qapi.py: Fix diagnosing non-objects at a schema's top-level

Report syntax error instead of crashing.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1374939721-7876-8-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

scripts/qapi.py

@@ -64,7 +64,7 @@ def __init__(self, fp):
         self.accept()
 
         while self.tok != None:
-            self.exprs.append(self.get_expr())
+            self.exprs.append(self.get_expr(False))
 
     def accept(self):
         while True:
@@ -117,7 +117,7 @@ def get_members(self):
             if self.tok != ':':
                 raise QAPISchemaError(self, 'Expected ":"')
             self.accept()
-            expr[key] = self.get_expr()
+            expr[key] = self.get_expr(True)
             if self.tok == '}':
                 self.accept()
                 return expr
@@ -135,7 +135,7 @@ def get_values(self):
         if not self.tok in [ '{', '[', "'" ]:
             raise QAPISchemaError(self, 'Expected "{", "[", "]" or string')
         while True:
-            expr.append(self.get_expr())
+            expr.append(self.get_expr(True))
             if self.tok == ']':
                 self.accept()
                 return expr
@@ -143,7 +143,9 @@ def get_values(self):
                 raise QAPISchemaError(self, 'Expected "," or "]"')
             self.accept()
 
-    def get_expr(self):
+    def get_expr(self, nested):
+        if self.tok != '{' and not nested:
+            raise QAPISchemaError(self, 'Expected "{"')
         if self.tok == '{':
             self.accept()
             expr = self.get_members()

tests/qapi-schema/non-objects.err

@@ -1 +1 @@
-Crashed: <type 'exceptions.AttributeError'>
+<stdin>:1:1: Expected "{"

tests/qapi-schema/quoted-structural-chars.err

@@ -1 +1 @@
-Crashed: <type 'exceptions.AttributeError'>
+<stdin>:1:1: Expected "{"