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* qapi: The #optional tag is redundant, dropMarkus Armbruster2017-03-161-7/+5Star
| | | | | | | | | | | | | | | | | | | | | | | | | We traditionally mark optional members #optional in the doc comment. Before commit 3313b61, this was entirely manual. Commit 3313b61 added some automation because its qapi2texi.py relied on #optional to determine whether a member is optional. This is no longer the case since the previous commit: the only thing qapi2texi.py still does with #optional is stripping it out. We still reject bogus qapi-schema.json and six places for qga/qapi-schema.json. Thus, you can't actually rely on #optional to see whether something is optional. Yet we still make people add it manually. That's just busy-work. Drop the code to check, fix up and strip out #optional, along with all instances of #optional. To keep it out, add code to reject it, to be dropped again once the dust settles. No change to generated documentation. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <1489582656-31133-18-git-send-email-armbru@redhat.com>
* qapi: Have each QAPI schema declare its name rule violationsMarkus Armbruster2017-03-161-0/+6
| | | | | | | | | | | qapi.py has a hardcoded white-list of type names that may violate the rule on use of upper and lower case. Add a new pragma directive 'name-case-whitelist', and use it to replace the hard-coded white-list. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1489582656-31133-7-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* qapi: Have each QAPI schema declare its returns white-listMarkus Armbruster2017-03-161-6/+7
| | | | | | | | | | qapi.py has a hardcoded white-list of command names that may violate the rules on permitted return types. Add a new pragma directive 'returns-whitelist', and use it to replace the hard-coded white-list. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1489582656-31133-6-git-send-email-armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
* docs/qapi-code-gen.txt: Drop confusing reference to 'gen'Markus Armbruster2017-03-161-10/+8Star
| | | | | | | | | | | Section "Commands" qualifies its rules on permitted argument and return types "with one exception noted below when 'gen' is used". The note went away in commit 2d21291. Clean up the dangling references. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <1489582656-31133-5-git-send-email-armbru@redhat.com>
* qapi: Make doc comments optional where we don't need themMarkus Armbruster2017-03-161-13/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | Since we added the documentation generator in commit 3313b61, doc comments are mandatory. That's a very good idea for a schema that needs to be documented, but has proven to be annoying for testing. Make doc comments optional again, but add a new directive { 'pragma': { 'doc-required': true } } to let a QAPI schema require them. Add test cases for the new pragma directive. While there, plug a minor hole in includ directive test coverage. Require documentation in the schemas we actually want documented: qapi-schema.json and qga/qapi-schema.json. We could probably make qapi2texi.py cope with incomplete documentation, but for now, simply make it refuse to run unless the schema has 'doc-required': true. Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1489582656-31133-3-git-send-email-armbru@redhat.com> [qapi-code-gen.txt wording tweaked] Reviewed-by: Eric Blake <eblake@redhat.com>
* docs/qapi-code-gen.txt: Clarify naming rulesMarkus Armbruster2017-03-071-22/+39
| | | | | | Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Message-Id: <1488317230-26248-24-git-send-email-armbru@redhat.com>
* qapi: Drop unused non-strict qobject input visitorMarkus Armbruster2017-03-051-1/+1
| | | | | | | | | | The split between tests/test-qobject-input-visitor.c and tests/test-qobject-input-strict.c now makes less sense than ever. The next commit will take care of that. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <1488544368-30622-20-git-send-email-armbru@redhat.com>
* qapi: add qapi2texi scriptMarc-André Lureau2017-01-161-33/+147
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As the name suggests, the qapi2texi script converts JSON QAPI description into a texi file suitable for different target formats (info/man/txt/pdf/html...). It parses the following kind of blocks: Free-form: ## # = Section # == Subsection # # Some text foo with *emphasis* # 1. with a list # 2. like that # # And some code: # | $ echo foo # | -> do this # | <- get that # ## Symbol description: ## # @symbol: # # Symbol body ditto ergo sum. Foo bar # baz ding. # # @param1: the frob to frobnicate # @param2: #optional how hard to frobnicate # # Returns: the frobnicated frob. # If frob isn't frobnicatable, GenericError. # # Since: version # Notes: notes, comments can have # - itemized list # - like this # # Example: # # -> { "execute": "quit" } # <- { "return": {} } # ## That's roughly following the following EBNF grammar: api_comment = "##\n" comment "##\n" comment = freeform_comment | symbol_comment freeform_comment = { "# " text "\n" | "#\n" } symbol_comment = "# @" name ":\n" { member | tag_section | freeform_comment } member = "# @" name ':' [ text ] "\n" freeform_comment tag_section = "# " ( "Returns:", "Since:", "Note:", "Notes:", "Example:", "Examples:" ) [ text ] "\n" freeform_comment text = free text with markup Note that the grammar is ambiguous: a line "# @foo:\n" can be parsed both as freeform_comment and as symbol_comment. The actual parser recognizes symbol_comment. See docs/qapi-code-gen.txt for more details. Deficiencies and limitations: - the generated QMP documentation includes internal types - union type support is lacking - type information is lacking in generated documentation - doc comment error message positions are imprecise, they point to the beginning of the comment. - a few minor issues, all marked TODO/FIXME in the code Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20170113144135.5150-16-marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [test-qapi.py tweaked to avoid trailing empty lines in .out] Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: rename QmpOutputVisitor to QObjectOutputVisitorDaniel P. Berrange2016-10-251-1/+1
| | | | | | | | | | | | | | | | | | The QmpOutputVisitor has no direct dependency on QMP. It is valid to use it anywhere that one wants a QObject. Rename it to better reflect its functionality as a generic QAPI to QObject converter. The commit before previous renamed the files, this one renames C identifiers. Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1475246744-29302-6-git-send-email-berrange@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Split into file rename and identifier rename] Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: rename QmpInputVisitor to QObjectInputVisitorDaniel P. Berrange2016-10-251-1/+1
| | | | | | | | | | | | | | | | | The QmpInputVisitor has no direct dependency on QMP. It is valid to use it anywhere that one has a QObject. Rename it to better reflect its functionality as a generic QObject to QAPI converter. The previous commit renamed the files, this one renames C identifiers. Reviewed-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> Message-Id: <1475246744-29302-5-git-send-email-berrange@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> [Straightforwardly rebased, split into file and identifier rename] Signed-off-by: Markus Armbruster <armbru@redhat.com>
* Replace qmp-commands.hx by docs/qmp-commands.txtMarc-André Lureau2016-09-191-3/+3
| | | | | | | | | | | | | The only remaining function of qmp-commands.hx is to let us generate qmp-commands.txt from it. Replace qmp-commands.hx by qmp-commands.txt. We intend to move the documentation into the QAPI schema and generate qapi-commands.txt from it, but not right now. Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> Message-Id: <20160912091913.15831-19-marcandre.lureau@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Implement boxed types for commands/eventsEric Blake2016-07-191-2/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Add new visit_complete() functionEric Blake2016-07-061-7/+3Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qmp-input-visitor: Favor new visit_free() functionEric Blake2016-07-061-2/+1Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Add new visit_free() functionEric Blake2016-07-061-18/+10Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Add parameter to visit_end_*Eric Blake2016-07-061-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* docs: "specify" spell fixMichael Tokarev2016-06-071-1/+1
| | | | | Signed-off-by: Michael Tokarev <mjt@tls.msk.ru> Reviewed-by: Eric Blake <eblake@redhat.com>
* qapi: Change visit_type_FOO() to no longer return partial objectsEric Blake2016-05-121-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Returning a partial object on error is an invitation for a careless caller to leak memory. We already fixed things in an earlier patch to guarantee NULL if visit_start fails ("qapi: Guarantee NULL obj on input visitor callback error"), but that does not help the case where visit_start succeeds but some other failure happens before visit_end, such that we leak a partially constructed object outside visit_type_FOO(). As no one outside the testsuite was actually relying on these semantics, it is cleaner to just document and guarantee that ALL pointer-based visit_type_FOO() functions always leave a safe value in *obj during an input visitor (either the new object on success, or NULL if an error is encountered), so callers can now unconditionally use qapi_free_FOO() to clean up regardless of whether an error occurred. The decision is done by adding visit_is_input(), then updating the generated code to check if additional cleanup is needed based on the type of visitor in use. Note that we still leave *obj unchanged after a scalar-based visit_type_FOO(); I did not feel like auditing all uses of visit_type_Enum() to see if the callers would tolerate a specific sentinel value (not to mention having to decide whether it would be better to use 0 or ENUM__MAX as that sentinel). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1461879932-9020-25-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Simplify semantics of visit_next_list()Eric Blake2016-05-121-7/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The semantics of the list visit are somewhat baroque, with the following pseudocode when FooList is used: start() for (prev = head; cur = next(prev); prev = &cur) { visit(&cur->value) } Note that these semantics (advance before visit) requires that the first call to next() return the list head, while all other calls return the next element of the list; that is, every visitor implementation is required to track extra state to decide whether to return the input as-is, or to advance. It also requires an argument of 'GenericList **' to next(), solely because the first iteration might need to modify the caller's GenericList head, so that all other calls have to do a layer of dereferencing. Thankfully, we only have two uses of list visits in the entire code base: one in spapr_drc (which completely avoids visit_next_list(), feeding in integers from a different source than uint8List), and one in qapi-visit.py. That is, all other list visitors are generated in qapi-visit.c, and share the same paradigm based on a qapi FooList type, so we can refactor how lists are laid out with minimal churn among clients. We can greatly simplify things by hoisting the special case into the start() routine, and flipping the order in the loop to visit before advance: start(head) for (tail = *head; tail; tail = next(tail)) { visit(&tail->value) } With the simpler semantics, visitors have less state to track, the argument to next() is reduced to 'GenericList *', and it also becomes obvious whether an input visitor is allocating a FooList during visit_start_list() (rather than the old way of not knowing if an allocation happened until the first visit_next_list()). As a minor drawback, we now allocate in two functions instead of one, and have to pass the size to both functions (unless we were to tweak the input visitors to cache the size to start_list for reuse during next_list, but that defeats the goal of less visitor state). The signature of visit_start_list() is chosen to match visit_start_struct(), with the new parameters after 'name'. The spapr_drc case is a virtual visit, done by passing NULL for list, similarly to how NULL is passed to visit_start_struct() when a qapi type is not used in those visits. It was easy to provide these semantics for qmp-output and dealloc visitors, and a bit harder for qmp-input (several prerequisite patches refactored things to make this patch straightforward). But it turned out that the string and opts visitors munge enough other state during visit_next_list() to make it easier to just document and require a GenericList visit for now; an assertion will remind us to adjust things if we need the semantics in the future. Several pre-requisite cleanup patches made the reshuffling of the various visitors easier; particularly the qmp input visitor. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1461879932-9020-24-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Split visit_end_struct() into piecesEric Blake2016-05-121-5/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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, &param, &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>
* qapi-commands: Wrap argument visit in visit_start_structEric Blake2016-05-121-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Consolidate QMP input visitor creationEric Blake2016-05-121-1/+1
| | | | | | | | | | | | | | 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>
* qapi: Allow anonymous base for flat unionEric Blake2016-03-181-13/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Make BlockdevOptions doc example closer to realityEric Blake2016-03-181-37/+37
| | | | | | | | | | | | | | | | | | | | | Although we don't want to repeat the entire BlockdevOptions QMP command in the example, it helps if we aren't needlessly diverging (the initial example was written before we had committed the actual QMP interface). Use names that match what is found in qapi/block-core.json, such as '*read-only' rather than 'readonly', or 'BlockdevRef' rather than 'BlockRef'. For the simple union example, invent BlockdevOptionsSimple so that later text is unambiguous which of the two union forms is meant (telling the user to refer back to two 'BlockdevOptions' wasn't nice, and QMP has only the flat union form). Also, mention that the discriminator of a flat union is non-optional. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1458254921-17042-14-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Adjust names of implicit typesEric Blake2016-03-181-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Update docs to match recent generator changesEric Blake2016-03-051-162/+178
| | | | | | | | | | | | | | | | | | | | | | | | | | Several commits have been changing the generator, but not updating the docs to match: - The implicit tag member is named "type", not "kind". Screwed up in commit 39a1815. - Commit 9f08c8ec made list types lazy, and thereby dropped UserDefOneList if nothing explicitly uses the list type. - Commit 51e72bc1 switched the parameter order with 'name' occurring earlier. - Commit e65d89bf changed the layout of UserDefOneList. - Prefer the term 'member' over 'field'. - We now expose visit_type_FOO_members() for objects. - etc. Rework the examples to show slightly more output (we don't want to show too much; that's what the testsuite is for), and regenerate the output to match all recent changes. Also, rearrange output to show .h files before .c (understanding the interface first often makes the implementation easier to follow). Reported-by: Marc-André Lureau <marcandre.lureau@redhat.com> Signed-off-by: Eric Blake <eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <1457021813-10704-5-git-send-email-eblake@redhat.com>
* qapi: Forbid empty unions and useless alternatesEric Blake2016-02-191-7/+8
| | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Simplify visiting of alternate typesEric Blake2015-12-171-3/+0Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Convert QType into QAPI built-in enum typeEric Blake2015-12-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Don't let implicit enum MAX member collideEric Blake2015-12-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Tighten the regex on valid namesEric Blake2015-12-171-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Document introspection stability considerationsEric Blake2015-11-171-0/+11
| | | | | | | | | | | | | | | We are not ready (and might never be ready) to declare introspection stable between releases. Clients written to control multiple versions of qemu, and desiring to know whether a particular member is supported for a given command, must be prepared to locate that member in spite of qapi changes that may affect the member's location or type within the overall object, even though such changes did not break QMP wire back-compatibility. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1447264202-19554-1-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi-introspect: Document lack of sortingEric Blake2015-11-101-4/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | qapi-code-gen.txt already claims that types, commands, and events share a common namespace; set this in stone by further documenting that our introspection output will never have collisions with the same name tied to more than one meta-type. Our largest QMP enum currently has 125 values, our largest object type has 27 members, and the mean for each is less than 10. These sizes are small enough that the per-element overhead of O(log n) binary searching probably outweighs the speed possible with direct O(n) linear searching (a better algorithm with more overhead will only beat a leaner naive algorithm only as you scale to larger input sizes). Arguably, the overall SchemaInfo array could be sorted by name; there, we currently have 531 entities, large enough for a binary search to be faster than linear. However, remember that we have mutually-recursive types, which means there is no topological ordering that will allow clients to learn all information about that type in a single linear pass; thus clients will want to do random access over the data, and they will probably read the introspection output into a hashtable for O(1) lookup rather than O(log n) binary searching, at which point, pre-sorting our introspection output doesn't help the client. It doesn't help that sorting can be subjective if you introduce locales into the mix (I'm not experienced enough with Python to know for sure, but at least it looks like it defaults to sorting in the C locale even when run under a different locale). And while our current introspection output is deterministic (because we visit entities in a sorted order), we may want to change that order in the future (such as using OrderedDict to stick to .json declaration order). For these reasons, we simply document that clients should not rely on any particular order of items in introspection output. And since it is now a documented part of the contract, we have the freedom to later rearrange output if needed, without worrying about breaking well-written clients. Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1446791754-23823-13-git-send-email-eblake@redhat.com> [Commit message tweaked] Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Provide nicer array names in introspectionEric Blake2015-11-101-2/+5
| | | | | | | | | | | | | | | | | | For the sake of humans reading introspection output, it is nice to have the name of implicit array types be recognizable as arrays of the underlying type. However, while this patch allows humans to skip from a command with return type "[123]" straight to the definition of type "123" without having to first inspect type "[123]", document that this shortcut should not be taken by client apps. This makes the resulting introspection string slightly larger by default (just over 200 bytes), but it's in the noise (less than 0.3% of the overall 70k size of 'query-qmp-capabilities'). Signed-off-by: Eric Blake <eblake@redhat.com> Message-Id: <1446791754-23823-12-git-send-email-eblake@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com>
* qapi: Reserve 'q_*' and 'has_*' member namesEric Blake2015-11-021-4/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Reserve '*List' type names for list typesEric Blake2015-11-021-1/+2
| | | | | | | | | | | | | | | 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>
* qapi: Consistent generated code: prefer visitor 'v'Eric Blake2015-10-121-37/+37
| | | | | | | | | | | | | | | | | 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>
* qapi: Consistent generated code: prefer error 'err'Eric Blake2015-10-121-14/+14
| | | | | | | | | | | | | | | | 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>
* qapi-introspect: Hide type namesMarkus Armbruster2015-09-211-19/+17Star
| | | | | | | | | | | | | To eliminate the temptation for clients to look up types by name (which are not ABI), replace all type names by meaningless strings. Reduces output of query-schema by 13 out of 85KiB. As a debugging aid, provide option -u to suppress the hiding. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-Id: <1442401589-24189-27-git-send-email-armbru@redhat.com>
* qapi: New QMP command query-qmp-schema for QMP introspectionMarkus Armbruster2015-09-211-5/+232
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: Pseudo-type '**' is now unused, drop itMarkus Armbruster2015-09-211-12/+6Star
| | | | | | | | | | '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>
* qapi-schema: Fix up misleading specification of netdev_addMarkus Armbruster2015-09-211-1/+1
| | | | | | | | | | | | | | | | | It doesn't take a 'props' argument, let alone one in the format "NAME=VALUE,..." The bogus arguments specification doesn't matter due to 'gen': false. Clean it up to be incomplete rather than wrong, and document the incompleteness. While there, improve netdev_add usage example in the manual: add a device option to show how it's done. 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: <1442401589-24189-24-git-send-email-armbru@redhat.com>
* qapi: Introduce a first class 'any' typeMarkus Armbruster2015-09-211-0/+1
| | | | | | | | | | | 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>
* qapi: Improve built-in type documentationMarkus Armbruster2015-09-211-11/+18
| | | | | | | | | | Clarify how they map to JSON. Add how they map to C. Fix the reference to StringInputVisitor. 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: <1442401589-24189-20-git-send-email-armbru@redhat.com>
* qapi-commands: De-duplicate output marshaling functionsMarkus Armbruster2015-09-211-2/+2
| | | | | | | | | | | | | | 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>
* qapi: Rename qmp_marshal_input_FOO() to qmp_marshal_FOO()Markus Armbruster2015-09-211-2/+2
| | | | | | | | | 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>
* qapi: Clean up after recent conversions to QAPISchemaVisitorMarkus Armbruster2015-09-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: De-duplicate enum code generationMarkus Armbruster2015-09-211-4/+5
| | | | | | | | | | | | | | | 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>
* qapi-types: Convert to QAPISchemaVisitor, fixing flat unionsMarkus Armbruster2015-09-211-15/+14Star
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* qapi: allow override of default enum prefix namingDaniel P. Berrange2015-09-151-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>