Add TAILQ_FOREACH_SAFE (Jan Kiszka)

Add TAILQ iterator that allows to safely remove elements while walking
the list.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5798 c046a42c-6fe2-441c-8c8c-71466251a162

sys-queue.h

@@ -210,6 +210,11 @@ struct {                                                                \
                 (var);                                                  \
                 (var) = ((var)->field.tqe_next))
 
+#define TAILQ_FOREACH_SAFE(var, head, field, next_var)                  \
+        for ((var) = ((head)->tqh_first);                               \
+                (var) && ((next_var) = ((var)->field.tqe_next), 1);     \
+                (var) = (next_var))
+
 #define TAILQ_FOREACH_REVERSE(var, head, headname, field)               \
         for ((var) = (*(((struct headname *)((head)->tqh_last))->tqh_last));    \
                 (var);                                                  \