/*
 * This is a driver program for the directory hashing homework
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>

#define printf	( void )printf
#define fprintf	( void )fprintf
#define strcpy	( void )strcpy

typedef int HashTbl;	/* dummy declaration - you may need to change this */

static HashTbl H;	/* dummy declaration - you may need to change this */

void
Print( const HashTbl H );

struct dirent *
Find( DIR *DirStream, const char *FileName, const HashTbl H );

struct dirent *
Insert( DIR *DirStream, const char *FileName, const HashTbl H );

/*
 * This array contains a list of files for you to Find(). You can
 * add your own files to the end, if you wish. The files in the array
 * must all be in whatever directory it is that you open (default is
 * /bin, but you can change that for testing purposes).
 */
static char *
Files[] = {
    "ls",
    "rm",
    "cat",
    "mv",
    "vi",
    "ed",
    /* add some more names of /bin files here, if you want */
    NULL
};

int
main( void )
{
    int i;				/* a counter */

    /*
     * pointers for use with dirent routines
     */
    DIR *DirStream;
    struct dirent *DirEntPtr;

    /*
     * this variable is used to hold a copy of the d_name - it
     * keeps data from being corrupted under certain circumstances
     */
    char FileName[ MAXNAMLEN ];

    /*
     * open a directory stream - use of /bin is suggested here
     * because its files are static and there are lots of them
     */
    if( ( DirStream = opendir( "/bin" ) ) != NULL )
    {
	/*
	 * read directory entries and Insert() them in the HashTbl
	 */
	while( ( DirEntPtr = readdir( DirStream ) ) != NULL )
	{
	    /*
	     * this strcpy() should not be necessary, but ...
	     */
	    strcpy( FileName, DirEntPtr->d_name );

	    if( Insert( DirStream, FileName, H ) == NULL )
		fprintf( stderr, "%s: directory entry not found\n", FileName );
	}

	/*
	 * Print() out your representation of the hash table
	 */
	Print( H );

	/*
	 * now see if you can Find() the files again
	 */
	for( i = 0; Files[ i ] != NULL; i++ )
	    if( ( DirEntPtr = Find( DirStream, Files[ i ], H ) ) != NULL )
		printf( "file /bin/%-5.5s is linked to inode %u\n",
			DirEntPtr->d_name, ( unsigned int )DirEntPtr->d_ino );
	    else
		fprintf( stderr, "%s: directory entry not found\n",
			Files[ i ] );

	/*
	 * close a directory stream
	 */
	( void )closedir( DirStream );
    }
    return EXIT_SUCCESS;
}