#include <u.h>#include <libc.h> enum{	Magic= 0x5a5abeef,}; struct {	char *verb;	char *part;	char *file;	int hdr;}method[] ={	{ "k", "/dev/flash/kernel", "/sys/src/9/bitsy/9bitsy", 1 },	{ "r", "/dev/flash/ramdisk", "/sys/src/9/bitsy/ramdisk", 0 },}; voidleputl(uchar *p, ulong x){	*p++ = x;	*p++ = x>>8;	*p++ = x>>16;	*p = x>>24;} voidusage(void){	fprint(2, "usage: %s k|r [file]\n", argv0);	exits("usage");	} voidmain(int argc, char **argv){	char *file;	int ctl, in, out;	int i, n;	uchar *buf;	uchar hdr[12];	char ctlfile[64];	Dir d; 	ARGBEGIN {	} ARGEND; 	if(argc == 0)		usage(); 	for(i = 0; i < nelem(method); i++)		if(strcmp(argv[0], method[i].verb) == 0)			break;	if(i == nelem(method))		usage();	if(argc < 2)		file = method[i].file;	else		file = argv[1]; 	in = open(file, OREAD);	if(in < 0)		sysfatal("%s: %r", file);	if(dirfstat(in, &d) < 0)		sysfatal("stating %s: %r", file); 	/* allocate a buffer and read in the whole file */	n = d.length;	buf = malloc(n+4);	if(buf == nil)		sysfatal("not enough room to read in file: %r");	print("reading %d bytes of %s\n", n, file);	if(readn(in, buf, n) != n)		sysfatal("error reading file: %r");	close(in); 	out = open(method[i].part, OWRITE);	if(out < 0)		sysfatal("%s: %r", method[i].part);	sprint(ctlfile, "%sctl", method[i].part);	ctl = open(ctlfile, OWRITE);	if(ctl < 0)		sysfatal("%s: %r", ctlfile); 	print("erasing %s\n", method[i].part);	if(fprint(ctl, "erase") < 0)		sysfatal("erase %s: %r", ctlfile);	close(ctl);	print("writing %s\n", method[i].part); 	switch(method[i].hdr){	case 1:		leputl(hdr, Magic);		leputl(hdr+4, d.length);		leputl(hdr+8, 0xc0000000);		if(write(out, hdr, 12) != 12)			sysfatal("writing header: %r");		break;	case 0:		leputl(hdr, d.length);		if(write(out, hdr, 4) != 4)			sysfatal("writing header: %r");		break;	} 	if(n & 3)		n += 4-(n&3);	if(write(out, buf, n) != n)		sysfatal("writing %s: %r", file); 	print("write done\n");	close(in);	close(out);}