contrib/linearize/linearize-data.py
#!/usr/bin/env python3
#
# linearize-data.py: Construct a linear, no-fork version of the chain.
#
# Copyright (c) 2013-2022 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
#
import struct
import re
import os
import os.path
import sys
import hashlib
import datetime
import time
import glob
from collections import namedtuple
settings = {}
def calc_hash_str(blk_hdr):
blk_hdr_hash = hashlib.sha256(hashlib.sha256(blk_hdr).digest()).digest()
return blk_hdr_hash[::-1].hex()
def get_blk_dt(blk_hdr):
members = struct.unpack("<I", blk_hdr[68:68+4])
nTime = members[0]
dt = datetime.datetime.fromtimestamp(nTime)
dt_ym = datetime.datetime(dt.year, dt.month, 1)
return (dt_ym, nTime)
# When getting the list of block hashes, undo any byte reversals.
def get_block_hashes(settings):
blkindex = []
with open(settings['hashlist'], "r", encoding="utf8") as f:
for line in f:
line = line.rstrip()
if settings['rev_hash_bytes'] == 'true':
line = bytes.fromhex(line)[::-1].hex()
blkindex.append(line)
print("Read " + str(len(blkindex)) + " hashes")
return blkindex
# The block map shouldn't give or receive byte-reversed hashes.
def mkblockmap(blkindex):
blkmap = {}
for height,hash in enumerate(blkindex):
blkmap[hash] = height
return blkmap
# This gets the first block file ID that exists from the input block
# file directory.
def getFirstBlockFileId(block_dir_path):
# First, this sets up a pattern to search for block files, for
# example 'blkNNNNN.dat'.
blkFilePattern = os.path.join(block_dir_path, "blk[0-9][0-9][0-9][0-9][0-9].dat")
# This search is done with glob
blkFnList = glob.glob(blkFilePattern)
if len(blkFnList) == 0:
print("blocks not pruned - starting at 0")
return 0
# We then get the lexicographic minimum, which should be the first
# block file name.
firstBlkFilePath = min(blkFnList)
firstBlkFn = os.path.basename(firstBlkFilePath)
# now, the string should be ['b','l','k','N','N','N','N','N','.','d','a','t']
# So get the ID by choosing: 3 4 5 6 7
# The ID is not necessarily 0 if this is a pruned node.
blkId = int(firstBlkFn[3:8])
return blkId
# Block header and extent on disk
BlockExtent = namedtuple('BlockExtent', ['fn', 'offset', 'inhdr', 'blkhdr', 'size'])
class BlockDataCopier:
def __init__(self, settings, blkindex, blkmap):
self.settings = settings
self.blkindex = blkindex
self.blkmap = blkmap
# Get first occurring block file id - for pruned nodes this
# will not necessarily be 0
self.inFn = getFirstBlockFileId(self.settings['input'])
self.inF = None
self.outFn = 0
self.outsz = 0
self.outF = None
self.outFname = None
self.blkCountIn = 0
self.blkCountOut = 0
self.lastDate = datetime.datetime(2000, 1, 1)
self.highTS = 1408893517 - 315360000
self.timestampSplit = False
self.fileOutput = True
self.setFileTime = False
self.maxOutSz = settings['max_out_sz']
if 'output' in settings:
self.fileOutput = False
if settings['file_timestamp'] != 0:
self.setFileTime = True
if settings['split_timestamp'] != 0:
self.timestampSplit = True
# Extents and cache for out-of-order blocks
self.blockExtents = {}
self.outOfOrderData = {}
self.outOfOrderSize = 0 # running total size for items in outOfOrderData
def writeBlock(self, inhdr, blk_hdr, rawblock):
blockSizeOnDisk = len(inhdr) + len(blk_hdr) + len(rawblock)
if not self.fileOutput and ((self.outsz + blockSizeOnDisk) > self.maxOutSz):
self.outF.close()
if self.setFileTime:
os.utime(self.outFname, (int(time.time()), self.highTS))
self.outF = None
self.outFname = None
self.outFn = self.outFn + 1
self.outsz = 0
(blkDate, blkTS) = get_blk_dt(blk_hdr)
if self.timestampSplit and (blkDate > self.lastDate):
print("New month " + blkDate.strftime("%Y-%m") + " @ " + self.hash_str)
self.lastDate = blkDate
if self.outF:
self.outF.close()
if self.setFileTime:
os.utime(self.outFname, (int(time.time()), self.highTS))
self.outF = None
self.outFname = None
self.outFn = self.outFn + 1
self.outsz = 0
if not self.outF:
if self.fileOutput:
self.outFname = self.settings['output_file']
else:
self.outFname = os.path.join(self.settings['output'], "blk%05d.dat" % self.outFn)
print("Output file " + self.outFname)
self.outF = open(self.outFname, "wb")
self.outF.write(inhdr)
self.outF.write(blk_hdr)
self.outF.write(rawblock)
self.outsz = self.outsz + len(inhdr) + len(blk_hdr) + len(rawblock)
self.blkCountOut = self.blkCountOut + 1
if blkTS > self.highTS:
self.highTS = blkTS
if (self.blkCountOut % 1000) == 0:
print('%i blocks scanned, %i blocks written (of %i, %.1f%% complete)' %
(self.blkCountIn, self.blkCountOut, len(self.blkindex), 100.0 * self.blkCountOut / len(self.blkindex)))
def inFileName(self, fn):
return os.path.join(self.settings['input'], "blk%05d.dat" % fn)
def fetchBlock(self, extent):
'''Fetch block contents from disk given extents'''
with open(self.inFileName(extent.fn), "rb") as f:
f.seek(extent.offset)
return f.read(extent.size)
def copyOneBlock(self):
'''Find the next block to be written in the input, and copy it to the output.'''
extent = self.blockExtents.pop(self.blkCountOut)
if self.blkCountOut in self.outOfOrderData:
# If the data is cached, use it from memory and remove from the cache
rawblock = self.outOfOrderData.pop(self.blkCountOut)
self.outOfOrderSize -= len(rawblock)
else: # Otherwise look up data on disk
rawblock = self.fetchBlock(extent)
self.writeBlock(extent.inhdr, extent.blkhdr, rawblock)
def run(self):
while self.blkCountOut < len(self.blkindex):
if not self.inF:
fname = self.inFileName(self.inFn)
print("Input file " + fname)
try:
self.inF = open(fname, "rb")
except IOError:
print("Premature end of block data")
return
inhdr = self.inF.read(8)
if (not inhdr or (inhdr[0] == "\0")):
self.inF.close()
self.inF = None
self.inFn = self.inFn + 1
continue
inMagic = inhdr[:4]
if (inMagic != self.settings['netmagic']):
# Seek backwards 7 bytes (skipping the first byte in the previous search)
# and continue searching from the new position if the magic bytes are not
# found.
self.inF.seek(-7, os.SEEK_CUR)
continue
inLenLE = inhdr[4:]
su = struct.unpack("<I", inLenLE)
inLen = su[0] - 80 # length without header
blk_hdr = self.inF.read(80)
inExtent = BlockExtent(self.inFn, self.inF.tell(), inhdr, blk_hdr, inLen)
self.hash_str = calc_hash_str(blk_hdr)
if not self.hash_str in blkmap:
# Because blocks can be written to files out-of-order as of 0.10, the script
# may encounter blocks it doesn't know about. Treat as debug output.
if settings['debug_output'] == 'true':
print("Skipping unknown block " + self.hash_str)
self.inF.seek(inLen, os.SEEK_CUR)
continue
blkHeight = self.blkmap[self.hash_str]
self.blkCountIn += 1
if self.blkCountOut == blkHeight:
# If in-order block, just copy
rawblock = self.inF.read(inLen)
self.writeBlock(inhdr, blk_hdr, rawblock)
# See if we can catch up to prior out-of-order blocks
while self.blkCountOut in self.blockExtents:
self.copyOneBlock()
else: # If out-of-order, skip over block data for now
self.blockExtents[blkHeight] = inExtent
if self.outOfOrderSize < self.settings['out_of_order_cache_sz']:
# If there is space in the cache, read the data
# Reading the data in file sequence instead of seeking and fetching it later is preferred,
# but we don't want to fill up memory
self.outOfOrderData[blkHeight] = self.inF.read(inLen)
self.outOfOrderSize += inLen
else: # If no space in cache, seek forward
self.inF.seek(inLen, os.SEEK_CUR)
print("Done (%i blocks written)" % (self.blkCountOut))
if __name__ == '__main__':
if len(sys.argv) != 2:
print("Usage: linearize-data.py CONFIG-FILE")
sys.exit(1)
with open(sys.argv[1], encoding="utf8") as f:
for line in f:
# skip comment lines
m = re.search(r'^\s*#', line)
if m:
continue
# parse key=value lines
m = re.search(r'^(\w+)\s*=\s*(\S.*)$', line)
if m is None:
continue
settings[m.group(1)] = m.group(2)
# Force hash byte format setting to be lowercase to make comparisons easier.
# Also place upfront in case any settings need to know about it.
if 'rev_hash_bytes' not in settings:
settings['rev_hash_bytes'] = 'false'
settings['rev_hash_bytes'] = settings['rev_hash_bytes'].lower()
if 'netmagic' not in settings:
settings['netmagic'] = 'f9beb4d9'
if 'genesis' not in settings:
settings['genesis'] = '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
if 'input' not in settings:
settings['input'] = 'input'
if 'hashlist' not in settings:
settings['hashlist'] = 'hashlist.txt'
if 'file_timestamp' not in settings:
settings['file_timestamp'] = 0
if 'split_timestamp' not in settings:
settings['split_timestamp'] = 0
if 'max_out_sz' not in settings:
settings['max_out_sz'] = 1000 * 1000 * 1000
if 'out_of_order_cache_sz' not in settings:
settings['out_of_order_cache_sz'] = 100 * 1000 * 1000
if 'debug_output' not in settings:
settings['debug_output'] = 'false'
settings['max_out_sz'] = int(settings['max_out_sz'])
settings['split_timestamp'] = int(settings['split_timestamp'])
settings['file_timestamp'] = int(settings['file_timestamp'])
settings['netmagic'] = bytes.fromhex(settings['netmagic'])
settings['out_of_order_cache_sz'] = int(settings['out_of_order_cache_sz'])
settings['debug_output'] = settings['debug_output'].lower()
if 'output_file' not in settings and 'output' not in settings:
print("Missing output file / directory")
sys.exit(1)
blkindex = get_block_hashes(settings)
blkmap = mkblockmap(blkindex)
# Block hash map won't be byte-reversed. Neither should the genesis hash.
if not settings['genesis'] in blkmap:
print("Genesis block not found in hashlist")
else:
BlockDataCopier(settings, blkindex, blkmap).run()