projects / apple / libplatform.git / blame
| Commit | Line | Data |
|---|---|---|
| ada7c492 A |
1 | /* |
| 2 | * Copyright (c) 2007, 2009 Apple Inc. All rights reserved. | |
| 3 | * | |
| 4 | * @APPLE_LICENSE_HEADER_START@ | |
| 5 | * | |
| 6 | * This file contains Original Code and/or Modifications of Original Code | |
| 7 | * as defined in and that are subject to the Apple Public Source License | |
| 8 | * Version 2.0 (the 'License'). You may not use this file except in | |
| 9 | * compliance with the License. Please obtain a copy of the License at | |
| 10 | * http://www.opensource.apple.com/apsl/ and read it before using this | |
| 11 | * file. | |
| 12 | * | |
| 13 | * The Original Code and all software distributed under the License are | |
| 14 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER | |
| 15 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, | |
| 16 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, | |
| 17 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. | |
| 18 | * Please see the License for the specific language governing rights and | |
| 19 | * limitations under the License. | |
| 20 | * | |
| 21 | * @APPLE_LICENSE_HEADER_END@ | |
| 22 | */ | |
| 23 | ||
| 24 | /* | |
| 25 | * Copyright (c) 2001 Daniel M. Eischen <deischen@freebsd.org> | |
| 26 | * All rights reserved. | |
| 27 | * | |
| 28 | * Redistribution and use in source and binary forms, with or without | |
| 29 | * modification, are permitted provided that the following conditions | |
| 30 | * are met: | |
| 31 | * 1. Redistributions of source code must retain the above copyright | |
| 32 | * notice, this list of conditions and the following disclaimer. | |
| 33 | * 2. Neither the name of the author nor the names of its contributors | |
| 34 | * may be used to endorse or promote products derived from this software | |
| 35 | * without specific prior written permission. | |
| 36 | * | |
| 37 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND | |
| 38 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 39 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 40 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE | |
| 41 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| 42 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| 43 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 44 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
| 45 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
| 46 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
| 47 | * SUCH DAMAGE. | |
| 48 | */ | |
| 49 | ||
| 50 | #define _XOPEN_SOURCE 600L | |
| 51 | #include <ucontext.h> | |
| 52 | #include <errno.h> | |
| 53 | ||
| 54 | #if defined(__x86_64__) || defined(__i386__) | |
| 55 | #pragma clang diagnostic ignored "-Wdeprecated-declarations" | |
| 56 | ||
| 57 | #include <sys/param.h> | |
| 58 | #include <sys/signal.h> | |
| 59 | #include <stddef.h> | |
| 60 | ||
| 61 | #define uc_flags uc_onstack | |
| 62 | #define UCF_SWAPPED 0x80000000 | |
| 63 | ||
| 64 | int | |
| 65 | swapcontext(ucontext_t *oucp, const ucontext_t *ucp) | |
| 66 | { | |
| 67 | int ret; | |
| 68 | ||
| 69 | if ((oucp == NULL) || (ucp == NULL)) { | |
| 70 | errno = EINVAL; | |
| 71 | return (-1); | |
| 72 | } | |
| 73 | oucp->uc_flags &= ~UCF_SWAPPED; | |
| 74 | ret = getcontext(oucp); | |
| 75 | if ((ret == 0) && !(oucp->uc_flags & UCF_SWAPPED)) { | |
| 76 | oucp->uc_flags |= UCF_SWAPPED; | |
| 77 | ret = setcontext(ucp); | |
| 78 | } | |
| 79 | asm(""); // Prevent tailcall <rdar://problem/12581792> | |
| 80 | return (ret); | |
| 81 | } | |
| 82 | ||
| 83 | #else | |
| 84 | ||
| 85 | int | |
| 86 | swapcontext(ucontext_t *oucp, const ucontext_t *ucp) | |
| 87 | { | |
| 88 | errno = ENOTSUP; | |
| 89 | return -1; | |
| 90 | } | |
| 91 | ||
| 92 | #endif |