The include directive permits modular QAPI schemata, but the generated
code is monolithic all the same. To permit generating modular code,
the front end needs to pass more information on inclusions to the back
ends. The commit before last added the necessary information to the
parse tree. This commit adds it to the intermediate representation
and its QAPISchemaVisitor. A later commit will use this to to
generate modular code.
New entity QAPISchemaInclude represents inclusions. Call new visitor
method visit_include() for it, so visitors can see the sub-modules a
module includes.
Note that unlike other entities, QAPISchemaInclude has no name, and is
therefore not added to entity_dict.
New QAPISchemaEntity attribute @module names the entity's source file.
Call new visitor method visit_module() when it changes during a visit,
so visitors can keep track of the module being visited.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180211093607.27351-18-armbru@redhat.com>
[eblake: avoid accidental deletion of self._predefining]
Signed-off-by: Eric Blake <eblake@redhat.com>
The generators' conversion to visitors (merge commit 9e72681d16)
changed the processing order of entities from source order to
alphabetical order. The next commit needs source order, so change it
back.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180211093607.27351-17-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Error messages print absolute file names of included files even if the
user gave a relative one on the command line:
$ PYTHONPATH=scripts python -B tests/qapi-schema/test-qapi.py tests/qapi-schema/include-cycle.json
In file included from tests/qapi-schema/include-cycle.json:1:
In file included from /work/armbru/qemu/tests/qapi-schema/include-cycle-b.json:1:
/work/armbru/qemu/tests/qapi-schema/include-cycle-c.json:1: Inclusion loop for include-cycle.json
Improve this to
In file included from tests/qapi-schema/include-cycle.json:1:
In file included from tests/qapi-schema/include-cycle-b.json:1:
tests/qapi-schema/include-cycle-c.json:1: Inclusion loop for include-cycle.json
The error message when an include file can't be opened prints the
include directive's file name, which is relative to the including
file. Change this to print the file name relative to the working
directory. Visible in tests/qapi-schema/include-no-file.err.
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: <20180211093607.27351-12-armbru@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Whenever qapi-schema.json changes, we run six programs eleven times to
update eleven files. Similar for qga/qapi-schema.json. This is
silly. Replace the six programs by a single program that spits out
all eleven files.
The programs become modules in new Python package qapi, along with the
helper library. This requires moving them to scripts/qapi/. While
moving them, consistently drop executable mode bits.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180211093607.27351-9-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
[eblake: move change to one-line 'blurb' earlier in series, mention mode
bit change as intentional, update qapi-code-gen.txt to match actual
generated events.c file]
Signed-off-by: Eric Blake <eblake@redhat.com>
Every generator has separate boilerplate for .h and .c, and their
differences are boring. All of them repeat the license note.
Reduce the repetition as follows. Move common text like the license
note to common open_output(), next to the existing common text there.
For each generator, replace the two separate descriptions by a single
one.
While there, emit an "automatically generated" note into generated
documentation, too.
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: <20180211093607.27351-3-armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The iteritems()/itervalues() methods are gone in py3, but the
items()/values() methods are still around. The latter are less
efficient than the former in py2, but this has unmeasurably
small impact on QEMU build time, so taking portability over
efficiency is a net win.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20180116134217.8725-3-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Python 3 no longer supports the bare "print" statement, it must be
called as a normal function with round brackets. It is possible to
opt-in to this new syntax with Python 2.6 onwards by importing the
"print_function" from the "__future__" module, making it easy to
support Python 2 and 3 in parallel.
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <20180116134217.8725-2-berrange@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Use a string instead of a list of strings. While there, generate
fewer superfluous blank lines.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20171002141341.24616-10-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Use a string instead of a list of strings.
This makes qapi2texi.py generate additional blank lines. They're
harmless, and the next commit will get rid of them again.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20171002141341.24616-9-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
We have two representations of sections without a name: the main
section uses name=None, the others name=''. Standardize on name=None.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20171002141341.24616-8-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
A negative test case crept into doc-good.json: invalid use of section
markup we currently fail to reject. Move this into its own
doc-bad-section.json.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20171002141341.24616-6-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The conflict check added by commit c0644771 ("qapi: Reject
alternates that can't work with keyval_parse()") doesn't work
with the following declaration:
{ 'alternate': 'Alt',
'data': { 'one': 'bool',
'two': 'str' } }
It crashes with:
Traceback (most recent call last):
File "./scripts/qapi-types.py", line 295, in <module>
schema = QAPISchema(input_file)
File "/home/ehabkost/rh/proj/virt/qemu/scripts/qapi.py", line 1468, in __init__
self.exprs = check_exprs(parser.exprs)
File "/home/ehabkost/rh/proj/virt/qemu/scripts/qapi.py", line 958, in check_exprs
check_alternate(expr, info)
File "/home/ehabkost/rh/proj/virt/qemu/scripts/qapi.py", line 830, in check_alternate
% (name, key, types_seen[qtype]))
KeyError: 'QTYPE_QSTRING'
This happens because the previously-seen conflicting member
('one') can't be found at types_seen[qtype], but at
types_seen['QTYPE_BOOL'].
Fix the bug by moving the error check to the same loop that adds
new items to types_seen, raising an exception if types_seen[qt]
is already set.
Add two additional test cases that can detect the bug.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20170717180926.14924-1-ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
I expect the 'null' type to be useful mostly for members of alternate
types.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We would like to use a same QObject type to represent numbers, whether
they are int, uint, or floats. Getters will allow some compatibility
between the various types if the number fits other representations.
Add a few more tests while at it.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170607163635.17635-7-marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[parse_stats_intervals() simplified a bit, comment in
test_visitor_in_int_overflow() tidied up, suppress bogus warnings]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Alternates with both a 'number' and an 'int' branch will become
invalid when the next patch merges of QFloat and QInt into QNum.
More sophisticated alternate code could keep them valid, but since
we have no users outside tests, simply drop the tests.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20170607163635.17635-4-marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Alternates are sum types like unions, but use the JSON type on the
wire / QType in QObject instead of an explicit tag. That's why we
require alternate members to have distinct QTypes.
The recently introduced keyval_parse() (commit d454dbe) can only
produce string scalars. The qobject_input_visitor_new_keyval() input
visitor mostly hides the difference, so code using a QObject input
visitor doesn't have to care whether its input was parsed from JSON or
KEY=VALUE,... The difference leaks for alternates, as noted in commit
0ee9ae7: a non-string, non-enum scalar alternate value can't currently
be expressed.
In part, this is just our insufficiently sophisticated implementation.
Consider alternate type 'GuestFileWhence'. It has an integer member
and a 'QGASeek' member. The latter is an enumeration with values
'set', 'cur', 'end'. The meaning of b=set, b=cur, b=end, b=0, b=1 and
so forth is perfectly obvious. However, our current implementation
falls apart at run time for b=0, b=1, and so forth. Fixable, but not
today; add a test case and a TODO comment.
Now consider an alternate type with a string and an integer member.
What's the meaning of a=42? Is it the string "42" or the integer 42?
Whichever meaning you pick makes the other inexpressible. This isn't
just an implementation problem, it's fundamental. Our current
implementation will pick string.
So far, we haven't needed such alternates. To make sure we stop and
think before we add one that cannot sanely work with keyval_parse(),
let's require alternate members to have sufficiently distinct
representation in KEY=VALUE,... syntax:
* A string member clashes with any other scalar member
* An enumeration member clashes with bool members when it has value
'on' or 'off'.
* An enumeration member clashes with numeric members when it has a
value that starts with '-', '+', or a decimal digit. This is a
rather lazy approximation of the actual number syntax accepted by
the visitor.
Note that enumeration values starting with '-' and '+' are rejected
elsewhere already, but better safe than sorry.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1495471335-23707-5-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
The next commit is going to make alternate members of type 'str'
conflict with other scalar types. Would break a few test cases that
don't actually require 'str'. Flip them from 'str' to 'bool' or
'EnumOne'.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1495471335-23707-4-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
We have a number of negative tests, but we don't have systematic
positive coverage. Fix that.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1490015515-25851-6-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
test-qapi.py used to print the internal representation of doc comments
(commit 3313b61). This went away when we dropped the doc comments in
positive tests (commit 87c16dc). Bring it back, because I'm going to
add real positive doc comment tests.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1490015515-25851-5-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
When choking on a token where an expression is expected, we report
'Expected "{", "[" or string'. Close, but no cigar. Fix it to
Expected '"{", "[", string, boolean or "null"'.
Missed in commit e53188a.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-48-git-send-email-armbru@redhat.com>
check_definition_doc() checks for member documentation without a
matching member. It laboriously second-guesses what members
QAPISchema._def_exprs() will create. That's a stupid game.
Move the check into QAPISchema.check(), where the members are known.
Delegate the actual checking to new QAPIDoc.check().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-38-git-send-email-armbru@redhat.com>
New test doc-bad-union-member.json shows we can fail to reject
documentation for nonexistent members.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-37-git-send-email-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-36-git-send-email-armbru@redhat.com>
Results in a more precise error location, but the real reason is
emptying out check_docs() step by step.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-35-git-send-email-armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-34-git-send-email-armbru@redhat.com>
Move the check whether the doc matches the expression name from
check_definition_doc() to check_exprs(). This changes the error
location from the comment to the expression. Makes sense as the
message talks about the expression: "Definition of '%s' follows
documentation for '%s'". It's also a step towards getting rid of
check_docs().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-33-git-send-email-armbru@redhat.com>
This fixes the errors uncovered by the previous commit.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-32-git-send-email-armbru@redhat.com>
New tests doc-before-include.json and doc-before-pragma.json show we
fail to reject a misplaced expression comment.
New test doc-no-symbol.json shows a bad error message.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1489582656-31133-31-git-send-email-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
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>
Common Python pitfall: 'assert base_members' fires on [] in addition
to None. Correct to 'assert base_members is not None'.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-10-git-send-email-armbru@redhat.com>
The new test case shows off qapi.py choking on an empty union base.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-9-git-send-email-armbru@redhat.com>
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.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>
This reverts commit 3313b61's changes to tests/qapi-schema/, except
for tests/qapi-schema/doc-*.
We could keep some of these doc comments to serve as positive test
cases. However, they don't actually add to what we get from doc
comment use in actual schemas, as we we don't test output matches
expectations, and don't systematically cover doc comment features.
Proper positive test coverage would be nice.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1489582656-31133-4-git-send-email-armbru@redhat.com>
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>
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>
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>
Clean up the only remaining external use of the tag_name field of
QAPISchemaObjectTypeVariants, by explicitly listing the generated
'type' tag for all variants in the testsuite (you can still tell
simple unions by the -wrapper types). Then we can mark the
tag_name field as private by adding a leading underscore to prevent
any further use.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-5-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
We were previously enforcing that all flat union branches were
found in the corresponding enum, but not that all enum values
were covered by branches. The resulting generated code would
abort() if the user passes the uncovered enum value.
We don't automatically treat non-present branches in a flat
union as empty types, for symmetry with simple unions (there,
the enum type is generated from the list of all branches, so
there is no way to omit a branch but still have it be part of
the union).
A later patch will add shorthand so that branches that are empty
in flat unions can be declared as 'branch':{} instead of
'branch':'Empty', to avoid the need for an otherwise useless
explicit empty type. [Such shorthand for simple unions is a bit
harder to justify, since we would still have to generate a
wrapper type that parses 'data':{}, rather than truly being an
empty branch with no additional siblings to the 'type' member.]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1468468228-27827-3-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
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>
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>
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 started moving away from the use of the 'void *data' member
in the C union corresponding to a QAPI union back in commit
544a373; recent commits have gotten rid of other uses. Now
that it is completely unused, we can remove the member itself
as well as the FIXME comment. Update the testsuite to drop the
negative test union-clash-data.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1457021813-10704-11-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>
Upcoming patches will adjust how we visit an object branch of an
alternate; but we were completely lacking testsuite coverage.
Rectify this, so that the future patches will be able to highlight
the changes and still prove that we avoided regressions.
In particular, the use of a flat union UserDefFlatUnion rather
than a simple struct UserDefA as the branch will give us coverage
of an object with variants. And visiting an alternate as both
the top level and as a nested member gives confidence in correct
memory allocation handling, especially if the test is run under
valgrind.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
The whole point of an alternate is to allow some type-safety while
still accepting more than one JSON type. Meanwhile, the 'any'
type exists to bypass type-safety altogether. The two are
incompatible: you can't accept every type, and still tell which
branch of the alternate to use for the parse; fix this to give a
sane error instead of a Python stack trace.
Note that other types that can't be alternate members are caught
earlier, by check_type().
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-4-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Empty unions serve no purpose, and while we compile with gcc
which permits them, strict C99 forbids them. We happen to inject
a dummy 'void *data' member into the C unions that represent QAPI
unions and alternates, but we want to get rid of that member (it
pollutes the namespace for no good reason), which would leave us
with an empty union if the user didn't provide any branches. While
empty structs make sense in QAPI, empty unions don't add any
expressiveness to the QMP language. So prohibit them at parse
time. Update the documentation and testsuite to match.
Note that the documentation already mentioned that alternates
should have "two or more JSON data types"; so this also fixes
the code to enforce that. However, we have existing uses of a
union type with only one branch, so the 2-or-more strictness
is intentionally limited to alternates.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Markus Armbruster
Daniel P. Berrange
Eduardo Habkost
Marc-André Lureau
Eric Blake