Re: [PATCH 7/9] qapi: Generalize enum member policy checking

John Snow <jsnow(a)redhat.com&gt; writes: > On Mon, Oct 25, 2021 at 1:26 AM Markus Armbruster <armbru(a)redhat.com&gt; wrote: > >> The code to check enumeration value policy can see special feature >> flag 'deprecated' in QEnumLookup member flags[value]. I want to make >> feature flag 'unstable' visible there as well, so I can add policy for >> it. >> >> Instead of extending flags[], replace it by @special_features (a >> bitset of QapiSpecialFeature), because that's how special features get >> passed around elsewhere. >> >> Signed-off-by: Markus Armbruster <armbru(a)redhat.com&gt; >> --- >> include/qapi/util.h | 5 +---- >> qapi/qapi-visit-core.c | 3 ++- >> scripts/qapi/types.py | 22 ++++++++++++---------- >> 3 files changed, 15 insertions(+), 15 deletions(-) >> >> diff --git a/include/qapi/util.h b/include/qapi/util.h >> index 7a8d5c7d72..0cc98db9f9 100644 >> --- a/include/qapi/util.h >> +++ b/include/qapi/util.h >> @@ -15,12 +15,9 @@ typedef enum { >> QAPI_DEPRECATED, >> } QapiSpecialFeature; >> >> -/* QEnumLookup flags */ >> -#define QAPI_ENUM_DEPRECATED 1 >> - >> typedef struct QEnumLookup { >> const char *const *array; >> - const unsigned char *const flags; >> + const unsigned char *const special_features; >> const int size; >> } QEnumLookup; >> >> diff --git a/qapi/qapi-visit-core.c b/qapi/qapi-visit-core.c >> index b4a81f1757..5572d90efb 100644 >> --- a/qapi/qapi-visit-core.c >> +++ b/qapi/qapi-visit-core.c >> @@ -407,7 +407,8 @@ static bool input_type_enum(Visitor *v, const char >> *name, int *obj, >> return false; >> } >> >> - if (lookup->flags && (lookup->flags[value] & QAPI_ENUM_DEPRECATED)) { >> + if (lookup->special_features >> + && (lookup->special_features[value] & QAPI_DEPRECATED)) { >> switch (v->compat_policy.deprecated_input) { >> case COMPAT_POLICY_INPUT_ACCEPT: >> break; >> diff --git a/scripts/qapi/types.py b/scripts/qapi/types.py >> index ab2441adc9..3013329c24 100644 >> --- a/scripts/qapi/types.py >> +++ b/scripts/qapi/types.py >> @@ -16,7 +16,7 @@ >> from typing import List, Optional >> >> from .common import c_enum_const, c_name, mcgen >> -from .gen import QAPISchemaModularCVisitor, ifcontext >> +from .gen import QAPISchemaModularCVisitor, gen_special_features, >> ifcontext >> from .schema import ( >> QAPISchema, >> QAPISchemaEnumMember, >> @@ -39,7 +39,7 @@ def gen_enum_lookup(name: str, >> members: List[QAPISchemaEnumMember], >> prefix: Optional[str] = None) -> str: >> max_index = c_enum_const(name, '_MAX', prefix) >> - flags = '' >> + feats = '' >> ret = mcgen(''' >> >> const QEnumLookup %(c_name)s_lookup = { >> @@ -54,19 +54,21 @@ def gen_enum_lookup(name: str, >> ''', >> index=index, name=memb.name) >> ret += memb.ifcond.gen_endif() >> - if 'deprecated' in (f.name for f in memb.features): >> - flags += mcgen(''' >> - [%(index)s] = QAPI_ENUM_DEPRECATED, >> -''', >> - index=index) >> >> - if flags: >> + special_features = gen_special_features(memb.features) >> + if special_features != '0': >> > > Though, I have to admit the common reoccurrence of this pattern suggests to > me that gen_special_features really ought to be returning something false-y > in these cases. Something about testing for the empty case with something > that represents, but isn't empty, gives me a brief pause. > > Not willing to wage war over it. I habitually start stupid, and when stupid confuses or annoys me later, I smarten it up some. Let's see how this instance of "stupid" ages, okay?

>> + feats += mcgen(''' >> + [%(index)s] = %(special_features)s, >> +''', >> + index=index, special_features=special_features) >> + >> + if feats: >> ret += mcgen(''' >> }, >> - .flags = (const unsigned char[%(max_index)s]) { >> + .special_features = (const unsigned char[%(max_index)s]) { >> ''', >> max_index=max_index) >> - ret += flags >> + ret += feats >> >> ret += mcgen(''' >> }, >> -- >> 2.31.1 >> >> > Python bits: Acked-by: John Snow <jsnow(a)redhat.com&gt; Thanks!