1*062c5bc4SJason Schmidlapp /*
2*062c5bc4SJason Schmidlapp * pthread_spin_init.c
3*062c5bc4SJason Schmidlapp *
4*062c5bc4SJason Schmidlapp * Description:
5*062c5bc4SJason Schmidlapp * This translation unit implements spin lock primitives.
6*062c5bc4SJason Schmidlapp *
7*062c5bc4SJason Schmidlapp * --------------------------------------------------------------------------
8*062c5bc4SJason Schmidlapp *
9*062c5bc4SJason Schmidlapp * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
10*062c5bc4SJason Schmidlapp * Copyright(C) 2008 Jason Schmidlapp
11*062c5bc4SJason Schmidlapp *
12*062c5bc4SJason Schmidlapp * Contact Email: jschmidlapp@users.sourceforge.net
13*062c5bc4SJason Schmidlapp *
14*062c5bc4SJason Schmidlapp *
15*062c5bc4SJason Schmidlapp * Based upon Pthreads-win32 - POSIX Threads Library for Win32
16*062c5bc4SJason Schmidlapp * Copyright(C) 1998 John E. Bossom
17*062c5bc4SJason Schmidlapp * Copyright(C) 1999,2005 Pthreads-win32 contributors
18*062c5bc4SJason Schmidlapp *
19*062c5bc4SJason Schmidlapp * Contact Email: rpj@callisto.canberra.edu.au
20*062c5bc4SJason Schmidlapp *
21*062c5bc4SJason Schmidlapp * The original list of contributors to the Pthreads-win32 project
22*062c5bc4SJason Schmidlapp * is contained in the file CONTRIBUTORS.ptw32 included with the
23*062c5bc4SJason Schmidlapp * source code distribution. The list can also be seen at the
24*062c5bc4SJason Schmidlapp * following World Wide Web location:
25*062c5bc4SJason Schmidlapp * http://sources.redhat.com/pthreads-win32/contributors.html
26*062c5bc4SJason Schmidlapp *
27*062c5bc4SJason Schmidlapp * This library is free software; you can redistribute it and/or
28*062c5bc4SJason Schmidlapp * modify it under the terms of the GNU Lesser General Public
29*062c5bc4SJason Schmidlapp * License as published by the Free Software Foundation; either
30*062c5bc4SJason Schmidlapp * version 2 of the License, or (at your option) any later version.
31*062c5bc4SJason Schmidlapp *
32*062c5bc4SJason Schmidlapp * This library is distributed in the hope that it will be useful,
33*062c5bc4SJason Schmidlapp * but WITHOUT ANY WARRANTY; without even the implied warranty of
34*062c5bc4SJason Schmidlapp * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
35*062c5bc4SJason Schmidlapp * Lesser General Public License for more details.
36*062c5bc4SJason Schmidlapp *
37*062c5bc4SJason Schmidlapp * You should have received a copy of the GNU Lesser General Public
38*062c5bc4SJason Schmidlapp * License along with this library in the file COPYING.LIB;
39*062c5bc4SJason Schmidlapp * if not, write to the Free Software Foundation, Inc.,
40*062c5bc4SJason Schmidlapp * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
41*062c5bc4SJason Schmidlapp */
42*062c5bc4SJason Schmidlapp
43*062c5bc4SJason Schmidlapp #include <stdlib.h>
44*062c5bc4SJason Schmidlapp
45*062c5bc4SJason Schmidlapp #include "pthread.h"
46*062c5bc4SJason Schmidlapp #include "implement.h"
47*062c5bc4SJason Schmidlapp
48*062c5bc4SJason Schmidlapp
49*062c5bc4SJason Schmidlapp int
pthread_spin_init(pthread_spinlock_t * lock,int pshared)50*062c5bc4SJason Schmidlapp pthread_spin_init (pthread_spinlock_t * lock, int pshared)
51*062c5bc4SJason Schmidlapp {
52*062c5bc4SJason Schmidlapp pthread_spinlock_t s;
53*062c5bc4SJason Schmidlapp int cpus = 0;
54*062c5bc4SJason Schmidlapp int result = 0;
55*062c5bc4SJason Schmidlapp
56*062c5bc4SJason Schmidlapp if (lock == NULL)
57*062c5bc4SJason Schmidlapp {
58*062c5bc4SJason Schmidlapp return EINVAL;
59*062c5bc4SJason Schmidlapp }
60*062c5bc4SJason Schmidlapp
61*062c5bc4SJason Schmidlapp if (0 != pte_getprocessors (&cpus))
62*062c5bc4SJason Schmidlapp {
63*062c5bc4SJason Schmidlapp cpus = 1;
64*062c5bc4SJason Schmidlapp }
65*062c5bc4SJason Schmidlapp
66*062c5bc4SJason Schmidlapp if (cpus > 1)
67*062c5bc4SJason Schmidlapp {
68*062c5bc4SJason Schmidlapp if (pshared == PTHREAD_PROCESS_SHARED)
69*062c5bc4SJason Schmidlapp {
70*062c5bc4SJason Schmidlapp /*
71*062c5bc4SJason Schmidlapp * Creating spinlock that can be shared between
72*062c5bc4SJason Schmidlapp * processes.
73*062c5bc4SJason Schmidlapp */
74*062c5bc4SJason Schmidlapp #if _POSIX_THREAD_PROCESS_SHARED >= 0
75*062c5bc4SJason Schmidlapp
76*062c5bc4SJason Schmidlapp /*
77*062c5bc4SJason Schmidlapp * Not implemented yet.
78*062c5bc4SJason Schmidlapp */
79*062c5bc4SJason Schmidlapp
80*062c5bc4SJason Schmidlapp #error ERROR [__FILE__, line __LINE__]: Process shared spin locks are not supported yet.
81*062c5bc4SJason Schmidlapp
82*062c5bc4SJason Schmidlapp #else
83*062c5bc4SJason Schmidlapp
84*062c5bc4SJason Schmidlapp return ENOSYS;
85*062c5bc4SJason Schmidlapp
86*062c5bc4SJason Schmidlapp #endif /* _POSIX_THREAD_PROCESS_SHARED */
87*062c5bc4SJason Schmidlapp
88*062c5bc4SJason Schmidlapp }
89*062c5bc4SJason Schmidlapp }
90*062c5bc4SJason Schmidlapp
91*062c5bc4SJason Schmidlapp s = (pthread_spinlock_t) calloc (1, sizeof (*s));
92*062c5bc4SJason Schmidlapp
93*062c5bc4SJason Schmidlapp if (s == NULL)
94*062c5bc4SJason Schmidlapp {
95*062c5bc4SJason Schmidlapp return ENOMEM;
96*062c5bc4SJason Schmidlapp }
97*062c5bc4SJason Schmidlapp
98*062c5bc4SJason Schmidlapp if (cpus > 1)
99*062c5bc4SJason Schmidlapp {
100*062c5bc4SJason Schmidlapp s->u.cpus = cpus;
101*062c5bc4SJason Schmidlapp s->interlock = PTE_SPIN_UNLOCKED;
102*062c5bc4SJason Schmidlapp }
103*062c5bc4SJason Schmidlapp else
104*062c5bc4SJason Schmidlapp {
105*062c5bc4SJason Schmidlapp pthread_mutexattr_t ma;
106*062c5bc4SJason Schmidlapp result = pthread_mutexattr_init (&ma);
107*062c5bc4SJason Schmidlapp
108*062c5bc4SJason Schmidlapp if (0 == result)
109*062c5bc4SJason Schmidlapp {
110*062c5bc4SJason Schmidlapp ma->pshared = pshared;
111*062c5bc4SJason Schmidlapp result = pthread_mutex_init (&(s->u.mutex), &ma);
112*062c5bc4SJason Schmidlapp if (0 == result)
113*062c5bc4SJason Schmidlapp {
114*062c5bc4SJason Schmidlapp s->interlock = PTE_SPIN_USE_MUTEX;
115*062c5bc4SJason Schmidlapp }
116*062c5bc4SJason Schmidlapp }
117*062c5bc4SJason Schmidlapp (void) pthread_mutexattr_destroy (&ma);
118*062c5bc4SJason Schmidlapp }
119*062c5bc4SJason Schmidlapp
120*062c5bc4SJason Schmidlapp if (0 == result)
121*062c5bc4SJason Schmidlapp {
122*062c5bc4SJason Schmidlapp *lock = s;
123*062c5bc4SJason Schmidlapp }
124*062c5bc4SJason Schmidlapp else
125*062c5bc4SJason Schmidlapp {
126*062c5bc4SJason Schmidlapp (void) free (s);
127*062c5bc4SJason Schmidlapp *lock = NULL;
128*062c5bc4SJason Schmidlapp }
129*062c5bc4SJason Schmidlapp
130*062c5bc4SJason Schmidlapp return (result);
131*062c5bc4SJason Schmidlapp }
132