qapi: Change data type of the FOO_lookup generated for enum FOO

Currently, a FOO_lookup is an array of strings terminated by a NULL
sentinel.

A future patch will generate enums with "holes".  NULL-termination
will cease to work then.

To prepare for that, store the length in the FOO_lookup by wrapping it
in a struct and adding a member for the length.

The sentinel will be dropped next.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20170822132255.23945-13-marcandre.lureau@redhat.com>
[Basically redone]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-16-git-send-email-armbru@redhat.com>
[Rebased]

1 files changed, 8 insertions, 5 deletions

diff --git a/scripts/qapi.py b/scripts/qapi.py
index 8736b9c786..39a67270fc 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -1849,19 +1849,22 @@ def guardend(name):
 def gen_enum_lookup(name, values, prefix=None):
     ret = mcgen('''
 
-const char *const %(c_name)s_lookup[] = {
+const QEnumLookup %(c_name)s_lookup = {
+    .array = (const char *const[]) {
 ''',
                 c_name=c_name(name))
     for value in values:
         index = c_enum_const(name, value, prefix)
         ret += mcgen('''
-    [%(index)s] = "%(value)s",
+        [%(index)s] = "%(value)s",
 ''',
                      index=index, value=value)
 
     max_index = c_enum_const(name, '_MAX', prefix)
     ret += mcgen('''
-    [%(max_index)s] = NULL,
+        [%(max_index)s] = NULL,
+    },
+    .size = %(max_index)s
 };
 ''',
                  max_index=max_index)
@@ -1895,9 +1898,9 @@ typedef enum %(c_name)s {
     ret += mcgen('''
 
 #define %(c_name)s_str(val) \\
-    qapi_enum_lookup(%(c_name)s_lookup, (val))
+    qapi_enum_lookup(&%(c_name)s_lookup, (val))
 
-extern const char *const %(c_name)s_lookup[];
+extern const QEnumLookup %(c_name)s_lookup;
 ''',
                  c_name=c_name(name))
     return ret