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/*
Check that a fault signal handler gets the expected info
*/
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <setjmp.h>
#include "tests/sys_mman.h"
#include <unistd.h>
/* Division by zero triggers a SIGFPE on x86 and x86_64,
but not on the PowerPC architecture.
On ARM-Linux, we do get a SIGFPE, but not from the faulting of a
division instruction (there isn't any such thing) but rather
because the process exits via tgkill, sending itself a SIGFPE.
Hence we get a SIGFPE but the SI_CODE is different from that on
x86/amd64-linux.
*/
#if defined(__powerpc__)
# define DIVISION_BY_ZERO_TRIGGERS_FPE 0
# define DIVISION_BY_ZERO_SI_CODE SI_TKILL
#elif defined(__arm__)
# define DIVISION_BY_ZERO_TRIGGERS_FPE 1
# define DIVISION_BY_ZERO_SI_CODE SI_TKILL
#else
# define DIVISION_BY_ZERO_TRIGGERS_FPE 1
# define DIVISION_BY_ZERO_SI_CODE FPE_INTDIV
#endif
struct test {
void (*test)(void);
int sig;
int code;
volatile void *addr;
};
static const struct test *cur_test;
static int zero();
static jmp_buf escape;
#define BADADDR ((int *)0x1234)
#define FILESIZE (16*1024)
#define MAPSIZE (2*FILESIZE)
static char volatile *volatile mapping;
static int testsig(int sig, int want)
{
if (sig != want) {
fprintf(stderr, " FAIL: expected signal %d, not %d\n", want, sig);
return 0;
}
return 1;
}
static int testcode(int code, int want)
{
if (code != want) {
fprintf(stderr, " FAIL: expected si_code==%d, not %d\n", want, code);
return 0;
}
return 1;
}
static int testaddr(void *addr, volatile void *want)
{
if (addr != want) {
fprintf(stderr, " FAIL: expected si_addr==%p, not %p\n", want, addr);
return 0;
}
return 1;
}
static void handler(int sig, siginfo_t *si, void *uc)
{
int ok = 1;
ok = ok && testsig(sig, cur_test->sig);
ok = ok && testcode(si->si_code, cur_test->code);
if (cur_test->addr)
ok = ok && testaddr(si->si_addr, cur_test->addr);
if (ok)
fprintf(stderr, " PASS\n");
siglongjmp(escape, ok + 1);
}
static void test1(void)
{
*BADADDR = 'x';
}
static void test2()
{
mapping[0] = 'x';
}
static void test3()
{
mapping[FILESIZE+10];
}
static void test4()
{
volatile int v = 44/zero();
(void)v;
#if DIVISION_BY_ZERO_TRIGGERS_FPE == 0
raise(SIGFPE);
#endif
}
int main()
{
int fd, i;
static const int sigs[] = { SIGSEGV, SIGILL, SIGBUS, SIGFPE, SIGTRAP };
struct sigaction sa;
sa.sa_sigaction = handler;
sa.sa_flags = SA_SIGINFO;
sigfillset(&sa.sa_mask);
for(i = 0; i < sizeof(sigs)/sizeof(*sigs); i++)
sigaction(sigs[i], &sa, NULL);
fd = open("faultstatus.tmp", O_CREAT|O_TRUNC|O_EXCL, 0600);
if (fd == -1) {
perror("tmpfile");
exit(1);
}
unlink("faultstatus.tmp");
ftruncate(fd, FILESIZE);
mapping = mmap(0, MAPSIZE, PROT_READ, MAP_PRIVATE, fd, 0);
close(fd);
{
const struct test tests[] = {
#define T(n, sig, code, addr) { test##n, sig, code, addr }
T(1, SIGSEGV, SEGV_MAPERR, BADADDR),
T(2, SIGSEGV, SEGV_ACCERR, mapping),
T(3, SIGBUS, BUS_ADRERR, &mapping[FILESIZE+10]),
T(4, SIGFPE, DIVISION_BY_ZERO_SI_CODE, 0),
#undef T
};
for(i = 0; i < sizeof(tests)/sizeof(*tests); i++) {
cur_test = &tests[i];
if (sigsetjmp(escape, 1) == 0) {
fprintf(stderr, "Test %d: ", i+1);
tests[i].test();
fprintf(stderr, " FAIL: no fault, or handler returned\n");
}
}
}
return 0;
}
static int zero()
{
return 0;
}
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