Merge branch 'containers-minimum-101354'

Add experimental support for creating extra servers at runtime, to
be used by app containers like Flatpak or Snap. This API is still
subject to change and is not compiled in by default.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

Update NEWS

Signed-off-by: Simon McVittie <smcv@collabora.com>

system.conf: Allow creating containers on the system bus

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Allow unprivileged connections to create app-containers

This lets ordinary users create a limited number of app-containers
on the system bus.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

Revert "test/uid-permissions: Assert that AddServer is privileged"

I'm about to make that not be true.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Exercise the resource limits

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

containers: Enforce max_containers_per_user

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Enforce max_connections_per_container

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Enforce max_containers limit

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Limit the size of metadata we will store

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus: Add (unused) settings for resource limits for containers

These will be enforced in subsequent commits.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Fix whitespace]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Check that GetInstanceInfo stops working

After the container instance is removed, the method should not work.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

t/containers: Exercise trivial and non-trivial container metadata

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Add GetConnectionInstance(), GetInstanceInfo()

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/dbus-daemon: Assert absence of Containers1 credentials

These connections are not to a container server.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Add basic container info to GetConnectionCredentials()

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Containers can't use the Verbose and Stats interfaces

These are debugging interfaces, which are essentially read-only.
By default, Verbose is not available on the system bus at all and
Stats is only available to uid 0, but both are available on the
session bus, and they can be allowed for other uids by configuring
the system bus.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Add a flag for methods that can't be invoked by containers

We can relax AddServer() from PRIVILEGED to NOT_CONTAINERS when we've
put resource limits in place, although for now it must remain
PRIVILEGED because it uses up resources.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Check that connections from containers are unprivileged

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Check that containers can't make new containers

We should prevent containers from trying to put a container in our
container so we can sandbox while we sandbox. The implementation doesn't
actually have any concept of nesting or layering, so that would potentially
be privilege escalation.

At the moment, this is just prevented by METHOD_FLAG_PRIVILEGED. When we
remove that flag (after we've introduced better resource limits), we can
specifically restrict this method to not be called by containers
instead. This test will make sure we do.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/driver: Treat connections from inside containers as unprivileged

Even if the uid matches, a contained app shouldn't count as the owner
of the bus.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Indicate in loginfo whether connection is contained

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Assert that InstanceRemoved is emitted

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Emit InstanceRemoved signal

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Exercise the various ways to stop a container

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Don't allow stopping other users' containers

On the system bus, that would be a denial of service, assuming we
relax the access-control from METHOD_FLAG_PRIVILEGED to a new
METHOD_FLAG_NOT_CONTAINERS later.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Implement methods to stop containers explicitly

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Give each instance a list of all its connections

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Fix minor conflict]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Shut down container servers when initiator goes away

We will eventually want to have other ways to signal that a
container server should stop listening, so that the container manager
doesn't have to stay on D-Bus (fd-passing the read end of a pipe
whose write end will be closed by the container manager has been
suggested as easier to deal with for Flatpak/Bubblewrap), but for
now we're doing the simplest possible thing.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Link each container to its initiating connection

We will need this to be able to shut down the container when its
creator vanishes.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Fix minor conflict]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Each connection to a container holds a reference

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Fix minor conflicts]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Exercise connecting to the new socket as the wrong uid

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Require connecting uid to match caller of AddServer

If we're strict now, we can relax this later (either with a named
parameter or always); but if we're lenient now, we'll be stuck with it
forever, so be strict.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Exercise a successful call to AddServer

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Set up new connections to join the bus

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus_context_add_incoming_connection: factor out

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Fix minor conflict]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Create a DBusServer and add it to the main loop

This means we can accept connections on the new socket. For now, we
don't process them and they get closed.

For the system bus (or root's session bus, where the difference is
harmless but makes automated testing easier), rely on system-wide
infrastructure to create /run/dbus/containers. The upstream dbus
distribution no longer contains integration glue for non-systemd boot
systems, but downstreams that maintain a non-systemd boot system and are
interested in the Containers interface should create /run/dbus/containers
during boot.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Build a global data structure for container instances

We still don't actually create a DBusServer for incoming connections
at this point, much less accept incoming connections.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: Exercise the new parameter checking

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

bus/containers: Do some basic checking on the parameters

In particular, we now fail early if we can't extract the file
descriptor, or if there are named parameters (none are supported yet).

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/containers: New test

So far it only exercises SupportedArguments.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

test/uid-permissions: Assert that AddServer is privileged

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

travis-ci: Do at least one build with and one without containers

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

driver: Add a stub implementation of the Containers1 interface

For now, this is considered to be a privileged operation, because the
resource-limiting isn't wired up yet. It only contains the bare minimum
of API.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

spec: Document the initial Containers1 interface

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=101354

_dbus_test_oom_handling: print TAP diagnostics

These aren't *that* verbose, so it seems OK to print them all the time,
not just in the needlessly spammy verbose mode.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

tests: Add the ability to multiply up test timeouts

Tests that brute-force OOM code paths can be rather slow.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

test-utils: Separate failable and non-failable functions

test_object_try_whatever() now has libdbus-like OOM handling,
while test_object_whatever() has GLib-like OOM handling. This is
because an overwhelming majority of the callers of these functions
either didn't check for OOM anyway, or checked for it but then
aborted. In the uncommon case where we do care, we can use the _try_
version.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

test_connection_setup: Don't crash on unlikely OOM

If _dbus_loop_queue_dispatch fails with OOM, we'd try to free cd,
while cd is already owned by the connection's timeout functions.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

test_try_connect_to_bus: Cope with OOM while setting up connection

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

test_try_connect_to_bus: Don't leak the connection on OOM

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

dbus_message_demarshal: Set error if we can't allocate the loader

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

DBusHeader: Add a diagram of the header

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

_dbus_header_load: Operate on the entire string, not a substring

This function worked with a (string,position,length) triple, but it
turns out to only have one caller, which tells it to look at the
entire string anyway. It'll be easier to document if all the offsets
start from 0.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=100317
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>

_dbus_server_new_for_socket: Iterate over arrays as intended

Commit 0c03b505 was meant to clear all the fds indexed by j in
[0, n_fds), which socket_disconnect() can't be allowed to close
(because on failure the caller remains responsible for closing them);
but instead it closed the one we failed to add to the main loop
(fd i), repeatedly.

Similarly, it was meant to invalidate all the watches indexed by j
in [i, n_fds) (the one we failed to add to the main loop and the ones
we didn't try to add to the main loop yet), which socket_disconnect()
can't be allowed to see (because it would fail to remove them from
the main loop and hit an assertion failure); but instead it invalidated
fd i, repeatedly.

These happen to be the same thing if you only have one fd, resulting
in the test-case passing on an IPv4-only system, but failing on a
system with both IPv4 and IPv6.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104
Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>

NEWS for 1.13.x

Signed-off-by: Simon McVittie <smcv@collabora.com>

tests: Use test_main_context_call_and_wait

Also use test_oom() where the relevant lines are changing anyway.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

test_main_context_call_and_wait: Add

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

test-utils: Use TAP syntax to die with a fatal error

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

tests: Don't use the same variable for call and reply

It seemed like a nice idea at the time, but I now think it's more
confusing than it's worth.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

test/sd-activation: Make more use of dbus_clear_message()

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

tests: Don't leak pending calls

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

test/dbus-daemon: Don't leak method call messages if we skip tests

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

test_peer_ping: Don't leak one method call per invocation

Previously, we allocated m both during initialization, and after
deciding not to skip this test.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103600

_dbus_server_new_for_tcp_socket: Simplify error unwinding

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_server_new_for_socket: Simplify error unwinding

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

Add a targeted test for OOM during _dbus_server_new_for_tcp_socket()

This also covers _dbus_server_new_for_socket(), which is one of the
worse places in terms of complexity of the error-unwinding path
(3 labels).

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

dbus-nonce: Don't crash on encountering OOM

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_listen_tcp_socket: Don't rely on dbus_realloc setting errno

dbus_realloc() doesn't guarantee to set errno (if it did, the
only reasonable thing it could set it to would be ENOMEM). In
particular, faking OOM conditions doesn't set it. This can cause an
assertion failure when OOM tests assert that the only error that can
validly occur is DBUS_ERROR_NO_MEMORY.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_server_new_for_tcp_socket: Don't pile up errors on OOM

If _dbus_noncefile_create() has failed and set error, it is incorrect
for us to set it again.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_server_new_for_launchd: Don't leak fd on failure

If _dbus_server_new_for_socket() fails, it is the caller's
responsibility to close the fds. All other callers did this.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_server_new_for_socket: Properly disconnect during error unwinding

_dbus_server_finalize_base() asserts that the socket has been
disconnected, but in some OOM code paths we would call it without
officially disconnecting. Do so.

This means we need to be a bit more careful about what is
socket_disconnect()'s responsibility to clean up, what is
_dbus_server_new_for_socket()'s responsibility, and what is the caller's
responsibility.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_server_new_for_socket: Invalidate watches during error unwinding

We assert that every watch is invalidated before it is freed, but
in some OOM code paths this didn't happen.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

_dbus_transport_new_for_socket: Simplify with _DBUS_STRING_INIT_INVALID

This is one of the few places that has test coverage for all the OOM
code paths. It was also one of the worst (most complicated)
error-unwinding locations, with labels failed_0 up to failed_4.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

DBusString: Add _DBUS_STRING_INIT_INVALID and allow "freeing" it

This means we can finally use patterns like this:

      DBusString buffer = _DBUS_STRING_INIT_INVALID;
      dbus_bool_t ret = FALSE;

      ... some long setup ...

      if (!_dbus_string_init (&buffer))
        goto out;

      ... some long operation ...

      ret = TRUE;

    out:
      ... free things ...
      _dbus_string_free (&buffer);
      ... free more things ...
      return ret;

without having to have a separate boolean to track whether buffer has
been initialized.

One observable difference is that if s is a "const" (borrowed pointer)
string, _dbus_string_free (&s) now sets it to be invalid. Previously,
it would have kept its (borrowed pointer) contents, which seems like
a violation of least-astonishment.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

DBusString: Reverse the sense of ->invalid

It's easier to implement a stack-allocated string that is valid to
free (but for no other purpose) if we consider all-bits-zero to be
invalid.

Signed-off-by: Simon McVittie <smcv@collabora.com>
Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=89104

Remove references to test/data/incomplete-messages too

Signed-off-by: Simon McVittie <smcv@collabora.com>

tests: Remove leftover references to valid-messages directory

Now that the directory doesn't exist in git, the embedded tests fail
in a clean git checkout.

Signed-off-by: Simon McVittie <smcv@collabora.com>

Update NEWS for 1.13.x test changes

Signed-off-by: Simon McVittie <smcv@collabora.com>

Remove test data in the "message builder" domain-specific language

These tests were disabled by commit 9c3d566, which rewrote the D-Bus
type system to be fully recursive, back in 2005. The message builder
was subsequently removed by commit 9d21554, also in early 2005.

It will probably take significant work to turn these files into
test-cases that use the current D-Bus type system and so can be run
this decade. Until that work is done, let's not ship them: we can
always fetch them from git history if we want them.

The single .message-raw file can still be read and has been retained,
although it hasn't actually tested the intended failure mode since
2005 due to changes to the D-Bus specification (it is a wire-protocol
version 0 message, and the recursive type system introduced in commit
9c3d566 changed the wire-protocol version to 1).

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103758

_dbus_test_diag: Flush stdout after each diagnostic

If we crash, we'll want to know what the most recent diagnostic was.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

dispatch test: Output finer-grained TAP

This lets us see which bits are painfully slow. (Spoilers:
check_existent_service_no_auto_start.)

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

test-bus*: Output TAP directly

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

test-dbus: Produce machine-readable TAP output

See http://testanything.org/ for more information on TAP.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

bus: Silence the output of the test services when doing OOM testing

The echo service frequently fails to connect to the bus when we are
testing OOM code paths, again causing a lot of noise in the log.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

bus: Silence most log messages when testing OOM handling

In parts of the OOM testing, our logging produces multiple megabytes
of output. Let's not do that.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Unix: Flush stdout and stderr streams before forking

stdout and stderr are close-on-exec and buffered, so we can't rely on
their buffers being empty. If we continue to execute application code
after forking (as opposed to immediately exec()ing), then the child
process might later flush the libc stdio buffers, resulting in
output that is printed by the parent also being printed by the child.

In particular, test-bus.log sometimes grows extremely large for
this reason, because this test repeatedly attempts to carry out
legacy activation.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Prefer to use _dbus_test_fatal() for assertion failures in tests

This is a little more self-documenting - it justifies why it's
acceptable to fail hard on out-of-memory conditions. _dbus_test_fatal()
isn't compiled unless we are compiling embedded tests, so compiling
with embedded tests disabled provides reasonable confidence that we
aren't using _dbus_test_fatal() inappropriately.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Use _dbus_test_fatal to include more detail in test failure diagnostics

Unlike _dbus_assert_not_reached(), this new function takes a printf-style
format string, so we don't need to use a _dbus_warn() to explain why
the failure occurred (unless the failure message is multi-line).

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Embedded tests: Emit TAP diagnostics instead of printf

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Add utility functions to emit TAP diagnostics and fatal errors

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Add an explanatory comment as suggested]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Do not export dbus_internal_do_not_use_run_tests if unused

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Windows autolaunch: Turn stdout spam into stderr spam

This is still not how warnings and diagnostics should be done
(the advice should probably be included in the DBusError) but at least
this way it won't interfere with machine-readable output on stdout.
See also https://bugs.freedesktop.org/show_bug.cgi?id=103756

Reviewed-by: Philip Withnall <withnall@endlessm.com>
[smcv: Added a reference to #103756]
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Remove commented-out printf debugging

Printing to stdout would interfere with generating TAP syntax.

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Signed-off-by: Simon McVittie <smcv@collabora.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103601

Update NEWS for 1.13.x

Signed-off-by: Simon McVittie <smcv@collabora.com>

Add a missing space in logging output

Reviewed-by: Philip Withnall <withnall@endlessm.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=103729

Merge branch 'dbus-1.12'

Start 1.12.4

Signed-off-by: Simon McVittie <smcv@collabora.com>

1.12.2

Signed-off-by: Simon McVittie <smcv@collabora.com>

Update NEWS for 1.12.x

Signed-off-by: Simon McVittie <smcv@collabora.com>