qemu-e2k/tests/qapi-schema/event-boxed-empty.json

# 'boxed' requires a non-empty type

##
# @FOO:
##
{ 'event': 'FOO', 'boxed': true }
qapi: Implement boxed types for commands/events 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> 2016-07-14 05:50:20 +02:00			`# 'boxed' requires a non-empty type`
qapi: add qapi2texi script 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> 2017-01-13 15:41:29 +01:00
			`##`
			`# @FOO:`
			`##`
qapi: Implement boxed types for commands/events 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> 2016-07-14 05:50:20 +02:00			`{ 'event': 'FOO', 'boxed': true }`