## TpMessageMixin TpMessageMixin — a mixin implementation of the text channel type and the Messages interface |

## Synopsis

    #include <telepathy-glib/message-mixin.h>

                        TpMessage;
    guint               tp_message_append_part              (TpMessage *self);
    guint               tp_message_count_parts              (TpMessage *self);
    gboolean            tp_message_delete_key               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key);
    void                tp_message_delete_part              (TpMessage *self,
                                                             guint part);
    void                tp_message_destroy                  (TpMessage *self);
    TpMessage*          tp_message_new                      (TpBaseConnection *connection,
                                                             guint initial_parts,
                                                             guint size_hint);
    const GHashTable*   tp_message_peek                     (TpMessage *self,
                                                             guint part);
    void                tp_message_ref_handle               (TpMessage *self,
                                                             TpHandleType handle_type,
                                                             TpHandle handle);
    void                tp_message_set                      (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const GValue *source);
    void                tp_message_set_boolean              (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gboolean b);
    void                tp_message_set_bytes                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint len,
                                                             gconstpointer bytes);
    void                tp_message_set_handle               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             TpHandleType handle_type,
                                                             TpHandle handle_or_0);
    #define             tp_message_set_int16                (s, p, k, i)
    void                tp_message_set_int32                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gint32 i);
    void                tp_message_set_int64                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gint64 i);
    void                tp_message_set_string               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const gchar *s);
    void                tp_message_set_string_printf        (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const gchar *fmt,
                                                             ...);
    #define             tp_message_set_uint16               (s, p, k, u)
    void                tp_message_set_uint32               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint32 u);
    void                tp_message_set_uint64               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint64 u);
    void                tp_message_take_message             (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             TpMessage *message);
                        TpMessageMixin;
    void                (*TpMessageMixinSendImpl)           (GObject *object,
                                                             TpMessage *message,
                                                             TpMessageSendingFlags flags);
    void                tp_message_mixin_finalize           (GObject *obj);
    void                tp_message_mixin_implement_sending  (GObject *object,
                                                             TpMessageMixinSendImpl send,
                                                             guint n_types,
                                                             const TpChannelTextMessageType *types,
                                                             TpMessagePartSupportFlags message_part_support_flags,
                                                             TpDeliveryReportingSupportFlags delivery_reporting_support_flags,
                                                             const gchar * const *supported_content_types);
    void                tp_message_mixin_init               (GObject *obj,
                                                             gsize offset,
                                                             TpBaseConnection *connection);
    void                tp_message_mixin_init_dbus_properties
                                                            (GObjectClass *cls);
    void                tp_message_mixin_messages_iface_init
                                                            (gpointer g_iface,
                                                             gpointer iface_data);
    void                tp_message_mixin_get_dbus_property  (GObject *object,
                                                             GQuark interface,
                                                             GQuark name,
                                                             GValue *value,
                                                             gpointer unused);
    void                tp_message_mixin_sent               (GObject *object,
                                                             TpMessage *message,
                                                             TpMessageSendingFlags flags,
                                                             const gchar *token,
                                                             const GError *error);
    void                tp_message_mixin_set_rescued        (GObject *obj);
    guint               tp_message_mixin_take_received      (GObject *object,
                                                             TpMessage *message);
    gboolean            tp_message_mixin_has_pending_messages
                                                            (GObject *object,
                                                             TpHandle *first_sender);
    void                tp_message_mixin_clear              (GObject *obj);
    void                tp_message_mixin_text_iface_init    (gpointer g_iface,
                                                             gpointer iface_data);

## Description

This mixin can be added to a channel GObject class to implement the text channel type (with the Messages interface) in a general way. The channel class should also have a TpDBusPropertiesMixinClass.

To use the messages mixin, include a TpMessageMixin somewhere in your instance structure, and call `tp_message_mixin_init()` from your constructor function, and `tp_message_mixin_finalize()` from your dispose or finalize function. In the class_init function, call `tp_message_mixin_init_dbus_properties()` to hook this mixin into the D-Bus properties mixin class. Finally, include the following in the fourth argument of `G_DEFINE_TYPE_WITH_CODE()`:

     G_IMPLEMENT_INTERFACE (TP_TYPE_SVC_CHANNEL_TYPE_TEXT,
       tp_message_mixin_text_iface_init);
     G_IMPLEMENT_INTERFACE (TP_TYPE_SVC_CHANNEL_INTERFACE_MESSAGES,
       tp_message_mixin_messages_iface_init);

To support sending messages, you must call `tp_message_mixin_implement_sending()` in the constructor function. If you do not, any attempt to send a message will fail with NotImplemented.

`since` 0.7.UNRELEASED

## Details

### TpMessage

    typedef struct _TpMessage TpMessage;

Opaque structure representing a message in the Telepathy messages interface (an array of at least one mapping from string to variant, where the first mapping contains message headers and subsequent mappings contain the message body).

### tp_message_append_part ()

    guint               tp_message_append_part              (TpMessage *self);

Append a body part to the message.

`self` : | a message
Returns : | the part number `since` 0.7.UNRELEASED

### tp_message_count_parts ()

    guint               tp_message_count_parts              (TpMessage *self);

`self` : | a message
Returns : | the number of parts in the message, including the headers in part 0 `since` 0.7.UNRELEASED

### tp_message_delete_key ()

    gboolean            tp_message_delete_key               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key);

Remove the given key and its value from the given part.

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
Returns : | `TRUE` if the key previously existed `since` 0.7.UNRELEASED

### tp_message_delete_part ()

    void                tp_message_delete_part              (TpMessage *self,
                                                             guint part);

Delete the given body part from the message.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly greater than 0, and strictly less than the number returned by `tp_message_count_parts()`

### tp_message_destroy ()

    void                tp_message_destroy                  (TpMessage *self);

Destroy `self`.

`since` 0.7.UNRELEASED

`self` : | a message

### tp_message_new ()

    TpMessage*          tp_message_new                      (TpBaseConnection *connection,
                                                             guint initial_parts,
                                                             guint size_hint);

`connection` : | a connection on which to reference handles
`initial_parts` : | number of parts to create (at least 1)
`size_hint` : | preallocate space for this many parts (at least `initial_parts`)
Returns : | a newly allocated message suitable to be passed to tp_message_mixin_take_received `since` 0.7.UNRELEASED

### tp_message_peek ()

    const GHashTable*   tp_message_peek                     (TpMessage *self,
                                                             guint part);

`self` : | a message
`part` : | a part number
Returns : | the GHashTable used to implement the given part, or `NULL` if the part number is out of range. The hash table is only valid as long as the message is valid and the part is not deleted. `since` 0.7.UNRELEASED

### tp_message_ref_handle ()

    void                tp_message_ref_handle               (TpMessage *self,
                                                             TpHandleType handle_type,
                                                             TpHandle handle);

Reference the given handle until this message is destroyed.

`since` 0.7.UNRELEASED

`self` : | a message
`handle_type` : | a handle type, greater than `TP_HANDLE_TYPE_NONE` and less than `NUM_TP_HANDLE_TYPES`
`handle` : | a handle of the given type

### tp_message_set ()

    void                tp_message_set                      (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const GValue *source);

Set `key` in part `part` of `self` to have a copy of `source` as its value.

If `source` represents a data structure containing handles, they should all be referenced with `tp_message_ref_handle()` first.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`source` : | a value

### tp_message_set_boolean ()

    void                tp_message_set_boolean              (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gboolean b);

Set `key` in part `part` of `self` to have `b` as a boolean value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`b` : | a boolean value

### tp_message_set_bytes ()

    void                tp_message_set_bytes                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint len,
                                                             gconstpointer bytes);

Set `key` in part `part` of `self` to have `bytes` as a byte-array value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`len` : | a number of bytes
`bytes` : | an array of `len` bytes

### tp_message_set_handle ()

    void                tp_message_set_handle               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             TpHandleType handle_type,
                                                             TpHandle handle_or_0);

If `handle_or_0` is not zero, reference it with `tp_message_ref_handle()`.

Set `key` in part `part` of `self` to have `handle_or_0` as an unsigned integer value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`handle_type` : | a handle type
`handle_or_0` : | a handle of that type, or 0

### tp_message_set_int16()

    #define             tp_message_set_int16(s, p, k, i)

Set `key` in part `part` of `self` to have `i` as a signed integer value.

`since` 0.7.UNRELEASED

`s` : | a message
`p` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`k` : | a key in the mapping representing the part
`i` : | an integer value

### tp_message_set_int32 ()

    void                tp_message_set_int32                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gint32 i);

Set `key` in part `part` of `self` to have `i` as a signed integer value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`i` : | an integer value

### tp_message_set_int64 ()

    void                tp_message_set_int64                (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             gint64 i);

Set `key` in part `part` of `self` to have `i` as a signed integer value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`i` : | an integer value

### tp_message_set_string ()

    void                tp_message_set_string               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const gchar *s);

Set `key` in part `part` of `self` to have `s` as a string value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`s` : | a string value

### tp_message_set_string_printf ()

    void                tp_message_set_string_printf        (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             const gchar *fmt,
                                                             ...);

Set `key` in part `part` of `self` to have a string value constructed from a printf-style format string.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`fmt` : | a printf-style format string for the string value
`...` : | arguments for the format string

### tp_message_set_uint16()

    #define             tp_message_set_uint16(s, p, k, u)

Set `key` in part `part` of `self` to have `u` as an unsigned integer value.

`since` 0.7.UNRELEASED

`s` : | a message
`p` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`k` : | a key in the mapping representing the part
`u` : | an unsigned integer value

### tp_message_set_uint32 ()

    void                tp_message_set_uint32               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint32 u);

Set `key` in part `part` of `self` to have `u` as an unsigned integer value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`u` : | an unsigned integer value

### tp_message_set_uint64 ()

    void                tp_message_set_uint64               (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             guint64 u);

Set `key` in part `part` of `self` to have `u` as an unsigned integer value.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`u` : | an unsigned integer value

### tp_message_take_message ()

    void                tp_message_take_message             (TpMessage *self,
                                                             guint part,
                                                             const gchar *key,
                                                             TpMessage *message);

Set `key` in part `part` of `self` to have `message` as an aa{sv} value (that is, an array of Message_Part), and take ownership of `message`. The caller should not use `message` after passing it to this function. All handle references owned by `message` will subsequently belong to and be released with `self`.

`since` 0.7.UNRELEASED

`self` : | a message
`part` : | a part number, which must be strictly less than the number returned by `tp_message_count_parts()`
`key` : | a key in the mapping representing the part
`message` : | another (distinct) message created for the same TpBaseConnection

### TpMessageMixin

    typedef struct {
    } TpMessageMixin;

Structure to be included in the instance structure of objects that use this mixin. Initialize it with `tp_message_mixin_init()`.

There are no public fields.

`since` 0.7.UNRELEASED

### TpMessageMixinSendImpl ()

    void                (*TpMessageMixinSendImpl)           (GObject *object,
                                                             TpMessage *message,
                                                             TpMessageSendingFlags flags);

Signature of a virtual method which may be implemented to allow messages to be sent. It must arrange for `tp_message_mixin_sent()` to be called when the message has submitted or when message submission has failed.

`object` : | An instance of the implementation that uses this mixin
`message` : | An outgoing message
`flags` : | flags with which to send the message

### tp_message_mixin_finalize ()

    void                tp_message_mixin_finalize           (GObject *obj);

Free resources held by the text mixin.

`since` 0.7.UNRELEASED

`obj` : | An object with this mixin.

### tp_message_mixin_implement_sending ()

    void                tp_message_mixin_implement_sending  (GObject *object,
                                                             TpMessageMixinSendImpl send,
                                                             guint n_types,
                                                             const TpChannelTextMessageType *types,
                                                             TpMessagePartSupportFlags message_part_support_flags,
                                                             TpDeliveryReportingSupportFlags delivery_reporting_support_flags,
                                                             const gchar * const *supported_content_types);

Set the callback used to implement SendMessage, and the types of message that can be sent. This must be called from the init, constructor or constructed callback, after `tp_message_mixin_init()`, and may only be called once per object.

`since` 0.7.UNRELEASED

`object` : | An instance of the implementation that uses this mixin
`send` : | An implementation of `SendMessage()`
`n_types` : | Number of supported message types
`types` : | `n_types` supported message types
`message_part_support_flags` : | Flags indicating what message part structures are supported
`delivery_reporting_support_flags` : | Flags indicating what kind of delivery reports are supported
`supported_content_types` : | The supported content types

### tp_message_mixin_init ()

    void                tp_message_mixin_init               (GObject *obj,
                                                             gsize offset,
                                                             TpBaseConnection *connection);

Initialize the mixin. Should be called from the implementation's instance init function or constructor like so:

    tp_message_mixin_init ((GObject *) self,
        G_STRUCT_OFFSET (SomeObject, message_mixin),
        self->connection);

`since` 0.7.UNRELEASED

`obj` : | An instance of the implementation that uses this mixin
`offset` : | The byte offset of the TpMessageMixin within the object structure
`connection` : | A TpBaseConnection

### tp_message_mixin_init_dbus_properties ()

    void                tp_message_mixin_init_dbus_properties
                                                            (GObjectClass *cls);

Set up a TpDBusPropertiesMixinClass to use this mixin's implementation of the Messages interface's properties.

This uses `tp_message_mixin_get_dbus_property()` as the property getter and sets a list of the supported properties for it.

`cls` : | The class of an object with this mixin

### tp_message_mixin_messages_iface_init ()

    void                tp_message_mixin_messages_iface_init
                                                            (gpointer g_iface,
                                                             gpointer iface_data);

Fill in this mixin's Messages method implementations in the given interface vtable.

`since` 0.7.UNRELEASED

`g_iface` : | A pointer to the TpSvcChannelInterfaceMessagesClass in an object class
`iface_data` : | Ignored

### tp_message_mixin_get_dbus_property ()

    void                tp_message_mixin_get_dbus_property  (GObject *object,
                                                             GQuark interface,
                                                             GQuark name,
                                                             GValue *value,
                                                             gpointer unused);

An implementation of TpDBusPropertiesMixinGetter which assumes that the `object` has the messages mixin. It can only be used for the Messages interface.

`object` : | An object with this mixin
`interface` : | Must be `TP_IFACE_QUARK_CHANNEL_INTERFACE_MESSAGES`
`name` : | A quark representing the D-Bus property name, either "PendingMessages", "SupportedContentTypes" or "MessagePartSupportFlags"
`value` : | A GValue pre-initialized to the right type, into which to put the value
`unused` : | Ignored

### tp_message_mixin_sent ()

    void                tp_message_mixin_sent               (GObject *object,
                                                             TpMessage *message,
                                                             TpMessageSendingFlags flags,
                                                             const gchar *token,
                                                             const GError *error);

Indicate to the message mixin that message submission to the IM server has succeeded or failed.

After this function is called, `message` will have been freed, and must not be dereferenced.

`since` 0.7.UNRELEASED

`object` : | An object implementing the Text and Messages interfaces with this mixin
`message` : | The outgoing message
`flags` : | The flags used when sending the message, which may be a subset of those passed to the TpMessageMixinSendImpl implementation if not all are supported, or `0` on error.
`token` : | A token representing the sent message (see the Telepathy D-Bus API specification), or an empty string if no suitable identifier is available, or `NULL` on error
`error` : | `NULL` on success, or the error with which message submission failed

### tp_message_mixin_set_rescued ()

    void                tp_message_mixin_set_rescued        (GObject *obj);

Mark all pending messages as having been "rescued" from a channel that previously closed.

`obj` : | An object with this mixin

### tp_message_mixin_take_received ()

    guint               tp_message_mixin_take_received      (GObject *object,
                                                             TpMessage *message);

Receive a message into the pending messages queue, where it will stay until acknowledged, and emit the Received and ReceivedMessage signals. Also emit the SendError signal if the message is a failed delivery report.

`object` : | a channel with this mixin
`message` : | the message. Its ownership is claimed by the message mixin, so it must no longer be modified or freed
Returns : | the message ID `since` 0.7.UNRELEASED

### tp_message_mixin_has_pending_messages ()

    gboolean            tp_message_mixin_has_pending_messages
                                                            (GObject *object,
                                                             TpHandle *first_sender);

Return whether the channel `obj` has unacknowledged messages. If so, and `first_sender` is not `NULL`, the handle of the sender of the first message is placed in it, without incrementing the handle's reference count.

`object` : | An object with this mixin
`first_sender` : | If not `NULL`, used to store the sender of the oldest pending message
Returns : | `TRUE` if there are pending messages

### tp_message_mixin_clear ()

    void                tp_message_mixin_clear              (GObject *obj);

Clear the pending message queue, deleting all messages without emitting PendingMessagesRemoved.

`obj` : | An object with this mixin

### tp_message_mixin_text_iface_init ()

    void                tp_message_mixin_text_iface_init    (gpointer g_iface,
                                                             gpointer iface_data);

Fill in this mixin's Text method implementations in the given interface vtable.

`since` 0.7.UNRELEASED

`g_iface` : | A pointer to the TpSvcChannelTypeTextClass in an object class
`iface_data` : | Ignored

## See Also

TpSvcChannelTypeText, TpSvcChannelInterfaceMessages, TpDBusPropertiesMixin