1 ------------------------------------------------------------------------------
3 -- GNAT RUN-TIME COMPONENTS --
5 -- A D A . S Y N C H R O N O U S _ B A R R I E R S --
9 -- Copyright (C) 1992-2018, Free Software Foundation, Inc. --
11 -- This specification is derived from the Ada Reference Manual for use with --
12 -- GNAT. The copyright notice above, and the license provisions that follow --
13 -- apply solely to the contents of the part following the private keyword. --
15 -- GNAT is free software; you can redistribute it and/or modify it under --
16 -- terms of the GNU General Public License as published by the Free Soft- --
17 -- ware Foundation; either version 3, or (at your option) any later ver- --
18 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
19 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
20 -- or FITNESS FOR A PARTICULAR PURPOSE. --
22 -- As a special exception under Section 7 of GPL version 3, you are granted --
23 -- additional permissions described in the GCC Runtime Library Exception, --
24 -- version 3.1, as published by the Free Software Foundation. --
26 -- You should have received a copy of the GNU General Public License and --
27 -- a copy of the GCC Runtime Library Exception along with this program; --
28 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
29 -- <http://www.gnu.org/licenses/>. --
31 -- GNAT was originally developed by the GNAT team at New York University. --
32 -- Extensive contributions were provided by Ada Core Technologies Inc. --
34 ------------------------------------------------------------------------------
36 -- This is the body of this package using POSIX barriers
38 with Interfaces
.C
; use Interfaces
.C
;
40 package body Ada
.Synchronous_Barriers
is
46 function pthread_barrier_init
47 (barrier
: not null access pthread_barrier_t
;
48 attr
: System
.Address
:= System
.Null_Address
;
49 count
: unsigned
) return int
;
50 pragma Import
(C
, pthread_barrier_init
, "pthread_barrier_init");
51 -- Initialize barrier with the attributes in attr. The barrier is opened
52 -- when count waiters arrived. If attr is null the default barrier
53 -- attributes are used.
55 function pthread_barrier_destroy
56 (barrier
: not null access pthread_barrier_t
) return int
;
57 pragma Import
(C
, pthread_barrier_destroy
, "pthread_barrier_destroy");
58 -- Destroy a previously dynamically initialized barrier
60 function pthread_barrier_wait
61 (barrier
: not null access pthread_barrier_t
) return int
;
62 pragma Import
(C
, pthread_barrier_wait
, "pthread_barrier_wait");
69 overriding
procedure Finalize
(Barrier
: in out Synchronous_Barrier
) is
72 Result
:= pthread_barrier_destroy
(Barrier
.POSIX_Barrier
'Access);
73 pragma Assert
(Result
= 0);
76 overriding
procedure Initialize
(Barrier
: in out Synchronous_Barrier
) is
81 (barrier
=> Barrier
.POSIX_Barrier
'Access,
82 attr
=> System
.Null_Address
,
83 count
=> unsigned
(Barrier
.Release_Threshold
));
84 pragma Assert
(Result
= 0);
87 ----------------------
88 -- Wait_For_Release --
89 ----------------------
91 procedure Wait_For_Release
92 (The_Barrier
: in out Synchronous_Barrier
;
93 Notified
: out Boolean)
97 PTHREAD_BARRIER_SERIAL_THREAD
: constant := -1;
98 -- Value used to indicate the task which receives the notification for
104 (barrier
=> The_Barrier
.POSIX_Barrier
'Access);
106 (Result
= 0 or else Result
= PTHREAD_BARRIER_SERIAL_THREAD
);
108 Notified
:= (Result
= PTHREAD_BARRIER_SERIAL_THREAD
);
109 end Wait_For_Release
;
111 end Ada
.Synchronous_Barriers
;