#include	"u.h"#include	"lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h" char *premature = "premature EOF\n"; /* *  read in a segment */static longreadseg(int dev, long (*read)(int, void*, long), long len, long addr){	char *a;	long n, sofar; 	a = (char *)addr;	for(sofar = 0; sofar < len; sofar += n){		n = 8*1024;		if(len - sofar < n)			n = len - sofar;		n = (*read)(dev, a + sofar, n);		if(n <= 0)			break;		print(".");	}	return sofar;} /* *  boot */intplan9boot(int dev, long (*seek)(int, long), long (*read)(int, void*, long)){	long n;	long addr;	void (*b)(void);	Exec *ep; 	if((*seek)(dev, 0) < 0)		return -1; 	/*	 *  read header	 */	ep = (Exec *) ialloc(sizeof(Exec), 0);	n = sizeof(Exec);	if(readseg(dev, read, n, (long) ep) != n){		print(premature);		return -1;	}	if(GLLONG(ep->magic) != Q_MAGIC){		print("bad magic 0x%lux not a plan 9 executable!\n", GLLONG(ep->magic));		return -1;	} 	/*	 *  read text	 */	addr = PADDR(GLLONG(ep->entry));	n = GLLONG(ep->text);	print("%d", n);	if(readseg(dev, read, n, addr) != n){		print(premature);		return -1;	} 	/*	 *  read data (starts at first page after kernel)	 */	addr = PGROUND(addr+n);	n = GLLONG(ep->data);	print("+%d@%8.8lux", n, addr);	if(readseg(dev, read, n, addr) != n){		print(premature);		return -1;	} 	/*	 *  bss and entry point	 */	print("+%d\nstart at 0x%lux\n", GLLONG(ep->bss), GLLONG(ep->entry));	uartwait();	scc2stop();	splhi(); 	/*	 *  Go to new code. It's up to the program to get its PC relocated to	 *  the right place.	 */	b = (void (*)(void))(PADDR(GLLONG(ep->entry)));	(*b)();	return 0;}