def _make_create_ops_subvolume(subvols: TempSubvolumes, path: bytes) -> Subvol:
'Exercise all the send-stream ops that can occur on a new subvolume.'
subvol = subvols.create(path)
run = subvol.run_as_root
# `cwd` is intentionally prohibited with `run_as_root`
def p(sv_path):
return subvol.path(sv_path).decode()
# Due to an odd `btrfs send` implementation detail, creating a file or
# directory emits a rename from a temporary name to the final one.
run(['mkdir', p('hello')]) # mkdir,rename
run(['mkdir', p('dir_to_remove')])
run(['touch', p('hello/world')]) # mkfile,utimes,chmod,chown
run([ # set_xattr
'setfattr',
'-n',
'user.test_attr',
'-v',
'chickens',
p('hello/'),
])
run(['mknod', p('buffered'), 'b', '1337', '31415']) # mknod
run(['chmod', 'og-r', p('buffered')]) # chmod a device
run(['mknod', p('unbuffered'), 'c', '1337', '31415'])
run(['mkfifo', p('fifo')]) # mkfifo
run([
'python3',
'-c',
(
'import os, sys, socket as s\n'
'dir, base = os.path.split(sys.argv[1])\n'
# Otherwise, we can easily get "AF_UNIX path too long"
'os.chdir(os.path.join(".", dir))\n'
'with s.socket(s.AF_UNIX, s.SOCK_STREAM) as sock:\n'
' sock.bind(base)\n' # mksock
),
p('unix_sock')
])
run(['ln', p('hello/world'), p('goodbye')]) # link
run(['ln', '-s', 'hello/world', p('bye_symlink')]) # symlink
run([ # update_extent
# 56KB was chosen so that `btrfs send` emits more than 1 write,
# specifically 48KB + 8KB.
'dd',
'if=/dev/zero',
'of=' + p('56KB_nuls'),
'bs=1024',
'count=56',
])
run([ # clone
'cp',
'--reflink=always',
p('56KB_nuls'),
p('56KB_nuls_clone'),
])
# Make a file with a 16KB hole in the middle.
run([
'dd',
'if=/dev/zero',
'of=' + p('zeros_hole_zeros'),
'bs=1024',
'count=16',
])
run(['truncate', '-s', str(32 * 1024), p('zeros_hole_zeros')])
run([
'dd',
'if=/dev/zero',
'of=' + p('zeros_hole_zeros'),
'oflag=append',
'conv=notrunc',
'bs=1024',
'count=16',
])
# A trailing hole exercises the `truncate` sendstream command.
run(['bash', '-c', 'echo hello > ' + shlex.quote(p('hello_big_hole'))])
run(['truncate', '-s', '1G', p('hello_big_hole')])
# This just serves to show that `btrfs send` ignores nested subvolumes.
# There is no mention of `nested_subvol` in the send-stream.
nested_subvol = subvols.create(p('nested_subvol'))
nested_subvol.run_as_root(['touch', nested_subvol.path('borf')])
nested_subvol.run_as_root(['mkdir', nested_subvol.path('beep')])
return subvol
def _make_create_ops_subvolume(subvols: TempSubvolumes, path: bytes) -> Subvol:
'Exercise all the send-stream ops that can occur on a new subvolume.'
subvol = subvols.create(path)
run = partial(subvol.run_as_root, cwd=subvol.path())
# Due to an odd `btrfs send` implementation detail, creating a file or
# directory emits a rename from a temporary name to the final one.
run(['mkdir', 'hello']) # mkdir,rename
run(['mkdir', 'dir_to_remove'])
run(['touch', 'hello/world']) # mkfile,utimes,chmod,chown
run([ # set_xattr
'setfattr',
'-n',
'user.test_attr',
'-v',
'chickens',
'hello/',
])
run(['mknod', 'buffered', 'b', '1337', '31415']) # mknod
run(['chmod', 'og-r', 'buffered']) # chmod a device
run(['mknod', 'unbuffered', 'c', '1337', '31415'])
run(['mkfifo', 'fifo']) # mkfifo
run([
'python3',
'-c',
(
'import socket as s\n'
'with s.socket(s.AF_UNIX, s.SOCK_STREAM) as sock:\n'
' sock.bind("unix_sock")\n' # mksock
)
])
run(['ln', 'hello/world', 'goodbye']) # link
run(['ln', '-s', 'hello/world', 'bye_symlink']) # symlink
run([ # update_extent
# 56KB was chosen so that `btrfs send` emits more than 1 write,
# specifically 48KB + 8KB.
'dd',
'if=/dev/zero',
'of=56KB_nuls',
'bs=1024',
'count=56',
])
run([ # clone
'cp',
'--reflink=always',
'56KB_nuls',
'56KB_nuls_clone',
])
# Make a file with a 16KB hole in the middle.
run(['dd', 'if=/dev/zero', 'of=zeros_hole_zeros', 'bs=1024', 'count=16'])
run(['truncate', '-s', str(32 * 1024), 'zeros_hole_zeros'])
run([
'dd',
'if=/dev/zero',
'of=zeros_hole_zeros',
'oflag=append',
'conv=notrunc',
'bs=1024',
'count=16',
])
# This just serves to show that `btrfs send` ignores nested subvolumes.
# There is no mention of `nested_subvol` in the send-stream.
nested_subvol = subvols.create(subvol.path(b'nested_subvol'))
run2 = partial(nested_subvol.run_as_root, cwd=nested_subvol.path())
run2(['touch', 'borf'])
run2(['mkdir', 'beep'])
return subvol