www.pudn.com > encrypttxt.zip > client.c

/* 
 * File:   client.c 
 * Date:   8 May 1999 
 * Author: Bret Taylor (bstaylor@stanford.edu) 
 * ------------------------------------------- 
 * A simple client of the encrypt library.  It simply takes the 
 * names of the input and output files and a key a calls the 
 * library functions to decode/encode. 
 */ 
 
#include  
#include 		/* For tolower() */ 
#include "encrypt.h" 
 
 
/* 
 * Type Definition: bool 
 * --------------------- 
 * A more readable way to represent true/false values.  It relies 
 * on the fact that, in C, all non-zero values are "true" and 0 
 * is "false". 
 */ 
typedef enum { false, true } bool; 
 
 
/* 
 * Main Program 
 * ------------ 
 * This program takes four arguments: 
 *   (1) A "-d" or "-e" switch to indicate "decoding" or "encoding" 
 *   (2) The name of the input file (a text file or, in the case 
 *       of the "-d" switch, a file that has already been encoded). 
 *   (3) The name of the file which the user wants output to be 
 *       to. 
 *   (4) A one-character "key" used for the encoding and decoding 
 *       algorithms. 
 */ 
int main(int argc, char *argv[]) 
{ 
	bool encode; 
	FILE *input, *output; 
 
	if (argc == 5) { 
		encode = (tolower(argv[1][1]) == 'e'); 
	} else { 
		fprintf(stderr, "format: %s [-de] [file name] [output file] [key]\n", argv[0]); 
		return -1; 
	} 
 
	if ((input = fopen(argv[2], "r"))) { 
		if ((output = fopen(argv[3], "w"))) { 
			if (encode) EncodeFile(input, output, argv[4][0]); 
			else DecodeFile(input, output, argv[4][0]); 
		} else { 
			fprintf(stderr, "%s: Unable to open\n", argv[3]); 
		} 
	} else { 
		fprintf(stderr, "%s: File not found\n", argv[2]); 
	} 
 
	return 0; 
}