1 ------------------------------------------------------------------------------
3 -- GNU ADA RUN-TIME LIBRARY (GNARL) COMPONENTS --
5 -- S Y S T E M . T A S K I N G . P R O T E C T E D _ O B J E C T S --
9 -- Copyright (C) 1991-1994, Florida State University --
10 -- Copyright (C) 1995-2003, Ada Core Technologies --
12 -- GNARL is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNARL is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNARL; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNARL was developed by the GNARL team at Florida State University. --
31 -- Extensive contributions were provided by Ada Core Technologies, Inc. --
33 ------------------------------------------------------------------------------
36 -- Turn off polling, we do not want ATC polling to take place during
37 -- tasking operations. It causes infinite loops and other problems.
39 with System.Task_Primitives.Operations;
40 -- used for Write_Lock
43 with System.Parameters;
44 -- used for Runtime_Traces
47 -- used for Send_Trace_Info
49 package body System.Tasking.Protected_Objects is
51 use System.Task_Primitives.Operations;
54 -------------------------
55 -- Finalize_Protection --
56 -------------------------
58 procedure Finalize_Protection (Object : in out Protection) is
60 Finalize_Lock (Object.L'Unrestricted_Access);
61 end Finalize_Protection;
63 ---------------------------
64 -- Initialize_Protection --
65 ---------------------------
67 procedure Initialize_Protection
68 (Object : Protection_Access;
69 Ceiling_Priority : Integer)
71 Init_Priority : Integer := Ceiling_Priority;
73 if Init_Priority = Unspecified_Priority then
74 Init_Priority := System.Priority'Last;
77 Initialize_Lock (Init_Priority, Object.L'Access);
78 Object.Ceiling := System.Any_Priority (Init_Priority);
79 end Initialize_Protection;
85 procedure Lock (Object : Protection_Access) is
86 Ceiling_Violation : Boolean;
88 -- The lock is made without defering abortion.
90 -- Therefore the abortion has to be deferred before calling this
91 -- routine. This means that the compiler has to generate a Defer_Abort
92 -- call before the call to Lock.
94 -- The caller is responsible for undeferring abortion, and compiler
95 -- generated calls must be protected with cleanup handlers to ensure
96 -- that abortion is undeferred in all cases.
98 Write_Lock (Object.L'Access, Ceiling_Violation);
100 if Parameters.Runtime_Traces then
101 Send_Trace_Info (PO_Lock);
104 if Ceiling_Violation then
113 procedure Lock_Read_Only (Object : Protection_Access) is
114 Ceiling_Violation : Boolean;
116 Read_Lock (Object.L'Access, Ceiling_Violation);
118 if Parameters.Runtime_Traces then
119 Send_Trace_Info (PO_Lock);
122 if Ceiling_Violation then
131 procedure Unlock (Object : Protection_Access) is
133 Unlock (Object.L'Access);
135 if Parameters.Runtime_Traces then
136 Send_Trace_Info (PO_Unlock);
140 end System.Tasking.Protected_Objects;