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/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
# ifdef WITH_BACKTRACE
static void
stack_dumper(int sig, siginfo_t *info, void *ucontext)
{
(void) sig;
(void) info;
libtest_print_backtrace(stderr, "crashed at ", " by ", 0u, NULL, ucontext);
}
static stack_t ss;
static size_t have_ss = 0u;
static void
create_altstack(void)
{
if (have_ss++)
return;
ss.ss_sp = libtest_real_mmap(NULL, (size_t)SIGSTKSZ, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
assert(ss.ss_sp != MAP_FAILED);
ss.ss_size = (size_t)SIGSTKSZ;
ss.ss_flags = 0;
assert(!sigaltstack(&ss, NULL));
}
static void
destroy_altstack(void)
{
if (--have_ss)
return;
assert(!libtest_real_munmap(ss.ss_sp, ss.ss_size));
}
void
libtest_stack_on_signal(int signo, struct sigaction *old_out)
{
struct sigaction sa;
create_altstack();
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = &stack_dumper;
sa.sa_flags = (int)(SA_RESETHAND | SA_SIGINFO);
if (have_ss)
sa.sa_flags |= SA_ONSTACK;
sigfillset(&sa.sa_mask);
assert(!sigaction(signo, &sa, old_out));
}
void
libtest_stop_stack_on_signal(int signo, const struct sigaction *old)
{
struct sigaction sa;
if (!old) {
memset(&sa, 0, sizeof(sa));
sa.sa_handler = SIG_DFL;
old = &sa;
}
assert(!sigaction(signo, old, NULL));
destroy_altstack();
}
#else
void
libtest_stack_on_signal(int signo, struct sigaction *old_out)
{
(void) signo;
(void) old_out;
}
void
libtest_stop_stack_on_signal(int signo, const struct sigaction *old)
{
(void) signo;
(void) old;
}
# endif
#else
CONST int
main(void)
{
/* How would one even test this, and what would be the point? */
return 0;
}
#endif
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