comments
[plcapi.git] / src / Helper / XMLParser.php
index 6803ebf..59eec67 100644 (file)
@@ -6,40 +6,60 @@ use PhpXmlRpc\PhpXmlRpc;
 use PhpXmlRpc\Value;
 
 /**
- * Deals with parsing the XML
+ * Deals with parsing the XML.
+ * @see http://xmlrpc.com/spec.md
+ *
+ * @todo implement an interface to allow for alternative implementations
+ *       - make access to $_xh protected, return more high-level data structures
+ *       - add parseRequest, parseResponse, parseValue methods
+ * @todo if iconv() or mb_string() are available, we could allow to convert the received xml to a custom charset encoding
+ *       while parsing, which is faster than doing it later by going over the rebuilt data structure
  */
 class XMLParser
 {
-    // used to store state during parsing
-    // quick explanation of components:
-    //   ac - used to accumulate values
-    //   stack - array with genealogy of xml elements names:
-    //           used to validate nesting of xmlrpc elements
-    //   valuestack - array used for parsing arrays and structs
-    //   lv - used to indicate "looking for a value": implements
-    //        the logic to allow values with no types to be strings
-    //   isf - used to indicate a parsing fault (2) or xmlrpcresp fault (1)
-    //   isf_reason - used for storing xmlrpcresp fault string
-    //   method - used to store method name
-    //   params - used to store parameters in method calls
-    //   pt - used to store the type of each received parameter. Useful if parameters are automatically decoded to php values
-    //   rt  - 'methodcall or 'methodresponse'
+    const RETURN_XMLRPCVALS = 'xmlrpcvals';
+    const RETURN_EPIVALS = 'epivals';
+    const RETURN_PHP = 'phpvals';
+
+    const ACCEPT_REQUEST = 1;
+    const ACCEPT_RESPONSE = 2;
+    const ACCEPT_VALUE = 4;
+    const ACCEPT_FAULT = 8;
+
+    // Used to store state during parsing and to pass parsing results to callers.
+    // Quick explanation of components:
+    //  private:
+    //    ac - used to accumulate values
+    //    stack - array with genealogy of xml elements names used to validate nesting of xmlrpc elements
+    //    valuestack - array used for parsing arrays and structs
+    //    lv - used to indicate "looking for a value": implements the logic to allow values with no types to be strings
+    //  public:
+    //    isf - used to indicate an xml parsing fault (3), invalid xmlrpc fault (2) or xmlrpc response fault (1)
+    //    isf_reason - used for storing xmlrpc response fault string
+    //    value - used to store the value in responses
+    //    method - used to store method name in requests
+    //    params - used to store parameters in requests
+    //    pt - used to store the type of each received parameter. Useful if parameters are automatically decoded to php values
+    //    rt  - 'methodcall', 'methodresponse', 'value' or 'fault' (the last one used only in EPI emulation mode)
     public $_xh = array(
         'ac' => '',
         'stack' => array(),
         'valuestack' => array(),
         'isf' => 0,
         'isf_reason' => '',
-        'method' => false, // so we can check later if we got a methodname or not
+        'value' => null,
+        'method' => false,
         'params' => array(),
         'pt' => array(),
-        'rt' => ''
+        'rt' => '',
     );
 
     public $xmlrpc_valid_parents = array(
         'VALUE' => array('MEMBER', 'DATA', 'PARAM', 'FAULT'),
         'BOOLEAN' => array('VALUE'),
         'I4' => array('VALUE'),
+        'I8' => array('VALUE'),
+        'EX:I8' => array('VALUE'),
         'INT' => array('VALUE'),
         'STRING' => array('VALUE'),
         'DOUBLE' => array('VALUE'),
@@ -55,57 +75,162 @@ class XMLParser
         'PARAMS' => array('METHODCALL', 'METHODRESPONSE'),
         'FAULT' => array('METHODRESPONSE'),
         'NIL' => array('VALUE'), // only used when extension activated
-        'EX:NIL' => array('VALUE') // only used when extension activated
+        'EX:NIL' => array('VALUE'), // only used when extension activated
     );
 
+    /** @var array $parsing_options */
+    protected $parsing_options = array();
+    /** @var int $accept self::ACCEPT_REQUEST | self::ACCEPT_RESPONSE by default */
+    protected $accept = 3;
+    /** @var int $maxChunkLength 4 MB by default. Any value below 10MB should be good */
+    protected $maxChunkLength = 4194304;
+
+    /**
+     * @param array $options passed to the xml parser
+     */
+    public function __construct(array $options = array())
+    {
+        $this->parsing_options = $options;
+    }
+
+    /**
+     * @param string $data
+     * @param string $returnType
+     * @param int $accept a bit-combination of self::ACCEPT_REQUEST, self::ACCEPT_RESPONSE, self::ACCEPT_VALUE
+     */
+    public function parse($data, $returnType = self::RETURN_XMLRPCVALS, $accept = 3)
+    {
+        $this->_xh = array(
+            'ac' => '',
+            'stack' => array(),
+            'valuestack' => array(),
+            'isf' => 0,
+            'isf_reason' => '',
+            'value' => null,
+            'method' => false, // so we can check later if we got a methodname or not
+            'params' => array(),
+            'pt' => array(),
+            'rt' => '',
+        );
+
+        $len = strlen($data);
+
+        // we test for empty documents here to save on resource allocation and simply the chunked-parsing loop below
+        if ($len == 0) {
+            $this->_xh['isf'] = 3;
+            $this->_xh['isf_reason'] = 'XML error 5: empty document';
+            return;
+        }
+
+        $parser = xml_parser_create();
+
+        foreach ($this->parsing_options as $key => $val) {
+            xml_parser_set_option($parser, $key, $val);
+        }
+        // always set this, in case someone tries to disable it via options...
+        xml_parser_set_option($parser, XML_OPTION_CASE_FOLDING, 1);
+
+        xml_set_object($parser, $this);
+
+        switch($returnType) {
+            case self::RETURN_PHP:
+                xml_set_element_handler($parser, 'xmlrpc_se', 'xmlrpc_ee_fast');
+                break;
+            case self::RETURN_EPIVALS:
+                xml_set_element_handler($parser, 'xmlrpc_se', 'xmlrpc_ee_epi');
+                break;
+            default:
+                xml_set_element_handler($parser, 'xmlrpc_se', 'xmlrpc_ee');
+        }
+
+        xml_set_character_data_handler($parser, 'xmlrpc_cd');
+        xml_set_default_handler($parser, 'xmlrpc_dh');
+
+        $this->accept = $accept;
+
+        // @see ticket #70 - we have to parse big xml docks in chunks to avoid errors
+        for ($offset = 0; $offset < $len; $offset += $this->maxChunkLength) {
+            $chunk = substr($data, $offset, $this->maxChunkLength);
+            // error handling: xml not well formed
+            if (!xml_parse($parser, $chunk, $offset + $this->maxChunkLength >= $len)) {
+                $errCode = xml_get_error_code($parser);
+                $errStr = sprintf('XML error %s: %s at line %d, column %d', $errCode, xml_error_string($errCode),
+                    xml_get_current_line_number($parser), xml_get_current_column_number($parser));
+
+                $this->_xh['isf'] = 3;
+                $this->_xh['isf_reason'] = $errStr;
+                break;
+            }
+        }
+
+        xml_parser_free($parser);
+    }
+
     /**
-     * xml parser handler function for opening element tags
+     * xml parser handler function for opening element tags.
+     * @internal
+     * @param resource $parser
+     * @param string $name
+     * @param $attrs
+     * @param bool $acceptSingleVals DEPRECATED use the $accept parameter instead
      */
-    function xmlrpc_se($parser, $name, $attrs, $accept_single_vals=false)
+    public function xmlrpc_se($parser, $name, $attrs, $acceptSingleVals = false)
     {
         // if invalid xmlrpc already detected, skip all processing
-        if ($this->_xh['isf'] < 2)
-        {
+        if ($this->_xh['isf'] < 2) {
+
             // check for correct element nesting
-            // top level element can only be of 2 types
-            /// @todo optimization creep: save this check into a bool variable, instead of using count() every time:
-            ///       there is only a single top level element in xml anyway
-            if (count($this->_xh['stack']) == 0)
-            {
-                if ($name != 'METHODRESPONSE' && $name != 'METHODCALL' && (
-                        $name != 'VALUE' && !$accept_single_vals))
-                {
-                    $this->_xh['isf'] = 2;
-                    $this->_xh['isf_reason'] = 'missing top level xmlrpc element';
-                    return;
+            if (count($this->_xh['stack']) == 0) {
+                // top level element can only be of 2 types
+                /// @todo optimization creep: save this check into a bool variable, instead of using count() every time:
+                ///       there is only a single top level element in xml anyway
+                // BC
+                if ($acceptSingleVals === false) {
+                    $accept = $this->accept;
+                } else {
+                    $accept = self::ACCEPT_REQUEST | self::ACCEPT_RESPONSE | self::ACCEPT_VALUE;
                 }
-                else
-                {
+                if (($name == 'METHODCALL' && ($accept & self::ACCEPT_REQUEST)) ||
+                    ($name == 'METHODRESPONSE' && ($accept & self::ACCEPT_RESPONSE)) ||
+                    ($name == 'VALUE' && ($accept & self::ACCEPT_VALUE)) ||
+                    ($name == 'FAULT' && ($accept & self::ACCEPT_FAULT))) {
                     $this->_xh['rt'] = strtolower($name);
+                } else {
+                    $this->_xh['isf'] = 2;
+                    $this->_xh['isf_reason'] = 'missing top level xmlrpc element. Found: ' . $name;
+
+                    return;
                 }
-            }
-            else
-            {
+            } else {
                 // not top level element: see if parent is OK
                 $parent = end($this->_xh['stack']);
-                if (!array_key_exists($name, $this->xmlrpc_valid_parents) || !in_array($parent, $this->xmlrpc_valid_parents[$name]))
-                {
+                if (!array_key_exists($name, $this->xmlrpc_valid_parents) || !in_array($parent, $this->xmlrpc_valid_parents[$name])) {
                     $this->_xh['isf'] = 2;
                     $this->_xh['isf_reason'] = "xmlrpc element $name cannot be child of $parent";
+
                     return;
                 }
             }
 
-            switch($name)
-            {
+            switch ($name) {
                 // optimize for speed switch cases: most common cases first
                 case 'VALUE':
                     /// @todo we could check for 2 VALUE elements inside a MEMBER or PARAM element
-                    $this->_xh['vt']='value'; // indicator: no value found yet
-                    $this->_xh['ac']='';
-                    $this->_xh['lv']=1;
-                    $this->_xh['php_class']=null;
+                    $this->_xh['vt'] = 'value'; // indicator: no value found yet
+                    $this->_xh['ac'] = '';
+                    $this->_xh['lv'] = 1;
+                    $this->_xh['php_class'] = null;
                     break;
+                case 'I8':
+                case 'EX:I8':
+                    if (PHP_INT_SIZE === 4) {
+                        // INVALID ELEMENT: RAISE ISF so that it is later recognized!!!
+                        $this->_xh['isf'] = 2;
+                        $this->_xh['isf_reason'] = "Received i8 element but php is compiled in 32 bit mode";
+
+                        return;
+                    }
+                    // fall through voluntarily
                 case 'I4':
                 case 'INT':
                 case 'STRING':
@@ -113,43 +238,42 @@ class XMLParser
                 case 'DOUBLE':
                 case 'DATETIME.ISO8601':
                 case 'BASE64':
-                    if ($this->_xh['vt']!='value')
-                    {
-                        //two data elements inside a value: an error occurred!
+                    if ($this->_xh['vt'] != 'value') {
+                        // two data elements inside a value: an error occurred!
                         $this->_xh['isf'] = 2;
                         $this->_xh['isf_reason'] = "$name element following a {$this->_xh['vt']} element inside a single value";
+
                         return;
                     }
-                    $this->_xh['ac']=''; // reset the accumulator
+                    $this->_xh['ac'] = ''; // reset the accumulator
                     break;
                 case 'STRUCT':
                 case 'ARRAY':
-                    if ($this->_xh['vt']!='value')
-                    {
-                        //two data elements inside a value: an error occurred!
+                    if ($this->_xh['vt'] != 'value') {
+                        // two data elements inside a value: an error occurred!
                         $this->_xh['isf'] = 2;
                         $this->_xh['isf_reason'] = "$name element following a {$this->_xh['vt']} element inside a single value";
+
                         return;
                     }
                     // create an empty array to hold child values, and push it onto appropriate stack
-                    $cur_val = array();
-                    $cur_val['values'] = array();
-                    $cur_val['type'] = $name;
+                    $curVal = array();
+                    $curVal['values'] = array();
+                    $curVal['type'] = $name;
                     // check for out-of-band information to rebuild php objs
                     // and in case it is found, save it
-                    if (@isset($attrs['PHP_CLASS']))
-                    {
-                        $cur_val['php_class'] = $attrs['PHP_CLASS'];
+                    if (@isset($attrs['PHP_CLASS'])) {
+                        $curVal['php_class'] = $attrs['PHP_CLASS'];
                     }
-                    $this->_xh['valuestack'][] = $cur_val;
-                    $this->_xh['vt']='data'; // be prepared for a data element next
+                    $this->_xh['valuestack'][] = $curVal;
+                    $this->_xh['vt'] = 'data'; // be prepared for a data element next
                     break;
                 case 'DATA':
-                    if ($this->_xh['vt']!='data')
-                    {
-                        //two data elements inside a value: an error occurred!
+                    if ($this->_xh['vt'] != 'data') {
+                        // two data elements inside a value: an error occurred!
                         $this->_xh['isf'] = 2;
                         $this->_xh['isf_reason'] = "found two data elements inside an array element";
+
                         return;
                     }
                 case 'METHODCALL':
@@ -160,37 +284,37 @@ class XMLParser
                 case 'METHODNAME':
                 case 'NAME':
                     /// @todo we could check for 2 NAME elements inside a MEMBER element
-                    $this->_xh['ac']='';
+                    $this->_xh['ac'] = '';
                     break;
                 case 'FAULT':
-                    $this->_xh['isf']=1;
+                    $this->_xh['isf'] = 1;
                     break;
                 case 'MEMBER':
-                    $this->_xh['valuestack'][count($this->_xh['valuestack'])-1]['name']=''; // set member name to null, in case we do not find in the xml later on
+                    // set member name to null, in case we do not find in the xml later on
+                    $this->_xh['valuestack'][count($this->_xh['valuestack']) - 1]['name'] = '';
                     //$this->_xh['ac']='';
                 // Drop trough intentionally
                 case 'PARAM':
                     // clear value type, so we can check later if no value has been passed for this param/member
-                    $this->_xh['vt']=null;
+                    $this->_xh['vt'] = null;
                     break;
                 case 'NIL':
                 case 'EX:NIL':
-                    if (PhpXmlRpc::$xmlrpc_null_extension)
-                    {
-                        if ($this->_xh['vt']!='value')
-                        {
-                            //two data elements inside a value: an error occurred!
+                    if (PhpXmlRpc::$xmlrpc_null_extension) {
+                        if ($this->_xh['vt'] != 'value') {
+                            // two data elements inside a value: an error occurred!
                             $this->_xh['isf'] = 2;
                             $this->_xh['isf_reason'] = "$name element following a {$this->_xh['vt']} element inside a single value";
+
                             return;
                         }
-                        $this->_xh['ac']=''; // reset the accumulator
+                        $this->_xh['ac'] = ''; // reset the accumulator
                         break;
                     }
                 // we do not support the <NIL/> extension, so
                 // drop through intentionally
                 default:
-                    /// INVALID ELEMENT: RAISE ISF so that it is later recognized!!!
+                    // INVALID ELEMENT: RAISE ISF so that it is later recognized!!!
                     $this->_xh['isf'] = 2;
                     $this->_xh['isf_reason'] = "found not-xmlrpc xml element $name";
                     break;
@@ -200,216 +324,196 @@ class XMLParser
             $this->_xh['stack'][] = $name;
 
             /// @todo optimization creep: move this inside the big switch() above
-            if($name!='VALUE')
-            {
-                $this->_xh['lv']=0;
+            if ($name != 'VALUE') {
+                $this->_xh['lv'] = 0;
             }
         }
     }
 
     /**
-     * Used in decoding xml chunks that might represent single xmlrpc values
+     * xml parser handler function for opening element tags.
+     * Used in decoding xml chunks that might represent single xmlrpc values as well as requests, responses.
+     * @deprecated
+     * @param resource $parser
+     * @param $name
+     * @param $attrs
      */
-    function xmlrpc_se_any($parser, $name, $attrs)
+    public function xmlrpc_se_any($parser, $name, $attrs)
     {
         $this->xmlrpc_se($parser, $name, $attrs, true);
     }
 
     /**
-     * xml parser handler function for close element tags
+     * xml parser handler function for close element tags.
+     * @internal
+     * @param resource $parser
+     * @param string $name
+     * @param int $rebuildXmlrpcvals >1 for rebuilding xmlrpcvals, 0 for rebuilding php values, -1 for xmlrpc-extension compatibility
      */
-    function xmlrpc_ee($parser, $name, $rebuild_xmlrpcvals = true)
+    public function xmlrpc_ee($parser, $name, $rebuildXmlrpcvals = 1)
     {
-        if ($this->_xh['isf'] < 2)
-        {
+        if ($this->_xh['isf'] < 2) {
             // push this element name from stack
             // NB: if XML validates, correct opening/closing is guaranteed and
-            // we do not have to check for $name == $curr_elem.
+            // we do not have to check for $name == $currElem.
             // we also checked for proper nesting at start of elements...
-            $curr_elem = array_pop($this->_xh['stack']);
+            $currElem = array_pop($this->_xh['stack']);
 
-            switch($name)
-            {
+            switch ($name) {
                 case 'VALUE':
                     // This if() detects if no scalar was inside <VALUE></VALUE>
-                    if ($this->_xh['vt']=='value')
-                    {
-                        $this->_xh['value']=$this->_xh['ac'];
-                        $this->_xh['vt']=Value::$xmlrpcString;
+                    if ($this->_xh['vt'] == 'value') {
+                        $this->_xh['value'] = $this->_xh['ac'];
+                        $this->_xh['vt'] = Value::$xmlrpcString;
                     }
 
-                    if ($rebuild_xmlrpcvals)
-                    {
+                    if ($rebuildXmlrpcvals > 0) {
                         // build the xmlrpc val out of the data received, and substitute it
                         $temp = new Value($this->_xh['value'], $this->_xh['vt']);
                         // in case we got info about underlying php class, save it
                         // in the object we're rebuilding
-                        if (isset($this->_xh['php_class']))
+                        if (isset($this->_xh['php_class'])) {
                             $temp->_php_class = $this->_xh['php_class'];
-                        // check if we are inside an array or struct:
-                        // if value just built is inside an array, let's move it into array on the stack
-                        $vscount = count($this->_xh['valuestack']);
-                        if ($vscount && $this->_xh['valuestack'][$vscount-1]['type']=='ARRAY')
-                        {
-                            $this->_xh['valuestack'][$vscount-1]['values'][] = $temp;
                         }
-                        else
-                        {
-                            $this->_xh['value'] = $temp;
+                        $this->_xh['value'] = $temp;
+                    } elseif ($rebuildXmlrpcvals < 0) {
+                        if ($this->_xh['vt'] == Value::$xmlrpcDateTime) {
+                            $this->_xh['value'] = (object)array(
+                                'xmlrpc_type' => 'datetime',
+                                'scalar' => $this->_xh['value'],
+                                'timestamp' => \PhpXmlRpc\Helper\Date::iso8601Decode($this->_xh['value'])
+                            );
+                        } elseif ($this->_xh['vt'] == Value::$xmlrpcBase64) {
+                            $this->_xh['value'] = (object)array(
+                                'xmlrpc_type' => 'base64',
+                                'scalar' => $this->_xh['value']
+                            );
                         }
-                    }
-                    else
-                    {
-                        /// @todo this needs to treat correctly php-serialized objects,
+                    } else {
+                        /// @todo this should handle php-serialized objects,
                         /// since std deserializing is done by php_xmlrpc_decode,
                         /// which we will not be calling...
-                        if (isset($this->_xh['php_class']))
-                        {
-                        }
+                        //if (isset($this->_xh['php_class'])) {
+                        //}
+                    }
 
-                        // check if we are inside an array or struct:
-                        // if value just built is inside an array, let's move it into array on the stack
-                        $vscount = count($this->_xh['valuestack']);
-                        if ($vscount && $this->_xh['valuestack'][$vscount-1]['type']=='ARRAY')
-                        {
-                            $this->_xh['valuestack'][$vscount-1]['values'][] = $this->_xh['value'];
-                        }
+                    // check if we are inside an array or struct:
+                    // if value just built is inside an array, let's move it into array on the stack
+                    $vscount = count($this->_xh['valuestack']);
+                    if ($vscount && $this->_xh['valuestack'][$vscount - 1]['type'] == 'ARRAY') {
+                        $this->_xh['valuestack'][$vscount - 1]['values'][] = $this->_xh['value'];
                     }
                     break;
                 case 'BOOLEAN':
                 case 'I4':
+                case 'I8':
+                case 'EX:I8':
                 case 'INT':
                 case 'STRING':
                 case 'DOUBLE':
                 case 'DATETIME.ISO8601':
                 case 'BASE64':
-                    $this->_xh['vt']=strtolower($name);
+                    $this->_xh['vt'] = strtolower($name);
                     /// @todo: optimization creep - remove the if/elseif cycle below
                     /// since the case() in which we are already did that
-                    if ($name=='STRING')
-                    {
-                        $this->_xh['value']=$this->_xh['ac'];
-                    }
-                    elseif ($name=='DATETIME.ISO8601')
-                    {
-                        if (!preg_match('/^[0-9]{8}T[0-9]{2}:[0-9]{2}:[0-9]{2}$/', $this->_xh['ac']))
-                        {
-                            error_log('XML-RPC: invalid value received in DATETIME: '.$this->_xh['ac']);
+                    if ($name == 'STRING') {
+                        $this->_xh['value'] = $this->_xh['ac'];
+                    } elseif ($name == 'DATETIME.ISO8601') {
+                        if (!preg_match('/^[0-9]{8}T[0-9]{2}:[0-9]{2}:[0-9]{2}$/', $this->_xh['ac'])) {
+                            Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': invalid value received in DATETIME: ' . $this->_xh['ac']);
                         }
-                        $this->_xh['vt']=Value::$xmlrpcDateTime;
-                        $this->_xh['value']=$this->_xh['ac'];
-                    }
-                    elseif ($name=='BASE64')
-                    {
+                        $this->_xh['vt'] = Value::$xmlrpcDateTime;
+                        $this->_xh['value'] = $this->_xh['ac'];
+                    } elseif ($name == 'BASE64') {
                         /// @todo check for failure of base64 decoding / catch warnings
-                        $this->_xh['value']=base64_decode($this->_xh['ac']);
-                    }
-                    elseif ($name=='BOOLEAN')
-                    {
+                        $this->_xh['value'] = base64_decode($this->_xh['ac']);
+                    } elseif ($name == 'BOOLEAN') {
                         // special case here: we translate boolean 1 or 0 into PHP
                         // constants true or false.
                         // Strings 'true' and 'false' are accepted, even though the
                         // spec never mentions them (see eg. Blogger api docs)
                         // NB: this simple checks helps a lot sanitizing input, ie no
                         // security problems around here
-                        if ($this->_xh['ac']=='1' || strcasecmp($this->_xh['ac'], 'true') == 0)
-                        {
-                            $this->_xh['value']=true;
-                        }
-                        else
-                        {
+                        if ($this->_xh['ac'] == '1' || strcasecmp($this->_xh['ac'], 'true') == 0) {
+                            $this->_xh['value'] = true;
+                        } else {
                             // log if receiving something strange, even though we set the value to false anyway
-                            if ($this->_xh['ac']!='0' && strcasecmp($this->_xh['ac'], 'false') != 0)
-                                error_log('XML-RPC: invalid value received in BOOLEAN: '.$this->_xh['ac']);
-                            $this->_xh['value']=false;
+                            if ($this->_xh['ac'] != '0' && strcasecmp($this->_xh['ac'], 'false') != 0) {
+                                Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': invalid value received in BOOLEAN: ' . $this->_xh['ac']);
+                            }
+                            $this->_xh['value'] = false;
                         }
-                    }
-                    elseif ($name=='DOUBLE')
-                    {
+                    } elseif ($name == 'DOUBLE') {
                         // we have a DOUBLE
                         // we must check that only 0123456789-.<space> are characters here
                         // NOTE: regexp could be much stricter than this...
-                        if (!preg_match('/^[+-eE0123456789 \t.]+$/', $this->_xh['ac']))
-                        {
+                        if (!preg_match('/^[+-eE0123456789 \t.]+$/', $this->_xh['ac'])) {
                             /// @todo: find a better way of throwing an error than this!
-                            error_log('XML-RPC: non numeric value received in DOUBLE: '.$this->_xh['ac']);
-                            $this->_xh['value']='ERROR_NON_NUMERIC_FOUND';
-                        }
-                        else
-                        {
+                            Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': non numeric value received in DOUBLE: ' . $this->_xh['ac']);
+                            $this->_xh['value'] = 'ERROR_NON_NUMERIC_FOUND';
+                        } else {
                             // it's ok, add it on
-                            $this->_xh['value']=(double)$this->_xh['ac'];
+                            $this->_xh['value'] = (double)$this->_xh['ac'];
                         }
-                    }
-                    else
-                    {
-                        // we have an I4/INT
+                    } else {
+                        // we have an I4/I8/INT
                         // we must check that only 0123456789-<space> are characters here
-                        if (!preg_match('/^[+-]?[0123456789 \t]+$/', $this->_xh['ac']))
-                        {
+                        if (!preg_match('/^[+-]?[0123456789 \t]+$/', $this->_xh['ac'])) {
                             /// @todo find a better way of throwing an error than this!
-                            error_log('XML-RPC: non numeric value received in INT: '.$this->_xh['ac']);
-                            $this->_xh['value']='ERROR_NON_NUMERIC_FOUND';
-                        }
-                        else
-                        {
+                            Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': non numeric value received in INT: ' . $this->_xh['ac']);
+                            $this->_xh['value'] = 'ERROR_NON_NUMERIC_FOUND';
+                        } else {
                             // it's ok, add it on
-                            $this->_xh['value']=(int)$this->_xh['ac'];
+                            $this->_xh['value'] = (int)$this->_xh['ac'];
                         }
                     }
-                    //$this->_xh['ac']=''; // is this necessary?
-                    $this->_xh['lv']=3; // indicate we've found a value
+                    $this->_xh['lv'] = 3; // indicate we've found a value
                     break;
                 case 'NAME':
-                    $this->_xh['valuestack'][count($this->_xh['valuestack'])-1]['name'] = $this->_xh['ac'];
+                    $this->_xh['valuestack'][count($this->_xh['valuestack']) - 1]['name'] = $this->_xh['ac'];
                     break;
                 case 'MEMBER':
-                    //$this->_xh['ac']=''; // is this necessary?
                     // add to array in the stack the last element built,
                     // unless no VALUE was found
-                    if ($this->_xh['vt'])
-                    {
+                    if ($this->_xh['vt']) {
                         $vscount = count($this->_xh['valuestack']);
-                        $this->_xh['valuestack'][$vscount-1]['values'][$this->_xh['valuestack'][$vscount-1]['name']] = $this->_xh['value'];
-                    } else
-                        error_log('XML-RPC: missing VALUE inside STRUCT in received xml');
+                        $this->_xh['valuestack'][$vscount - 1]['values'][$this->_xh['valuestack'][$vscount - 1]['name']] = $this->_xh['value'];
+                    } else {
+                        Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': missing VALUE inside STRUCT in received xml');
+                    }
                     break;
                 case 'DATA':
-                    //$this->_xh['ac']=''; // is this necessary?
-                    $this->_xh['vt']=null; // reset this to check for 2 data elements in a row - even if they're empty
+                    $this->_xh['vt'] = null; // reset this to check for 2 data elements in a row - even if they're empty
                     break;
                 case 'STRUCT':
                 case 'ARRAY':
                     // fetch out of stack array of values, and promote it to current value
-                    $curr_val = array_pop($this->_xh['valuestack']);
-                    $this->_xh['value'] = $curr_val['values'];
-                    $this->_xh['vt']=strtolower($name);
-                    if (isset($curr_val['php_class']))
-                    {
-                        $this->_xh['php_class'] = $curr_val['php_class'];
+                    $currVal = array_pop($this->_xh['valuestack']);
+                    $this->_xh['value'] = $currVal['values'];
+                    $this->_xh['vt'] = strtolower($name);
+                    if (isset($currVal['php_class'])) {
+                        $this->_xh['php_class'] = $currVal['php_class'];
                     }
                     break;
                 case 'PARAM':
                     // add to array of params the current value,
                     // unless no VALUE was found
-                    if ($this->_xh['vt'])
-                    {
-                        $this->_xh['params'][]=$this->_xh['value'];
-                        $this->_xh['pt'][]=$this->_xh['vt'];
+                    if ($this->_xh['vt']) {
+                        $this->_xh['params'][] = $this->_xh['value'];
+                        $this->_xh['pt'][] = $this->_xh['vt'];
+                    } else {
+                        Logger::instance()->errorLog('XML-RPC: ' . __METHOD__ . ': missing VALUE inside PARAM in received xml');
                     }
-                    else
-                        error_log('XML-RPC: missing VALUE inside PARAM in received xml');
                     break;
                 case 'METHODNAME':
-                    $this->_xh['method']=preg_replace('/^[\n\r\t ]+/', '', $this->_xh['ac']);
+                    $this->_xh['method'] = preg_replace('/^[\n\r\t ]+/', '', $this->_xh['ac']);
                     break;
                 case 'NIL':
                 case 'EX:NIL':
-                    if (PhpXmlRpc::$xmlrpc_null_extension)
-                    {
-                        $this->_xh['vt']='null';
-                        $this->_xh['value']=null;
-                        $this->_xh['lv']=3;
+                    if (PhpXmlRpc::$xmlrpc_null_extension) {
+                        $this->_xh['vt'] = 'null';
+                        $this->_xh['value'] = null;
+                        $this->_xh['lv'] = 3;
                         break;
                     }
                 // drop through intentionally if nil extension not enabled
@@ -427,38 +531,41 @@ class XMLParser
     }
 
     /**
-     * Used in decoding xmlrpc requests/responses without rebuilding xmlrpc Values
+     * Used in decoding xmlrpc requests/responses without rebuilding xmlrpc Values.
+     * @internal
+     * @param resource $parser
+     * @param string $name
      */
-    function xmlrpc_ee_fast($parser, $name)
+    public function xmlrpc_ee_fast($parser, $name)
     {
-        $this->xmlrpc_ee($parser, $name, false);
+        $this->xmlrpc_ee($parser, $name, 0);
     }
 
     /**
-     * xml parser handler function for character data
+     * Used in decoding xmlrpc requests/responses while building xmlrpc-extension Values (plain php for all but base64 and datetime).
+     * @internal
+     * @param resource $parser
+     * @param string $name
      */
-    function xmlrpc_cd($parser, $data)
+    public function xmlrpc_ee_epi($parser, $name)
+    {
+        $this->xmlrpc_ee($parser, $name, -1);
+    }
+
+    /**
+     * xml parser handler function for character data.
+     * @internal
+     * @param resource $parser
+     * @param string $data
+     */
+    public function xmlrpc_cd($parser, $data)
     {
         // skip processing if xml fault already detected
-        if ($this->_xh['isf'] < 2)
-        {
+        if ($this->_xh['isf'] < 2) {
             // "lookforvalue==3" means that we've found an entire value
             // and should discard any further character data
-            if($this->_xh['lv']!=3)
-            {
-                // G. Giunta 2006-08-23: useless change of 'lv' from 1 to 2
-                //if($this->_xh['lv']==1)
-                //{
-                // if we've found text and we're just in a <value> then
-                // say we've found a value
-                //$this->_xh['lv']=2;
-                //}
-                // we always initialize the accumulator before starting parsing, anyway...
-                //if(!@isset($this->_xh['ac']))
-                //{
-                //    $this->_xh['ac'] = '';
-                //}
-                $this->_xh['ac'].=$data;
+            if ($this->_xh['lv'] != 3) {
+                $this->_xh['ac'] .= $data;
             }
         }
     }
@@ -466,23 +573,144 @@ class XMLParser
     /**
      * xml parser handler function for 'other stuff', ie. not char data or
      * element start/end tag. In fact it only gets called on unknown entities...
+     * @internal
+     * @param $parser
+     * @param string data
      */
-    function xmlrpc_dh($parser, $data)
+    public function xmlrpc_dh($parser, $data)
     {
         // skip processing if xml fault already detected
-        if ($this->_xh['isf'] < 2)
-        {
-            if(substr($data, 0, 1) == '&' && substr($data, -1, 1) == ';')
-            {
-                // G. Giunta 2006-08-25: useless change of 'lv' from 1 to 2
-                //if($this->_xh['lv']==1)
-                //{
-                //    $this->_xh['lv']=2;
-                //}
-                $this->_xh['ac'].=$data;
+        if ($this->_xh['isf'] < 2) {
+            if (substr($data, 0, 1) == '&' && substr($data, -1, 1) == ';') {
+                $this->_xh['ac'] .= $data;
+            }
+        }
+
+        //return true;
+    }
+
+    /**
+     * xml charset encoding guessing helper function.
+     * Tries to determine the charset encoding of an XML chunk received over HTTP.
+     * NB: according to the spec (RFC 3023), if text/xml content-type is received over HTTP without a content-type,
+     * we SHOULD assume it is strictly US-ASCII. But we try to be more tolerant of non conforming (legacy?) clients/servers,
+     * which will be most probably using UTF-8 anyway...
+     * In order of importance checks:
+     * 1. http headers
+     * 2. BOM
+     * 3. XML declaration
+     * 4. guesses using mb_detect_encoding()
+     *
+     * @param string $httpHeader the http Content-type header
+     * @param string $xmlChunk xml content buffer
+     * @param string $encodingPrefs comma separated list of character encodings to be used as default (when mb extension is enabled).
+     *                              This can also be set globally using PhpXmlRpc::$xmlrpc_detectencodings
+     * @return string the encoding determined. Null if it can't be determined and mbstring is enabled,
+     *                PhpXmlRpc::$xmlrpc_defencoding if it can't be determined and mbstring is not enabled
+     *
+     * @todo explore usage of mb_http_input(): does it detect http headers + post data? if so, use it instead of hand-detection!!!
+     */
+    public static function guessEncoding($httpHeader = '', $xmlChunk = '', $encodingPrefs = null)
+    {
+        // discussion: see http://www.yale.edu/pclt/encoding/
+        // 1 - test if encoding is specified in HTTP HEADERS
+
+        // Details:
+        // LWS:           (\13\10)?( |\t)+
+        // token:         (any char but excluded stuff)+
+        // quoted string: " (any char but double quotes and control chars)* "
+        // header:        Content-type = ...; charset=value(; ...)*
+        //   where value is of type token, no LWS allowed between 'charset' and value
+        // Note: we do not check for invalid chars in VALUE:
+        //   this had better be done using pure ereg as below
+        // Note 2: we might be removing whitespace/tabs that ought to be left in if
+        //   the received charset is a quoted string. But nobody uses such charset names...
+
+        /// @todo this test will pass if ANY header has charset specification, not only Content-Type. Fix it?
+        $matches = array();
+        if (preg_match('/;\s*charset\s*=([^;]+)/i', $httpHeader, $matches)) {
+            return strtoupper(trim($matches[1], " \t\""));
+        }
+
+        // 2 - scan the first bytes of the data for a UTF-16 (or other) BOM pattern
+        //     (source: http://www.w3.org/TR/2000/REC-xml-20001006)
+        //     NOTE: actually, according to the spec, even if we find the BOM and determine
+        //     an encoding, we should check if there is an encoding specified
+        //     in the xml declaration, and verify if they match.
+        /// @todo implement check as described above?
+        /// @todo implement check for first bytes of string even without a BOM? (It sure looks harder than for cases WITH a BOM)
+        if (preg_match('/^(\x00\x00\xFE\xFF|\xFF\xFE\x00\x00|\x00\x00\xFF\xFE|\xFE\xFF\x00\x00)/', $xmlChunk)) {
+            return 'UCS-4';
+        } elseif (preg_match('/^(\xFE\xFF|\xFF\xFE)/', $xmlChunk)) {
+            return 'UTF-16';
+        } elseif (preg_match('/^(\xEF\xBB\xBF)/', $xmlChunk)) {
+            return 'UTF-8';
+        }
+
+        // 3 - test if encoding is specified in the xml declaration
+        // Details:
+        // SPACE:         (#x20 | #x9 | #xD | #xA)+ === [ \x9\xD\xA]+
+        // EQ:            SPACE?=SPACE? === [ \x9\xD\xA]*=[ \x9\xD\xA]*
+        if (preg_match('/^<\?xml\s+version\s*=\s*' . "((?:\"[a-zA-Z0-9_.:-]+\")|(?:'[a-zA-Z0-9_.:-]+'))" .
+            '\s+encoding\s*=\s*' . "((?:\"[A-Za-z][A-Za-z0-9._-]*\")|(?:'[A-Za-z][A-Za-z0-9._-]*'))/",
+            $xmlChunk, $matches)) {
+            return strtoupper(substr($matches[2], 1, -1));
+        }
+
+        // 4 - if mbstring is available, let it do the guesswork
+        if (extension_loaded('mbstring')) {
+            if ($encodingPrefs == null && PhpXmlRpc::$xmlrpc_detectencodings != null) {
+                $encodingPrefs = PhpXmlRpc::$xmlrpc_detectencodings;
             }
+            if ($encodingPrefs) {
+                $enc = mb_detect_encoding($xmlChunk, $encodingPrefs);
+            } else {
+                $enc = mb_detect_encoding($xmlChunk);
+            }
+            // NB: mb_detect likes to call it ascii, xml parser likes to call it US_ASCII...
+            // IANA also likes better US-ASCII, so go with it
+            if ($enc == 'ASCII') {
+                $enc = 'US-' . $enc;
+            }
+
+            return $enc;
+        } else {
+            // no encoding specified: as per HTTP1.1 assume it is iso-8859-1?
+            // Both RFC 2616 (HTTP 1.1) and 1945 (HTTP 1.0) clearly state that for text/xxx content types
+            // this should be the standard. And we should be getting text/xml as request and response.
+            // BUT we have to be backward compatible with the lib, which always used UTF-8 as default...
+            return PhpXmlRpc::$xmlrpc_defencoding;
         }
-        return true;
     }
 
-}
\ No newline at end of file
+    /**
+     * Helper function: checks if an xml chunk as a charset declaration (BOM or in the xml declaration)
+     *
+     * @param string $xmlChunk
+     * @return bool
+     */
+    public static function hasEncoding($xmlChunk)
+    {
+        // scan the first bytes of the data for a UTF-16 (or other) BOM pattern
+        //     (source: http://www.w3.org/TR/2000/REC-xml-20001006)
+        if (preg_match('/^(\x00\x00\xFE\xFF|\xFF\xFE\x00\x00|\x00\x00\xFF\xFE|\xFE\xFF\x00\x00)/', $xmlChunk)) {
+            return true;
+        } elseif (preg_match('/^(\xFE\xFF|\xFF\xFE)/', $xmlChunk)) {
+            return true;
+        } elseif (preg_match('/^(\xEF\xBB\xBF)/', $xmlChunk)) {
+            return true;
+        }
+
+        // test if encoding is specified in the xml declaration
+        // Details:
+        // SPACE:         (#x20 | #x9 | #xD | #xA)+ === [ \x9\xD\xA]+
+        // EQ:            SPACE?=SPACE? === [ \x9\xD\xA]*=[ \x9\xD\xA]*
+        if (preg_match('/^<\?xml\s+version\s*=\s*' . "((?:\"[a-zA-Z0-9_.:-]+\")|(?:'[a-zA-Z0-9_.:-]+'))" .
+            '\s+encoding\s*=\s*' . "((?:\"[A-Za-z][A-Za-z0-9._-]*\")|(?:'[A-Za-z][A-Za-z0-9._-]*'))/",
+            $xmlChunk, $matches)) {
+            return true;
+        }
+
+        return false;
+    }
+}