Added protocols for the Disk Device API.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@2619 a95241bf-73f2-0310-859d-f6bbb57e9c96

docs/develop/servers/registrar/Protocols

@@ -46,10 +46,12 @@ fields:
 General Requests
 ----------------
 
-getting the messengers for MIME and clipboard management respectively
+getting the messengers for MIME, clipboard and disk device management
+respectively
 
 target:		registrar app looper (preferred handler)
 message:	B_REG_GET_MIME_MESSENGER/B_REG_GET_CLIPBOARD_MESSENGER
+			/B_REG_GET_DISK_DEVICE_MESSENGER
 reply:		standard success
 			"messenger": B_MESSENGER_TYPE
 on error:	- B_NO_REPLY (fatal)
@@ -866,3 +868,148 @@ reply fields:
 
 -----------------------------------------------------------------------
 
+
+Disk Device Requests
+--------------------
+
+get next disk device
+
+target:		disk device manager
+message:	B_REG_NEXT_DISK_DEVICE
+			"cookie":				B_INT32_TYPE
+reply:		standard success
+			"device":				B_MESSAGE_TYPE
+			"cookie":				B_INT32_TYPE
+on error:	- B_NO_REPLY (fatal)
+			- standard error
+
+message fields:
+- "cookie": An iteration cookie. Initially 0.
+
+reply fields:
+- "device": Archived BDiskDevice info.
+- "cookie": Next value for the iteration cookie.
+
+error reply fields:
+- "error":
+  - B_BAD_VALUE: A request message field is missing or contains an
+    invalid value.
+  - B_ENTRY_NOT_FOUND: Iteration finished.
+  - ...
+
+-----------------------------------------------------------------------
+
+get disk device
+
+target:		disk device manager
+message:	B_REG_GET_DISK_DEVICE
+			"device_id":			B_INT32_TYPE
+			| "session_id":			B_INT32_TYPE
+			| "partition_id":		B_INT32_TYPE
+reply:		standard success
+			"device":				B_MESSAGE_TYPE
+on error:	- B_NO_REPLY (fatal)
+			- standard error
+
+message fields:
+- "device_id": ID of the device to be retrieved.
+- "session_id": ID of session whose device shall be retrieved.
+- "partition_id": ID of partition whose device shall be retrieved.
+
+reply fields:
+- "device": Archived BDiskDevice info.
+
+error reply fields:
+- "error":
+  - B_BAD_VALUE: A request message field is missing or contains an
+    invalid value.
+  - B_ENTRY_NOT_FOUND: A device/session/partition with that ID could not
+  	be found.
+  - ...
+
+-----------------------------------------------------------------------
+
+update disk device
+
+target:		disk device manager
+message:	B_REG_UPDATE_DISK_DEVICE
+			"device_id":			B_INT32_TYPE
+			| "session_id":			B_INT32_TYPE
+			| "partition_id":		B_INT32_TYPE
+			"change_counter":		B_INT32_TYPE
+			"update_policy":		B_INT32_TYPE
+reply:		standard success
+			"up_to_date":			B_BOOLEAN_TYPE
+			[ "device":				B_MESSAGE_TYPE ]
+on error:	- B_NO_REPLY (fatal)
+			- standard error
+
+message fields:
+- "device_id": ID of the device to be retrieved.
+- "session_id": ID of session whose device shall be retrieved.
+- "partition_id": ID of partition whose device shall be retrieved.
+- "change_counter": Change counter of the object in question.
+- "update_policy": (uint32)
+  B_REG_DEVICE_UPDATE_CHECK: Check only, if the object is up to date.
+  B_REG_DEVICE_UPDATE_CHANGED: Update only, if the object has changed.
+  B_REG_DEVICE_UPDATE_DEVICE_CHANGED: Update, if the device has changed, even
+									  if the partition/session has not.
+  The latter two have the same semantics, if the object is a device.
+
+reply fields:
+- "up_to_date": true, if the object (and for
+  B_REG_DEVICE_UPDATE_DEVICE_CHANGED also the device) is already up to date,
+  false otherwise.
+- "device": Archived BDiskDevice info.
+
+error reply fields:
+- "error":
+  - B_BAD_VALUE: A request message field is missing or contains an
+    invalid value.
+  - B_ENTRY_NOT_FOUND: A device/session/partition with that ID could not
+  	be found.
+  - ...
+
+-----------------------------------------------------------------------
+
+start disk device watching
+
+target:		disk device manager
+message:	B_REG_DEVICE_START_WATCHING
+			"target":	B_MESSENGER_TYPE
+			"events":	B_INT32_TYPE
+reply:		standard success
+on error:	- B_NO_REPLY (fatal)
+			- standard error
+
+message fields:
+- "target": The target the event messages shall be sent to.
+- "events": Specifies the events the caller is interested in (uint32).
+
+error reply fields:
+- "error":
+  - B_BAD_VALUE: A request message field is missing or contains an
+    invalid value.
+  - ...
+
+-----------------------------------------------------------------------
+
+stop disk device watching
+
+target:		disk device manager
+message:	B_REG_DEVICE_STOP_WATCHING
+			"target":	B_MESSENGER_TYPE
+reply:		standard success
+on error:	- B_NO_REPLY (fatal)
+			- standard error
+
+message fields:
+- "target": The target that shall not longer receive any event messages.
+
+error reply fields:
+- "error":
+  - B_BAD_VALUE: A request message field is missing or contains an
+    invalid value.
+  - ...
+
+-----------------------------------------------------------------------