dhcpleases.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include <u.h>
#include <libc.h>
#include <bio.h>
#include <ndb.h>
#include <ip.h>
#include <dat.h>

extern	char *binddir;
	long now;
	char *blog = "ipboot";
	int minlease = MinLease;

void
main(void)
{
	Dir *all;
	int i, nall, fd;
	Binding b;

	fmtinstall('E', eipfmt);
	fmtinstall('I', eipfmt);
	fmtinstall('V', eipfmt);
	fmtinstall('M', eipfmt);

	fd = open(binddir, OREAD);
	if(fd < 0)
		sysfatal("opening %s: %r", binddir);
	nall = dirreadall(fd, &all);
	if(nall < 0)
		sysfatal("reading %s: %r", binddir);
	close(fd);

	b.boundto = 0;
	b.lease = b.offer = 0;
	now = time(0);
	for(i = 0; i < nall; i++){
		parseip(b.ip, all[i].name);
		if(syncbinding(&b, 0) < 0)
			continue;
		if(b.lease > now)
			print("%I leased by %s until %s", b.ip, b.boundto, ctime(b.lease));
	}		
}