Commit bcae7c9a authored by Sebastien Luttringer's avatar Sebastien Luttringer
Browse files

split tools' chroot in 3 functions 

This is done to be able to use preparation from scripts
parent d25d1032

installsystems/tools.py

+36 −12
Original line number Diff line number Diff line
@@ -333,18 +333,21 @@ def human_size(num): 
        num /= 1024.0

    return "%3.1f%s" % (num, x)



def chroot(path, shell="/bin/bash", mount=True):

def guess_distro(path):

    '''

    Chroot inside a directory and call shell

    if mount is true, mount /{proc,dev,sys} inside the chroot

    Try to detect which distro is inside a directory

    '''

    # try to guest distro

    if os.path.exists(os.path.join(path, "etc/debian_version")):

        distro="debian"

        return "debian"

    elif os.path.exists(os.path.join(path, "etc/arch-release")):

        distro="archlinux"

    else:

        distro=None

        return "archlinux"

    return None



def prepare_chroot(path, mount=True):

    '''

    Preate a chroot environment by mouting /{proc,sys,dev,dev/pts}

    and try to guess dest os to avoid daemon lauching

    '''

    # try to mount /proc /sys /dev

    if mount:

        mps = ("proc", "sys", "dev", "dev/pts")
@@ -358,6 +361,8 @@ def chroot(path, shell="/bin/bash", mount=True): 
                    check_call(["mount",  "--bind", origin, target], close_fds=True)

                except CalledProcessError as e:

                    warn("Mount failed: %s.\n" % e)

    # try to guest distro

    distro = guess_distro(path)

    # in case of debian disable policy

    if distro == "debian":

        arrow("Creating debian chroot housekeepers")
@@ -365,11 +370,16 @@ def chroot(path, shell="/bin/bash", mount=True): 
        try: open(os.path.join(path, "etc/debian_chroot"), "w").write("CHROOT")

        except: pass

        # fake policy-d

        try: open(os.path.join(path, "usr/sbin/policy-rc.d"), "w").write("#!/bin/bash\nexit 42\n")

        policy_path = os.path.join(path, "usr/sbin/policy-rc.d")

        try: open(policy_path, "w").write("#!/bin/bash\nexit 42\n")

        except: pass

    # chrooting

    arrow("Chrooting inside %s and running %s" % (path, shell))

    call(["chroot", path, shell], close_fds=True)



def unprepare_chroot(path, mount=True):

    '''

    Rollback preparation of a chroot environment inside a directory

    '''

    # try to guest distro

    distro = guess_distro(path)

    # cleaning debian stuff

    if distro == "debian":

        arrow("Removing debian chroot housekeepers")
@@ -378,9 +388,23 @@ def chroot(path, shell="/bin/bash", mount=True): 
            except: pass

    # unmounting

    if mount:

        mps = ("proc", "sys", "dev", "dev/pts")

        arrow("Unmouting filesystems")

        for mp in reversed(mps):

            target = os.path.join(path, mp)

            if os.path.ismount(target):

                arrow(target, 1)

                call(["umount", target], close_fds=True)



def chroot(path, shell="/bin/bash", mount=True):

    '''

    Chroot inside a directory and call shell

    if mount is true, mount /{proc,dev,sys} inside the chroot

    '''

    # prepare to chroot

    prepare_chroot(path, mount)

    # chrooting

    arrow("Chrooting inside %s and running %s" % (path, shell))

    call(["chroot", path, shell], close_fds=True)

    # revert preparation of chroot

    unprepare_chroot(path, mount)