/*
 *  FGETS.C
 *
 *    (c)Copyright 1992-1997 Obvious Implementations Corp.  Redistribution and
 *    use is allowed under the terms of the DICE-LICENSE FILE,
 *    DICE-LICENSE.TXT.
 *
 *  buf = fgets(buf, siz, fi)
 */

#include <stdio.h>

char *
fgets(buf, siz, fi)
char *buf;
int siz;
FILE *fi;
{
    char *base = buf;

    siz -= 2;	/*  room for \n and \0	*/

    /*
     *	do a quick-scan of already-buffered chars to boost efficiency.
     *	Only handles best case.  Note that if RLeft is > 0 then __SIF_READ
     *	must be set so we don't bother to check.
     */

    if (fi && fi->sd_UC < 0 && fi->sd_RLeft > 0) {
	char *ptr = fi->sd_RPtr;
	int i = 0;

	for (i = 0; i < fi->sd_RLeft && i < siz && *ptr != '\n'; ++i)
	    buf[i] = *ptr++;
	if (*ptr == '\n' && i < siz && i < fi->sd_RLeft) {
	    buf[i++] = *ptr;
	    fi->sd_RLeft -= i;
	    fi->sd_RPtr += i;
	    buf[i++] = 0;
	    return(buf);
	}
    }
    if (fi) {
	int cnt = 0;
	int c;

	while ((c = getc(fi)) != EOF) {
	    *buf++ = c;
	    if (c != '\n' && cnt < siz) {
		++cnt;
		continue;
	    }
	    break;
	}
    }
    if (buf == base)
	return(NULL);
    *buf = 0;
    return(base);
}