qapi: Rename QAPISchemaObjectType.variants to .branches

A previous commit narrowed the type of QAPISchemaObjectType.variants
from QAPISchemaVariants to QAPISchemaBranches. Rename it to
.branches.

qapi: Rename QAPISchemaObjectType.variants to .branches

A previous commit narrowed the type of QAPISchemaObjectType.variants
from QAPISchemaVariants to QAPISchemaBranches. Rename it to
.branches.

Same for .__init__() parameter @variants.

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

show more ...

qapi: Rename visitor parameter @variants to @alternatives

A previous commit narrowed the type of .visit_alternate_type()
parameter @variants from QAPISchemaVariants to QAPISchemaAlternatives.
Rename

qapi: Rename visitor parameter @variants to @alternatives

A previous commit narrowed the type of .visit_alternate_type()
parameter @variants from QAPISchemaVariants to QAPISchemaAlternatives.
Rename it to @alternatives.

One of them passes @alternatives to helper function
gen_visit_alternate(). Rename its @variants parameter to
@alternatives as well.

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

show more ...

qapi: Rename visitor parameter @variants to @branches

The previous commit narrowed the type of .visit_object_type()
parameter @variants from QAPISchemaVariants to QAPISchemaBranches.
Rename it to @b

qapi: Rename visitor parameter @variants to @branches

The previous commit narrowed the type of .visit_object_type()
parameter @variants from QAPISchemaVariants to QAPISchemaBranches.
Rename it to @branches.

Same for .visit_object_type_flat().

A few of these pass @branches to helper functions:
QAPISchemaGenRSTVisitor.visit_object_type() to ._nodes_for_members()
and ._nodes_for_variant_when(), and
QAPISchemaGenVisitVisitor.visit_object_type() to
gen_visit_object_members(). Rename the helpers' @variants parameters
to @branches as well.

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

show more ...

qapi: New QAPISchemaBranches, QAPISchemaAlternatives

QAPISchemaVariants represents either a union type's branches, or an
alternate type's alternatives. Much of its code is conditional on
which one

qapi: New QAPISchemaBranches, QAPISchemaAlternatives

QAPISchemaVariants represents either a union type's branches, or an
alternate type's alternatives. Much of its code is conditional on
which one it actually is.

Create QAPISchemaBranches for branches, and QAPISchemaAlternatives for
alternatives, both subtypes of QAPISchemaVariants.

Replace QAPISchemaVariants by one of them where possible. Keep it
only where we actually deal with either of them.

QAPISchemaVariants.__init__() takes @tag_name and @tag_member, where
exactly one must be None: @tag_name for alternatives, @tag_member for
branches. Let QAPISchemaBranches.__init__() take just @tag_name, and
QAPISchemaAlternatives.__init__() take just @tag_member.

A later patch will move the conditional code to the subtypes.

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

show more ...

qapi: Rename QAPISchemaObjectType.variants to .branches

A previous commit narrowed the type of QAPISchemaObjectType.variants
from QAPISchemaVariants to QAPISchemaBranches. Rename it to
.branches.

qapi: Rename QAPISchemaObjectType.variants to .branches

A previous commit narrowed the type of QAPISchemaObjectType.variants
from QAPISchemaVariants to QAPISchemaBranches. Rename it to
.branches.

Same for .__init__() parameter @variants.

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

show more ...

qapi: Rename visitor parameter @variants to @alternatives

A previous commit narrowed the type of .visit_alternate_type()
parameter @variants from QAPISchemaVariants to QAPISchemaAlternatives.
Rename

qapi: Rename visitor parameter @variants to @alternatives

A previous commit narrowed the type of .visit_alternate_type()
parameter @variants from QAPISchemaVariants to QAPISchemaAlternatives.
Rename it to @alternatives.

One of them passes @alternatives to helper function
gen_visit_alternate(). Rename its @variants parameter to
@alternatives as well.

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

show more ...

qapi: Rename visitor parameter @variants to @branches

The previous commit narrowed the type of .visit_object_type()
parameter @variants from QAPISchemaVariants to QAPISchemaBranches.
Rename it to @b

qapi: Rename visitor parameter @variants to @branches

The previous commit narrowed the type of .visit_object_type()
parameter @variants from QAPISchemaVariants to QAPISchemaBranches.
Rename it to @branches.

Same for .visit_object_type_flat().

A few of these pass @branches to helper functions:
QAPISchemaGenRSTVisitor.visit_object_type() to ._nodes_for_members()
and ._nodes_for_variant_when(), and
QAPISchemaGenVisitVisitor.visit_object_type() to
gen_visit_object_members(). Rename the helpers' @variants parameters
to @branches as well.

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

show more ...

qapi: New QAPISchemaBranches, QAPISchemaAlternatives

QAPISchemaVariants represents either a union type's branches, or an
alternate type's alternatives. Much of its code is conditional on
which one

qapi: New QAPISchemaBranches, QAPISchemaAlternatives

QAPISchemaVariants represents either a union type's branches, or an
alternate type's alternatives. Much of its code is conditional on
which one it actually is.

Create QAPISchemaBranches for branches, and QAPISchemaAlternatives for
alternatives, both subtypes of QAPISchemaVariants.

Replace QAPISchemaVariants by one of them where possible. Keep it
only where we actually deal with either of them.

QAPISchemaVariants.__init__() takes @tag_name and @tag_member, where
exactly one must be None: @tag_name for alternatives, @tag_member for
branches. Let QAPISchemaBranches.__init__() take just @tag_name, and
QAPISchemaAlternatives.__init__() take just @tag_member.

A later patch will move the conditional code to the subtypes.

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

show more ...

qapi: Start to elide redundant has_FOO in generated C

In QAPI, absent optional members are distinct from any present value.
We thus represent an optional schema member FOO as two C members: a
FOO wi

qapi: Start to elide redundant has_FOO in generated C

In QAPI, absent optional members are distinct from any present value.
We thus represent an optional schema member FOO as two C members: a
FOO with the member's type, and a bool has_FOO. Likewise for function
arguments.

However, has_FOO is actually redundant for a pointer-valued FOO, which
can be null only when has_FOO is false, i.e. has_FOO == !!FOO. Except
for arrays, where we a null FOO can also be a present empty array.

The redundant has_FOO are a nuisance to work with. Improve the
generator to elide them. Uses of has_FOO need to be replaced as
follows.

Tests of has_FOO become the equivalent comparison of FOO with null.
For brevity, this is commonly done by implicit conversion to bool.

Assignments to has_FOO get dropped.

Likewise for arguments to has_FOO parameters.

Beware: code may violate the invariant has_FOO == !!FOO before the
transformation, and get away with it. The above transformation can
then break things. Two cases:

* Absent: if code ignores FOO entirely when !has_FOO (except for
freeing it if necessary), even non-null / uninitialized FOO works.
Such code is known to exist.

* Present: if code ignores FOO entirely when has_FOO, even null FOO
works. Such code should not exist.

In both cases, replacing tests of has_FOO by FOO reverts their sense.
We have to fix the value of FOO then.

To facilitate review of the necessary updates to handwritten code, add
means to opt out of this change, and opt out for all QAPI schema
modules where the change requires updates to handwritten code. The
next few commits will remove these opt-outs in reviewable chunks, then
drop the means to opt out.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221104160712.3005652-5-armbru@redhat.com>

show more ...

scripts/qapi: minor delinting

Get isort and pylint tools passing again.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20220211183650.2946895-1-jsnow@redhat.com>
Reviewed-by: Markus Armbr

scripts/qapi: minor delinting

Get isort and pylint tools passing again.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20220211183650.2946895-1-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Comment explaining good-names-rgxs tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: Generalize enum member policy checking

The code to check enumeration value policy can see special feature
flag 'deprecated' in QEnumLookup member flags[value]. I want to make
feature flag 'un

qapi: Generalize enum member policy checking

The code to check enumeration value policy can see special feature
flag 'deprecated' in QEnumLookup member flags[value]. I want to make
feature flag 'unstable' visible there as well, so I can add policy for
it.

Instead of extending flags[], replace it by @special_features (a
bitset of QapiSpecialFeature), because that's how special features get
passed around elsewhere.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: John Snow <jsnow@redhat.com>
Message-Id: <20211028102520.747396-8-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

show more ...

qapi: Implement deprecated-input={reject,crash} for enum values

This copies the code implementing the policy from qapi/qmp-dispatch.c
to qapi/qobject-input-visitor.c. Tolerable, but if we acquire m

qapi: Implement deprecated-input={reject,crash} for enum values

This copies the code implementing the policy from qapi/qmp-dispatch.c
to qapi/qobject-input-visitor.c. Tolerable, but if we acquire more
copies, we should look into factoring them out.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Peter Krempa <pkrempa@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
Message-Id: <20211025042405.3762351-5-armbru@redhat.com>

show more ...

qapi: Simplify QAPISchemaIfCond's interface for generating C

QAPISchemaIfCond.cgen() is only ever used like

gen_if(ifcond.cgen())

and

gen_endif(ifcond.cgen())

Simplify to

ifcond.gen

qapi: Simplify QAPISchemaIfCond's interface for generating C

QAPISchemaIfCond.cgen() is only ever used like

gen_if(ifcond.cgen())

and

gen_endif(ifcond.cgen())

Simplify to

ifcond.gen_if()

and

ifcond.gen_endif()

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210831123809.1107782-2-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[Import statements tidied up with isort]

show more ...

qapi: introduce QAPISchemaIfCond.cgen()

Instead of building prepocessor conditions from a list of string, use
the result generated from QAPISchemaIfCond.cgen() and hide the
implementation details.

qapi: introduce QAPISchemaIfCond.cgen()

Instead of building prepocessor conditions from a list of string, use
the result generated from QAPISchemaIfCond.cgen() and hide the
implementation details.

Note: this patch introduces a minor regression, generating a redundant
pair of parenthesis. This is mostly fixed in a later patch in this
series ("qapi: replace if condition list with dict [..]")

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210804083105.97531-5-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: wrap Sequence[str] in an object

Mechanical change, except for a new assertion in
QAPISchemaEntity.ifcond().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <2021080

qapi: wrap Sequence[str] in an object

Mechanical change, except for a new assertion in
QAPISchemaEntity.ifcond().

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210804083105.97531-3-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Rebased with obvious conflicts, commit message adjusted]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: Replace List[str] with Sequence[str] for ifcond

It does happen to be a list (as of now), but we can describe it in more
general terms with no loss in accuracy to allow tuples and other
constru

qapi: Replace List[str] with Sequence[str] for ifcond

It does happen to be a list (as of now), but we can describe it in more
general terms with no loss in accuracy to allow tuples and other
constructs.

In the future, we can write "ifcond: Sequence[str] = ()" as a default
parameter, which we could not do safely with a Mutable type like a List.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210216021809.134886-2-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: type 'info' as Optional[QAPISourceInfo]

For everything typed so far, type this parameter as
Optional[QAPISourceInfo].

In the most generic case, QAPISchemaEntity's info field may be None to
re

qapi: type 'info' as Optional[QAPISourceInfo]

For everything typed so far, type this parameter as
Optional[QAPISourceInfo].

In the most generic case, QAPISchemaEntity's info field may be None to
represent types that come from built-in definitions. Although some
Entity types may not currently have any built-in definitions, it is not
easily possible to constrain the type except on an ad-hoc basis using
assertions.

It's easier and simpler, then, to just say it's always an Optional type.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210201193747.2169670-16-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi/gen: Replace ._begin_system_module()

QAPISchemaModularCVisitor._begin_system_module() is actually just for
the builtin module. Rename it to ._begin_builtin_module() and drop
its useless @name

qapi/gen: Replace ._begin_system_module()

QAPISchemaModularCVisitor._begin_system_module() is actually just for
the builtin module. Rename it to ._begin_builtin_module() and drop
its useless @name parameter.

Clarify conditionals in visit_module to make this clear.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210201193747.2169670-7-jsnow@redhat.com>

show more ...

qapi/types.py: remove one-letter variables

"John, if pylint told you to jump off a bridge, would you?"
Hey, if it looked like fun, I might.

Now that this file is clean, enable pylint checks on this

qapi/types.py: remove one-letter variables

"John, if pylint told you to jump off a bridge, would you?"
Hey, if it looked like fun, I might.

Now that this file is clean, enable pylint checks on this file.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201009161558.107041-34-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi/types.py: add type hint annotations

Annotations do not change runtime behavior.
This commit *only* adds annotations.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <e

qapi/types.py: add type hint annotations

Annotations do not change runtime behavior.
This commit *only* adds annotations.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Message-Id: <20201009161558.107041-33-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: Remove wildcard includes

Wildcard includes become hard to manage when refactoring and dealing
with circular dependencies with strictly typed mypy.

flake8 also flags each one as a warning, as

qapi: Remove wildcard includes

Wildcard includes become hard to manage when refactoring and dealing
with circular dependencies with strictly typed mypy.

flake8 also flags each one as a warning, as it is not smart enough to
know which names exist in the imported file.

Remove them and include things explicitly by name instead.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201009161558.107041-7-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: Prefer explicit relative imports

All of the QAPI include statements are changed to be package-aware, as
explicit relative imports.

A quirk of Python packages is that the name of the package e

qapi: Prefer explicit relative imports

All of the QAPI include statements are changed to be package-aware, as
explicit relative imports.

A quirk of Python packages is that the name of the package exists only
*outside* of the package. This means that to a module inside of the qapi
folder, there is inherently no such thing as the "qapi" package. The
reason these imports work is because the "qapi" package exists in the
context of the caller -- the execution shim, where sys.path includes a
directory that has a 'qapi' folder in it.

When we write "from qapi import sibling", we are NOT referencing the folder
'qapi', but rather "any package named qapi in sys.path". If you should
so happen to have a 'qapi' package in your path, it will use *that*
package.

When we write "from .sibling import foo", we always reference explicitly
our sibling module; guaranteeing consistency in *where* we are importing
these modules from.

This can be useful when working with virtual environments and packages
in development mode. In development mode, a package is installed as a
series of symlinks that forwards to your same source files. The problem
arises because code quality checkers will follow "import qapi.x" to the
"installed" version instead of the sibling file and -- even though they
are the same file -- they have different module paths, and this causes
cyclic import problems, false positive type mismatch errors, and more.

It can also be useful when dealing with hierarchical packages, e.g. if
we allow qemu.core.qmp, qemu.qapi.parser, etc.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20201009161558.107041-6-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: enable use of g_autoptr with QAPI types

Currently QAPI generates a type and function for free'ing it:

typedef struct QCryptoBlockCreateOptions QCryptoBlockCreateOptions;
void qapi_free_QC

qapi: enable use of g_autoptr with QAPI types

Currently QAPI generates a type and function for free'ing it:

typedef struct QCryptoBlockCreateOptions QCryptoBlockCreateOptions;
void qapi_free_QCryptoBlockCreateOptions(QCryptoBlockCreateOptions *obj);

This is used in the traditional manner:

QCryptoBlockCreateOptions *opts = NULL;

opts = g_new0(QCryptoBlockCreateOptions, 1);

....do stuff with opts...

qapi_free_QCryptoBlockCreateOptions(opts);

Since bumping the min glib to 2.48, QEMU has incrementally adopted the
use of g_auto/g_autoptr. This allows the compiler to run a function to
free a variable when it goes out of scope, the benefit being the
compiler can guarantee it is freed in all possible code ptahs.

This benefit is applicable to QAPI types too, and given the seriously
long method names for some qapi_free_XXXX() functions, is much less
typing. This change thus makes the code generator emit:

G_DEFINE_AUTOPTR_CLEANUP_FUNC(QCryptoBlockCreateOptions,
qapi_free_QCryptoBlockCreateOptions)

The above code example now becomes

g_autoptr(QCryptoBlockCreateOptions) opts = NULL;

opts = g_new0(QCryptoBlockCreateOptions, 1);

....do stuff with opts...

Note, if the local pointer needs to live beyond the scope holding the
variable, then g_steal_pointer can be used. This is useful to return the
pointer to the caller in the success codepath, while letting it be freed
in all error codepaths.

return g_steal_pointer(&opts);

The crypto/block.h header needs updating to avoid symbol clash now that
the g_autoptr support is a standard QAPI feature.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200723153845.2934357-1-berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

show more ...

qapi: Consistently put @features parameter right after @ifcond

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Bla

qapi: Consistently put @features parameter right after @ifcond

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200317115459.31821-14-armbru@redhat.com>

show more ...

qapi: Add feature flags to remaining definitions

In v4.1.0, we added feature flags just to struct types (commit
6a8c0b5102^..f3ed93d545), to satisfy an immediate need (commit
c9d4070991 "file-posix:

qapi: Add feature flags to remaining definitions

In v4.1.0, we added feature flags just to struct types (commit
6a8c0b5102^..f3ed93d545), to satisfy an immediate need (commit
c9d4070991 "file-posix: Add dynamic-auto-read-only QAPI feature"). In
v4.2.0, we added them to commands (commit 23394b4c39 "qapi: Add
feature flags to commands") to satisfy another immediate need (commit
d76744e65e "qapi: Allow introspecting fix for savevm's cooperation
with blockdev").

Add them to the remaining definitions: enumeration types, union types,
alternate types, and events.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200317115459.31821-13-armbru@redhat.com>

show more ...