From 5191a44547cf406463e0d22206c659a6c0c0391b Mon Sep 17 00:00:00 2001
From: Christian Dywan <christian.dywan@lanedo.com>
Date: Thu, 23 Sep 2010 19:22:53 +0200
Subject: [PATCH] Implement dbus_message_iter_get_n_elements

See https://bugs.freedesktop.org/show_bug.cgi?id=30350
---
 dbus/dbus-message-util.c |   20 ++++++++++++++++++++
 dbus/dbus-message.c      |   34 +++++++++++++++++++++++++++-------
 dbus/dbus-message.h      |    3 +++
 3 files changed, 50 insertions(+), 7 deletions(-)

diff --git a/dbus/dbus-message-util.c b/dbus/dbus-message-util.c
index f972c8a..9fcddb6 100644
--- a/dbus/dbus-message-util.c
+++ b/dbus/dbus-message-util.c
@@ -1396,6 +1396,26 @@ _dbus_message_test (const char *test_data_dir)
   check_memleaks ();
   _dbus_check_fdleaks();
 
+  /* Test enumeration of array elements */
+  message = dbus_message_new_method_call ("de.ende.test",
+                                          "/de/ende/test",
+                                          "de.ende.Test",
+                                          "ArtistName");
+  _dbus_assert (message != NULL);
+  dbus_message_iter_init_append (message, &iter);
+  dbus_message_iter_open_container (&iter, DBUS_TYPE_ARRAY,
+                                    DBUS_TYPE_STRING_AS_STRING, &array_iter);
+  s = "SomeThingToSay";
+  dbus_message_iter_append_basic (&array_iter, DBUS_TYPE_STRING, &s);
+  s = "MoreHumbugToCome";
+  dbus_message_iter_append_basic (&array_iter, DBUS_TYPE_STRING, &s);
+  s = "WerewolvesMinotaursKirins";
+  dbus_message_iter_append_basic (&array_iter, DBUS_TYPE_STRING, &s);
+  dbus_message_iter_close_container (&iter, &array_iter);
+  dbus_message_iter_init (message, &iter);
+  _dbus_assert (dbus_message_iter_get_n_elements (&iter) == 3);
+  dbus_message_unref (message);
+
   /* Check that we can abandon a container */
   message = dbus_message_new_method_call ("org.freedesktop.DBus.TestService",
 		  			  "/org/freedesktop/TestPath",
diff --git a/dbus/dbus-message.c b/dbus/dbus-message.c
index b19697e..c0e4247 100644
--- a/dbus/dbus-message.c
+++ b/dbus/dbus-message.c
@@ -2177,20 +2177,40 @@ dbus_message_iter_get_basic (DBusMessageIter  *iter,
 }
 
 /**
+ * Returns the number of elements in the array-typed value pointed
+ * to by the iterator.
+ *
+ * @param iter the iterator
+ * @returns the number of elements in the array
+ */
+int dbus_message_iter_get_n_elements (DBusMessageIter* iter)
+{
+  DBusMessageRealIter *real = (DBusMessageRealIter *)iter;
+  DBusTypeReader array;
+  int n_elements = 0;
+
+  _dbus_return_val_if_fail (_dbus_message_iter_check (real), 0);
+  _dbus_return_val_if_fail (_dbus_type_reader_get_current_type (&real->u.reader)
+                            == DBUS_TYPE_ARRAY, 0);
+
+  _dbus_type_reader_recurse (&real->u.reader, &array);
+  while (_dbus_type_reader_get_current_type (&array) != DBUS_TYPE_INVALID)
+    {
+      ++n_elements;
+      _dbus_type_reader_next (&array);
+    }
+  return n_elements;
+}
+
+/**
  * Returns the number of bytes in the array as marshaled in the wire
  * protocol. The iterator must currently be inside an array-typed
  * value.
  *
  * This function is deprecated on the grounds that it is stupid.  Why
  * would you want to know how many bytes are in the array as marshaled
- * in the wire protocol?  For now, use the n_elements returned from
- * dbus_message_iter_get_fixed_array() instead, or iterate over the
- * array values and count them.
+ * in the wire protocol?  Use dbus_message_iter_get_n_elements() instead.
  *
- * @todo introduce a variant of this get_n_elements that returns
- * the number of elements, though with a non-fixed array it will not
- * be very efficient, so maybe it's not good.
- * 
  * @param iter the iterator
  * @returns the number of bytes in the array
  */
diff --git a/dbus/dbus-message.h b/dbus/dbus-message.h
index 5500492..2543c7c 100644
--- a/dbus/dbus-message.h
+++ b/dbus/dbus-message.h
@@ -226,6 +226,9 @@ void        dbus_message_iter_recurse          (DBusMessageIter *iter,
 DBUS_EXPORT
 void        dbus_message_iter_get_basic        (DBusMessageIter *iter,
                                                 void            *value);
+DBUS_EXPORT
+int         dbus_message_iter_get_n_elements   (DBusMessageIter *iter);
+
 #ifndef DBUS_DISABLE_DEPRECATED
 /* This function returns the wire protocol size of the array in bytes,
  * you do not want to know that probably
-- 
1.7.2.3