Turn on the ability to pass command and event arguments in
a single boxed parameter, which must name a non-empty type
(although the type can be a struct with all optional members).
For structs, it makes it possible to pass a single qapi type
instead of a breakout of all struct members (useful if the
arguments are already in a struct or if the number of members
is large); for other complex types, it is now possible to use
a union or alternate as the data for a command or event.
The empty type may be technically feasible if needed down the
road, but it's easier to forbid it now and relax things to allow
it later, than it is to allow it now and have to special case
how the generated 'q_empty' type is handled (see commit 7ce106a9
for reasons why nothing is generated for the empty type). An
alternate type is never considered empty, but now that a boxed
type can be either an object or an alternate, we have to provide
a trivial QAPISchemaAlternateType.is_empty(). The new call to
arg_type.is_empty() during QAPISchemaCommand.check() requires
that we first check the type in question; but there is no chance
of introducing a cycle since objects do not refer back to commands.
We still have a split in syntax checking between ad-hoc parsing
up front (merely validates that 'boxed' has a sane value) and
during .check() methods (if 'boxed' is set, then 'data' must name
a non-empty user-defined type).
Generated code is unchanged, as long as no client uses the
new feature.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-10-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Test files renamed to *-boxed-*]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The next patch will add support for passing a qapi union type
as the 'data' of a command. But to do that, the user function
for implementing the command, as called by the generated
marshal command, must take the corresponding C struct as a
single boxed pointer, rather than a breakdown into one
parameter per member. Even without a union, being able to use
a C struct rather than a list of parameters can make it much
easier to handle coding with QAPI.
This patch adds the internal plumbing of a 'boxed' flag
associated with each command and event. In several cases,
this means adding indentation, with one new dead branch and
the remaining branch being the original code more deeply
nested; this was done so that the new implementation in the
next patch is easier to review without also being mixed with
indentation changes.
For this patch, no behavior or generated output changes, other
than the testsuite outputting the value of the new flag
(always False for now).
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-9-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[Identifier box renamed to boxed in two places]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Ever since commit 12f254f removed the last parameterization
of gen_err_check(), it no longer makes sense to hide the three
lines of generated C code behind a macro call. Just inline it
into the remaining users.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-7-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
In the near future, we want to lift our artificial restriction of
no variants at the top level of an event, at which point the
currently open-coded check for empty members will become
insufficient. Factor it out into a new helper method is_empty()
now, and future-proof it by checking variants, too, along with an
assert that it is not used prior to the completion of .check().
Update places that were checking for (non-)empty .members to use
the new helper.
All of the current callers assert that there are no variants (either
directly, or by qapi.py asserting that base types have no variants),
so this is not a semantic change.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-6-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Making each output visitor provide its own output collection
function was the only remaining reason for exposing visitor
sub-types to the rest of the code base. Add a polymorphic
visit_complete() function which is a no-op for input visitors,
and which populates an opaque pointer for output visitors. For
maximum type-safety, also add a parameter to the output visitor
constructors with a type-correct version of the output pointer,
and assert that the two uses match.
This approach was considered superior to either passing the
output parameter only during construction (action at a distance
during visit_free() feels awkward) or only during visit_complete()
(defeating type safety makes it easier to use incorrectly).
Most callers were function-local, and therefore a mechanical
conversion; the testsuite was a bit trickier, but the previous
cleanup patch minimized the churn here.
The visit_complete() function may be called at most once; doing
so lets us use transfer semantics rather than duplication or
ref-count semantics to get the just-built output back to the
caller, even though it means our behavior is not idempotent.
Generated code is simplified as follows for events:
|@@ -26,7 +26,7 @@ void qapi_event_send_acpi_device_ost(ACP
| QDict *qmp;
| Error *err = NULL;
| QMPEventFuncEmit emit;
|- QmpOutputVisitor *qov;
|+ QObject *obj;
| Visitor *v;
| q_obj_ACPI_DEVICE_OST_arg param = {
| info
|@@ -39,8 +39,7 @@ void qapi_event_send_acpi_device_ost(ACP
|
| qmp = qmp_event_build_dict("ACPI_DEVICE_OST");
|
|- qov = qmp_output_visitor_new();
|- v = qmp_output_get_visitor(qov);
|+ v = qmp_output_visitor_new(&obj);
|
| visit_start_struct(v, "ACPI_DEVICE_OST", NULL, 0, &err);
| if (err) {
|@@ -55,7 +54,8 @@ void qapi_event_send_acpi_device_ost(ACP
| goto out;
| }
|
|- qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov));
|+ visit_complete(v, &obj);
|+ qdict_put_obj(qmp, "data", obj);
| emit(QAPI_EVENT_ACPI_DEVICE_OST, qmp, &err);
and for commands:
| {
| Error *err = NULL;
|- QmpOutputVisitor *qov = qmp_output_visitor_new();
| Visitor *v;
|
|- v = qmp_output_get_visitor(qov);
|+ v = qmp_output_visitor_new(ret_out);
| visit_type_AddfdInfo(v, "unused", &ret_in, &err);
|- if (err) {
|- goto out;
|+ if (!err) {
|+ visit_complete(v, ret_out);
| }
|- *ret_out = qmp_output_get_qobject(qov);
|-
|-out:
| error_propagate(errp, err);
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-13-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Now that we have a polymorphic visit_free(), we no longer need
qmp_input_visitor_cleanup(); which in turn means we no longer
need to return a subtype from qmp_input_visitor_new() nor a
public upcast function.
Generated code changes to qmp-marshal.c look like:
|@@ -52,11 +52,10 @@ void qmp_marshal_add_fd(QDict *args, QOb
| {
| Error *err = NULL;
| AddfdInfo *retval;
|- QmpInputVisitor *qiv = qmp_input_visitor_new(QOBJECT(args), true);
| Visitor *v;
| q_obj_add_fd_arg arg = {0};
|
|- v = qmp_input_get_visitor(qiv);
|+ v = qmp_input_visitor_new(QOBJECT(args), true);
| visit_start_struct(v, NULL, NULL, 0, &err);
| if (err) {
| goto out;
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-8-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Making each visitor provide its own (awkwardly-named) FOO_cleanup()
is unusual, when we can instead have a polymorphic visit_free()
interface. Over the next few patches, we can use the polymorphic
functions to eliminate the need for a FOO_get_visitor() function
for accessing specific visitor functionality, once everything can
be accessed directly through the Visitor* interfaces.
The dealloc visitor is the first one converted to completely use
the new entry point, since qapi_dealloc_visitor_cleanup() was the
only reason that qapi_dealloc_get_visitor() existed, and only
generated and testsuite code was even using it. With the new
visit_free() entry point in place, we no longer need to expose
the QapiDeallocVisitor subtype through qapi_dealloc_visitor_new(),
and can get by with less generated code, with diffs that look like:
| void qapi_free_ACPIOSTInfo(ACPIOSTInfo *obj)
| {
|- QapiDeallocVisitor *qdv;
| Visitor *v;
|
| if (!obj) {
| return;
| }
|
|- qdv = qapi_dealloc_visitor_new();
|- v = qapi_dealloc_get_visitor(qdv);
|+ v = qapi_dealloc_visitor_new();
| visit_type_ACPIOSTInfo(v, NULL, &obj, NULL);
|- qapi_dealloc_visitor_cleanup(qdv);
|+ visit_free(v);
|}
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-5-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than making the dealloc visitor track of stack of pointers
remembered during visit_start_* in order to free them during
visit_end_*, it's a lot easier to just make all callers pass the
same pointer to visit_end_*. The generated code has access to the
same pointer, while all other users are doing virtual walks and
can pass NULL. The dealloc visitor is then greatly simplified.
All three visit_end_*() functions intentionally take a void**,
even though the visit_start_*() functions differ between void**,
GenericList**, and GenericAlternate**. This is done for several
reasons: when doing a virtual walk, passing NULL doesn't care
what the type is, but when doing a generated walk, we already
have to cast the caller's specific FOO* to call visit_start,
while using void** lets us use visit_end without a cast. Also,
an upcoming patch will add a clone visitor that wants to use
the same implementation for all three visit_end callbacks,
which is made easier if all three share the same signature.
For visitors with already track per-object state (the QMP visitors
via a stack, and the string visitors which do not allow nesting),
add an assertion that the caller is indeed passing the same
pointer to paired calls.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-4-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
The qmp-input visitor was allowing callers to play rather fast
and loose: when visiting a QDict, you could grab members of the
root dictionary without first pushing into the dict; among the
culprit callers was the generated marshal code on the 'arguments'
dictionary of a QMP command. But we are about to tighten the
input visitor, at which point the generated marshal code MUST
follow the same paradigms as everyone else, of pushing into the
struct before grabbing its keys.
Generated code grows as follows:
|@@ -515,7 +641,12 @@ void qmp_marshal_blockdev_backup(QDict *
| BlockdevBackup arg = {0};
|
| v = qmp_input_get_visitor(qiv);
|+ visit_start_struct(v, NULL, NULL, 0, &err);
|+ if (err) {
|+ goto out;
|+ }
| visit_type_BlockdevBackup_members(v, &arg, &err);
|+ visit_end_struct(v, err ? NULL : &err);
| if (err) {
| goto out;
| }
|@@ -527,7 +715,9 @@ out:
| qmp_input_visitor_cleanup(qiv);
| qdv = qapi_dealloc_visitor_new();
| v = qapi_dealloc_get_visitor(qdv);
|+ visit_start_struct(v, NULL, NULL, 0, NULL);
| visit_type_BlockdevBackup_members(v, &arg, NULL);
|+ visit_end_struct(v, NULL);
| qapi_dealloc_visitor_cleanup(qdv);
| }
The use of 'err ? NULL : &err' is temporary; a later patch will
clean that up when it splits visit_end_struct().
Prior to this patch, the fact that there was no final
visit_end_struct() meant that even though we are using a strict
input visit, the marshalling code was not detecting excess input
at the top level (only in nested levels). Fortunately, we have
code in monitor.c:qmp_check_client_args() that also checks for
no excess arguments at the top level. But as the generated code
is more compact than the manual check, a later patch will clean
up monitor.c to drop the redundancy added here.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-9-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Rather than having two separate ways to create a QMP input
visitor, where the safer approach has the more verbose name,
it is better to consolidate things into a single function
where the caller must explicitly choose whether to be strict
or to ignore excess input. This patch is the strictly
mechanical conversion; the next patch will then audit which
uses can be made stricter.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-6-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Originally, gen_marshal_input_visit() (or gen_visitor_input_block()
before commit f1538019) was factored out to make it easy to do two
passes of a visit to each member of a (possibly-implicit) object,
without duplicating lots of code. But after recent changes, those
visits now occupy a single line of emitted code, and the helper
method has become a series of conditionals both before and after
the one important line, making it rather awkward to see at a glance
what gets emitted on the first (parsing) or second (deallocation)
pass. It's a lot easier to read the generator code if we just
inline both uses directly into gen_marshal(), without all the
conditionals.
Once we've done that, it's easy to notice that gen_marshal_vars()
is used only once, and inlining it too lets us consolidate some
mcgen() calls that used to be split across helpers.
gen_call() remains a single-use helper function, but it has
enough indentation and complexity that inlining it would hamper
legibility.
No change to generated output. The fact that the diffstat shows
a net reduction in lines is an argument in favor of this cleanup.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-10-git-send-email-eblake@redhat.com>
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 command
marshalling. This is possible now that implicit structs can be
visited like any other. Generate call arguments from a stack-
allocated struct, rather than a list of local variables:
|@@ -57,26 +57,15 @@ void qmp_marshal_add_fd(QDict *args, QOb
| QmpInputVisitor *qiv = qmp_input_visitor_new_strict(QOBJECT(args));
| QapiDeallocVisitor *qdv;
| Visitor *v;
|- bool has_fdset_id = false;
|- int64_t fdset_id = 0;
|- bool has_opaque = false;
|- char *opaque = NULL;
|+ q_obj_add_fd_arg arg = {0};
|
| v = qmp_input_get_visitor(qiv);
|- if (visit_optional(v, "fdset-id", &has_fdset_id)) {
|- visit_type_int(v, "fdset-id", &fdset_id, &err);
|- if (err) {
|- goto out;
|- }
|- }
|- if (visit_optional(v, "opaque", &has_opaque)) {
|- visit_type_str(v, "opaque", &opaque, &err);
|- if (err) {
|- goto out;
|- }
|+ visit_type_q_obj_add_fd_arg_members(v, &arg, &err);
|+ if (err) {
|+ goto out;
| }
|
|- retval = qmp_add_fd(has_fdset_id, fdset_id, has_opaque, opaque, &err);
|+ retval = qmp_add_fd(arg.has_fdset_id, arg.fdset_id, arg.has_opaque, arg.opaque, &err);
| if (err) {
| goto out;
| }
|@@ -88,12 +77,7 @@ out:
| qmp_input_visitor_cleanup(qiv);
| qdv = qapi_dealloc_visitor_new();
| v = qapi_dealloc_get_visitor(qdv);
|- if (visit_optional(v, "fdset-id", &has_fdset_id)) {
|- visit_type_int(v, "fdset-id", &fdset_id, NULL);
|- }
|- if (visit_optional(v, "opaque", &has_opaque)) {
|- visit_type_str(v, "opaque", &opaque, NULL);
|- }
|+ visit_type_q_obj_add_fd_arg_members(v, &arg, NULL);
| qapi_dealloc_visitor_cleanup(qdv);
| }
This also has the nice side effect of eliminating a chance of
collision between argument QMP names and local variables.
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: <1458254921-17042-9-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The generator special-cased
{ 'command':'foo', 'data': {} }
to avoid emitting a visitor variable, but failed to see that
{ 'struct':'NamedEmptyType, 'data': {} }
{ 'command':'foo', 'data':'NamedEmptyType' }
needs the same treatment. There, the generator happily generates a
visitor to get no arguments, and a visitor to destroy no arguments;
and the compiler isn't happy with that, as demonstrated by the updated
qapi-schema-test.json:
tests/test-qmp-marshal.c: In function ‘qmp_marshal_user_def_cmd0’:
tests/test-qmp-marshal.c:264:14: error: variable ‘v’ set but not used [-Werror=unused-but-set-variable]
Visitor *v;
^
No change to generated code except for the testsuite addition.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-3-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>
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>
We were using regular expressions to see if ret included
any earlier text that emitted a 'goto out;' line, to decide
whether we needed to output an 'out:' label. But this is
fragile, if the ret text can possibly combine more than one
generated function body, where the first function used a
goto but the second does not. Change the code to just check
for the known conditions which cause an error check to be
needed. Besides, it's slightly more efficient to use plain
checks than regular expression searching.
No change to generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1445898903-12082-4-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>
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 reduces the number of push_indent()/pop_indent() pairs
so that generated code is typically already at its natural output
indentation in the python files. It is easier to reason about
generated code if the reader does not have to track how much
spacing will be inserted alongside the code, and moreso when all
of the generators use the same patterns (qapi-type and qapi-event
were already using in-place indentation).
Arguably, the resulting python may be a bit harder to read with C
code at the same indentation as python; on the other hand, not
having to think about push_indent() is a win, and most decent
editors provide syntax highlighting that makes it easier to
visually distinguish python code from string literals that will
become C code.
There is no change to the generated output.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-15-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 names the local visitor variable 'v' rather than 'm'.
Related objects, such as 'QapiDeallocVisitor', are also named by
their initials instead of an unrelated leading m.
No change in semantics to the generated code.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1443565276-4535-12-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>
gen_marshal_output() uses its parameter name only for name of the
generated function. Name it after the type being marshaled instead of
its caller, and drop duplicates.
Saves 7 copies of qmp_marshal_output_int() in qemu-ga, and one copy of
qmp_marshal_output_str() in qemu-system-*.
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: <1442401589-24189-19-git-send-email-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>
These functions marshal both input and output.
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: <1442401589-24189-17-git-send-email-armbru@redhat.com>
Rename gen_marshal_input() to gen_marshal(), because the generated
function marshals both arguments and results.
Rename gen_visitor_input_containers_decl() to gen_marshal_vars(), and
move the other variable declarations there, too.
Rename gen_visitor_input_block() to gen_marshal_input_visit(), and
rearrange its code slightly.
Rename gen_marshal_input_decl() to gen_marshal_proto(), because the
result isn't a full declaration, unlike gen_command_decl()'s.
New gen_marshal_decl() actually returns a full declaration.
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: <1442401589-24189-16-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>
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>
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>
In generated command handlers, the assignment to retval dominates its
only use. Therefore, its initialization is useless. Drop it.
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Multiple passes through mcgen() is prone to produce unwanted blank
lines, which we then combat by sprinkling .rstrip() on top. Just
don't do it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
gen_err_check() hard-codes 'local_err' instead of substituting the
argument. Currently harmless, since all callers pass either None or
'local_err'.
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>
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>
In particular, don't include it into headers.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
The traditional QMP command handler interface
int qmp_FOO(Monitor *mon, const QDict *params, QObject **ret_data);
doesn't provide for returning an Error object. Instead, the handler
is expected to stash it in the monitor with qerror_report().
When we rebased QMP on top of QAPI, we didn't change this interface.
Instead, commit 776574d introduced "middle mode" as a temporary aid
for converting existing QMP commands to QAPI one by one. More than
three years later, we're still using it.
Middle mode has two effects:
* Instead of the native input marshallers
static void qmp_marshal_input_FOO(QDict *, QObject **, Error **)
it generates input marshallers conforming to the traditional QMP
command handler interface.
* It suppresses generation of code to register them with
qmp_register_command()
This permits giving them internal linkage.
As long as we need qmp-commands.hx, we can't use the registry behind
qmp_register_command(), so the latter has to stay for now.
The former has to go to get rid of qerror_report(). Changing all QMP
commands to fit the QAPI mold in one go was impractical back when we
started, but by now there are just a few stragglers left:
do_qmp_capabilities(), qmp_qom_set(), qmp_qom_get(), qmp_object_add(),
qmp_netdev_add(), do_device_add().
Switch middle mode to generate native input marshallers, and adapt the
stragglers. Simplifies both the monitor code and the stragglers.
Rename do_qmp_capabilities() to qmp_capabilities(), and
do_device_add() to qmp_device_add, because that's how QMP command
handlers are named today.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
Anything but --type sync (which is the default) suppresses output
entirely, which makes no sense.
Dates back to the initial commit c17d990. Commit message says
"Currently only generators for synchronous qapi/qmp functions are
supported", so maybe output other than "synchronous qapi/qmp" was
planned at the time, to be selected with --type.
Should other kinds of output ever materialize, we can put the option
back.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Enhance the testsuite to cover downstream events and commands.
Events worked without more tweaks, but commands needed a few final
updates in the generator to mangle names in the appropriate places.
In making those tweaks, it was easier to drop type_visitor() and
inline its actions instead.
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@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>
For a few QMP commands, we are forced to pass an arbitrary type
without tracking it properly in QAPI. Among the existing clients,
this unnamed type was spelled 'dict', 'visitor', and '**'; this
patch standardizes on '**', matching the documentation changes
earlier in the series.
Meanwhile, for the 'gen' key, we have been ignoring the value,
although the schema consistently used "'no'" ('success-response'
was hard-coded to checking for 'no'). But now that we can support
a literal "false" in the schema, we might as well use that rather
than ignoring the value or special-casing a random string. Note
that these are one-way switches (use of 'gen':true is not the same
as omitting 'gen'). Also, the use of '**' requires 'gen':false,
but the use of 'gen':false does not mandate the use of '**'.
There is no difference to the generated code. Add some tests on
what we'd like to guarantee, although it will take later patches
to clean up test results and actually enforce the use of a bool
parameter.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
