blob: 8da40f656ac85378c472566ca06ff019fad79a21 [file] [log] [blame]
# reproducible_build.bbclass
#
# Sets SOURCE_DATE_EPOCH in each component's build environment.
# Upstream components (generally) respect this environment variable,
# using it in place of the "current" date and time.
# See https://reproducible-builds.org/specs/source-date-epoch/
#
# After sources are unpacked but before they are patched, we set a reproducible value for SOURCE_DATE_EPOCH.
# This value should be reproducible for anyone who builds the same revision from the same sources.
#
# There are 4 ways we determine SOURCE_DATE_EPOCH:
#
# 1. Use the value from __source_date_epoch.txt file if this file exists.
# This file was most likely created in the previous build by one of the following methods 2,3,4.
# Alternatively, it can be provided by a recipe via SRC_URI.
#
# If the file does not exist:
#
# 2. If there is a git checkout, use the last git commit timestamp.
# Git does not preserve file timestamps on checkout.
#
# 3. Use the mtime of "known" files such as NEWS, CHANGLELOG, ...
# This works for well-kept repositories distributed via tarball.
#
# 4. Use the modification time of the youngest file in the source tree, if there is one.
# This will be the newest file from the distribution tarball, if any.
#
# 5. Fall back to a fixed timestamp.
#
# Once the value of SOURCE_DATE_EPOCH is determined, it is stored in the recipe's SDE_FILE.
# If none of these mechanisms are suitable, replace the do_deploy_source_date_epoch task
# with recipe-specific functionality to write the appropriate SOURCE_DATE_EPOCH into the SDE_FILE.
#
# If this file is found by other tasks, the value is exported in the SOURCE_DATE_EPOCH variable.
# SOURCE_DATE_EPOCH is set for all tasks that might use it (do_configure, do_compile, do_package, ...)
BUILD_REPRODUCIBLE_BINARIES ??= '1'
inherit ${@oe.utils.ifelse(d.getVar('BUILD_REPRODUCIBLE_BINARIES') == '1', 'reproducible_build_simple', '')}
SDE_DIR ="${WORKDIR}/source-date-epoch"
SDE_FILE = "${SDE_DIR}/__source_date_epoch.txt"
SDE_DEPLOYDIR = "${WORKDIR}/deploy-source-date-epoch"
SSTATETASKS += "do_deploy_source_date_epoch"
do_deploy_source_date_epoch () {
mkdir -p ${SDE_DEPLOYDIR}
if [ -e ${SDE_FILE} ]; then
echo "Deploying SDE from ${SDE_FILE} -> ${SDE_DEPLOYDIR}."
cp -p ${SDE_FILE} ${SDE_DEPLOYDIR}/__source_date_epoch.txt
else
echo "${SDE_FILE} not found!"
fi
}
python do_deploy_source_date_epoch_setscene () {
sstate_setscene(d)
bb.utils.mkdirhier(d.getVar('SDE_DIR'))
sde_file = os.path.join(d.getVar('SDE_DEPLOYDIR'), '__source_date_epoch.txt')
if os.path.exists(sde_file):
target = d.getVar('SDE_FILE')
bb.debug(1, "Moving setscene SDE file %s -> %s" % (sde_file, target))
os.rename(sde_file, target)
else:
bb.debug(1, "%s not found!" % sde_file)
}
do_deploy_source_date_epoch[dirs] = "${SDE_DEPLOYDIR}"
do_deploy_source_date_epoch[sstate-plaindirs] = "${SDE_DEPLOYDIR}"
addtask do_deploy_source_date_epoch_setscene
addtask do_deploy_source_date_epoch before do_configure after do_patch
def get_source_date_epoch_from_known_files(d, sourcedir):
source_date_epoch = None
newest_file = None
known_files = set(["NEWS", "ChangeLog", "Changelog", "CHANGES"])
for file in known_files:
filepath = os.path.join(sourcedir, file)
if os.path.isfile(filepath):
mtime = int(os.lstat(filepath).st_mtime)
# There may be more than one "known_file" present, if so, use the youngest one
if not source_date_epoch or mtime > source_date_epoch:
source_date_epoch = mtime
newest_file = filepath
if newest_file:
bb.debug(1, "SOURCE_DATE_EPOCH taken from: %s" % newest_file)
return source_date_epoch
def find_git_folder(d, sourcedir):
# First guess: WORKDIR/git
# This is the default git fetcher unpack path
workdir = d.getVar('WORKDIR')
gitpath = os.path.join(workdir, "git/.git")
if os.path.isdir(gitpath):
return gitpath
# Second guess: ${S}
gitpath = os.path.join(sourcedir, ".git")
if os.path.isdir(gitpath):
return gitpath
# Perhaps there was a subpath or destsuffix specified.
# Go looking in the WORKDIR
exclude = set(["build", "image", "license-destdir", "patches", "pseudo",
"recipe-sysroot", "recipe-sysroot-native", "sysroot-destdir", "temp"])
for root, dirs, files in os.walk(workdir, topdown=True):
dirs[:] = [d for d in dirs if d not in exclude]
if '.git' in dirs:
return root
bb.warn("Failed to find a git repository in WORKDIR: %s" % workdir)
return None
def get_source_date_epoch_from_git(d, sourcedir):
source_date_epoch = None
if "git://" in d.getVar('SRC_URI'):
gitpath = find_git_folder(d, sourcedir)
if gitpath:
import subprocess
source_date_epoch = int(subprocess.check_output(['git','log','-1','--pretty=%ct'], cwd=gitpath))
bb.debug(1, "git repository: %s" % gitpath)
return source_date_epoch
def get_source_date_epoch_from_youngest_file(d, sourcedir):
if sourcedir == d.getVar('WORKDIR'):
# These sources are almost certainly not from a tarball
return None
# Do it the hard way: check all files and find the youngest one...
source_date_epoch = None
newest_file = None
for root, dirs, files in os.walk(sourcedir, topdown=True):
files = [f for f in files if not f[0] == '.']
for fname in files:
filename = os.path.join(root, fname)
try:
mtime = int(os.lstat(filename).st_mtime)
except ValueError:
mtime = 0
if not source_date_epoch or mtime > source_date_epoch:
source_date_epoch = mtime
newest_file = filename
if newest_file:
bb.debug(1, "Newest file found: %s" % newest_file)
return source_date_epoch
def fixed_source_date_epoch():
bb.debug(1, "No tarball or git repo found to determine SOURCE_DATE_EPOCH")
return 0
python create_source_date_epoch_stamp() {
epochfile = d.getVar('SDE_FILE')
# If it exists we need to regenerate as the sources may have changed
if os.path.isfile(epochfile):
bb.debug(1, "Deleting existing SOURCE_DATE_EPOCH from: %s" % epochfile)
os.remove(epochfile)
sourcedir = d.getVar('S')
source_date_epoch = (
get_source_date_epoch_from_git(d, sourcedir) or
get_source_date_epoch_from_known_files(d, sourcedir) or
get_source_date_epoch_from_youngest_file(d, sourcedir) or
fixed_source_date_epoch() # Last resort
)
bb.debug(1, "SOURCE_DATE_EPOCH: %d" % source_date_epoch)
bb.utils.mkdirhier(d.getVar('SDE_DIR'))
with open(epochfile, 'w') as f:
f.write(str(source_date_epoch))
}
def get_source_date_epoch_value(d):
cached = d.getVar('__CACHED_SOURCE_DATE_EPOCH')
if cached:
return cached
epochfile = d.getVar('SDE_FILE')
source_date_epoch = 0
if os.path.isfile(epochfile):
with open(epochfile, 'r') as f:
s = f.read()
try:
source_date_epoch = int(s)
except ValueError:
bb.warn("SOURCE_DATE_EPOCH value '%s' is invalid. Reverting to 0" % s)
source_date_epoch = 0
bb.debug(1, "SOURCE_DATE_EPOCH: %d" % source_date_epoch)
else:
bb.debug(1, "Cannot find %s. SOURCE_DATE_EPOCH will default to %d" % (epochfile, source_date_epoch))
d.setVar('__CACHED_SOURCE_DATE_EPOCH', str(source_date_epoch))
return str(source_date_epoch)
export SOURCE_DATE_EPOCH ?= "${@get_source_date_epoch_value(d)}"
BB_HASHBASE_WHITELIST += "SOURCE_DATE_EPOCH"
python () {
if d.getVar('BUILD_REPRODUCIBLE_BINARIES') == '1':
d.appendVarFlag("do_unpack", "postfuncs", " create_source_date_epoch_stamp")
}