forked from Imagelibrary/littlefs
f29a4982c4
Much like the erased-state checksums in our rbyds (ecksums), these
block-level erased-state checksums (becksums) allow us to detect failed
progs to erased parts of a block and are key to achieving efficient
incremental write performance with large blocks and frequent power
cycles/open-close cycles.
These are also key to achieving _reasonable_ write performance for
simple writes (linear, non-overwriting), since littlefs now relies
solely on becksums to efficiently append to blocks.
Though I suppose the previous block staging logic used with the CTZ
skip-list could be brought back to make becksums optional and avoid
btree lookups during simple writes (we do a _lot_ of btree
lookups)... I'll leave this open as a future optimization...
Unlike in-rbyd ecksums, becksums need to be stored out-of-band so our
data blocks only contain raw data. Since they are optional, an
additional tag in the file's btree makes sense.
Becksums are relatively simple, but they bring some challenges:
1. Adding becksums to file btrees is the first case we have for multiple
struct tags per btree id.
This isn't too complicated a problem, but requires some new internal
btree APIs.
Looking forward, which I probably shouldn't be doing this often,
multiple struct tags will also be useful for parity and content ids
as a part of data redundancy and data deduplication, though I think
it's uncontroversial to consider this both heavier-weight features...
2. Becksums only work if unfilled blocks are aligned to the prog_size.
This is the whole point of crystal_size -- to provide temporary
storage for unaligned writes -- but actually aligning the block
during writes turns out to be a bit tricky without a bunch of
unecesssary btree lookups (we already do too many btree lookups!).
The current implementation here discards the pcache to force
alignment, taking advantage of the requirement that
cache_size >= prog_size, but this is corrupting our block checksums.
Code cost:
code stack
before: 31248 2792
after: 32060 (+2.5%) 2864 (+2.5%)
Also lfsr_ftree_flush needs work. I'm usually open to gotos in C when
they improve internal logic, but even for me, the multiple goto jumps
from every left-neighbor lookup into the block writing loop is a bit
much...
1065 lines
36 KiB
Python
Executable File
1065 lines
36 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
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TAG_CONFIG = 0x0000
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TAG_MAGIC = 0x0003
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TAG_VERSION = 0x0004
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TAG_OCOMPATFLAGS = 0x0005
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TAG_RCOMPATFLAGS = 0x0006
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TAG_WCOMPATFLAGS = 0x0007
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TAG_BLOCKSIZE = 0x0008
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TAG_BLOCKCOUNT = 0x0009
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TAG_NAMELIMIT = 0x000a
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TAG_SIZELIMIT = 0x000b
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TAG_GDELTA = 0x0100
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TAG_GRMDELTA = 0x0100
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TAG_NAME = 0x0200
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TAG_REG = 0x0201
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TAG_DIR = 0x0202
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TAG_BOOKMARK = 0x0204
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TAG_STRUCT = 0x0300
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TAG_DATA = 0x0300
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TAG_BLOCK = 0x0304
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TAG_BSHRUB = 0x0308
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TAG_BTREE = 0x030c
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TAG_DID = 0x0310
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TAG_BECKSUM = 0x0314
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TAG_BRANCH = 0x031c
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TAG_MROOT = 0x0321
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TAG_MDIR = 0x0325
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TAG_MTREE = 0x032c
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TAG_UATTR = 0x0400
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TAG_SATTR = 0x0600
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TAG_SHRUB = 0x1000
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TAG_CKSUM = 0x3000
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TAG_ECKSUM = 0x3100
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TAG_ALT = 0x4000
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TAG_GT = 0x2000
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TAG_R = 0x1000
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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 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 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 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, size, off=None):
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if (tag & 0xefff) == 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 & 0xef00) == TAG_CONFIG:
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return '%s%s%s %d' % (
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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 'ocompatflags' if (tag & 0xfff) == TAG_OCOMPATFLAGS
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else 'rcompatflags' if (tag & 0xfff) == TAG_RCOMPATFLAGS
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else 'wcompatflags' if (tag & 0xfff) == TAG_WCOMPATFLAGS
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else 'blocksize' if (tag & 0xfff) == TAG_BLOCKSIZE
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else 'blockcount' if (tag & 0xfff) == TAG_BLOCKCOUNT
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else 'sizelimit' if (tag & 0xfff) == TAG_SIZELIMIT
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else 'namelimit' if (tag & 0xfff) == TAG_NAMELIMIT
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else 'config 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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size)
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elif (tag & 0xef00) == TAG_GDELTA:
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return '%s%s%s %d' % (
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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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size)
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elif (tag & 0xef00) == TAG_NAME:
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return '%s%s%s %d' % (
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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 '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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size)
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elif (tag & 0xef00) == TAG_STRUCT:
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return '%s%s%s %d' % (
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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 'did' if (tag & 0xfff) == TAG_DID
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else 'becksum' if (tag & 0xfff) == TAG_BECKSUM
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else 'branch' if (tag & 0xfff) == TAG_BRANCH
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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 'struct 0x%02x' % (tag & 0xff),
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' w%d' % w if w else '',
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size)
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elif (tag & 0xef00) == TAG_UATTR:
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return '%suattr 0x%02x%s %d' % (
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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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size)
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elif (tag & 0xef00) == TAG_SATTR:
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return '%ssattr 0x%02x%s %d' % (
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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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size)
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elif (tag & 0xff00) == TAG_CKSUM:
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return 'cksum 0x%02x%s %d' % (
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tag & 0xff,
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' w%d' % w if w > 0 else '',
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size)
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elif (tag & 0xff00) == TAG_ECKSUM:
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return 'ecksum%s%s %d' % (
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' 0x%02x' % (tag & 0xff) if tag & 0xff else '',
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' w%d' % w if w > 0 else '',
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size)
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elif tag & TAG_ALT:
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return 'alt%s%s 0x%x w%d %s' % (
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'r' if tag & TAG_R else 'b',
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'gt' if tag & TAG_GT else 'le',
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tag & 0x0fff,
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w,
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'0x%x' % (0xffffffff & (off-size))
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if off is not None
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else '-%d' % off)
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else:
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return '0x%04x w%d %d' % (tag, w, size)
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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):
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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.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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eoff = 0
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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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wastrunk = False
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trunkeoff = None
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while j_ < len(data) and (not trunk or eoff <= trunk):
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v, tag, w, size, d = fromtag(data[j_:])
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if v != (popc(cksum_) & 1):
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break
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cksum_ = crc32c(data[j_:j_+d], cksum_)
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j_ += d
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if not tag & TAG_ALT and j_ + size > len(data):
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break
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# take care of cksums
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if not tag & TAG_ALT:
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if (tag & 0xff00) != TAG_CKSUM:
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cksum_ = crc32c(data[j_:j_+size], cksum_)
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# found a cksum?
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else:
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cksum__ = fromle32(data[j_:j_+4])
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if cksum_ != cksum__:
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break
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# commit what we have
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eoff = trunkeoff if trunkeoff else j_ + size
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cksum = cksum_
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trunk_ = trunk__
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weight = weight_
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# evaluate trunks
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if (tag & 0xf000) != TAG_CKSUM and (
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not trunk or trunk >= j_-d or wastrunk):
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# new trunk?
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if not wastrunk:
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wastrunk = True
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trunk___ = j_-d
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weight__ = 0
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# keep track of weight
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weight__ += w
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# end of trunk?
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if not tag & TAG_ALT:
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wastrunk = False
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# update trunk/weight unless we found a shrub or an
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# explicit trunk (which may be a shrub) is requested
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if not tag & TAG_SHRUB or trunk:
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trunk__ = trunk___
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weight_ = weight__
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# keep track of eoff for best matching trunk
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if trunk and j_ + size > trunk:
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trunkeoff = j_ + size
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cksum = cksum_
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trunk_ = trunk__
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weight = weight_
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if not tag & TAG_ALT:
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j_ += size
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return cls(block, data, rev, eoff, trunk_, weight)
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def lookup(self, rid, tag):
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if not self:
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return True, 0, -1, 0, 0, 0, b'', []
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lower = 0
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upper = self.weight
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path = []
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# descend down tree
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j = self.trunk
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while True:
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_, alt, weight_, jump, d = fromtag(self.data[j:])
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# found an alt?
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if alt & TAG_ALT:
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# follow?
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if ((rid, tag & 0xfff) > (upper-weight_-1, alt & 0xfff)
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if alt & TAG_GT
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else ((rid, tag & 0xfff)
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<= (lower+weight_-1, alt & 0xfff))):
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lower += upper-lower-weight_ if alt & TAG_GT else 0
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upper -= upper-lower-weight_ if not alt & TAG_GT else 0
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j = j - jump
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|
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# figure out which color
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if alt & TAG_R:
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_, nalt, _, _, _ = fromtag(self.data[j+jump+d:])
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if nalt & TAG_R:
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path.append((j+jump, j, True, 'y'))
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else:
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path.append((j+jump, j, True, 'r'))
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else:
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path.append((j+jump, j, True, 'b'))
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|
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# stay on path
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else:
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lower += weight_ if not alt & TAG_GT else 0
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upper -= weight_ if alt & TAG_GT else 0
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j = j + d
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|
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# figure out which color
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if alt & TAG_R:
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_, nalt, _, _, _ = fromtag(self.data[j:])
|
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if nalt & TAG_R:
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path.append((j-d, j, False, 'y'))
|
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else:
|
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path.append((j-d, j, False, 'r'))
|
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else:
|
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path.append((j-d, j, False, 'b'))
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|
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# found tag
|
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else:
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rid_ = upper-1
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tag_ = alt
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w_ = upper-lower
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|
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done = not tag_ or (rid_, tag_) < (rid, tag)
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return done, rid_, tag_, w_, j, d, self.data[j+d:j+d+jump], path
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|
|
def __bool__(self):
|
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return bool(self.trunk)
|
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|
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def __eq__(self, other):
|
|
return self.block == other.block and self.trunk == other.trunk
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|
|
def __ne__(self, other):
|
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return not self.__eq__(other)
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|
|
def __iter__(self):
|
|
tag = 0
|
|
rid = -1
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|
|
|
while True:
|
|
done, rid, tag, w, j, d, data, _ = self.lookup(rid, tag+0x1)
|
|
if done:
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|
break
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|
|
yield rid, tag, w, j, d, data
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|
|
|
# create tree representation for debugging
|
|
def tree(self):
|
|
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}
|
|
|
|
# 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, assuming pruned alts
|
|
# didn't exist
|
|
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'],
|
|
))
|
|
tree.add(TBranch(
|
|
a=alt['nft'],
|
|
b=alt['ft'],
|
|
d=t_depth-1 - alt['h'],
|
|
c='b',
|
|
))
|
|
|
|
return tree, t_depth
|
|
|
|
|
|
def main(disk, roots=None, *,
|
|
block_size=None,
|
|
block_count=None,
|
|
trunk=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 roots, default to block 0
|
|
if not roots:
|
|
roots = [[0]]
|
|
roots = [block for roots_ in roots for block in roots_]
|
|
|
|
# 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()
|
|
|
|
# fetch the root
|
|
btree = Rbyd.fetch(f, block_size, roots, trunk)
|
|
print('btree %s, rev %d, weight %d' % (
|
|
btree.addr(), btree.rev, btree.weight))
|
|
|
|
# look up a bid, while keeping track of the search path
|
|
def btree_lookup(bid, *,
|
|
depth=None):
|
|
rbyd = btree
|
|
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
|
|
|
|
# precompute rbyd-trees if requested
|
|
t_width = 0
|
|
if args.get('tree'):
|
|
# find the max depth of each layer to nicely align trees
|
|
bdepths = {}
|
|
bid = -1
|
|
while True:
|
|
done, bid, w, rbyd, rid, tags, path = btree_lookup(
|
|
bid+1, depth=args.get('depth'))
|
|
if done:
|
|
break
|
|
|
|
for d, (bid, w, rbyd, rid, tags) in enumerate(path):
|
|
_, rdepth = rbyd.tree()
|
|
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 = btree_lookup(
|
|
bid+1, depth=args.get('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()
|
|
|
|
# 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 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:
|
|
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}
|
|
|
|
# precompute B-trees if requested
|
|
elif args.get('btree'):
|
|
# find all branches
|
|
tree = set()
|
|
root = None
|
|
branches = {}
|
|
bid = -1
|
|
while True:
|
|
done, bid, w, rbyd, rid, tags, path = btree_lookup(
|
|
bid+1, depth=args.get('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 args.get('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 args.get('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
|
|
|
|
# common tree renderer
|
|
if args.get('tree') 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(bid, w, bd, 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(
|
|
(bid-(w-1), bd, rid-(w-1), 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)
|
|
|
|
|
|
# dynamically size the id field
|
|
w_width = m.ceil(m.log10(max(1, btree.weight)+1))
|
|
|
|
# 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('%10s %s%*s %-*s %s' % (
|
|
'%04x.%04x:' % (rbyd.block, rbyd.trunk)
|
|
if prbyd is None or rbyd != prbyd
|
|
else '',
|
|
treerepr(bid, w, bd, rid, tag)
|
|
if args.get('tree') or args.get('btree') else '',
|
|
2*w_width+1, '' if i != 0
|
|
else '%d-%d' % (bid-(w-1), bid) if w > 1
|
|
else bid 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 in-device representation
|
|
if args.get('device'):
|
|
print('%9s %*s%*s %04x %08x %07x' % (
|
|
'',
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
tag, w if i == 0 else 0, len(data)))
|
|
|
|
# show on-disk encoding of tags/data
|
|
if args.get('raw'):
|
|
for o, line in enumerate(xxd(rbyd.data[j:j+d])):
|
|
print('%9s: %*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('%9s: %*s%*s %s' % (
|
|
'%04x' % (j+d + o*16),
|
|
t_width, '',
|
|
2*w_width+1, '',
|
|
line))
|
|
|
|
|
|
# traverse and print entries
|
|
bid = -1
|
|
prbyd = None
|
|
ppath = []
|
|
corrupted = False
|
|
while True:
|
|
done, bid, w, rbyd, rid, tags, path = btree_lookup(
|
|
bid+1, depth=args.get('depth'))
|
|
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, (bid_, w_, rbyd_, rid_, tags_) = x
|
|
dbg_branch(bid_, w_, rbyd_, rid_, tags_, d)
|
|
ppath = path
|
|
|
|
# corrupted? try to keep printing the tree
|
|
if not rbyd:
|
|
print('%04x.%04x: %*s%s%s%s' % (
|
|
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 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
|
|
|
|
if name is not None:
|
|
tags = [name] + [(tag, j, d, data)
|
|
for tag, j, d, data in tags
|
|
if tag & 0x7f00 != TAG_NAME]
|
|
|
|
# show the branch
|
|
dbg_branch(bid, w, rbyd, rid, tags, len(path)-1)
|
|
|
|
if args.get('error_on_corrupt') and corrupted:
|
|
sys.exit(2)
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import argparse
|
|
import sys
|
|
parser = argparse.ArgumentParser(
|
|
description="Debug rbyd B-trees.",
|
|
allow_abbrev=False)
|
|
parser.add_argument(
|
|
'disk',
|
|
help="File containing the block device.")
|
|
parser.add_argument(
|
|
'roots',
|
|
nargs='*',
|
|
type=rbydaddr,
|
|
help="Block address of the roots of the tree.")
|
|
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(
|
|
'--trunk',
|
|
type=lambda x: int(x, 0),
|
|
help="Use this offset as the trunk of the tree.")
|
|
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(
|
|
'-x', '--device',
|
|
action='store_true',
|
|
help="Show the device-side representation of tags.")
|
|
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-tree.")
|
|
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 B-tree is corrupt.")
|
|
sys.exit(main(**{k: v
|
|
for k, v in vars(parser.parse_intermixed_args()).items()
|
|
if v is not None}))
|