1 /* Copyright (C) 1995,1996, 1997 Free Software Foundation, Inc.
3 * This program is free software; you can redistribute it and/or modify
4 * it under the terms of the GNU General Public License as published by
5 * the Free Software Foundation; either version 2, or (at your option)
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this software; see the file COPYING. If not, write to
15 * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
16 * Boston, MA 02111-1307 USA
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
21 * The exception is that, if you link the GUILE library with other files
22 * to produce an executable, this does not by itself cause the
23 * resulting executable to be covered by the GNU General Public License.
24 * Your use of that executable is in no way restricted on account of
25 * linking the GUILE library code into it.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
30 * This exception applies only to the code released by the
31 * Free Software Foundation under the name GUILE. If you copy
32 * code from other Free Software Foundation releases into a copy of
33 * GUILE, as the General Public License permits, the exception does
34 * not apply to the code that you add in this way. To avoid misleading
35 * anyone as to the status of such modified files, you must delete
36 * this exception notice from them.
38 * If you write modifications of your own for GUILE, it is your choice
39 * whether to permit this exception to apply to your modifications.
40 * If you do not wish that, delete this exception notice. */
52 * These procedures implement synchronization primitives. Processors
53 * with an atomic test-and-set instruction can use it here (and not
57 static long scm_tc16_arbiter
;
61 prinarb (exp
, port
, pstate
)
64 scm_print_state
*pstate
;
66 scm_puts ("#<arbiter ", port
);
67 if (SCM_CAR (exp
) & (1L << 16))
68 scm_puts ("locked ", port
);
69 scm_iprin1 (SCM_CDR (exp
), port
, pstate
);
74 static scm_smobfuns arbsmob
=
76 scm_markcdr
, scm_free0
, prinarb
, 0
79 SCM_PROC(s_make_arbiter
, "make-arbiter", 1, 0, 0, scm_make_arbiter
);
82 scm_make_arbiter (name
)
89 SCM_SETCAR (z
, scm_tc16_arbiter
);
94 SCM_PROC(s_try_arbiter
, "try-arbiter", 1, 0, 0, scm_try_arbiter
);
100 SCM_ASSERT ((SCM_TYP16 (arb
) == scm_tc16_arbiter
), arb
, SCM_ARG1
, s_try_arbiter
);
102 if (SCM_CAR (arb
) & (1L << 16))
106 SCM_SETCAR (arb
, scm_tc16_arbiter
| (1L << 16));
114 SCM_PROC(s_release_arbiter
, "release-arbiter", 1, 0, 0, scm_release_arbiter
);
117 scm_release_arbiter (arb
)
120 SCM_ASSERT ((SCM_TYP16 (arb
) == scm_tc16_arbiter
), arb
, SCM_ARG1
, s_release_arbiter
);
121 if (!(SCM_CAR (arb
) & (1L << 16)))
123 SCM_SETCAR (arb
, scm_tc16_arbiter
);
132 scm_tc16_arbiter
= scm_newsmob (&arbsmob
);
133 #include "arbiters.x"