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Support fragments and chunks for data

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This commit is contained in:
Vladimir 'phcoder' Serbinenko 2010-12-09 17:06:49 +01:00
parent 7ed6c3e85f
commit 948ebd7e91
1 changed files with 64 additions and 27 deletions
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91
grub-core/fs/squash4.c
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@ -28,16 +28,16 @@
#include <grub/deflate.h> #include <grub/deflate.h>
/* /*
object format Pointed by object format Pointed by
superblock RAW Fixed offset (0) superblock RAW Fixed offset (0)
data RAW ? Fixed offset (60) data RAW ? Fixed offset (60)
inode table Chunk superblock inode table Chunk superblock
dir table Chunk superblock dir table Chunk superblock
unk3 Chunk unk1 fragment table Chunk unk1
unk1 RAW, Chunk superblock unk1 RAW, Chunk superblock
unk2 RAW superblock unk2 RAW superblock
UID/GID Chunk exttblptr UID/GID Chunk exttblptr
exttblptr RAW superblock exttblptr RAW superblock
UID/GID table is the array ot uint32_t UID/GID table is the array ot uint32_t
unk1 contains pointer to unk3 followed by some chunk. unk1 contains pointer to unk3 followed by some chunk.
@ -73,8 +73,8 @@ struct grub_squash_inode
grub_uint16_t dummy1[3]; grub_uint16_t dummy1[3];
grub_uint32_t mtime; grub_uint32_t mtime;
grub_uint16_t dummy2[2]; grub_uint16_t dummy2[2];
grub_uint16_t chunk; grub_uint32_t chunk;
grub_uint16_t dummy3[3]; grub_uint32_t fragment;
grub_uint32_t offset; grub_uint32_t offset;
grub_uint32_t size; grub_uint32_t size;
} __attribute__ ((packed)); } __attribute__ ((packed));
@ -105,10 +105,30 @@ struct grub_squash_dirent
char name[0]; char name[0];
}; };
struct grub_squash_frag_desc
{
grub_uint64_t offset;
grub_uint64_t dummy;
};
#define SQUASH_CHUNK_SIZE 0x2000 #define SQUASH_CHUNK_SIZE 0x2000
#define SQUASH_CHUNK_FLAGS 0x8000 #define SQUASH_CHUNK_FLAGS 0x8000
#define SQUASH_CHUNK_UNCOMPRESSED 0x8000 #define SQUASH_CHUNK_UNCOMPRESSED 0x8000
struct grub_squash_data
{
grub_disk_t disk;
struct grub_squash_super sb;
struct grub_squash_inode ino;
grub_uint64_t fragments;
};
struct grub_fshelp_node
{
struct grub_squash_data *data;
struct grub_squash_inode ino;
};
static grub_err_t static grub_err_t
read_chunk (grub_disk_t disk, void *buf, grub_size_t len, read_chunk (grub_disk_t disk, void *buf, grub_size_t len,
grub_uint64_t chunk, unsigned nchunk, grub_off_t offset) grub_uint64_t chunk, unsigned nchunk, grub_off_t offset)
@ -161,25 +181,13 @@ read_chunk (grub_disk_t disk, void *buf, grub_size_t len,
return GRUB_ERR_NONE; return GRUB_ERR_NONE;
} }
struct grub_squash_data
{
grub_disk_t disk;
struct grub_squash_super sb;
struct grub_squash_inode ino;
};
struct grub_fshelp_node
{
struct grub_squash_data *data;
struct grub_squash_inode ino;
};
static struct grub_squash_data * static struct grub_squash_data *
squash_mount (grub_disk_t disk) squash_mount (grub_disk_t disk)
{ {
struct grub_squash_super sb; struct grub_squash_super sb;
grub_err_t err; grub_err_t err;
struct grub_squash_data *data; struct grub_squash_data *data;
grub_uint64_t frag;
err = grub_disk_read (disk, 0, 0, sizeof (sb), &sb); err = grub_disk_read (disk, 0, 0, sizeof (sb), &sb);
if (grub_errno == GRUB_ERR_OUT_OF_RANGE) if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
@ -191,11 +199,22 @@ squash_mount (grub_disk_t disk)
grub_error (GRUB_ERR_BAD_FS, "not squash4"); grub_error (GRUB_ERR_BAD_FS, "not squash4");
return NULL; return NULL;
} }
err = grub_disk_read (disk, grub_le_to_cpu32 (sb.unk1offset)
>> GRUB_DISK_SECTOR_BITS,
grub_le_to_cpu32 (sb.unk1offset)
& (GRUB_DISK_SECTOR_SIZE - 1), sizeof (frag), &frag);
if (grub_errno == GRUB_ERR_OUT_OF_RANGE)
grub_error (GRUB_ERR_BAD_FS, "not a squash4");
if (err)
return NULL;
data = grub_malloc (sizeof (*data)); data = grub_malloc (sizeof (*data));
if (!data) if (!data)
return NULL; return NULL;
data->sb = sb; data->sb = sb;
data->disk = disk; data->disk = disk;
data->fragments = frag;
return data; return data;
} }
@ -356,6 +375,7 @@ grub_squash_open (struct grub_file *file, const char *name)
file->data = data; file->data = data;
data->ino = fdiro->ino; data->ino = fdiro->ino;
file->size = grub_le_to_cpu32 (fdiro->ino.size); file->size = grub_le_to_cpu32 (fdiro->ino.size);
return GRUB_ERR_NONE; return GRUB_ERR_NONE;
} }
@ -366,8 +386,25 @@ grub_squash_read (grub_file_t file, char *buf, grub_size_t len)
grub_uint64_t a; grub_uint64_t a;
struct grub_squash_data *data = file->data; struct grub_squash_data *data = file->data;
a = sizeof (struct grub_squash_super) + grub_le_to_cpu32 (data->ino.offset) a = grub_le_to_cpu32 (data->ino.offset) + file->offset;
+ file->offset; if (grub_le_to_cpu16 (data->ino.fragment) == 0xffff)
{
if (grub_le_to_cpu32 (data->ino.chunk))
a += grub_le_to_cpu32 (data->ino.chunk);
else
a += sizeof (struct grub_squash_super);
}
else
{
struct grub_squash_frag_desc frag;
err = read_chunk (file->device->disk, &frag, sizeof (frag),
data->fragments, 0, sizeof (frag)
* grub_le_to_cpu16 (data->ino.fragment));
if (err)
return -1;
a += grub_le_to_cpu64 (frag.offset);
a += grub_le_to_cpu32 (data->ino.chunk);
}
err = grub_disk_read (file->device->disk, a >> GRUB_DISK_SECTOR_BITS, err = grub_disk_read (file->device->disk, a >> GRUB_DISK_SECTOR_BITS,
a & (GRUB_DISK_SECTOR_SIZE - 1), len, buf); a & (GRUB_DISK_SECTOR_SIZE - 1), len, buf);