Re: [Libguestfs] [libnbd PATCH] nbdsh: Add -b option to simplify h.block_status

We decided to not request the "base:allocation" context by default (if a client wants to use block_status on a different context, then they'd have to get any default request out of the way); however, block status is useless without at least one meta context. This adds a convenience knob for requesting that, and has the nice benefit of working with the --connect command line option (previously, if you wanted to use block_status, you could not use --connect, because requesting the meta context must happen before the connection).

sh/nbdsh.pod | 9 +++++++ python/nbdsh.py | 4 +++ sh/Makefile.am | 4 ++- sh/test-context.sh | 62 ++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 78 insertions(+), 1 deletion(-) create mode 100755 sh/test-context.sh diff --git a/sh/nbdsh.pod b/sh/nbdsh.pod index d7fc315..6c540c7 100644 --- a/sh/nbdsh.pod +++ b/sh/nbdsh.pod @@ -56,6 +56,15 @@ __EXAMPLES_HEXDUMP__ Display brief command line help and exit. +=item B<-b> + +=item B<--base-allocation> + +Request the use of the "base:allocation" meta context, which is the +most common context used with L<nbd_block_status(3)>. This is +equivalent to calling S<C<h.set_meta_context +(nbd.CONTEXT_BASE_ALLOCATION)>> in the shell prior to connecting. + =item B<-c> 'COMMAND ...' =item B<--command> 'COMMAND ...' diff --git a/python/nbdsh.py b/python/nbdsh.py index 319b0f0..00bc6bc 100644 --- a/python/nbdsh.py +++ b/python/nbdsh.py @@ -27,6 +27,8 @@ def shell(): epilog = '''Please read the nbdsh(1) manual page for full usage.''' parser = argparse.ArgumentParser (prog='nbdsh', description=description, epilog=epilog) + parser.add_argument ('-b', '--base-allocation', action='store_true', + help='request the "base:allocation" meta context') parser.add_argument ('--connect', metavar='URI', help="connect to NBD URI") parser.add_argument ('-c', '--command', action='append', @@ -52,6 +54,8 @@ exit() or Ctrl-D # Quit the shell help (nbd) # Display documentation ''' + if args.base_allocation: + h.add_meta_context (nbd.CONTEXT_BASE_ALLOCATION) if args.connect is not None: h.connect_uri (args.connect) # If there are no -c or --command parameters, go interactive, diff --git a/sh/Makefile.am b/sh/Makefile.am index 8f70e69..415e241 100644 --- a/sh/Makefile.am +++ b/sh/Makefile.am @@ -21,6 +21,7 @@ EXTRA_DIST = \ nbdsh.pod \ examples/LICENSE-FOR-EXAMPLES \ examples/hexdump.sh \ + test-context.sh \ test-help.sh \ test-pattern.sh \ test-version.sh \ @@ -43,7 +44,7 @@ nbdsh.1: nbdsh.pod $(top_builddir)/podwrapper.pl endif HAVE_POD -TESTS_ENVIRONMENT = LIBNBD_DEBUG=1 EXP_VERSION=$(VERSION) +TESTS_ENVIRONMENT = LIBNBD_DEBUG=1 NBDKIT_DEBUG=1 EXP_VERSION=$(VERSION) LOG_COMPILER = $(top_builddir)/run TESTS = \ test-help.sh \ @@ -53,6 +54,7 @@ TESTS = \ if HAVE_NBDKIT TESTS += \ + test-context.sh \ test-pattern.sh \ $(NULL) diff --git a/sh/test-context.sh b/sh/test-context.sh new file mode 100755 index 0000000..55f9b53 --- /dev/null +++ b/sh/test-context.sh @@ -0,0 +1,62 @@ +#!/usr/bin/env bash +# nbd client library in userspace +# Copyright (C) 2019 Red Hat Inc. +# +# This library is free software; you can redistribute it and/or +# modify it under the terms of the GNU Lesser General Public +# License as published by the Free Software Foundation; either +# version 2 of the License, or (at your option) any later version. +# +# This library is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +# Lesser General Public License for more details. +# +# You should have received a copy of the GNU Lesser General Public +# License along with this library; if not, write to the Free Software +# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + +# Test effects of nbdsh -b +fail=0 + +# Without -b, no meta context is requested +output=$(nbdkit -U - null --run 'nbdsh \ + --connect "nbd+unix://?socket=$unixsocket" \ + -c "print (h.can_meta_context (nbd.CONTEXT_BASE_ALLOCATION))" </dev/null') +if test "x$output" != xFalse; then + echo "$0: unexpected output: $output" + fail=1 +fi + +# With -b (and a server that supports it), meta context works. +output=$(nbdkit -U - null --run 'nbdsh \ + -b --connect "nbd+unix://?socket=$unixsocket" \ + -c "print (h.can_meta_context (nbd.CONTEXT_BASE_ALLOCATION))" </dev/null') +if test "x$output" != xTrue; then + echo "$0: unexpected output: $output" + fail=1 +fi + +# Again, but with -b after --connect +output=$(nbdkit -U - null --run 'nbdsh \ + --connect "nbd+unix://?socket=$unixsocket" --base-allocation \ + -c "print (h.can_meta_context (nbd.CONTEXT_BASE_ALLOCATION))" </dev/null') +if test "x$output" != xTrue; then + echo "$0: unexpected output: $output" + fail=1 +fi + +if [[ $(nbdkit --help) =~ --no-sr ]]; then + # meta context depends on server cooperation + output=$(nbdkit -U - --no-sr null --run 'nbdsh \ + --connect "nbd+unix://?socket=$unixsocket" --base-allocation \ + -c "print (h.can_meta_context (nbd.CONTEXT_BASE_ALLOCATION))" </dev/null') + if test "x$output" != xFalse; then + echo "$0: unexpected output: $output" + fail=1 + fi +else + echo "$0: nbdkit lacks --no-sr" +fi + +exit $fail -- 2.21.0 _______________________________________________ Libguestfs mailing list Libguestfs(a)redhat.com https://www.redhat.com/mailman/listinfo/libguestfs