Commit Graph

98 Commits

Author SHA1 Message Date
Markus Armbruster
c4f498fe85 qapi: Generators crash when --output-dir isn't given, fix
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:16 +02:00
Markus Armbruster
eddf817bd8 qapi: Simplify error reporting for array types
check_type() first checks and peels off the array type, then checks
the element type.  For two out of four error messages, it takes pains
to report errors for "array of T" instead of just T.  Odd.  Let's
examine the errors.

* Unknown element type, e.g.
  tests/qapi-schema/args-array-unknown.json:

      Member 'array' of 'data' for command 'oops' uses unknown type
      'array of NoSuchType'

  To make sense of this, you need to know that 'array of NoSuchType'
  refers to '[NoSuchType]'.  Easy enough.  However, simply reporting

      Member 'array' of 'data' for command 'oops' uses unknown type
      'NoSuchType'

  is at least as easy to understand.

* Element type's meta-type is inadmissible, e.g.
  tests/qapi-schema/returns-whitelist.json:

      'returns' for command 'no-way-this-will-get-whitelisted' cannot
      use built-in type 'array of int'

  'array of int' is technically not a built-in type, but that's
  pedantry.  However, simply reporting

      'returns' for command 'no-way-this-will-get-whitelisted' cannot
      use built-in type 'int'

  avoids the issue, and is at least as easy to understand.

* The remaining two errors are unreachable, because the array checking
  ensures that value is a string.

Thus, reporting some errors for "array of T" instead of just T works,
but doesn't really improve things.  Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:16 +02:00
Markus Armbruster
c6b71e5ae7 qapi: Fix errors for non-string, non-dictionary members
Fixes the errors demonstrated by the previous commit.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:16 +02:00
Markus Armbruster
65fbe12545 qapi: Drop one of two "simple union must not have base" checks
The first check ensures the second one can't trigger.  Drop the first
one, because the second one is in a more logical place, and emits a
nicer error message.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:16 +02:00
Markus Armbruster
9b090d42ae qapi: Command returning anonymous type doesn't work, outlaw
Reproducer: with

    { 'command': 'user_def_cmd4', 'returns': { 'a': 'int' } }

added to qapi-schema-test.json, qapi-commands.py dies when it tries to
generate the command handler function

    Traceback (most recent call last):
      File "/work/armbru/qemu/scripts/qapi-commands.py", line 359, in <module>
        ret = generate_command_decl(cmd['command'], arglist, ret_type) + "\n"
      File "/work/armbru/qemu/scripts/qapi-commands.py", line 29, in generate_command_decl
        ret_type=c_type(ret_type), name=c_name(name),
      File "/work/armbru/qemu/scripts/qapi.py", line 927, in c_type
        assert isinstance(value, str) and value != ""
    AssertionError

because the return type doesn't exist.

Simply outlaw this usage, and drop or dumb down test cases accordingly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:15 +02:00
Markus Armbruster
315932b5ed qapi: Fix to reject union command and event arguments
A command's or event's 'data' must be a struct type, given either as a
dictionary, or as struct type name.

Commit dd883c6 tightened the checking there, but not enough: we still
accept 'union'.  Fix to reject it.

We may want to support union types there, but we'll have to extend
qapi-commands.py and qapi-events.py for it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:15 +02:00
Markus Armbruster
d90675fa4b qapi: Document flaws in checking of names
We don't actually enforce our "other than downstream extensions [...],
all names should begin with a letter" rule.  Add a FIXME.

We should reject names that differ only in '_' vs. '.'  vs. '-',
because they're liable to clash in generated C.  Add a FIXME.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:14 +02:00
Markus Armbruster
5aa05d3f72 qapi: Drop unused and useless parameters and variables
gen_sync_call()'s parameter indent is useless: gen_sync_call() uses it
only as optional argument for push_indent() and pop_indent(), their
default is four, and gen_sync_call()'s only caller passes four.  Drop
the parameter.

gen_visitor_input_containers_decl()'s parameter obj is always
"QOBJECT(args)".  Use that, and drop the parameter.

Drop unused parameters of gen_marshal_output(),
gen_marshal_input_decl(), generate_visit_struct_body(),
generate_visit_list(), generate_visit_enum(), generate_declaration(),
generate_enum_declaration(), generate_decl_enum().

Drop unused variables in generate_event_enum_lookup(),
generate_enum_lookup(), generate_visit_struct_fields(), check_event().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:13 +02:00
Markus Armbruster
1cf47a15f1 qapi: Reject -p arguments that break qapi-event.py
qapi-event.py breaks when you ask for a funny prefix like '@'.
Protect it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:13 +02:00
Markus Armbruster
00dfc3b2c2 qapi: Simplify guardname()
The guards around built-in declarations lose their _H.  It never made
much sense anyway.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:13 +02:00
Markus Armbruster
77e703b861 qapi: Clean up cgen() and mcgen()
Commit 05dfb26 added eatspace stripping to mcgen().  Move it to
cgen(), just in case somebody gets tempted to use cgen() directly
instead of via mcgen().

cgen() indents blank lines.  No such lines get generated right now,
but fix it anyway.

We use triple-quoted strings for program text, like this:

    '''
    Program text
    any number of lines
    '''

Keeps the program text relatively readable, but puts an extra newline
at either end.  mcgen() "fixes" that by dropping the first and last
line outright.  Drop only the newlines.

This unmasks a bug in qapi-commands.py: four quotes instead of three.
Fix it up.

Output doesn't change

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-04 15:47:13 +02:00
Markus Armbruster
f9a1427361 qapi: Catch and reject flat union branch of array type
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:19:47 +02:00
Markus Armbruster
00e4b285a3 qapi: Better separate the different kinds of helpers
Insert comments to separate sections dealing with parsing, semantic
analysis, code generation, and so forth.

Move helpers to their proper section.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:19:47 +02:00
Markus Armbruster
4d076d67c2 qapi: Move exprs checking from parse_schema() to check_exprs()
To have expression semantic analysis in one place rather than two.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:19:47 +02:00
Markus Armbruster
e565d934d2 qapi: Fix to reject stray 't', 'f' and 'n'
Screwed up in commit e53188a.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:19:34 +02:00
Markus Armbruster
a136608727 qapi: Simplify inclusion cycle detection
We maintain a stack of filenames in include_hist for convenient cycle
detection.

As error_path() demonstrates, the same information is readily
available in the expr_info, so just use that, and drop include_hist.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:12:34 +02:00
Markus Armbruster
8608d25251 qapi: Fix file name in error messages for included files
We print the name as it appears in the include expression.  Tools
processing error messages want it relative to the working directory.
Make it so.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:12:34 +02:00
Markus Armbruster
54414047ec qapi: Improve a couple of confusing variable names
old name      new name
----------------------------
input_file    fname
input_relname fname
input_fname   abs_fname
include_path  incl_abs_fname
parent_info   incl_info

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:12:34 +02:00
Markus Armbruster
12c7079449 qapi: Eliminate superfluous QAPISchema attribute input_dir
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-06-18 14:12:33 +02:00
Markus Armbruster
09896d3f48 qapi: Drop pointless flush() before close()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:41:32 +02:00
Markus Armbruster
12f8e1b9ff qapi: Factor open_output(), close_output() out of generators
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:41:32 +02:00
Markus Armbruster
16d80f6181 qapi: Turn generators' mandatory option -i into an argument
Mandatory option is silly, and the error handling is missing: the
programs crash when -i isn't supplied.  Make it an argument, and check
it properly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:41:23 +02:00
Markus Armbruster
b45409683e qapi: Fix generators to report command line errors decently
Report to stderr, prefix with the program name.  Also reject
extra arguments.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:39:34 +02:00
Markus Armbruster
2114f5a98d qapi: Factor parse_command_line() out of the generators
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:37:14 +02:00
Eric Blake
c6405b54b7 qapi: Make c_type() consistently convert qapi names
Continuing the string of cleanups for supporting downstream names
containing '.', this patch focuses on ensuring c_type() can
handle a downstream name.  This patch alone does not fix the
places where generator output should be calling this function
but was open-coding things instead, but it gets us a step closer.

In particular, the changes to c_list_type() and type_name() mean
that type_name(FOO) now handles the case when FOO contains '.',
'-', or is a ticklish identifier other than a builtin (builtins
are exempted because ['int'] must remain mapped to 'intList' and
not 'q_intList').  Meanwhile, ['unix'] now maps to 'q_unixList'
rather than 'unixList', to match the fact that 'unix' is ticklish;
however, our naming conventions state that complex types should
start with a capital, so no type name following conventions will
ever have the 'q_' prepended.

Likewise, changes to c_type() mean that c_type(FOO) properly
handles an enum or complex type FOO with '.' or '-' in the
name, or is a ticklish identifier (again, a ticklish identifier
as a type name violates conventions).

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-14 18:21:07 +02:00
Eric Blake
d557344628 qapi: Tidy c_type() logic
c_type() is designed to be called on both string names and on
array designations, so 'name' is a bit misleading because it
operates on more than strings.  Also, no caller ever passes
an empty string.  Finally, + notation is a bit nicer to read
than '%s' % value for string concatenation.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-14 18:21:03 +02:00
Markus Armbruster
849bc5382e qapi: Move camel_to_upper(), c_enum_const() to closely related code
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:21:00 +02:00
Markus Armbruster
b42e91484d qapi: Use c_enum_const() in generate_alternate_qtypes()
Missed in commit b0b5819.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:20:57 +02:00
Markus Armbruster
02e20c7e59 qapi: Simplify c_enum_const()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:20:54 +02:00
Markus Armbruster
7c81c61f9c qapi: Rename generate_enum_full_value() to c_enum_const()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:20:51 +02:00
Markus Armbruster
fa6068a1e8 qapi: Rename _generate_enum_string() to camel_to_upper()
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2015-05-14 18:20:48 +02:00
Eric Blake
18df515ebb qapi: Rename identical c_fun()/c_var() into c_name()
Now that the two functions are identical, we only need one of them,
and we might as well give it a more descriptive name.  Basically,
the function serves as the translation from a QAPI name into a
(portion of a) C identifier, without regards to whether it is a
variable or function name.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-14 18:20:42 +02:00
Markus Armbruster
47299262de qapi: Fix C identifiers generated for names containing '.'
c_fun() maps '.' to '_', c_var() doesn't.  Nothing prevents '.' in
QAPI names that get passed to c_var().

Which QAPI names get passed to c_fun(), to c_var(), or to both is not
obvious.  Names of command parameters and struct type members get
passed to c_var().

c_var() strips a leading '*', but this cannot happen.  c_fun()
doesn't.

Fix c_var() to work exactly like c_fun().

Perhaps they should be replaced by a single mapping function.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[add 'import string']
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
2015-05-14 18:20:29 +02:00
Eric Blake
ff55d72eaf qapi: Check for member name conflicts with a base class
Our type inheritance for both 'struct' and for flat 'union' merges
key/value pairs from the base class with those from the type in
question.  Although the C code currently boxes things so that there
is a distinction between which member is referred to, the QMP wire
format does not allow passing a key more than once in a single
object.  Besides, if we ever change the generated C code to not be
quite so boxy, we'd want to avoid duplicate member names there,
too.

Fix a testsuite entry added in an earlier patch, as well as adding
a couple more tests to ensure we have appropriate coverage.  Ensure
that collisions are detected, regardless of whether there is a
difference in opinion on whether the member name is optional.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:02 +02:00
Eric Blake
a7f5966b29 qapi: Support (subset of) \u escapes in strings
The handling of \ inside QAPI strings was less than ideal, and
really only worked JSON's \/, \\, \", and our extension of \'
(an obvious extension, when you realize we use '' instead of ""
for strings).  For other things, like '\n', it resulted in a
literal 'n' instead of a newline.

Of course, at the moment, we really have no use for escaped
characters, as QAPI has to map to C identifiers, and we currently
support ASCII only for that.  But down the road, we may add
support for default values for string parameters to a command
or struct; if that happens, it would be nice to correctly support
all JSON escape sequences, such as \n or \uXXXX.  This gets us
closer, by supporting Unicode escapes in the ASCII range.

Since JSON does not require \OCTAL or \xXX escapes, and our QMP
implementation does not understand them either, I intentionally
reject it here, but it would be an easy addition if we desired it.
Likewise, intentionally refusing the NUL byte means we don't have
to worry about C strings being shorter than the qapi input.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:02 +02:00
Eric Blake
6b5abc7df7 qapi: Drop support for inline nested types
A future patch will be using a 'name':{dictionary} entry in the
QAPI schema to specify a default value for an optional argument
(see previous commit messages for more details why); but existing
use of inline nested structs conflicts with that goal. Now that
all commands have been changed to avoid inline nested structs,
nuke support for them, and turn it into a hard error. Update the
testsuite to reflect tighter parsing rules.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:02 +02:00
Eric Blake
3e391d3556 qapi: Forbid 'type' in schema
Referring to "type" as both a meta-type (built-in, enum, union,
alternate, or struct) and a specific type (the name that the
schema uses for declaring structs) is confusing.  Finish up the
conversion to using "struct" in qapi schema by removing the hack
in the generator that allowed 'type'.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
fd41dd4eae qapi: Prefer 'struct' over 'type' in generator
Referring to "type" as both a meta-type (built-in, enum, union,
alternate, or struct) and a specific type (the name that the
schema uses for declaring structs) is confusing.  The confusion
is only made worse by the fact that the generator mostly already
refers to struct even when dealing with expr['type'].  This
commit changes the generator to consistently refer to it as
struct everywhere, plus a single back-compat tweak that allows
accepting the existing .json files as-is, so that the meat of
this change is separate from the mindless churn of that change.

Fix the testsuite fallout for error messages that change, and
in some cases, become more legible.  Improve comments to better
match our intentions where a struct (rather than any complex
type) is required.  Note that in some cases, an error message
now refers to 'struct' while the schema still refers to 'type';
that will be cleaned up in the later commit to the schema.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
2cbf09925a qapi: More rigorous checking for type safety bypass
Now that we have a way to validate every type, we can also be
stricter about enforcing that callers that want to bypass
type safety in generated code.  Prior to this patch, it didn't
matter what value was associated with the key 'gen', but it
looked odd that 'gen':'yes' could result in bypassing the
generated code.  These changes also enforce the changes made
earlier in the series for documentation and consolidation of
using '**' as the wildcard type, as well as 'gen':false as the
canonical spelling for requesting type bypass.

Note that 'gen':false is a one-way switch away from the default;
we do not support 'gen':true (similar for 'success-response').
In practice, this doesn't matter.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
10d4d997f8 qapi: Whitelist commands that don't return dictionary
...or an array of dictionaries.  Although we have to cater to
existing commands, returning a non-dictionary means the command
is not extensible (no new name/value pairs can be added if more
information must be returned in parallel).  By making the
whitelist explicit, any new command that falls foul of this
practice will have to be self-documenting, which will encourage
developers to either justify the action or rework the design to
use a dictionary after all.

It's a little bit sloppy that we share a single whitelist among
three clients (it's too permissive for each).  If this is a
problem, a future patch could tighten things by having the
generator take the whitelist as an argument (as in
scripts/qapi-commands.py --legacy-returns=...), or by having
the generator output C code that requires explicit use of the
whitelist (as in:
 #ifndef FROBNICATE_LEGACY_RETURN_OK
 # error Command 'frobnicate' should return a dictionary
 #endif
then having the callers define appropriate macros).  But until
we need such fine-grained separation (if ever), this patch does
the job just fine.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
c9e0a79869 qapi: Require valid names
Previous commits demonstrated that the generator overlooked various
bad naming situations:
- types, commands, and events need a valid name
- enum members must be valid names, when combined with prefix
- union and alternate branches cannot be marked optional

Valid upstream names match [a-zA-Z][a-zA-Z0-9_-]*; valid downstream
names match __[a-zA-Z][a-zA-Z0-9._-]*.  Enumerations match the
weaker [a-zA-Z0-9._-]+ (in part thanks to QKeyCode picking an enum
that starts with a digit, which we can't change now due to
backwards compatibility).  Rather than call out three separate
regex, this patch just uses a broader combination that allows both
upstream and downstream names, as well as a small hack that
realizes that any enum name is merely a suffix to an already valid
name prefix (that is, any enum name is valid if prepending _ fits
the normal rules).

We could reject new enumeration names beginning with a digit by
whitelisting existing exceptions.  We could also be stricter
about the distinction between upstream names (no leading
underscore, no use of dot) and downstream (mandatory leading
double underscore), but it is probably not worth the bother.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
dd883c6f05 qapi: More rigourous checking of types
Now that we know every expression is valid with regards to
its keys, we can add further tests that those keys refer to
valid types.  With this patch, all uses of a type (the 'data':
of command, type, union, alternate, and event; the 'returns':
of command; the 'base': of type and union) must resolve to an
appropriate subset of metatypes  declared by the current qapi
parse; this includes recursing into each member of a data
dictionary.  Dealing with '**' and nested anonymous structs
will be done in later patches.

Update the testsuite to match improved output.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Fam Zheng
e53188ada5 qapi: Allow true, false and null in schema json
In the near term, we will use it for a sensible-looking
'gen':false inside command declarations, instead of the
current ugly 'gen':'no'.

In the long term, it will allow conversion from shorthand
with defaults mentioned only in side-band documentation:
 'data':{'*flag':'bool', '*string':'str'}
into an explicit default value documentation, as in:
 'data':{'flag':{'type':'bool', 'optional':true, 'default':true},
         'string':{'type':'str', 'optional':true, 'default':null}}

We still don't parse integer values (also necessary before
we can allow explicit defaults), but that can come in a later
series.

Update the testsuite to match an improved error message.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
4dc2e6906e qapi: Better error messages for duplicated expressions
The previous commit demonstrated that the generator overlooked
duplicate expressions:
- a complex type or command reusing a built-in type name
- redeclaration of a type name, whether by the same or different
metatype
- redeclaration of a command or event
- collision of a type with implicit 'Kind' enum for a union
- collision with an implicit MAX enum constant

Since the c_type() function in the generator treats all names
as being in the same namespace, this patch adds a global array
to track all known names and their source, to prevent collisions
before it can cause further problems.  While valid .json files
won't trigger any of these cases, we might as well be nicer to
developers that make a typo while trying to add new QAPI code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
0545f6b887 qapi: Better error messages for bad expressions
The previous commit demonstrated that the generator overlooked some
fairly basic broken expressions:
- missing metataype
- metatype key has a non-string value
- unknown key in relation to the metatype
- conflicting metatype (this patch treats the second metatype as an
unknown key of the first key visited, which is not necessarily the
first key the user typed)

Add check_keys to cover these situations, and update testcases to
match.  A couple other tests (enum-missing-data, indented-expr) had
to change since the validation added here occurs so early.
Conversely, changes to ident-with-escape results show that we still
have problems where our handling of escape sequences differs from
true JSON, which will matter down the road if we allow arbitrary
default string values for optional parameters (but for now is not
too bad, as we currently can avoid unicode escaping as we don't
need to represent anything beyond C identifier material).

While valid .json files won't trigger any of these cases, we might
as well be nicer to developers that make a typo while trying to add
new QAPI code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:01 +02:00
Eric Blake
ab916faddd qapi: Use 'alternate' to replace anonymous union
Previous patches have led up to the point where I create the
new meta-type "'alternate':'Foo'".  See the previous patches
for documentation; I intentionally split as much work into
earlier patches to minimize the size of this patch, but a lot
of it is churn due to testsuite fallout after updating to the
new type.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:00 +02:00
Eric Blake
811d04fd0c qapi: Segregate anonymous unions into alternates in generator
Special-casing 'discriminator == {}' for handling anonymous unions
is getting awkward; since this particular type is not always a
dictionary on the wire, it is easier to treat it as a completely
different class of type, "alternate", so that if a type is listed
in the union_types array, we know it is not an anonymous union.

This patch just further segregates union handling, to make sure that
anonymous unions are not stored in union_types, and splitting up
check_union() into separate functions.  A future patch will change
the qapi grammar, and having the segregation already in place will
make it easier to deal with the distinct meta-type.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:00 +02:00
Eric Blake
268a1c5eb1 qapi: Prepare for catching more semantic parse errors
This patch widens the scope of a try block (with the attending
reindentation required by Python) in preparation for a future
patch adding more instances of QAPIExprError inside the block.
It's easier to separate indentation from semantic changes, so
this patch has no real behavior change.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:00 +02:00
Eric Blake
44bd1276a7 qapi: Tighten checking of unions
Previous commits demonstrated that the generator had several
flaws with less-than-perfect unions:
- a simple union that listed the same branch twice (or two variant
names that map to the same C enumerator, including the implicit
MAX sentinel) ended up generating invalid C code
- an anonymous union that listed two branches with the same qtype
ended up generating invalid C code
- the generator crashed on anonymous union attempts to use an
array type
- the generator was silently ignoring a base type for anonymous
unions
- the generator allowed unknown types or nested anonymous unions
as a branch in an anonymous union

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:00 +02:00
Eric Blake
a8d4a2e4d7 qapi: Forbid base without discriminator in unions
None of the existing QMP or QGA interfaces uses a union with a
base type but no discriminator; it is easier to avoid this in the
generator to save room for other future extensions more likely to
be useful.  An earlier commit added a union-base-no-discriminator
test to ensure that we eventually give a decent error message;
likewise, removing UserDefUnion outright is okay, because we moved
all the tests we wish to keep into the tests of the simple union
UserDefNativeListUnion in the previous commit.  Now is the time to
actually forbid simple union with base, and remove the last
vestiges from the testsuite.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2015-05-05 18:39:00 +02:00