make output folder if it does not exist

modules/PhysiCell_settings.cpp

@@ -65,6 +65,7 @@
 ###############################################################################
 */
 
+#include <sys/stat.h>
 #include "./PhysiCell_settings.h"
 
 using namespace BioFVM; 
@@ -108,6 +109,8 @@ bool load_PhysiCell_config_file( std::string filename )
 
 	parameters.read_from_pugixml( physicell_config_root ); 
 
+	create_output_directory( PhysiCell_settings.folder );
+
 	return true; 	
 }
 
@@ -320,6 +323,45 @@ void PhysiCell_Settings::read_from_pugixml( void )
 	return; 
 }
 
+bool create_directories(const std::string &path)
+{
+	std::vector<std::string> directories;
+	size_t pos = 0;
+    std::string currentPath;
+
+    while ((pos = path.find_first_of("/\\", pos)) != std::string::npos) {
+        currentPath = path.substr(0, pos++);
+        if (!create_directory(currentPath)) {
+            return false;
+        }
+    }
+    return create_directory(path);
+}
+
+bool create_directory(const std::string &path)
+{
+#if defined(__MINGW32__) || defined(__MINGW64__)
+	bool success = mkdir(path.c_str()) == 0;
+#else
+	bool success = mkdir(path.c_str(), 0755) == 0;
+#endif
+	return success || errno == EEXIST;
+}
+
+void create_output_directory(const std::string& path)
+{
+	if (!create_directories(path))
+	{
+		std::cout << "ERROR: Could not create output directory " << path << " ! Quitting." << std::endl;
+		exit(-1);
+	}
+}
+
+void create_output_directory(void)
+{
+	create_output_directory(PhysiCell_settings.folder);
+}
+
 PhysiCell_Globals PhysiCell_globals; 
 
 /* parameters functions */ 

modules/PhysiCell_settings.h

@@ -137,6 +137,12 @@ class PhysiCell_Settings
 	void read_from_pugixml( void ); 
 };
 
+bool create_directories(const std::string &path);
+bool create_directory(const std::string &path);
+
+void create_output_directory(const std::string& path);
+void create_output_directory(void);
+
 class PhysiCell_Globals
 {
  private: