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>

1 files changed, 7 insertions, 7 deletions

diff --git a/hmp.c b/hmp.c
index 2140605..1b402c4 100644
--- a/hmp.c
+++ b/hmp.c
@@ -855,7 +855,7 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
                            tpo->has_cancel_path ? ",cancel-path=" : "",
                            tpo->has_cancel_path ? tpo->cancel_path : "");
             break;
-        case TPM_TYPE_OPTIONS_KIND_MAX:
+        case TPM_TYPE_OPTIONS_KIND__MAX:
             break;
         }
         monitor_printf(mon, "\n");
@@ -1203,7 +1203,7 @@ void hmp_migrate_set_capability(Monitor *mon, const QDict *qdict)
     MigrationCapabilityStatusList *caps = g_malloc0(sizeof(*caps));
     int i;
 
-    for (i = 0; i < MIGRATION_CAPABILITY_MAX; i++) {
+    for (i = 0; i < MIGRATION_CAPABILITY__MAX; i++) {
         if (strcmp(cap, MigrationCapability_lookup[i]) == 0) {
             caps->value = g_malloc0(sizeof(*caps->value));
             caps->value->capability = i;
@@ -1214,7 +1214,7 @@ void hmp_migrate_set_capability(Monitor *mon, const QDict *qdict)
         }
     }
 
-    if (i == MIGRATION_CAPABILITY_MAX) {
+    if (i == MIGRATION_CAPABILITY__MAX) {
         error_setg(&err, QERR_INVALID_PARAMETER, cap);
     }
 
@@ -1239,7 +1239,7 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
     bool has_x_cpu_throttle_increment = false;
     int i;
 
-    for (i = 0; i < MIGRATION_PARAMETER_MAX; i++) {
+    for (i = 0; i < MIGRATION_PARAMETER__MAX; i++) {
         if (strcmp(param, MigrationParameter_lookup[i]) == 0) {
             switch (i) {
             case MIGRATION_PARAMETER_COMPRESS_LEVEL:
@@ -1268,7 +1268,7 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
         }
     }
 
-    if (i == MIGRATION_PARAMETER_MAX) {
+    if (i == MIGRATION_PARAMETER__MAX) {
         error_setg(&err, QERR_INVALID_PARAMETER, param);
     }
 
@@ -1368,7 +1368,7 @@ void hmp_change(Monitor *mon, const QDict *qdict)
         if (read_only) {
             read_only_mode =
                 qapi_enum_parse(BlockdevChangeReadOnlyMode_lookup,
-                                read_only, BLOCKDEV_CHANGE_READ_ONLY_MODE_MAX,
+                                read_only, BLOCKDEV_CHANGE_READ_ONLY_MODE__MAX,
                                 BLOCKDEV_CHANGE_READ_ONLY_MODE_RETAIN, &err);
             if (err) {
                 hmp_handle_error(mon, &err);
@@ -1771,7 +1771,7 @@ void hmp_sendkey(Monitor *mon, const QDict *qdict)
             keylist->value->u.number = value;
         } else {
             int idx = index_from_key(keyname_buf);
-            if (idx == Q_KEY_CODE_MAX) {
+            if (idx == Q_KEY_CODE__MAX) {
                 goto err_out;
             }
             keylist->value->type = KEY_VALUE_KIND_QCODE;