inet.c

Minix3.11的源码。[MINIX 3是一个为高可靠性应用而设计的自由且简洁的类UNIX系统。]

/*	this file contains the interface of the network software with rest of
	minix. Furthermore it contains the main loop of the network task.

Copyright 1995 Philip Homburg

The valid messages and their parameters are:

from FS:
 __________________________________________________________________
|		|           |         |       |          |         |
| m_type	|   DEVICE  | PROC_NR |	COUNT |	POSITION | ADDRESS |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_OPEN 	| minor dev | proc nr | mode  |          |         |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_CLOSE 	| minor dev | proc nr |       |          |         |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_IOCTL	| minor dev | proc nr |       |	NWIO..	 | address |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_READ	| minor dev | proc nr |	count |          | address |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_WRITE	| minor dev | proc nr |	count |          | address |
|_______________|___________|_________|_______|__________|_________|
|		|           |         |       |          |         |
| NW_CANCEL	| minor dev | proc nr |       |          |         |
|_______________|___________|_________|_______|__________|_________|

from DL_ETH:
 _______________________________________________________________________
|		|           |         |          |            |         |
| m_type	|  DL_PORT  | DL_PROC |	DL_COUNT |  DL_STAT   | DL_TIME |
|_______________|___________|_________|__________|____________|_________|
|		|           |         |          |            |         |
| DL_INIT_REPLY	| minor dev | proc nr | rd_count |  0  | stat |  time   |
|_______________|___________|_________|__________|____________|_________|
|		|           |         |          |            |         |
| DL_TASK_REPLY	| minor dev | proc nr | rd_count | err | stat |  time   |
|_______________|___________|_________|__________|____________|_________|
*/

#include "inet.h"

#define _MINIX_SOURCE 1

#include <fcntl.h>
#include <time.h>
#include <unistd.h>
#include <sys/svrctl.h>

#include "mq.h"
#include "qp.h"
#include "proto.h"
#include "generic/type.h"

#include "generic/arp.h"
#include "generic/assert.h"
#include "generic/buf.h"
#include "generic/clock.h"
#include "generic/eth.h"
#include "generic/event.h"
#include "generic/ip.h"
#include "generic/psip.h"
#include "generic/rand256.h"
#include "generic/sr.h"
#include "generic/tcp.h"
#include "generic/udp.h"

THIS_FILE

#define RANDOM_DEV_NAME	"/dev/random"

int this_proc;		/* Process number of this server. */

#ifdef __minix_vmd
static int synal_tasknr= ANY;
#endif

/* Killing Solaris */
int killer_inet= 0;

#ifdef BUF_CONSISTENCY_CHECK
extern int inet_buf_debug;
#endif

_PROTOTYPE( void main, (void) );

FORWARD _PROTOTYPE( void nw_conf, (void) );
FORWARD _PROTOTYPE( void nw_init, (void) );

PUBLIC void main()
{
	mq_t *mq;
	int r;
	int source, timerand, fd;
	struct fssignon device;
#ifdef __minix_vmd
	struct systaskinfo info;
#endif
	u8_t randbits[32];
	struct timeval tv;

#if DEBUG
	printf("Starting inet...\n");
	printf("%s\n", version);
#endif

	/* Read configuration. */
	nw_conf();

	/* Get a random number */
	timerand= 1;
	fd= open(RANDOM_DEV_NAME, O_RDONLY | O_NONBLOCK);
	if (fd != -1)
	{
		r= read(fd, randbits, sizeof(randbits));
		if (r == sizeof(randbits))
			timerand= 0;
		else
		{
			printf("unable to read random data from %s: %s\n",
				RANDOM_DEV_NAME, r == -1 ? strerror(errno) :
				r == 0 ? "EOF" : "not enough data");
		}
		close(fd);
	}
	else
	{
		printf("unable to open random device %s: %s\n",
			RANDOM_DEV_NAME, strerror(errno));
	}
	if (timerand)
	{
		printf("using current time for random-number seed\n");
#ifdef __minix_vmd
		r= sysutime(UTIME_TIMEOFDAY, &tv);
#else /* Minix 3 */
		r= gettimeofday(&tv, NULL);
#endif
		if (r == -1)
		{
			printf("sysutime failed: %s\n", strerror(errno));
			exit(1);
		}
		memcpy(randbits, &tv, sizeof(tv));
	}
	init_rand256(randbits);

#ifdef __minix_vmd
	if (svrctl(SYSSIGNON, (void *) &info) == -1) pause();

	/* Our new identity as a server. */
	this_proc = info.proc_nr;
#else /* Minix 3 */

	/* Our new identity as a server. */
	if ((this_proc = getprocnr()) < 0)
		ip_panic(( "unable to get own process nr\n"));
#endif

	/* Register the device group. */
	device.dev= ip_dev;
	device.style= STYLE_CLONE;
	if (svrctl(FSSIGNON, (void *) &device) == -1) {
		printf("inet: error %d on registering ethernet devices\n",
			errno);
		pause();
	}

#ifdef BUF_CONSISTENCY_CHECK
	inet_buf_debug= (getenv("inetbufdebug") && 
		(strcmp(getenv("inetbufdebug"), "on") == 0));
	inet_buf_debug= 100;
	if (inet_buf_debug)
	{
		ip_warning(( "buffer consistency check enabled" ));
	}
#endif

	if (getenv("killerinet"))
	{
		ip_warning(( "killer inet active" ));
		killer_inet= 1;
	}

#ifdef __minix_vmd
	r= sys_findproc(SYN_AL_NAME, &synal_tasknr, 0);
	if (r != OK)
		ip_panic(( "unable to find synchronous alarm task: %d\n", r ));
#endif

	nw_init();
	while (TRUE)
	{
#ifdef BUF_CONSISTENCY_CHECK
		if (inet_buf_debug)
		{
			static int buf_debug_count= 0;

			if (++buf_debug_count >= inet_buf_debug)
			{
				buf_debug_count= 0;
				if (!bf_consistency_check())
					break;
			}
		}
#endif
		if (ev_head)
		{
			ev_process();
			continue;
		}
		if (clck_call_expire)
		{
			clck_expire_timers();
			continue;
		}
		mq= mq_get();
		if (!mq)
			ip_panic(("out of messages"));

		r= receive (ANY, &mq->mq_mess);
		if (r<0)
		{
			ip_panic(("unable to receive: %d", r));
		}
		reset_time();
		source= mq->mq_mess.m_source;
		if (source == FS_PROC_NR)
		{
			sr_rec(mq);
		}
#ifdef __minix_vmd
		else if (source == synal_tasknr)
		{
			clck_tick (&mq->mq_mess);
			mq_free(mq);
		}
#else /* Minix 3 */
		else if (mq->mq_mess.m_type == SYN_ALARM)
		{
			clck_tick(&mq->mq_mess);
			mq_free(mq);
		} 
		else if (mq->mq_mess.m_type == SYS_SIG)
		{
			/* signaled */ 
			/* probably SIGTERM */
			mq_free(mq);
		} 
		else if (mq->mq_mess.m_type & NOTIFY_MESSAGE)
		{
			/* A driver is (re)started. */
			eth_check_drivers(&mq->mq_mess);
			mq_free(mq);
		}
#endif
		else
		{
compare(mq->mq_mess.m_type, ==, DL_TASK_REPLY);
			eth_rec(&mq->mq_mess);
			mq_free(mq);
		}
	}
	ip_panic(("task is not allowed to terminate"));
}

PRIVATE void nw_conf()
{
	read_conf();
	eth_prep();
	arp_prep();
	psip_prep();
	ip_prep();
	tcp_prep();
	udp_prep();
}

PRIVATE void nw_init()
{
	mq_init();
	qp_init();
	bf_init();
	clck_init();
	sr_init();
	eth_init();
	arp_init();
	psip_init();
	ip_init();
	tcp_init();
	udp_init();
}

PUBLIC void panic0(file, line)
char *file;
int line;
{
	printf("panic at %s, %d: ", file, line);
}

PUBLIC void inet_panic()
{
	printf("\ninet stacktrace: ");
	stacktrace();
#ifdef __minix_vmd
	sys_abort(RBT_PANIC);
#else /* Minix 3 */
	(panic)("INET","aborted due to a panic",NO_NUM);
#endif
	for(;;);
}

#if !NDEBUG
PUBLIC void bad_assertion(file, line, what)
char *file;
int line;
char *what;
{
	panic0(file, line);
	printf("assertion \"%s\" failed", what);
	panic();
}


PUBLIC void bad_compare(file, line, lhs, what, rhs)
char *file;
int line;
int lhs;
char *what;
int rhs;
{
	panic0(file, line);
	printf("compare (%d) %s (%d) failed", lhs, what, rhs);
	panic();
}
#endif /* !NDEBUG */

/*
 * $PchId: inet.c,v 1.23 2005/06/28 14:27:22 philip Exp $
 */