Bring va_list args; to a QStringList or a qmap

I wand capture error from the http://xmlsoft.org/XSLT/ static libs

To display on a xml/xslt editor in order to communicate the customer where it mistakes on xml or xslt....

I found the error handler from php6 on C# code xslt extension

How i can read va_list args; ? what is? and why a function argument end ,...)

Code:

---

PHP_RINIT_FUNCTION(xsl)
{
	xsltSetGenericErrorFunc(NULL, php_libxml_error_handler);
	return SUCCESS;
}
 
PHP_LIBXML_API void php_libxml_error_handler(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
	php_libxml_internal_error_handler(PHP_LIBXML_ERROR, ctx, &msg, args);
	va_end(args);
}

---

Quote:

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Originally Posted by patrik08

How i can read va_list args; ? what is? and why a function argument end ,...)

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On very rare occasions you need a function that can take any number of arguments --- that's when you must use "...".

The most common example is the printf() function. You can pass a single string to it:

Code:

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printf( "some string\n" );

---

but you can also do this:

Code:

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printf( "%s:%d: %s\n", file, line, msg );

---

In both cases you call the same printf() and you can do this because it was declared like this:

Code:

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int printf( const char *format, ... );

---

Now the problem is: how to access those parameters? You don't know their names. That's where va_list comes in. It allows you, together with va_arg, va_start and va_end macros, to access those anonymous arguments.

With va_start you can initialize a list of arguments (you must pass the last named argument to it), so if you have:

Code:

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void foo( int something, int somethingelse, ... );

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you need:

Code:

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void foo( int something, int somethingelse, ... )
{
   va_list args;
   va_start( args, somethingelse );
   // now you can use args
   va_end( args ); // clean up
}

---

With va_args you can access those arguments' values, but you must know their types a priori.

You can find more here: http://www.cppreference.com/stdother/va_arg.html

Quote:

---

Originally Posted by jacek

you need:

Code:

---

void foo( int something, int somethingelse, ... )
{
   va_list args;
   va_start( args, somethingelse );
   // now you can use args
   va_end( args ); // clean up
}

---

With va_args you can access those arguments' values, but you must know their types a priori.

You can find more here: http://www.cppreference.com/stdother/va_arg.html

---

i suppose static void ... i tested a qt4 class + Q_OBJECT not accept ,...):confused:

Code:

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static void foo( int something, int somethingelse, ... )

---

i become ... now.......

### qt_libxml_error_handler ctx 0x0
### qt_libxml_error_handler msg "%s"
### qt_libxml_error_handler arg ?┐\♦
### qt_libxml_error_handler ctx 0x0
I/O warning : failed to load external entity "file:///C%3A/include/_header_page.

QString & QString::sprintf ( const char * cformat, ... )
char buffer [50];
QString message = QString::sprintf (buffer,msg,args); /* crach & qt frozen */

How to reformat this on QString::sprintf ??


the qt code ....

Code:

---

/* from class external function */
void qt_libxml_error_handler(void *ctx, const char *msg, ...)
{
    char buffer [50];
	va_list args;
	va_start(args, msg);
    /*sprintf (buffer,msg,args);*/
    qDebug() << "### qt_libxml_error_handler arg  "  << msg;
    qDebug() << "### qt_libxml_error_handler arg  "  << args;
    qDebug() << "### qt_libxml_error_handler ctx  "  << ctx;
	/*php_libxml_internal_error_handler(PHP_LIBXML_ERROR, ctx, &msg, args);*/
	va_end(args);
}
 
 
 
/*class qt function */
 
QByteArray gocharxslt = DATA_CONVERTER.toAscii();
        xsltSetGenericErrorFunc(NULL, qt_libxml_error_handler);  /* error callback */
        cur = xsltParseStylesheetFile( (const xmlChar*)gocharxslt.data() );
        doc = xmlParseFile( QFile::encodeName(DATA_FILE_XML) );
        outputDoc = xsltApplyStylesheet(cur, doc, params);
        xmlFreeDoc( doc ); /* free ram from xml! */
        doc = outputDoc; /* swap input and output */
        FILE* outfile = fopen( QFile::encodeName( SHORTFILE ), "w" );
        xsltSaveResultToFile( outfile, doc, cur );
        fclose( outfile );
        xsltFreeStylesheet(cur);
        xmlFreeDoc( outputDoc );
        xsltCleanupGlobals();
        xmlCleanupParser();

---

php6 make so .... " grep -R "php_libxml_internal_error_handler" * " Tank to grep :)

Code:

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static void php_libxml_internal_error_handler(int error_type, void *ctx, const char **msg, va_list ap)
{
	char *buf;
	int len, len_iter, output = 0;
 
	TSRMLS_FETCH();
 
	len = vspprintf(&buf, 0, *msg, ap);
	len_iter = len;
 
	/* remove any trailing \n */
	while (len_iter && buf[--len_iter] == '\n') {
		buf[len_iter] = '\0';
		output = 1;
	}
 
	smart_str_appendl(&LIBXML(error_buffer), buf, len);
 
	efree(buf);
 
	if (output == 1) {
		if (LIBXML(error_list)) {
			_php_list_set_error_structure(NULL, LIBXML(error_buffer).c);
		} else {
			switch (error_type) {
				case PHP_LIBXML_CTX_ERROR:
					php_libxml_ctx_error_level(E_WARNING, ctx, LIBXML(error_buffer).c TSRMLS_CC);
					break;
				case PHP_LIBXML_CTX_WARNING:
					php_libxml_ctx_error_level(E_NOTICE, ctx, LIBXML(error_buffer).c TSRMLS_CC);
					break;
				default:
					php_error_docref(NULL TSRMLS_CC, E_WARNING, "%s", LIBXML(error_buffer).c);
			}
		}
		smart_str_free(&LIBXML(error_buffer));
	}
}

---

Code:

---

void qt_libxml_error_handler(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
    char *buffer = new char[255];
    sprintf(buffer, msg, args);
    QString message = QString( "Buffer say %1" ).arg( QString::fromAscii(buffer) );
    qDebug() << "### qt_libxml_error_handler msg   "  << message;
	va_end(args);
}

---

Now qDebug() << "### qt_libxml_error_handler msg " << message;
report this ...

I not say how leng .... char *buffer = new char[255];

output....

Code:

---

### qt_libxml_error_handler msg    "Buffer say ?┐\♦"
I/O warning : failed to load external entity "file:///C%3A/include/_colonna_dest
ra.xsl"
### qt_libxml_error_handler msg    "Buffer say 4↑▓: file file:///C%3A/include/_c
olonna_destra.xsl line 2009252579 element ?─♦?F∟?└t
►?─♦?F ?└t
►?─♦?↨?▬?G♦?F♦?O♀?N♀?W¶?V¶?G0?F0?O$?N$?W(?V(?G0?T$∟?F0?O,?D$►?n►]??N,?L$►[?F∟_?V
↑?N 3└^?├_?╚ ^?├╠╠╠╠╠╠╠╠╠╠?ý►?D$$UV3÷?t$¶?D$♀ÞÏ

---

Quote:

---

Originally Posted by patrik08

QString & QString::sprintf ( const char * cformat, ... )
char buffer [50];
QString message = QString::sprintf (buffer,msg,args); /* crach & qt frozen */

How to reformat this on QString::sprintf ??

---

Code:

---

QString message;
message.sprintf( msg, args );

---

Quote:

---

Originally Posted by jacek

Code:

---

QString message;
message.sprintf( msg, args );

---

---

Crasch and frozen qt....

i tested so...

other sample code go to ...
http://www.opengroup.org/pubs/online.../vfprintf.html
reference http://www.stylusstudio.com/xsllist/...post90770.html

Code:

---

void qt_libxml_error_handler(void *ctx, const char *msg, ...)
{
	va_list args;
	va_start(args, msg);
    qt_libxml_error_line(ctx, msg, args);
	va_end(args);
}
 
void qt_libxml_error_line(void *ctx, const char *msg, va_list ap)
{
    char *buf;
    int len, len_iter, output = 0;
    len = vsprintf( buf , msg, ap);
    len_iter = len;
 
    if (len > 0) {
        qDebug() << "### int is set  ";
    }
 
}

---

now is running :) if i cann not fill a qstringlist .. fill a file and remove on class function....

Code:

---

void qt_libxml_error_handler(void *ctx, const char *msg, ...)
{
	FILE* outfile = fopen( QFile::encodeName(  XMLERROR_FILE ), "a" );;
        va_list args;
        va_start(args, msg);
        vfprintf(outfile, msg, args);
        va_end(args);
    fclose( outfile );
}

---

:D hard work to display error!

Quote:

---

Originally Posted by patrik08

Crasch and frozen qt....

---

OK, the problem is that you can't use va_list instead "...", because it will be treated as a single anonymous parameter and indeed vsprintf is a way to go (or rather vsnprintf as it is safer).

Code:

---

void qt_libxml_error_handler(void *ctx, const char *msg, ...)
{
    va_list args;
    QString message;
 
    in size = 256;
    char * buf = new char[ size ];
 
    while( 1 ) {
       va_start(args, msg);
       int retval = ::vsnprintf( buf, size, msg, args );
       va_end(args);
 
       if( -1 < retval && retval < size ) { // everything was OK
          message = buf;
          break;
       }
       else if( retval > -1 ) { // buffer too small
           size = retval + 1;
           delete [] buf;
           buf = new char[ size ];
       }
       else {  // error
          // ...
          break;
       }
    }
 
    delete [] buf;
 
    // use message
}

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