As mentioned in previous patches, we want to call visit_end_struct()
functions unconditionally, so that visitors can release resources
tied up since the matching visit_start_struct() without also having
to worry about error priority if more than one error occurs.
Even though error_propagate() can be safely used to ignore a second
error during cleanup caused by a first error, it is simpler if the
cleanup cannot set an error. So, split out the error checking
portion (basically, input visitors checking for unvisited keys) into
a new function visit_check_struct(), which can be safely skipped if
any earlier errors are encountered, and leave the cleanup portion
(which never fails, but must be called unconditionally if
visit_start_struct() succeeded) in visit_end_struct().
Generated code in qapi-visit.c has diffs resembling:
|@@ -59,10 +59,12 @@ void visit_type_ACPIOSTInfo(Visitor *v,
| goto out_obj;
| }
| visit_type_ACPIOSTInfo_members(v, obj, &err);
|- error_propagate(errp, err);
|- err = NULL;
|+ if (err) {
|+ goto out_obj;
|+ }
|+ visit_check_struct(v, &err);
| out_obj:
|- visit_end_struct(v, &err);
|+ visit_end_struct(v);
| out:
and in qapi-event.c:
@@ -47,7 +47,10 @@ void qapi_event_send_acpi_device_ost(ACP
| goto out;
| }
| visit_type_q_obj_ACPI_DEVICE_OST_arg_members(v, ¶m, &err);
|- visit_end_struct(v, err ? NULL : &err);
|+ if (!err) {
|+ visit_check_struct(v, &err);
|+ }
|+ visit_end_struct(v);
| if (err) {
| goto out;
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-20-git-send-email-eblake@redhat.com>
[Conflict with a doc fixup resolved]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than generate inline per-member visits, take advantage
of the 'visit_type_FOO_members()' function for emitting events.
This is possible now that implicit structs can be visited like
any other. Generated code shrinks accordingly; by initializing
a struct based on parameters, through a new gen_param_var()
helper, like:
|@@ -338,6 +250,9 @@ void qapi_event_send_block_job_error(con
| QMPEventFuncEmit emit = qmp_event_get_func_emit();
| QmpOutputVisitor *qov;
| Visitor *v;
|+ q_obj_BLOCK_JOB_ERROR_arg param = {
|+ (char *)device, operation, action
|+ };
|
| if (!emit) {
| return;
@@ -351,19 +266,7 @@ void qapi_event_send_block_job_error(con
| if (err) {
| goto out;
| }
|- visit_type_str(v, "device", (char **)&device, &err);
|- if (err) {
|- goto out_obj;
|- }
|- visit_type_IoOperationType(v, "operation", &operation, &err);
|- if (err) {
|- goto out_obj;
|- }
|- visit_type_BlockErrorAction(v, "action", &action, &err);
|- if (err) {
|- goto out_obj;
|- }
|-out_obj:
|+ visit_type_q_obj_BLOCK_JOB_ERROR_arg_members(v, ¶m, &err);
| visit_end_struct(v, err ? NULL : &err);
Notice that the initialization of 'param' has to cast away const
(just as the old gen_visit_members() had to do): we can't change
the signature of the user function (which uses 'const char *'), but
have to assign it to a non-const QAPI object (which requires
'char *').
While touching this, document with a FIXME comment that there is
still a potential collision between QMP members and our choice of
local variable names within qapi_event_send_FOO().
This patch also paves the way for some followup simplifications
in the generator, in subsequent patches.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-8-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We are getting closer to the point where we could use one union
as the base or variant type within another union type (as long
as there are no collisions between any possible combination of
member names allowed across all discriminator choices). But
until we get to that point, it is worth asserting that variants
are not present in places where we are not prepared to handle
them: when exploding a type into a parameter list, we do not
expect variants. The qapi.py code is already checking this,
via the older check_type() method; but someday we hope to get
rid of that and move checking into QAPISchema*.check(). The
two asserts added here make sure any refactoring still catches
problems, and makes it locally obvious why we can iterate over
only type.members without worrying about type.variants.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-2-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>
As a followup to commit cbf2115, clean up the includes in files
generated by QAPI so that osdep.h is included first in .c files,
and headers which it implies are not included manually. This
patch is done manually, since Coccinelle (and therefore
scripts/clean-includes) doesn't see into the generator scripts.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
visit_start_struct() and visit_type_enum() had a 'kind' argument
that was usually set to either the stringized version of the
corresponding qapi type name, or to NULL (although some clients
didn't even get that right). But nothing ever used the argument.
It's even hard to argue that it would be useful in a debugger,
as a stack backtrace also tells which type is being visited.
Therefore, drop the 'kind' argument as dead.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-22-git-send-email-eblake@redhat.com>
[Harmless rebase mistake cleaned up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
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>
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.
This patch names the goto labels 'out' (not 'clean') and 'out_obj'
(not 'out_end'). Additionally, the generator was inconsistent on
whether labels had a leading space [our HACKING is silent; while
emacs 'gnu' style adds the space to avoid littering column 1].
For minimal churn, prefer no leading space; this also matches
the style that is more prevalent in current qemu.git.
No change in semantics to the generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-13-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.
This patch consistently names the local error variable 'err' rather
than 'local_err'.
No change in semantics to the generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@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>
Fixes events whose data is struct with base to include the struct's
base members. Test case is qapi-schema-test.json's event
__org.qemu_x-command:
{ 'event': '__ORG.QEMU_X-EVENT', 'data': '__org.qemu_x-Struct' }
{ 'struct': '__org.qemu_x-Struct', 'base': '__org.qemu_x-Base',
'data': { '__org.qemu_x-member2': 'str' } }
{ 'struct': '__org.qemu_x-Base',
'data': { '__org.qemu_x-member1': '__org.qemu_x-Enum' } }
Patch's effect on generated qapi_event_send___org_qemu_x_event():
-void qapi_event_send___org_qemu_x_event(const char *__org_qemu_x_member2,
+void qapi_event_send___org_qemu_x_event(__org_qemu_x_Enum __org_qemu_x_member1,
+ const char *__org_qemu_x_member2,
Error **errp)
{
QDict *qmp;
@@ -224,6 +225,10 @@ void qapi_event_send___org_qemu_x_event(
goto clean;
}
+ visit_type___org_qemu_x_Enum(v, &__org_qemu_x_member1, "__org.qemu_x-member1", &local_err);
+ if (local_err) {
+ goto clean;
+ }
visit_type_str(v, (char **)&__org_qemu_x_member2, "__org.qemu_x-member2", &local_err);
if (local_err) {
goto clean;
Code is generated in a different order now, but that doesn't matter.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
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: <1442401589-24189-11-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>
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>
Clean up white-space, brace placement, and superfluous #ifdef
QAPI_TYPES_BUILTIN_CLEANUP_DEF.
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>
Use c_name() instead of ad hoc code. Doesn't upcase the -p prefix,
which is an improvement in my book. Unbreaks prefix containing '.',
but other funny characters remain broken. To be fixed next.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Now that the two functions are identical, we only need one of them,
and we might as well give it a more descriptive name. Basically,
the function serves as the translation from a QAPI name into a
(portion of a) C identifier, without regards to whether it is a
variable or function name.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
A future patch will be using a 'name':{dictionary} entry in the
QAPI schema to specify a default value for an optional argument
(see previous commit messages for more details why); but existing
use of inline nested structs conflicts with that goal. Now that
all commands have been changed to avoid inline nested structs,
nuke support for them, and turn it into a hard error. Update the
testsuite to reflect tighter parsing rules.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
qapi-event.py will parse the schema and generate qapi-event.c, then
the API in qapi-event.c can be used to handle events in qemu code.
All API have prefix "qapi_event".
The script mainly includes two parts: generate API for each event
define, generate an enum type for all defined events.
Since in some cases the real emit behavior may change, for example,
qemu-img would not send a event, a callback layer is used to
control the behavior. As a result, the stubs at compile time
can be saved, the binding of block layer code and monitor code
will become looser.
Signed-off-by: Wenchao Xia <wenchaoqemu@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Eric Blake