diff options
author | deischen <deischen@FreeBSD.org> | 2002-01-10 02:40:59 +0000 |
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committer | deischen <deischen@FreeBSD.org> | 2002-01-10 02:40:59 +0000 |
commit | e1f74be694147bb02870412a7cb3af53ece7abca (patch) | |
tree | 8750e6ef947fb24d389f0ee38142a07bce7ca69d /lib/libc/gen/swapcontext.c | |
parent | b11ad1474409669c5f7ff5cf0ea388966e0f1780 (diff) | |
download | FreeBSD-src-e1f74be694147bb02870412a7cb3af53ece7abca.zip FreeBSD-src-e1f74be694147bb02870412a7cb3af53ece7abca.tar.gz |
Add getcontext, setcontext, makecontext, and swapcontext. These
functions are defined in SUSv2 and the latest POSIX spec.
Thanks to Bernd Walter <ticso@cicely8.cicely.de> for helping debug my
alpha assembly.
Approved by: -arch
Diffstat (limited to 'lib/libc/gen/swapcontext.c')
-rw-r--r-- | lib/libc/gen/swapcontext.c | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/lib/libc/gen/swapcontext.c b/lib/libc/gen/swapcontext.c new file mode 100644 index 0000000..5434c0f --- /dev/null +++ b/lib/libc/gen/swapcontext.c @@ -0,0 +1,54 @@ +/* + * Copyright (c) 2001 Daniel M. Eischen <deischen@freebsd.org> + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Neither the name of the author nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <errno.h> +#include <signal.h> +#include <ucontext.h> + +__weak_reference(__swapcontext, swapcontext); + +int +__swapcontext(ucontext_t *oucp, const ucontext_t *ucp) +{ + volatile int swapped; + int ret; + + if (oucp == NULL || ucp == NULL) { + errno = EINVAL; + ret = -1; + } + else { + swapped = 0; + if ((ret = getcontext(oucp) == 0) && (swapped == 0)) { + swapped = 1; + ret = setcontext(ucp); + } + } + return (ret); +} |