Parse the spf header and check schema_identifiers against compiled schema

src/ifcparse/IfcSpfHeader.cpp

@@ -0,0 +1,108 @@
+/********************************************************************************
+ *                                                                              *
+ * This file is part of IfcOpenShell.                                           *
+ *                                                                              *
+ * IfcOpenShell is free software: you can redistribute it and/or modify         *
+ * it under the terms of the Lesser GNU General Public License as published by  *
+ * the Free Software Foundation, either version 3.0 of the License, or          *
+ * (at your option) any later version.                                          *
+ *                                                                              *
+ * IfcOpenShell 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                 *
+ * Lesser GNU General Public License for more details.                          *
+ *                                                                              *
+ * You should have received a copy of the Lesser GNU General Public License     *
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.         *
+ *                                                                              *
+ ********************************************************************************/
+
+#include "../ifcparse/IfcParse.h"
+
+#include "IfcSpfHeader.h"
+
+static const char * const ISO_10303_21		= "ISO-10303-21";
+static const char * const HEADER			= "HEADER";
+static const char * const FILE_DESCRIPTION	= "FILE_DESCRIPTION";
+static const char * const FILE_NAME			= "FILE_NAME";
+static const char * const FILE_SCHEMA		= "FILE_SCHEMA";
+static const char * const FILE_POPULATION	= "FILE_POPULATION";
+static const char * const SECTION_LANGUAGE	= "SECTION_LANGUAGE";
+static const char * const SECTION_CONTEXT	= "SECTION_CONTEXT";
+static const char * const ENDSEC			= "ENDSEC";
+static const char * const DATA				= "DATA";
+
+using namespace IfcParse;
+
+void IfcSpfHeader::readSemicolon() {
+	if (!TokenFunc::isOperator(_lexer->Next(), ';')) {
+		throw IfcException(std::string("Expected ;"));
+	}
+}
+
+void IfcSpfHeader::readParen() {
+	if (!TokenFunc::isOperator(_lexer->Next(), '(')) {
+		throw IfcException(std::string("Expected ("));
+	}
+}
+
+void IfcSpfHeader::readTerminal(const std::string& term, Trail trail) {
+	if (TokenFunc::asString(_lexer->Next()) != term) {
+		throw IfcException(std::string("Expected " + term));
+	}
+	if (trail == TRAILING_SEMICOLON) {
+		readSemicolon();
+	} else if (trail == TRAILING_PAREN) {
+		readParen();
+	}
+}
+
+void IfcSpfHeader::read() {
+	readTerminal(ISO_10303_21, TRAILING_SEMICOLON);
+	readTerminal(HEADER, TRAILING_SEMICOLON);
+
+	readTerminal(FILE_DESCRIPTION, TRAILING_PAREN);
+	_file_description = new FileDescription(_lexer);
+	readSemicolon();
+
+	readTerminal(FILE_NAME, TRAILING_PAREN);
+	_file_name = new FileName(_lexer);
+	readSemicolon();
+
+	readTerminal(FILE_SCHEMA, TRAILING_PAREN);
+	_file_schema = new FileSchema(_lexer);
+	readSemicolon();
+}
+
+bool IfcSpfHeader::tryRead() {
+	try {
+		read();
+		return true;
+	} catch(const IfcException&) { 
+		return false;
+	}		
+}
+
+const FileDescription& IfcSpfHeader::file_description() {
+	if (_file_description) {
+		return *_file_description; 
+	} else {
+		throw IfcException("File description not read");
+	}
+}
+
+const FileName& IfcSpfHeader::file_name() {
+	if (_file_name) {
+		return *_file_name; 
+	} else {
+		throw IfcException("File name not read");
+	}
+}
+
+const FileSchema& IfcSpfHeader::file_schema() {
+	if (_file_schema) {
+		return *_file_schema; 
+	} else {
+		throw IfcException("File schema not read");
+	}
+}