Merge pull request #3 from saurabhb17/master

secondary files

1 files changed, 96 insertions, 0 deletions

diff --git a/include/ptree.h b/include/ptree.h
new file mode 100644
index 0000000..a117462
--- /dev/null
+++ b/include/ptree.h
@@ -0,0 +1,96 @@
+#ifndef PTREE_H_
+#define PTREE_H_
+
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2013 SoftPLC Corporation, Dick Hollenbeck <dick@softplc.com>
+ * Copyright (C) 2013 KiCad Developers, see CHANGELOG.TXT for contributors.
+ *
+ * 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, you may find one here:
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+ * or you may search the http://www.gnu.org website for the version 2 license,
+ * or you may write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+ */
+
+
+/*
+
+Implement "KiCad s-epression" support for boost::property_tree's ptree, the 8
+bit string version of property_tree. The ram resident structure of the ptree is
+mostly compatible with one created using the xml_parser from
+boost::property_tree, with slight differences in the way atoms are stored. The
+result is you can use Format() to convert from xml to s-expression, but not the
+other way around. You can write a simple s-expression beautifier in just a few
+lines of code.
+
+The main value however is the s-expression parser, i.e. Scan(), which is an
+alternative to crafting a custom recursive descent parser for a particular
+grammar. The tipping point depends on whether you want to read only a small
+portion of a much larger document. If so, then using the ptree will likely be a
+"faster to code" route. Documentation on how to navigate a ptree can be found on
+the boost website and there are a number of examples in the
+pcbnew/eagle_plugin.cpp file in this project. Powerful path navigation support
+makes it easy to extract a subset of a ptree.
+
+*/
+
+
+#include <boost/property_tree/ptree_fwd.hpp>
+#include <richio.h>
+#include <dsnlexer.h>
+
+typedef boost::property_tree::ptree         PTREE;
+typedef const PTREE                         CPTREE;
+typedef boost::property_tree::ptree_error   PTREE_ERROR;
+
+/**
+ * Function Scan
+ * fills an empty PTREE with information from a KiCad s-expresion stream.  Use
+ * a DSNLEXER with an empty keyword table as @a aLexer.  Useful for parsing
+ * s-expression files or strings of arbitrary grammars, say from a file or clipboard.
+ * The s-expression must be "KiCad compatible".  See Documentation/s-expressions.txt
+ * for this KiCad compatible definition (it is the non-specctra mode).
+ * And also see in tools/property_tree.cpp for example usage.
+ *
+ * <code>
+ *
+ * FILE* fp = fopen( argv[1], "r" );
+ *
+ * static const KEYWORD empty_keywords[1] = {};
+ *
+ * DSNLEXER   lexer( empty_keywords, 0, fp, wxString( FROM_UTF8( argv[1] ) ) );
+ *
+ * try
+ * {
+ *     PTREE   doc;
+ *     Scan( &doc, &lexer );
+ * }
+ * catch( const IO_ERROR& ioe )
+ * {
+ *     fprintf( stderr, "%s\n", TO_UTF8( ioe.errorText ) );
+ * }
+ *
+ * </code>
+ */
+void Scan( PTREE* aTree, DSNLEXER* aLexer ) throw ( IO_ERROR );
+
+/**
+ * Function Format
+ * outputs a PTREE into s-expression format via an OUTPUTFORMATTER derivative.
+ */
+void Format( OUTPUTFORMATTER* out, int aNestLevel, int aCtl, CPTREE& aTree ) throw( IO_ERROR );
+
+#endif  // PTREE_H_