libctf: add new dynhash functions

Future commits will use these.

ctf_dynhash_elements: count elements in a dynhash
ctf_dynhash_lookup_kv: look up and return pointers to the original key
                       and value in a dynhash (the only way of getting
                       a reference to the original key)
ctf_dynhash_iter_find: iterate until an item is found, then return its
                       key
ctf_dynhash_cinsert: insert a const key / value into a dynhash (a thim
                     wrapper in a new header dedicated to inline
                     functions).

As with the rest of ctf_dynhash, this is not public API.  No impact
on existing callers is expected.

libctf/
	* ctf-inlines.h: New file.
	* ctf-impl.h: Include it.
	(ctf_hash_iter_find_f): New typedef.
	(ctf_dynhash_elements): New.
	(ctf_dynhash_lookup_kv): New.
	(ctf_dynhash_iter_find): New.
	* ctf-hash.c (ctf_dynhash_lookup_kv): New.
	(ctf_traverse_find_cb_arg_t): New.
	(ctf_hashtab_traverse_find): New.
	(ctf_dynhash_iter_find): New.
	(ctf_dynhash_elements): New.

libctf/ctf-hash.c

@@ -218,6 +218,12 @@ ctf_dynhash_empty (ctf_dynhash_t *hp)
   htab_empty (hp->htab);
 }
 
+size_t
+ctf_dynhash_elements (ctf_dynhash_t *hp)
+{
+  return htab_elements (hp->htab);
+}
+
 void *
 ctf_dynhash_lookup (ctf_dynhash_t *hp, const void *key)
 {
@@ -231,6 +237,26 @@ ctf_dynhash_lookup (ctf_dynhash_t *hp, const void *key)
   return NULL;
 }
 
+/* TRUE/FALSE return.  */
+int
+ctf_dynhash_lookup_kv (ctf_dynhash_t *hp, const void *key,
+		       const void **orig_key, void **value)
+{
+  ctf_helem_t **slot;
+
+  slot = ctf_hashtab_lookup (hp->htab, key, NO_INSERT);
+
+  if (slot)
+    {
+      if (orig_key)
+	*orig_key = (*slot)->key;
+      if (value)
+	*value = (*slot)->value;
+      return 1;
+    }
+  return 0;
+}
+
 typedef struct ctf_traverse_cb_arg
 {
   ctf_hash_iter_f fun;
@@ -254,6 +280,35 @@ ctf_dynhash_iter (ctf_dynhash_t *hp, ctf_hash_iter_f fun, void *arg_)
   htab_traverse (hp->htab, ctf_hashtab_traverse, &arg);
 }
 
+typedef struct ctf_traverse_find_cb_arg
+{
+  ctf_hash_iter_find_f fun;
+  void *arg;
+  void *found_key;
+} ctf_traverse_find_cb_arg_t;
+
+static int
+ctf_hashtab_traverse_find (void **slot, void *arg_)
+{
+  ctf_helem_t *helem = *((ctf_helem_t **) slot);
+  ctf_traverse_find_cb_arg_t *arg = (ctf_traverse_find_cb_arg_t *) arg_;
+
+  if (arg->fun (helem->key, helem->value, arg->arg))
+    {
+      arg->found_key = helem->key;
+      return 0;
+    }
+  return 1;
+}
+
+void *
+ctf_dynhash_iter_find (ctf_dynhash_t *hp, ctf_hash_iter_find_f fun, void *arg_)
+{
+  ctf_traverse_find_cb_arg_t arg = { fun, arg_, NULL };
+  htab_traverse (hp->htab, ctf_hashtab_traverse_find, &arg);
+  return arg.found_key;
+}
+
 typedef struct ctf_traverse_remove_cb_arg
 {
   struct htab *htab;