Natty

natty_encrypt.c

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

void natty_encrypt(char *in, char *out) {
	for(int i = 0; in[i]; i++) out[i] = in[i] + i;
}

void natty_decrypt(char *in, char *out) {
	for(int i = 0; in[i]; i++) out[i] = in[i] - i;
}

void doProcess(void (*function)(char *, char *), char *in) {
	char *buf = (void *)0;
	buf = malloc(strlen(in));
	function(in, buf);
	printf("%s\n", buf);
	if(buf != (void *)0) free(buf);
}

int main(int argc, char **argv) {
	if(argc < 3) return 0;
	for(int i = 1; i < argc; i++) {
		if(strcmp(argv[i], "--encrypt") == 0) {
			doProcess(&natty_encrypt, argv[++i]);
			return 0;
		}
		else if(strcmp(argv[i], "--decrypt") == 0) {
			doProcess(&natty_decrypt, argv[++i]);
			return 0;
		}
	}
	return 0;
}