perl_predicate.c

该软件可以方便的把HTML网页解析成一棵Tree

/*
**	HTML::Tree
**	perl_predicate.c
**
**	Copyright (C) 2001  Paul J. Lucas
**
**	This program is free software; you can redistribute it and/or modify
**	it under the terms of the GNU General Public License as published by
**	the Free Software Foundation; either version 2 of the License, or
**	(at your option) any later version.
**
**	This program is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**	GNU General Public License for more details.
**
**	You should have received a copy of the GNU General Public License
**	along with this program; if not, write to the Free Software
**	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

// Perl
#define	PERL_NO_GET_CONTEXT
extern "C" {
#include <XSUB.h>
}

// local
#include "util.h"			/* must go first */
#include "blessed.h"
#include "managed_ptr.h"
#include "perl_predicate.h"

#ifndef PJL_NO_NAMESPACES
using namespace HTML_Tree;
#endif

//*****************************************************************************
//
// SYNOPSIS
//
	/* virtual */ bool perl_predicate::operator()( HTML_Node &node ) const
//
// DESCRIPTION
//
//	Call the Perl predicate function on the given node and return the Perl
//	function's value.
//
// PARAMETERS
//
//	node	The HTML node being tested by the predicate.
//
// RETURN VALUE
//
//	Returns true only if the predicate is true.
//
// SEE ALSO
//
//	Sriram Srinivasan. "Advanced Perl Programming," O'Reilly and
//	Associates, Inc., Sebastopol, CA, 1997, pp. 352-353.
//
//*****************************************************************************
{
	dTHX;
	dSP;
	ENTER;
	SAVETMPS;
	PUSHMARK( sp );
	XPUSHs( blessed( "HTML::Tree", new managed_node( &node ) ) );
	PUTBACK;
	int const result_count = perl_call_sv( func_ref_, G_SCALAR );
	SPAGAIN;
	if ( result_count != 1 )
		croak(	"HTML::Tree: predicate function "
			"didn't return a single scalar value "
			"(it returned %d)", result_count
		);
#ifdef	SvIVx_BROKEN_GCC
	I32 const ax = (--SP - PL_stack_base) + 1;
	bool const result = SvIV( ST(0) );
#else
	bool const result = POPi;
#endif
	PUTBACK;
	FREETMPS;
	LEAVE;
	return result;
}