Subversion Repositories planix.SVN

Rev

Rev 2 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2 - 1 
#include <u.h>
2 
#include <libc.h>
3 
#include "flashfs.h"
4 
 
5 
char*	prog;
6 
ulong	sectsize;
7 
ulong	nsects;
8 
uchar*	sectbuff;
9 
int	readonly;
10 
ulong	delta;
11 
int	eparity;
12 
 
13 
uchar	magic[]	= { MAGIC0, MAGIC1, MAGIC2, FFSVERS };
14 
 
15 
int
16 
putc3(uchar *buff, ulong v)
17 
{
18 
	if(v < (1 << 7)) {
19 
		buff[0] = v;
20 
		return 1;
21 
	}
22 
 
23 
	if(v < (1 << 13)) {
24 
		buff[0] = 0x80 | (v >> 7);
25 
		buff[1] = v & ((1 << 7) - 1);
26 
		return 2;
27 
	}
28 
 
29 
	if(v < (1 << 21)) {
30 
		buff[0] = 0x80 | (v >> 15);
31 
		buff[1] = 0x80 | ((v >> 8) & ((1 << 7) - 1));
32 
		buff[2] = v;
33 
		return 3;
34 
	}
35 
 
36 
	fprint(2, "%s: putc3 fail 0x%lux, called from %#p\n", prog, v, getcallerpc(&buff));
37 
	abort();
38 
	return -1;
39 
}
40 
 
41 
int
42 
getc3(uchar *buff, ulong *p)
43 
{
44 
	int c, d;
45 
 
46 
	c = buff[0];
47 
	if((c & 0x80) == 0) {
48 
		*p = c;
49 
		return 1;
50 
	}
51 
 
52 
	c &= ~0x80;
53 
	d = buff[1];
54 
	if((d & 0x80) == 0) {
55 
		*p = (c << 7) | d;
56 
		return 2;
57 
	}
58 
 
59 
	d &= ~0x80;
60 
	*p = (c << 15) | (d << 8) | buff[2];
61 
	return 3;
62 
}
63 
 
64 
ulong
65 
get4(uchar *b)
66 
{
67 
	return	(b[0] <<  0) |
68 
		(b[1] <<  8) |
69 
		(b[2] << 16) |
70 
		(b[3] << 24);
71 
}
72 
 
73 
void
74 
put4(uchar *b, ulong v)
75 
{
76 
	b[0] = v >>  0;
77 
	b[1] = v >>  8;
78 
	b[2] = v >> 16;
79 
	b[3] = v >> 24;
80 
}