cirrus: Use FreeBSD 12.2.

[mirror_ovs.git] / lib / cmap.h

diff --git a/lib/cmap.h b/lib/cmap.h
index 5a72b65bec5efcad0c6158dca2de50db42b13922..d9db3c915cbfab48e98e3f033e1200a8855260a8 100644 (file)
--- a/lib/cmap.h
+++ b/lib/cmap.h
@@ -145,6 +145,17 @@ size_t cmap_replace(struct cmap *, struct cmap_node *old_node,
 const struct cmap_node *cmap_find(const struct cmap *, uint32_t hash);
 struct cmap_node *cmap_find_protected(const struct cmap *, uint32_t hash);
 
+/* Find node by index or find index by hash. The 'index' of a cmap entry is a
+ * way to combine the specific bucket and the entry of the bucket into a
+ * convenient single integer value. In other words, it is the index of the
+ * entry and each entry has an unique index. It is not used internally by
+ * cmap.
+ * Currently the functions assume index will not be larger than uint32_t. In
+ * OvS table size is usually much smaller than this size.*/
+const struct cmap_node * cmap_find_by_index(const struct cmap *,
+                                            uint32_t index);
+uint32_t cmap_find_index(const struct cmap *, uint32_t hash);
+
 /* Looks up multiple 'hashes', when the corresponding bit in 'map' is 1,
  * and sets the corresponding pointer in 'nodes', if the hash value was
  * found from the 'cmap'.  In other cases the 'nodes' values are not changed,
@@ -189,13 +200,12 @@ unsigned long cmap_find_batch(const struct cmap *cmap, unsigned long map,
  *         int extra_data;
  *     };
  *
- *     struct cmap_cursor cursor;
- *     struct my_node *iter;
  *     struct cmap my_map;
+ *     struct my_node *my_node;
  *
- *     cmap_init(&cmap);
+ *     cmap_init(&my_map);
  *     ...add data...
- *     CMAP_FOR_EACH (my_node, cmap_node, &cursor, &cmap) {
+ *     CMAP_FOR_EACH (my_node, cmap_node, &my_map) {
  *         ...operate on my_node...
  *     }
  *
@@ -233,11 +243,20 @@ struct cmap_cursor {
 struct cmap_cursor cmap_cursor_start(const struct cmap *);
 void cmap_cursor_advance(struct cmap_cursor *);
 
-#define CMAP_FOR_EACH(NODE, MEMBER, CMAP)                       \
-    for (struct cmap_cursor cursor__ = cmap_cursor_start(CMAP); \
-         CMAP_CURSOR_FOR_EACH__(NODE, &cursor__, MEMBER);       \
+/* Generate a unique name for the cursor with the __COUNTER__ macro to
+ * allow nesting of CMAP_FOR_EACH loops. */
+#define CURSOR_JOIN2(x,y) x##y
+#define CURSOR_JOIN(x, y) CURSOR_JOIN2(x,y)
+
+#define CMAP_FOR_EACH__(NODE, MEMBER, CMAP, CURSOR_NAME)           \
+    for (struct cmap_cursor CURSOR_NAME = cmap_cursor_start(CMAP); \
+         CMAP_CURSOR_FOR_EACH__(NODE, &CURSOR_NAME, MEMBER);       \
         )
 
+#define CMAP_FOR_EACH(NODE, MEMBER, CMAP) \
+          CMAP_FOR_EACH__(NODE, MEMBER, CMAP, \
+                CURSOR_JOIN(cursor_, __COUNTER__))
+
 static inline struct cmap_node *cmap_first(const struct cmap *);
 
 /* Another, less preferred, form of iteration, for use in situations where it