#!/usr/bin/icmake -qi

/***************************************************************************

    This file shows an example of a shell around ftp. I use this program a 
lot in situations where I want to transfer a file from one unix host to 
another, and when I know beforehand what file from what directory I want to 
transfer. For the installation:
	- copy this file to your personal bin directory, under the name
	  ftpxfer
	- make the file executable: chmod +x ftpxfer
	
    The program will prompt for the user name and password to use for the 
ftp transfer. If you often access one host with this program, and don't wont 
to type the user/password all the time, you can do the follwing for bash:
	> set FTPUSER my_login_name_on_that_host
	> export FTPUSER
	> set FTPASS my_password_on_that_host
	> export FTPASS
For tcsh, try:
	> setenv FTPUSER my_login_name_on_that_host
	> setenv FTPASS my_password_on_that_host
Net result: this program won't prompt you for the strings, but will retrieve 
them from the environment table. You can, of course, place these commands in 
your .login or .tcshrc file, to be executed automatically during the login 
procedure. But then it may be a good idea to make these files read/write 
only for you and for nobody else (e.g., by: chmod 644 .login).

OB    The actual ftp transfer occurs using an intermediate temporary file, 
TMPFILE in the below #define's. The user name and password _are_ stated in 
that file, but this should not be a security risk. First, the file is 
read/write for the user only, and for no-one else. Second, the file gets 
deleted as soon as it's no longer needed. If you consider this feature still 
a security hazard, take a valium and don't use this program.

*****************************************************************************/

// here's a couple of defines, no need to change them..
#define VER 		"1.02"
#define YEARS 		"1993"

// the following define controls ftp's `verbatim' mode, set it to "-v" 
// if you want verbatim, or to "" if you don't
#define VERBATIM	"-v"

list
    envp;					// environment strings

string
    tmpfile,					// temp file for ftp use
    host,					// host to transfer from/to
    dir,					// foreign directory
    file,					// local file
    direction;					// "get" or "put" file?
    
string getenv (string varname)    		// purpose: returns setting
{						// of environment variable
    int						// 'varname'
    	i;
    	
    for (i = 0; i < sizeof (envp); i += 2)	// loop thru envp...
    	if (element (i, envp) == varname)	// found varname?
    	    return (element (i + 1, envp));	// yes -- return setting
    	    
    return ("");				// no -- return empty string
}

void inittmp ()					// purpose: initialize temp
{						// file

    if (exists (tmpfile))			// remove any old version
    	exec ("rm", tmpfile);			// if it exists
    	
    exec ("touch", tmpfile);			// make empty file
    exec ("chmod", "600", tmpfile);		// make it r/w only for user
}
    
void process ()					// purpose: do the actual 
{						// ftp transfer

    string
    	user,					// user name on foreign host
    	password,				// password
    	foreignfile;				// full name of foreign file
    	
    inittmp ();					// make new temp file

    if (dir)					// if foreign dir specified:
	foreignfile = change_path (file, dir);	// use that
    else if (get_path (file))			// if file spec has its own
    	foreignfile = file;			// directory: keep it
    else					// otherwise: use current
    	foreignfile = change_path (file, 	// directory as dest dir
    	    chdir ("."));
    	    
    if (! (user = getenv ("FTPUSER")) )		// get username from envp
    {						// or prompt for it
    	printf ("User name: ");
    	user = gets ();
    }
    if (! (password = getenv ("FTPASS")) )	// get passwd from envp
    {						// or prompt for it
    	printf ("Password : ");
    	password = gets ();
    }
    
    fprintf (tmpfile, 				// write ftp login procedure
    	"open ", host, "\n",			// to tmpfile, followed
    	"user ", user, " ", password, "\n",	// by transfer commands
    	"binary\n",
    	direction, " ", file, " ", foreignfile, "\n",
    	"quit\n");
    
    exec (P_NOCHECK, "ftp", VERBATIM, 		// do the ftp transfer
        "-n -i", "< ", tmpfile);
    exec (P_NOCHECK, "rm", tmpfile);		// remove temp file
}    
    
void usage ()					// purpose: print usage info
{						// and die
    printf ("\n"
    	    "ICCE Ftp-based File Transfer Shell  V", VER, "\n"
    	    "Copyright (c) ICCE ", YEARS, ". All rights reserved.\n"
    	    "\n"
    	    "Usage: ftpxfer -p|-g host file [directory]\n"
    	    "where:\n"
    	    "       -p         : selects putting of file\n"
    	    "       -g         : selects getting of file\n"
    	    "       host       : host to put/get from/to\n"
    	    "       file       : file to transfer\n"
    	    "       directory  : optional directory at foreign host, if "
						    	    "not given:\n"
	    "                    directory in file argument is used, if not "
	    						    "present:\n"
	    "                    current directory is used for destination\n"
    	    "Ftpxfer will use the environment variables FTPUSER and FTPASS "
    	    						"when available,\n"
	    "or will prompt for the user and password.\n"
    	    "\n");
    exit (1);
}
    
void main (int argc, list argv, list evp)	// main function
{
    envp = evp;					// store environment
    echo (OFF);					// no re-echoing of commands
    tmpfile = "/tmp/ftpxfer." 			// make temporary filename
    	+ (string) getpid ();
    
    if (element (1, argv) == "-p")		// first argument: must
    	direction = "put";			// be -p or -g
    else if (element (1, argv) == "-g")
    	direction = "get";
    else
    	usage ();
    	
    if (! (host = element (2, argv)) )		// second argument: must be
    	usage ();				// foreign host
    if (! (file = element (3, argv)) )		// third argument: must be
    	usage ();				// file to transfer
    if (direction == "put" && ! exists (file))	// if putting: file must
    {						// exist
    	printf ("File to put does not exist.\n");
    	exit (1);
    }    
    
    dir = element (4, argv);			// fourth element: may be 
    						// foreign directory
    
    process ();					// hit it!
    	
    exit (0);					// exitstatus: success
}