commit 7fb1cf1606c78c9d5b538f29176fd5a101726a9d
author Eric Blake <eblake@redhat.com> Wed Nov 18 01:52:57 2015 -0700
committer Markus Armbruster <armbru@redhat.com> Thu Dec 17 08:21:28 2015 +0100
tree 69733bce4ee4a3c1ecd04f5b9a5f65ef1c50e106
parent 59a92feedc6927e0e1ff87fdaccfb4dd42ad4c84

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>

block/blkdebug.c

diff --git a/block/blkdebug.c b/block/blkdebug.c
index 6bcb7fa..59c61eb 100644
--- a/block/blkdebug.c
+++ b/block/blkdebug.c
@@ -36,7 +36,7 @@
     int state;
     int new_state;
 
-    QLIST_HEAD(, BlkdebugRule) rules[BLKDBG_MAX];
+    QLIST_HEAD(, BlkdebugRule) rules[BLKDBG__MAX];
     QSIMPLEQ_HEAD(, BlkdebugRule) active_rules;
     QLIST_HEAD(, BlkdebugSuspendedReq) suspended_reqs;
 } BDRVBlkdebugState;
@@ -147,7 +147,7 @@
 {
     int i;
 
-    for (i = 0; i < BLKDBG_MAX; i++) {
+    for (i = 0; i < BLKDBG__MAX; i++) {
         if (!strcmp(BlkdebugEvent_lookup[i], name)) {
             *event = i;
             return 0;
@@ -507,7 +507,7 @@
     BlkdebugRule *rule, *next;
     int i;
 
-    for (i = 0; i < BLKDBG_MAX; i++) {
+    for (i = 0; i < BLKDBG__MAX; i++) {
         QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) {
             remove_rule(rule);
         }
@@ -576,7 +576,7 @@
     struct BlkdebugRule *rule, *next;
     bool injected;
 
-    assert((int)event >= 0 && event < BLKDBG_MAX);
+    assert((int)event >= 0 && event < BLKDBG__MAX);
 
     injected = false;
     s->new_state = s->state;
@@ -633,7 +633,7 @@
     BlkdebugRule *rule, *next;
     int i, ret = -ENOENT;
 
-    for (i = 0; i < BLKDBG_MAX; i++) {
+    for (i = 0; i < BLKDBG__MAX; i++) {
         QLIST_FOREACH_SAFE(rule, &s->rules[i], next, next) {
             if (rule->action == ACTION_SUSPEND &&
                 !strcmp(rule->options.suspend.tag, tag)) {