/* input.c
 * last revised at 16, October, 1995
 *
 * magic input
 * Copyright (C) 1994-5, All rights reserved.
 * written by Gyudong Kim(chilly@iclab.snu.ac.kr)
 *
 */
#include "findhier.h"

static char buf[BUFSIZE];

void seek_char(a, mag)
char a;
FILE *mag;
{
	register int c;

	while ((c = fgetc(mag))!=EOF) {
		if (c==a) return;
	}
}

static int skip_blank(mag)
FILE *mag;
{
	register int c;

	while((c=fgetc(mag))!=EOF) {
		if (!isspace(c)) return(c);
	}
	return(EOF);
}

static void look_for_u(mag)
FILE *mag;
{
	register int c;
	char tmp[3];

	c = skip_blank(mag);
	while(c!=EOF) {
		if (c=='u') {
			if (fgets(tmp,3,mag)==NULL) return;
			if (!strncmp(tmp,"se",2)) return;
		}
		seek_char('\n',mag);
		c = skip_blank(mag);
	}
	return;
}

static char *token(mag)
FILE *mag;
{
	register int c,i;

	i = 0;
	c = skip_blank(mag);
	while (c!=EOF) {
		if (isspace(c)||i>=BUFSIZE-1) {
			buf[i] = 0;
			return(buf);
		}
		buf[i]=c;
		i++;
		c = fgetc(mag);
	}
	buf[i]=0;
	return(buf);
}

/*
 * ignore prefixed spaces
 * determine the first word is "use"
 * if not, ignore.
 * if so, get the next word
 * skip until it reaches an end of line.
 * & return the word
 */
char *getmagline(mag)
FILE *mag;
{
	char *tmp;
	
	look_for_u(mag);
	tmp = token(mag);
	if (tmp[0]) return(tmp);
	return((char *)NULL);
}

/* input.c */