2003-07-08 Havoc Pennington <hp@pobox.com>

	* dbus/dbus-object.h: sketch out an API for registering objects
	with a connection, that allows us to use as little as 24 bytes
	per object and lets application code represent an object in
	any conceivable way.

	* dbus/dbus-object-registry.c: implement the hard bits of the
	DBusConnection aspect of object API. Not yet wired up.

12 files changed, 521 insertions, 0 deletions

diff --git a/dbus/Makefile.am b/dbus/Makefile.am
index 3c3c14e7..8c919f31 100644
--- a/dbus/Makefile.am
+++ b/dbus/Makefile.am
@@ -17,6 +17,7 @@ dbusinclude_HEADERS=				\
 	dbus-memory.h				\
 	dbus-message.h				\
 	dbus-message-handler.h			\
+	dbus-object.h				\
 	dbus-objectid.h				\
 	dbus-protocol.h				\
 	dbus-server.h				\
@@ -43,7 +44,10 @@ DBUS_LIB_SOURCES=				\
 	dbus-message.c				\
 	dbus-message-handler.c			\
 	dbus-message-internal.h			\
+	dbus-object.c				\
 	dbus-objectid.c				\
+	dbus-object-registry.c			\
+	dbus-object-registry.h			\
 	dbus-resources.c			\
 	dbus-resources.h			\
 	dbus-server.c				\
diff --git a/dbus/dbus-connection-internal.h b/dbus/dbus-connection-internal.h
index 5ddc0e0a..eaa35955 100644
--- a/dbus/dbus-connection-internal.h
+++ b/dbus/dbus-connection-internal.h
@@ -81,6 +81,7 @@ void              _dbus_message_handler_remove_connection      (DBusMessageHandl
 DBusHandlerResult _dbus_message_handler_handle_message         (DBusMessageHandler *handler,
                                                                 DBusConnection     *connection,
                                                                 DBusMessage        *message);
+dbus_uint32_t     _dbus_connection_get_id                      (DBusConnection     *connection);
 
 DBUS_END_DECLS;
 
diff --git a/dbus/dbus-connection.c b/dbus/dbus-connection.c
index 01b2a7bf..237c195b 100644
--- a/dbus/dbus-connection.c
+++ b/dbus/dbus-connection.c
@@ -920,6 +920,22 @@ _dbus_connection_handle_watch (DBusWatch                   *watch,
   return retval;
 }
 
+/**
+ * Get the ID to be used in the high bits of an object ID for an object
+ * registered with this connection.
+ *
+ * @todo implement this function
+ * 
+ * @param connection the connection.
+ * @returns the connection portion of the object ID
+ */
+dbus_uint32_t
+_dbus_connection_get_id (DBusConnection *connection)
+{
+  /* FIXME */
+  return 1492;
+}
+
 /** @} */
 
 /**
diff --git a/dbus/dbus-connection.h b/dbus/dbus-connection.h
index 9f4dd7ae..ce57c98d 100644
--- a/dbus/dbus-connection.h
+++ b/dbus/dbus-connection.h
@@ -37,6 +37,7 @@ typedef struct DBusConnection DBusConnection;
 typedef struct DBusWatch DBusWatch;
 typedef struct DBusTimeout DBusTimeout;
 typedef struct DBusMessageHandler DBusMessageHandler;
+typedef struct DBusObject DBusObject;
 typedef struct DBusPreallocatedSend DBusPreallocatedSend;
 
 typedef enum
diff --git a/dbus/dbus-object-registry.c b/dbus/dbus-object-registry.c
new file mode 100644
index 00000000..9f7ca3ff
--- /dev/null
+++ b/dbus/dbus-object-registry.c
@@ -0,0 +1,325 @@
+/* -*- mode: C; c-file-style: "gnu" -*- */
+/* dbus-object-registry.c  DBusObjectRegistry (internals of DBusConnection)
+ *
+ * Copyright (C) 2003  Red Hat Inc.
+ *
+ * Licensed under the Academic Free License version 1.2
+ *
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * 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
+ *
+ */
+#include "dbus-object-registry.h"
+#include "dbus-connection-internal.h"
+#include "dbus-internals.h"
+#include <string.h>
+
+/**
+ * @defgroup DBusObjectRegistry Map object IDs to implementations
+ * @ingroup  DBusInternals
+ * @brief DBusObjectRegistry is used by DBusConnection to track object IDs
+ *
+ * Types and functions related to DBusObjectRegistry
+ *
+ * @{
+ */
+
+typedef struct DBusObjectEntry DBusObjectEntry;
+
+ /* 14 bits for object index, 32K objects */
+#define DBUS_OBJECT_INDEX_BITS          (14)
+#define DBUS_OBJECT_INDEX_MASK          (0x7fff)
+#define DBUS_MAX_OBJECTS_PER_CONNECTION DBUS_OBJECT_INDEX_MASK
+struct DBusObjectEntry
+{
+  unsigned int id_index      : 14; /**< Index of this entry in the entries array */
+  unsigned int id_times_used : 18; /**< Count of times entry has been used; avoids recycling IDs too often */
+
+  void *object_impl;               /**< Pointer to application-supplied implementation */
+  const DBusObjectVTable *vtable;  /**< Virtual table for this object */
+};
+
+struct DBusObjectRegistry
+{
+  int refcount;
+  DBusConnection *connection;
+
+  DBusObjectEntry *entries;
+  int n_entries_allocated;
+  int n_entries_used;
+};
+
+DBusObjectRegistry*
+_dbus_object_registry_new (DBusConnection *connection)
+{
+  DBusObjectRegistry *registry;
+
+  registry = dbus_new0 (DBusObjectRegistry, 1);
+
+  registry->refcount = 1;
+  registry->connection = connection;
+
+  return registry;
+}
+
+void
+_dbus_object_registry_ref (DBusObjectRegistry *registry)
+{
+  _dbus_assert (registry->refcount > 0);
+
+  registry->refcount += 1;
+}
+
+void
+_dbus_object_registry_unref (DBusObjectRegistry *registry)
+{
+  _dbus_assert (registry->refcount > 0);
+
+  registry->refcount -= 1;
+
+  if (registry->refcount == 0)
+    {
+      _dbus_assert (registry->n_entries_used == 0);
+
+      dbus_free (registry->entries);
+      dbus_free (registry);
+    }
+}
+
+#define ENTRY_TO_ID(entry)                                              \
+  (((dbus_uint32_t) (entry)->id_index) |                                \
+   (((dbus_uint32_t)(entry)->id_times_used) << DBUS_OBJECT_INDEX_BITS))
+
+#define ID_TO_INDEX(id) \
+  (((dbus_uint32_t) (id)) | DBUS_OBJECT_INDEX_MASK)
+
+#define ID_TO_TIMES_USED(id) \
+  (((dbus_uint32_t) (id)) >> DBUS_OBJECT_INDEX_BITS)
+
+static DBusObjectEntry*
+validate_id (DBusObjectRegistry *registry,
+             const DBusObjectID *object_id)
+{
+  int idx;
+  int times_used;
+  dbus_uint32_t low_bits;
+
+  low_bits = dbus_object_id_get_low_bits (object_id);
+
+  idx = ID_TO_INDEX (low_bits);
+  times_used = ID_TO_TIMES_USED (low_bits);
+
+  if (idx >= registry->n_entries_allocated)
+    return NULL;
+  if (registry->entries[idx].vtable == NULL)
+    return NULL;
+  if (registry->entries[idx].id_times_used != times_used)
+    return NULL;
+  _dbus_assert (registry->entries[idx].id_index == idx);
+  _dbus_assert (registry->n_entries_used > 0);
+
+  return &registry->entries[idx];
+}
+
+static void
+info_from_entry (DBusObjectRegistry *registry,
+                 DBusObjectInfo     *info,
+                 DBusObjectEntry    *entry)
+{
+  info->connection = registry->connection;
+  info->object_impl = entry->object_impl;
+  dbus_object_id_set_high_bits (&info->object_id,
+                                _dbus_connection_get_id (registry->connection));
+  dbus_object_id_set_low_bits (&info->object_id,
+                               ENTRY_TO_ID (entry));
+}
+
+dbus_bool_t
+_dbus_object_registry_add_and_unlock (DBusObjectRegistry      *registry,
+                                      const char             **interfaces,
+                                      const DBusObjectVTable  *vtable,
+                                      void                    *object_impl,
+                                      DBusObjectID            *object_id)
+{
+  int i;
+  DBusObjectInfo info;
+
+  if (registry->n_entries_used == registry->n_entries_allocated)
+    {
+      DBusObjectEntry *new_entries;
+      int new_alloc;
+
+      if (registry->n_entries_allocated == 0)
+        new_alloc = 16;
+      else
+        {
+          if (registry->n_entries_allocated == DBUS_MAX_OBJECTS_PER_CONNECTION)
+            {
+              _dbus_warn ("Attempting to register a new D-BUS object, but maximum object count of %d reached\n",
+                          DBUS_MAX_OBJECTS_PER_CONNECTION);
+              return FALSE;
+            }
+
+          new_alloc = registry->n_entries_allocated * 2;
+          if (new_alloc > DBUS_MAX_OBJECTS_PER_CONNECTION)
+            new_alloc = DBUS_MAX_OBJECTS_PER_CONNECTION;
+        }
+
+      new_entries = dbus_realloc (registry->entries,
+                                  new_alloc * sizeof (DBusObjectEntry));
+
+      if (new_entries == NULL)
+        return FALSE;
+
+      memset (&new_entries[registry->n_entries_allocated],
+              '\0',
+              sizeof (DBusObjectEntry) * (new_alloc - registry->n_entries_allocated));
+
+      registry->entries = new_entries;
+      registry->n_entries_allocated = new_alloc;
+    }
+  _dbus_assert (registry->n_entries_used < registry->n_entries_allocated);
+
+  /* We linear search for an available entry. However, short-circuit
+   * the hopefully-common situation where we don't have a sparse
+   * array.
+   */
+  if (registry->entries[registry->n_entries_used].vtable == NULL)
+    {
+      i = registry->n_entries_used;
+    }
+  else
+    {
+      /* If we do have a sparse array, we try to get rid of it rather
+       * than using empty slots on the end, so we won't hit this case
+       * next time.
+       */
+
+      /* If index n_entries_used is occupied, then
+       * there is at least one entry outside of
+       * the range [0, n_entries_used). Thus, there is
+       * at least one blank entry inside that range.
+       */
+      i = 0;
+      while (i < registry->n_entries_used)
+        {
+          if (registry->entries[i].vtable == NULL)
+            break;
+          ++i;
+        }
+
+      _dbus_assert (i < registry->n_entries_used);
+    }
+
+  registry->entries[i].id_index = i;
+  /* Overflow is OK here */
+  registry->entries[i].id_times_used += 1;
+
+  registry->entries[i].vtable = vtable;
+  registry->entries[i].object_impl = object_impl;
+
+  info_from_entry (registry, &info, &registry->entries[i]);
+
+  /* Drop lock and invoke application code */
+  _dbus_connection_unlock (registry->connection);
+
+  (* vtable->registered) (&info);
+
+  return TRUE;
+}
+
+void
+_dbus_object_registry_remove_and_unlock (DBusObjectRegistry *registry,
+                                         const DBusObjectID *object_id)
+{
+  DBusObjectInfo info;
+  DBusObjectEntry *entry;
+  const DBusObjectVTable *vtable;
+
+  entry = validate_id (registry, object_id);
+  if (entry == NULL)
+    {
+      _dbus_warn ("Tried to unregister a nonexistent D-BUS object ID\n");
+      return;
+    }
+
+  info_from_entry (registry, &info, entry);
+  vtable = entry->vtable;
+  entry->vtable = NULL;
+  entry->object_impl = NULL;
+  registry->n_entries_used -= 1;
+
+  /* Drop lock and invoke application code */
+  _dbus_connection_unlock (registry->connection);
+
+  (* vtable->unregistered) (&info);
+}
+
+void
+_dbus_object_registry_handle_and_unlock (DBusObjectRegistry *registry,
+                                         DBusMessage        *message)
+{
+  /* FIXME */
+}
+
+void
+_dbus_object_registry_free_all_unlocked (DBusObjectRegistry *registry)
+{
+  int i;
+
+  i = 0;
+  while (registry->n_entries_used > 0)
+    {
+      _dbus_assert (i < registry->n_entries_allocated);
+      if (registry->entries[i].vtable != NULL)
+        {
+          DBusObjectInfo info;
+          const DBusObjectVTable *vtable;
+
+          info_from_entry (registry, &info, &registry->entries[i]);
+          vtable = registry->entries[i].vtable;
+          registry->entries[i].vtable = NULL;
+          registry->entries[i].object_impl = NULL;
+          registry->n_entries_used -= 1;
+          _dbus_assert (registry->n_entries_used >= 0);
+
+          (* vtable->unregistered) (&info);
+        }
+
+      ++i;
+    }
+
+  _dbus_assert (registry->n_entries_used == 0);
+}
+
+/** @} */
+
+#ifdef DBUS_BUILD_TESTS
+#include "dbus-test.h"
+#include <stdio.h>
+
+/**
+ * @ingroup DBusObjectRegistry
+ * Unit test for DBusObjectRegistry
+ * @returns #TRUE on success.
+ */
+dbus_bool_t
+_dbus_object_registry_test (void)
+{
+
+
+  return TRUE;
+}
+
+#endif /* DBUS_BUILD_TESTS */
diff --git a/dbus/dbus-object-registry.h b/dbus/dbus-object-registry.h
new file mode 100644
index 00000000..d33664e5
--- /dev/null
+++ b/dbus/dbus-object-registry.h
@@ -0,0 +1,50 @@
+/* -*- mode: C; c-file-style: "gnu" -*- */
+/* dbus-object-registry.h  DBusObjectRegistry (internals of DBusConnection)
+ *
+ * Copyright (C) 2003  Red Hat Inc.
+ *
+ * Licensed under the Academic Free License version 1.2
+ * 
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * 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
+ *
+ */
+#ifndef DBUS_OBJECT_REGISTRY_H
+#define DBUS_OBJECT_REGISTRY_H
+
+#include <dbus/dbus-object.h>
+
+DBUS_BEGIN_DECLS;
+
+typedef struct DBusObjectRegistry DBusObjectRegistry;
+
+DBusObjectRegistry* _dbus_object_registry_new   (DBusConnection     *connection);
+void                _dbus_object_registry_ref   (DBusObjectRegistry *registry);
+void                _dbus_object_registry_unref (DBusObjectRegistry *registry);
+
+dbus_bool_t _dbus_object_registry_add_and_unlock    (DBusObjectRegistry      *registry,
+                                                     const char             **interfaces,
+                                                     const DBusObjectVTable  *vtable,
+                                                     void                    *object_impl,
+                                                     DBusObjectID            *object_id);
+void        _dbus_object_registry_remove_and_unlock (DBusObjectRegistry      *registry,
+                                                     const DBusObjectID      *object_id);
+void        _dbus_object_registry_handle_and_unlock (DBusObjectRegistry      *registry,
+                                                     DBusMessage             *message);
+void        _dbus_object_registry_free_all_unlocked (DBusObjectRegistry      *registry);
+
+
+DBUS_END_DECLS;
+
+#endif /* DBUS_OBJECT_REGISTRY_H */
diff --git a/dbus/dbus-object.c b/dbus/dbus-object.c
new file mode 100644
index 00000000..fdd33dd4
--- /dev/null
+++ b/dbus/dbus-object.c
@@ -0,0 +1,27 @@
+/* -*- mode: C; c-file-style: "gnu" -*- */
+/* dbus-object.c  DBusObject type
+ *
+ * Copyright (C) 2003  Red Hat Inc.
+ *
+ * Licensed under the Academic Free License version 1.2
+ * 
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * 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
+ *
+ */
+
+#include <config.h>
+#include "dbus-internals.h"
+#include "dbus-object.h"
+
diff --git a/dbus/dbus-object.h b/dbus/dbus-object.h
new file mode 100644
index 00000000..0c92776d
--- /dev/null
+++ b/dbus/dbus-object.h
@@ -0,0 +1,85 @@
+/* -*- mode: C; c-file-style: "gnu" -*- */
+/* dbus-object.h  DBusObject type
+ *
+ * Copyright (C) 2003  Red Hat Inc.
+ *
+ * Licensed under the Academic Free License version 1.2
+ * 
+ * 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
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * 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
+ *
+ */
+#if !defined (DBUS_INSIDE_DBUS_H) && !defined (DBUS_COMPILATION)
+#error "Only <dbus/dbus.h> can be included directly, this file may disappear or change contents."
+#endif
+
+#ifndef DBUS_OBJECT_H
+#define DBUS_OBJECT_H
+
+#include <dbus/dbus-arch-deps.h>
+#include <dbus/dbus-types.h>
+#include <dbus/dbus-objectid.h>
+#include <dbus/dbus-connection.h>
+
+DBUS_BEGIN_DECLS;
+
+typedef struct DBusObjectVTable   DBusObjectVTable;
+typedef struct DBusObjectInfo     DBusObjectInfo;
+typedef struct DBusCallbackObject DBusCallbackObject;
+
+struct DBusObjectInfo
+{
+  void               *object_impl;
+  DBusObjectID        object_id;
+  DBusConnection     *connection;
+};
+
+typedef void (* DBusObjectRegisteredFunction)   (DBusObjectInfo *info);
+typedef void (* DBusObjectUnregisteredFunction) (DBusObjectInfo *info);
+typedef void (* DBusObjectMessageFunction)      (DBusObjectInfo *info,
+                                                 DBusMessage    *message);
+
+struct DBusObjectVTable
+{
+  DBusObjectRegisteredFunction   registered;
+  DBusObjectUnregisteredFunction unregistered;
+  DBusObjectMessageFunction      message;
+};
+
+dbus_bool_t dbus_connection_register_object   (DBusConnection          *connection,
+                                               const char             **interfaces,
+                                               const DBusObjectVTable  *vtable,
+                                               void                    *object_impl,
+                                               DBusObjectID            *object_id);
+void        dbus_connection_unregister_object (DBusConnection          *connection,
+                                               const DBusObjectID      *object_id);
+
+extern const DBusObjectVTable *dbus_callback_object_vtable;
+
+DBusCallbackObject* dbus_callback_object_new          (DBusObjectMessageFunction   function,
+                                                       void                       *user_data,
+                                                       DBusFreeFunction            free_user_data);
+void                dbus_callback_object_ref          (DBusCallbackObject         *handler);
+void                dbus_callback_object_unref        (DBusCallbackObject         *handler);
+void*               dbus_callback_object_get_data     (DBusCallbackObject         *handler);
+void                dbus_callback_object_set_data     (DBusCallbackObject         *handler,
+                                                       void                       *data,
+                                                       DBusFreeFunction            free_user_data);
+void                dbus_callback_object_set_function (DBusCallbackObject         *handler,
+                                                       DBusObjectMessageFunction   function);
+
+
+DBUS_END_DECLS;
+
+#endif /* DBUS_OBJECT_H */
diff --git a/dbus/dbus-objectid.h b/dbus/dbus-objectid.h
index 57346910..b5e1f606 100644
--- a/dbus/dbus-objectid.h
+++ b/dbus/dbus-objectid.h
@@ -30,6 +30,8 @@
 #include <dbus/dbus-arch-deps.h>
 #include <dbus/dbus-types.h>
 
+DBUS_BEGIN_DECLS;
+
 typedef struct DBusObjectID DBusObjectID;
 
 struct DBusObjectID
@@ -58,4 +60,6 @@ void                   dbus_object_id_set_as_integer (DBusObjectID       *obj_id
                                                       dbus_uint64_t       value);
 #endif
 
+DBUS_END_DECLS;
+
 #endif /* DBUS_OBJECTID_H */
diff --git a/dbus/dbus-test.c b/dbus/dbus-test.c
index 3d5d14bb..220961c7 100644
--- a/dbus/dbus-test.c
+++ b/dbus/dbus-test.c
@@ -105,6 +105,12 @@ dbus_internal_do_not_use_run_tests (const char *test_data_dir)
     die ("object ID");
   
   check_memleaks ();
+
+  printf ("%s: running object registry tests\n", "dbus-test");
+  if (!_dbus_object_registry_test ())
+    die ("object registry");
+  
+  check_memleaks ();
   
   printf ("%s: running marshalling tests\n", "dbus-test");
   if (!_dbus_marshal_test ())
diff --git a/dbus/dbus-test.h b/dbus/dbus-test.h
index 512cb9a6..c9555e2d 100644
--- a/dbus/dbus-test.h
+++ b/dbus/dbus-test.h
@@ -54,6 +54,7 @@ dbus_bool_t _dbus_spawn_test           (const char *test_data_dir);
 dbus_bool_t _dbus_userdb_test          (const char *test_data_dir);
 dbus_bool_t _dbus_memory_test	       (void);
 dbus_bool_t _dbus_object_id_test       (void);
+dbus_bool_t _dbus_object_registry_test (void);
 
 
 void        dbus_internal_do_not_use_run_tests         (const char          *test_data_dir);
diff --git a/dbus/dbus.h b/dbus/dbus.h
index 38db4f5b..d83a4a50 100644
--- a/dbus/dbus.h
+++ b/dbus/dbus.h
@@ -38,6 +38,7 @@
 #include <dbus/dbus-macros.h>
 #include <dbus/dbus-message.h>
 #include <dbus/dbus-message-handler.h>
+#include <dbus/dbus-object.h>
 #include <dbus/dbus-objectid.h>
 #include <dbus/dbus-protocol.h>
 #include <dbus/dbus-server.h>