qapi: Don't let implicit enum MAX member collide

Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes.  Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.

This patch was mostly generated by applying a temporary patch:

|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
|     max_index = c_enum_const(name, 'MAX', prefix)
|     ret += mcgen('''
|     [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
|                max_index=max_index)

then running:

$ cat qapi-{types,event}.c tests/test-qapi-types.c |
    sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list

The only things not generated are the changes in scripts/qapi.py.

Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1447836791-369-23-git-send-email-eblake@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Rebased to current master, commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>

2 files changed, 5 insertions, 5 deletions

diff --git a/tests/test-qmp-output-visitor.c b/tests/test-qmp-output-visitor.c
index 0d0c85989a..4196e66dde 100644
--- a/tests/test-qmp-output-visitor.c
+++ b/tests/test-qmp-output-visitor.c
@@ -128,7 +128,7 @@ static void test_visitor_out_enum(TestOutputVisitorData *data,
     QObject *obj;
     EnumOne i;
 
-    for (i = 0; i < ENUM_ONE_MAX; i++) {
+    for (i = 0; i < ENUM_ONE__MAX; i++) {
         visit_type_EnumOne(data->ov, &i, "unused", &error_abort);
 
         obj = qmp_output_get_qobject(data->qov);
@@ -143,7 +143,7 @@ static void test_visitor_out_enum(TestOutputVisitorData *data,
 static void test_visitor_out_enum_errors(TestOutputVisitorData *data,
                                          const void *unused)
 {
-    EnumOne i, bad_values[] = { ENUM_ONE_MAX, -1 };
+    EnumOne i, bad_values[] = { ENUM_ONE__MAX, -1 };
     Error *err;
 
     for (i = 0; i < ARRAY_SIZE(bad_values) ; i++) {
@@ -247,7 +247,7 @@ static void test_visitor_out_struct_nested(TestOutputVisitorData *data,
 static void test_visitor_out_struct_errors(TestOutputVisitorData *data,
                                            const void *unused)
 {
-    EnumOne bad_values[] = { ENUM_ONE_MAX, -1 };
+    EnumOne bad_values[] = { ENUM_ONE__MAX, -1 };
     UserDefOne u = {0};
     UserDefOne *pu = &u;
     Error *err;
diff --git a/tests/test-string-output-visitor.c b/tests/test-string-output-visitor.c
index fd5e67be64..95852523b4 100644
--- a/tests/test-string-output-visitor.c
+++ b/tests/test-string-output-visitor.c
@@ -194,7 +194,7 @@ static void test_visitor_out_enum(TestOutputVisitorData *data,
     char *str;
     EnumOne i;
 
-    for (i = 0; i < ENUM_ONE_MAX; i++) {
+    for (i = 0; i < ENUM_ONE__MAX; i++) {
         char *str_human;
 
         visit_type_EnumOne(data->ov, &i, "unused", &err);
@@ -217,7 +217,7 @@ static void test_visitor_out_enum(TestOutputVisitorData *data,
 static void test_visitor_out_enum_errors(TestOutputVisitorData *data,
                                          const void *unused)
 {
-    EnumOne i, bad_values[] = { ENUM_ONE_MAX, -1 };
+    EnumOne i, bad_values[] = { ENUM_ONE__MAX, -1 };
     Error *err;
 
     for (i = 0; i < ARRAY_SIZE(bad_values) ; i++) {