Commit 7ce106a rendered QAPISchemaObjectType.c_name() redundant,
since it now does nothing more than delegate to its superclass.
However, rather than deleting it, we can restore part of the
assertion that was removed in that commit, to prove that we never
emit the empty type directly in generated code, but rather
special-case it as a built-in that makes other aspects of code
generation easier to reason about.
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-4-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We were previously enforcing that all flat union branches were
found in the corresponding enum, but not that all enum values
were covered by branches. The resulting generated code would
abort() if the user passes the uncovered enum value.
We don't automatically treat non-present branches in a flat
union as empty types, for symmetry with simple unions (there,
the enum type is generated from the list of all branches, so
there is no way to omit a branch but still have it be part of
the union).
A later patch will add shorthand so that branches that are empty
in flat unions can be declared as 'branch':{} instead of
'branch':'Empty', to avoid the need for an otherwise useless
explicit empty type. [Such shorthand for simple unions is a bit
harder to justify, since we would still have to generate a
wrapper type that parses 'data':{}, rather than truly being an
empty branch with no additional siblings to the 'type' member.]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-3-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that the generator supports it, we might as well use an
anonymous base rather than breaking out a single-use Base
structure, for all three of our current QMP flat unions.
Oddly enough, this change does not affect the resulting
introspection output (because we already inline the members of
a base type into an object, and had no independent use of the
base type reachable from a command).
The case_whitelist now has to list the name of an implicit
type; which is not too bad (consider it a feature if it makes
it harder for developers to make the whitelist grow :)
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than requiring all flat unions to explicitly create
a separate base struct, we can allow the qapi schema to specify
the common members via an inline dictionary. This is similar to
how commands can specify an inline anonymous type for its 'data'.
We already have several struct types that only exist to serve as
a single flat union's base; the next commit will clean them up.
In particular, this patch's change to the BlockdevOptions example
in qapi-code-gen.txt will actually be done in the real QAPI schema.
Now that anonymous bases are legal, we need to rework the
flat-union-bad-base negative test (as previously written, it
forms what is now valid QAPI; tweak it to now provide coverage
of a new error message path), and add a positive test in
qapi-schema-test to use an anonymous base (making the integer
argument optional, for even more coverage).
Note that this patch only allows anonymous bases for flat unions;
simple unions are already enough syntactic sugar that we do not
want to burden them further. Meanwhile, while it would be easy
to also allow an anonymous base for structs, that would be quite
redundant, as the members can be put right into the struct
instead.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Simple unions were carrying a special case that hid their 'data'
QMP member from the resulting C struct, via the hack method
QAPISchemaObjectTypeVariant.simple_union_type(). But by using
the work we started by unboxing flat union and alternate
branches, coupled with the ability to visit the members of an
implicit type, we can now expose the simple union's implicit
type in qapi-types.h:
| struct q_obj_ImageInfoSpecificQCow2_wrapper {
| ImageInfoSpecificQCow2 *data;
| };
|
| struct q_obj_ImageInfoSpecificVmdk_wrapper {
| ImageInfoSpecificVmdk *data;
| };
...
| struct ImageInfoSpecific {
| ImageInfoSpecificKind type;
| union { /* union tag is @type */
| void *data;
|- ImageInfoSpecificQCow2 *qcow2;
|- ImageInfoSpecificVmdk *vmdk;
|+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2;
|+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk;
| } u;
| };
Doing this removes asymmetry between QAPI's QMP side and its
C side (both sides now expose 'data'), and means that the
treatment of a simple union as sugar for a flat union is now
equivalent in both languages (previously the two approaches used
a different layer of dereferencing, where the simple union could
be converted to a flat union with equivalent C layout but
different {} on the wire, or to an equivalent QMP wire form
but with different C representation). Using the implicit type
also lets us get rid of the simple_union_type() hack.
Of course, now all clients of simple unions have to adjust from
using su->u.member to using su->u.member.data; while this touches
a number of files in the tree, some earlier cleanup patches
helped minimize the change to the initialization of a temporary
variable rather than every single member access. The generated
qapi-visit.c code is also affected by the layout change:
|@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member
| }
| switch (obj->type) {
| case IMAGE_INFO_SPECIFIC_KIND_QCOW2:
|- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err);
|+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err);
| break;
| case IMAGE_INFO_SPECIFIC_KIND_VMDK:
|- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err);
|+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err);
| break;
| default:
| abort();
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that we are always bulk-initializing a QAPI C struct to 0
(whether by g_malloc0() or by 'Type arg = {0};'), we no longer
have any clients of c_null() in the generator for per-element
initialization. This patch is easy enough to revert if we find
a use in the future, but in the present, get rid of the dead code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-12-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit 82ca8e46 noticed that we had multiple implementations of
visiting every member of a struct, and consolidated it into
gen_visit_fields() (now gen_visit_members()) with enough
parameters to cater to slight differences between the clients.
But recent exposure of implicit types has meant that we are now
down to a single use of that method, so we can clean up the
unused conditionals and just inline it into the remaining
caller: gen_visit_object_members().
Likewise, gen_err_check() no longer needs optional parameters,
as the lone use of non-defaults was via gen_visit_members().
No change to generated code.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We already have several places that want to visit all the members
of an implicit object within a larger context (simple union variant,
event with anonymous data, command with anonymous arguments struct);
and will be adding another one soon (the ability to declare an
anonymous base for a flat union). Having a C struct declared for
these implicit types, along with a visit_type_FOO_members() helper
function, will make for fewer special cases in our generator.
We do not, however, need qapi_free_FOO() or visit_type_FOO()
functions for implicit types, because they should not be used
directly outside of the generated code. This is done by adding a
conditional in visit_object_type() for both qapi-types.py and
qapi-visit.py based on the object name. The comparison of
"name.startswith('q_')" is a bit hacky (it's basically duplicating
what .is_implicit() already uses), but beats changing the signature
of the visit_object_type() callback to pass a new 'implicit' flag.
The hack should be temporary: we are considering adding a future
patch that consolidates the narrow visit_object_type(..., base,
local_members, variants) and visit_object_type_flat(...,
all_members, variants) [where different sets of information are
already broken out, and the QAPISchemaObjectType is no longer
available] into a broader visit_object_type(obj_type) [where the
visitor can query the needed fields from obj_type directly].
Also, now that we WANT to output C code for implicits, we no longer
need the visit_needed() filter, leaving 'q_empty' as the only object
still needing a special case. Remember, 'q_empty' is the only
built-in generated object, which means that without a special case
it would be emitted in multiple files (the main qapi-types.h and in
qga-qapi-types.h) causing compilation failure due to redefinition.
But since it has no members, it's easier to just avoid an attempt to
visit that particular type; since gen_object() is called recursively,
we also prime the objects_seen set to cover any recursion into the
empty type.
The patch relies on the changed naming of implicit types in the
previous patch. It is a bit unfortunate that the generated struct
names and visit_type_FOO_members() don't match normal naming
conventions, but it's not too bad, since they will only be used in
generated code.
The generated code grows substantially in size: the implicit
'-wrapper' types must be emitted in qapi-types.h before any union
can include an unboxed member of that type. Arguably, the '-args'
types could be emitted in a private header for just qapi-visit.c
and qmp-marshal.c, rather than polluting qapi-types.h; but adding
complexity to the generator to split the output location according
to role doesn't seem worth the maintenance costs.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-6-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The original choice of ':obj-' as the prefix for implicit types
made it obvious that we weren't going to clash with any user-defined
names, which cannot contain ':'. But now we want to create structs
for implicit types, to get rid of special cases in the generators,
and our use of ':' in implicit names needs a tweak to produce valid
C code.
We could transliterate ':' to '_', except that C99 mandates that
"identifiers that begin with an underscore are always reserved for
use as identifiers with file scope in both the ordinary and tag name
spaces". So it's time to change our naming convention: we can
instead use the 'q_' prefix that we reserved for ourselves back in
commit 9fb081e0. Technically, since we aren't planning on exposing
the empty type in generated code, we could keep the name ':empty',
but renaming it to 'q_empty' makes the check for startswith('q_')
cover all implicit types, whether or not code is generated for them.
As long as we don't declare 'empty' or 'obj' ticklish, it shouldn't
clash with c_name() prepending 'q_' to the user's ticklish names.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
QAPISchemaType.c_type() is a bit awkward: it takes two optional
boolean flags is_param and is_unboxed, and they should never both
be True.
Add a new method for each of the flags, and drop the flags from
c_type().
Most callers pass no flags; they remain unchanged.
One caller passes is_param=True; call the new .c_param_type()
instead.
One caller passes is_unboxed=True, except for simple union types.
This is actually an ugly special case that will go away soon, so
until then, we now have to call either .c_type() or the new
.c_unboxed_type(). Tolerable in the interim.
It requires slightly more Python, but is arguably easier to read.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
C types and JSON objects don't have fields, but members. We
shouldn't gratuitously invent terminology. This patch is a
strict renaming of generator code internals (including testsuite
comments), before later patches rename C interfaces.
No change to generated code with this patch.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Lowercase them.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
All lowercase, use-dash instead of CamelCase.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
There's no reason to do two malloc's for an alternate type visiting
a QAPI struct; let's just inline the struct directly as the C union
branch of the struct.
Surprisingly, no clients were actually using the struct member prior
to this patch outside of the testsuite; an earlier patch in the series
added some testsuite coverage to make the effect of this patch more
obvious.
In qapi.py, c_type() gains a new is_unboxed flag to control when we
are emitting a C struct unboxed within the context of an outer
struct (different from our other two modes of usage with no flags
for normal local variable declarations, and with is_param for adding
'const' in a parameter list). I don't know if there is any more
pythonic way of collapsing the two flags into a single parameter,
as we never have a caller setting both flags at once.
Ultimately, we want to also unbox branches for QAPI unions, but as
that touches a lot more client code, it is better as separate
patches. But since unions and alternates share gen_variants(), I
had to hack in a way to test if we are visiting an alternate type
for setting the is_unboxed flag: look for a non-object branch.
This works because alternates have at least two branches, with at
most one object branch, while unions have only object branches.
The hack will go away in a later patch.
The generated code difference to qapi-types.h is relatively small:
| struct BlockdevRef {
| QType type;
| union { /* union tag is @type */
| void *data;
|- BlockdevOptions *definition;
|+ BlockdevOptions definition;
| char *reference;
| } u;
| };
The corresponding spot in qapi-visit.c calls visit_type_FOO(), which
first calls visit_start_struct() to allocate or deallocate the member
and handle a layer of {} from the JSON stream, then visits the
members. To peel off the indirection and the memory management that
comes with it, we inline this call, then suppress allocation /
deallocation by passing NULL to visit_start_struct(), and adjust the
member visit:
| switch ((*obj)->type) {
| case QTYPE_QDICT:
|- visit_type_BlockdevOptions(v, name, &(*obj)->u.definition, &err);
|+ visit_start_struct(v, name, NULL, 0, &err);
|+ if (err) {
|+ break;
|+ }
|+ visit_type_BlockdevOptions_fields(v, &(*obj)->u.definition, &err);
|+ error_propagate(errp, err);
|+ err = NULL;
|+ visit_end_struct(v, &err);
| break;
| case QTYPE_QSTRING:
| visit_type_str(v, name, &(*obj)->u.reference, &err);
The visit of non-object fields is unchanged.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-13-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The whole point of an alternate is to allow some type-safety while
still accepting more than one JSON type. Meanwhile, the 'any'
type exists to bypass type-safety altogether. The two are
incompatible: you can't accept every type, and still tell which
branch of the alternate to use for the parse; fix this to give a
sane error instead of a Python stack trace.
Note that other types that can't be alternate members are caught
earlier, by check_type().
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-4-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Empty unions serve no purpose, and while we compile with gcc
which permits them, strict C99 forbids them. We happen to inject
a dummy 'void *data' member into the C unions that represent QAPI
unions and alternates, but we want to get rid of that member (it
pollutes the namespace for no good reason), which would leave us
with an empty union if the user didn't provide any branches. While
empty structs make sense in QAPI, empty unions don't add any
expressiveness to the QMP language. So prohibit them at parse
time. Update the documentation and testsuite to match.
Note that the documentation already mentioned that alternates
should have "two or more JSON data types"; so this also fixes
the code to enforce that. However, we have existing uses of a
union type with only one branch, so the 2-or-more strictness
is intentionally limited to alternates.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit 86f4b687 broke compilation on MIPS and SPARC, which have a
preprocessor pollution of '#define mips 1' and '#define sparc 1',
respectively. Treat it the same way as we do for the pollution with
'unix', so that QMP remains backwards compatible and only the C code
needs to use the alternative 'q_mips', 'q_sparc' spelling.
CC: James Hogan <james.hogan@imgtec.com>
CC: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Eric Blake <eblake@redhat.com>
Tested-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
JSON uses "name":value, but many of our visitor interfaces were
called with visit_type_FOO(v, &value, name, errp). This can be
a bit confusing to have to mentally swap the parameter order to
match JSON order. It's particularly bad for visit_start_struct(),
where the 'name' parameter is smack in the middle of the
otherwise-related group of 'obj, kind, size' parameters! It's
time to do a global swap of the parameter ordering, so that the
'name' parameter is always immediately after the Visitor argument.
Additional reason in favor of the swap: the existing include/qjson.h
prefers listing 'name' first in json_prop_*(), and I have plans to
unify that file with the qapi visitors; listing 'name' first in
qapi will minimize churn to the (admittedly few) qjson.h clients.
Later patches will then fix docs, object.h, visitor-impl.h, and
those clients to match.
Done by first patching scripts/qapi*.py by hand to make generated
files do what I want, then by running the following Coccinelle
script to affect the rest of the code base:
$ spatch --sp-file script `git grep -l '\bvisit_' -- '**/*.[ch]'`
I then had to apply some touchups (Coccinelle insisted on TAB
indentation in visitor.h, and botched the signature of
visit_type_enum() by rewriting 'const char *const strings[]' to
the syntactically invalid 'const char*const[] strings'). The
movement of parameters is sufficient to provoke compiler errors
if any callers were missed.
// Part 1: Swap declaration order
@@
type TV, TErr, TObj, T1, T2;
identifier OBJ, ARG1, ARG2;
@@
void visit_start_struct
-(TV v, TObj OBJ, T1 ARG1, const char *name, T2 ARG2, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
{ ... }
@@
type bool, TV, T1;
identifier ARG1;
@@
bool visit_optional
-(TV v, T1 ARG1, const char *name)
+(TV v, const char *name, T1 ARG1)
{ ... }
@@
type TV, TErr, TObj, T1;
identifier OBJ, ARG1;
@@
void visit_get_next_type
-(TV v, TObj OBJ, T1 ARG1, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, TErr errp)
{ ... }
@@
type TV, TErr, TObj, T1, T2;
identifier OBJ, ARG1, ARG2;
@@
void visit_type_enum
-(TV v, TObj OBJ, T1 ARG1, T2 ARG2, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
{ ... }
@@
type TV, TErr, TObj;
identifier OBJ;
identifier VISIT_TYPE =~ "^visit_type_";
@@
void VISIT_TYPE
-(TV v, TObj OBJ, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, TErr errp)
{ ... }
// Part 2: swap caller order
@@
expression V, NAME, OBJ, ARG1, ARG2, ERR;
identifier VISIT_TYPE =~ "^visit_type_";
@@
(
-visit_start_struct(V, OBJ, ARG1, NAME, ARG2, ERR)
+visit_start_struct(V, NAME, OBJ, ARG1, ARG2, ERR)
|
-visit_optional(V, ARG1, NAME)
+visit_optional(V, NAME, ARG1)
|
-visit_get_next_type(V, OBJ, ARG1, NAME, ERR)
+visit_get_next_type(V, NAME, OBJ, ARG1, ERR)
|
-visit_type_enum(V, OBJ, ARG1, ARG2, NAME, ERR)
+visit_type_enum(V, NAME, OBJ, ARG1, ARG2, ERR)
|
-VISIT_TYPE(V, OBJ, NAME, ERR)
+VISIT_TYPE(V, NAME, OBJ, ERR)
)
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-19-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
All other successful clients of visit_start_struct() were paired
with an unconditional visit_end_struct(); but the generated
code for events was relying on qmp_output_visitor_cleanup() to
work on an incomplete visit. Alter the code to guarantee that
the struct is completed, which will make a future patch to
split visit_end_struct() easier to reason about. While at it,
drop some assertions and comments that are not present in other
uses of the qmp output visitor, and pass NULL rather than "" as
the 'kind' parameter (matching most other uses where obj is NULL).
The changes to the generated code look like:
| qmp = qmp_event_build_dict("DEVICE_TRAY_MOVED");
|
| qov = qmp_output_visitor_new();
|- g_assert(qov);
|-
| v = qmp_output_get_visitor(qov);
|- g_assert(v);
|
|- /* Fake visit, as if all members are under a structure */
|- visit_start_struct(v, NULL, "", "DEVICE_TRAY_MOVED", 0, &err);
|+ visit_start_struct(v, NULL, NULL, "DEVICE_TRAY_MOVED", 0, &err);
| if (err) {
| goto out;
| }
| visit_type_str(v, (char **)&device, "device", &err);
| if (err) {
|- goto out;
|+ goto out_obj;
| }
| visit_type_bool(v, &tray_open, "tray-open", &err);
| if (err) {
|- goto out;
|+ goto out_obj;
| }
|- visit_end_struct(v, &err);
|+out_obj:
|+ visit_end_struct(v, err ? NULL : &err);
| if (err) {
| goto out;
| }
|
| obj = qmp_output_get_qobject(qov);
|- g_assert(obj != NULL);
|+ g_assert(obj);
|
| qdict_put_obj(qmp, "data", obj);
| emit(QAPI_EVENT_DEVICE_TRAY_MOVED, qmp, &err);
Note that the 'goto out_obj' with no intervening code before the
label, as well as the construct of 'err ? NULL : &err', are both
a bit unusual but also temporary; they get fixed in a later patch
that splits visit_end_struct() to drop its errp parameter by moving
some checking before the label. But until that time, this was the
simplest way to avoid the appearance of passing a possibly-set
error to visit_end_struct(), even though actual code inspection
shows that visit_end_struct() for a QMP output visitor will never
set an error.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-11-git-send-email-eblake@redhat.com>
[Commit message's code diff tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit 5cdc8831 reworked gen_params() to be simpler, but forgot
to clean up a now-unused errp named argument.
No change to generated code.
Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-6-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
PEP 8 calls for it, because it's forward compatible with Python 3.
Supported since Python 2.6, which we require (commit fec2103).
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1450425164-24969-2-git-send-email-armbru@redhat.com>
It should be fairly obvious that qapi base classes need to
form an acyclic graph, since QMP cannot specify the same
key more than once, while base classes are included as flat
members alongside other members added by the child. But the
old check_member_clash() parser function was not prepared to
check for this, and entered an infinite recursion (at least
until Python gives up, complaining about nesting too deep).
Now that check_member_clash() has been recently removed,
attempts at self-inheritance trigger an assertion failure
introduced by commit ac88219a. The obvious fix is to turn
the assertion into a conditional.
This patch includes both the tests (base-cycle-direct and
base-cycle-indirect) and the fix, since the .err file output
for the unfixed case is not useful (particularly when it was
warning about unbounded recursion, as that limit may be
platform-specific).
We don't need to worry about cycles in flat unions (neither
the base type nor the type of a variant can be a union) nor
in alternates (alternate branches cannot themselves be an
alternate). But if we later allow a union type as a variant,
we will still be okay, as QAPISchemaObjectTypeVariants.check()
triggers the same QAPISchemaObjectType.check() that will
detect any loops.
Likewise, we need not worry about the case of diamond
inheritance where the same class is used for a flat union base
class and one of its variants; either both uses will introduce
a collision in trying to insert the same member name twice, or
the shared type is empty and changes nothing.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
With the recent commit 'qapi: Detect collisions in C member
names', we have two different locations for detecting clashes -
one at parse time, and another at QAPISchema*.check() time.
Remove all of the ad hoc parser checks, and delete associated
code (for example, the global check_member_clash() method is
no longer needed).
Testing this showed that the test union-bad-branch wasn't adding
much: union-clash-branches also exposes the error message when
branches collide, and we've recently fixed things to avoid an
implicit collision with max. Likewise, the error for
enum-clash-member changes to report our new detection of
upper case in a value name, unless we modify the test to use
all lower case.
The wording of several error messages has changed, but the
change is generally an improvement rather than a regression.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We document that members of enums and objects should be
'lower-case', although we were not enforcing it. We have to
whitelist a few pre-existing entities that violate the norms.
Add three new tests to expose the new error message, each of
which first uses the whitelisted name 'UuidInfo' to prove the
whitelist works, then triggers the failure (this is the same
pattern used in the existing returns-whitelist.json test).
Note that by adding this check, we have effectively forbidden
an entity with a case-insensitive clash of member names, for
any entity that is not on the whitelist (although there is
still the possibility to clash via '-' vs. '_').
Not done here: a future patch should also add naming convention
support and whitelist exceptions for command, event, and type
names.
The additions to QAPISchemaMember.check_clash() check whether
info['name'] is in the whitelist (the top-most entity name at
the point 'info' tracks), rather than self.owner (the type,
possibly implicit, that directly owns the member), because it
is easier to maintain the whitelist by the names actually in
the user's .json file, rather than worrying about the names
of implicit types.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-14-git-send-email-eblake@redhat.com>
[Simplified a bit as per discussion with Eric]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than using just an array of strings, make enum.values be
an array of the new QAPISchemaMember type, and add a helper
member_names() method to get back at the original list of names.
Likewise, creating an enum requires wrapping strings, via a new
QAPISchema._make_enum_members() method. The benefit of wrapping
enum members in a QAPISchemaMember Python object is that we now
share the existing code for C name clash detection (although the
code is not yet active until a later commit removes the earlier
ad hoc parser checks).
In a related change, the QAPISchemaMember._pretty_owner() method
needs to learn about one more implicit type name: the generated
enum associated with a simple union.
In the interest of keeping the changes of this patch local to one
file, the visitor interface still passes just a list of names
rather than the full list of QAPISchemaMember instances. We may
want to revisit this in the future, if the consistency with
visit_object_type() is worth it.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-12-git-send-email-eblake@redhat.com>
[Eric's simplifying followup squashed in]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We want to share some clash detection code between enum values
and object type members. To assist with that, split off part
of QAPISchemaObjectTypeMember into a new base class
QAPISchemaMember that tracks name, owner, and common clash
detection code; while the former keeps the additional fields
for type and optional flag.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
For less code, reflect the determined boolean value of an optional
visit back to the caller instead of making the caller read the
boolean after the fact.
The resulting generated code has the following diff:
|- visit_optional(v, &has_fdset_id, "fdset-id");
|- if (has_fdset_id) {
|+ if (visit_optional(v, &has_fdset_id, "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: <1449033659-25497-10-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
Now that alternates no longer use an implicit tag, we can
inline _make_implicit_tag() into its one caller,
_def_union_type().
No change to generated code.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-7-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Previously, working with alternates required two lookup arrays
and some indirection: for type Foo, we created Foo_qtypes[]
which maps each qtype to a value of the generated FooKind enum,
then look up that value in FooKind_lookup[] like we do for other
union types.
This has a couple of subtle bugs. First, the generator was
creating a call with a parameter '(int *) &(*obj)->type' where
type is an enum type; this is unsafe if the compiler chooses
to store the enum type in a different size than int, where
assigning through the wrong size pointer can corrupt data or
cause a SIGBUS.
Related bug, not not fixed in this patch: qapi-visit.py's
gen_visit_enum() generates a cast of its enum * argument to
int *. Marked FIXME.
Second, since the values of the FooKind enum start at zero, all
entries of the Foo_qtypes[] array that were not explicitly
initialized will map to the same branch of the union as the
first member of the alternate, rather than triggering a desired
failure in visit_get_next_type(). Fortunately, the bug seldom
bites; the very next thing the input visitor does is try to
parse the incoming JSON with the wrong parser, which normally
fails; the output visitor is not used with a C struct in that
state, and the dealloc visitor has nothing to clean up (so
there is no leak).
However, the second bug IS observable in one case: parsing an
integer causes unusual behavior in an alternate that contains
at least a 'number' member but no 'int' member, because the
'number' parser accepts QTYPE_QINT in addition to the expected
QTYPE_QFLOAT (that is, since 'int' is not a member, the type
QTYPE_QINT accidentally maps to FooKind 0; if this enum value
is the 'number' branch the integer parses successfully, but if
the 'number' branch is not first, some other branch tries to
parse the integer and rejects it). A later patch will worry
about fixing alternates to always parse all inputs that a
non-alternate 'number' would accept, for now this is still
marked FIXME in the updated test-qmp-input-visitor.c, to
merely point out that new undesired behavior of 'ans' matches
the existing undesired behavior of 'asn'.
This patch fixes the default-initialization bug by deleting the
indirection, and modifying get_next_type() to directly assign a
QTypeCode parameter. This in turn fixes the type-casting bug,
as we are no longer casting a pointer to enum to a questionable
size. There is no longer a need to generate an implicit FooKind
enum associated with the alternate type (since the QMP wire
format never uses the stringized counterparts of the C union
member names). Since the updated visit_get_next_type() does not
know which qtypes are expected, the generated visitor is
modified to generate an error statement if an unexpected type is
encountered.
Callers now have to know the QTYPE_* mapping when looking at the
discriminator; but so far, only the testsuite was even using the
C struct of an alternate types. I considered the possibility of
keeping the internal enum FooKind, but initialized differently
than most generated arrays, as in:
typedef enum FooKind {
FOO_KIND_A = QTYPE_QDICT,
FOO_KIND_B = QTYPE_QINT,
} FooKind;
to create nicer aliases for knowing when to use foo->a or foo->b
when inspecting foo->type; but it turned out to add too much
complexity, especially without a client.
There is a user-visible side effect to this change, but I
consider it to be an improvement. Previously,
the invalid QMP command:
{"execute":"blockdev-add", "arguments":{"options":
{"driver":"raw", "id":"a", "file":true}}}
failed with:
{"error": {"class": "GenericError",
"desc": "Invalid parameter type for 'file', expected: QDict"}}
(visit_get_next_type() succeeded, and the error comes from the
visit_type_BlockdevOptions() expecting {}; there is no mention of
the fact that a string would also work). Now it fails with:
{"error": {"class": "GenericError",
"desc": "Invalid parameter type for 'file', expected: BlockdevRef"}}
(the error when the next type doesn't match any expected types for
the overall alternate).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
What's more meta than using qapi to define qapi? :)
Convert QType into a full-fledged[*] builtin qapi enum type, so
that a subsequent patch can then use it as the discriminator
type of qapi alternate types. Fortunately, the judicious use of
'prefix' in the qapi definition avoids churn to the spelling of
the enum constants.
To avoid circular definitions, we have to flip the order of
inclusion between "qobject.h" vs. "qapi-types.h". Back in commit
28770e0, we had the latter include the former, so that we could
use 'QObject *' for our implementation of 'any'. But that usage
also works with only a forward declaration, whereas the
definition of QObject requires QType to be a complete type.
[*] The type has to be builtin, rather than declared in
qapi/common.json, because we want to use it for alternates even
when common.json is not included. But since it is the first
builtin enum type, we have to add special cases to qapi-types
and qapi-visit to only emit definitions once, even when two
qapi files are being compiled into the same binary (the way we
already handled builtin list types like 'intList'). We may
need to revisit how multiple qapi files share common types,
but that's a project for another day.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The name QType matches our CODING_STYLE conventions for type names
in CamelCase. It also matches the fact that we are already naming
all the enum members with a prefix of QTYPE, not QTYPE_CODE. And
doing the rename will also make it easier for the next patch to use
QAPI for providing the enum, which also wants CamelCase type names.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1449033659-25497-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
When munging enum values, the fact that we were passing the entire
prefix + value through camel_to_upper() meant that enum values
spelled with CamelCase could be turned into CAMEL_CASE. However,
this provides a potential collision (both OneTwo and One-Two would
munge into ONE_TWO) for enum types, when the same two names are
valid side-by-side as QAPI member names. By changing the generation
of enum constants to always be prefix + '_' + c_name(value,
False).upper(), and ensuring that there are no case collisions (in
the next patches), we no longer have to worry about names that
would be distinct as QAPI members but collide as variant tag names,
without having to think about what munging the heuristics in
camel_to_upper() will actually perform on an enum value.
Making the change will affect enums that did not follow coding
conventions, using 'CamelCase' rather than desired 'lower-case'.
Thankfully, there are only two culprits: InputButton and ErrorClass.
We already tweaked ErrorClass to make it an alias of QapiErrorClass,
where only the alias needs changing rather than the whole tree. So
the bulk of this change is modifying INPUT_BUTTON_WHEEL_UP to the
new INPUT_BUTTON_WHEELUP (and likewise for WHEELDOWN). That part
of this commit may later need reverting if we rename the enum
constants from 'WheelUp' to 'wheel-up' as part of moving
x-input-send-event to a stable interface; but at least we have
documentation bread crumbs in place to remind us (commit 513e7cd),
and it matches the fact that SDL constants are also spelled
SDL_BUTTON_WHEELUP.
Suggested by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-27-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that we no longer collide with an implicit _MAX enum member,
we no longer need to reject it in the ad hoc parser, and can
remove several tests that are no longer needed.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-24-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes. Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.
This patch was mostly generated by applying a temporary patch:
|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
| max_index = c_enum_const(name, 'MAX', prefix)
| ret += mcgen('''
| [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
| max_index=max_index)
then running:
$ cat qapi-{types,event}.c tests/test-qapi-types.c |
sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list
The only things not generated are the changes in scripts/qapi.py.
Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We already documented that qapi names should match specific
patterns (such as starting with a letter unless it was an enum
value or a downstream extension). Tighten that from a suggestion
into a hard requirement, which frees up names beginning with a
single underscore for qapi internal usage.
The tighter regex doesn't forbid everything insane that a user
could provide (for example, a user could name a type 'Foo-lookup'
to collide with the generated 'Foo_lookup[]' for an enum 'Foo'),
but does a good job at protecting the most obvious uses, and
also happens to reserve single leading underscore for later use.
The handling of enum values starting with a digit is tricky:
commit 9fb081e introduced a subtle bug by using c_name() on
a munged value, which would allow an enum to include the
member 'q-int' in spite of our reservation. Furthermore,
munging with a leading '_' would fail our tighter regex. So
fix it by only munging for leading digits (which are never
ticklish in c_name()) and by using a different prefix (I
picked 'D', although any letter should do).
Add new tests, reserved-member-underscore and reserved-enum-q,
to demonstrate the tighter checking.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-22-git-send-email-eblake@redhat.com>
Message-Id: <1447883135-18020-1-git-send-email-eblake@redhat.com>
[Eric's fixup squashed in]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The method c_name() is supposed to do two different actions: munge
'-' into '_', and add a 'q_' prefix to ticklish names. But it did
these steps out of order, making it possible to submit input that
is not ticklish until after munging, where the output then lacked
the desired prefix.
The failure is exposed easily if you have a compiler that recognizes
C11 keywords, and try to name a member '_Thread-local', as it would
result in trying to compile the declaration 'uint64_t _Thread_local;'
which is not valid. However, this name violates our conventions
(ultimately, want to enforce that no qapi names start with single
underscore), so the test is slightly weaker by instead testing
'wchar-t'; the declaration 'uint64_t wchar_t;' is valid in C (where
wchar_t is only a typedef) but would fail with a C++ compiler (where
it is a keyword).
Fix things by reversing the order of actions within c_name().
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-18-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Detect attempts to declare two object members that would result
in the same C member name, by keying the 'seen' dictionary off
of the C name rather than the qapi name. It also requires passing
info through the check_clash() methods.
This addresses a TODO and fixes the previously-broken
args-name-clash test. The resulting error message demonstrates
the utility of the .describe() method added previously. No change
to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-17-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Future commits will migrate semantic checking away from parsing
and over to the various QAPISchema*.check() methods. But to
report an error message about an incorrect semantic use of a
member of an object type, it helps to know which type, command,
or event owns the member. In particular, when a member is
inherited from a base type, it is desirable to associate the
member name with the base type (and not the type calling
member.check()).
Rather than packing additional information into the seen array
passed to each member.check() (as in seen[m.name] = {'member':m,
'owner':type}), it is easier to have each member track the name
of the owner type in the first place (keeping things simpler
with the existing seen[m.name] = m). The new member.owner field
is set via a new set_owner() method, called when registering
the members and variants arrays with an object or variant type.
Track only a name, and not the actual type object, to avoid
creating a circular python reference chain.
Note that Variants.set_owner() method does not set the owner
for the tag_member field; this field is set earlier either as
part of an object's non-variant members, or explicitly by
alternates.
The source information is intended for human consumption in
error messages, and a new describe() method is added to access
the resulting information. For example, given the qapi:
{ 'command': 'foo', 'data': { 'string': 'str' } }
an implementation of visit_command() that calls
arg_type.members[0].describe()
will see "'string' (parameter of foo)".
To make the human-readable name of implicit types work without
duplicating efforts, the describe() method has to reverse the
name of implicit types, via the helper _pretty_owner().
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-16-git-send-email-eblake@redhat.com>
[Incorrect & unused -wrapper case in _pretty_owner() dropped]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that branches are in a separate C namespace, we can remove
the restrictions in the parser that claim a branch name would
collide with QMP, and delete the negative tests that are no
longer problematic. A separate patch can then add positive
tests to qapi-schema-test to test that any corner cases will
compile correctly.
This reverts the scripts/qapi.py portion of commit 7b2a5c2,
now that the assertions that it plugged are no longer possible.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Checking that a given QAPISchemaObjectTypeVariant.name is a
member of the corresponding QAPISchemaEnumType of the owning
QAPISchemaObjectTypeVariants.tag_member ensures that there are
no collisions in the generated C union for those tag values
(since the enum itself should have no collisions).
However, ever since its introduction in f51d8c3d, this was the
only additional action of of Variant.check(), beyond calling
the superclass Member.check(). This forces a difference in
.check() signatures, just to pass the enum type down.
Simplify things by instead doing the tag name check as part of
Variants.check(), at which point we can rely on inheritance
instead of overriding Variant.check().
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-14-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Consolidate two common sequences of clash detection into a
new QAPISchemaObjectType.check_clash() helper method.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Right now, our ad hoc parser ensures that we cannot have a
flat union that introduces any members that would clash with
non-variant members inherited from the union's base type (see
flat-union-clash-member.json). We want QAPISchemaObjectType.check()
to make the same check, so we can later reduce some of the ad
hoc checks.
We already have a map 'seen' of all non-variant members. We
still need to check for collisions between each variant type's
members and the non-variant ones.
To know the variant type's members, we need to call
variant.type.check(). This also detects when a type contains
itself in a variant, exactly like the existing base.check()
detects when a type contains itself as a base. (Except that
we currently forbid anything but a struct as the type of a
variant, so we can't actually trigger this type of loop yet.)
Slight complication: an alternate's variant can have arbitrary
type, but only an object type's check() may be called outside
QAPISchema.check(). We could either skip the call for variants
of alternates, or skip it for non-object types. For now, do
the latter, because it's easier.
Then we call each variant member's check_clash() with the
appropriate 'seen' map. Since members of different variants
can't clash, we have to clone a fresh seen for each variant.
Wrap this in a new helper method
QAPISchemaObjectTypeVariants.check_clash().
Note that cloning 'seen' inside .check_clash() resembles
the one we just removed from .check() in 'qapi: Drop
obsolete tag value collision assertions'; the difference here is
that we are now checking for clashes among the qapi members of
the variant type, rather than for a single clash with the variant
tag name itself.
Note that, by construction, collisions can't actually happen for
simple unions: each variant's type is a wrapper with a single
member 'data', which will never collide with the only non-variant
member 'type'.
For alternates, there's nothing for a variant object type's
members to clash with, and therefore no need to call the new
variants.check_clash().
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-12-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reduce the ugly flat union / simple union conditional by doing just
the essential work here, namely setting self.tag_member.
Move the rest to callers.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-7-git-send-email-armbru@redhat.com>
[rebase to earlier changes that moved tag_member.check() of
alternate types, and tweak commit title and wording]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-11-git-send-email-eblake@redhat.com>
While there, stick in a TODO change key of seen from QAPI name to C
name. Can't do it right away, because it would fail the assertion for
tests/qapi-schema/args-has-clash.json.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-6-git-send-email-armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-10-git-send-email-eblake@redhat.com>
We can use seen.values() instead if we make it an OrderedDict.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-5-git-send-email-armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-9-git-send-email-eblake@redhat.com>
This hunk
@@ -964,6 +965,7 @@ class QAPISchemaObjectType(QAPISchemaType):
members = []
seen = {}
for m in members:
+ assert c_name(m.name) not in seen
seen[m.name] = m
for m in self.local_members:
m.check(schema, members, seen)
is plainly broken.
Asserting the members inherited from base don't clash is somewhat
redundant, because self.base.check() just checked that. But it
doesn't hurt.
The idea to use c_name(m.name) instead of m.name for collision
checking is sound, because we need to catch clashes between the m.name
and between the c_name(m.name), and when two m.name clash, then their
c_name() also clash.
However, using c_name(m.name) instead of m.name in one of several
places doesn't work. See the very next line.
Keep the assertion, but drop the c_name() for now. A future commit
will bring it back.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-4-git-send-email-armbru@redhat.com>
[change TABs in commit message to space]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-8-git-send-email-eblake@redhat.com>
QAPISchemaObjectTypeVariants.check() parameter members and
QAPISchemaObjectTypeVariant.check() parameter seen are no longer used,
drop them.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-3-git-send-email-armbru@redhat.com>
[rebase to earlier changes that moved tag_member.check() of
alternate types]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-7-git-send-email-eblake@redhat.com>
QAPISchemaObjectTypeMember.check() currently does four things:
1. Compute self.type
2. Accumulate members in all_members
Only one caller cares: QAPISchemaObjectType.check() uses it to
compute self.members. The other callers pass a throw-away
accumulator.
3. Accumulate a map from names to members in seen
Only one caller cares: QAPISchemaObjectType.check() uses it to
compute its local variable seen, for self.variants.check(), which
uses it to compute self.variants.tag_member from
self.variants.tag_name. The other callers pass a throw-away
accumulator.
4. Check for collisions
This piggybacks on 3: before adding a new entry, we assert it's new.
Only one caller cares: QAPISchemaObjectType.check() uses it to
assert non-variant members don't clash.
Simplify QAPISchemaObjectType.check(): move 2.-4. to
QAPISchemaObjectType.check(), and drop parameters all_members and
seen.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-2-git-send-email-armbru@redhat.com>
[rebase to earlier changes that moved tag_member.check() of
alternate types, commit message typo fix]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-6-git-send-email-eblake@redhat.com>
Union tag values can't clash with member names in generated C anymore
since commit e4ba22b, but QAPISchemaObjectTypeVariants.check() still
asserts they don't. Drop it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1446559499-26984-1-git-send-email-armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-5-git-send-email-eblake@redhat.com>
We were previously creating all unions with an empty list for
local_members. However, it will make it easier to unify struct
and union generation if we include the generated tag member in
local_members. That way, we can have a common code pattern:
visit the base (if any), visit the local members (if any), visit
the variants (if any). The local_members of a flat union
remains empty (because the discriminator is already visited as
part of the base). Then, by visiting tag_member.check() during
AlternateType.check(), we no longer need to call it during
Variants.check().
The various front end entities now exist as follows:
struct: optional base, optional local_members, no variants
simple union: no base, one-element local_members, variants with tag_member
from local_members
flat union: base, no local_members, variants with tag_member from base
alternate: no base, no local_members, variants
With the new local members, we require a bit of finesse to
avoid assertions in the clients.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that we have separated union tag values from colliding with
non-variant C names, by naming the union 'u', we should reserve
this name for our use. Note that we want to forbid 'u' even in
a struct with no variants, because it is possible for a future
qemu release to extend QMP in a backwards-compatible manner while
converting from a struct to a flat union. Fortunately, no
existing clients were using this member name. If we ever find
the need for QMP to have a member 'u', we could at that time
relax things, perhaps by having c_name() munge the QMP member to
'q_u'.
Note that we cannot forbid 'u' everywhere (by adding the
rejection code to check_name()), because the existing QKeyCode
enum already uses it; therefore we only reserve it as a struct
type member name.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.
This patch is the front end for a series that converts to a
saner qapi union layout. By the end of the series, we will no
longer have the type/kind mismatch, and all tag values will be
under a named union, which requires clients to access
'obj->u.value' instead of 'obj->value'. But since the
conversion touches a number of files, it is easiest if we
temporarily support BOTH layouts simultaneously.
Given a simple union qapi type:
{ 'union':'Foo', 'data': { 'a':'int', 'b':'bool' } }
make the following changes in generated qapi-types.h:
| struct Foo {
|- FooKind kind;
|- union { /* union tag is @kind */
|+ union {
|+ FooKind kind;
|+ FooKind type;
|+ };
|+ union { /* union tag is @type */
| void *data;
| int64_t a;
| bool b;
|+ union { /* union tag is @type */
|+ void *data;
|+ int64_t a;
|+ bool b;
|+ } u;
| };
| };
Flat unions do not need the anonymous union for the tag member,
as we already fixed that to use the member name instead of 'kind'
back in commit 0f61af3e.
One additional change is needed in qapi.py: check_union() now
needs to check for collisions with 'type' in addition to those
with 'kind'.
Later, when the conversions are complete, we will remove the
duplication hacks, and also drop the check_union() restrictions.
Note, however, that we do not rename the generated enum, which
is still 'FooKind'. A further patch could generate implicit
enums as 'FooType', but while the generator already reserved
the '*Kind' namespace (commit 4dc2e69), there are already QMP
constructs with '*Type' naming, which means changing our
reservation namespace would have lots of churn to C code to
deal with a forced name change.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-13-git-send-email-eblake@redhat.com>
[Commit message tweaked slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
c_name() produces names starting with 'q_' when protecting a
dictionary member name that would fail to directly compile, but
in doing so can cause clashes with any member name already
beginning with 'q-' or 'q_'. Likewise, we create a C name 'has_'
for any optional member that can clash with any member name
beginning with 'has-' or 'has_'.
Technically, rather than blindly reserving the namespace,
we could try to complain about user names only when an actual
collision occurs, or even teach c_name() how to munge names
to avoid collisions. But it is not trivial, especially when
collisions can occur across multiple types (such as via
inheritance or flat unions). Besides, no existing .json
files are trying to use these names. So it's easier to just
outright forbid the potential for collision. We can always
relax things in the future if a real need arises for QMP to
express member names that have been forbidden here.
'has_' only has to be reserved for struct/union member names,
while 'q_' is reserved everywhere (matching the fact that
only members can be optional, while we use c_name() for munging
both members and entities). Note that we could relax 'q_'
restrictions on entities independently from member names; for
example, c_name('qmp_' + 'unix') would result in a different
function name than our current 'qmp_' + c_name('unix').
Update and add tests to cover the new error messages.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-6-git-send-email-eblake@redhat.com>
[Consistently pass protect=False to c_name(); commit message tweaked
slightly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Type names ending in 'List' can clash with qapi list types in
generated C. We don't currently use such names. It is easier to
outlaw them now than to worry about how to resolve such a clash
in the future. For precedence, see commit 4dc2e69, which did the
same for names ending in 'Kind' versus implicit enum types for
qapi unions.
Update the testsuite to match.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than slicing the end of a string, we can use python's
endswith(). And rather than creating a set of characters,
we can search for a character within a string.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
A future patch will move some error checking from the parser
to the various QAPISchema*.check() methods, which run only
after parsing completes. It will thus be possible to create
a python instance representing an implicit QAPI type that
parses fine but will fail validation during check(). Since
all errors have to have an associated 'info' location, we
need a location to be associated with those implicit types.
The intuitive info to use is the location of the enclosing
entity that caused the creation of the implicit type.
Note that we do not anticipate builtin types being used in
an error message (as they are not part of the user's QAPI
input, the user can't cause a semantic error in their
behavior), so we exempt those types from requiring info, by
setting a flag to track the completion of _def_predefineds(),
and tracking that flag in _def_entity().
No change to the generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-13-git-send-email-eblake@redhat.com>
[Missing QAPISchemaArrayType.is_implicit() supplied]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
For simple unions, we were creating the implicit 'type' tag
member during the QAPISchemaObjectTypeVariants constructor.
This is different from every other implicit QAPISchemaEntity
object, which get created by QAPISchema methods. Hoist the
creation to the caller (renaming _make_tag_enum() to
_make_implicit_tag()), and pass the entity rather than the
string name, so that we have the nice property that no
entities are created as a side effect within a different
entity. A later patch will then have an easier time of
associating location info with each entity creation.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-10-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Commit ac88219a had several TODO markers about whether we needed
to automatically create the corresponding array type alongside
any other type. It turns out that most of the time, we don't!
There are a few exceptions: 1) We have a few situations where we
use an array type in internal code but do not expose that type
through QMP; fix it by declaring a dummy type that forces the
generator to see that we want to use the array type.
2) The builtin arrays (such as intList for QAPI ['int']) must
always be generated, because of the way our QAPI_TYPES_BUILTIN
compile guard works: we have situations (at the very least
tests/test-qmp-output-visitor.c) that include both top-level
"qapi-types.h" (via "error.h") and a secondary
"test-qapi-types.h". If we were to only emit the builtin types
when used locally, then the first .h file would not include all
types, but the second .h does not declare anything at all because
the first .h set QAPI_TYPES_BUILTIN, and we would end up with
compilation error due to things like unknown type 'int8List'.
Actually, we may need to revisit how we do type guards, and
change from a single QAPI_TYPES_BUILTIN over to a different
usage pattern that does one #ifdef per qapi type - right now,
the only types that are declared multiple times between two qapi
.json files for inclusion by a single .c file happen to be the
builtin arrays. But now that we have QAPI 'include' statements,
it is logical to assume that we will soon reach a point where
we want to reuse non-builtin types (yes, I'm thinking about what
it will take to add introspection to QGA, where we will want to
reuse the SchemaInfo type and friends). One #ifdef per type
will help ensure that generating the same qapi type into more
than one qapi-types.h won't cause collisions when both are
included in the same .c file; but we also have to solve how to
avoid creating duplicate qapi-types.c entry points. So that
is a problem left for another day.
Generated code for qapi-types and qapi-visit is drastically
reduced; less than a third of the arrays that were blindly
created were actually needed (a quick grep shows we dropped
from 219 to 69 *List types), and the .o files lost more than
30% of their bulk. [For best results, diff the generated
files with 'git diff --patience --no-index pre post'.]
Interestingly, the introspection output is unchanged - this is
because we already cull all types that are not indirectly
reachable from a command or event, so introspection was already
using only a subset of array types. The subset of types
introspected is now a much larger percentage of the overall set
of array types emitted in qapi-types.h (since the larger set
shrunk), but still not 100% (evidence that the array types
emitted for our new Dummy structs, and the new struct itself,
don't affect QMP).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-9-git-send-email-eblake@redhat.com>
[Moved array info tracking to a later patch]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
A future patch will enable error reporting from the various
QAPISchema*.check() methods. But to report an error related
to an implicit type, we'll need to associate a location with
the type (the same location as the top-level entity that is
causing the creation of the implicit type), and once we do
that, keying off of whether foo.info exists is no longer a
viable way to determine if foo is an implicit type.
Instead, add an is_implicit() method to QAPISchemaEntity, and use it.
It can be overridden later for ObjectType and EnumType, when implicit
instances of those classes gain info.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-8-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
qapi-schema-test was already testing that we could have a
command returning int, but burned a command name in the whitelist.
Merge the redundant positive test returns-int, and pick a name
that reduces the whitelist size.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-6-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next few patches will start migrating error checking from
ad hoc parse methods into the QAPISchema*.check() methods. But
for an error message to display, we first have to fix the
overall 'try' to catch those errors. We also want to enable a
few more assertions, such as making sure every attempt to
raise a semantic error is passed a valid location info, or that
various preconditions hold.
The general approach for moving error checking will then be to
relax an assertion into an if that raises an exception if the
condition does not hold, and removing the counterpart ad hoc
check done during the parse phase.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Previously, qapi-types and qapi-visit filtered out implicit
objects during visit_object_type() by using 'info' (works since
implicit objects do not [yet] have associated info); meanwhile
qapi-introspect filtered out all schema types on the first pass
by returning a python type from visit_begin(), which was then
used at a distance in QAPISchema.visit() to do the filtering.
Rather than keeping these ad hoc approaches, add a new visitor
callback visit_needed() which returns False to skip a given
entity, and which defaults to True unless overridden. Use the
new mechanism to simplify all three filtering visitors.
No change to the generated code.
Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1444710158-8723-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Since we have consolidated all generated code to use 'err' as
the name of the local variable for error detection, we can
simplify the decision on whether to skip error detection (useful
for deallocation paths) to be a boolean.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-18-git-send-email-eblake@redhat.com>
[Change to gen_visit_fields() simplified]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Consolidate the code between visit, command marshalling, and
event generation that iterates over the members of a struct.
It reduces code duplication in the generator, so that a future
patch can reduce the size of generated code while touching only
one instead of three locations.
There are no changes to the generated marshal code.
The visitor code becomes slightly more verbose, but remains
semantically equivalent, and is actually easier to read as
it follows a more common idiom:
| visit_optional(v, &(*obj)->has_device, "device", &err);
|- if (!err && (*obj)->has_device) {
|- visit_type_str(v, &(*obj)->device, "device", &err);
|- }
| if (err) {
| goto out;
| }
|+ if ((*obj)->has_device) {
|+ visit_type_str(v, &(*obj)->device, "device", &err);
|+ if (err) {
|+ goto out;
|+ }
|+ }
The event code becomes slightly more verbose, but this is
arguably a bug fix: although the visitors are not well
documented, use of an optional member should not be attempted
unless guarded by a prior call to visit_optional(). Works only
because the output qmp visitor has a no-op visit_optional():
|+ visit_optional(v, &has_offset, "offset", &err);
|+ if (err) {
|+ goto out;
|+ }
| if (has_offset) {
| visit_type_int(v, &offset, "offset", &err);
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-17-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
qapi-commands has a nice helper gen_err_check(), but did not
use it everywhere. In fact, using it in more places makes it
easier to reduce the lines of code used for generating error
checks. This in turn will make it easier for later patches
to consolidate another common pattern among the generators.
The generated code has fewer blank lines in qapi-event.c functions,
but has no semantic difference.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-16-git-send-email-eblake@redhat.com>
[Drop another blank line for symmetry]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than open-code the check for a valid base type, we
should reuse the common functionality. This allows for
consistent error messages, and also makes it easier for a
later patch to turn on support for inline anonymous base
structures.
Test flat-union-inline is updated to test only one feature
(anonymous branch dictionaries), which can be implemented
independently (test flat-union-bad-base already covers the
idea of an anonymous base dictionary).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-10-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The previous commit added two tests that triggered an assertion
failure. It's fairly straightforward to avoid the failure by
just outright forbidding the collision between a union's tag
values and its discriminator name (including the implicit name
'kind' supplied for simple unions [*]). Ultimately, we'd like
to move the collision detection into QAPISchema*.check(), but
for now it is easier just to enhance the existing checks.
[*] Of course, down the road, we have plans to rename the simple
union tag name to 'type' to match the QMP wire name, but the
idea of the collision will still be present even then.
Technically, we could avoid the collision by naming the C union
members representing each enum value as '_case_value' rather
than 'value'; but until we have an actual qapi client (and not
just our testsuite) that has a legitimate reason to match a
case label to the name of a QMP key and needs the name munging
to satisfy the compiler, it's easier to just reject the qapi
as invalid.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-7-git-send-email-eblake@redhat.com>
[Polished a few comments]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Silence pep8, and make pylint a bit happier. Just style cleanups,
plus killing a useless comment in camel_to_upper(); no semantic
changes.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
pylint recommends that every exception class should explicitly
invoke the superclass __init__, even though things seem to work
fine without it.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Use of '"...%s" % include' to print non-strings can lead to
ugly messages, such as this (if the .json change is applied
without the qapi.py change):
Expected a file name (string), got: OrderedDict()
Better is to just omit the actual non-string value in the
message.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
qapi/introspect.json defines the introspection schema. It's designed
for QMP introspection, but should do for similar uses, such as QGA.
The introspection schema does not reflect all the rules and
restrictions that apply to QAPI schemata. A valid QAPI schema has an
introspection value conforming to the introspection schema, but the
converse is not true.
Introspection lowers away a number of schema details, and makes
implicit things explicit:
* The built-in types are declared with their JSON type.
All integer types are mapped to 'int', because how many bits we use
internally is an implementation detail. It could be pressed into
external interface service as very approximate range information,
but that's a bad idea. If we need range information, we better do
it properly.
* Implicit type definitions are made explicit, and given
auto-generated names:
- Array types, named by appending "List" to the name of their
element type, like in generated C.
- The enumeration types implicitly defined by simple union types,
named by appending "Kind" to the name of their simple union type,
like in generated C.
- Types that don't occur in generated C. Their names start with ':'
so they don't clash with the user's names.
* All type references are by name.
* The struct and union types are generalized into an object type.
* Base types are flattened.
* Commands take a single argument and return a single result.
Dictionary argument or list result is an implicit type definition.
The empty object type is used when a command takes no arguments or
produces no results.
The argument is always of object type, but the introspection schema
doesn't reflect that.
The 'gen': false directive is omitted as implementation detail.
The 'success-response' directive is omitted as well for now, even
though it's not an implementation detail, because it's not used by
QMP.
* Events carry a single data value.
Implicit type definition and empty object type use, just like for
commands.
The value is of object type, but the introspection schema doesn't
reflect that.
* Types not used by commands or events are omitted.
Indirect use counts as use.
* Optional members have a default, which can only be null right now
Instead of a mandatory "optional" flag, we have an optional default.
No default means mandatory, default null means optional without
default value. Non-null is available for optional with default
(possible future extension).
* Clients should *not* look up types by name, because type names are
not ABI. Look up the command or event you're interested in, then
follow the references.
TODO Should we hide the type names to eliminate the temptation?
New generator scripts/qapi-introspect.py computes an introspection
value for its input, and generates a C variable holding it.
It can generate awfully long lines. Marked TODO.
A new test-qmp-input-visitor test case feeds its result for both
tests/qapi-schema/qapi-schema-test.json and qapi-schema.json to a
QmpInputVisitor to verify it actually conforms to the schema.
New QMP command query-qmp-schema takes its return value from that
variable. Its reply is some 85KiBytes for me right now.
If this turns out to be too much, we have a couple of options:
* We can use shorter names in the JSON. Not the QMP style.
* Optionally return the sub-schema for commands and events given as
arguments.
Right now qmp_query_schema() sends the string literal computed by
qmp-introspect.py. To compute sub-schema at run time, we'd have to
duplicate parts of qapi-introspect.py in C. Unattractive.
* Let clients cache the output of query-qmp-schema.
It changes only on QEMU upgrades, i.e. rarely. Provide a command
query-qmp-schema-hash. Clients can have a cache indexed by hash,
and re-query the schema only when they don't have it cached. Even
simpler: put the hash in the QMP greeting.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
'gen': false needs to stay for now, because netdev_add is still using
it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-25-git-send-email-armbru@redhat.com>
With the previous commit, the generated marshalers just work, and save
us a bit of handwritten code.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-23-git-send-email-armbru@redhat.com>
It's first class, because unlike '**', it actually works, i.e. doesn't
require 'gen': false.
'**' will go away next.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Generated qapi-event.[ch] lose line breaks. No change otherwise.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-18-git-send-email-armbru@redhat.com>
Generate just 'FOO' instead of 'struct FOO' when possible.
Drop helper functions that are now unused.
Make pep8 and pylint reasonably happy.
Rename generate_FOO() functions to gen_FOO() for consistency.
Use more consistent and sensible variable names.
Consistently use c_ for mapping keys when their value is a C
identifier or type.
Simplify gen_enum() and gen_visit_union()
Consistently use single quotes for C text string literals.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-14-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
is_c_ptr() looks whether the end of the C text for the type looks like
a pointer. Works, but is fragile.
We now have a better tool: use QAPISchemaType method c_null(). The
initializers for non-pointers become prettier: 0, false or the
enumeration constant with the value 0 instead of {0}.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-13-git-send-email-armbru@redhat.com>
Duplicated in commit 21cd70d. Yes, we can't import qapi-types, but
that's no excuse. Move the helpers from qapi-types.py to qapi.py, and
replace the duplicates in qapi-event.py.
The generated event enumeration type's lookup table becomes
const-correct (see commit 2e4450f), and uses explicit indexes instead
of relying on order (see commit 912ae9c).
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-10-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Output unchanged apart from reordering and white-space.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1442401589-24189-9-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Fixes flat unions to get the base's base members. Test case is from
commit 2fc0043, in qapi-schema-test.json:
{ 'union': 'UserDefFlatUnion',
'base': 'UserDefUnionBase',
'discriminator': 'enum1',
'data': { 'value1' : 'UserDefA',
'value2' : 'UserDefB',
'value3' : 'UserDefB' } }
{ 'struct': 'UserDefUnionBase',
'base': 'UserDefZero',
'data': { 'string': 'str', 'enum1': 'EnumOne' } }
{ 'struct': 'UserDefZero',
'data': { 'integer': 'int' } }
Patch's effect on UserDefFlatUnion:
struct UserDefFlatUnion {
/* Members inherited from UserDefUnionBase: */
+ int64_t integer;
char *string;
EnumOne enum1;
/* Own members: */
union { /* union tag is @enum1 */
void *data;
UserDefA *value1;
UserDefB *value2;
UserDefB *value3;
};
};
Flat union visitors remain broken. They'll be fixed next.
Code is generated in a different order now, but that doesn't matter.
The two guards QAPI_TYPES_BUILTIN_STRUCT_DECL and
QAPI_TYPES_BUILTIN_CLEANUP_DECL are replaced by just
QAPI_TYPES_BUILTIN.
Two ugly special cases for simple unions now stand out like sore
thumbs:
1. The type tag is named 'type' everywhere, except in generated C,
where it's 'kind'.
2. QAPISchema lowers simple unions to semantically equivalent flat
unions. However, the C generated for a simple unions differs from
the C generated for its equivalent flat union, and we therefore
need special code to preserve that pointless difference for now.
Mark both TODO.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The visitor will help keeping the code generation code simple and
reasonably separated from QAPISchema details.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-5-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
New methods c_name(), c_type(), c_null(), json_type(),
alternate_qtype().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1442401589-24189-4-git-send-email-armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The QAPI code generators work with a syntax tree (nested dictionaries)
plus a few symbol tables (also dictionaries) on the side.
They have clearly outgrown these simple data structures. There's lots
of rummaging around in dictionaries, and information is recomputed on
the fly. For the work I'm going to do, I want more clearly defined
and more convenient interfaces.
Going forward, I also want less coupling between the back-ends and the
syntax tree, to make messing with the syntax easier.
Create a bunch of classes to represent QAPI schemata.
Have the QAPISchema initializer call the parser, then walk the syntax
tree to create the new internal representation, and finally perform
semantic analysis.
Shortcut: the semantic analysis still relies on existing check_exprs()
to do the actual semantic checking. All this code needs to move into
the classes. Mark as TODO.
Simple unions are lowered to flat unions. Flat unions and structs are
represented as a more general object type.
Catching name collisions in generated code would be nice. Mark as
TODO.
We generate array types eagerly, even though most of them aren't used.
Mark as TODO.
Nothing uses the new intermediate representation just yet, thus no
change to generated files.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
I want to name a new class QAPISchema.
While there, make it a new-style class.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-2-git-send-email-armbru@redhat.com>
The camel_to_upper() method applies some heuristics to turn
a mixed case type name into an all-uppercase name. This is
used for example, to generate enum constant name prefixes.
The heuristics don't also generate a satisfactory name
though. eg
{ 'enum': 'QCryptoTLSCredsEndpoint',
'data': ['client', 'server']}
Results in Q_CRYPTOTLS_CREDS_ENDPOINT_CLIENT. This has
an undesirable _ after the initial Q and is missing an
_ between the CRYPTO & TLS strings.
Rather than try to add more and more heuristics to try
to cope with this, simply allow the QAPI schema to
specify the desired enum constant prefix explicitly.
eg
{ 'enum': 'QCryptoTLSCredsEndpoint',
'prefix': 'QCRYPTO_TLS_CREDS_ENDPOINT',
'data': ['client', 'server']}
Now gives the QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT name.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A feature new in Python 2.7 crept into commit 77e703b: re.subn()'s
fifth argument. Avoid that, use re.compile().
Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 1441640755-23902-1-git-send-email-armbru@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
check_type() first checks and peels off the array type, then checks
the element type. For two out of four error messages, it takes pains
to report errors for "array of T" instead of just T. Odd. Let's
examine the errors.
* Unknown element type, e.g.
tests/qapi-schema/args-array-unknown.json:
Member 'array' of 'data' for command 'oops' uses unknown type
'array of NoSuchType'
To make sense of this, you need to know that 'array of NoSuchType'
refers to '[NoSuchType]'. Easy enough. However, simply reporting
Member 'array' of 'data' for command 'oops' uses unknown type
'NoSuchType'
is at least as easy to understand.
* Element type's meta-type is inadmissible, e.g.
tests/qapi-schema/returns-whitelist.json:
'returns' for command 'no-way-this-will-get-whitelisted' cannot
use built-in type 'array of int'
'array of int' is technically not a built-in type, but that's
pedantry. However, simply reporting
'returns' for command 'no-way-this-will-get-whitelisted' cannot
use built-in type 'int'
avoids the issue, and is at least as easy to understand.
* The remaining two errors are unreachable, because the array checking
ensures that value is a string.
Thus, reporting some errors for "array of T" instead of just T works,
but doesn't really improve things. Drop it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The first check ensures the second one can't trigger. Drop the first
one, because the second one is in a more logical place, and emits a
nicer error message.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reproducer: with
{ 'command': 'user_def_cmd4', 'returns': { 'a': 'int' } }
added to qapi-schema-test.json, qapi-commands.py dies when it tries to
generate the command handler function
Traceback (most recent call last):
File "/work/armbru/qemu/scripts/qapi-commands.py", line 359, in <module>
ret = generate_command_decl(cmd['command'], arglist, ret_type) + "\n"
File "/work/armbru/qemu/scripts/qapi-commands.py", line 29, in generate_command_decl
ret_type=c_type(ret_type), name=c_name(name),
File "/work/armbru/qemu/scripts/qapi.py", line 927, in c_type
assert isinstance(value, str) and value != ""
AssertionError
because the return type doesn't exist.
Simply outlaw this usage, and drop or dumb down test cases accordingly.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
A command's or event's 'data' must be a struct type, given either as a
dictionary, or as struct type name.
Commit dd883c6 tightened the checking there, but not enough: we still
accept 'union'. Fix to reject it.
We may want to support union types there, but we'll have to extend
qapi-commands.py and qapi-events.py for it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
We don't actually enforce our "other than downstream extensions [...],
all names should begin with a letter" rule. Add a FIXME.
We should reject names that differ only in '_' vs. '.' vs. '-',
because they're liable to clash in generated C. Add a FIXME.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
gen_sync_call()'s parameter indent is useless: gen_sync_call() uses it
only as optional argument for push_indent() and pop_indent(), their
default is four, and gen_sync_call()'s only caller passes four. Drop
the parameter.
gen_visitor_input_containers_decl()'s parameter obj is always
"QOBJECT(args)". Use that, and drop the parameter.
Drop unused parameters of gen_marshal_output(),
gen_marshal_input_decl(), generate_visit_struct_body(),
generate_visit_list(), generate_visit_enum(), generate_declaration(),
generate_enum_declaration(), generate_decl_enum().
Drop unused variables in generate_event_enum_lookup(),
generate_enum_lookup(), generate_visit_struct_fields(), check_event().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
qapi-event.py breaks when you ask for a funny prefix like '@'.
Protect it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The guards around built-in declarations lose their _H. It never made
much sense anyway.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Commit 05dfb26 added eatspace stripping to mcgen(). Move it to
cgen(), just in case somebody gets tempted to use cgen() directly
instead of via mcgen().
cgen() indents blank lines. No such lines get generated right now,
but fix it anyway.
We use triple-quoted strings for program text, like this:
'''
Program text
any number of lines
'''
Keeps the program text relatively readable, but puts an extra newline
at either end. mcgen() "fixes" that by dropping the first and last
line outright. Drop only the newlines.
This unmasks a bug in qapi-commands.py: four quotes instead of three.
Fix it up.
Output doesn't change
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Insert comments to separate sections dealing with parsing, semantic
analysis, code generation, and so forth.
Move helpers to their proper section.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Eric Blake