Merge tag 'pull-request-2024-05-29' of https://gitlab.com/thuth/qemu into staging

* Fix and improve PER emulation on s390x
* Fix problems of the build-oss-fuzz CI job
* Fix broken update-linux-heade

Merge tag 'pull-request-2024-05-29' of https://gitlab.com/thuth/qemu into staging

* Fix and improve PER emulation on s390x
* Fix problems of the build-oss-fuzz CI job
* Fix broken update-linux-headers.sh script
* Fixes for compiling with -fsanitize=undefined on latest Clang versions

# -----BEGIN PGP SIGNATURE-----
#
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# 51UdsNvZV9WoacVk+L3c2MgIDAXsDOhTSpGKxgWZKgvxhczhr/iOEmWI+oyag7oD
# JZfHzwgdwFywumgMrLUrvf6274cyoDNIjpSFnfw0h2Ynp3qkpyigVw5gtP5sfQgD
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# PmBaVoBttylOtr/S/I8KgJSmaQG0V/Sui7/5iyouZ26VFqakPnNzbxSDlJOEZ7k7
# GigybdjLSy6OWg0IfTOpuxsB3Cw/P2VZrNoO9xUmrjXpdBA/8BCkhmTNYu3QRvS1
# Mwgdyxqdy8I=
# =2/Y3
# -----END PGP SIGNATURE-----
# gpg: Signature made Wed 29 May 2024 03:52:05 AM PDT
# gpg: using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg: issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg: aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg: aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# gpg: aka "Thomas Huth <huth@tuxfamily.org>" [full]

* tag 'pull-request-2024-05-29' of https://gitlab.com/thuth/qemu: (22 commits)
qapi: Do not cast function pointers
lockable: Do not cast function pointers
qemu-keymap: Make references to allocations static
scripts/update-linux-headers.sh: Fix the path of setup_data.h
scripts/update-linux-headers.sh: Remove temporary directory inbetween
hw/s390x: Remove unused macro VMSTATE_ADAPTER_ROUTES
fuzz: disable leak-detection for oss-fuzz builds
fuzz: specify audiodev for usb-audio
tests/tcg/s390x: Add per.S
target/s390x: Adjust check of noreturn in translate_one
target/s390x: Simplify per_ifetch, per_check_exception
target/s390x: Fix helper_per_ifetch flags
target/s390x: Raise exception from per_store_real
target/s390x: Raise exception from helper_per_branch
target/s390x: Split per_breaking_event from per_branch_*
target/s390x: Simplify help_branch
target/s390x: Introduce help_goto_indirect
target/s390x: Disable conditional branch-to-next for PER
target/s390x: Record separate PER bits in TB flags
target/s390x: Update CR9 bits
...

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

show more ...

qapi: Do not cast function pointers

Using -fsanitize=undefined with Clang v18 causes an error if function
pointers are casted:

qapi/qapi-clone-visitor.c:188:5: runtime error: call to function visi

qapi: Do not cast function pointers

Using -fsanitize=undefined with Clang v18 causes an error if function
pointers are casted:

qapi/qapi-clone-visitor.c:188:5: runtime error: call to function visit_type_SocketAddress through pointer to incorrect function type 'bool (*)(struct Visitor *, const char *, void **, struct Error **)'
/tmp/qemu-ubsan/qapi/qapi-visit-sockets.c:487: note: visit_type_SocketAddress defined here
#0 0x5642aa2f7f3b in qapi_clone qapi/qapi-clone-visitor.c:188:5
#1 0x5642aa2c8ce5 in qio_channel_socket_listen_async io/channel-socket.c:285:18
#2 0x5642aa2b8903 in test_io_channel_setup_async tests/unit/test-io-channel-socket.c:116:5
#3 0x5642aa2b8204 in test_io_channel tests/unit/test-io-channel-socket.c:179:9
#4 0x5642aa2b8129 in test_io_channel_ipv4 tests/unit/test-io-channel-socket.c:323:5
...

It also prevents enabling the strict mode of CFI which is currently
disabled with -fsanitize-cfi-icall-generalize-pointers.

The problematic casts are necessary to pass visit_type_T() and
visit_type_T_members() as callbacks to qapi_clone() and qapi_clone_members(),
respectively. Open-code these two functions to avoid the callbacks, and
thus the type casts.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2346
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240524-xkb-v4-3-2de564e5c859@daynix.com>
[thuth: Improve commit message according to Markus' suggestions]
Signed-off-by: Thomas Huth <thuth@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2020-07-07-v2' into staging

Error reporting patches patches for 2020-07-07

# gpg: Signature made Fri 10 Jul 2020 14:24:42 BST
# gpg:

Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2020-07-07-v2' into staging

Error reporting patches patches for 2020-07-07

# gpg: Signature made Fri 10 Jul 2020 14:24:42 BST
# gpg: using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg: issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-error-2020-07-07-v2: (53 commits)
xen: Use ERRP_GUARD()
nbd: Use ERRP_GUARD()
virtio-9p: Use ERRP_GUARD()
fw_cfg: Use ERRP_GUARD()
pflash: Use ERRP_GUARD()
sd: Use ERRP_GUARD()
scripts: Coccinelle script to use ERRP_GUARD()
error: New macro ERRP_GUARD()
hmp: Ignore Error objects where the return value suffices
qdev: Ignore Error objects where the return value suffices
qemu-img: Ignore Error objects where the return value suffices
error: Avoid error_propagate() after migrate_add_blocker()
qapi: Purge error_propagate() from QAPI core
qapi: Smooth visitor error checking in generated code
qapi: Smooth another visitor error checking pattern
block/parallels: Simplify parallels_open() after previous commit
error: Reduce unnecessary error propagation
error: Eliminate error_propagate() manually
error: Eliminate error_propagate() with Coccinelle, part 2
error: Eliminate error_propagate() with Coccinelle, part 1
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

qapi: Make visitor functions taking Error ** return bool, not void

See recent commit "error: Document Error API usage rules" for
rationale.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Revi

qapi: Make visitor functions taking Error ** return bool, not void

See recent commit "error: Document Error API usage rules" for
rationale.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-18-armbru@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches for 2.11.0-rc2

# gpg: Signature made Fri 17 Nov 2017 17:58:36 GMT
# gpg: using RSA key

Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches for 2.11.0-rc2

# gpg: Signature made Fri 17 Nov 2017 17:58:36 GMT
# gpg: using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (25 commits)
iotests: Make 087 pass without AIO enabled
block: Make bdrv_next() keep strong references
qcow2: Fix overly broad madvise()
qcow2: Refuse to get unaligned offsets from cache
qcow2: Add bounds check to get_refblock_offset()
block: Guard against NULL bs->drv
qcow2: Unaligned zero cluster in handle_alloc()
qcow2: check_errors are fatal
qcow2: reject unaligned offsets in write compressed
iotests: Add test for failing qemu-img commit
tests: Add check-qobject for equality tests
iotests: Add test for non-string option reopening
block: qobject_is_equal() in bdrv_reopen_prepare()
qapi: Add qobject_is_equal()
qapi/qlist: Add qlist_append_null() macro
qapi/qnull: Add own header
qcow2: fix image corruption on commit with persistent bitmap
iotests: test clearing unknown autoclear_features by qcow2
block: Fix permissions in image activation
qcow2: fix image corruption after committing qcow2 image into base
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

Merge remote-tracking branch 'mreitz/tags/pull-block-2017-11-17' into queue-block

Block patches for 2.11.0-rc2

# gpg: Signature made Fri Nov 17 18:22:07 2017 CET
# gpg: using RSA key

Merge remote-tracking branch 'mreitz/tags/pull-block-2017-11-17' into queue-block

Block patches for 2.11.0-rc2

# gpg: Signature made Fri Nov 17 18:22:07 2017 CET
# gpg: using RSA key F407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1 1829 F407 DB00 61D5 CF40

* mreitz/tags/pull-block-2017-11-17:
iotests: Make 087 pass without AIO enabled
block: Make bdrv_next() keep strong references
qcow2: Fix overly broad madvise()
qcow2: Refuse to get unaligned offsets from cache
qcow2: Add bounds check to get_refblock_offset()
block: Guard against NULL bs->drv
qcow2: Unaligned zero cluster in handle_alloc()
qcow2: check_errors are fatal
qcow2: reject unaligned offsets in write compressed
iotests: Add test for failing qemu-img commit
tests: Add check-qobject for equality tests
iotests: Add test for non-string option reopening
block: qobject_is_equal() in bdrv_reopen_prepare()
qapi: Add qobject_is_equal()
qapi/qlist: Add qlist_append_null() macro
qapi/qnull: Add own header

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

qapi/qnull: Add own header

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <arm

qapi/qnull: Add own header

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20171114180128.17076-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-07-18-v2' into staging

QAPI patches for 2017-07-18

# gpg: Signature made Mon 24 Jul 2017 12:40:56 BST
# gpg: using RS

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-07-18-v2' into staging

QAPI patches for 2017-07-18

# gpg: Signature made Mon 24 Jul 2017 12:40:56 BST
# gpg: using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2017-07-18-v2:
migration: Use JSON null instead of "" to reset parameter to default
migration: Unshare MigrationParameters struct for now
migration: Add TODO comments on duplication of QAPI_CLONE()
migration: Clean up around tls_creds, tls_hostname
hmp: Clean up and simplify hmp_migrate_set_parameter()
block: Use JSON null instead of "" to disable backing file
tests/test-qobject-input-visitor: Drop redundant test
qapi: Introduce a first class 'null' type
qapi: Use QNull for a more regular visit_type_null()
qapi: Separate type QNull from QObject

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

qapi: Use QNull for a more regular visit_type_null()

Make visit_type_null() take an @obj argument like its buddies. This
helps keep the next commit simple.

Signed-off-by: Markus Armbruster <armbru

qapi: Use QNull for a more regular visit_type_null()

Make visit_type_null() take an @obj argument like its buddies. This
helps keep the next commit simple.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-06-09-v2' into staging

QAPI patches for 2017-06-09

# gpg: Signature made Tue 20 Jun 2017 13:31:39 BST
# gpg: using RS

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2017-06-09-v2' into staging

QAPI patches for 2017-06-09

# gpg: Signature made Tue 20 Jun 2017 13:31:39 BST
# gpg: using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2017-06-09-v2: (41 commits)
tests/qdict: check more get_try_int() cases
console: use get_uint() for "head" property
i386/cpu: use get_uint() for "min-level"/"min-xlevel" properties
numa: use get_uint() for "size" property
pnv-core: use get_uint() for "core-pir" property
pvpanic: use get_uint() for "ioport" property
auxbus: use get_uint() for "addr" property
arm: use get_uint() for "mp-affinity" property
xen: use get_uint() for "max-ram-below-4g" property
pc: use get_uint() for "hpet-intcap" property
pc: use get_uint() for "apic-id" property
pc: use get_uint() for "iobase" property
acpi: use get_uint() for "pci-hole*" properties
acpi: use get_uint() for various acpi properties
acpi: use get_uint() for "acpi-pcihp-io*" properties
platform-bus: use get_uint() for "addr" property
bcm2835_fb: use {get, set}_uint() for "vcram-size" and "vcram-base"
aspeed: use {set, get}_uint() for "ram-size" property
pcihp: use get_uint() for "bsel" property
pc-dimm: make "size" property uint64
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

qapi: Remove visit_start_alternate() parameter promote_int

Before the previous commit, parameter promote_int = true made
visit_start_alternate() with an input visitor avoid QTYPE_QINT
variants and c

qapi: Remove visit_start_alternate() parameter promote_int

Before the previous commit, parameter promote_int = true made
visit_start_alternate() with an input visitor avoid QTYPE_QINT
variants and create QTYPE_QFLOAT variants instead. This was used
where QTYPE_QINT variants were invalid.

The previous commit fused QTYPE_QINT with QTYPE_QFLOAT, rendering
promote_int useless and unused.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170607163635.17635-8-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

Merge remote-tracking branch 'armbru/tags/pull-qapi-2017-05-04-v3' into staging

QAPI patches for 2017-05-04

# gpg: Signature made Tue 09 May 2017 03:16:12 AM EDT
# gpg: using RSA key

Merge remote-tracking branch 'armbru/tags/pull-qapi-2017-05-04-v3' into staging

QAPI patches for 2017-05-04

# gpg: Signature made Tue 09 May 2017 03:16:12 AM EDT
# gpg: using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* armbru/tags/pull-qapi-2017-05-04-v3: (28 commits)
qmp-shell: improve help
qmp-shell: don't show version greeting if unavailable
qmp-shell: Cope with query-commands error
qmp-shell: add -N option to skip negotiate
qmp-shell: add persistent command history
qobject-input-visitor: Catch misuse of end_struct vs. end_list
qapi: Document intended use of @name within alternate visits
qobject-input-visitor: Document full_name_nth()
qmp: Improve QMP dispatch error messages
sockets: Delete unused helper socket_address_crumple()
sockets: Limit SocketAddressLegacy to external interfaces
sockets: Rename SocketAddressFlat to SocketAddress
sockets: Rename SocketAddress to SocketAddressLegacy
qapi: New QAPI_CLONE_MEMBERS()
sockets: Prepare inet_parse() for flattened SocketAddress
sockets: Prepare vsock_parse() for flattened SocketAddress
test-qga: Actually test 0xff sync bytes
fdc-test: Avoid deprecated 'change' command
QemuOpts: Simplify qemu_opts_to_qdict()
block: Simplify bdrv_append_temp_snapshot() logic
...

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

show more ...

qapi: New QAPI_CLONE_MEMBERS()

QAPI_CLONE() returns a newly allocated QAPI object. Inconvenient when
we want to clone into an existing object. QAPI_CLONE_MEMBERS() does
exactly that.

Signed-off-b

qapi: New QAPI_CLONE_MEMBERS()

QAPI_CLONE() returns a newly allocated QAPI object. Inconvenient when
we want to clone into an existing object. QAPI_CLONE_MEMBERS() does
exactly that.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1493192202-3184-4-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-10-25' into staging

QAPI patches for 2016-10-25

# gpg: Signature made Tue 25 Oct 2016 16:56:27 BST
# gpg: using RSA k

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-10-25' into staging

QAPI patches for 2016-10-25

# gpg: Signature made Tue 25 Oct 2016 16:56:27 BST
# gpg: using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2016-10-25:
qdict: implement a qdict_crumple method for un-flattening a dict
qapi: don't pass two copies of TestInputVisitorData to tests
qapi: rename QmpOutputVisitor to QObjectOutputVisitor
qapi: rename QmpInputVisitor to QObjectInputVisitor
qapi: rename *qmp-*-visitor* to *qobject-*-visitor*
qapi: add trace events for visitor
trivial: Restore blank line in qapi-schema

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

qapi: rename *qmp-*-visitor* to *qobject-*-visitor*

The QMP visitors have no direct dependency on QMP. It is
valid to use them anywhere that one has a QObject. Rename them
to better reflect their fu

qapi: rename *qmp-*-visitor* to *qobject-*-visitor*

The QMP visitors have no direct dependency on QMP. It is
valid to use them anywhere that one has a QObject. Rename them
to better reflect their functionality as a generic QObject
to QAPI converter.

This is the first of three parts: rename the files. The next two
parts will rename C identifiers. The split is necessary to make git
rename detection work.

Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Split into file and identifier rename, two comments touched up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-07-06' into staging

QAPI patches for 2016-07-06

# gpg: Signature made Wed 06 Jul 2016 10:00:51 BST
# gpg: using RSA k

Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-07-06' into staging

QAPI patches for 2016-07-06

# gpg: Signature made Wed 06 Jul 2016 10:00:51 BST
# gpg: using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2016-07-06:
replay: Use new QAPI cloning
sockets: Use new QAPI cloning
qapi: Add new clone visitor
qapi: Add new visit_complete() function
tests: Factor out common code in qapi output tests
tests: Clean up test-string-output-visitor
qmp-output-visitor: Favor new visit_free() function
string-output-visitor: Favor new visit_free() function
qmp-input-visitor: Favor new visit_free() function
string-input-visitor: Favor new visit_free() function
opts-visitor: Favor new visit_free() function
qapi: Add new visit_free() function
qapi: Add parameter to visit_end_*
qemu-img: Don't leak errors when outputting JSON
qapi: Improve use of qmp/types.h

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

qapi: Add new clone visitor

We have a couple places in the code base that want to deep-clone
one QAPI object into another, and they were resorting to serializing
the struct out to QObject then repar

qapi: Add new clone visitor

We have a couple places in the code base that want to deep-clone
one QAPI object into another, and they were resorting to serializing
the struct out to QObject then reparsing it. A much more efficient
version can be done by adding a new clone visitor.

Since cloning is still relatively uncommon, expose the use of the
new visitor via a QAPI_CLONE() macro that takes care of type-punning
the underlying function pointer, rather than generating lots of
unused functions for types that won't be cloned. And yes, we're
relying on the compiler treating all pointers equally, even though
a strict C program cannot portably do so - but we're not the first
one in the qemu code base to expect it to work (hello, glib!).

The choice of adding a fourth visitor type deserves some explanation.
On the surface, the clone visitor is mostly an input visitor (it
takes arbitrary input - in this case, another QAPI object - and
creates a new QAPI object during the course of the visit). But
ever since commit da72ab0 consolidated enum visits based on the
visitor type, using VISITOR_INPUT would cause us to run
visit_type_str(), even though for cloning there is nothing to do
(we just copy the enum value across, without regards to its mapping
to strings). Also, since our input happens to be a QAPI object,
we can also satisfy the internal checks for VISITOR_OUTPUT. So in
the end, I settled with a new VISITOR_CLONE, and chose its value
such that many internal checks can use 'v->type & mask', sticking
to 'v->type == value' where the difference matters.

Note that we can only clone objects (including alternates) and lists,
not built-ins or enums. The visitor core hides integer width from
the actual visitor (since commit 04e070d), and as long as that's the
case, we can't clone top-level integers. Then again, those can
always be cloned by direct copy, since they are not objects with
deep pointers, so it's no real loss. And restricting cloning to
just objects and lists is cleaner than restricting it to non-integers.
As such, I documented that the clone visitor is for direct use only
by code internal to QAPI, and should not be used on incomplete objects
(other than a hack to work around the fact that we allow NULL in place
of "" in visit_type_str() in other output visitors). Note that as
written, the clone visitor will never fail on a complete object.

Scalars (including enums) not at the root of the clone copy just fine
with no additional effort while visiting the scalar, by virtue of a
g_memdup() each time we push another struct onto the stack. Cloning
a string requires deduplication of a pointer, which means it can also
provide the guarantee of an input visitor of never producing NULL
even when still accepting NULL in place of "" the way the QMP output
visitor does.

Cloning an 'any' type could be possible by incrementing the QObject
refcnt, but it's not obvious whether that is better than implementing
a QObject deep clone. So for now, we document it as unsupported,
and intentionally omit the .type_any() callback to let a developer
know their usage needs implementation.

Add testsuite coverage for several different clone situations, to
ensure that the code is working. I also tested that valgrind was
happy with the test.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-14-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

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