/*

 * Copyright (c) 1990, 1993, 1994, 1995, 1996

 *	The Regents of the University of California.  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that: (1) source code distributions

 * retain the above copyright notice and this paragraph in its entirety, (2)

 * distributions including binary code include the above copyright notice and

 * this paragraph in its entirety in the documentation or other materials

 * provided with the distribution, and (3) all advertising materials mentioning

 * features or use of this software display the following acknowledgement:

 * ``This product includes software developed by the University of California,

 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of

 * the University nor the names of its contributors may be used to endorse

 * or promote products derived from this software without specific prior

 * written permission.

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED

 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <pcap-types.h>

#include <ctype.h>

#include <memory.h>

#include <stdio.h>

#include <string.h>

#include "pcap-int.h"

#include <pcap/namedb.h>

#ifdef HAVE_OS_PROTO_H

#include "os-proto.h"

#endif

static inline int skip_space(FILE *);

static inline int skip_line(FILE *);

/* Hex digit to integer. */

static inline u_char

xdtoi(u_char c)

{

	if (isdigit(c))

		return (u_char)(c - '0');

	else if (islower(c))

		return (u_char)(c - 'a' + 10);

	else

		return (u_char)(c - 'A' + 10);

}

static inline int

skip_space(FILE *f)

{

	int c;

	do {

		c = getc(f);

	} while (isspace(c) && c != '\n');

	return c;

}

static inline int

skip_line(FILE *f)

{

	int c;

	do

		c = getc(f);

	while (c != '\n' && c != EOF);

	return c;

}

struct pcap_etherent *

pcap_next_etherent(FILE *fp)

{

	register int c, i;

	u_char d;

	char *bp;

	size_t namesize;

	static struct pcap_etherent e;

	memset((char *)&e, 0, sizeof(e));

	for (;;) {

		/* Find addr */

		c = skip_space(fp);

		if (c == EOF)

			return (NULL);

		if (c == '\n')

			continue;

		/* If this is a comment, or first thing on line

		   cannot be Ethernet address, skip the line. */

		if (!isxdigit(c)) {

			c = skip_line(fp);

			if (c == EOF)

				return (NULL);

			continue;

		}

		/* must be the start of an address */

		for (i = 0; i < 6; i += 1) {

			d = xdtoi((u_char)c);

			c = getc(fp);

			if (c == EOF)

				return (NULL);

			if (isxdigit(c)) {

				d <<= 4;

				d |= xdtoi((u_char)c);

				c = getc(fp);

				if (c == EOF)

					return (NULL);

			}

			e.addr[i] = d;

			if (c != ':')

				break;

			c = getc(fp);

			if (c == EOF)

				return (NULL);

		}

		/* Must be whitespace */

		if (!isspace(c)) {

			c = skip_line(fp);

			if (c == EOF)

				return (NULL);

			continue;

		}

		c = skip_space(fp);

		if (c == EOF)

			return (NULL);

		/* hit end of line... */

		if (c == '\n')

			continue;

		if (c == '#') {

			c = skip_line(fp);

			if (c == EOF)

				return (NULL);

			continue;

		}

		/* pick up name */

		bp = e.name;

		/* Use 'namesize' to prevent buffer overflow. */

		namesize = sizeof(e.name) - 1;

		do {

			*bp++ = (u_char)c;

			c = getc(fp);

			if (c == EOF)

				return (NULL);

		} while (!isspace(c) && --namesize != 0);

		*bp = '\0';

		/* Eat trailing junk */

		if (c != '\n')

			(void)skip_line(fp);

		return &e;

	}

}