
+                        } elseif ((($chrs{$c} == '"') || ($chrs{$c} == "'")) && ($top['what'] != SERVICES_JSON_IN_STR)) {
+                            // found a quote, and we are not inside a string
+                            array_push($stk, array('what' => SERVICES_JSON_IN_STR, 'where' => $c, 'delim' => $chrs{$c}));
+                            //print("Found start of string at {$c}\n");
+
+                        } elseif (($chrs{$c} == $top['delim']) &&
+                                 ($top['what'] == SERVICES_JSON_IN_STR) &&
+                                 ((strlen(substr($chrs, 0, $c)) - strlen(rtrim(substr($chrs, 0, $c), '\\'))) % 2 != 1)) {
+                            // found a quote, we're in a string, and it's not escaped
+                            // we know that it's not escaped becase there is _not_ an
+                            // odd number of backslashes at the end of the string so far
+                            array_pop($stk);
+                            //print("Found end of string at {$c}: ".substr($chrs, $top['where'], (1 + 1 + $c - $top['where']))."\n");
+
+                        } elseif (($chrs{$c} == '[') &&
+                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
+                            // found a left-bracket, and we are in an array, object, or slice
+                            array_push($stk, array('what' => SERVICES_JSON_IN_ARR, 'where' => $c, 'delim' => false));
+                            //print("Found start of array at {$c}\n");
+
+                        } elseif (($chrs{$c} == ']') && ($top['what'] == SERVICES_JSON_IN_ARR)) {
+                            // found a right-bracket, and we're in an array
+                            array_pop($stk);
+                            //print("Found end of array at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
+
+                        } elseif (($chrs{$c} == '{') &&
+                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
+                            // found a left-brace, and we are in an array, object, or slice
+                            array_push($stk, array('what' => SERVICES_JSON_IN_OBJ, 'where' => $c, 'delim' => false));
+                            //print("Found start of object at {$c}\n");
+
+                        } elseif (($chrs{$c} == '}') && ($top['what'] == SERVICES_JSON_IN_OBJ)) {
+                            // found a right-brace, and we're in an object
+                            array_pop($stk);
+                            //print("Found end of object at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
+
+                        } elseif (($substr_chrs_c_2 == '/*') &&
+                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
+                            // found a comment start, and we are in an array, object, or slice
+                            array_push($stk, array('what' => SERVICES_JSON_IN_CMT, 'where' => $c, 'delim' => false));
+                            $c++;
+                            //print("Found start of comment at {$c}\n");
+
+                        } elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == SERVICES_JSON_IN_CMT)) {
+                            // found a comment end, and we're in one now
+                            array_pop($stk);
+                            $c++;
+
+                            for ($i = $top['where']; $i <= $c; ++$i)
+                                $chrs = substr_replace($chrs, ' ', $i, 1);
+
+                            //print("Found end of comment at {$c}: ".substr($chrs, $top['where'], (1 + $c - $top['where']))."\n");
+
+                        }
+
+                    }
+
+                    if (reset($stk) == SERVICES_JSON_IN_ARR) {
+                        return $arr;
+
+                    } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
+                        return $obj;
+
+                    }
+
+                }
+        }
+    }
+
+    /**
+     * @todo Ultimately, this should just call PEAR::isError()
+     */
+    function isError($data, $code = null)
+    {
+        if (class_exists('pear')) {
+            return PEAR::isError($data, $code);
+        } elseif (is_object($data) && (get_class($data) == 'services_json_error' ||
+                                 is_subclass_of($data, 'services_json_error'))) {
+            return true;
+        }
+
+        return false;
+    }
+}
+
+if (class_exists('PEAR_Error')) {
+
+    class Services_JSON_Error extends PEAR_Error
+    {
+        function Services_JSON_Error($message = 'unknown error', $code = null,
+                                     $mode = null, $options = null, $userinfo = null)
+        {
+            parent::PEAR_Error($message, $code, $mode, $options, $userinfo);
+        }
+    }
+
+} else {
+
+    /**
+     * @todo Ultimately, this class shall be descended from PEAR_Error
+     */
+    class Services_JSON_Error
+    {
+        function Services_JSON_Error($message = 'unknown error', $code = null,
+                                     $mode = null, $options = null, $userinfo = null)
+        {
+
+        }
+    }
+
+}
+   
Index: wp-includes/class-oembed.php
===================================================================
--- wp-includes/class-oembed.php	(revision 0)
+++ wp-includes/class-oembed.php	(revision 0)
@@ -0,0 +1,119 @@
+<?php
+
+class WP_oEmbed {
+	var $providers = array();
+
+	function WP_oEmbed() {
+		return $this->__construct();
+	}
+
+	function __construct() {
+		// List out some popular sites, mainly ones that don't have discovery tags in their <head>
+		// JSON URLs are preferred to XML
+		$this->providers = apply_filters( 'oembed_providers', array(
+			'http://www.hulu.com/watch/*' => 'http://www.hulu.com/api/oembed.{format}',
+			'http://*.viddler.com/*' => 'http://lab.viddler.com/services/oembed/',
+			//'http://*.youtube.com/watch*' => 'http://oohembed.com/oohembed/',
+		) );
+	}
+
+	// Pass a URL, returns false or HTML result
+	function getHTML( $url, $args = '' ) {
+		$provider = false;
+
+		foreach ( $this->providers as $scheme => $providerurl ) { // Needs a better variable name
+			$regex = '#' . str_replace( '___wildcard___', '(.+)', preg_quote( str_replace( '*', '___wildcard___', $scheme ) ) ) . '#i';
+
+			if ( preg_match( $regex, $url ) ) {
+				$provider = str_replace( '{format}', 'json', $providerurl ); // JSON is easier to deal with than XML
+				break;
+			}
+		}
+
+		if ( !$provider )
+			$provider = $this->discover( $url );
+
+		if ( !$provider )
+			return false;
+
+		return $this->fetch( $provider, $url, $args );
+	}
+
+	// Pass a URL, returns the oEmbed provider URL(s) if it can find them in the <head>
+	function discover( $url ) {
+		if ( !$html = wp_remote_retrieve_body( wp_remote_get( $url ) ) )
+			return false;
+
+		// <link> types that contain oEmbed provider URLs
+		$linktypes = apply_filters( 'oembed_linktypes', array(
+			'application/json+oembed' => 'json',
+			'text/xml+oembed' => 'xml',
+			'application/xml+oembed' => 'xml', // Incorrect, but used by at least Vimeo
+		) );
+
+		// Strip <body>
+		$html = substr( $html, 0, stripos( $html, '</head>' ) );
+
+		// Do a quick check
+		$tagfound = false;
+		foreach ( $linktypes as $linktype => $format ) {
+			if ( stripos($html, $linktype) ) {
+				$tagfound = true;
+				break;
+			}
+		}
+		if ( !$tagfound )
+			return false;
+
+		// Get all <link>'s
+		if ( !preg_match_all( '/<link([^<>]+)>/i', $html, $links ) )
+			return false;
+		
+		$provider = false;
+
+		foreach ( $links[1] as $link ) {
+			$atts = shortcode_parse_atts( $link );
+
+			if ( !empty($atts['type']) && !empty($linktypes[$atts['type']]) && !empty($atts['href']) ) {
+				// If it's JSON, we have all we need
+				if ( 'json' == $linktypes[$atts['type']] )
+					return $atts['href'];
+
+				// Otherwise hang onto it incase we can't find a JSON link
+				$provider = $atts['href'];
+			}
+		}
+
+		// This is either a XML URL or false
+		return $provider;
+	}
+
+	// Connects to an oEmbed provider and returns the HTML
+	function fetch( $provider, $url, $args = '' ) {
+		$args = wp_parse_args( $args, wp_embed_defaults() );
+
+		$provider = add_query_arg( 'format', 'json', $provider ); // JSON is easier to deal with than XML
+
+		$provider = add_query_arg( 'maxwidth', $args['width'], $provider );
+		$provider = add_query_arg( 'maxheight', $args['height'], $provider );
+		$provider = add_query_arg( 'url', urlencode($url), $provider );
+
+		$result = wp_remote_retrieve_body( wp_remote_get( $provider ) );
+
+		if ( empty($result) || !$result = json_decode($result) ) // No XML support yet
+			return false;
+
+		// TODO: Add a ton of security here
+
+		return ( !empty($result->html) ) ? $result->html : false;
+	}
+}
+
+function &_wp_oembed_get_object() {
+	static $oembed;
+
+	if ( is_null($oembed) )
+		$oembed = new WP_oEmbed();
+
+	return $oembed;
+}
Index: wp-includes/compat.php
===================================================================
--- wp-includes/compat.php	(revision 11809)
+++ wp-includes/compat.php	(working copy)
@@ -56,7 +56,7 @@
 	}
 }
 
-if ( ! function_exists('hash_hmac') ):
+if ( !function_exists('hash_hmac') ):
 function hash_hmac($algo, $data, $key, $raw_output = false) {
 	$packs = array('md5' => 'H32', 'sha1' => 'H40');
 
@@ -77,7 +77,7 @@
 }
 endif;
 
-if ( ! function_exists('mb_substr') ):
+if ( !function_exists('mb_substr') ):
 	function mb_substr( $str, $start, $length=null, $encoding=null ) {
 		return _mb_substr($str, $start, $length, $encoding);
 	}
@@ -115,4 +115,22 @@
 	}
 }
 
-?>
+if ( !function_exists('json_encode') ) {
+	function json_encode( $string ) {
+		require_once( 'class-json.php' );
+
+		$json = new Services_JSON();
+
+		return $json->encode( $string );
+	}
+}
+
+if ( !function_exists('json_decode') ) {
+	function json_decode( $string ) {
+		require_once( 'class-json.php' );
+
+		$json = new Services_JSON();
+
+		return $json->decode( $string );
+	}
+}
Index: wp-includes/media.php
===================================================================
--- wp-includes/media.php	(revision 11809)
+++ wp-includes/media.php	(working copy)
@@ -933,3 +933,80 @@
 
 	return false;
 }
+
+
+
+
+
+
+
+
+
+// Embed class
+class WP_Embed {
+	var $handlers = array();
+
+	function register_handler( $id, $regex, $callback, $priority = 10 ) {
+		$this->handlers[$priority][$id] = array(
+			'regex'    => $regex,
+			'callback' => $callback,
+		);
+	}
+
+	function shortcode( $atts, $url = '' ) {
+		$atts = wp_parse_args( $atts, wp_embed_defaults() );
+
+		// Look for known internal handlers
+		ksort( $this->handlers );
+		foreach ( $this->handlers as $handlers ) {
+			foreach ( $handlers as $id => $handler ) {
+				if ( preg_match( $handler['regex'], $url, $matches ) && is_callable( $handler['callback'] ) ) {
+					return call_user_func( $handler['callback'], $matches, $atts, $url );
+				}
+			}
+		}
+
+		// Unknown URL format. Let oEmbed have a go.
+		if ( current_user_can('unfiltered_html') && $html = wp_oembed_get( $url, $atts ) )
+			return $html;
+
+		// Still unknown, so just output a link
+		return '<a href="' . esc_attr($url) . '">' . esc_html($url) . '</a>';
+	}
+}
+
+$wp_embed = new WP_Embed();
+
+// Register [embed] shortcode, handled by WP_Embed class
+add_shortcode( 'embed', array(&$wp_embed, 'shortcode') );
+
+// Wrapper to register a new hander for a URL format inside [embed]
+function wp_embed_register_handler( $id, $regex, $callback ) {
+	global $wp_embed;
+	return $wp_embed->register_handler( $id, $regex, $callback );
+}
+
+// YouTube doesn't support oEmbed, so handle it interanlly
+wp_embed_register_handler( 'youtube', '#http://(www.youtube|youtube|[A-Za-z]{2}.youtube)\.com/(watch\?v=|w/\?v=|\?v=)([\w-]+)(.*?)#i', 'wp_embed_handler_youtube' );
+function wp_embed_handler_youtube( $matches, $atts, $url ) {
+	list($width, $height) = wp_embed_calcdims( 425, 344, $atts['width'], $atts['height'] );
+	return "<object width='$width' height='$height'><param name='movie' value='http://www.youtube.com/v/{$matches[3]}&amp;hl=en&amp;fs=1'></param><param name='allowFullScreen' value='true'></param><param name='allowscriptaccess' value='always'></param><embed src='http://www.youtube.com/v/{$matches[3]}&amp;hl=en&amp;fs=1' type='application/x-shockwave-flash' allowscriptaccess='always' allowfullscreen='true' width='$width' height='$height'></embed></object>";
+}
+
+function wp_embed_defaults() {
+	return apply_filters( 'embed_defaults', array(
+		'width' => 500,
+		'height' => 700,
+	) );
+}
+
+function wp_embed_calcdims( $example_width, $example_height, $max_width, $max_height ) {
+	return wp_constrain_dimensions( $example_width * 1000000, $example_height * 1000000, $max_width, $max_height );
+}
+
+// Wrapper to load oEmbed class and use it to get some HTML
+function wp_oembed_get( $url, $args = '' ) {
+	require_once( 'class-oembed.php' );
+	$oembed_object = _wp_oembed_get_object();
+	return $oembed_object->getHTML( $url, $args );
+}
\ No newline at end of file
