///FTP CLIENT

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

#include<sys/types.h>
#include<sys/socket.h>
#include<arpa/inet.h>

#include<sys/stat.h>
#include<sys/sendfile.h>
#include<fcntl.h>

int main()
{
	int k,choice;
	int len1,l;
	int counter;
	int sock_desc,filehandle;
	struct sockaddr_in client;
	char buf[100],length[100],fil[100];
	char temp1[100];
	memset(&client,0,sizeof(client));
	sock_desc=socket(AF_INET,SOCK_STREAM,0);
	if(sock_desc==-1)
	{
		puts("Unable to create socket");
		exit(1);
	}

	client.sin_family=AF_INET;
	client.sin_addr.s_addr=INADDR_ANY;
	client.sin_port=8045;

	k=connect(sock_desc,(struct sockaddr *)&client,sizeof(client));
	if(k==-1)
	{
		puts("Error in connect");
		exit(1);
	}
	while(1)
	{
		puts("1.List");
		puts("2.Load");
		puts("3.Store");
		puts("4.EXIT");
		puts("Enter choice:");
		scanf("%d",&choice);
		switch(choice)
		{
		case 1:
			filehandle=open("list2.txt",O_RDWR|O_CREAT,0700);
			strcpy(buf,"LIST");
			k=send(sock_desc,buf,100,0);
			if(k==-1)
			{
				puts("Unable to send");
				exit(1);
			}
			k=recv(sock_desc,length,100,0);
			if(k==-1)
			{
				puts("Error in receive");
				exit(1);
			}
			len1=atoi(length);
			printf("length is %d\n",len1);
			counter=0;
			while(counter<len1)
			{
				l=read(sock_desc,fil,100);
				l=write(filehandle,fil,100);
				counter+=l;
			}
			system("cat list2.txt");
			close(filehandle);
			break;
		case 2:

			filehandle=open("list4.txt",O_RDWR|O_CREAT,0700);
			strcpy(buf,"LOAD ");
			puts("Enter filename:");
			scanf("%s",temp1);
			strcat(buf,temp1);
			k=send(sock_desc,buf,100,0);
			if(k==-1)
			{
				puts("Error in sending");
				exit(1);
			}
			k=recv(sock_desc,length,100,0);
			if(k==-1)
			{
				puts("Error in receiving file");
				exit(1);
			}
			len1=atoi(length);
			printf("Length received:%d\n",len1);
			counter=0;
			strcpy(fil,"");
			while(counter<len1)
			{
				l=read(sock_desc,fil,100);
				l=write(filehandle,fil,100);
				counter+=l;
			}
			system("cat list4.txt");
			break;
		case 3:
		case 4:
			puts("EXITing..");
			break;
		}
	}
	close(sock_desc);
	exit(1);
}


////FTP SERVER WITH TCP

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

#include<sys/types.h>
#include<sys/socket.h>
#include<arpa/inet.h>

#include<sys/stat.h>
#include<sys/sendfile.h>
#include<fcntl.h>


int main()
{
	int sock_desc,sock_desc2;
	socklen_t len;
	struct stat obj;
	char length[10];
	int filehandle;
	char choice[100];
	int k,i;
	char buf[100];
	char target[100];
	struct sockaddr_in client,server;
	memset(&client,0,sizeof(client));
	memset(&server,0,sizeof(server));
	sock_desc=socket(AF_INET,SOCK_STREAM,0);
	if(sock_desc==-1)
	{
		puts("Error in socket 1");
		exit(1);
	}
	server.sin_family=AF_INET;
	server.sin_addr.s_addr=INADDR_ANY;
	server.sin_port=8045;

	k=bind(sock_desc,(struct sockaddr *)&server,sizeof(server));
	if(k==-1)
	{
		puts("Error in binding");
		exit(1);
	}
	k=listen(sock_desc,5);
	if(k==-1)
	{
		puts("Error in listening");
		exit(1);
	}
	len=sizeof(client);
	sock_desc2=accept(sock_desc,(struct sockaddr *)&client,&len);
	if(sock_desc2==-1)
	{
		puts("Error in socket2");
		exit(1);
	}
	while(1)
	{
		k=recv(sock_desc2,buf,100,0);
		if(k==-1)
		{
			puts("Error in receive");
			exit(1);
		}
		for(i=0;i<4;i++)
		{
			choice[i]=buf[i];
		}
		choice[i]='\0';
puts("");
puts(choice);
puts("");
		if(strcmp(choice,"LIST")==0)
		{
		        system("ls -al>list.txt");
		        filehandle=open("list.txt",O_RDONLY);//
        		stat("list.txt",&obj);//
        		sprintf(length,"%d",(int)obj.st_size);
        		puts("sending size of file");
        		k=send(sock_desc2,length,strlen(length),0);
        		if(k==-1)
        		{
        		        printf("send failed");
        		        exit(1);
        		}
        		puts("send entire file");
        		k=sendfile(sock_desc2,filehandle,NULL,obj.st_size);
        		if(k==-1)
        		{
        		        printf("file sendingfailed");
                	exit(1);
       			}

		}
		else if(strcmp(choice,"LOAD")==0)
		{
			puts("inside load");
			strcpy(target,buf+5);
			printf("target file is*%s*\n",target);
			memset(&obj,0,sizeof(obj));
			stat(target,&obj);
			filehandle=open(target,O_RDONLY);
			if(filehandle==-1)
			{
				puts("Error in opening file for read");
				exit(1);
			}
			sprintf(length,"%d",(int)obj.st_size);
			k=send(sock_desc2,length,strlen(length),0);
			if(k==-1)
			{
				puts("Error in sending");
				exit(1);
			}
			k=sendfile(sock_desc2,filehandle,NULL,obj.st_size);
			if(k==-1)
			{
				puts("Error in sending file");
				exit(1);
			}
		}

	}

}