inithost.c

来自「TCP-IP红宝书源代码」· C语言 代码 · 共 90 行

/* inithost.c - inithost */

#include <conf.h>
#include <kernel.h>
#include <network.h>

int	efaceinit(int);

#if Noth > 0
static	int	ofaceinit(int), getsim();
static	int	itod[] = { NI_LOCAL, ETHER, OTHER1, OTHER2 };
static	IPaddr	iftoip[] = { {0, 0, 0, 0}, {0, 0, 0, 0},
			{130, 10, 59, 0}, {209, 6, 36, 0} };
#else	/* !(Noth > 0) */
static	int	itod[] = { -1, ETHER };
#endif	/* Noth > 0 */

/*------------------------------------------------------------------------
 * inithost  --  initialize a gateway's interface structures
 *------------------------------------------------------------------------
 */
int
inithost(void)
{
	int	i, host;

	Net.netpool = mkpool(MAXNETBUF, NETBUFS);
	Net.lrgpool = mkpool(MAXLRGBUF, LRGBUFS);
	Net.sema = screate(1);
	Net.nif = NIF;

#if	Noth > 0
	host = getsim();
#endif	/* Noth > 0 */

	for (i=0; i<Net.nif; ++i) {
		/* start with everything 0 */
		memset(&nif[i], 0, sizeof(nif[i]));
		nif[i].ni_state = NIS_DOWN;
		nif[i].ni_ivalid = nif[i].ni_nvalid = FALSE;
		nif[i].ni_svalid = FALSE;
		nif[i].ni_dev = itod[i];
		if (i == NI_LOCAL) {
			/* maxbuf - ether header - CRC - nexthop */
			nif[i].ni_mtu = MAXLRGBUF-EP_HLEN-EP_CRC-IP_ALEN;
			nif[i].ni_ip = ip_anyaddr;
			continue;
		}
		switch(nif[i].ni_dev) {
#ifdef OTHER1
		case OTHER1:
		case OTHER2:
				if (nif[i].ni_dev != host) {
					nif[i].ni_state = NIS_DOWN;
					nif[i].ni_admstate = NIS_DOWN;
					continue;
				}
				ofaceinit(i);
				break;
#endif /* OTHER1 */
		case ETHER:	efaceinit(i);	/* for the simulation */
				nif[i].ni_state = NIS_DOWN;
				nif[i].ni_admstate = NIS_DOWN;
				break;
		};
	}

	return OK;
}

#if Noth > 0
static int
getsim()
{
	char *prompt = "Othernet number? ";
	char *badval = "Choose '1' or '2'.\n";
	char answer[2];

start:
	write(CONSOLE, prompt, strlen(prompt));
	read(CONSOLE, answer, sizeof(answer));
	if (answer[0] == '1' && answer[1] == '\n')
		return OTHER1;
	if (answer[0] == '2' && answer[1] == '\n')
		return OTHER2;
	write(CONSOLE, badval, strlen(badval));
	goto start;
}
#endif /* Noth > 0 */