Description:
------------
Since version 2.7.3 libxml limits the maximum size of a single text node to 10MB.
The limit can be removed with a new option, XML_PARSE_HUGE.
PHP has no way to specify this option to libxml.

I found the bug when making af SOAP-request where the reply contained a 20MB string.
SoapClient->__call() threw an exception: 'looks like we got no XML document'

Using libxml_use_internal_errors(true) and libxml_get_errors() I could narrow it down to a LibXMLError, code 5, 'Extra content at the end of the document' - but the specified line and column was in the middle of a large text node.

Using SoapClient->__getLastResponse() I saved the response to a file.
The xmllib program xmllint then revealed the cause:
> xmllint --noout soap_response.txt 
soap_response.txt:111834: error: xmlSAX2Characters: huge text node: out of memory

We need a way to specify the XML_PARSE_HUGE option to libxml - perhaps something like a new function: libxml_parse_huge(true).


Reproduce code:
---------------
<?php
$xml = "<?xml version='1.0' encoding='utf-8' standalone='yes' ?><test>" . str_repeat('A', 12000000) . "</test>";
file_put_contents('file.xml', $xml);
$sxe = simplexml_load_file('file.xml');
if ($sxe instanceof SimpleXMLElement) {
	echo 'OK\n';
}
else {
	var_dump($sxe);
}


Expected result:
----------------
OK

Actual result:
--------------
PHP Warning:  simplexml_load_file(): file.xml:1: error: xmlSAX2Characters: huge text node: out of memory in /usr/dana/data/developers/holst/mobilmap/cron/xml.php on line 5
PHP Warning:  simplexml_load_file(): AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA in /usr/dana/data/developers/holst/mobilmap/cron/xml.php on line 5
PHP Warning:  simplexml_load_file():                                                                                ^ in /usr/dana/data/developers/holst/mobilmap/cron/xml.php on line 5
bool(false)