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Diffstat (limited to 'meta/classes/reproducible_build.bbclass')
| -rw-r--r-- | meta/classes/reproducible_build.bbclass | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/meta/classes/reproducible_build.bbclass b/meta/classes/reproducible_build.bbclass new file mode 100644 index 0000000000..39b6e40cac --- /dev/null +++ b/meta/classes/reproducible_build.bbclass @@ -0,0 +1,179 @@ +# 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 () { + echo "Deploying SDE to ${SDE_DIR}." + mkdir -p ${SDE_DEPLOYDIR} + if [ -e ${SDE_FILE} ]; then + cp -p ${SDE_FILE} ${SDE_DEPLOYDIR}/__source_date_epoch.txt + fi +} + +python do_deploy_source_date_epoch_setscene () { + sstate_setscene(d) + bb.utils.mkdirhier(d.getVar('SDE_DIR')) + sde_file = os.path.join(d.getVar('SDE_DEPLOYDIR'), '__source_date_epoch.txt') + if os.path.exists(sde_file): + os.rename(sde_file, d.getVar('SDE_FILE')) +} + +do_deploy_source_date_epoch[dirs] = "${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 do_create_source_date_epoch_stamp() { + epochfile = d.getVar('SDE_FILE') + if os.path.isfile(epochfile): + bb.debug(1, "Reusing SOURCE_DATE_EPOCH from: %s" % epochfile) + return + + 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)) +} + +BB_HASHBASE_WHITELIST += "SOURCE_DATE_EPOCH" + +python () { + if d.getVar('BUILD_REPRODUCIBLE_BINARIES') == '1': + d.appendVarFlag("do_unpack", "postfuncs", " do_create_source_date_epoch_stamp") + epochfile = d.getVar('SDE_FILE') + source_date_epoch = "0" + if os.path.isfile(epochfile): + with open(epochfile, 'r') as f: + source_date_epoch = f.read() + bb.debug(1, "SOURCE_DATE_EPOCH: %s" % source_date_epoch) + d.setVar('SOURCE_DATE_EPOCH', source_date_epoch) +} |