1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *  * Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *  * Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in
12 *    the documentation and/or other materials provided with the
13 *    distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28#include <errno.h>
29#include <signal.h>
30#include <string.h>
31#include <time.h>
32
33int __rt_sigtimedwait(const sigset_t *uthese, siginfo_t *uinfo, const struct timespec *uts, size_t sigsetsize);
34
35/* ok, this is really subtle: <asm/signal.h> defines sigset_t differently
36 * when you're in the kernel or in the C library.
37 *
38 * in the kernel, this is an array of 2 32-bit unsigned longs
39 * in the C library, this is a single 32-bit unsigned long
40 *
41 * moreover, the kernel implementation of rt_sigtimedwait doesn't
42 * accept anything except kernel-sized signal sets (probably a bug !)
43 *
44 * we thus need to create a fake kernel sigset !!
45 */
46
47int sigwait(const sigset_t *set, int *sig)
48{
49    int  ret;
50#ifdef __mips__
51    /* use a union to get rid of aliasing warnings. On MIPS sigset_t is 128 bits */
52    union {
53      sigset_t       kernel_sigset;
54      sigset_t       dummy_sigset;
55    } u;
56    u.dummy_sigset = *set;
57#else
58    /* use a union to get rid of aliasing warnings */
59    union {
60      unsigned long  kernel_sigset[2];
61      sigset_t       dummy_sigset;
62    } u;
63
64    u.kernel_sigset[0] = *set;
65    u.kernel_sigset[1] = 0;  /* no real-time signals supported ? */
66#endif
67    for (;;)
68    {
69     /* __rt_sigtimedwait can return EAGAIN or EINTR, we need to loop
70      * around them since sigwait is only allowed to return EINVAL
71      */
72      ret = __rt_sigtimedwait ( &u.dummy_sigset, NULL, NULL, sizeof(u.kernel_sigset));
73      if (ret >= 0)
74        break;
75
76      if (errno != EAGAIN && errno != EINTR)
77        return errno;
78    }
79
80    *sig = ret;
81    return 0;
82}
83
84