Package Name: system.tasking.entry_calls
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-- GNU ADA RUNTIME LIBRARY (GNARL) COMPONENTS --
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-- S Y S T E M . T A S K I N G . E N T R Y _ C A L L S --
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package System.Tasking.Entry_Calls is
procedure Lock_Server
(Entry_Call : Entry_Call_Link;
No_Server : out Boolean);
-- This locks the server targeted by Entry_Call, returning
-- No_Server=True if no server is currently targeted.
-- This may be a task or a protected object, depending on the
-- target of the original call or any subsequent requeues.
-- It will fail if there is no such target.
-- This routine is needed because the field specifying the server
-- for this call must be protected by the server's mutex. If it were
-- protected by the caller's mutex, accessing the server's queues would
-- require locking the caller to get the server, locking the server,
-- and then accessing the queues. This involves holding two ATCB
-- locks at once, something which we can guarantee that it will always
-- be done in the same order, or locking a protected object while we
-- hold an ATCB lock, something which is not permitted. Since
-- the server cannot be obtained reliably, it must be obtained unreliably
-- and then checked again once it has been locked.
procedure Unlock_Server (Entry_Call : Entry_Call_Link);
-- Unlock the server targeted by Entry_Call. The server must
-- be locked before calling this.
procedure Unlock_And_Update_Server (Entry_Call : Entry_Call_Link);
-- Similar to Unlock_Server, but services entry calls if the
-- server is a protected object.
procedure Wait_For_Completion (Entry_Call : Entry_Call_Link);
-- This procedure suspends the calling task until the specified entry
-- call has either been completed or cancelled. It performs other
-- operations required of suspended tasks, such as performing
-- dynamic priority changes. On exit, the call will not be queued.
-- This waits for calls on task or protected entries.
-- Abortion must be deferred when calling this procedure.
procedure Wait_Until_Abortable (Caller : Task_ID; Call : Entry_Call_Link);
-- This procedure suspends the calling task until the specified entry
-- call is queued abortably or completes.
-- Abortion must be deferred when calling this procedure.
end System.Tasking.Entry_Calls;