/*
	Tabify.c	written by Leor Zolman

	This filter takes sequences of spaces in a file and turns
	them, whenever possible, into tabs. Usage:

		A>tabify oldfile newfile <cr>

	Quoted strings are not processed, but there should NOT be
	any `lone' double quotes within the file being tabified.
*/
/* Changed 6-10-81 CAF newfile optional, eliminated crt list */
/*
 * Changed 8-5-81 CAF Quote terminated at \n
 * This change allows Tabify to be used with .asm files
 */

#include "a:bdscio.h"
#define stdout 1

main(argc,argv)
char **argv;
{
	int scount, column, ifd, ofd, i;
	int lastc, c, tabwidth;
	char	ibuf[BUFSIZ], outfil[BUFSIZ];
	int	*obuf;
	tabwidth= 8;
 	if(argc<2) {
usage:
		puts("usage: tabify [-tabwidth] oldfile [newfile]\n");
		exit();
	}
	if(argv[1][0] == '-'){
		tabwidth = atoi( &argv[1][1]);
		argv++;
		if( --argc <2)
			goto usage;
	}
	else if (!atoi(&argv[1])){
		puts("usage: Use format '-tabwidth' for this option\n");
		exit();
	}
	ifd = fopen(argv[1],ibuf);
	if(argc>2) {
		obuf= outfil;
		ofd = fcreat(argv[2],obuf);
	}
	else {
		obuf=stdout;
		ofd=0;
	}
	if (ifd == ERROR || ofd == ERROR) {
		puts("Can't open file(s)");
		exit();
	}

	scount = column = 0;

	do {
		c = getc(ibuf);
		if (c == ERROR) {
			putc(CPMEOF,obuf);
			break;
		}
		switch(c) {
		case '\n':
			putc1('\r', obuf);
			putc1(c,obuf);
			column = scount = 0;
		case '\r':
			break;
		case ' ':	
			column++;
			scount++;
			if (!(column%tabwidth)) {
				if (scount > 1)
					putc1('\t',obuf);
				else
					putc1(' ',obuf);
				scount = 0;
			}
			break;
		case '\t':	scount = 0;
			column += (tabwidth-column%tabwidth);
			putc1('\t',obuf);
			break;
		case '"':	putc1('"',obuf);
			do {
				lastc=c;
				c = getc(ibuf);
				if (c == ERROR) {
					puts("Quote error.");
					break;
				}
				putc1(c,obuf);
			} while (c != '"' && (c != '\n' || lastc=='\\'));
			while (c != '\n') {
				c = getc(ibuf);
				putc1(c,obuf);
			}
			column = scount = 0;
			break;
		case 0x1a:	putc(CPMEOF,obuf);
			break;
		default:	for (i=0; i<scount; i++)
				putc1(' ',obuf);
			scount = 0;
			column++;
			putc1 (c,obuf);
		}
	} while (c != CPMEOF && c != EOF);

	fflush(ibuf);
	fflush(obuf);
	fclose(ibuf);
	fclose(obuf);
}

putc1(c,buf)
char c;
{
/*
	putchar(c);
*/
	if (putc(c,buf) < 0) {
		puts("putc just retured an error!");
		exit();
	}
}