qapi: Avoid unnecessary use of enum lookup table's sentinel

Currently, the FOO_lookup[] generated for QAPI enum types are
terminated by a NULL sentinel.

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

To prepare for that, replace "have we reached the sentinel?"
predicates by "have we reached the FOO__MAX value?" predicates.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-12-git-send-email-armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>

monitor.c

@@ -3249,7 +3249,7 @@ void netdev_add_completion(ReadLineState *rs, int nb_args, const char *str)
     }
     len = strlen(str);
     readline_set_completion_index(rs, len);
-    for (i = 0; NetClientDriver_lookup[i]; i++) {
+    for (i = 0; i < NET_CLIENT_DRIVER__MAX; i++) {
         add_completion_option(rs, str, NetClientDriver_lookup[i]);
     }
 }
@@ -3537,7 +3537,7 @@ void watchdog_action_completion(ReadLineState *rs, int nb_args, const char *str)
         return;
     }
     readline_set_completion_index(rs, strlen(str));
-    for (i = 0; WatchdogExpirationAction_lookup[i]; i++) {
+    for (i = 0; i < WATCHDOG_EXPIRATION_ACTION__MAX; i++) {
         add_completion_option(rs, str, WatchdogExpirationAction_lookup[i]);
     }
 }

tests/test-qobject-input-visitor.c

@@ -382,7 +382,7 @@ static void test_visitor_in_enum(TestInputVisitorData *data,
     Visitor *v;
     EnumOne i;
 
-    for (i = 0; EnumOne_lookup[i]; i++) {
+    for (i = 0; i < ENUM_ONE__MAX; i++) {
         EnumOne res = -1;
 
         v = visitor_input_test_init(data, "%s", EnumOne_lookup[i]);

tests/test-string-input-visitor.c

@@ -279,7 +279,7 @@ static void test_visitor_in_enum(TestInputVisitorData *data,
     Visitor *v;
     EnumOne i;
 
-    for (i = 0; EnumOne_lookup[i]; i++) {
+    for (i = 0; i < ENUM_ONE__MAX; i++) {
         EnumOne res = -1;
 
         v = visitor_input_test_init(data, EnumOne_lookup[i]);

ui/input-legacy.c

@@ -61,7 +61,7 @@ int index_from_key(const char *key, size_t key_length)
 {
     int i;
 
-    for (i = 0; QKeyCode_lookup[i] != NULL; i++) {
+    for (i = 0; i < Q_KEY_CODE__MAX; i++) {
         if (!strncmp(key, QKeyCode_lookup[i], key_length) &&
             !QKeyCode_lookup[i][key_length]) {
             break;