Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2021-08-26' into staging

QAPI patches patches for 2021-08-26

# gpg: Signature made Thu 26 Aug 2021 13:18:34 BST
# gpg:                using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg:                issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [full]
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>" [full]
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-qapi-2021-08-26:
  qapi: make 'if' condition strings simple identifiers
  qapi: add 'not' condition operation
  qapi: Use 'if': { 'any': ... } where appropriate
  qapi: add 'any' condition
  qapi: replace if condition list with dict {'all': [...]}
  qapidoc: introduce QAPISchemaIfCond.docgen()
  qapi: introduce QAPISchemaIfCond.cgen()
  qapi: add QAPISchemaIfCond.is_present()
  qapi: wrap Sequence[str] in an object
  docs: update the documentation upfront about schema configuration
  qapi: Fix crash on redefinition with a different condition

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 63 insertions, 35 deletions

diff --git a/scripts/qapi/schema.py b/scripts/qapi/schema.py
index d1d27ff7ee..229d24fce9 100644
--- a/scripts/qapi/schema.py
+++ b/scripts/qapi/schema.py
@@ -19,12 +19,31 @@ import os
 import re
 from typing import Optional
 
-from .common import POINTER_SUFFIX, c_name
+from .common import (
+    POINTER_SUFFIX,
+    c_name,
+    cgen_ifcond,
+    docgen_ifcond,
+)
 from .error import QAPIError, QAPISemError, QAPISourceError
 from .expr import check_exprs
 from .parser import QAPISchemaParser
 
 
+class QAPISchemaIfCond:
+    def __init__(self, ifcond=None):
+        self.ifcond = ifcond or {}
+
+    def cgen(self):
+        return cgen_ifcond(self.ifcond)
+
+    def docgen(self):
+        return docgen_ifcond(self.ifcond)
+
+    def is_present(self):
+        return bool(self.ifcond)
+
+
 class QAPISchemaEntity:
     meta: Optional[str] = None
 
@@ -42,7 +61,7 @@ class QAPISchemaEntity:
         # such place).
         self.info = info
         self.doc = doc
-        self._ifcond = ifcond or []
+        self._ifcond = ifcond or QAPISchemaIfCond()
         self.features = features or []
         self._checked = False
 
@@ -593,7 +612,7 @@ class QAPISchemaVariants:
                     self.info,
                     "discriminator member '%s' of %s must not be optional"
                     % (self._tag_name, base))
-            if self.tag_member.ifcond:
+            if self.tag_member.ifcond.is_present():
                 raise QAPISemError(
                     self.info,
                     "discriminator member '%s' of %s must not be conditional"
@@ -601,7 +620,7 @@ class QAPISchemaVariants:
         else:                   # simple union
             assert isinstance(self.tag_member.type, QAPISchemaEnumType)
             assert not self.tag_member.optional
-            assert self.tag_member.ifcond == []
+            assert not self.tag_member.ifcond.is_present()
         if self._tag_name:    # flat union
             # branches that are not explicitly covered get an empty type
             cases = {v.name for v in self.variants}
@@ -646,7 +665,7 @@ class QAPISchemaMember:
         assert isinstance(name, str)
         self.name = name
         self.info = info
-        self.ifcond = ifcond or []
+        self.ifcond = ifcond or QAPISchemaIfCond()
         self.defined_in = None
 
     def set_defined_in(self, name):
@@ -968,11 +987,13 @@ class QAPISchema:
     def _make_features(self, features, info):
         if features is None:
             return []
-        return [QAPISchemaFeature(f['name'], info, f.get('if'))
+        return [QAPISchemaFeature(f['name'], info,
+                                  QAPISchemaIfCond(f.get('if')))
                 for f in features]
 
     def _make_enum_members(self, values, info):
-        return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
+        return [QAPISchemaEnumMember(v['name'], info,
+                                     QAPISchemaIfCond(v.get('if')))
                 for v in values]
 
     def _make_implicit_enum_type(self, name, info, ifcond, values):
@@ -997,18 +1018,18 @@ class QAPISchema:
         name = 'q_obj_%s-%s' % (name, role)
         typ = self.lookup_entity(name, QAPISchemaObjectType)
         if typ:
-            # The implicit object type has multiple users.  This can
-            # happen only for simple unions' implicit wrapper types.
-            # Its ifcond should be the disjunction of its user's
-            # ifconds.  Not implemented.  Instead, we always pass the
-            # wrapped type's ifcond, which is trivially the same for all
-            # users.  It's also necessary for the wrapper to compile.
-            # But it's not tight: the disjunction need not imply it.  We
-            # may end up compiling useless wrapper types.
+            # The implicit object type has multiple users.  This is
+            # either a duplicate definition (which will be flagged
+            # later), or an implicit wrapper type used for multiple
+            # simple unions.  In the latter case, ifcond should be the
+            # disjunction of its user's ifconds.  Not implemented.
+            # Instead, we always pass the wrapped type's ifcond, which
+            # is trivially the same for all users.  It's also
+            # necessary for the wrapper to compile.  But it's not
+            # tight: the disjunction need not imply it.  We may end up
+            # compiling useless wrapper types.
             # TODO kill simple unions or implement the disjunction
-
-            # pylint: disable=protected-access
-            assert (ifcond or []) == typ._ifcond
+            pass
         else:
             self._def_entity(QAPISchemaObjectType(
                 name, info, None, ifcond, None, None, members, None))
@@ -1018,7 +1039,7 @@ class QAPISchema:
         name = expr['enum']
         data = expr['data']
         prefix = expr.get('prefix')
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         self._def_entity(QAPISchemaEnumType(
             name, info, doc, ifcond, features,
@@ -1036,7 +1057,8 @@ class QAPISchema:
                                           self._make_features(features, info))
 
     def _make_members(self, data, info):
-        return [self._make_member(key, value['type'], value.get('if'),
+        return [self._make_member(key, value['type'],
+                                  QAPISchemaIfCond(value.get('if')),
                                   value.get('features'), info)
                 for (key, value) in data.items()]
 
@@ -1044,7 +1066,7 @@ class QAPISchema:
         name = expr['struct']
         base = expr.get('base')
         data = expr['data']
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         self._def_entity(QAPISchemaObjectType(
             name, info, doc, ifcond, features, base,
@@ -1067,7 +1089,7 @@ class QAPISchema:
         name = expr['union']
         data = expr['data']
         base = expr.get('base')
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         tag_name = expr.get('discriminator')
         tag_member = None
@@ -1076,15 +1098,19 @@ class QAPISchema:
                 name, info, ifcond,
                 'base', self._make_members(base, info))
         if tag_name:
-            variants = [self._make_variant(key, value['type'],
-                                           value.get('if'), info)
-                        for (key, value) in data.items()]
+            variants = [
+                self._make_variant(key, value['type'],
+                                   QAPISchemaIfCond(value.get('if')),
+                                   info)
+                for (key, value) in data.items()]
             members = []
         else:
-            variants = [self._make_simple_variant(key, value['type'],
-                                                  value.get('if'), info)
-                        for (key, value) in data.items()]
-            enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
+            variants = [
+                self._make_simple_variant(key, value['type'],
+                                          QAPISchemaIfCond(value.get('if')),
+                                          info)
+                for (key, value) in data.items()]
+            enum = [{'name': v.name, 'if': v.ifcond.ifcond} for v in variants]
             typ = self._make_implicit_enum_type(name, info, ifcond, enum)
             tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
             members = [tag_member]
@@ -1097,11 +1123,13 @@ class QAPISchema:
     def _def_alternate_type(self, expr, info, doc):
         name = expr['alternate']
         data = expr['data']
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
-        variants = [self._make_variant(key, value['type'], value.get('if'),
-                                       info)
-                    for (key, value) in data.items()]
+        variants = [
+            self._make_variant(key, value['type'],
+                               QAPISchemaIfCond(value.get('if')),
+                               info)
+            for (key, value) in data.items()]
         tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
         self._def_entity(
             QAPISchemaAlternateType(name, info, doc, ifcond, features,
@@ -1118,7 +1146,7 @@ class QAPISchema:
         allow_oob = expr.get('allow-oob', False)
         allow_preconfig = expr.get('allow-preconfig', False)
         coroutine = expr.get('coroutine', False)
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
@@ -1137,7 +1165,7 @@ class QAPISchema:
         name = expr['event']
         data = expr.get('data')
         boxed = expr.get('boxed', False)
-        ifcond = expr.get('if')
+        ifcond = QAPISchemaIfCond(expr.get('if'))
         features = self._make_features(expr.get('features'), info)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(