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 33 int __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 47 int sigwait(const sigset_t *set, int *sig) 48 { 49 int ret; 50 /* use a union to get rid of aliasing warnings */ 51 union { 52 unsigned long kernel_sigset[2]; 53 sigset_t dummy_sigset; 54 } u; 55 56 u.kernel_sigset[0] = *set; 57 u.kernel_sigset[1] = 0; /* no real-time signals supported ? */ 58 for (;;) 59 { 60 /* __rt_sigtimedwait can return EAGAIN or EINTR, we need to loop 61 * around them since sigwait is only allowed to return EINVAL 62 */ 63 ret = __rt_sigtimedwait ( &u.dummy_sigset, NULL, NULL, sizeof(u.kernel_sigset)); 64 if (ret >= 0) 65 break; 66 67 if (errno != EAGAIN && errno != EINTR) 68 return errno; 69 } 70 71 *sig = ret; 72 return 0; 73 } 74 75