[Qemu-devel] [PATCH v4 10/10] qapi: Populate info['name'] for each entity

[Eric Blake <eblake@redhat.com>]

Every non-implicit entity is associated with an 'info'
dictionary, but it is not easy to reverse-engineer the name of
the top-most entity associated with that 'info'.  Our use of
'case_whitelist' (added in commit 893e1f2) is thus currently
tied to the owner of a member instead; but as the previous patch
showed with CpuInfo, this requires whitelist exceptions to know
how an implicit name will be generated.

While we have a ._pretty_owner() that maps from implicit names
back to a human readable phrase, that produces more than just a
plain top-level entity name.  What's more, the current use of
._pretty_owner() is via .check_clash(), which can be called on
the same member object more than once (once through the
standalone type, and a second time when used as a base class of
a derived tpye); if a clash is only introduced in the derived
class, using ._pretty_owner() to report the error on behalf of
the base class named in member.owner seems wrong.  Therefore,
we need a new mechanism.

Add a new info['name'] field to track the information we need,
allowing us to change 'case_whitelist' to use only names present
in the qapi files.

Unfortunately, there is no one good place to add the mapping:
at the point 'info' is created in QAPISchemaParser.__init__(),
we don't know the name.  Info is then stored into
QAPISchemaParser.exprs, which then then gets fed to
QAPISchema.__init__() via the global check_exprs(), but we want
check_exprs() to go away.  And QAPISchema._def_exprs() sees
every entity, except that the various _def_FOO() helpers don't
return anything.  So we have to modify all of the _def_FOO()
methods.

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v4: Change series again :)
[previously posted in subset F]:
v6: sink later in series, and rework commit message
[previously posted in subset D]:
v14: rearrange assignment, improve commit message
v13: new patch
---
 scripts/qapi.py | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/scripts/qapi.py b/scripts/qapi.py
index ebcd207..6c991c3 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -62,8 +62,8 @@ returns_whitelist = [
 # Whitelist of entities allowed to violate case conventions
 case_whitelist = [
     # From QMP:
-    ':obj-CpuInfo-base',    # CPU, visible through query-cpu
     'ACPISlotType',         # DIMM, visible through query-acpi-ospm-status
+    'CpuInfo',              # CPU and PC, visible through query-cpu
     'CpuInfoMIPS',          # PC, visible through query-cpu
     'CpuInfoTricore',       # PC, visible through query-cpu
     'QapiErrorClass',       # all members, visible through errors
@@ -1035,7 +1035,7 @@ class QAPISchemaMember(object):

     def check_clash(self, info, seen):
         cname = c_name(self.name)
-        if cname.lower() != cname and self.owner not in case_whitelist:
+        if cname.lower() != cname and info['name'] not in case_whitelist:
             raise QAPIExprError(info,
                                 "%s should not use uppercase" % self.describe())
         if cname in seen:
@@ -1296,7 +1296,7 @@ class QAPISchema(object):
         return name

     def _def_enum_type(self, expr, info):
-        name = expr['enum']
+        name = info['name'] = expr['enum']
         data = expr['data']
         prefix = expr.get('prefix')
         self._def_entity(QAPISchemaEnumType(
@@ -1317,7 +1317,7 @@ class QAPISchema(object):
                 for (key, value) in data.iteritems()]

     def _def_struct_type(self, expr, info):
-        name = expr['struct']
+        name = info['name'] = expr['struct']
         base = expr.get('base')
         data = expr['data']
         self._def_entity(QAPISchemaObjectType(name, info, base,
@@ -1336,7 +1336,7 @@ class QAPISchema(object):
         return QAPISchemaObjectTypeVariant(case, typ)

     def _def_union_type(self, expr, info):
-        name = expr['union']
+        name = info['name'] = expr['union']
         data = expr['data']
         base = expr.get('base')
         tag_name = expr.get('discriminator')
@@ -1362,7 +1362,7 @@ class QAPISchema(object):
                                                               variants)))

     def _def_alternate_type(self, expr, info):
-        name = expr['alternate']
+        name = info['name'] = expr['alternate']
         data = expr['data']
         variants = [self._make_variant(key, value)
                     for (key, value) in data.iteritems()]
@@ -1374,7 +1374,7 @@ class QAPISchema(object):
                                                                  variants)))

     def _def_command(self, expr, info):
-        name = expr['command']
+        name = info['name'] = expr['command']
         data = expr.get('data')
         rets = expr.get('returns')
         gen = expr.get('gen', True)
@@ -1389,7 +1389,7 @@ class QAPISchema(object):
                                            success_response))

     def _def_event(self, expr, info):
-        name = expr['event']
+        name = info['name'] = expr['event']
         data = expr.get('data')
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
-- 
2.5.0