1<?php
2/* vim: set expandtab tabstop=4 shiftwidth=4 softtabstop=4: */
3/**
4 * Converts to and from JSON format.
5 *
6 * JSON (JavaScript Object Notation) is a lightweight data-interchange
7 * format. It is easy for humans to read and write. It is easy for machines
8 * to parse and generate. It is based on a subset of the JavaScript
9 * Programming Language, Standard ECMA-262 3rd Edition - December 1999.
10 * This feature can also be found in  Python. JSON is a text format that is
11 * completely language independent but uses conventions that are familiar
12 * to programmers of the C-family of languages, including C, C++, C#, Java,
13 * JavaScript, Perl, TCL, and many others. These properties make JSON an
14 * ideal data-interchange language.
15 *
16 * This package provides a simple encoder and decoder for JSON notation. It
17 * is intended for use with client-side Javascript applications that make
18 * use of HTTPRequest to perform server communication functions - data can
19 * be encoded into JSON notation for use in a client-side javascript, or
20 * decoded from incoming Javascript requests. JSON format is native to
21 * Javascript, and can be directly eval()'ed with no further parsing
22 * overhead
23 *
24 * All strings should be in ASCII or UTF-8 format!
25 *
26 * LICENSE: Redistribution and use in source and binary forms, with or
27 * without modification, are permitted provided that the following
28 * conditions are met: Redistributions of source code must retain the
29 * above copyright notice, this list of conditions and the following
30 * disclaimer. Redistributions in binary form must reproduce the above
31 * copyright notice, this list of conditions and the following disclaimer
32 * in the documentation and/or other materials provided with the
33 * distribution.
34 *
35 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
36 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
37 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
38 * NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
39 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
40 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
41 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
42 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
43 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
44 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
45 * DAMAGE.
46 *
47 * @category
48 * @package     Services_JSON
49 * @author      Michal Migurski <mike-json@teczno.com>
50 * @author      Matt Knapp <mdknapp[at]gmail[dot]com>
51 * @author      Brett Stimmerman <brettstimmerman[at]gmail[dot]com>
52 * @copyright   2005 Michal Migurski
53 * @version     CVS: $Id: JSON.php 305040 2010-11-02 23:19:03Z alan_k $
54 * @license     http://www.opensource.org/licenses/bsd-license.php
55 * @link        http://pear.php.net/pepr/pepr-proposal-show.php?id=198
56 */
57
58/**
59 * Marker constant for Services_JSON::decode(), used to flag stack state
60 */
61define('SERVICES_JSON_SLICE',   1);
62
63/**
64 * Marker constant for Services_JSON::decode(), used to flag stack state
65 */
66define('SERVICES_JSON_IN_STR',  2);
67
68/**
69 * Marker constant for Services_JSON::decode(), used to flag stack state
70 */
71define('SERVICES_JSON_IN_ARR',  3);
72
73/**
74 * Marker constant for Services_JSON::decode(), used to flag stack state
75 */
76define('SERVICES_JSON_IN_OBJ',  4);
77
78/**
79 * Marker constant for Services_JSON::decode(), used to flag stack state
80 */
81define('SERVICES_JSON_IN_CMT', 5);
82
83/**
84 * Behavior switch for Services_JSON::decode()
85 */
86define('SERVICES_JSON_LOOSE_TYPE', 16);
87
88/**
89 * Behavior switch for Services_JSON::decode()
90 */
91define('SERVICES_JSON_SUPPRESS_ERRORS', 32);
92
93/**
94 * Behavior switch for Services_JSON::decode()
95 */
96define('SERVICES_JSON_USE_TO_JSON', 64);
97
98/**
99 * Converts to and from JSON format.
100 *
101 * Brief example of use:
102 *
103 * <code>
104 * // create a new instance of Services_JSON
105 * $json = new Services_JSON();
106 *
107 * // convert a complexe value to JSON notation, and send it to the browser
108 * $value = array('foo', 'bar', array(1, 2, 'baz'), array(3, array(4)));
109 * $output = $json->encode($value);
110 *
111 * print($output);
112 * // prints: ["foo","bar",[1,2,"baz"],[3,[4]]]
113 *
114 * // accept incoming POST data, assumed to be in JSON notation
115 * $input = file_get_contents('php://input', 1000000);
116 * $value = $json->decode($input);
117 * </code>
118 */
119class Services_JSON
120{
121   /**
122    * constructs a new JSON instance
123    *
124    * @param    int     $use    object behavior flags; combine with boolean-OR
125    *
126    *                           possible values:
127    *                           - SERVICES_JSON_LOOSE_TYPE:  loose typing.
128    *                                   "{...}" syntax creates associative arrays
129    *                                   instead of objects in decode().
130    *                           - SERVICES_JSON_SUPPRESS_ERRORS:  error suppression.
131    *                                   Values which can't be encoded (e.g. resources)
132    *                                   appear as NULL instead of throwing errors.
133    *                                   By default, a deeply-nested resource will
134    *                                   bubble up with an error, so all return values
135    *                                   from encode() should be checked with isError()
136    *                           - SERVICES_JSON_USE_TO_JSON:  call toJSON when serializing objects
137    *                                   It serializes the return value from the toJSON call rather
138    *                                   than the object it'self,  toJSON can return associative arrays,
139    *                                   strings or numbers, if you return an object, make sure it does
140    *                                   not have a toJSON method, otherwise an error will occur.
141    */
142    function Services_JSON($use = 0)
143    {
144        $this->use = $use;
145        $this->_mb_strlen            = function_exists('mb_strlen');
146        $this->_mb_convert_encoding  = function_exists('mb_convert_encoding');
147        $this->_mb_substr            = function_exists('mb_substr');
148    }
149    // private - cache the mbstring lookup results..
150    var $_mb_strlen = false;
151    var $_mb_substr = false;
152    var $_mb_convert_encoding = false;
153
154   /**
155    * convert a string from one UTF-16 char to one UTF-8 char
156    *
157    * Normally should be handled by mb_convert_encoding, but
158    * provides a slower PHP-only method for installations
159    * that lack the multibye string extension.
160    *
161    * @param    string  $utf16  UTF-16 character
162    * @return   string  UTF-8 character
163    * @access   private
164    */
165    function utf162utf8($utf16)
166    {
167        // oh please oh please oh please oh please oh please
168        if($this->_mb_convert_encoding) {
169            return mb_convert_encoding($utf16, 'UTF-8', 'UTF-16');
170        }
171
172        $bytes = (ord($utf16{0}) << 8) | ord($utf16{1});
173
174        switch(true) {
175            case ((0x7F & $bytes) == $bytes):
176                // this case should never be reached, because we are in ASCII range
177                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
178                return chr(0x7F & $bytes);
179
180            case (0x07FF & $bytes) == $bytes:
181                // return a 2-byte UTF-8 character
182                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
183                return chr(0xC0 | (($bytes >> 6) & 0x1F))
184                     . chr(0x80 | ($bytes & 0x3F));
185
186            case (0xFFFF & $bytes) == $bytes:
187                // return a 3-byte UTF-8 character
188                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
189                return chr(0xE0 | (($bytes >> 12) & 0x0F))
190                     . chr(0x80 | (($bytes >> 6) & 0x3F))
191                     . chr(0x80 | ($bytes & 0x3F));
192        }
193
194        // ignoring UTF-32 for now, sorry
195        return '';
196    }
197
198   /**
199    * convert a string from one UTF-8 char to one UTF-16 char
200    *
201    * Normally should be handled by mb_convert_encoding, but
202    * provides a slower PHP-only method for installations
203    * that lack the multibye string extension.
204    *
205    * @param    string  $utf8   UTF-8 character
206    * @return   string  UTF-16 character
207    * @access   private
208    */
209    function utf82utf16($utf8)
210    {
211        // oh please oh please oh please oh please oh please
212        if($this->_mb_convert_encoding) {
213            return mb_convert_encoding($utf8, 'UTF-16', 'UTF-8');
214        }
215
216        switch($this->strlen8($utf8)) {
217            case 1:
218                // this case should never be reached, because we are in ASCII range
219                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
220                return $utf8;
221
222            case 2:
223                // return a UTF-16 character from a 2-byte UTF-8 char
224                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
225                return chr(0x07 & (ord($utf8{0}) >> 2))
226                     . chr((0xC0 & (ord($utf8{0}) << 6))
227                         | (0x3F & ord($utf8{1})));
228
229            case 3:
230                // return a UTF-16 character from a 3-byte UTF-8 char
231                // see: http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
232                return chr((0xF0 & (ord($utf8{0}) << 4))
233                         | (0x0F & (ord($utf8{1}) >> 2)))
234                     . chr((0xC0 & (ord($utf8{1}) << 6))
235                         | (0x7F & ord($utf8{2})));
236        }
237
238        // ignoring UTF-32 for now, sorry
239        return '';
240    }
241
242   /**
243    * encodes an arbitrary variable into JSON format (and sends JSON Header)
244    *
245    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
246    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
247    *                           if var is a strng, note that encode() always expects it
248    *                           to be in ASCII or UTF-8 format!
249    *
250    * @return   mixed   JSON string representation of input var or an error if a problem occurs
251    * @access   public
252    */
253    function encode($var)
254    {
255        header('Content-type: application/json');
256        return $this->encodeUnsafe($var);
257    }
258    /**
259    * encodes an arbitrary variable into JSON format without JSON Header - warning - may allow XSS!!!!)
260    *
261    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
262    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
263    *                           if var is a strng, note that encode() always expects it
264    *                           to be in ASCII or UTF-8 format!
265    *
266    * @return   mixed   JSON string representation of input var or an error if a problem occurs
267    * @access   public
268    */
269    function encodeUnsafe($var)
270    {
271        // see bug #16908 - regarding numeric locale printing
272        $lc = setlocale(LC_NUMERIC, 0);
273        setlocale(LC_NUMERIC, 'C');
274        $ret = $this->_encode($var);
275        setlocale(LC_NUMERIC, $lc);
276        return $ret;
277
278    }
279    /**
280    * PRIVATE CODE that does the work of encodes an arbitrary variable into JSON format
281    *
282    * @param    mixed   $var    any number, boolean, string, array, or object to be encoded.
283    *                           see argument 1 to Services_JSON() above for array-parsing behavior.
284    *                           if var is a strng, note that encode() always expects it
285    *                           to be in ASCII or UTF-8 format!
286    *
287    * @return   mixed   JSON string representation of input var or an error if a problem occurs
288    * @access   public
289    */
290    function _encode($var)
291    {
292
293        switch (gettype($var)) {
294            case 'boolean':
295                return $var ? 'true' : 'false';
296
297            case 'NULL':
298                return 'null';
299
300            case 'integer':
301                return (int) $var;
302
303            case 'double':
304            case 'float':
305                return  (float) $var;
306
307            case 'string':
308                // STRINGS ARE EXPECTED TO BE IN ASCII OR UTF-8 FORMAT
309                $ascii = '';
310                $strlen_var = $this->strlen8($var);
311
312               /*
313                * Iterate over every character in the string,
314                * escaping with a slash or encoding to UTF-8 where necessary
315                */
316                for ($c = 0; $c < $strlen_var; ++$c) {
317
318                    $ord_var_c = ord($var{$c});
319
320                    switch (true) {
321                        case $ord_var_c == 0x08:
322                            $ascii .= '\b';
323                            break;
324                        case $ord_var_c == 0x09:
325                            $ascii .= '\t';
326                            break;
327                        case $ord_var_c == 0x0A:
328                            $ascii .= '\n';
329                            break;
330                        case $ord_var_c == 0x0C:
331                            $ascii .= '\f';
332                            break;
333                        case $ord_var_c == 0x0D:
334                            $ascii .= '\r';
335                            break;
336
337                        case $ord_var_c == 0x22:
338                        case $ord_var_c == 0x2F:
339                        case $ord_var_c == 0x5C:
340                            // double quote, slash, slosh
341                            $ascii .= '\\'.$var{$c};
342                            break;
343
344                        case (($ord_var_c >= 0x20) && ($ord_var_c <= 0x7F)):
345                            // characters U-00000000 - U-0000007F (same as ASCII)
346                            $ascii .= $var{$c};
347                            break;
348
349                        case (($ord_var_c & 0xE0) == 0xC0):
350                            // characters U-00000080 - U-000007FF, mask 110XXXXX
351                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
352                            if ($c+1 >= $strlen_var) {
353                                $c += 1;
354                                $ascii .= '?';
355                                break;
356                            }
357
358                            $char = pack('C*', $ord_var_c, ord($var{$c + 1}));
359                            $c += 1;
360                            $utf16 = $this->utf82utf16($char);
361                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
362                            break;
363
364                        case (($ord_var_c & 0xF0) == 0xE0):
365                            if ($c+2 >= $strlen_var) {
366                                $c += 2;
367                                $ascii .= '?';
368                                break;
369                            }
370                            // characters U-00000800 - U-0000FFFF, mask 1110XXXX
371                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
372                            $char = pack('C*', $ord_var_c,
373                                         @ord($var{$c + 1}),
374                                         @ord($var{$c + 2}));
375                            $c += 2;
376                            $utf16 = $this->utf82utf16($char);
377                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
378                            break;
379
380                        case (($ord_var_c & 0xF8) == 0xF0):
381                            if ($c+3 >= $strlen_var) {
382                                $c += 3;
383                                $ascii .= '?';
384                                break;
385                            }
386                            // characters U-00010000 - U-001FFFFF, mask 11110XXX
387                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
388                            $char = pack('C*', $ord_var_c,
389                                         ord($var{$c + 1}),
390                                         ord($var{$c + 2}),
391                                         ord($var{$c + 3}));
392                            $c += 3;
393                            $utf16 = $this->utf82utf16($char);
394                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
395                            break;
396
397                        case (($ord_var_c & 0xFC) == 0xF8):
398                            // characters U-00200000 - U-03FFFFFF, mask 111110XX
399                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
400                            if ($c+4 >= $strlen_var) {
401                                $c += 4;
402                                $ascii .= '?';
403                                break;
404                            }
405                            $char = pack('C*', $ord_var_c,
406                                         ord($var{$c + 1}),
407                                         ord($var{$c + 2}),
408                                         ord($var{$c + 3}),
409                                         ord($var{$c + 4}));
410                            $c += 4;
411                            $utf16 = $this->utf82utf16($char);
412                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
413                            break;
414
415                        case (($ord_var_c & 0xFE) == 0xFC):
416                        if ($c+5 >= $strlen_var) {
417                                $c += 5;
418                                $ascii .= '?';
419                                break;
420                            }
421                            // characters U-04000000 - U-7FFFFFFF, mask 1111110X
422                            // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
423                            $char = pack('C*', $ord_var_c,
424                                         ord($var{$c + 1}),
425                                         ord($var{$c + 2}),
426                                         ord($var{$c + 3}),
427                                         ord($var{$c + 4}),
428                                         ord($var{$c + 5}));
429                            $c += 5;
430                            $utf16 = $this->utf82utf16($char);
431                            $ascii .= sprintf('\u%04s', bin2hex($utf16));
432                            break;
433                    }
434                }
435                return  '"'.$ascii.'"';
436
437            case 'array':
438               /*
439                * As per JSON spec if any array key is not an integer
440                * we must treat the the whole array as an object. We
441                * also try to catch a sparsely populated associative
442                * array with numeric keys here because some JS engines
443                * will create an array with empty indexes up to
444                * max_index which can cause memory issues and because
445                * the keys, which may be relevant, will be remapped
446                * otherwise.
447                *
448                * As per the ECMA and JSON specification an object may
449                * have any string as a property. Unfortunately due to
450                * a hole in the ECMA specification if the key is a
451                * ECMA reserved word or starts with a digit the
452                * parameter is only accessible using ECMAScript's
453                * bracket notation.
454                */
455
456                // treat as a JSON object
457                if (is_array($var) && count($var) && (array_keys($var) !== range(0, count($var) - 1))) {
458                    $properties = array_map(array($this, 'name_value'),
459                                            array_keys($var),
460                                            array_values($var));
461
462                    foreach($properties as $property) {
463                        if(Services_JSON::isError($property)) {
464                            return $property;
465                        }
466                    }
467
468                    return '{' . join(',', $properties) . '}';
469                }
470
471                // treat it like a regular array
472                $elements = array_map(array($this, '_encode'), $var);
473
474                foreach($elements as $element) {
475                    if(Services_JSON::isError($element)) {
476                        return $element;
477                    }
478                }
479
480                return '[' . join(',', $elements) . ']';
481
482            case 'object':
483
484                // support toJSON methods.
485                if (($this->use & SERVICES_JSON_USE_TO_JSON) && method_exists($var, 'toJSON')) {
486                    // this may end up allowing unlimited recursion
487                    // so we check the return value to make sure it's not got the same method.
488                    $recode = $var->toJSON();
489
490                    if (method_exists($recode, 'toJSON')) {
491
492                        return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
493                        ? 'null'
494                        : new Services_JSON_Error(class_name($var).
495                            " toJSON returned an object with a toJSON method.");
496
497                    }
498
499                    return $this->_encode( $recode );
500                }
501
502                $vars = get_object_vars($var);
503
504                $properties = array_map(array($this, 'name_value'),
505                                        array_keys($vars),
506                                        array_values($vars));
507
508                foreach($properties as $property) {
509                    if(Services_JSON::isError($property)) {
510                        return $property;
511                    }
512                }
513
514                return '{' . join(',', $properties) . '}';
515
516            default:
517                return ($this->use & SERVICES_JSON_SUPPRESS_ERRORS)
518                    ? 'null'
519                    : new Services_JSON_Error(gettype($var)." can not be encoded as JSON string");
520        }
521    }
522
523   /**
524    * array-walking function for use in generating JSON-formatted name-value pairs
525    *
526    * @param    string  $name   name of key to use
527    * @param    mixed   $value  reference to an array element to be encoded
528    *
529    * @return   string  JSON-formatted name-value pair, like '"name":value'
530    * @access   private
531    */
532    function name_value($name, $value)
533    {
534        $encoded_value = $this->_encode($value);
535
536        if(Services_JSON::isError($encoded_value)) {
537            return $encoded_value;
538        }
539
540        return $this->_encode(strval($name)) . ':' . $encoded_value;
541    }
542
543   /**
544    * reduce a string by removing leading and trailing comments and whitespace
545    *
546    * @param    $str    string      string value to strip of comments and whitespace
547    *
548    * @return   string  string value stripped of comments and whitespace
549    * @access   private
550    */
551    function reduce_string($str)
552    {
553        $str = preg_replace(array(
554
555                // eliminate single line comments in '// ...' form
556                '#^\s*//(.+)$#m',
557
558                // eliminate multi-line comments in '/* ... */' form, at start of string
559                '#^\s*/\*(.+)\*/#Us',
560
561                // eliminate multi-line comments in '/* ... */' form, at end of string
562                '#/\*(.+)\*/\s*$#Us'
563
564            ), '', $str);
565
566        // eliminate extraneous space
567        return trim($str);
568    }
569
570   /**
571    * decodes a JSON string into appropriate variable
572    *
573    * @param    string  $str    JSON-formatted string
574    *
575    * @return   mixed   number, boolean, string, array, or object
576    *                   corresponding to given JSON input string.
577    *                   See argument 1 to Services_JSON() above for object-output behavior.
578    *                   Note that decode() always returns strings
579    *                   in ASCII or UTF-8 format!
580    * @access   public
581    */
582    function decode($str)
583    {
584        $str = $this->reduce_string($str);
585
586        switch (strtolower($str)) {
587            case 'true':
588                return true;
589
590            case 'false':
591                return false;
592
593            case 'null':
594                return null;
595
596            default:
597                $m = array();
598
599                if (is_numeric($str)) {
600                    // Lookie-loo, it's a number
601
602                    // This would work on its own, but I'm trying to be
603                    // good about returning integers where appropriate:
604                    // return (float)$str;
605
606                    // Return float or int, as appropriate
607                    return ((float)$str == (integer)$str)
608                        ? (integer)$str
609                        : (float)$str;
610
611                } elseif (preg_match('/^("|\').*(\1)$/s', $str, $m) && $m[1] == $m[2]) {
612                    // STRINGS RETURNED IN UTF-8 FORMAT
613                    $delim = $this->substr8($str, 0, 1);
614                    $chrs = $this->substr8($str, 1, -1);
615                    $utf8 = '';
616                    $strlen_chrs = $this->strlen8($chrs);
617
618                    for ($c = 0; $c < $strlen_chrs; ++$c) {
619
620                        $substr_chrs_c_2 = $this->substr8($chrs, $c, 2);
621                        $ord_chrs_c = ord($chrs{$c});
622
623                        switch (true) {
624                            case $substr_chrs_c_2 == '\b':
625                                $utf8 .= chr(0x08);
626                                ++$c;
627                                break;
628                            case $substr_chrs_c_2 == '\t':
629                                $utf8 .= chr(0x09);
630                                ++$c;
631                                break;
632                            case $substr_chrs_c_2 == '\n':
633                                $utf8 .= chr(0x0A);
634                                ++$c;
635                                break;
636                            case $substr_chrs_c_2 == '\f':
637                                $utf8 .= chr(0x0C);
638                                ++$c;
639                                break;
640                            case $substr_chrs_c_2 == '\r':
641                                $utf8 .= chr(0x0D);
642                                ++$c;
643                                break;
644
645                            case $substr_chrs_c_2 == '\\"':
646                            case $substr_chrs_c_2 == '\\\'':
647                            case $substr_chrs_c_2 == '\\\\':
648                            case $substr_chrs_c_2 == '\\/':
649                                if (($delim == '"' && $substr_chrs_c_2 != '\\\'') ||
650                                   ($delim == "'" && $substr_chrs_c_2 != '\\"')) {
651                                    $utf8 .= $chrs{++$c};
652                                }
653                                break;
654
655                            case preg_match('/\\\u[0-9A-F]{4}/i', $this->substr8($chrs, $c, 6)):
656                                // single, escaped unicode character
657                                $utf16 = chr(hexdec($this->substr8($chrs, ($c + 2), 2)))
658                                       . chr(hexdec($this->substr8($chrs, ($c + 4), 2)));
659                                $utf8 .= $this->utf162utf8($utf16);
660                                $c += 5;
661                                break;
662
663                            case ($ord_chrs_c >= 0x20) && ($ord_chrs_c <= 0x7F):
664                                $utf8 .= $chrs{$c};
665                                break;
666
667                            case ($ord_chrs_c & 0xE0) == 0xC0:
668                                // characters U-00000080 - U-000007FF, mask 110XXXXX
669                                //see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
670                                $utf8 .= $this->substr8($chrs, $c, 2);
671                                ++$c;
672                                break;
673
674                            case ($ord_chrs_c & 0xF0) == 0xE0:
675                                // characters U-00000800 - U-0000FFFF, mask 1110XXXX
676                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
677                                $utf8 .= $this->substr8($chrs, $c, 3);
678                                $c += 2;
679                                break;
680
681                            case ($ord_chrs_c & 0xF8) == 0xF0:
682                                // characters U-00010000 - U-001FFFFF, mask 11110XXX
683                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
684                                $utf8 .= $this->substr8($chrs, $c, 4);
685                                $c += 3;
686                                break;
687
688                            case ($ord_chrs_c & 0xFC) == 0xF8:
689                                // characters U-00200000 - U-03FFFFFF, mask 111110XX
690                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
691                                $utf8 .= $this->substr8($chrs, $c, 5);
692                                $c += 4;
693                                break;
694
695                            case ($ord_chrs_c & 0xFE) == 0xFC:
696                                // characters U-04000000 - U-7FFFFFFF, mask 1111110X
697                                // see http://www.cl.cam.ac.uk/~mgk25/unicode.html#utf-8
698                                $utf8 .= $this->substr8($chrs, $c, 6);
699                                $c += 5;
700                                break;
701
702                        }
703
704                    }
705
706                    return $utf8;
707
708                } elseif (preg_match('/^\[.*\]$/s', $str) || preg_match('/^\{.*\}$/s', $str)) {
709                    // array, or object notation
710
711                    if ($str{0} == '[') {
712                        $stk = array(SERVICES_JSON_IN_ARR);
713                        $arr = array();
714                    } else {
715                        if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
716                            $stk = array(SERVICES_JSON_IN_OBJ);
717                            $obj = array();
718                        } else {
719                            $stk = array(SERVICES_JSON_IN_OBJ);
720                            $obj = new stdClass();
721                        }
722                    }
723
724                    array_push($stk, array('what'  => SERVICES_JSON_SLICE,
725                                           'where' => 0,
726                                           'delim' => false));
727
728                    $chrs = $this->substr8($str, 1, -1);
729                    $chrs = $this->reduce_string($chrs);
730
731                    if ($chrs == '') {
732                        if (reset($stk) == SERVICES_JSON_IN_ARR) {
733                            return $arr;
734
735                        } else {
736                            return $obj;
737
738                        }
739                    }
740
741                    //print("\nparsing {$chrs}\n");
742
743                    $strlen_chrs = $this->strlen8($chrs);
744
745                    for ($c = 0; $c <= $strlen_chrs; ++$c) {
746
747                        $top = end($stk);
748                        $substr_chrs_c_2 = $this->substr8($chrs, $c, 2);
749
750                        if (($c == $strlen_chrs) || (($chrs{$c} == ',') && ($top['what'] == SERVICES_JSON_SLICE))) {
751                            // found a comma that is not inside a string, array, etc.,
752                            // OR we've reached the end of the character list
753                            $slice = $this->substr8($chrs, $top['where'], ($c - $top['where']));
754                            array_push($stk, array('what' => SERVICES_JSON_SLICE, 'where' => ($c + 1), 'delim' => false));
755                            //print("Found split at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");
756
757                            if (reset($stk) == SERVICES_JSON_IN_ARR) {
758                                // we are in an array, so just push an element onto the stack
759                                array_push($arr, $this->decode($slice));
760
761                            } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
762                                // we are in an object, so figure
763                                // out the property name and set an
764                                // element in an associative array,
765                                // for now
766                                $parts = array();
767
768                               if (preg_match('/^\s*(["\'].*[^\\\]["\'])\s*:/Uis', $slice, $parts)) {
769 	                              // "name":value pair
770                                    $key = $this->decode($parts[1]);
771                                    $val = $this->decode(trim(substr($slice, strlen($parts[0])), ", \t\n\r\0\x0B"));
772                                    if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
773                                        $obj[$key] = $val;
774                                    } else {
775                                        $obj->$key = $val;
776                                    }
777                                } elseif (preg_match('/^\s*(\w+)\s*:/Uis', $slice, $parts)) {
778                                    // name:value pair, where name is unquoted
779                                    $key = $parts[1];
780                                    $val = $this->decode(trim(substr($slice, strlen($parts[0])), ", \t\n\r\0\x0B"));
781
782                                    if ($this->use & SERVICES_JSON_LOOSE_TYPE) {
783                                        $obj[$key] = $val;
784                                    } else {
785                                        $obj->$key = $val;
786                                    }
787                                }
788
789                            }
790
791                        } elseif ((($chrs{$c} == '"') || ($chrs{$c} == "'")) && ($top['what'] != SERVICES_JSON_IN_STR)) {
792                            // found a quote, and we are not inside a string
793                            array_push($stk, array('what' => SERVICES_JSON_IN_STR, 'where' => $c, 'delim' => $chrs{$c}));
794                            //print("Found start of string at {$c}\n");
795
796                        } elseif (($chrs{$c} == $top['delim']) &&
797                                 ($top['what'] == SERVICES_JSON_IN_STR) &&
798                                 (($this->strlen8($this->substr8($chrs, 0, $c)) - $this->strlen8(rtrim($this->substr8($chrs, 0, $c), '\\'))) % 2 != 1)) {
799                            // found a quote, we're in a string, and it's not escaped
800                            // we know that it's not escaped becase there is _not_ an
801                            // odd number of backslashes at the end of the string so far
802                            array_pop($stk);
803                            //print("Found end of string at {$c}: ".$this->substr8($chrs, $top['where'], (1 + 1 + $c - $top['where']))."\n");
804
805                        } elseif (($chrs{$c} == '[') &&
806                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
807                            // found a left-bracket, and we are in an array, object, or slice
808                            array_push($stk, array('what' => SERVICES_JSON_IN_ARR, 'where' => $c, 'delim' => false));
809                            //print("Found start of array at {$c}\n");
810
811                        } elseif (($chrs{$c} == ']') && ($top['what'] == SERVICES_JSON_IN_ARR)) {
812                            // found a right-bracket, and we're in an array
813                            array_pop($stk);
814                            //print("Found end of array at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");
815
816                        } elseif (($chrs{$c} == '{') &&
817                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
818                            // found a left-brace, and we are in an array, object, or slice
819                            array_push($stk, array('what' => SERVICES_JSON_IN_OBJ, 'where' => $c, 'delim' => false));
820                            //print("Found start of object at {$c}\n");
821
822                        } elseif (($chrs{$c} == '}') && ($top['what'] == SERVICES_JSON_IN_OBJ)) {
823                            // found a right-brace, and we're in an object
824                            array_pop($stk);
825                            //print("Found end of object at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");
826
827                        } elseif (($substr_chrs_c_2 == '/*') &&
828                                 in_array($top['what'], array(SERVICES_JSON_SLICE, SERVICES_JSON_IN_ARR, SERVICES_JSON_IN_OBJ))) {
829                            // found a comment start, and we are in an array, object, or slice
830                            array_push($stk, array('what' => SERVICES_JSON_IN_CMT, 'where' => $c, 'delim' => false));
831                            $c++;
832                            //print("Found start of comment at {$c}\n");
833
834                        } elseif (($substr_chrs_c_2 == '*/') && ($top['what'] == SERVICES_JSON_IN_CMT)) {
835                            // found a comment end, and we're in one now
836                            array_pop($stk);
837                            $c++;
838
839                            for ($i = $top['where']; $i <= $c; ++$i)
840                                $chrs = substr_replace($chrs, ' ', $i, 1);
841
842                            //print("Found end of comment at {$c}: ".$this->substr8($chrs, $top['where'], (1 + $c - $top['where']))."\n");
843
844                        }
845
846                    }
847
848                    if (reset($stk) == SERVICES_JSON_IN_ARR) {
849                        return $arr;
850
851                    } elseif (reset($stk) == SERVICES_JSON_IN_OBJ) {
852                        return $obj;
853
854                    }
855
856                }
857        }
858    }
859
860    /**
861     * @todo Ultimately, this should just call PEAR::isError()
862     */
863    function isError($data, $code = null)
864    {
865        if (class_exists('pear')) {
866            return PEAR::isError($data, $code);
867        } elseif (is_object($data) && (get_class($data) == 'services_json_error' ||
868                                 is_subclass_of($data, 'services_json_error'))) {
869            return true;
870        }
871
872        return false;
873    }
874
875    /**
876    * Calculates length of string in bytes
877    * @param string
878    * @return integer length
879    */
880    function strlen8( $str )
881    {
882        if ( $this->_mb_strlen ) {
883            return mb_strlen( $str, "8bit" );
884        }
885        return strlen( $str );
886    }
887
888    /**
889    * Returns part of a string, interpreting $start and $length as number of bytes.
890    * @param string
891    * @param integer start
892    * @param integer length
893    * @return integer length
894    */
895    function substr8( $string, $start, $length=false )
896    {
897        if ( $length === false ) {
898            $length = $this->strlen8( $string ) - $start;
899        }
900        if ( $this->_mb_substr ) {
901            return mb_substr( $string, $start, $length, "8bit" );
902        }
903        return substr( $string, $start, $length );
904    }
905
906}
907
908if (class_exists('PEAR_Error')) {
909
910    class Services_JSON_Error extends PEAR_Error
911    {
912        function Services_JSON_Error($message = 'unknown error', $code = null,
913                                     $mode = null, $options = null, $userinfo = null)
914        {
915            parent::PEAR_Error($message, $code, $mode, $options, $userinfo);
916        }
917    }
918
919} else {
920
921    /**
922     * @todo Ultimately, this class shall be descended from PEAR_Error
923     */
924    class Services_JSON_Error
925    {
926        function Services_JSON_Error($message = 'unknown error', $code = null,
927                                     $mode = null, $options = null, $userinfo = null)
928        {
929
930        }
931    }
932
933}
934