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11 commits

Author SHA1 Message Date
liujunjie ea6ea4313d
qstring: Fix qstring_from_substr() not to provoke int overflow
qstring_from_substr() parameters @start and @end are of type int.
blkdebug_parse_filename(), blkverify_parse_filename(), nbd_parse_uri(),
and qstring_from_str() pass @end values of type size_t or ptrdiff_t.
Values exceeding INT_MAX get truncated, with possibly disastrous
results.

Such huge substrings seem unlikely, but we found one in a core dump,
where "info tlb" executed via QMP's human-monitor-command apparently
produced 35 GiB of output.

Fix by changing the parameters size_t.

Backports commit ad63c549ecd4af4a22a675a815edeb06b0e7bb6e from qemu
2018-08-02 21:21:51 -04:00
Marc-André Lureau f4b3c5d0bd
qobject: use a QObjectBase_ struct
By moving the base fields to a QObjectBase_, QObject can be a type
which also has a 'base' field. This allows writing a generic QOBJECT()
macro that will work with any QObject type, including QObject
itself. The container_of() macro ensures that the object to cast has a
QObjectBase_ base field, giving some type safety guarantees. QObject
must have no members but QObjectBase_ base, or else QOBJECT() breaks.

QObjectBase_ is not a typedef and uses a trailing underscore to make
it obvious it is not for normal use and to avoid potential abuse.

Backports commit 3d3eacaeccaab718ea0e2ddaa578bfae9e311c59 from qemu
2018-05-04 10:11:24 -04:00
Peter Xu a6ee6f1a87
qobject: introduce qobject_get_try_str()
A quick way to fetch string from qobject when it's a QString.

Backports commit b26ae1cb8eb0756524e322169138830b9b542311 from qemu
2018-03-20 11:10:03 -04:00
Peter Xu 6446b66dc7
qobject: introduce qstring_get_try_str()
The only difference from qstring_get_str() is that it allows the qstring
to be NULL. If so, NULL is returned.

Backports commit 775932020dd6bd7e9c1acc0d7779677d8b4c094c from qemu
2018-03-20 11:08:40 -04:00
Max Reitz 0c71b44d41
qapi: Remove qobject_to_X() functions
They are no longer needed now.

Backports commit cb51b976babf7ee16dc5eda4f2189d65b8b700a3 from qemu
2018-03-20 10:58:44 -04:00
Max Reitz b98c4d24d1
qapi: Add qobject_is_equal()
This generic function (along with its implementations for different
types) determines whether two QObjects are equal.

Backports commit b38dd678a21582e03ecd2dec76ccf8290455628a from qemu
2018-03-08 08:41:43 -05:00
Markus Armbruster bbc9bcbb44
Typedef the subtypes of QObject in qemu/typedefs.h, too
This renders many inclusions of qapi/qmp/q*.h superfluous. They'll be
dropped in the next few commits.

Backports commit 9f5c734d591e26186a71f9e36d752f4798df3672 from qemu
2018-03-07 12:29:31 -05:00
Eric Blake cc1d62568e
qobject: Simplify QObject
The QObject hierarchy is small enough, and unlikely to grow further
(since we only use it to map to JSON and already cover all JSON
types), that we can simplify things by not tracking a separate
vtable, but just inline the code element of the vtable QType
directly into QObject (renamed to type), and track a separate array
of destroy functions. We can drop qnull_destroy_obj() in the
process.

The remaining QObject subclasses must export their destructor.

This also has the nice benefit of moving the typename 'QType'
out of the way, so that the next patch can repurpose it for a
nicer name for 'qtype_code'.

The various objects are still the same size (so no change in cache
line pressure), but now have less indirection (although I didn't
bother benchmarking to see if there is a noticeable speedup, as
we don't have hard evidence that this was in a performance hotspot
in the first place).

A future patch could drop the refcnt size to 32 bits for a smaller
struct on 64-bit architectures, if desired (we have limits on the
largest JSON that we are willing to parse, and will probably never
need to take full advantage of a 64-bit refcnt).

Backports commit 55e1819c509b3d9c10a54678b9c585bbda13889e from qemu
2018-02-19 21:37:48 -05:00
xorstream fac6a66860 platform.h move #3 2017-01-21 00:13:21 +11:00
xorstream 1aeaf5c40d This code should now build the x86_x64-softmmu part 2. 2017-01-19 22:50:28 +11:00
Nguyen Anh Quynh 344d016104 import 2015-08-21 15:04:50 +08:00