forked from Imagelibrary/littlefs
1044c9d2b7
I've been scratching my head over our rbyd perturb scheme. It's gotten
rather clunky with needing to xor valid bits and whatnot.
But it's tricky with needing erased-state to be included in parity bits,
while at the same time excluded from our canonical checksum. If only
there was some way to flip the checksums parity without changing its
value...
Enter the crc32c odd-parity zero: 0xfca42daf!
This bends the definition of zero a bit, but it is one of two numbers in
our crc32c-ring with a very interesting property:
crc32c(m) == crc32c(m xor 0xfca42daf) xor 0xfca42daf // odd-p zero
crc32c(m) == crc32c(m xor 0x00000000) xor 0x00000000 // even-p zero
Recall that crc32c's polynomial, 0x11edc6f41, is composed of two
polynomials: 0x3, the parity polynomial, and 0xf5b4253f, a maximally
sized irreducible polynomial. Because our polynomial breaks down into
two smaller polynomials, our crc32c space turns out to not be a field,
but rather a ring containing two smaller sub-fields. Because these
sub-fields are defined by their polynomials, one is the 31-bit crc
defined by the polynomial 0xf5b4253f, while the other is the current
parity.
We can move in the parity sub-field without changing our position in the
31-bit crc sub-field by xoring with a number that is one in the parity
sub-field, but zero in the 31-bit crc sub-field.
This number happens to be 0xf5b4253f (0xfca42daf bit-reversed)!
(crcs being bit-reversed will never not be annoying)
So long story short, xoring any crc32c with 0xfca42daf will change its
parity but not its value.
---
An that's basically our new perturb scheme. If we need to perturb, xor
with 0xfca42daf to change the parity, and after calculating/validating
the checksum, xor with 0xfca42daf to get our canonical checksum.
Isn't that neat!
There was one small hiccup: At first I assumed you could continue
including the valid bits in the checksum, which would have been nice for
bulk checksumming. But this doesn't work because while valid bits cancel
out so the parity doesn't change, changing valid bits _does_ change the
underlying 31-bit crc, poisoning our checksum and making everything a
mess.
So we still need to mask out valid bits, which is a bit annoying.
But then I stumbled on the funny realization that by masking our valid
bits, we accidentally end up with a fully functional parity scheme.
Because valid bits _don't_ include the previous valid bit, we can figure
out the parity for not only the entire commit, but also each individual
tag:
80 03 00 08 6c 69 74 74 6c 65 66 73 80
^'----------------.---------------' ^
| | |
v + parity = v'
Or more simply:
80 03 00 08 6c 69 74 74 6c 65 66 73 80
'----------------.----------------' ^
| |
parity = v'
Double neat!
Some other notes:
- By keeping the commit checksum perturbed, but not the canonical
checksum, the perturb state is self-validating. We no longer need to
explicitly check the previous-perturb-bit (q) to avoid the perturb
hole we ran into previously.
I'm still keeping the previous-perturb-bit (q) around, since it's
useful for debugging. We still need to know the perturb state
internally at all times in order to xor out the canonical checksum
correctly anyways.
- Thanks to all of our perturb iterations, we now know how to remove the
valid bits from the checksum easily:
cksum ^= 0x00000080 & (tag >> 8)
This makes the whole omitting-valid-bits thing less of a pain point.
- It wasn't actually worth it to perturb the checksum when building
commits, vs manually flipping each valid bit, as this would have made
our internal appendattr API really weird.
At least the perturbed checksum made fetch a bit simpler.
Not sure exactly how to draw this with our perturb scheme diagrams,
maybe something like this?
.---+---+---+---. \ \ \ \
|v| tag | | | | |
+---+---+---+---+ | | | |
| commit | | | | |
| | +-. | | |
+---+---+---+---+ / | | | |
|v|qp-------------->p>p-->p .
+---+---+---+---+ | . . .
| cksum | | . . .
+---+---+---+---+ | . . .
| padding | | . . .
| | | . . .
+---+---+---+---+ | | | |
|v------------------' | | |
+---+---+---+---+ | | |
| commit | +-. | +- rbyd
| | | | | | cksum
+---+---+---+---+ / | +-. /
|v----------------------' | |
+-------+---+---+ / |
| cksum ----------------'
+---+---+---+---+
| padding |
| |
+---+---+---+---+
| erased |
| |
. .
. .
---
Code changes were minimal, saving a tiny bit of code:
code stack
before: 36368 2664
after: 36352 (-0.0%) 2672 (+0.3%)
There was a stack bump in lfsr_bd_readtag, but as far as I can tell it's
just compiler noise? I poked around a bit but couldn't figure out why it
changed...
1746 lines
64 KiB
Python
Executable File
1746 lines
64 KiB
Python
Executable File
#!/usr/bin/env python3
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import bisect
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import collections as co
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import itertools as it
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import math as m
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import os
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import struct
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TAG_NULL = 0x0000 ## 0x0000 v--- ---- ---- ----
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TAG_CONFIG = 0x0000 ## 0x00tt v--- ---- -ttt tttt
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TAG_MAGIC = 0x0003 # 0x0003 v--- ---- ---- --11
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TAG_VERSION = 0x0004 # 0x0004 v--- ---- ---- -1--
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TAG_RCOMPAT = 0x0005 # 0x0005 v--- ---- ---- -1-1
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TAG_WCOMPAT = 0x0006 # 0x0006 v--- ---- ---- -11-
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TAG_OCOMPAT = 0x0007 # 0x0007 v--- ---- ---- -111
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TAG_GEOMETRY = 0x0009 # 0x0008 v--- ---- ---- 1-rr
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TAG_NAMELIMIT = 0x000c # 0x000c v--- ---- ---- 11--
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TAG_FILELIMIT = 0x000d # 0x000d v--- ---- ---- 11-1
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TAG_GDELTA = 0x0100 ## 0x01tt v--- ---1 -ttt tttt
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TAG_GRMDELTA = 0x0100 # 0x0100 v--- ---1 ---- ----
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TAG_NAME = 0x0200 ## 0x02tt v--- --1- -ttt tttt
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TAG_REG = 0x0201 # 0x0201 v--- --1- ---- ---1
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TAG_DIR = 0x0202 # 0x0202 v--- --1- ---- --1-
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TAG_BOOKMARK = 0x0204 # 0x0204 v--- --1- ---- -1--
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TAG_ORPHAN = 0x0205 # 0x0205 v--- --1- ---- -1-1
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TAG_STRUCT = 0x0300 ## 0x03tt v--- --11 -ttt tttt
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TAG_DATA = 0x0300 # 0x0300 v--- --11 ---- ----
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TAG_BLOCK = 0x0304 # 0x0304 v--- --11 ---- -1rr
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TAG_BSHRUB = 0x0308 # 0x0308 v--- --11 ---- 1---
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TAG_BTREE = 0x030c # 0x030c v--- --11 ---- 11rr
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TAG_MROOT = 0x0311 # 0x0310 v--- --11 ---1 --rr
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TAG_MDIR = 0x0315 # 0x0314 v--- --11 ---1 -1rr
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TAG_MTREE = 0x031c # 0x031c v--- --11 ---1 11rr
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TAG_DID = 0x0320 # 0x0320 v--- --11 --1- ----
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TAG_BRANCH = 0x032c # 0x032c v--- --11 --1- 11rr
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TAG_UATTR = 0x0400 # 0x04aa v--- -1-a -aaa aaaa
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TAG_SATTR = 0x0600 # 0x06aa v--- -11a -aaa aaaa
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TAG_SHRUB = 0x1000 ## 0x1kkk v--1 kkkk -kkk kkkk
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TAG_ALT = 0x4000 ## 0x4kkk v1cd kkkk -kkk kkkk
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TAG_B = 0x0000
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TAG_R = 0x2000
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TAG_LE = 0x0000
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TAG_GT = 0x1000
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TAG_CKSUM = 0x3000 ## 0x3c0p v-11 cccc ---- --qp
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TAG_P = 0x0001
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TAG_Q = 0x0002
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TAG_NOTE = 0x3100 # 0x3100 v-11 ---1 ---- ----
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TAG_ECKSUM = 0x3200 # 0x3200 v-11 --1- ---- ----
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# some ways of block geometry representations
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# 512 -> 512
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# 512x16 -> (512, 16)
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# 0x200x10 -> (512, 16)
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def bdgeom(s):
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s = s.strip()
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b = 10
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if s.startswith('0x') or s.startswith('0X'):
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s = s[2:]
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b = 16
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elif s.startswith('0o') or s.startswith('0O'):
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s = s[2:]
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b = 8
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elif s.startswith('0b') or s.startswith('0B'):
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s = s[2:]
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b = 2
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if 'x' in s:
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s, s_ = s.split('x', 1)
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return (int(s, b), int(s_, b))
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else:
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return int(s, b)
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# parse some rbyd addr encodings
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# 0xa -> [0xa]
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# 0xa.c -> [(0xa, 0xc)]
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# 0x{a,b} -> [0xa, 0xb]
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# 0x{a,b}.c -> [(0xa, 0xc), (0xb, 0xc)]
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def rbydaddr(s):
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s = s.strip()
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b = 10
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if s.startswith('0x') or s.startswith('0X'):
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s = s[2:]
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b = 16
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elif s.startswith('0o') or s.startswith('0O'):
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s = s[2:]
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b = 8
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elif s.startswith('0b') or s.startswith('0B'):
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s = s[2:]
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b = 2
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trunk = None
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if '.' in s:
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s, s_ = s.split('.', 1)
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trunk = int(s_, b)
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if s.startswith('{') and '}' in s:
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ss = s[1:s.find('}')].split(',')
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else:
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ss = [s]
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addr = []
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for s in ss:
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if trunk is not None:
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addr.append((int(s, b), trunk))
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else:
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addr.append(int(s, b))
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return addr
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def crc32c(data, crc=0):
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crc ^= 0xffffffff
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for b in data:
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crc ^= b
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for j in range(8):
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crc = (crc >> 1) ^ ((crc & 1) * 0x82f63b78)
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return 0xffffffff ^ crc
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def popc(x):
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return bin(x).count('1')
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def parity(x):
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return popc(x) & 1
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def fromle32(data):
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return struct.unpack('<I', data[0:4].ljust(4, b'\0'))[0]
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def fromleb128(data):
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word = 0
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for i, b in enumerate(data):
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word |= ((b & 0x7f) << 7*i)
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word &= 0xffffffff
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if not b & 0x80:
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return word, i+1
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return word, len(data)
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def fromtag(data):
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data = data.ljust(4, b'\0')
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tag = (data[0] << 8) | data[1]
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weight, d = fromleb128(data[2:])
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size, d_ = fromleb128(data[2+d:])
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return tag>>15, tag&0x7fff, weight, size, 2+d+d_
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def frommdir(data):
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blocks = []
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d = 0
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while d < len(data):
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block, d_ = fromleb128(data[d:])
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blocks.append(block)
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d += d_
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return blocks
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def frombranch(data):
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d = 0
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block, d_ = fromleb128(data[d:]); d += d_
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trunk, d_ = fromleb128(data[d:]); d += d_
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cksum = fromle32(data[d:]); d += 4
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return block, trunk, cksum
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def frombtree(data):
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d = 0
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w, d_ = fromleb128(data[d:]); d += d_
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block, trunk, cksum = frombranch(data[d:])
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return w, block, trunk, cksum
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def xxd(data, width=16):
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for i in range(0, len(data), width):
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yield '%-*s %-*s' % (
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3*width,
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' '.join('%02x' % b for b in data[i:i+width]),
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width,
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''.join(
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b if b >= ' ' and b <= '~' else '.'
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for b in map(chr, data[i:i+width])))
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def tagrepr(tag, w=None, size=None, off=None):
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if (tag & 0x6fff) == TAG_NULL:
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return '%snull%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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' w%d' % w if w else '',
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' %d' % size if size else '')
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elif (tag & 0x6f00) == TAG_CONFIG:
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return '%s%s%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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'magic' if (tag & 0xfff) == TAG_MAGIC
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else 'version' if (tag & 0xfff) == TAG_VERSION
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else 'rcompat' if (tag & 0xfff) == TAG_RCOMPAT
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else 'wcompat' if (tag & 0xfff) == TAG_WCOMPAT
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else 'ocompat' if (tag & 0xfff) == TAG_OCOMPAT
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else 'geometry' if (tag & 0xfff) == TAG_GEOMETRY
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else 'namelimit' if (tag & 0xfff) == TAG_NAMELIMIT
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else 'filelimit' if (tag & 0xfff) == TAG_FILELIMIT
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else 'config 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x6f00) == TAG_GDELTA:
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return '%s%s%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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'grmdelta' if (tag & 0xfff) == TAG_GRMDELTA
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else 'gdelta 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x6f00) == TAG_NAME:
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return '%s%s%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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'name' if (tag & 0xfff) == TAG_NAME
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else 'reg' if (tag & 0xfff) == TAG_REG
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else 'dir' if (tag & 0xfff) == TAG_DIR
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else 'orphan' if (tag & 0xfff) == TAG_ORPHAN
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else 'bookmark' if (tag & 0xfff) == TAG_BOOKMARK
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else 'name 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x6f00) == TAG_STRUCT:
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return '%s%s%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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'data' if (tag & 0xfff) == TAG_DATA
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else 'block' if (tag & 0xfff) == TAG_BLOCK
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else 'bshrub' if (tag & 0xfff) == TAG_BSHRUB
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else 'btree' if (tag & 0xfff) == TAG_BTREE
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else 'mroot' if (tag & 0xfff) == TAG_MROOT
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else 'mdir' if (tag & 0xfff) == TAG_MDIR
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else 'mtree' if (tag & 0xfff) == TAG_MTREE
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else 'did' if (tag & 0xfff) == TAG_DID
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else 'branch' if (tag & 0xfff) == TAG_BRANCH
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else 'struct 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x6e00) == TAG_UATTR:
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return '%suattr 0x%02x%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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((tag & 0x100) >> 1) | (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x6e00) == TAG_SATTR:
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return '%ssattr 0x%02x%s%s' % (
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'shrub' if tag & TAG_SHRUB else '',
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((tag & 0x100) >> 1) | (tag & 0xff),
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif tag & TAG_ALT:
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return 'alt%s%s%s%s%s' % (
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'r' if tag & TAG_R else 'b',
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'a' if tag & 0x0fff == 0 and tag & TAG_GT
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else 'n' if tag & 0x0fff == 0
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else 'gt' if tag & TAG_GT
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else 'le',
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' 0x%x' % (tag & 0x0fff) if tag & 0x0fff != 0 else '',
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' w%d' % w if w is not None else '',
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' 0x%x' % (0xffffffff & (off-size))
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if size and off is not None
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else ' -%d' % size if size
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else '')
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elif (tag & 0x7f00) == TAG_CKSUM:
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return 'cksum%s%s%s%s%s' % (
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'q' if not tag & 0xfc and tag & TAG_Q else '',
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'p' if not tag & 0xfc and tag & TAG_P else '',
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' 0x%02x' % (tag & 0xff) if tag & 0xfc else '',
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x7f00) == TAG_NOTE:
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return 'note%s%s%s' % (
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' 0x%02x' % (tag & 0xff) if tag & 0xff else '',
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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elif (tag & 0x7f00) == TAG_ECKSUM:
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return 'ecksum%s%s%s' % (
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' 0x%02x' % (tag & 0xff) if tag & 0xff else '',
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' w%d' % w if w else '',
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' %s' % size if size is not None else '')
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else:
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return '0x%04x%s%s' % (
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tag,
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' w%d' % w if w is not None else '',
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' %d' % size if size is not None else '')
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# this type is used for tree representations
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TBranch = co.namedtuple('TBranch', 'a, b, d, c')
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# our core rbyd type
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class Rbyd:
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def __init__(self, block, data, rev, eoff, trunk, weight, cksum):
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self.block = block
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self.data = data
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self.rev = rev
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self.eoff = eoff
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self.trunk = trunk
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self.weight = weight
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self.cksum = cksum
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self.redund_blocks = []
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def addr(self):
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if not self.redund_blocks:
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return '0x%x.%x' % (self.block, self.trunk)
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else:
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return '0x{%x,%s}.%x' % (
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self.block,
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','.join('%x' % block for block in self.redund_blocks),
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self.trunk)
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@classmethod
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def fetch(cls, f, block_size, blocks, trunk=None):
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if isinstance(blocks, int):
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blocks = [blocks]
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if len(blocks) > 1:
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# fetch all blocks
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rbyds = [cls.fetch(f, block_size, block, trunk) for block in blocks]
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# determine most recent revision
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i = 0
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for i_, rbyd in enumerate(rbyds):
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# compare with sequence arithmetic
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if rbyd and (
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not rbyds[i]
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or not ((rbyd.rev - rbyds[i].rev) & 0x80000000)
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or (rbyd.rev == rbyds[i].rev
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and rbyd.trunk > rbyds[i].trunk)):
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i = i_
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# keep track of the other blocks
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rbyd = rbyds[i]
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rbyd.redund_blocks = [rbyds[(i+1+j) % len(rbyds)].block
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for j in range(len(rbyds)-1)]
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return rbyd
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else:
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# block may encode a trunk
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block = blocks[0]
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if isinstance(block, tuple):
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if trunk is None:
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trunk = block[1]
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block = block[0]
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# seek to the block
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f.seek(block * block_size)
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data = f.read(block_size)
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# fetch the rbyd
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rev = fromle32(data[0:4])
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cksum = 0
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cksum_ = crc32c(data[0:4])
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cksum__ = cksum_
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perturb = False
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eoff = 0
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eoff_ = None
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j_ = 4
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trunk_ = 0
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trunk__ = 0
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trunk___ = 0
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weight = 0
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weight_ = 0
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weight__ = 0
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while j_ < len(data) and (not trunk or eoff <= trunk):
|
|
# read next tag
|
|
v, tag, w, size, d = fromtag(data[j_:])
|
|
if v != parity(cksum__):
|
|
break
|
|
cksum__ ^= 0x00000080 if v else 0
|
|
cksum__ = crc32c(data[j_:j_+d], cksum__)
|
|
j_ += d
|
|
if not tag & TAG_ALT and j_ + size > len(data):
|
|
break
|
|
|
|
# take care of cksums
|
|
if not tag & TAG_ALT:
|
|
if (tag & 0xff00) != TAG_CKSUM:
|
|
cksum__ = crc32c(data[j_:j_+size], cksum__)
|
|
# found a cksum?
|
|
else:
|
|
# check cksum
|
|
cksum___ = fromle32(data[j_:j_+4])
|
|
if cksum__ != cksum___:
|
|
break
|
|
# commit what we have
|
|
eoff = eoff_ if eoff_ else j_ + size
|
|
cksum = cksum_
|
|
trunk_ = trunk__
|
|
weight = weight_
|
|
# update perturb bit
|
|
perturb = tag & TAG_P
|
|
# revert to data cksum and perturb
|
|
cksum__ = cksum_ ^ (0xfca42daf if perturb else 0)
|
|
|
|
# evaluate trunks
|
|
if (tag & 0xf000) != TAG_CKSUM and (
|
|
not trunk or j_-d <= trunk or trunk___):
|
|
# new trunk?
|
|
if not trunk___:
|
|
trunk___ = j_-d
|
|
weight__ = 0
|
|
|
|
# keep track of weight
|
|
weight__ += w
|
|
|
|
# end of trunk?
|
|
if not tag & TAG_ALT:
|
|
# update canonical checksum, xoring out any perturb state
|
|
cksum_ = cksum__ ^ (0xfca42daf if perturb else 0)
|
|
# update trunk/weight unless we found a shrub or an
|
|
# explicit trunk (which may be a shrub) is requested
|
|
if not tag & TAG_SHRUB or trunk___ == trunk:
|
|
trunk__ = trunk___
|
|
weight_ = weight__
|
|
# keep track of eoff for best matching trunk
|
|
if trunk and j_ + size > trunk:
|
|
eoff_ = j_ + size
|
|
eoff = eoff_
|
|
cksum = cksum_
|
|
trunk_ = trunk__
|
|
weight = weight_
|
|
trunk___ = 0
|
|
|
|
if not tag & TAG_ALT:
|
|
j_ += size
|
|
|
|
return cls(block, data, rev, eoff, trunk_, weight, cksum)
|
|
|
|
def lookup(self, rid, tag):
|
|
if not self:
|
|
return True, 0, -1, 0, 0, 0, b'', []
|
|
|
|
tag = max(tag, 0x1)
|
|
lower = 0
|
|
upper = self.weight
|
|
path = []
|
|
|
|
# descend down tree
|
|
j = self.trunk
|
|
while True:
|
|
_, alt, weight_, jump, d = fromtag(self.data[j:])
|
|
|
|
# found an alt?
|
|
if alt & TAG_ALT:
|
|
# follow?
|
|
if ((rid, tag & 0xfff) > (upper-weight_-1, alt & 0xfff)
|
|
if alt & TAG_GT
|
|
else ((rid, tag & 0xfff)
|
|
<= (lower+weight_-1, alt & 0xfff))):
|
|
lower += upper-lower-weight_ if alt & TAG_GT else 0
|
|
upper -= upper-lower-weight_ if not alt & TAG_GT else 0
|
|
j = j - jump
|
|
|
|
# figure out which color
|
|
if alt & TAG_R:
|
|
_, nalt, _, _, _ = fromtag(self.data[j+jump+d:])
|
|
if nalt & TAG_R:
|
|
path.append((j+jump, j, True, 'y'))
|
|
else:
|
|
path.append((j+jump, j, True, 'r'))
|
|
else:
|
|
path.append((j+jump, j, True, 'b'))
|
|
|
|
# stay on path
|
|
else:
|
|
lower += weight_ if not alt & TAG_GT else 0
|
|
upper -= weight_ if alt & TAG_GT else 0
|
|
j = j + d
|
|
|
|
# figure out which color
|
|
if alt & TAG_R:
|
|
_, nalt, _, _, _ = fromtag(self.data[j:])
|
|
if nalt & TAG_R:
|
|
path.append((j-d, j, False, 'y'))
|
|
else:
|
|
path.append((j-d, j, False, 'r'))
|
|
else:
|
|
path.append((j-d, j, False, 'b'))
|
|
|
|
# found tag
|
|
else:
|
|
rid_ = upper-1
|
|
tag_ = alt
|
|
w_ = upper-lower
|
|
|
|
done = not tag_ or (rid_, tag_) < (rid, tag)
|
|
|
|
return done, rid_, tag_, w_, j, d, self.data[j+d:j+d+jump], path
|
|
|
|
def __bool__(self):
|
|
return bool(self.trunk)
|
|
|
|
def __eq__(self, other):
|
|
return self.block == other.block and self.trunk == other.trunk
|
|
|
|
def __ne__(self, other):
|
|
return not self.__eq__(other)
|
|
|
|
def __iter__(self):
|
|
tag = 0
|
|
rid = -1
|
|
|
|
while True:
|
|
done, rid, tag, w, j, d, data, _ = self.lookup(rid, tag+0x1)
|
|
if done:
|
|
break
|
|
|
|
yield rid, tag, w, j, d, data
|
|
|
|
# create tree representation for debugging
|
|
def tree(self, *,
|
|
rbyd=False):
|
|
trunks = co.defaultdict(lambda: (-1, 0))
|
|
alts = co.defaultdict(lambda: {})
|
|
|
|
rid, tag = -1, 0
|
|
while True:
|
|
done, rid, tag, w, j, d, data, path = self.lookup(rid, tag+0x1)
|
|
# found end of tree?
|
|
if done:
|
|
break
|
|
|
|
# keep track of trunks/alts
|
|
trunks[j] = (rid, tag)
|
|
|
|
for j_, j__, followed, c in path:
|
|
if followed:
|
|
alts[j_] |= {'f': j__, 'c': c}
|
|
else:
|
|
alts[j_] |= {'nf': j__, 'c': c}
|
|
|
|
if rbyd:
|
|
# treat unreachable alts as converging paths
|
|
for j_, alt in alts.items():
|
|
if 'f' not in alt:
|
|
alt['f'] = alt['nf']
|
|
elif 'nf' not in alt:
|
|
alt['nf'] = alt['f']
|
|
|
|
else:
|
|
# prune any alts with unreachable edges
|
|
pruned = {}
|
|
for j_, alt in alts.items():
|
|
if 'f' not in alt:
|
|
pruned[j_] = alt['nf']
|
|
elif 'nf' not in alt:
|
|
pruned[j_] = alt['f']
|
|
for j_ in pruned.keys():
|
|
del alts[j_]
|
|
|
|
for j_, alt in alts.items():
|
|
while alt['f'] in pruned:
|
|
alt['f'] = pruned[alt['f']]
|
|
while alt['nf'] in pruned:
|
|
alt['nf'] = pruned[alt['nf']]
|
|
|
|
# find the trunk and depth of each alt
|
|
def rec_trunk(j_):
|
|
if j_ not in alts:
|
|
return trunks[j_]
|
|
else:
|
|
if 'nft' not in alts[j_]:
|
|
alts[j_]['nft'] = rec_trunk(alts[j_]['nf'])
|
|
return alts[j_]['nft']
|
|
|
|
for j_ in alts.keys():
|
|
rec_trunk(j_)
|
|
for j_, alt in alts.items():
|
|
if alt['f'] in alts:
|
|
alt['ft'] = alts[alt['f']]['nft']
|
|
else:
|
|
alt['ft'] = trunks[alt['f']]
|
|
|
|
def rec_height(j_):
|
|
if j_ not in alts:
|
|
return 0
|
|
else:
|
|
if 'h' not in alts[j_]:
|
|
alts[j_]['h'] = max(
|
|
rec_height(alts[j_]['f']),
|
|
rec_height(alts[j_]['nf'])) + 1
|
|
return alts[j_]['h']
|
|
|
|
for j_ in alts.keys():
|
|
rec_height(j_)
|
|
|
|
t_depth = max((alt['h']+1 for alt in alts.values()), default=0)
|
|
|
|
# convert to more general tree representation
|
|
tree = set()
|
|
for j, alt in alts.items():
|
|
# note all non-trunk edges should be black
|
|
tree.add(TBranch(
|
|
a=alt['nft'],
|
|
b=alt['nft'],
|
|
d=t_depth-1 - alt['h'],
|
|
c=alt['c'],
|
|
))
|
|
if alt['ft'] != alt['nft']:
|
|
tree.add(TBranch(
|
|
a=alt['nft'],
|
|
b=alt['ft'],
|
|
d=t_depth-1 - alt['h'],
|
|
c='b',
|
|
))
|
|
|
|
return tree, t_depth
|
|
|
|
# btree lookup with this rbyd as the root
|
|
def btree_lookup(self, f, block_size, bid, *,
|
|
depth=None):
|
|
rbyd = self
|
|
rid = bid
|
|
depth_ = 1
|
|
path = []
|
|
|
|
# corrupted? return a corrupted block once
|
|
if not rbyd:
|
|
return bid > 0, bid, 0, rbyd, -1, [], path
|
|
|
|
while True:
|
|
# collect all tags, normally you don't need to do this
|
|
# but we are debugging here
|
|
name = None
|
|
tags = []
|
|
branch = None
|
|
rid_ = rid
|
|
tag = 0
|
|
w = 0
|
|
for i in it.count():
|
|
done, rid__, tag, w_, j, d, data, _ = rbyd.lookup(
|
|
rid_, tag+0x1)
|
|
if done or (i != 0 and rid__ != rid_):
|
|
break
|
|
|
|
# first tag indicates the branch's weight
|
|
if i == 0:
|
|
rid_, w = rid__, w_
|
|
|
|
# catch any branches
|
|
if tag & 0xfff == TAG_BRANCH:
|
|
branch = (tag, j, d, data)
|
|
|
|
tags.append((tag, j, d, data))
|
|
|
|
# keep track of path
|
|
path.append((bid + (rid_-rid), w, rbyd, rid_, tags))
|
|
|
|
# descend down branch?
|
|
if branch is not None and (
|
|
not depth or depth_ < depth):
|
|
tag, j, d, data = branch
|
|
block, trunk, cksum = frombranch(data)
|
|
rbyd = Rbyd.fetch(f, block_size, block, trunk)
|
|
|
|
# corrupted? bail here so we can keep traversing the tree
|
|
if not rbyd:
|
|
return False, bid + (rid_-rid), w, rbyd, -1, [], path
|
|
|
|
rid -= (rid_-(w-1))
|
|
depth_ += 1
|
|
else:
|
|
return not tags, bid + (rid_-rid), w, rbyd, rid_, tags, path
|
|
|
|
# btree rbyd-tree generation for debugging
|
|
def btree_tree(self, f, block_size, *,
|
|
depth=None,
|
|
inner=False,
|
|
rbyd=False):
|
|
# find the max depth of each layer to nicely align trees
|
|
bdepths = {}
|
|
bid = -1
|
|
while True:
|
|
done, bid, w, rbyd_, rid, tags, path = self.btree_lookup(
|
|
f, block_size, bid+1, depth=depth)
|
|
if done:
|
|
break
|
|
|
|
for d, (bid, w, rbyd_, rid, tags) in enumerate(path):
|
|
_, rdepth = rbyd_.tree(rbyd=rbyd)
|
|
bdepths[d] = max(bdepths.get(d, 0), rdepth)
|
|
|
|
# find all branches
|
|
tree = set()
|
|
root = None
|
|
branches = {}
|
|
bid = -1
|
|
while True:
|
|
done, bid, w, rbyd_, rid, tags, path = self.btree_lookup(
|
|
f, block_size, bid+1, depth=depth)
|
|
if done:
|
|
break
|
|
|
|
d_ = 0
|
|
leaf = None
|
|
for d, (bid, w, rbyd_, rid, tags) in enumerate(path):
|
|
if not tags:
|
|
continue
|
|
|
|
# map rbyd tree into B-tree space
|
|
rtree, rdepth = rbyd_.tree(rbyd=rbyd)
|
|
|
|
# note we adjust our bid/rids to be left-leaning,
|
|
# this allows a global order and make tree rendering quite
|
|
# a bit easier
|
|
rtree_ = set()
|
|
for branch in rtree:
|
|
a_rid, a_tag = branch.a
|
|
b_rid, b_tag = branch.b
|
|
_, _, _, a_w, _, _, _, _ = rbyd_.lookup(a_rid, 0)
|
|
_, _, _, b_w, _, _, _, _ = rbyd_.lookup(b_rid, 0)
|
|
rtree_.add(TBranch(
|
|
a=(a_rid-(a_w-1), a_tag),
|
|
b=(b_rid-(b_w-1), b_tag),
|
|
d=branch.d,
|
|
c=branch.c,
|
|
))
|
|
rtree = rtree_
|
|
|
|
# connect our branch to the rbyd's root
|
|
if leaf is not None:
|
|
root = min(rtree,
|
|
key=lambda branch: branch.d,
|
|
default=None)
|
|
|
|
if root is not None:
|
|
r_rid, r_tag = root.a
|
|
else:
|
|
r_rid, r_tag = rid-(w-1), tags[0][0]
|
|
tree.add(TBranch(
|
|
a=leaf,
|
|
b=(bid-rid+r_rid, d, r_rid, r_tag),
|
|
d=d_-1,
|
|
c='b',
|
|
))
|
|
|
|
for branch in rtree:
|
|
# map rbyd branches into our btree space
|
|
a_rid, a_tag = branch.a
|
|
b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(bid-rid+a_rid, d, a_rid, a_tag),
|
|
b=(bid-rid+b_rid, d, b_rid, b_tag),
|
|
d=branch.d + d_ + bdepths.get(d, 0)-rdepth,
|
|
c=branch.c,
|
|
))
|
|
|
|
d_ += max(bdepths.get(d, 0), 1)
|
|
leaf = (bid-(w-1), d, rid-(w-1),
|
|
next((tag for tag, _, _, _ in tags
|
|
if tag & 0xfff == TAG_BRANCH),
|
|
TAG_BRANCH))
|
|
|
|
# remap branches to leaves if we aren't showing inner branches
|
|
if not inner:
|
|
# step through each layer backwards
|
|
b_depth = max((branch.a[1]+1 for branch in tree), default=0)
|
|
|
|
# keep track of the original bids, unfortunately because we
|
|
# store the bids in the branches we overwrite these
|
|
tree = {(branch.b[0] - branch.b[2], branch) for branch in tree}
|
|
|
|
for bd in reversed(range(b_depth-1)):
|
|
# find leaf-roots at this level
|
|
roots = {}
|
|
for bid, branch in tree:
|
|
# choose the highest node as the root
|
|
if (branch.b[1] == b_depth-1
|
|
and (bid not in roots
|
|
or branch.d < roots[bid].d)):
|
|
roots[bid] = branch
|
|
|
|
# remap branches to leaf-roots
|
|
tree_ = set()
|
|
for bid, branch in tree:
|
|
if branch.a[1] == bd and branch.a[0] in roots:
|
|
branch = TBranch(
|
|
a=roots[branch.a[0]].b,
|
|
b=branch.b,
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
if branch.b[1] == bd and branch.b[0] in roots:
|
|
branch = TBranch(
|
|
a=branch.a,
|
|
b=roots[branch.b[0]].b,
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
tree_.add((bid, branch))
|
|
tree = tree_
|
|
|
|
# strip out bids
|
|
tree = {branch for _, branch in tree}
|
|
|
|
return tree, max((branch.d+1 for branch in tree), default=0)
|
|
|
|
# btree B-tree generation for debugging
|
|
def btree_btree(self, f, block_size, *,
|
|
depth=None,
|
|
inner=False):
|
|
# find all branches
|
|
tree = set()
|
|
root = None
|
|
branches = {}
|
|
bid = -1
|
|
while True:
|
|
done, bid, w, rbyd, rid, tags, path = self.btree_lookup(
|
|
f, block_size, bid+1, depth=depth)
|
|
if done:
|
|
break
|
|
|
|
# if we're not showing inner nodes, prefer names higher in
|
|
# the tree since this avoids showing vestigial names
|
|
name = None
|
|
if not inner:
|
|
name = None
|
|
for bid_, w_, rbyd_, rid_, tags_ in reversed(path):
|
|
for tag_, j_, d_, data_ in tags_:
|
|
if tag_ & 0x7f00 == TAG_NAME:
|
|
name = (tag_, j_, d_, data_)
|
|
|
|
if rid_-(w_-1) != 0:
|
|
break
|
|
|
|
a = root
|
|
for d, (bid, w, rbyd, rid, tags) in enumerate(path):
|
|
if not tags:
|
|
continue
|
|
|
|
b = (bid-(w-1), d, rid-(w-1),
|
|
(name if name else tags[0])[0])
|
|
|
|
# remap branches to leaves if we aren't showing
|
|
# inner branches
|
|
if not inner:
|
|
if b not in branches:
|
|
bid, w, rbyd, rid, tags = path[-1]
|
|
if not tags:
|
|
continue
|
|
branches[b] = (
|
|
bid-(w-1), len(path)-1, rid-(w-1),
|
|
(name if name else tags[0])[0])
|
|
b = branches[b]
|
|
|
|
# found entry point?
|
|
if root is None:
|
|
root = b
|
|
a = root
|
|
|
|
tree.add(TBranch(
|
|
a=a,
|
|
b=b,
|
|
d=d,
|
|
c='b',
|
|
))
|
|
a = b
|
|
|
|
return tree, max((branch.d+1 for branch in tree), default=0)
|
|
|
|
|
|
def main(disk, mroots=None, *,
|
|
block_size=None,
|
|
block_count=None,
|
|
color='auto',
|
|
**args):
|
|
# figure out what color should be
|
|
if color == 'auto':
|
|
color = sys.stdout.isatty()
|
|
elif color == 'always':
|
|
color = True
|
|
else:
|
|
color = False
|
|
|
|
# is bd geometry specified?
|
|
if isinstance(block_size, tuple):
|
|
block_size, block_count_ = block_size
|
|
if block_count is None:
|
|
block_count = block_count_
|
|
|
|
# flatten mroots, default to 0x{0,1}
|
|
if not mroots:
|
|
mroots = [[0,1]]
|
|
mroots = [block for mroots_ in mroots for block in mroots_]
|
|
|
|
# we seek around a bunch, so just keep the disk open
|
|
with open(disk, 'rb') as f:
|
|
# if block_size is omitted, assume the block device is one big block
|
|
if block_size is None:
|
|
f.seek(0, os.SEEK_END)
|
|
block_size = f.tell()
|
|
|
|
# determine the mleaf_weight from the block_size, this is just for
|
|
# printing purposes
|
|
mleaf_weight = 1 << m.ceil(m.log2(block_size // 8))
|
|
|
|
# before we print, we need to do a pass for a few things:
|
|
# - find the actual mroot
|
|
# - find the total weight
|
|
bweight = 0
|
|
rweight = 0
|
|
|
|
mroot = Rbyd.fetch(f, block_size, mroots)
|
|
mdepth = 1
|
|
while True:
|
|
# corrupted?
|
|
if not mroot:
|
|
break
|
|
|
|
rweight = max(rweight, mroot.weight)
|
|
|
|
# stop here?
|
|
if args.get('depth') and mdepth >= args.get('depth'):
|
|
break
|
|
|
|
# fetch the next mroot
|
|
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MROOT)
|
|
if not (not done and rid == -1 and tag == TAG_MROOT):
|
|
break
|
|
|
|
blocks = frommdir(data)
|
|
mroot = Rbyd.fetch(f, block_size, blocks)
|
|
mdepth += 1
|
|
|
|
# fetch the mdir, if there is one
|
|
mdir = None
|
|
if not args.get('depth') or mdepth < args.get('depth'):
|
|
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MDIR)
|
|
if not done and rid == -1 and tag == TAG_MDIR:
|
|
blocks = frommdir(data)
|
|
mdir = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
# corrupted?
|
|
if mdir:
|
|
rweight = max(rweight, mdir.weight)
|
|
|
|
# fetch the actual mtree, if there is one
|
|
mtree = None
|
|
if not args.get('depth') or mdepth < args.get('depth'):
|
|
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MTREE)
|
|
if not done and rid == -1 and tag == TAG_MTREE:
|
|
w, block, trunk, cksum = frombtree(data)
|
|
mtree = Rbyd.fetch(f, block_size, block, trunk)
|
|
|
|
bweight = w
|
|
|
|
# traverse entries
|
|
mbid = -1
|
|
while True:
|
|
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
|
|
f, block_size, mbid+1,
|
|
depth=args.get('depth', mdepth)-mdepth)
|
|
if done:
|
|
break
|
|
|
|
# corrupted?
|
|
if not rbyd:
|
|
continue
|
|
|
|
mdir__ = None
|
|
if (not args.get('depth')
|
|
or mdepth+len(path) < args.get('depth')):
|
|
mdir__ = next(((tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag == TAG_MDIR),
|
|
None)
|
|
|
|
if mdir__:
|
|
# fetch the mdir
|
|
_, _, _, data = mdir__
|
|
blocks = frommdir(data)
|
|
mdir_ = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
# corrupted?
|
|
if mdir_:
|
|
rweight = max(rweight, mdir_.weight)
|
|
|
|
# precompute rbyd-tree if requested
|
|
t_width = 0
|
|
if args.get('tree') or args.get('rbyd'):
|
|
# compute mroot chain "tree", prefix our actual mtree with this
|
|
tree = set()
|
|
d_ = 0
|
|
mroot_ = Rbyd.fetch(f, block_size, mroots)
|
|
mdepth_ = 1
|
|
for d in it.count():
|
|
# corrupted?
|
|
if not mroot_:
|
|
break
|
|
|
|
# compute the mroots rbyd-tree
|
|
rtree, rdepth = mroot_.tree(rbyd=args.get('rbyd'))
|
|
|
|
# connect branch to our root
|
|
if d > 0:
|
|
root = min(rtree,
|
|
key=lambda branch: branch.d,
|
|
default=None)
|
|
|
|
if root:
|
|
r_rid, r_tag = root.a
|
|
else:
|
|
_, r_rid, r_tag, _, _, _, _, _ = mroot_.lookup(-1, 0x1)
|
|
tree.add(TBranch(
|
|
a=(-1, d-1, 0, -1, TAG_MROOT),
|
|
b=(-1, d, 0, r_rid, r_tag),
|
|
d=d_-1,
|
|
c='b',
|
|
))
|
|
|
|
# map the tree into our metadata space
|
|
for branch in rtree:
|
|
a_rid, a_tag = branch.a
|
|
b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(-1, d, 0, a_rid, a_tag),
|
|
b=(-1, d, 0, b_rid, b_tag),
|
|
d=d_ + branch.d,
|
|
c=branch.c,
|
|
))
|
|
d_ += rdepth
|
|
|
|
# stop here?
|
|
if args.get('depth') and mdepth_ >= args.get('depth'):
|
|
break
|
|
|
|
# fetch the next mroot
|
|
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, TAG_MROOT)
|
|
if not (not done and rid == -1 and tag == TAG_MROOT):
|
|
break
|
|
|
|
blocks = frommdir(data)
|
|
mroot_ = Rbyd.fetch(f, block_size, blocks)
|
|
mdepth_ += 1
|
|
|
|
# compute mdir's rbyd-tree if there is one
|
|
if mdir:
|
|
rtree, rdepth = mdir.tree(rbyd=args.get('rbyd'))
|
|
|
|
# connect branch to our root
|
|
root = min(rtree,
|
|
key=lambda branch: branch.d,
|
|
default=None)
|
|
|
|
if root:
|
|
r_rid, r_tag = root.a
|
|
else:
|
|
_, r_rid, r_tag, _, _, _, _, _ = mdir.lookup(-1, 0x1)
|
|
tree.add(TBranch(
|
|
a=(-1, d, 0, -1, TAG_MDIR),
|
|
b=(0, 0, 0, r_rid, r_tag),
|
|
d=d_-1,
|
|
c='b',
|
|
))
|
|
|
|
# map the tree into our metadata space
|
|
for branch in rtree:
|
|
a_rid, a_tag = branch.a
|
|
b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(0, 0, 0, a_rid, a_tag),
|
|
b=(0, 0, 0, b_rid, b_tag),
|
|
d=d_ + branch.d,
|
|
c=branch.c,
|
|
))
|
|
|
|
# compute the mtree's rbyd-tree if there is one
|
|
if mtree:
|
|
tree_, tdepth = mtree.btree_tree(
|
|
f, block_size,
|
|
depth=args.get('depth', mdepth)-mdepth,
|
|
inner=args.get('inner'),
|
|
rbyd=args.get('rbyd'))
|
|
|
|
# connect a branch to the root of the tree
|
|
root = min(tree_, key=lambda branch: branch.d, default=None)
|
|
if root:
|
|
r_bid, r_bd, r_rid, r_tag = root.a
|
|
tree.add(TBranch(
|
|
a=(-1, d, 0, -1, TAG_MTREE),
|
|
b=(r_bid, r_bd, r_rid, 0, r_tag),
|
|
d=d_-1,
|
|
c='b',
|
|
))
|
|
|
|
# map the tree into our metadata space
|
|
for branch in tree_:
|
|
a_bid, a_bd, a_rid, a_tag = branch.a
|
|
b_bid, b_bd, b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(a_bid, a_bd, a_rid, 0, a_tag),
|
|
b=(b_bid, b_bd, b_rid, 0, b_tag),
|
|
d=d_ + branch.d,
|
|
c=branch.c,
|
|
))
|
|
|
|
# find the max depth of each mdir to nicely align trees
|
|
mdepth_ = 0
|
|
mbid = -1
|
|
while True:
|
|
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
|
|
f, block_size, mbid+1,
|
|
depth=args.get('depth', mdepth)-mdepth)
|
|
if done:
|
|
break
|
|
|
|
# corrupted?
|
|
if not rbyd:
|
|
continue
|
|
|
|
mdir__ = None
|
|
if (not args.get('depth')
|
|
or mdepth+len(path) < args.get('depth')):
|
|
mdir__ = next(((tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag == TAG_MDIR),
|
|
None)
|
|
|
|
if mdir__:
|
|
# fetch the mdir
|
|
_, _, _, data = mdir__
|
|
blocks = frommdir(data)
|
|
mdir_ = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
rtree, rdepth = mdir_.tree(rbyd=args.get('rbyd'))
|
|
mdepth_ = max(mdepth_, rdepth)
|
|
|
|
# compute the rbyd-tree for each mdir
|
|
mbid = -1
|
|
while True:
|
|
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
|
|
f, block_size, mbid+1,
|
|
depth=args.get('depth', mdepth)-mdepth)
|
|
if done:
|
|
break
|
|
|
|
# corrupted?
|
|
if not rbyd:
|
|
continue
|
|
|
|
mdir__ = None
|
|
if (not args.get('depth')
|
|
or mdepth+len(path) < args.get('depth')):
|
|
mdir__ = next(((tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag == TAG_MDIR),
|
|
None)
|
|
|
|
if mdir__:
|
|
# fetch the mdir
|
|
_, _, _, data = mdir__
|
|
blocks = frommdir(data)
|
|
mdir_ = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
rtree, rdepth = mdir_.tree(rbyd=args.get('rbyd'))
|
|
|
|
# connect the root to the mtree
|
|
branch = max(
|
|
(branch for branch in tree
|
|
if branch.b[0] == mbid-(mw-1)),
|
|
key=lambda branch: branch.d,
|
|
default=None)
|
|
if branch:
|
|
root = min(rtree,
|
|
key=lambda branch: branch.d,
|
|
default=None)
|
|
if root:
|
|
r_rid, r_tag = root.a
|
|
else:
|
|
_, r_rid, r_tag, _, _, _, _, _ = (
|
|
mdir_.lookup(-1, 0x1))
|
|
tree.add(TBranch(
|
|
a=branch.b,
|
|
b=(mbid-(mw-1), len(path), 0, r_rid, r_tag),
|
|
d=d_ + tdepth,
|
|
c='b',
|
|
))
|
|
|
|
# map the tree into our metadata space
|
|
for branch in rtree:
|
|
a_rid, a_tag = branch.a
|
|
b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(mbid-(mw-1), len(path), 0, a_rid, a_tag),
|
|
b=(mbid-(mw-1), len(path), 0, b_rid, b_tag),
|
|
d=(d_ + tdepth + 1
|
|
+ branch.d + mdepth_-rdepth),
|
|
c=branch.c,
|
|
))
|
|
|
|
# remap branches to leaves if we aren't showing inner branches
|
|
if not args.get('inner'):
|
|
# step through each layer backwards
|
|
b_depth = max((branch.b[1]+1 for branch in tree), default=0)
|
|
|
|
# keep track of the original bids, unfortunately because we
|
|
# store the bids in the branches we overwrite these
|
|
tree = {(branch.b[0] - branch.b[2], branch)
|
|
for branch in tree}
|
|
|
|
for bd in reversed(range(b_depth-1)):
|
|
# find leaf-roots at this level
|
|
roots = {}
|
|
for bid, branch in tree:
|
|
# choose the highest node as the root
|
|
if (branch.b[1] == b_depth-1
|
|
and (bid not in roots
|
|
or branch.d < roots[bid].d)):
|
|
roots[bid] = branch
|
|
|
|
# remap branches to leaf-roots
|
|
tree_ = set()
|
|
for bid, branch in tree:
|
|
# note we ignore mroot branches, we don't collapse
|
|
# normally these
|
|
if (branch.a[0] != -1
|
|
and branch.a[1] == bd
|
|
and branch.a[0] in roots):
|
|
branch = TBranch(
|
|
a=roots[branch.a[0]].b,
|
|
b=branch.b,
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
if (branch.b[0] != -1
|
|
and branch.b[1] == bd
|
|
and branch.b[0] in roots):
|
|
branch = TBranch(
|
|
a=branch.a,
|
|
b=roots[branch.b[0]].b,
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
tree_.add((bid, branch))
|
|
tree = tree_
|
|
|
|
# strip out bids
|
|
tree = {branch for _, branch in tree}
|
|
|
|
# precompute B-tree if requested
|
|
elif args.get('btree'):
|
|
# compute mroot chain "tree", prefix our actual mtree with this
|
|
tree = set()
|
|
mroot_ = Rbyd.fetch(f, block_size, mroots)
|
|
mdepth_ = 1
|
|
for d in it.count():
|
|
# corrupted?
|
|
if not mroot_:
|
|
break
|
|
|
|
# connect branch to our first tag
|
|
if d > 0:
|
|
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, 0x1)
|
|
if not done:
|
|
tree.add(TBranch(
|
|
a=(-1, d-1, 0, -1, TAG_MROOT),
|
|
b=(-1, d, 0, rid, tag),
|
|
d=0,
|
|
c='b',
|
|
))
|
|
|
|
# stop here?
|
|
if args.get('depth') and mdepth_ >= args.get('depth'):
|
|
break
|
|
|
|
# fetch the next mroot
|
|
done, rid, tag, w, j, _, data, _ = mroot_.lookup(-1, TAG_MROOT)
|
|
if not (not done and rid == -1 and tag == TAG_MROOT):
|
|
break
|
|
|
|
blocks = frommdir(data)
|
|
mroot_ = Rbyd.fetch(f, block_size, blocks)
|
|
mdepth_ += 1
|
|
|
|
# create a branch to our mdir if there is one
|
|
if mdir:
|
|
# connect branch to our first tag
|
|
done, rid, tag, w, j, _, data, _ = mdir.lookup(-1, 0x1)
|
|
if not done:
|
|
tree.add(TBranch(
|
|
a=(-1, d, 0, -1, TAG_MDIR),
|
|
b=(0, 0, 0, rid, tag),
|
|
d=0,
|
|
c='b',
|
|
))
|
|
|
|
# compute the mtree's B-tree if there is one
|
|
if mtree:
|
|
tree_, tdepth = mtree.btree_btree(
|
|
f, block_size,
|
|
depth=args.get('depth', mdepth)-mdepth,
|
|
inner=args.get('inner'))
|
|
|
|
# connect a branch to the root of the tree
|
|
root = min(tree_, key=lambda branch: branch.d, default=None)
|
|
if root:
|
|
r_bid, r_bd, r_rid, r_tag = root.a
|
|
tree.add(TBranch(
|
|
a=(-1, d, 0, -1, TAG_MTREE),
|
|
b=(r_bid, r_bd, r_rid, 0, r_tag),
|
|
d=0,
|
|
c='b',
|
|
))
|
|
|
|
# map the tree into our metadata space
|
|
for branch in tree_:
|
|
a_bid, a_bd, a_rid, a_tag = branch.a
|
|
b_bid, b_bd, b_rid, b_tag = branch.b
|
|
tree.add(TBranch(
|
|
a=(a_bid, a_bd, a_rid, 0, a_tag),
|
|
b=(b_bid, b_bd, b_rid, 0, b_tag),
|
|
d=1 + branch.d,
|
|
c=branch.c,
|
|
))
|
|
|
|
# remap branches to leaves if we aren't showing inner branches
|
|
if not args.get('inner'):
|
|
mbid = -1
|
|
while True:
|
|
done, mbid, mw, rbyd, rid, tags, path = (
|
|
mtree.btree_lookup(
|
|
f, block_size, mbid+1,
|
|
depth=args.get('depth', mdepth)-mdepth))
|
|
if done:
|
|
break
|
|
|
|
# corrupted?
|
|
if not rbyd:
|
|
continue
|
|
|
|
mdir__ = None
|
|
if (not args.get('depth')
|
|
or mdepth+len(path) < args.get('depth')):
|
|
mdir__ = next(((tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag == TAG_MDIR),
|
|
None)
|
|
|
|
if mdir__:
|
|
# fetch the mdir
|
|
_, _, _, data = mdir__
|
|
blocks = frommdir(data)
|
|
mdir_ = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
# find the first entry in the mdir, map branches
|
|
# to this entry
|
|
done, rid, tag, _, j, d, data, _ = (
|
|
mdir_.lookup(-1, 0x1))
|
|
|
|
tree_ = set()
|
|
for branch in tree:
|
|
if branch.a[0] == mbid-(mw-1):
|
|
a_bid, a_bd, _, _, _ = branch.a
|
|
branch = TBranch(
|
|
a=(a_bid, a_bd+1, 0, rid, tag),
|
|
b=branch.b,
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
if branch.b[0] == mbid-(mw-1):
|
|
b_bid, b_bd, _, _, _ = branch.b
|
|
branch = TBranch(
|
|
a=branch.a,
|
|
b=(b_bid, b_bd+1, 0, rid, tag),
|
|
d=branch.d,
|
|
c=branch.c,
|
|
)
|
|
tree_.add(branch)
|
|
tree = tree_
|
|
|
|
# common tree renderer
|
|
if args.get('tree') or args.get('rbyd') or args.get('btree'):
|
|
# find the max depth from the tree
|
|
t_depth = max((branch.d+1 for branch in tree), default=0)
|
|
if t_depth > 0:
|
|
t_width = 2*t_depth + 2
|
|
|
|
def treerepr(mbid, mw, md, mrid, rid, tag):
|
|
if t_depth == 0:
|
|
return ''
|
|
|
|
def branchrepr(x, d, was):
|
|
for branch in tree:
|
|
if branch.d == d and branch.b == x:
|
|
if any(branch.d == d and branch.a == x
|
|
for branch in tree):
|
|
return '+-', branch.c, branch.c
|
|
elif any(branch.d == d
|
|
and x > min(branch.a, branch.b)
|
|
and x < max(branch.a, branch.b)
|
|
for branch in tree):
|
|
return '|-', branch.c, branch.c
|
|
elif branch.a < branch.b:
|
|
return '\'-', branch.c, branch.c
|
|
else:
|
|
return '.-', branch.c, branch.c
|
|
for branch in tree:
|
|
if branch.d == d and branch.a == x:
|
|
return '+ ', branch.c, None
|
|
for branch in tree:
|
|
if (branch.d == d
|
|
and x > min(branch.a, branch.b)
|
|
and x < max(branch.a, branch.b)):
|
|
return '| ', branch.c, was
|
|
if was:
|
|
return '--', was, was
|
|
return ' ', None, None
|
|
|
|
trunk = []
|
|
was = None
|
|
for d in range(t_depth):
|
|
t, c, was = branchrepr(
|
|
(mbid-max(mw-1, 0), md, mrid-max(mw-1, 0), rid, tag),
|
|
d, was)
|
|
|
|
trunk.append('%s%s%s%s' % (
|
|
'\x1b[33m' if color and c == 'y'
|
|
else '\x1b[31m' if color and c == 'r'
|
|
else '\x1b[90m' if color and c == 'b'
|
|
else '',
|
|
t,
|
|
('>' if was else ' ') if d == t_depth-1 else '',
|
|
'\x1b[m' if color and c else ''))
|
|
|
|
return '%s ' % ''.join(trunk)
|
|
|
|
|
|
def dbg_mdir(mdir, mbid, mw, md):
|
|
for i, (rid, tag, w, j, d, data) in enumerate(mdir):
|
|
# show human-readable tag representation
|
|
print('%12s %s%s' % (
|
|
'{%s}:' % ','.join('%04x' % block
|
|
for block in it.chain([mdir.block],
|
|
mdir.redund_blocks))
|
|
if i == 0 else '',
|
|
treerepr(mbid-max(mw-1, 0), 0, md, 0, rid, tag)
|
|
if args.get('tree')
|
|
or args.get('rbyd')
|
|
or args.get('btree') else '',
|
|
'%*s %-*s%s' % (
|
|
2*w_width+1, '%d.%d-%d' % (
|
|
mbid//mleaf_weight, rid-(w-1), rid)
|
|
if w > 1 else '%d.%d' % (mbid//mleaf_weight, rid)
|
|
if w > 0 or i == 0 else '',
|
|
21+w_width, tagrepr(tag, w, len(data), j),
|
|
' %s' % next(xxd(data, 8), '')
|
|
if not args.get('raw')
|
|
and not args.get('no_truncate')
|
|
else '')))
|
|
|
|
# show on-disk encoding of tags
|
|
if args.get('raw'):
|
|
for o, line in enumerate(xxd(mdir.data[j:j+d])):
|
|
print('%11s: %*s%*s %s' % (
|
|
'%04x' % (j + o*16),
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
line))
|
|
if args.get('raw') or args.get('no_truncate'):
|
|
if not tag & TAG_ALT:
|
|
for o, line in enumerate(xxd(data)):
|
|
print('%11s: %*s%*s %s' % (
|
|
'%04x' % (j+d + o*16),
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
line))
|
|
|
|
# prbyd here means the last rendered rbyd, we update
|
|
# in dbg_branch to always print interleaved addresses
|
|
prbyd = None
|
|
def dbg_branch(bid, w, rbyd, rid, tags, bd):
|
|
nonlocal prbyd
|
|
|
|
# show human-readable representation
|
|
for i, (tag, j, d, data) in enumerate(tags):
|
|
print('%12s %s%*s %-*s %s' % (
|
|
'%04x.%04x:' % (rbyd.block, rbyd.trunk)
|
|
if prbyd is None or rbyd != prbyd
|
|
else '',
|
|
treerepr(bid, w, bd, rid, 0, tag)
|
|
if args.get('tree')
|
|
or args.get('rbyd')
|
|
or args.get('btree') else '',
|
|
2*w_width+1, '' if i != 0
|
|
else '%d-%d' % (
|
|
(bid-(w-1))//mleaf_weight,
|
|
bid//mleaf_weight)
|
|
if (w//mleaf_weight) > 1
|
|
else bid//mleaf_weight if w > 0
|
|
else '',
|
|
21+w_width, tagrepr(
|
|
tag, w if i == 0 else 0, len(data), None),
|
|
next(xxd(data, 8), '')
|
|
if not args.get('raw') and not args.get('no_truncate')
|
|
else ''))
|
|
prbyd = rbyd
|
|
|
|
# show on-disk encoding of tags/data
|
|
if args.get('raw'):
|
|
for o, line in enumerate(xxd(rbyd.data[j:j+d])):
|
|
print('%11s: %*s%*s %s' % (
|
|
'%04x' % (j + o*16),
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
line))
|
|
if args.get('raw') or args.get('no_truncate'):
|
|
for o, line in enumerate(xxd(data)):
|
|
print('%11s: %*s%*s %s' % (
|
|
'%04x' % (j+d + o*16),
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
line))
|
|
|
|
|
|
#### actual debugging begins here
|
|
|
|
# print some information about the mtree
|
|
print('mtree %s w%d.%d, rev %08x, cksum %08x' % (
|
|
mroot.addr(),
|
|
bweight//mleaf_weight, 1*mleaf_weight,
|
|
mroot.rev,
|
|
mroot.cksum))
|
|
|
|
# dynamically size the id field
|
|
w_width = max(
|
|
m.ceil(m.log10(max(1, bweight//mleaf_weight)+1)),
|
|
m.ceil(m.log10(max(1, rweight)+1)),
|
|
# in case of -1.-1
|
|
2)
|
|
|
|
# show each mroot
|
|
prbyd = None
|
|
ppath = []
|
|
corrupted = False
|
|
mroot = Rbyd.fetch(f, block_size, mroots)
|
|
mdepth = 1
|
|
for d in it.count():
|
|
# corrupted?
|
|
if not mroot:
|
|
print('{%s}: %s%s%s' % (
|
|
','.join('%04x' % block
|
|
for block in it.chain([mroot.block],
|
|
mroot.redund_blocks)),
|
|
'\x1b[31m' if color else '',
|
|
'(corrupted mroot %s)' % mroot.addr(),
|
|
'\x1b[m' if color else ''))
|
|
corrupted = True
|
|
break
|
|
else:
|
|
# show the mdir
|
|
dbg_mdir(mroot, -1, 0, d)
|
|
|
|
# stop here?
|
|
if args.get('depth') and mdepth >= args.get('depth'):
|
|
break
|
|
|
|
# fetch the next mroot
|
|
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MROOT)
|
|
if not (not done and rid == -1 and tag == TAG_MROOT):
|
|
break
|
|
|
|
blocks = frommdir(data)
|
|
mroot = Rbyd.fetch(f, block_size, blocks)
|
|
mdepth += 1
|
|
|
|
# show the mdir, if there is one
|
|
if not args.get('depth') or mdepth < args.get('depth'):
|
|
done, rid, tag, w, j, _, data, _ = mroot.lookup(-1, TAG_MDIR)
|
|
if not done and rid == -1 and tag == TAG_MDIR:
|
|
blocks = frommdir(data)
|
|
mdir = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
# corrupted?
|
|
if not mdir:
|
|
print('{%s}: %s%s%s' % (
|
|
','.join('%04x' % block
|
|
for block in it.chain([mdir.block],
|
|
mdir.redund_blocks)),
|
|
'\x1b[31m' if color else '',
|
|
'(corrupted mdir %s)' % mdir.addr(),
|
|
'\x1b[m' if color else ''))
|
|
corrupted = True
|
|
else:
|
|
# show the mdir
|
|
dbg_mdir(mdir, 0, 0, 0)
|
|
|
|
# fetch the actual mtree, if there is one
|
|
if not args.get('depth') or mdepth < args.get('depth'):
|
|
done, rid, tag, w, j, d, data, _ = mroot.lookup(-1, TAG_MTREE)
|
|
if not done and rid == -1 and tag == TAG_MTREE:
|
|
w, block, trunk, cksum = frombtree(data)
|
|
mtree = Rbyd.fetch(f, block_size, block, trunk)
|
|
|
|
# traverse entries
|
|
mbid = -1
|
|
while True:
|
|
done, mbid, mw, rbyd, rid, tags, path = mtree.btree_lookup(
|
|
f, block_size, mbid+1,
|
|
depth=args.get('depth', mdepth)-mdepth)
|
|
if done:
|
|
break
|
|
|
|
# print inner btree entries if requested
|
|
if args.get('inner'):
|
|
changed = False
|
|
for (x, px) in it.zip_longest(
|
|
enumerate(path[:-1]),
|
|
enumerate(ppath[:-1])):
|
|
if x is None:
|
|
break
|
|
if not (changed or px is None or x != px):
|
|
continue
|
|
changed = True
|
|
|
|
# show the inner entry
|
|
d, (mid_, w_, rbyd_, rid_, tags_) = x
|
|
dbg_branch(mid_, w_, rbyd_, rid_, tags_, d)
|
|
ppath = path
|
|
|
|
# corrupted? try to keep printing the tree
|
|
if not rbyd:
|
|
print('%11s: %*s%s%s%s' % (
|
|
'%04x.%04x' % (rbyd.block, rbyd.trunk),
|
|
t_width, '',
|
|
'\x1b[31m' if color else '',
|
|
'(corrupted rbyd %s)' % rbyd.addr(),
|
|
'\x1b[m' if color else ''))
|
|
prbyd = rbyd
|
|
corrupted = True
|
|
continue
|
|
|
|
# if we're not showing inner nodes, prefer names higher in
|
|
# the tree since this avoids showing vestigial names
|
|
if not args.get('inner'):
|
|
name = None
|
|
for mid_, w_, rbyd_, rid_, tags_ in reversed(path):
|
|
for tag_, j_, d_, data_ in tags_:
|
|
if tag_ & 0x7f00 == TAG_NAME:
|
|
name = (tag_, j_, d_, data_)
|
|
|
|
if rid_-(w_-1) != 0:
|
|
break
|
|
|
|
if name is not None:
|
|
tags = [name] + [(tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag & 0x7f00 != TAG_NAME]
|
|
|
|
# found an mdir in the tags?
|
|
mdir__ = None
|
|
if (not args.get('depth')
|
|
or mdepth+len(path) < args.get('depth')):
|
|
mdir__ = next(((tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag == TAG_MDIR),
|
|
None)
|
|
|
|
# show other btree entries in certain cases
|
|
if args.get('inner') or not mdir__:
|
|
dbg_branch(mbid, mw, rbyd, rid, tags, len(path)-1)
|
|
|
|
if not mdir__:
|
|
continue
|
|
|
|
# fetch the mdir
|
|
_, _, _, data = mdir__
|
|
blocks = frommdir(data)
|
|
mdir_ = Rbyd.fetch(f, block_size, blocks)
|
|
|
|
# corrupted?
|
|
if not mdir_:
|
|
print('{%s}: %*s%s%s%s' % (
|
|
','.join('%04x' % block
|
|
for block in it.chain([mdir_.block],
|
|
mdir_.redund_blocks)),
|
|
t_width, '',
|
|
'\x1b[31m' if color else '',
|
|
'(corrupted mdir %s)' % mdir_.addr(),
|
|
'\x1b[m' if color else ''))
|
|
corrupted = True
|
|
else:
|
|
# show the mdir
|
|
dbg_mdir(mdir_, mbid, mw, len(path))
|
|
|
|
# force next btree entry to be shown
|
|
prbyd = None
|
|
|
|
if args.get('error_on_corrupt') and corrupted:
|
|
sys.exit(2)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import argparse
|
|
import sys
|
|
parser = argparse.ArgumentParser(
|
|
description="Debug littlefs's metadata tree.",
|
|
allow_abbrev=False)
|
|
parser.add_argument(
|
|
'disk',
|
|
help="File containing the block device.")
|
|
parser.add_argument(
|
|
'mroots',
|
|
nargs='*',
|
|
type=rbydaddr,
|
|
help="Block address of the mroots. Defaults to 0x{0,1}.")
|
|
parser.add_argument(
|
|
'-b', '--block-size',
|
|
type=bdgeom,
|
|
help="Block size/geometry in bytes.")
|
|
parser.add_argument(
|
|
'--block-count',
|
|
type=lambda x: int(x, 0),
|
|
help="Block count in blocks.")
|
|
parser.add_argument(
|
|
'--color',
|
|
choices=['never', 'always', 'auto'],
|
|
default='auto',
|
|
help="When to use terminal colors. Defaults to 'auto'.")
|
|
parser.add_argument(
|
|
'-r', '--raw',
|
|
action='store_true',
|
|
help="Show the raw data including tag encodings.")
|
|
parser.add_argument(
|
|
'-T', '--no-truncate',
|
|
action='store_true',
|
|
help="Don't truncate, show the full contents.")
|
|
parser.add_argument(
|
|
'-t', '--tree',
|
|
action='store_true',
|
|
help="Show the underlying rbyd trees.")
|
|
parser.add_argument(
|
|
'-B', '--btree',
|
|
action='store_true',
|
|
help="Show the underlying B-trees.")
|
|
parser.add_argument(
|
|
'-R', '--rbyd',
|
|
action='store_true',
|
|
help="Show the full underlying rbyd trees.")
|
|
parser.add_argument(
|
|
'-i', '--inner',
|
|
action='store_true',
|
|
help="Show inner branches.")
|
|
parser.add_argument(
|
|
'-z', '--depth',
|
|
nargs='?',
|
|
type=lambda x: int(x, 0),
|
|
const=0,
|
|
help="Depth of tree to show.")
|
|
parser.add_argument(
|
|
'-e', '--error-on-corrupt',
|
|
action='store_true',
|
|
help="Error if the filesystem is corrupt.")
|
|
sys.exit(main(**{k: v
|
|
for k, v in vars(parser.parse_intermixed_args()).items()
|
|
if v is not None}))
|