Files
scylladb/scripts/create-relocatable-package.py
2018-11-28 23:56:35 +01:00

145 lines
4.7 KiB
Python
Executable File

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (C) 2018 ScyllaDB
#
#
# This file is part of Scylla.
#
# Scylla is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Scylla is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Scylla. If not, see <http://www.gnu.org/licenses/>.
#
import argparse
import io
import os
import subprocess
import tarfile
import pathlib
def ldd(executable):
'''Given an executable file, return a dictionary with the keys
containing its shared library dependencies and the values pointing
at the files they resolve to. A fake key ld.so points at the
dynamic loader.'''
libraries = {}
for ldd_line in subprocess.check_output(
['ldd', executable],
universal_newlines=True).splitlines():
elements = ldd_line.split()
if ldd_line.endswith('not found'):
raise Exception('ldd could not resolve {}'.format(elements[0]))
if elements[1] != '=>':
if elements[0].startswith('linux-vdso.so'):
# provided by kernel
continue
libraries['ld.so'] = os.path.realpath(elements[0])
else:
libraries[elements[0]] = os.path.realpath(elements[2])
return libraries
ap = argparse.ArgumentParser(description='Create a relocatable scylla package.')
ap.add_argument('dest',
help='Destination file (tar format)')
ap.add_argument('--mode', dest='mode', default='release',
help='Build mode (debug/release) to use')
args = ap.parse_args()
executables = ['build/{}/scylla'.format(args.mode),
'build/{}/iotune'.format(args.mode)]
output = args.dest
libs = {}
for exe in executables:
libs.update(ldd(exe))
ld_so = libs['ld.so']
ar = tarfile.open(output, mode='w|gz')
pathlib.Path('build/SCYLLA-RELOCATABLE-FILE').touch()
ar.add('build/SCYLLA-RELOCATABLE-FILE', arcname='SCYLLA-RELOCATABLE-FILE')
# This thunk is a shell script that arranges for the executable to be invoked,
# under the following conditions:
#
# - the same argument vector is passed to the executable, including argv[0]
# - the executable name (/proc/pid/comm, shown in top(1)) is the same
# - the dynamic linker is taken from this package rather than the executable's
# default (which is hardcoded to point to /lib64/ld-linux-x86_64.so or similar)
# - LD_LIBRARY_PATH points to the lib/ directory so shared library dependencies
# are satisified from there rather than the system default (e.g. /lib64)
# To do that, the dynamic linker is invoked using a symbolic link named after the
# executable, not its standard name. We use "bash -a" to set argv[0].
# The full tangled web looks like:
#
# foobar/bin/scylla a shell script invoking everything
# foobar/libexec/scylla.bin the real binary
# foobar/libexec/scylla a symlink to ../lib/ld.so
# foobar/lib/ld.so the dynamic linker
# foobar/lib/lib... all the other libraries
# the transformations (done by the thunk and symlinks) are:
#
# bin/scylla args -> libexec/scylla libexec/scylla.bin args -> lib/ld.so libexec/scylla.bin args
thunk = b'''\
#!/bin/bash
x="$(readlink -f "$0")"
b="$(basename "$x")"
d="$(dirname "$x")/.."
ldso="$d/libexec/$b"
realexe="$d/libexec/$b.bin"
LD_LIBRARY_PATH="$d/lib" exec -a "$0" "$ldso" "$realexe" "$@"
'''
for exe in executables:
basename = os.path.basename(exe)
ar.add(exe, arcname='libexec/' + basename + '.bin')
ti = tarfile.TarInfo(name='bin/' + basename)
ti.size = len(thunk)
ti.mode = 0o755
ti.mtime = os.stat(exe).st_mtime
ar.addfile(ti, fileobj=io.BytesIO(thunk))
ti = tarfile.TarInfo(name='libexec/' + basename)
ti.type = tarfile.SYMTYPE
ti.linkname = '../lib/ld.so'
ti.mtime = os.stat(exe).st_mtime
ar.addfile(ti)
for lib, libfile in libs.items():
ar.add(libfile, arcname='lib/' + lib)
ar.add('conf')
ar.add('dist')
ar.add('build/SCYLLA-RELEASE-FILE', arcname='SCYLLA-RELEASE-FILE')
ar.add('build/SCYLLA-VERSION-FILE', arcname='SCYLLA-VERSION-FILE')
ar.add('seastar/scripts')
ar.add('seastar/dpdk/usertools')
ar.add('install.sh')
ar.add('README.md')
ar.add('README-DPDK.md')
ar.add('NOTICE.txt')
ar.add('ORIGIN')
ar.add('licenses')
ar.add('swagger-ui')
ar.add('api')
ar.add('tools')
ar.add('scylla-housekeeping')
ar.add('scylla-gdb.py')