qemu/tests
Eric Blake a15fcc3cf6 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>
2016-07-06 10:52:04 +02:00
..
acpi-test-data tests: add APIC.cphp and DSDT.cphp blobs 2016-07-04 19:43:33 +03:00
docker tests/docker: build all targets in test-clang 2016-06-08 15:19:30 +08:00
guest-debug tests/guest-debug: introduce basic gdbstub tests 2015-12-17 13:37:15 +00:00
image-fuzzer tests: Use Python 2.6 "except E as ..." syntax 2016-02-08 17:29:54 +01:00
libqos libqos: add qvirtqueue_cleanup() 2016-06-20 11:44:12 +01:00
multiboot tests/multiboot: Add test for modules 2015-01-26 12:22:44 +01:00
qapi-schema qapi: Allow anonymous base for flat union 2016-03-18 10:29:26 +01:00
qemu-iotests crypto: fix handling of iv generator hash defaults 2016-07-04 10:46:59 +01:00
rocker rocker: tests: don't need to specify master/self when setting vlans 2015-07-07 13:13:22 +01:00
tcg Fix some typos found by codespell 2016-05-18 15:04:27 +03:00
vmstate-static-checker-data tests: vmstate static checker: add size mismatch inside substructure 2014-06-23 19:14:52 +02:00
.gitignore qapi: Add new clone visitor 2016-07-06 10:52:04 +02:00
ac97-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ahci-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
bios-tables-test.c tests: acpi: add CPU hotplug testcase 2016-07-04 16:49:34 +03:00
boot-order-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
boot-sector.c all: Clean up includes 2016-02-23 12:43:05 +00:00
boot-sector.h tests: add pxe e1000 and virtio-pci tests 2016-02-16 12:05:18 +02:00
check-block.sh qemu-iotests: make check-block.sh work on out-of-tree builds 2016-01-07 21:30:16 +01:00
check-qdict.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qfloat.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qint.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qjson.c qapi: Improve use of qmp/types.h 2016-07-06 10:52:03 +02:00
check-qlist.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qnull.c qapi: Add new visit_complete() function 2016-07-06 10:52:04 +02:00
check-qom-interface.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qom-proplist.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
check-qstring.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
crypto-tls-x509-helpers.c tests: Clean up includes 2016-02-16 14:29:27 +00:00
crypto-tls-x509-helpers.h crypto: add sanity checking of TLS x509 credentials 2015-09-15 15:05:09 +01:00
device-introspect-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
display-vga-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
drive_del-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ds1338-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
e1000-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
e1000e-test.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
eepro100-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
endianness-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
es1370-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
fdc-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
fw_cfg-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
hd-geo-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
i440fx-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
i82801b11-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ide-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
intel-hda-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
io-channel-helpers.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
io-channel-helpers.h io: add QIOChannelSocket class 2015-12-18 12:18:31 +00:00
ioh3420-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ipmi-bt-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ipmi-kcs-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ipoctal232-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
ivshmem-test.c os-posix: include sys/mman.h 2016-06-16 18:39:03 +02:00
libqtest.c tests: fix libqtest socket timeouts 2016-06-16 09:50:07 +05:30
libqtest.h all: Clean up includes 2016-02-23 12:43:05 +00:00
m48t59-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
Makefile.include qapi: Add new clone visitor 2016-07-06 10:52:04 +02:00
ne2000-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
nvme-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
pc-cpu-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
pcnet-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
pkix_asn1_tab.c tests: Clean up includes 2016-02-16 14:29:27 +00:00
postcopy-test.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
prom-env-test.c ppc / sparc: Add a tester for checking whether OpenBIOS runs successfully 2016-06-17 15:57:59 +10:00
pvpanic-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
pxe-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
q35-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
qemu-iotests-quick.sh qemu-iotests: Speed up make check-block 2015-01-13 11:47:55 +00:00
qht-bench.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
qom-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
rcutorture.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
rtc-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
rtl8139-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
spapr-phb-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
tco-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-aio.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-base64.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-bitops.c bitops.h: Implement half-shuffle and half-unshuffle ops 2016-06-17 15:23:51 +01:00
test-blockjob-txn.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-clone-visitor.c qapi: Add new clone visitor 2016-07-06 10:52:04 +02:00
test-coroutine.c trivial patches for 2016-06-07 2016-06-07 16:34:45 +01:00
test-crypto-afsplit.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-block.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-cipher.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-crypto-hash.c crypto: implement sha224, sha384, sha512 and ripemd160 hashes 2016-07-04 15:52:36 +01:00
test-crypto-ivgen.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-pbkdf.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-secret.c crypto: remove temp files on completion of secrets test 2016-06-13 12:41:17 +01:00
test-crypto-tlscredsx509.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-tlssession.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-crypto-xts.c crypto: rename OUT to out in xts test to avoid clash on MinGW 2016-07-04 10:46:59 +01:00
test-cutils.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-filter-mirror.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-filter-redirector.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
test-hbitmap.c hbitmap: Use DIV_ROUND_UP 2016-06-07 18:19:25 +03:00
test-int128.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-io-channel-buffer.c tests: Clean up includes 2016-02-16 14:29:27 +00:00
test-io-channel-command.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-io-channel-file.c include/qemu/osdep.h: Don't include qapi/error.h 2016-03-22 22:20:15 +01:00
test-io-channel-socket.c socket: unlink unix socket on remove 2016-06-29 16:49:41 +02:00
test-io-channel-tls.c tests: Clean up includes 2016-02-16 14:29:27 +00:00
test-io-task.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-iov.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-logging.c log: Permit -dfilter 0..0xffffffffffffffff 2016-07-04 16:49:33 +03:00
test-mul64.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-netfilter.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-opts-visitor.c opts-visitor: Favor new visit_free() function 2016-07-06 10:52:04 +02:00
test-qdev-global-props.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-qdist.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
test-qemu-opts.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-qga.c tests: start a /qga/guest-exec test 2016-06-07 11:25:06 -05:00
test-qht-par.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
test-qht.c clean-includes: run it once more 2016-06-16 18:39:03 +02:00
test-qmp-commands.c qmp-input-visitor: Favor new visit_free() function 2016-07-06 10:52:04 +02:00
test-qmp-event.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-qmp-input-strict.c qmp-input-visitor: Favor new visit_free() function 2016-07-06 10:52:04 +02:00
test-qmp-input-visitor.c qmp-input-visitor: Favor new visit_free() function 2016-07-06 10:52:04 +02:00
test-qmp-output-visitor.c qapi: Add new visit_complete() function 2016-07-06 10:52:04 +02:00
test-rcu-list.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-rfifolock.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-string-input-visitor.c string-input-visitor: Favor new visit_free() function 2016-07-06 10:52:04 +02:00
test-string-output-visitor.c qapi: Add new visit_complete() function 2016-07-06 10:52:04 +02:00
test-thread-pool.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-throttle.c trivial patches for 2016-06-07 2016-06-07 16:34:45 +01:00
test-timed-average.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-visitor-serialization.c qapi: Add new visit_complete() function 2016-07-06 10:52:04 +02:00
test-vmstate.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-write-threshold.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-x86-cpuid.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
test-xbzrle.c util: move declarations out of qemu-common.h 2016-03-22 22:20:17 +01:00
tmp105-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
tpci200-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
usb-hcd-ehci-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
usb-hcd-ohci-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
usb-hcd-uhci-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
usb-hcd-xhci-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
vhost-user-bridge.c pc, pci, virtio: new features, cleanups, fixes 2016-06-17 11:25:46 +01:00
vhost-user-test.c vhost-user-test: fix g_cond_wait_until compat implementation 2016-06-29 16:49:40 +02:00
virtio-9p-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
virtio-balloon-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
virtio-blk-test.c Error reporting patches for 2016-06-20 2016-06-20 16:19:18 +01:00
virtio-console-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00
virtio-net-test.c Error reporting patches for 2016-06-20 2016-06-20 16:19:18 +01:00
virtio-rng-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
virtio-scsi-test.c Error reporting patches for 2016-06-20 2016-06-20 16:19:18 +01:00
virtio-serial-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
vmxnet3-test.c tests: Remove unnecessary glib.h includes 2016-06-07 18:19:24 +03:00
wdt_ib700-test.c coccinelle: Remove unnecessary variables for function return value 2016-06-20 16:38:13 +02:00