By sticking the next pointer first, we don't need a union with
64-bit padding for smaller types. On 32-bit platforms, this
can reduce the size of uint8List from 16 bytes (or 12, depending
on whether 64-bit ints can tolerate 4-byte alignment) down to 8.
It has no effect on 64-bit platforms (where alignment still
dictates a 16-byte struct); but fewer anonymous unions is still
a win in my book.
It requires visit_next_list() to gain a size parameter, to know
what size element to allocate; comparable to the size parameter
of visit_start_struct().
I debated about going one step further, to allow for fewer casts,
by doing:
typedef GenericList GenericList;
struct GenericList {
GenericList *next;
};
struct FooList {
GenericList base;
Foo *value;
};
so that you convert to 'GenericList *' by '&foolist->base', and
back by 'container_of(generic, GenericList, base)' (as opposed to
the existing '(GenericList *)foolist' and '(FooList *)generic').
But doing that would require hoisting the declaration of
GenericList prior to inclusion of qapi-types.h, rather than its
current spot in visitor.h; it also makes iteration a bit more
verbose through 'foolist->base.next' instead of 'foolist->next'.
Note that for lists of objects, the 'value' payload is still
hidden behind a boxed pointer. Someday, it would be nice to do:
struct FooList {
FooList *next;
Foo value;
};
for one less level of malloc for each list element. This patch
is a step in that direction (now that 'next' is no longer at a
fixed non-zero offset within the struct, we can store more than
just a pointer's-worth of data as the value payload), but the
actual conversion would be a task for another series, as it will
touch a lot of code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-10-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
When reporting that an unvisited member remains at the end of an
input visit for a struct, we were using g_hash_table_find()
coupled with a callback function that always returns true, to
locate an arbitrary member of the hash table. But if all we
need is an arbitrary entry, we can get that from a single-use
iterator, without needing a tautological callback function.
Technically, our cast of &(GQueue *) to (void **) is not strict
C (while void * must be able to hold all other pointers, nothing
says a void ** has to be the same width or representation as a
GQueue **). The kosher way to write it would be the verbose:
void *tmp;
GQueue *any;
if (g_hash_table_iter_next(&iter, NULL, &tmp)) {
any = tmp;
But our code base (not to mention glib itself) already has other
cases of assuming that ALL pointers have the same width and
representation, where a compiler would have to go out of its way
to mis-compile our borderline behavior.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1455778109-6278-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
No backend was setting an error when ending the visit of a list or
implicit struct, or when moving to the next list node. Make the
callers a bit easier to follow by making this a part of the contract,
and removing the errp argument - callers can then unconditionally end
an object as part of cleanup without having to think about whether a
second error is dominated by a first, because there is no second
error.
A later patch will then tackle the larger task of splitting
visit_end_struct(), which can indeed set an error.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
visit_start_struct() and visit_type_enum() had a 'kind' argument
that was usually set to either the stringized version of the
corresponding qapi type name, or to NULL (although some clients
didn't even get that right). But nothing ever used the argument.
It's even hard to argue that it would be useful in a debugger,
as a stack backtrace also tells which type is being visited.
Therefore, drop the 'kind' argument as dead.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-22-git-send-email-eblake@redhat.com>
[Harmless rebase mistake cleaned up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
As explained in the previous patches, matching argument order of
'name, &value' to JSON's "name":value makes sense. However,
while the last two patches were easy with Coccinelle, I ended up
doing this one all by hand. Now all the visitor callbacks match
the main interface.
The compiler is able to enforce that all clients match the changed
interface in visitor-impl.h, even where two pointers are being
swapped, because only one of the two pointers is const (if that
were not the case, then C's looseness on treating 'char *' like
'void *' would have made review a bit harder).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-21-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The qapi builtin type 'int' is basically shorthand for the type
'int64'. In fact, since no visitor was providing the optional
type_int64() callback, visit_type_int64() was just always falling
back to type_int(), cementing the equivalence between the types.
However, some visitors are providing a type_uint64() callback.
For purposes of code consistency, it is nicer if all visitors
use the paired type_int64/type_uint64 names rather than the
mismatched type_int/type_uint64. So this patch just renames
the signed int callbacks in place, dropping the type_int()
callback as redundant, and a later patch will focus on the
unsigned int callbacks.
Add some FIXMEs to questionable reuse of errp in code touched
by the rename, while at it (the reuse works as long as the
callbacks don't modify value when setting an error, but it's not
a good example to set) - a later patch will then fix those.
No change in functionality here, although further cleanups are
in the pipeline.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-14-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The macro DO_UPCAST() is incorrectly named: it converts from a
parent class to a derived class (which is a downcast). Better,
and more consistent with some of the other qapi visitors, is
to use the container_of() macro through a to_FOO() helper. Names
like 'to_ov()' may be a bit short, but for a static helper it
doesn't hurt too much, and matches existing practice in files
like qmp-input-visitor.c.
Our current definition of container_of() is weaker than
DO_UPCAST(), in that it does not require the derived class to
have Visitor as its first member, but this does not hurt our
usage patterns in qapi visitors.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1454089805-5470-8-git-send-email-peter.maydell@linaro.org
None of the visitor callbacks would set an error when testing
if an optional field was present; make this part of the interface
contract by eliminating the errp argument.
The resulting generated code has a nice diff:
|- visit_optional(v, &has_fdset_id, "fdset-id", &err);
|- if (err) {
|- goto out;
|- }
|+ visit_optional(v, &has_fdset_id, "fdset-id");
| if (has_fdset_id) {
| visit_type_int(v, &fdset_id, "fdset-id", &err);
| if (err) {
| goto out;
| }
| }
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-9-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Not only it makes sense, but it gets rid of checkpatch warning:
WARNING: consider using qemu_strtosz in preference to strtosz
Also remove get rid of tabs to please checkpatch.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1442419377-9309-1-git-send-email-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These macros expand into error class enumeration constant, comma,
string. Unclean. Has been that way since commit 13f59ae.
The error class is always ERROR_CLASS_GENERIC_ERROR since the previous
commit.
Clean up as follows:
* Prepend every use of a QERR_ macro by ERROR_CLASS_GENERIC_ERROR, and
delete it from the QERR_ macro. No change after preprocessing.
* Rewrite error_set(ERROR_CLASS_GENERIC_ERROR, ...) into
error_setg(...). Again, no change after preprocessing.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
qemu_opt_del() already assumes that all QemuOpt instances contain
malloc'd name and value; but it had to cast away const because
opts_start_struct() was doing its own thing and using static storage
instead. By using the correct type and malloced strings everywhere, the
usage of this struct becomes clearer.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Leandro Dorileo <l@dorileo.org>
Signed-off-by: Chunyan Liu <cyliu@suse.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Semantics of end_optional() differ subtly from the other end_FOO()
callbacks: when start_FOO() succeeds, the matching end_FOO() gets
called regardless of what happens in between. end_optional() gets
called only when everything in between succeeds as well. Entirely
undocumented, like all of the visitor API.
The only user of Visitor Callback end_optional() never did anything,
and was removed in commit 9f9ab46.
I'm about to clean up error handling in the generated visitor code,
and end_optional() is in my way. No users mean no test cases, and
making non-trivial cleanup transformations without test cases doesn't
strike me as a good idea.
Drop end_optional(), and rename start_optional() to optional(). We
can always go back to a pair of callbacks when we have an actual need.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
strtosz_suffix() might return negative error, this patch fixes
the error handling.
This patch also changes to handle error in the if statement
rather than handle success specially, this will make this use
of strtosz_suffix consistent with all other uses.
Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Argument is null when visiting an unboxed struct. I can't see such a
visit in the current code. Fix it anyway.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Prevent mistyped command line options from incurring high memory and CPU
usage at startup. 64K elements in a range should be enough for everyone
(TM).
The OPTS_VISITOR_RANGE_MAX macro is public so that unit tests can
construct corner cases with it.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
When a well-formed range value, bounded by unsigned integers, is
encountered while processing a repeated option, enter LM_UNSIGNED_INTERVAL
and return the low bound.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Simplify the code in preparation for the next patch.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
When a well-formed range value, bounded by signed integers, is encountered
while processing a repeated option, enter LM_SIGNED_INTERVAL and return
the low bound.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The new modes are equal-rank, exclusive alternatives of LM_IN_PROGRESS.
Teach opts_next_list(), opts_type_int() and opts_type_uint64() to handle
them.
Also enumerate explicitly what functions are valid to call in what modes:
- opts_next_list() is valid to call while flattening a range,
- opts_end_list(): ditto,
- lookup_scalar() is invalid to call during flattening; generated qapi
traversal code must continue asking for the same kind of signed/unsigned
list element until the interval is fully flattened,
- processed(): ditto.
List mode restrictions are always formulated in positive / inclusive
sense. The restrictions for lookup_scalar() and processed() are
automatically satisfied by current qapi traversals if the schema to build
is compatible with OptsVisitor.
The new list modes are not entered yet.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
We're going to need more state while processing a list of repeated
options. This change eliminates "repeated_opts_first" and adds a new state
variable:
list_mode repeated_opts repeated_opts_first
-------------- ------------- -------------------
LM_NONE NULL false
LM_STARTED non-NULL true
LM_IN_PROGRESS non-NULL false
Additionally, it is documented that lookup_scalar() and processed(), both
called by opts_type_XXX(), are invalid in LM_STARTED -- generated qapi
code calls opts_next_list() to allocate the very first link before trying
to parse a scalar into it. List mode restrictions are expressed in
positive / inclusive form.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
The file is only including error.h and qerror.h. Prefer explicit
inclusion of whatever files are needed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
valgrind report:
==24534== 232 bytes in 2 blocks are definitely lost in loss record 1,245 of 1,601
==24534== at 0x4824F20: malloc (vg_replace_malloc.c:236)
==24534== by 0x293C88: malloc_and_trace (vl.c:2281)
==24534== by 0x489AD99: ??? (in /lib/libglib-2.0.so.0.2400.1)
==24534== by 0x489B23B: g_malloc0 (in /lib/libglib-2.0.so.0.2400.1)
==24534== by 0x2B4EFC: opts_visitor_new (opts-visitor.c:376)
==24534== by 0x29DEA5: net_client_init (net.c:708)
==24534== by 0x29E6C7: net_init_client (net.c:966)
==24534== by 0x2C2179: qemu_opts_foreach (qemu-option.c:1114)
==24534== by 0x29E85B: net_init_clients (net.c:1008)
==24534== by 0x296F40: main (vl.c:3463)
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This visitor supports parsing
-option [type=]discriminator[,optarg1=val1][,optarg2=val2][,...]
style QemuOpts objects into "native" C structures. After defining the type
tree in the qapi schema (see below), a root type traversal with this
visitor linked to the underlying QemuOpts object will build the "native" C
representation of the option.
The type tree in the schema, corresponding to an option with a
discriminator, must have the following structure:
struct
scalar member for non-discriminated optarg 1 [*]
list for repeating non-discriminated optarg 2 [*]
wrapper struct
single scalar member
union
struct for discriminator case 1
scalar member for optarg 3 [*]
list for repeating optarg 4 [*]
wrapper struct
single scalar member
scalar member for optarg 5 [*]
struct for discriminator case 2
...
The "type" optarg name is fixed for the discriminator role. Its schema
representation is "union of structures", and each discriminator value must
correspond to a member name in the union.
If the option takes no "type" descriminator, then the type subtree rooted
at the union must be absent from the schema (including the union itself).
Optarg values can be of scalar types str / bool / integers / size.
Members marked with [*] may be defined as optional in the schema,
describing an optional optarg.
Repeating an optarg is supported; its schema representation must be "list
of structure with single mandatory scalar member". If an optarg is not
described as repeating in the schema (ie. it is defined as a scalar field
instead of a list), its last occurrence will take effect. Ordering between
differently named optargs is not preserved.
A mandatory list (or an optional one which is reported to be available),
corresponding to a repeating optarg, has at least one element after
successful parsing.
v1->v2:
- Update opts_type_size() prototype to uint64_t.
- Add opts_type_uint64() for options needing the full uint64_t range.
(Internals could be extracted to "cutils.c".)
- Allow negative values in opts_type_int().
- Rebase to nested Makefiles.
v2->v3:
- Factor opts_visitor_insert() out of opts_start_struct() and call it
separately for opts_root->id if there's any.
- Don't require non-negative values in opts_type_int()'s error message.
- g_malloc0() may return NULL for zero-sized requests. Support empty
structures by requesting 1 byte for them instead.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Eric Blake
Peter Maydell
Marc-André Lureau
Markus Armbruster
Chunyan Liu
Amos Kong
Laszlo Ersek
Paolo Bonzini
Stefan Weil