diff options
Diffstat (limited to 'dbus/dbus-message.c')
| -rw-r--r-- | dbus/dbus-message.c | 116 |
1 files changed, 116 insertions, 0 deletions
diff --git a/dbus/dbus-message.c b/dbus/dbus-message.c index 4d80425b..85d6ce9e 100644 --- a/dbus/dbus-message.c +++ b/dbus/dbus-message.c @@ -29,6 +29,7 @@ #include "dbus-memory.h" #include "dbus-list.h" #include "dbus-message-builder.h" +#include "dbus-dataslot.h" #include <string.h> /** @@ -107,6 +108,8 @@ struct DBusMessage dbus_uint32_t changed_stamp; /**< Incremented when iterators are invalidated. */ unsigned int locked : 1; /**< Message being sent, no modifications allowed. */ + + DBusDataSlotList slot_list; /**< Data stored by allocated integer ID */ }; enum { @@ -913,6 +916,8 @@ dbus_message_new_empty_header (void) message->byte_order = DBUS_COMPILER_BYTE_ORDER; message->client_serial = 0; message->reply_serial = 0; + + _dbus_data_slot_list_init (&message->slot_list); i = 0; while (i < FIELD_LAST) @@ -1184,6 +1189,9 @@ dbus_message_unref (DBusMessage *message) if (old_refcount == 1) { + /* This calls application callbacks! */ + _dbus_data_slot_list_free (&message->slot_list); + _dbus_list_foreach (&message->size_counters, free_size_counter, message); _dbus_list_clear (&message->size_counters); @@ -4609,6 +4617,114 @@ _dbus_message_loader_get_max_message_size (DBusMessageLoader *loader) return loader->max_message_size; } +static DBusDataSlotAllocator slot_allocator; +_DBUS_DEFINE_GLOBAL_LOCK (message_slots); + +/** + * Allocates an integer ID to be used for storing application-specific + * data on any DBusMessage. The allocated ID may then be used + * with dbus_message_set_data() and dbus_message_get_data(). + * The passed-in slot must be initialized to -1, and is filled in + * with the slot ID. If the passed-in slot is not -1, it's assumed + * to be already allocated, and its refcount is incremented. + * + * The allocated slot is global, i.e. all DBusMessage objects will + * have a slot with the given integer ID reserved. + * + * @param slot_p address of a global variable storing the slot + * @returns #FALSE on failure (no memory) + */ +dbus_bool_t +dbus_message_allocate_data_slot (dbus_int32_t *slot_p) +{ + return _dbus_data_slot_allocator_alloc (&slot_allocator, + _DBUS_LOCK_NAME (message_slots), + slot_p); +} + +/** + * Deallocates a global ID for message data slots. + * dbus_message_get_data() and dbus_message_set_data() may no + * longer be used with this slot. Existing data stored on existing + * DBusMessage objects will be freed when the message is + * finalized, but may not be retrieved (and may only be replaced if + * someone else reallocates the slot). When the refcount on the + * passed-in slot reaches 0, it is set to -1. + * + * @param slot_p address storing the slot to deallocate + */ +void +dbus_message_free_data_slot (dbus_int32_t *slot_p) +{ + _dbus_return_if_fail (*slot_p >= 0); + + _dbus_data_slot_allocator_free (&slot_allocator, slot_p); +} + +/** + * Stores a pointer on a DBusMessage, along + * with an optional function to be used for freeing + * the data when the data is set again, or when + * the message is finalized. The slot number + * must have been allocated with dbus_message_allocate_data_slot(). + * + * @param message the message + * @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_message_set_data (DBusMessage *message, + dbus_int32_t slot, + void *data, + DBusFreeFunction free_data_func) +{ + DBusFreeFunction old_free_func; + void *old_data; + dbus_bool_t retval; + + _dbus_return_val_if_fail (message != NULL, FALSE); + _dbus_return_val_if_fail (slot >= 0, FALSE); + + retval = _dbus_data_slot_list_set (&slot_allocator, + &message->slot_list, + slot, data, free_data_func, + &old_free_func, &old_data); + + if (retval) + { + /* Do the actual free outside the message lock */ + if (old_free_func) + (* old_free_func) (old_data); + } + + return retval; +} + +/** + * Retrieves data previously set with dbus_message_set_data(). + * The slot must still be allocated (must not have been freed). + * + * @param message the message + * @param slot the slot to get data from + * @returns the data, or #NULL if not found + */ +void* +dbus_message_get_data (DBusMessage *message, + dbus_int32_t slot) +{ + void *res; + + _dbus_return_val_if_fail (message != NULL, NULL); + + res = _dbus_data_slot_list_get (&slot_allocator, + &message->slot_list, + slot); + + return res; +} + /** @} */ #ifdef DBUS_BUILD_TESTS #include "dbus-test.h" |