def sstate_task_postfunc(d):
    shared_state = sstate_state_fromvars(d)

    omask = os.umask(0o002)
    if omask != 0o002:
       bb.note("Using umask 0o002 (not %0o) for sstate packaging" % omask)
    sstate_package(shared_state, d)
    os.umask(omask)

    sstateinst = d.getVar("SSTATE_INSTDIR")
    d.setVar('SSTATE_FIXMEDIR', shared_state['fixmedir'])

    sstate_installpkgdir(shared_state, d)

    bb.utils.remove(d.getVar("SSTATE_BUILDDIR"), recurse=True)

sstate_task_postfunc(d)

def sstate_installpkgdir(ss, d):
    import oe.path
    import subprocess

    sstateinst = d.getVar("SSTATE_INSTDIR")
    d.setVar('SSTATE_FIXMEDIR', ss['fixmedir'])

    for f in (d.getVar('SSTATEPOSTUNPACKFUNCS') or '').split():
        # All hooks should run in the SSTATE_INSTDIR
        bb.build.exec_func(f, d, (sstateinst,))

    sstate_install(ss, d)

    return True

def sstate_state_fromvars(d, task = None):
    if task is None:
        task = d.getVar('BB_CURRENTTASK')
        if not task:
            bb.fatal("sstate code running without task context?!")
        task = task.replace("_setscene", "")

    if task.startswith("do_"):
        task = task[3:]
    inputs = (d.getVarFlag("do_" + task, 'sstate-inputdirs') or "").split()
    outputs = (d.getVarFlag("do_" + task, 'sstate-outputdirs') or "").split()
    plaindirs = (d.getVarFlag("do_" + task, 'sstate-plaindirs') or "").split()
    lockfiles = (d.getVarFlag("do_" + task, 'sstate-lockfile') or "").split()
    lockfilesshared = (d.getVarFlag("do_" + task, 'sstate-lockfile-shared') or "").split()
    fixmedir = d.getVarFlag("do_" + task, 'sstate-fixmedir') or ""
    if not task or len(inputs) != len(outputs):
        bb.fatal("sstate variables not setup correctly?!")

    if task == "populate_lic":
        d.setVar("SSTATE_PKGSPEC", "${SSTATE_SWSPEC}")
        d.setVar("SSTATE_EXTRAPATH", "")
        d.setVar('SSTATE_EXTRAPATHWILDCARD', "")

    ss = sstate_init(task, d)
    for i in range(len(inputs)):
        sstate_add(ss, inputs[i], outputs[i], d)
    ss['lockfiles'] = lockfiles
    ss['lockfiles-shared'] = lockfilesshared
    ss['plaindirs'] = plaindirs
    ss['fixmedir'] = fixmedir
    return ss

def sstate_package(ss, d):
    import oe.path
    import time

    tmpdir = d.getVar('TMPDIR')

    sstatebuild = d.expand("${WORKDIR}/sstate-build-%s/" % ss['task'])
    sde = int(d.getVar("SOURCE_DATE_EPOCH") or time.time())
    d.setVar("SSTATE_CURRTASK", ss['task'])
    bb.utils.remove(sstatebuild, recurse=True)
    bb.utils.mkdirhier(sstatebuild)
    exit = False
    for state in ss['dirs']:
        if not os.path.exists(state[1]):
            continue
        srcbase = state[0].rstrip("/").rsplit('/', 1)[0]
        # Find and error for absolute symlinks. We could attempt to relocate but its not
        # clear where the symlink is relative to in this context. We could add that markup
        # to sstate tasks but there aren't many of these so better just avoid them entirely.
        for walkroot, dirs, files in os.walk(state[1]):
            for file in files + dirs:
                srcpath = os.path.join(walkroot, file)
                if not os.path.islink(srcpath):
                    continue
                link = os.readlink(srcpath)
                if not os.path.isabs(link):
                    continue
                if not link.startswith(tmpdir):
                    continue
                bb.error("sstate found an absolute path symlink %s pointing at %s. Please replace this with a relative link." % (srcpath, link))
                exit = True
        bb.debug(2, "Preparing tree %s for packaging at %s" % (state[1], sstatebuild + state[0]))
        bb.utils.rename(state[1], sstatebuild + state[0])
    if exit:
        bb.fatal("Failing task due to absolute path symlinks")

    workdir = d.getVar('WORKDIR')
    sharedworkdir = os.path.join(d.getVar('TMPDIR'), "work-shared")
    for plain in ss['plaindirs']:
        pdir = plain.replace(workdir, sstatebuild)
        if sharedworkdir in plain:
            pdir = plain.replace(sharedworkdir, sstatebuild)
        bb.utils.mkdirhier(plain)
        bb.utils.mkdirhier(pdir)
        bb.utils.rename(plain, pdir)

    d.setVar('SSTATE_BUILDDIR', sstatebuild)
    d.setVar('SSTATE_INSTDIR', sstatebuild)

    if d.getVar('SSTATE_SKIP_CREATION') == '1':
        return

    sstate_create_package = ['sstate_report_unihash', 'sstate_create_and_sign_package']

    for f in (d.getVar('SSTATECREATEFUNCS') or '').split() + \
             sstate_create_package + \
             (d.getVar('SSTATEPOSTCREATEFUNCS') or '').split():
        # All hooks should run in SSTATE_BUILDDIR.
        bb.build.exec_func(f, d, (sstatebuild,))

    # SSTATE_PKG may have been changed by sstate_report_unihash
    siginfo = d.getVar('SSTATE_PKG') + ".siginfo"
    if not os.path.exists(siginfo):
        bb.siggen.dump_this_task(siginfo, d)
    else:
        try:
            os.utime(siginfo, None)
        except PermissionError:
            pass
        except OSError as e:
            # Handle read-only file systems gracefully
            import errno
            if e.errno != errno.EROFS:
                raise e

    return

def sstate_add(ss, source, dest, d):
    if not source.endswith("/"):
         source = source + "/"
    if not dest.endswith("/"):
         dest = dest + "/"
    source = os.path.normpath(source)
    dest = os.path.normpath(dest)
    srcbase = os.path.basename(source)
    ss['dirs'].append([srcbase, source, dest])
    return ss

def sstate_install(ss, d):
    import oe.path
    import oe.sstatesig
    import subprocess

    def prepdir(dir):
        # remove dir if it exists, ensure any parent directories do exist
        if os.path.exists(dir):
            oe.path.remove(dir)
        bb.utils.mkdirhier(dir)
        oe.path.remove(dir)

    sstateinst = d.getVar("SSTATE_INSTDIR")

    for state in ss['dirs']:
        prepdir(state[1])
        bb.utils.rename(sstateinst + state[0], state[1])

    sharedfiles = []
    shareddirs = []
    bb.utils.mkdirhier(d.expand("${SSTATE_MANIFESTS}"))

    manifest, d2 = oe.sstatesig.sstate_get_manifest_filename(ss['task'], d)

    if os.access(manifest, os.R_OK):
        bb.fatal("Package already staged (%s)?!" % manifest)

    d.setVar("SSTATE_INST_POSTRM", manifest + ".postrm")

    locks = []
    for lock in ss['lockfiles-shared']:
        locks.append(bb.utils.lockfile(lock, True))
    for lock in ss['lockfiles']:
        locks.append(bb.utils.lockfile(lock))

    for state in ss['dirs']:
        bb.debug(2, "Staging files from %s to %s" % (state[1], state[2]))
        for walkroot, dirs, files in os.walk(state[1]):
            for file in files:
                srcpath = os.path.join(walkroot, file)
                dstpath = srcpath.replace(state[1], state[2])
                #bb.debug(2, "Staging %s to %s" % (srcpath, dstpath))
                sharedfiles.append(dstpath)
            for dir in dirs:
                srcdir = os.path.join(walkroot, dir)
                dstdir = srcdir.replace(state[1], state[2])
                #bb.debug(2, "Staging %s to %s" % (srcdir, dstdir))
                if os.path.islink(srcdir):
                    sharedfiles.append(dstdir)
                    continue
                if not dstdir.endswith("/"):
                    dstdir = dstdir + "/"
                shareddirs.append(dstdir)

    # Check the file list for conflicts against files which already exist
    overlap_allowed = (d.getVar("SSTATE_ALLOW_OVERLAP_FILES") or "").split()
    match = []
    for f in sharedfiles:
        if os.path.exists(f):
            f = os.path.normpath(f)
            realmatch = True
            for w in overlap_allowed:
                w = os.path.normpath(w)
                if f.startswith(w):
                    realmatch = False
                    break
            if realmatch:
                match.append(f)
                sstate_search_cmd = "grep -rlF '%s' %s --exclude=index-* | sed -e 's:^.*/::'" % (f, d.expand("${SSTATE_MANIFESTS}"))
                search_output = subprocess.Popen(sstate_search_cmd, shell=True, stdout=subprocess.PIPE).communicate()[0]
                if search_output:
                    match.append("  (matched in %s)" % search_output.decode('utf-8').rstrip())
                else:
                    match.append("  (not matched to any task)")
    if match:
        bb.fatal("Recipe %s is trying to install files into a shared " \
          "area when those files already exist. The files and the manifests listing " \
          "them are:\n  %s\n"
          "Please adjust the recipes so only one recipe provides a given file. " % \
          (d.getVar('PN'), "\n  ".join(match)))

    if ss['fixmedir'] and os.path.exists(ss['fixmedir'] + "/fixmepath.cmd"):
        sharedfiles.append(ss['fixmedir'] + "/fixmepath.cmd")
        sharedfiles.append(ss['fixmedir'] + "/fixmepath")

    # Write out the manifest
    f = open(manifest, "w")
    for file in sharedfiles:
        f.write(file + "\n")

    # We want to ensure that directories appear at the end of the manifest
    # so that when we test to see if they should be deleted any contents
    # added by the task will have been removed first.
    dirs = sorted(shareddirs, key=len)
    # Must remove children first, which will have a longer path than the parent
    for di in reversed(dirs):
        f.write(di + "\n")
    f.close()

    # Append to the list of manifests for this PACKAGE_ARCH

    i = d2.expand("${SSTATE_MANIFESTS}/index-${SSTATE_MANMACH}")
    l = bb.utils.lockfile(i + ".lock")
    filedata = d.getVar("STAMP") + " " + d2.getVar("SSTATE_MANFILEPREFIX") + " " + d.getVar("WORKDIR") + "\n"
    manifests = []
    if os.path.exists(i):
        with open(i, "r") as f:
            manifests = f.readlines()
    # We append new entries, we don't remove older entries which may have the same
    # manifest name but different versions from stamp/workdir. See below.
    if filedata not in manifests:
        with open(i, "a+") as f:
            f.write(filedata)
    bb.utils.unlockfile(l)

    # Run the actual file install
    for state in ss['dirs']:
        if os.path.exists(state[1]):
            oe.path.copyhardlinktree(state[1], state[2])

    for plain in ss['plaindirs']:
        workdir = d.getVar('WORKDIR')
        sharedworkdir = os.path.join(d.getVar('TMPDIR'), "work-shared")
        src = sstateinst + "/" + plain.replace(workdir, '')
        if sharedworkdir in plain:
            src = sstateinst + "/" + plain.replace(sharedworkdir, '')
        dest = plain
        bb.utils.mkdirhier(src)
        prepdir(dest)
        bb.utils.rename(src, dest)

    for lock in locks:
        bb.utils.unlockfile(lock)

def sstate_init(task, d):
    ss = {}
    ss['task'] = task
    ss['dirs'] = []
    ss['plaindirs'] = []
    ss['lockfiles'] = []
    ss['lockfiles-shared'] = []
    return ss