mkdir.cc

/** Rohit Sindhu [sindh010]
 *  Aravind Alagiri Ramkumar [alagi005]
 *  Aparna Mahadevan [mahad028]
 */
/**
 * An mkdir for a simulated file system.
 * @author Ray Ontko -> Converted to C++ by Kwangsung
 */
#include "Kernel.h"
#include "DirectoryEntry.h"
#include "Stat.h"
#include <stdlib.h>
#include <cstring>

int main(int argc, char ** argv)
{
	char PROGRAM_NAME[8];
	strcpy(PROGRAM_NAME, "mkdir");

	char name[64];
	char parentName[64];

	memset(name, '\0', 64);
	memset(parentName, '\0', 64);

	// initialize the file system simulator kernel
	if(Kernel::initialize() == false)
	{
		cout << "Failed to initialized Kernel" << endl;
		Kernel::exit(1);
	}
	// print a helpful message if no command line arguments are given
	if(argc < 2)
	{
		cout << PROGRAM_NAME << ": too few arguments" << endl;
		Kernel::exit( 1 ) ;
	}

	// create a buffer for writing directory entries
	char directoryEntryBuffer[DirectoryEntry::DIRECTORY_ENTRY_SIZE];
	memset(directoryEntryBuffer, '\0', DirectoryEntry::DIRECTORY_ENTRY_SIZE);

	// for each argument given on the command line
	for( int i = 1 ; i < argc; i ++ )
	{
		strcpy(name, argv[i]);
		int status = 0 ;

		// call creat() to create the file
		int newDir = Kernel::creat( name , Kernel::S_IFDIR ) ;

		if( newDir < 0 )
		{
			Kernel::perror( PROGRAM_NAME ) ;
			cout << PROGRAM_NAME << ": \"" << name << "\"" << endl ;
			Kernel::exit( 2 ) ;
		}

		// get file info for "."
		Stat selfStat;
		status = Kernel::fstat( newDir , selfStat ) ;
		if( status < 0 )
		{
			Kernel::perror( PROGRAM_NAME ) ;
			Kernel::exit( 3 ) ;
		}

//		cout <<"Ino " <<  selfStat.getIno() << endl;

		// add entry for "."
		DirectoryEntry self(selfStat.getIno() , ".");
		memset(directoryEntryBuffer, '\0', DirectoryEntry::DIRECTORY_ENTRY_SIZE);
		self.write( directoryEntryBuffer , 0) ;

//		cout << "From mkdir " << self.toString() << endl;
		status = Kernel::write(newDir, directoryEntryBuffer, DirectoryEntry::DIRECTORY_ENTRY_SIZE ) ;
		if( status < 0 )
		{
			Kernel::perror( PROGRAM_NAME ) ;
			Kernel::exit( 4 ) ;
		}

		// get file info for ".."
		Stat parentStat;

		string fullPath(argv[i]);
		// remove trailing '/'
		fullPath = fullPath.substr(0, fullPath.find_last_not_of("/"));
		string parentDirName = fullPath.substr(0, fullPath.find_last_of("/"));

		sprintf(parentName, parentDirName.c_str());
		Kernel::stat(parentName , parentStat);

		// add entry for ".."
		DirectoryEntry parent(parentStat.getIno() , "..");
		memset(directoryEntryBuffer, '\0', DirectoryEntry::DIRECTORY_ENTRY_SIZE);
		parent.write( directoryEntryBuffer , 0 );

		status = Kernel::write(newDir , directoryEntryBuffer, DirectoryEntry::DIRECTORY_ENTRY_SIZE) ;
		if( status < 0 )
		{
			Kernel::perror( PROGRAM_NAME ) ;
			Kernel::exit( 5 ) ;
		}

		// call close() to close the file
		status = Kernel::close( newDir ) ;
		if( status < 0 )
		{
			Kernel::perror( PROGRAM_NAME ) ;
			Kernel::exit( 6 ) ;
		}

		// Update new directory entry's link count
		FileSystem *fileSystem = Kernel::openFileSystems;
		IndexNode indexNode;

		fileSystem->readIndexNode(&indexNode, selfStat.getIno());
		indexNode.setNlink(2);
		fileSystem->writeIndexNode(&indexNode, selfStat.getIno());
		  
		fileSystem->readIndexNode(&indexNode, parent.getIno());
		indexNode.setNlink(indexNode.getNlink() + 1);
		fileSystem->writeIndexNode(&indexNode, parent.getIno());    
	}

	// exit with success if we process all the arguments
	Kernel::exit( 0 ) ;
}