Files
thirdparty-littlefs/scripts/readtree.py
2020-01-29 01:45:19 -06:00

297 lines
11 KiB
Python
Executable File

#!/usr/bin/env python3
import struct
import sys
import json
import io
import itertools as it
from readmdir import Tag, MetadataPair
def popc(x):
return bin(x).count('1')
def ctz(x):
return len(bin(x)) - len(bin(x).rstrip('0'))
def dumptags(args, mdir, f):
if args.all:
tags = mdir.all_
elif args.log:
tags = mdir.log
else:
tags = mdir.tags
for k, tag in enumerate(tags):
f.write("tag %08x %s" % (tag, tag.typerepr()))
if tag.id != 0x3ff:
f.write(" id %d" % tag.id)
if tag.size != 0x3ff:
f.write(" size %d" % tag.size)
if tag.is_('name'):
f.write(" name %s" %
json.dumps(tag.data.decode('utf8')))
if tag.is_('dirstruct'):
f.write(" dir {%#x, %#x}" % struct.unpack(
'<II', tag.data[:8].ljust(8, b'\xff')))
if tag.is_('ctzstruct'):
f.write(" ctz {%#x} size %d" % struct.unpack(
'<II', tag.data[:8].ljust(8, b'\xff')))
if tag.is_('inlinestruct'):
f.write(" inline size %d" % tag.size)
if tag.is_('gstate'):
f.write(" 0x%s" % ''.join('%02x' % c for c in tag.data))
if tag.is_('tail'):
f.write(" tail {%#x, %#x}" % struct.unpack(
'<II', tag.data[:8].ljust(8, b'\xff')))
f.write("\n")
if args.data:
for i in range(0, len(tag.data), 16):
f.write(" %-47s %-16s\n" % (
' '.join('%02x' % c for c in tag.data[i:i+16]),
''.join(c if c >= ' ' and c <= '~' else '.'
for c in map(chr, tag.data[i:i+16]))))
def dumpentries(args, mdir, f):
for k, id_ in enumerate(mdir.ids):
name = mdir[Tag('name', id_, 0)]
struct_ = mdir[Tag('struct', id_, 0)]
f.write("id %d %s %s" % (
id_, name.typerepr(),
json.dumps(name.data.decode('utf8'))))
if struct_.is_('dirstruct'):
f.write(" dir {%#x, %#x}" % struct.unpack(
'<II', struct_.data[:8].ljust(8, b'\xff')))
if struct_.is_('ctzstruct'):
f.write(" ctz {%#x} size %d" % struct.unpack(
'<II', struct_.data[:8].ljust(8, b'\xff')))
if struct_.is_('inlinestruct'):
f.write(" inline size %d" % struct_.size)
f.write("\n")
if args.data and struct_.is_('inlinestruct'):
for i in range(0, len(struct_.data), 16):
f.write(" %-47s %-16s\n" % (
' '.join('%02x' % c for c in struct_.data[i:i+16]),
''.join(c if c >= ' ' and c <= '~' else '.'
for c in map(chr, struct_.data[i:i+16]))))
elif args.data and struct_.is_('ctzstruct'):
block, size = struct.unpack(
'<II', struct_.data[:8].ljust(8, b'\xff'))
data = []
i = 0 if size == 0 else (size-1) // (args.block_size - 8)
if i != 0:
i = ((size-1) - 4*popc(i-1)+2) // (args.block_size - 8)
with open(args.disk, 'rb') as f2:
while i >= 0:
f2.seek(block * args.block_size)
dat = f2.read(args.block_size)
data.append(dat[4*(ctz(i)+1) if i != 0 else 0:])
block, = struct.unpack('<I', dat[:4].ljust(4, b'\xff'))
i -= 1
data = bytes(it.islice(
it.chain.from_iterable(reversed(data)), size))
for i in range(0, min(len(data), 256)
if not args.no_truncate else len(data), 16):
f.write(" %-47s %-16s\n" % (
' '.join('%02x' % c for c in data[i:i+16]),
''.join(c if c >= ' ' and c <= '~' else '.'
for c in map(chr, data[i:i+16]))))
for tag in mdir.tags:
if tag.id==id_ and tag.is_('userattr'):
f.write("id %d %s size %d\n" % (
id_, tag.typerepr(), tag.size))
if args.data:
for i in range(0, len(tag.data), 16):
f.write(" %-47s %-16s\n" % (
' '.join('%02x' % c for c in tag.data[i:i+16]),
''.join(c if c >= ' ' and c <= '~' else '.'
for c in map(chr, tag.data[i:i+16]))))
def main(args):
with open(args.disk, 'rb') as f:
dirs = []
superblock = None
gstate = b''
mdirs = []
cycle = False
tail = (args.block1, args.block2)
hard = False
while True:
for m in it.chain((m for d in dirs for m in d), mdirs):
if set(m.blocks) == set(tail):
# cycle detected
cycle = m.blocks
if cycle:
break
# load mdir
data = []
blocks = {}
for block in tail:
f.seek(block * args.block_size)
data.append(f.read(args.block_size)
.ljust(args.block_size, b'\xff'))
blocks[id(data[-1])] = block
mdir = MetadataPair(data)
mdir.blocks = tuple(blocks[id(p.data)] for p in mdir.pair)
# fetch some key metadata as a we scan
try:
mdir.tail = mdir[Tag('tail', 0, 0)]
if mdir.tail.size != 8 or mdir.tail.data == 8*b'\xff':
mdir.tail = None
except KeyError:
mdir.tail = None
# have superblock?
try:
nsuperblock = mdir[
Tag(0x7ff, 0x3ff, 0), Tag('superblock', 0, 0)]
superblock = nsuperblock, mdir[Tag('inlinestruct', 0, 0)]
except KeyError:
pass
# have gstate?
try:
ngstate = mdir[Tag('movestate', 0, 0)]
gstate = bytes((a or 0) ^ (b or 0)
for a,b in it.zip_longest(gstate, ngstate.data))
except KeyError:
pass
# add to directories
mdirs.append(mdir)
if mdir.tail is None or not mdir.tail.is_('hardtail'):
dirs.append(mdirs)
mdirs = []
if mdir.tail is None:
break
tail = struct.unpack('<II', mdir.tail.data)
hard = mdir.tail.is_('hardtail')
# find paths
dirtable = {}
for dir in dirs:
dirtable[frozenset(dir[0].blocks)] = dir
pending = [("/", dirs[0])]
while pending:
path, dir = pending.pop(0)
for mdir in dir:
for tag in mdir.tags:
if tag.is_('dir'):
try:
npath = tag.data.decode('utf8')
dirstruct = mdir[Tag('dirstruct', tag.id, 0)]
nblocks = struct.unpack('<II', dirstruct.data)
nmdir = dirtable[frozenset(nblocks)]
pending.append(((path + '/' + npath), nmdir))
except KeyError:
pass
dir[0].path = path.replace('//', '/')
# dump tree
if not args.superblock and not args.gstate and not args.mdirs:
args.superblock = True
args.gstate = True
args.mdirs = True
if args.superblock and superblock:
print("superblock %s v%d.%d" % (
json.dumps(superblock[0].data.decode('utf8')),
struct.unpack('<H', superblock[1].data[2:2+2])[0],
struct.unpack('<H', superblock[1].data[0:0+2])[0]))
print(
" block_size %d\n"
" block_count %d\n"
" name_max %d\n"
" file_max %d\n"
" attr_max %d" % struct.unpack(
'<IIIII', superblock[1].data[4:4+20].ljust(20, b'\xff')))
if args.gstate and gstate:
print("gstate 0x%s" % ''.join('%02x' % c for c in gstate))
tag = Tag(struct.unpack('<I', gstate[0:4].ljust(4, b'\xff'))[0])
blocks = struct.unpack('<II', gstate[4:4+8].ljust(8, b'\xff'))
if tag.size:
print(" orphans %d" % tag.size)
if tag.type:
print(" move dir {%#x, %#x} id %d" % (
blocks[0], blocks[1], tag.id))
if args.mdirs:
for i, dir in enumerate(dirs):
print("dir %s" % (json.dumps(dir[0].path)
if hasattr(dir[0], 'path') else '(orphan)'))
for j, mdir in enumerate(dir):
print("mdir {%#x, %#x} rev %d%s" % (
mdir.blocks[0], mdir.blocks[1], mdir.rev,
' (corrupted)' if not mdir else ''))
f = io.StringIO()
if args.tags or args.all or args.log:
dumptags(args, mdir, f)
else:
dumpentries(args, mdir, f)
lines = list(filter(None, f.getvalue().split('\n')))
for k, line in enumerate(lines):
print("%s %s" % (
' ' if j == len(dir)-1 else
'v' if k == len(lines)-1 else
'|',
line))
if cycle:
print("*** cycle detected! -> {%#x, %#x} ***" % (cycle[0], cycle[1]))
if cycle:
return 2
elif not all(mdir for dir in dirs for mdir in dir):
return 1
else:
return 0;
if __name__ == "__main__":
import argparse
import sys
parser = argparse.ArgumentParser(
description="Dump semantic info about the metadata tree in littlefs")
parser.add_argument('disk',
help="File representing the block device.")
parser.add_argument('block_size', type=lambda x: int(x, 0),
help="Size of a block in bytes.")
parser.add_argument('block1', nargs='?', default=0,
type=lambda x: int(x, 0),
help="Optional first block address for finding the root.")
parser.add_argument('block2', nargs='?', default=1,
type=lambda x: int(x, 0),
help="Optional second block address for finding the root.")
parser.add_argument('-s', '--superblock', action='store_true',
help="Show contents of the superblock.")
parser.add_argument('-g', '--gstate', action='store_true',
help="Show contents of global-state.")
parser.add_argument('-m', '--mdirs', action='store_true',
help="Show contents of metadata-pairs/directories.")
parser.add_argument('-t', '--tags', action='store_true',
help="Show metadata tags instead of reconstructing entries.")
parser.add_argument('-a', '--all', action='store_true',
help="Show all tags in log, included tags in corrupted commits.")
parser.add_argument('-l', '--log', action='store_true',
help="Show tags in log.")
parser.add_argument('-d', '--data', action='store_true',
help="Also show the raw contents of files/attrs/tags.")
parser.add_argument('-T', '--no-truncate', action='store_true',
help="Don't truncate large amounts of data in files.")
sys.exit(main(parser.parse_args()))