fsrepair.c
1.91 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
#include <PR/bcp.h>
#include "os.h"
#include "os_bbcard.h"
#include "os_bbfs.h"
#include "bbint.h"
s32
osBbFRepairBlock(s32 fd, u32 off, void* buf, u32 len) {
s32 rv, rv2 = 0;
BbInode* in;
u32 b, i, old = 0;
BbFat16* fat;
#ifdef _DEBUG
if ((u32)buf&15) return BBFS_ERR_INVALID;
#endif
if (fd < 0 || fd >= BB_INODE16_ENTRIES) return BBFS_ERR_INVALID;
if ((rv = __osBbFsGetAccess()) < 0) return rv;
fat = __osBbFat;
in = fat->inode+fd;
/* check size, etc */
rv = BBFS_ERR_INVALID;
if (!in->type) goto out;
if ((off & (BB_FL_BLOCK_SIZE-1)) || off >= in->size) goto out;
if (len != BB_FL_BLOCK_SIZE) goto out;
if (off+len < off) goto out; /* overflow */
if (off+len > in->size) goto out;
/* find starting block */
b = in->block;
for(i = 0; i < BB_FL_BYTE_TO_BLOCK(off); i++)
b = BB_FAT16_NEXT(fat,b);
/* paranoia */
if (b == 0 || b >= __osBbFsBlocks-BB_FAT16_BLOCKS) goto out;
if ((rv = osBbCardReadBlock(0, b, buf, 0)) < 0) goto out;
old = b;
retry:
if ((i = __osBbFReallocBlock(in, b, BB_FAT_AVAIL)) == BB_FAT_BAD){
goto error;
}
b = i;
if ((rv = osBbCardEraseBlock(0, b)) < 0 ||
(rv = osBbCardWriteBlock(0, b, buf, 0)) < 0) {
if (rv != BBFS_ERR_FAIL) goto error;
BB_FAT16_NEXT(fat, b) = BB_FAT_BAD;
goto retry;
}
rv = BB_FL_BLOCK_SIZE;
/* change it to be free rather than bad */
old = BB_FAT_BAD; /* magic value for below */
error:
if (old != BB_FAT_BAD && b != old) {
/* failed after reallocating block, put back original block pointer */
BB_FAT16_NEXT(fat,old) = BB_FAT16_NEXT(fat, b);
BB_FAT16_NEXT(fat,b) = BB_FAT_AVAIL;
if (off == 0)
in->block = old;
else {
b = in->block;
for(i = 0; i < BB_FL_BYTE_TO_BLOCK(off)-1; i++)
b = BB_FAT16_NEXT(fat,b);
BB_FAT16_NEXT(fat, b) = old;
}
}
rv2 = __osBbFsSync(0);
out:
__osBbFsRelAccess();
return rv ? rv : rv2;
}