Program to find files with duplicate names using binary search tree

/* Program to find files with duplicate names using binary search tree */

When the hard disk is new the files and directories are properly organized. As the hard disk grows old, some laxity sets in and one tends to create files with duplicate names in different directories. Write a program to locate these duplicate filenames.

#include <stdio.h>
#include <conio.h>
#include <dos.h>
#include <dir.h>
#include <string.h>
#include <alloc.h>

struct btreenode
{
struct btreenode *leftchild ;
char data[13] ; /* file name */
char *loc ; /* location of filename */
struct btreenode *rightchild ;
} *bt = NULL ;

void disktree( ) ;
int insert ( struct btreenode **, char*, char* ) ;

void main( )
{
char current_dir[32] ;

clrscr( ) ;

getcwd ( current_dir, 32 ) ;
chdir ( "\\" ) ;
disktree( ) ;
chdir ( current_dir ) ;

getch( ) ;
}

void disktree( )
{
struct ffblk file ;
int flag ;
char loc[80] ;

getcwd ( loc, 80 ) ;
flag = findfirst ( "*.*", &file, FA_NORMAL | FA_RDONLY | FA_HIDDEN |
FA_SYSTEM | FA_LABEL | FA_DIREC | FA_ARCH ) ;

while ( flag == 0 )
{
if ( file.ff_name[0] != '.' )
{
if ( file.ff_attrib == FA_DIREC && file.ff_fsize == 0 )
{
chdir ( file.ff_name ) ;
disktree( ) ;
chdir ( loc ) ;
}
else
insert ( &bt, loc, file.ff_name ) ;
}
flag = findnext ( &file ) ;
}
}

/* inserts a new node in a binary search tree */
int insert ( struct btreenode **sr, char* l, char* f )
{
char *p ;
int flag ;

if ( *sr == NULL )
{
*sr = ( struct btreenode * ) malloc ( sizeof ( struct btreenode ) ) ;

if ( *sr == NULL )
{
printf ( "\nOut of memory." ) ;
exit ( 1 ) ;
}

( *sr ) -> leftchild = NULL ;
( *sr ) -> rightchild = NULL ;
strcpy ( ( *sr ) -> data, f ) ;
p = ( char * ) malloc ( ( strlen ( l ) + 1 ) ) ;

if ( p == NULL )
{
printf ( "\nOut of memory." ) ;
exit ( 1 ) ;
}

strcpy ( p, l ) ;
( *sr ) -> loc = p ;
}
else
{
flag = strcmp ( ( *sr ) -> data, f ) ;

if ( flag == 0 )
{
printf ( "org: %s", ( *sr ) -> loc ) ;

if ( strlen ( ( *sr ) -> loc ) > 4 )
printf ( "\\" ) ;

printf ( "%s\n", ( *sr ) -> data ) ;
printf ("dup: %s", l ) ;

if ( strlen ( l ) > 4 )
printf ( "\\" ) ;

printf ( "%s\n\n", f ) ;
}
else if ( flag < 0 )
insert ( &( ( *sr ) -> leftchild ), l, f ) ;
else
insert ( &( ( *sr ) -> rightchild ), l, f ) ;
}
return ;
}