* the terms of the GNU Lesser General Public License as published by the
* Free Software Foundation; either version 2.1 of the License, or (at
* your option) any later version.
+ *
+ * "Everything should be made as simple as possible, but not simpler."
+ * -- Albert Einstein
*/
#ifndef _KDBUS_H_
* cookie identifies the message and the
* respective reply carries the cookie
* in cookie_reply
+ * @KDBUS_MSG_FLAGS_SYNC_REPLY: Wait for destination connection to
+ * reply to this message. The
+ * KDBUS_CMD_MSG_SEND ioctl() will block
+ * until the reply is received, and
+ * offset_reply in struct kdbus_msg will
+ * yield the offset in the sender's pool
+ * where the reply can be found.
+ * This flag is only valid if
+ * @KDBUS_MSG_FLAGS_EXPECT_REPLY is set as
+ * well.
* @KDBUS_MSG_FLAGS_NO_AUTO_START: Do not start a service, if the addressed
* name is not currently active
*/
enum kdbus_msg_flags {
KDBUS_MSG_FLAGS_EXPECT_REPLY = 1 << 0,
- KDBUS_MSG_FLAGS_NO_AUTO_START = 1 << 1,
+ KDBUS_MSG_FLAGS_SYNC_REPLY = 1 << 1,
+ KDBUS_MSG_FLAGS_NO_AUTO_START = 1 << 2,
};
/**
* struct kdbus_msg - the representation of a kdbus message
* @size: Total size of the message
* @flags: Message flags (KDBUS_MSG_FLAGS_*)
+ * @priority: Message queue priority value
* @dst_id: 64-bit ID of the destination connection
* @src_id: 64-bit ID of the source connection
* @payload_type: Payload type (KDBUS_PAYLOAD_*)
* @cookie_reply: A reply to the requesting message with the same
* cookie. The requesting connection can match its
* request and the reply with this value
+ * @offset_reply: If KDBUS_MSG_FLAGS_WAIT_FOR_REPLY, this field will
+ * contain the offset in the sender's pool where the
+ * reply is stored.
* @items: A list of kdbus_items containing the message payload
*/
struct kdbus_msg {
__u64 size;
__u64 flags;
+ __s64 priority;
__u64 dst_id;
__u64 src_id;
__u64 payload_type;
union {
__u64 timeout_ns;
__u64 cookie_reply;
+ __u64 offset_reply;
};
struct kdbus_item items[0];
} __attribute__((aligned(8)));
+/**
+ * enum kdbus_recv_flags - flags for de-queuing messages
+ * @KDBUS_RECV_PEEK: Return the next queued message without
+ * actually de-queuing it, and without installing
+ * any file descriptors or other resources. It is
+ * usually used to determine the activating
+ * connection of a bus name.
+ * @KDBUS_RECV_DROP: Drop and free the next queued message and all
+ * its resources without actually receiving it.
+ * @KDBUS_RECV_USE_PRIORITY: Only de-queue messages with the specified or
+ * higher priority (lowest values); if not set,
+ * the priority value is ignored.
+ */
+enum kdbus_recv_flags {
+ KDBUS_RECV_PEEK = 1 << 0,
+ KDBUS_RECV_DROP = 1 << 1,
+ KDBUS_RECV_USE_PRIORITY = 1 << 2,
+};
+
+/**
+ * struct kdbus_cmd_recv - struct to de-queue a buffered message
+ * @flags: KDBUS_RECV_* flags
+ * @priority: Minimum priority of the messages to de-queue. Lowest
+ * values have the highest priority.
+ * @offset: Returned offset in the pool where the message is
+ * stored. The user must use KDBUS_CMD_FREE to free
+ * the allocated memory.
+ *
+ * This struct is used with the KDBUS_CMD_MSG_RECV ioctl.
+ */
+struct kdbus_cmd_recv {
+ __u64 flags;
+ __s64 priority;
+ __u64 offset;
+} __attribute__((aligned(8)));
+
/**
* enum kdbus_policy_access_type - permissions of a policy record
* @_KDBUS_POLICY_ACCESS_NULL: Uninitialized/invalid
* @id128: Unique 128-bit ID of the bus (kernel → userspace)
* @items: A list of items
*
- * This struct is used with the KDBUS_CMD_HELLO ioctl. See the ioctl
- * documentation for more information.
+ * This struct is used with the KDBUS_CMD_HELLO ioctl.
*/
struct kdbus_cmd_hello {
__u64 size;
* placed in the receiver's pool.
* @KDBUS_CMD_FREE: Release the allocated memory in the receiver's
* pool.
- * @KDBUS_CMD_DROP: Drop and free the next queued message and all
- * its ressources without actually receiveing it.
- * @KDBUS_CMD_SRC: Query the sender's connection ID of the next
- * queued message, used to determine the activating
- * connection of a bus name.
* @KDBUS_CMD_NAME_ACQUIRE: Request a well-known bus name to associate with
* the connection. Well-known names are used to
* address a peer on the bus.
KDBUS_CMD_BYEBYE = _IO (KDBUS_IOC_MAGIC, 0x31),
KDBUS_CMD_MSG_SEND = _IOW (KDBUS_IOC_MAGIC, 0x40, struct kdbus_msg),
- KDBUS_CMD_MSG_RECV = _IOR (KDBUS_IOC_MAGIC, 0x41, __u64 *),
+ KDBUS_CMD_MSG_RECV = _IOWR(KDBUS_IOC_MAGIC, 0x41, struct kdbus_cmd_recv),
KDBUS_CMD_FREE = _IOW (KDBUS_IOC_MAGIC, 0x42, __u64 *),
- KDBUS_CMD_MSG_DROP = _IO (KDBUS_IOC_MAGIC, 0x43),
- KDBUS_CMD_MSG_SRC = _IOR (KDBUS_IOC_MAGIC, 0x44, __u64 *),
KDBUS_CMD_NAME_ACQUIRE = _IOWR(KDBUS_IOC_MAGIC, 0x50, struct kdbus_cmd_name),
KDBUS_CMD_NAME_RELEASE = _IOW (KDBUS_IOC_MAGIC, 0x51, struct kdbus_cmd_name),
* @ENOENT: The name to query information about is currently not on
* the bus.
* @ENOMEM: Out of memory.
+ * @ENOMSG: The queue is not empty, but no message with a matching
+ * priority is currently queued.
* @ENOSYS: The requested functionality is not available.
* @ENOTSUPP: The feature negotiation failed, a not supported feature
* was requested, or an unknown item type was received.
~ianmdlvl / elogind.git / blobdiff