QemuOpts: Drop qemu_opts_foreach() parameter abort_on_failure

When the argument is non-zero, qemu_opts_foreach() stops on callback
returning non-zero, and returns that value.

When the argument is zero, it doesn't stop, and returns the bit-wise
inclusive or of all the return values.  Funky :)

The callers that pass zero could just as well pass one, because their
callbacks can't return anything but zero:

* qemu_add_globals()'s callback qdev_add_one_global()

* qemu_config_write()'s callback config_write_opts()

* main()'s callbacks default_driver_check(), drive_enable_snapshot(),
  vnc_init_func()

Drop the parameter, and always stop.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Kevin Wolf <kwolf@redhat.com>

2 files changed, 15 insertions, 8 deletions

diff --git a/util/qemu-config.c b/util/qemu-config.c
index 30d6dcf526..b38927a88d 100644
--- a/util/qemu-config.c
+++ b/util/qemu-config.c
@@ -367,7 +367,7 @@ void qemu_config_write(FILE *fp)
     fprintf(fp, "# qemu config file\n\n");
     for (i = 0; lists[i] != NULL; i++) {
         data.list = lists[i];
-        qemu_opts_foreach(data.list, config_write_opts, &data, 0);
+        qemu_opts_foreach(data.list, config_write_opts, &data);
     }
 }
 
diff --git a/util/qemu-option.c b/util/qemu-option.c
index fda4e5fcbf..7672aae897 100644
--- a/util/qemu-option.c
+++ b/util/qemu-option.c
@@ -1046,22 +1046,29 @@ void qemu_opts_validate(QemuOpts *opts, const QemuOptDesc *desc, Error **errp)
     }
 }
 
-int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func, void *opaque,
-                      int abort_on_failure)
+/**
+ * For each member of @list, call @func(member, @opaque).
+ * Call it with the current location temporarily set to the member's.
+ * When @func() returns non-zero, break the loop and return that value.
+ * Return zero when the loop completes.
+ */
+int qemu_opts_foreach(QemuOptsList *list, qemu_opts_loopfunc func,
+                      void *opaque)
 {
     Location loc;
     QemuOpts *opts;
-    int rc = 0;
+    int rc;
 
     loc_push_none(&loc);
     QTAILQ_FOREACH(opts, &list->head, next) {
         loc_restore(&opts->loc);
-        rc |= func(opts, opaque);
-        if (abort_on_failure  &&  rc != 0)
-            break;
+        rc = func(opts, opaque);
+        if (rc) {
+            return rc;
+        }
     }
     loc_pop(&loc);
-    return rc;
+    return 0;
 }
 
 static size_t count_opts_list(QemuOptsList *list)