/*
 * Well, sometimes it's a pain in the ass to have notepad
 * open a text file with "only" character 0x0a on the end
 * of every line. Because notepad for one uses 0x0d 0x0a.
 *
 * This will convert it...
 *
 * -h for help
 *
 * make with:
 *   gcc -o crlf crlf.c
 */

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

#define CRLF2LF 0
#define LF2CRLF 1
#define DEBUG 0

void usage(char * name);

void usage(char * name)
{
		printf("%s will convert lf to cr/lf and the reverse.\n", name);
		printf("Usage: %s [<flag>] < <originalfile> > <newfile>\n", name);
		printf("\nFlags:\n");
		printf("\t-l : CR/LF to LF\n");
		printf("\t-c : LF to CR/LF\n");
		printf("\t-h : This message\n");
		printf("\tDefault is LF to CR/LF\n");
		exit(1);
}

int main(int argc, char * argv[])
{
	int i, opt = LF2CRLF;
	int c;
	char theChar;
	char lf = '\n';
	char cr = '\r';
	
	for(i=1;i<argc;i++) {
		if(argv[i][0] == '-') {
			++argv[i];
			if(strncmp("l", argv[i], 1) == 0)
				opt = CRLF2LF;
			else if(strncmp("c", argv[i], 1) == 0)
				opt = LF2CRLF;
			else if(strncmp("h", argv[i], 1) == 0)
				usage(argv[0]);
		}
	}

#if (DEBUG == 1)
	if(opt == CRLF2LF)
		fprintf(stderr, "CRLF2LF\n");
	if(opt == LF2CRLF)
		fprintf(stderr, "LF2CRLF\n");
#endif
	
	if(opt == LF2CRLF) {
		while( (c = getc(stdin)) != EOF) {
			if(c == 10) {
				fprintf(stdout, "%c", cr);
			}
			fprintf(stdout, "%c", (char)c);
		}
	}

	if(opt == CRLF2LF) {
		while( (c = getc(stdin)) != EOF) {
			theChar = c;
			if(c == 13) {
				if( (c = getc(stdin)) != EOF) {
					if(c == 10) {
						fprintf(stdout, "%c", lf);
					}
					else {
						fprintf(stdout, "%c", (char)c);
					}
				}
			}
			else {
				fprintf(stdout, "%c", (char)c);
			}
		}
	}
	
	return 0;
}