[daemon-fix] fixed querying about name information
[platform/upstream/dbus.git] / dbus / dbus-pending-call.c
index e0d8e3e..be53410 100644 (file)
@@ -1,9 +1,9 @@
-/* -*- mode: C; c-file-style: "gnu" -*- */
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
 /* dbus-pending-call.c Object representing a call in progress.
  *
  * Copyright (C) 2002, 2003 Red Hat Inc.
  *
- * Licensed under the Academic Free License version 1.2
+ * Licensed under the Academic Free License version 2.1
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  *
  */
 
+#include <config.h>
 #include "dbus-internals.h"
 #include "dbus-connection-internal.h"
+#include "dbus-message-internal.h"
+#include "dbus-pending-call-internal.h"
 #include "dbus-pending-call.h"
 #include "dbus-list.h"
 #include "dbus-threads.h"
  * @{
  */
 
+/**
+ * @brief Internals of DBusPendingCall
+ *
+ * Opaque object representing a reply message that we're waiting for.
+ */
+
+/**
+ * shorter and more visible way to write _dbus_connection_lock()
+ */
+#define CONNECTION_LOCK(connection)   _dbus_connection_lock(connection)
+/**
+ * shorter and more visible way to write _dbus_connection_unlock()
+ */
+#define CONNECTION_UNLOCK(connection) _dbus_connection_unlock(connection)
+
+/**
+ * Implementation details of #DBusPendingCall - all fields are private.
+ */
+struct DBusPendingCall
+{
+  DBusAtomic refcount;                            /**< reference count */
+
+  DBusDataSlotList slot_list;                     /**< Data stored by allocated integer ID */
+  
+  DBusPendingCallNotifyFunction function;         /**< Notifier when reply arrives. */
+
+  DBusConnection *connection;                     /**< Connections we're associated with */
+  DBusMessage *reply;                             /**< Reply (after we've received it) */
+  DBusTimeout *timeout;                           /**< Timeout */
+
+  DBusList *timeout_link;                         /**< Preallocated timeout response */
+  
+  dbus_uint32_t reply_serial;                     /**< Expected serial of reply */
+
+  unsigned int completed : 1;                     /**< TRUE if completed */
+  unsigned int timeout_added : 1;                 /**< Have added the timeout */
+};
+
+static void
+_dbus_pending_call_trace_ref (DBusPendingCall *pending_call,
+    int old_refcount,
+    int new_refcount,
+    const char *why)
+{
+#ifdef DBUS_ENABLE_VERBOSE_MODE
+  static int enabled = -1;
+
+  _dbus_trace_ref ("DBusPendingCall", pending_call, old_refcount,
+      new_refcount, why, "DBUS_PENDING_CALL_TRACE", &enabled);
+#endif
+}
+
 static dbus_int32_t notify_user_data_slot = -1;
 
 /**
  * Creates a new pending reply object.
  *
  * @param connection connection where reply will arrive
- * @param timeout_milliseconds length of timeout, -1 for default
+ * @param timeout_milliseconds length of timeout, -1 (or
+ *  #DBUS_TIMEOUT_USE_DEFAULT) for default,
+ *  #DBUS_TIMEOUT_INFINITE for no timeout
  * @param timeout_handler timeout handler, takes pending call as data
  * @returns a new #DBusPendingCall or #NULL if no memory.
  */
 DBusPendingCall*
-_dbus_pending_call_new (DBusConnection    *connection,
-                        int                timeout_milliseconds,
-                        DBusTimeoutHandler timeout_handler)
+_dbus_pending_call_new_unlocked (DBusConnection    *connection,
+                                 int                timeout_milliseconds,
+                                 DBusTimeoutHandler timeout_handler)
 {
   DBusPendingCall *pending;
   DBusTimeout *timeout;
 
-  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);
-  
+  _dbus_assert (timeout_milliseconds >= 0 || timeout_milliseconds == -1);
   if (timeout_milliseconds == -1)
     timeout_milliseconds = _DBUS_DEFAULT_TIMEOUT_VALUE;
 
@@ -72,27 +129,71 @@ _dbus_pending_call_new (DBusConnection    *connection,
       return NULL;
     }
 
-  timeout = _dbus_timeout_new (timeout_milliseconds,
-                               timeout_handler,
-                              pending, NULL);  
+  if (timeout_milliseconds != DBUS_TIMEOUT_INFINITE)
+    {
+      timeout = _dbus_timeout_new (timeout_milliseconds,
+                                   timeout_handler,
+                                   pending, NULL);  
 
-  if (timeout == NULL)
+      if (timeout == NULL)
+        {
+          dbus_pending_call_free_data_slot (&notify_user_data_slot);
+          dbus_free (pending);
+          return NULL;
+        }
+
+      pending->timeout = timeout;
+    }
+  else
     {
-      dbus_pending_call_free_data_slot (&notify_user_data_slot);
-      dbus_free (pending);
-      return NULL;
+      pending->timeout = NULL;
     }
-  
-  pending->refcount.value = 1;
+
+  _dbus_atomic_inc (&pending->refcount);
   pending->connection = connection;
-  pending->timeout = timeout;
+  _dbus_connection_ref_unlocked (pending->connection);
 
   _dbus_data_slot_list_init (&pending->slot_list);
-  
+
+  _dbus_pending_call_trace_ref (pending, 0, 1, "new_unlocked");
+
   return pending;
 }
 
 /**
+ * Sets the reply of a pending call with the given message,
+ * or if the message is #NULL, by timing out the pending call.
+ * 
+ * @param pending the pending call
+ * @param message the message to complete the call with, or #NULL
+ *  to time out the call
+ */
+void
+_dbus_pending_call_set_reply_unlocked (DBusPendingCall *pending,
+                                       DBusMessage     *message)
+{
+  if (message == NULL)
+    {
+      message = pending->timeout_link->data;
+      _dbus_list_clear (&pending->timeout_link);
+    }
+  else
+    dbus_message_ref (message);
+
+  _dbus_verbose ("  handing message %p (%s) to pending call serial %u\n",
+                 message,
+                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_METHOD_RETURN ?
+                 "method return" :
+                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_ERROR ?
+                 "error" : "other type",
+                 pending->reply_serial);
+  
+  _dbus_assert (pending->reply == NULL);
+  _dbus_assert (pending->reply_serial == dbus_message_get_reply_serial (message));
+  pending->reply = message;
+}
+
+/**
  * Calls notifier function for the pending call
  * and sets the call to completed.
  *
@@ -100,8 +201,10 @@ _dbus_pending_call_new (DBusConnection    *connection,
  * 
  */
 void
-_dbus_pending_call_notify (DBusPendingCall *pending)
+_dbus_pending_call_complete (DBusPendingCall *pending)
 {
+  _dbus_assert (!pending->completed);
+  
   pending->completed = TRUE;
 
   if (pending->function)
@@ -114,6 +217,316 @@ _dbus_pending_call_notify (DBusPendingCall *pending)
     }
 }
 
+/**
+ * If the pending call hasn't been timed out, add its timeout
+ * error reply to the connection's incoming message queue.
+ *
+ * @param pending the pending call
+ * @param connection the connection the call was sent to
+ */
+void
+_dbus_pending_call_queue_timeout_error_unlocked (DBusPendingCall *pending, 
+                                                 DBusConnection  *connection)
+{
+  _dbus_assert (connection == pending->connection);
+  
+  if (pending->timeout_link)
+    {
+      _dbus_connection_queue_synthesized_message_link (connection,
+                                                      pending->timeout_link);
+      pending->timeout_link = NULL;
+    }
+}
+
+/**
+ * Checks to see if a timeout has been added
+ *
+ * @param pending the pending_call
+ * @returns #TRUE if there is a timeout or #FALSE if not
+ */
+dbus_bool_t 
+_dbus_pending_call_is_timeout_added_unlocked (DBusPendingCall  *pending)
+{
+  _dbus_assert (pending != NULL);
+
+  return pending->timeout_added;
+}
+
+
+/**
+ * Sets wether the timeout has been added
+ *
+ * @param pending the pending_call
+ * @param is_added whether or not a timeout is added
+ */
+void
+_dbus_pending_call_set_timeout_added_unlocked (DBusPendingCall  *pending,
+                                               dbus_bool_t       is_added)
+{
+  _dbus_assert (pending != NULL);
+
+  pending->timeout_added = is_added;
+}
+
+
+/**
+ * Retrives the timeout
+ *
+ * @param pending the pending_call
+ * @returns a timeout object or NULL if call has no timeout
+ */
+DBusTimeout *
+_dbus_pending_call_get_timeout_unlocked (DBusPendingCall  *pending)
+{
+  _dbus_assert (pending != NULL);
+
+  return pending->timeout;
+}
+
+/**
+ * Gets the reply's serial number
+ *
+ * @param pending the pending_call
+ * @returns a serial number for the reply or 0 
+ */
+dbus_uint32_t 
+_dbus_pending_call_get_reply_serial_unlocked (DBusPendingCall  *pending)
+{
+  _dbus_assert (pending != NULL);
+
+  return pending->reply_serial;
+}
+
+/**
+ * Sets the reply's serial number
+ *
+ * @param pending the pending_call
+ * @param serial the serial number 
+ */
+void
+_dbus_pending_call_set_reply_serial_unlocked  (DBusPendingCall *pending,
+                                               dbus_uint32_t serial)
+{
+  _dbus_assert (pending != NULL);
+  _dbus_assert (pending->reply_serial == 0);
+
+  pending->reply_serial = serial;
+}
+
+/**
+ * Gets the connection associated with this pending call.
+ *
+ * @param pending the pending_call
+ * @returns the connection associated with the pending call
+ */
+DBusConnection *
+_dbus_pending_call_get_connection_and_lock (DBusPendingCall *pending)
+{
+  _dbus_assert (pending != NULL);
+  CONNECTION_LOCK (pending->connection);
+  return pending->connection;
+}
+
+/**
+ * Gets the connection associated with this pending call.
+ *
+ * @param pending the pending_call
+ * @returns the connection associated with the pending call
+ */
+DBusConnection *
+_dbus_pending_call_get_connection_unlocked (DBusPendingCall *pending)
+{
+  _dbus_assert (pending != NULL);
+  return pending->connection;
+}
+
+/**
+ * Sets the reply message associated with the pending call to a timeout error
+ *
+ * @param pending the pending_call
+ * @param message the message we are sending the error reply to 
+ * @param serial serial number for the reply
+ * @return #FALSE on OOM
+ */
+dbus_bool_t
+_dbus_pending_call_set_timeout_error_unlocked (DBusPendingCall *pending,
+                                               DBusMessage     *message,
+                                               dbus_uint32_t    serial)
+{ 
+  DBusList *reply_link;
+  DBusMessage *reply;
+
+  reply = dbus_message_new_error (message, DBUS_ERROR_NO_REPLY,
+                                  "Did not receive a reply. Possible causes include: "
+                                  "the remote application did not send a reply, "
+                                  "the message bus security policy blocked the reply, "
+                                  "the reply timeout expired, or "
+                                  "the network connection was broken.");
+  if (reply == NULL)
+    return FALSE;
+
+  reply_link = _dbus_list_alloc_link (reply);
+  if (reply_link == NULL)
+    {
+      /* it's OK to unref this, nothing that could have attached a callback
+       * has ever seen it */
+      dbus_message_unref (reply);
+      return FALSE;
+    }
+
+  pending->timeout_link = reply_link;
+
+  _dbus_pending_call_set_reply_serial_unlocked (pending, serial);
+  
+  return TRUE;
+}
+
+/**
+ * Increments the reference count on a pending call,
+ * while the lock on its connection is already held.
+ *
+ * @param pending the pending call object
+ * @returns the pending call object
+ */
+DBusPendingCall *
+_dbus_pending_call_ref_unlocked (DBusPendingCall *pending)
+{
+  dbus_int32_t old_refcount;
+
+  old_refcount = _dbus_atomic_inc (&pending->refcount);
+  _dbus_pending_call_trace_ref (pending, old_refcount, old_refcount + 1,
+      "ref_unlocked");
+
+  return pending;
+}
+
+
+static void
+_dbus_pending_call_last_unref (DBusPendingCall *pending)
+{
+  DBusConnection *connection;
+  
+  /* If we get here, we should be already detached
+   * from the connection, or never attached.
+   */
+  _dbus_assert (!pending->timeout_added);  
+
+  connection = pending->connection;
+
+  /* this assumes we aren't holding connection lock... */
+  _dbus_data_slot_list_free (&pending->slot_list);
+
+  if (pending->timeout != NULL)
+    _dbus_timeout_unref (pending->timeout);
+      
+  if (pending->timeout_link)
+    {
+      dbus_message_unref ((DBusMessage *)pending->timeout_link->data);
+      _dbus_list_free_link (pending->timeout_link);
+      pending->timeout_link = NULL;
+    }
+
+  if (pending->reply)
+    {
+      dbus_message_unref (pending->reply);
+      pending->reply = NULL;
+    }
+      
+  dbus_free (pending);
+
+  dbus_pending_call_free_data_slot (&notify_user_data_slot);
+
+  /* connection lock should not be held. */
+  /* Free the connection last to avoid a weird state while
+   * calling out to application code where the pending exists
+   * but not the connection.
+   */
+  dbus_connection_unref (connection);
+}
+
+/**
+ * Decrements the reference count on a pending call,
+ * freeing it if the count reaches 0. Assumes
+ * connection lock is already held.
+ *
+ * @param pending the pending call object
+ */
+void
+_dbus_pending_call_unref_and_unlock (DBusPendingCall *pending)
+{
+  dbus_int32_t old_refcount;
+
+  old_refcount = _dbus_atomic_dec (&pending->refcount);
+  _dbus_assert (old_refcount > 0);
+  _dbus_pending_call_trace_ref (pending, old_refcount,
+      old_refcount - 1, "unref_and_unlock");
+
+  CONNECTION_UNLOCK (pending->connection);
+
+  if (old_refcount == 1)
+    _dbus_pending_call_last_unref (pending);
+}
+
+/**
+ * Checks whether the pending call has received a reply
+ * yet, or not. Assumes connection lock is held.
+ *
+ * @param pending the pending call
+ * @returns #TRUE if a reply has been received
+ */
+dbus_bool_t
+_dbus_pending_call_get_completed_unlocked (DBusPendingCall    *pending)
+{
+  return pending->completed;
+}
+
+static DBusDataSlotAllocator slot_allocator =
+  _DBUS_DATA_SLOT_ALLOCATOR_INIT (_DBUS_LOCK_NAME (pending_call_slots));
+
+/**
+ * Stores a pointer on a #DBusPendingCall, along
+ * with an optional function to be used for freeing
+ * the data when the data is set again, or when
+ * the pending call is finalized. The slot number
+ * must have been allocated with dbus_pending_call_allocate_data_slot().
+ *
+ * @param pending the pending_call
+ * @param slot the slot number
+ * @param data the data to store
+ * @param free_data_func finalizer function for the data
+ * @returns #TRUE if there was enough memory to store the data
+ */
+dbus_bool_t
+_dbus_pending_call_set_data_unlocked (DBusPendingCall  *pending,
+                                     dbus_int32_t      slot,
+                                     void             *data,
+                                     DBusFreeFunction  free_data_func)
+{
+  DBusFreeFunction old_free_func;
+  void *old_data;
+  dbus_bool_t retval;
+
+  retval = _dbus_data_slot_list_set (&slot_allocator,
+                                     &pending->slot_list,
+                                     slot, data, free_data_func,
+                                     &old_free_func, &old_data);
+
+  /* Drop locks to call out to app code */
+  CONNECTION_UNLOCK (pending->connection);
+  
+  if (retval)
+    {
+      if (old_free_func)
+        (* old_free_func) (old_data);
+    }
+
+  CONNECTION_LOCK (pending->connection);
+  
+  return retval;
+}
+
 /** @} */
 
 /**
@@ -129,6 +542,26 @@ _dbus_pending_call_notify (DBusPendingCall *pending)
  */
 
 /**
+ * @def DBUS_TIMEOUT_INFINITE
+ *
+ * An integer constant representing an infinite timeout. This has the
+ * numeric value 0x7fffffff (the largest 32-bit signed integer).
+ *
+ * For source compatibility with D-Bus versions earlier than 1.4.12, use
+ * 0x7fffffff, or INT32_MAX (assuming your platform has it).
+ */
+
+/**
+ * @def DBUS_TIMEOUT_USE_DEFAULT
+ *
+ * An integer constant representing a request to use the default timeout.
+ * This has numeric value -1.
+ *
+ * For source compatibility with D-Bus versions earlier than 1.4.12, use a
+ * literal -1.
+ */
+
+/**
  * @typedef DBusPendingCall
  *
  * Opaque data type representing a message pending.
@@ -138,13 +571,20 @@ _dbus_pending_call_notify (DBusPendingCall *pending)
  * Increments the reference count on a pending call.
  *
  * @param pending the pending call object
+ * @returns the pending call object
  */
-void
+DBusPendingCall *
 dbus_pending_call_ref (DBusPendingCall *pending)
 {
-  _dbus_return_if_fail (pending != NULL);
+  dbus_int32_t old_refcount;
 
-  _dbus_atomic_inc (&pending->refcount);
+  _dbus_return_val_if_fail (pending != NULL, NULL);
+
+  old_refcount = _dbus_atomic_inc (&pending->refcount);
+  _dbus_pending_call_trace_ref (pending, old_refcount, old_refcount + 1,
+      "ref");
+
+  return pending;
 }
 
 /**
@@ -156,43 +596,16 @@ dbus_pending_call_ref (DBusPendingCall *pending)
 void
 dbus_pending_call_unref (DBusPendingCall *pending)
 {
-  dbus_bool_t last_unref;
+  dbus_int32_t old_refcount;
 
   _dbus_return_if_fail (pending != NULL);
 
-  last_unref = (_dbus_atomic_dec (&pending->refcount) == 1);
+  old_refcount = _dbus_atomic_dec (&pending->refcount);
+  _dbus_pending_call_trace_ref (pending, old_refcount, old_refcount - 1,
+      "unref");
 
-  if (last_unref)
-    {
-      /* If we get here, we should be already detached
-       * from the connection, or never attached.
-       */
-      _dbus_assert (pending->connection == NULL);
-      _dbus_assert (!pending->timeout_added);  
-
-      /* this assumes we aren't holding connection lock... */
-      _dbus_data_slot_list_free (&pending->slot_list);
-      
-      if (pending->timeout != NULL)
-        _dbus_timeout_unref (pending->timeout);
-      
-      if (pending->timeout_link)
-        {
-          dbus_message_unref ((DBusMessage *)pending->timeout_link->data);
-          _dbus_list_free_link (pending->timeout_link);
-          pending->timeout_link = NULL;
-        }
-
-      if (pending->reply)
-        {
-          dbus_message_unref (pending->reply);
-          pending->reply = NULL;
-        }
-      
-      dbus_free (pending);
-
-      dbus_pending_call_free_data_slot (&notify_user_data_slot);
-    }
+  if (old_refcount == 1)
+    _dbus_pending_call_last_unref(pending);
 }
 
 /**
@@ -211,65 +624,98 @@ dbus_pending_call_set_notify (DBusPendingCall              *pending,
                               void                         *user_data,
                               DBusFreeFunction              free_user_data)
 {
+  dbus_bool_t ret = FALSE;
+
   _dbus_return_val_if_fail (pending != NULL, FALSE);
 
+  CONNECTION_LOCK (pending->connection);
+  
   /* could invoke application code! */
-  if (!dbus_pending_call_set_data (pending, notify_user_data_slot,
-                                   user_data, free_user_data))
-    return FALSE;
+  if (!_dbus_pending_call_set_data_unlocked (pending, notify_user_data_slot,
+                                             user_data, free_user_data))
+    goto out;
   
   pending->function = function;
+  ret = TRUE;
 
-  return TRUE;
+out:
+  CONNECTION_UNLOCK (pending->connection);
+  
+  return ret;
 }
 
 /**
- * Cancels the pending call, such that any reply
- * or error received will just be ignored.
- * Drops at least one reference to the #DBusPendingCall
- * so will free the call if nobody else is holding
- * a reference.
+ * Cancels the pending call, such that any reply or error received
+ * will just be ignored.  Drops the dbus library's internal reference
+ * to the #DBusPendingCall so will free the call if nobody else is
+ * holding a reference. However you usually get a reference from
+ * dbus_connection_send_with_reply() so probably your app owns a ref
+ * also.
+ *
+ * Note that canceling a pending call will <em>not</em> simulate a
+ * timed-out call; if a call times out, then a timeout error reply is
+ * received. If you cancel the call, no reply is received unless the
+ * the reply was already received before you canceled.
  * 
  * @param pending the pending call
  */
 void
 dbus_pending_call_cancel (DBusPendingCall *pending)
 {
-  if (pending->connection)
-    _dbus_connection_remove_pending_call (pending->connection,
-                                          pending);
+  _dbus_return_if_fail (pending != NULL);
+
+  _dbus_connection_remove_pending_call (pending->connection,
+                                        pending);
 }
 
 /**
  * Checks whether the pending call has received a reply
  * yet, or not.
  *
- * @todo not thread safe? I guess it has to lock though it sucks
- *
  * @param pending the pending call
- * @returns #TRUE if a reply has been received */
+ * @returns #TRUE if a reply has been received
+ */
 dbus_bool_t
 dbus_pending_call_get_completed (DBusPendingCall *pending)
 {
-  return pending->completed;
+  dbus_bool_t completed;
+  
+  _dbus_return_val_if_fail (pending != NULL, FALSE);
+
+  CONNECTION_LOCK (pending->connection);
+  completed = pending->completed;
+  CONNECTION_UNLOCK (pending->connection);
+
+  return completed;
 }
 
 /**
- * Gets the reply, or returns #NULL if none has been received yet. The
- * reference count is not incremented on the returned message, so you
- * have to keep a reference count on the pending call (or add one
- * to the message).
- *
- * @todo not thread safe? I guess it has to lock though it sucks
- * @todo maybe to make this threadsafe, it should be steal_reply(), i.e. only one thread can ever get the message
+ * Gets the reply, or returns #NULL if none has been received
+ * yet. Ownership of the reply message passes to the caller. This
+ * function can only be called once per pending call, since the reply
+ * message is tranferred to the caller.
  * 
  * @param pending the pending call
  * @returns the reply message or #NULL.
  */
 DBusMessage*
-dbus_pending_call_get_reply (DBusPendingCall *pending)
+dbus_pending_call_steal_reply (DBusPendingCall *pending)
 {
-  return pending->reply;
+  DBusMessage *message;
+  
+  _dbus_return_val_if_fail (pending != NULL, NULL);
+  _dbus_return_val_if_fail (pending->completed, NULL);
+  _dbus_return_val_if_fail (pending->reply != NULL, NULL);
+
+  CONNECTION_LOCK (pending->connection);
+  
+  message = pending->reply;
+  pending->reply = NULL;
+
+  CONNECTION_UNLOCK (pending->connection);
+
+  _dbus_message_trace_ref (message, -1, -1, "dbus_pending_call_steal_reply");
+  return message;
 }
 
 /**
@@ -283,29 +729,18 @@ dbus_pending_call_get_reply (DBusPendingCall *pending)
  *
  * @todo when you start blocking, the timeout is reset, but it should
  * really only use time remaining since the pending call was created.
+ * This requires storing timestamps instead of intervals in the timeout
  *
  * @param pending the pending call
  */
 void
 dbus_pending_call_block (DBusPendingCall *pending)
 {
-  DBusMessage *message;
-
-  if (dbus_pending_call_get_completed (pending))
-    return;
-  
-  message = _dbus_connection_block_for_reply (pending->connection,
-                                              pending->reply_serial,
-                                              dbus_timeout_get_interval (pending->timeout));
+  _dbus_return_if_fail (pending != NULL);
 
-  _dbus_connection_lock (pending->connection);
-  _dbus_pending_call_complete_and_unlock (pending, message);
-  dbus_message_unref (message);
+  _dbus_connection_block_pending_call (pending);
 }
 
-static DBusDataSlotAllocator slot_allocator;
-_DBUS_DEFINE_GLOBAL_LOCK (pending_call_slots);
-
 /**
  * Allocates an integer ID to be used for storing application-specific
  * data on any DBusPendingCall. The allocated ID may then be used
@@ -323,8 +758,9 @@ _DBUS_DEFINE_GLOBAL_LOCK (pending_call_slots);
 dbus_bool_t
 dbus_pending_call_allocate_data_slot (dbus_int32_t *slot_p)
 {
+  _dbus_return_val_if_fail (slot_p != NULL, FALSE);
+
   return _dbus_data_slot_allocator_alloc (&slot_allocator,
-                                          _DBUS_LOCK_NAME (pending_call_slots),
                                           slot_p);
 }
 
@@ -342,8 +778,9 @@ dbus_pending_call_allocate_data_slot (dbus_int32_t *slot_p)
 void
 dbus_pending_call_free_data_slot (dbus_int32_t *slot_p)
 {
+  _dbus_return_if_fail (slot_p != NULL);
   _dbus_return_if_fail (*slot_p >= 0);
-  
+
   _dbus_data_slot_allocator_free (&slot_allocator, slot_p);
 }
 
@@ -366,24 +803,15 @@ dbus_pending_call_set_data (DBusPendingCall  *pending,
                             void             *data,
                             DBusFreeFunction  free_data_func)
 {
-  DBusFreeFunction old_free_func;
-  void *old_data;
   dbus_bool_t retval;
-
+  
   _dbus_return_val_if_fail (pending != NULL, FALSE);
   _dbus_return_val_if_fail (slot >= 0, FALSE);
 
-  retval = _dbus_data_slot_list_set (&slot_allocator,
-                                     &pending->slot_list,
-                                     slot, data, free_data_func,
-                                     &old_free_func, &old_data);
-
-  if (retval)
-    {
-      if (old_free_func)
-        (* old_free_func) (old_data);
-    }
-
+  
+  CONNECTION_LOCK (pending->connection);
+  retval = _dbus_pending_call_set_data_unlocked (pending, slot, data, free_data_func);
+  CONNECTION_UNLOCK (pending->connection);
   return retval;
 }
 
@@ -403,27 +831,13 @@ dbus_pending_call_get_data (DBusPendingCall   *pending,
 
   _dbus_return_val_if_fail (pending != NULL, NULL);
 
+  CONNECTION_LOCK (pending->connection);
   res = _dbus_data_slot_list_get (&slot_allocator,
                                   &pending->slot_list,
                                   slot);
+  CONNECTION_UNLOCK (pending->connection);
 
   return res;
 }
 
 /** @} */
-
-#ifdef DBUS_BUILD_TESTS
-
-/**
- * @ingroup DBusPendingCallInternals
- * Unit test for DBusPendingCall.
- *
- * @returns #TRUE on success.
- */
-dbus_bool_t
-_dbus_pending_call_test (const char *test_data_dir)
-{  
-
-  return TRUE;
-}
-#endif /* DBUS_BUILD_TESTS */