Permalink
Cannot retrieve contributors at this time
Name already in use
A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
glibc/sysdeps/unix/sysv/linux/sigstack.c
Go to fileThis commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
66 lines (53 sloc)
2 KB
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
/* Emulate sigstack function using sigaltstack. | |
Copyright (C) 1998-2016 Free Software Foundation, Inc. | |
This file is part of the GNU C Library. | |
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. | |
The GNU C Library is free software; you can redistribute it and/or | |
modify it under the terms of the GNU Lesser General Public | |
License as published by the Free Software Foundation; either | |
version 2.1 of the License, or (at your option) any later version. | |
The GNU C Library is distributed in the hope that it will be useful, | |
but WITHOUT ANY WARRANTY; without even the implied warranty of | |
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
Lesser General Public License for more details. | |
You should have received a copy of the GNU Lesser General Public | |
License along with the GNU C Library; if not, see | |
<http://www.gnu.org/licenses/>. */ | |
#include <signal.h> | |
#include <stddef.h> | |
#include <sys/syscall.h> | |
#ifdef __NR_sigaltstack | |
int | |
sigstack (struct sigstack *ss, struct sigstack *oss) | |
{ | |
stack_t sas; | |
stack_t *sasp = NULL; | |
stack_t osas; | |
stack_t *osasp = oss == NULL ? NULL : &osas; | |
int result; | |
if (ss != NULL) | |
{ | |
/* We have to convert the information. */ | |
sas.ss_sp = ss->ss_sp; | |
sas.ss_flags = ss->ss_onstack ? SS_ONSTACK : 0; | |
/* For the size of the stack we have no value we can pass to the | |
kernel. This is why this function should not be used. We simply | |
assume that all the memory down to address zero (in case the stack | |
grows down) is available. */ | |
sas.ss_size = ss->ss_sp - NULL; | |
sasp = &sas; | |
} | |
/* Call the kernel. */ | |
result = __sigaltstack (sasp, osasp); | |
/* Convert the result, if wanted and possible. */ | |
if (result == 0 && oss != NULL) | |
{ | |
oss->ss_sp = osas.ss_sp; | |
oss->ss_onstack = (osas.ss_flags & SS_ONSTACK) != 0; | |
} | |
return result; | |
} | |
link_warning (sigstack, "the `sigstack' function is dangerous. `sigaltstack' should be used instead.") | |
#else | |
# include <signal/sigstack.c> | |
#endif |