Re: [xml] xmlReadMemory : error "Extra content at the end of the document"

["Elvis Stansvik" <elvstone gmail com>]

Hi,

First of all, please always state your platform and libxml2 version
when asking for help. Also provide a complete standalone code example
of your problem.

2008/11/13 Andrew Hartley <andrew hartley bcs org uk>:
> I have written a DLL with a large (size = 1318109 chars) XML stored as a
> resource.  I read the XML into a std::string and load it with a call to
> xmlReadMemory:
>
> xmlDocPtr pXmlDoc = xmlReadMemory(sXml, sXml.length(), "xml", NULL, 0);

This will never work. libxml2 is C not C++ and the API only works with
NULL terminated sequences of UTF-8 bytes, not STL strings.

> This works fine in Debug mode.  But when I switch to Release mode I get NULL
> returned and the error text is "Extra content at the end of the document".
>
> I have tried parsing the std::string content into a char*, and setting the
> argv[3] to "UTF-8":
>
>             int nLen = (int)sXml.size();
>        char* pszContent        = new char[nLen +2];
>
>        strcpy_s(pszContent, nLen +2, sXml.c_str());
>        pszContent[nLen]                = '\n';
>        pszContent[nLen +1]     = '\0';
>
>        xmlDocPtr pXmlDoc = xmlReadMemory(pszContent, nLen, "xml", "UTF-8", 0);
>
>        delete[] pszContent;
>        pszContent = NULL;
>
> But I still get the same error!

Your example works here (libxml2 on GNU/Linux):

#include <string.h>
#include <libxml/parser.h>
#include <iostream>

int main (int argc, char *argv[])
{
    LIBXML_TEST_VERSION

    std::string sXml("<foo/>");
    int nLen = (int)sXml.size();
    char* pszContent = new char[nLen + 2];

    strncpy(pszContent, sXml.c_str(), nLen + 2);
    pszContent[nLen] = '\n';
    pszContent[nLen + 1] = '\0';

    xmlDocPtr pXmlDoc = xmlReadMemory(pszContent, nLen, "xml", "UTF-8", 0);
    if (pXmlDoc == NULL)
        return(1);

    delete[] pszContent;
    pszContent = NULL;

    xmlFreeDoc(pXmlDoc);
    xmlCleanupParser();

    return(0);
}

[astan franz ~]$ g++ -o test `xml2-config --libs --cflags` test.cpp
[astan franz ~]$ ./test
[astan franz ~]$ echo $?
0
[astan franz ~]$

Though the reason you are adding an extra newline after the XML eludes
me at the moment. Note that I had to use strncpy instead of strcpy_s,
as I'm on GNU/Linux where strcpy_s doesn't exist.

Regards,
Elvis

> I have not resorted to attemting to debug through LibXml2 yet, and would
> appreciate any advice.
> --
> View this message in context: 
> http://www.nabble.com/xmlReadMemory-%3A-error-%22Extra-content-at-the-end-of-the-document%22-tp20484750p20484750.html
> Sent from the Gnome - Lib - Xml - General mailing list archive at Nabble.com.
>
> _______________________________________________
> xml mailing list, project page  http://xmlsoft.org/
> xml gnome org
> http://mail.gnome.org/mailman/listinfo/xml