/* x86 variant of the amd64-solaris/context_gpr.c test. */
#include <assert.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <sys/ucontext.h>
static siginfo_t si;
static ucontext_t uc;
/* x0 is always zero, but is visible to Valgrind as uninitialised. */
static int x0;
static void sighandler(int sig, siginfo_t *sip, ucontext_t *ucp)
{
si = *sip;
uc = *ucp;
ucp->uc_mcontext.gregs[ECX] = x0;
}
int main(void)
{
struct sigaction sa;
pid_t pid;
int eax, ebx, ecx, edx, esi, edi;
int y0;
/* Uninitialised, but we know px[0] is 0x0. */
int *px = malloc(sizeof(*px));
x0 = px[0];
/* Uninitialised, but we know py[0] is 0x0. */
int *py = malloc(sizeof(*py));
y0 = py[0];
sa.sa_handler = sighandler;
sa.sa_flags = SA_SIGINFO;
if (sigfillset(&sa.sa_mask)) {
perror("sigfillset");
return 1;
}
if (sigaction(SIGUSR1, &sa, NULL)) {
perror("sigaction");
return 1;
}
pid = getpid();
__asm__ __volatile__(
/* Set values in general purpose registers. */
"movl %[y0], %%ebx\n"
"movl $0xf1, %%ecx\n"
"movl $0xf2, %%edx\n"
"movl $0xf3, %%esi\n"
"movl $0xf4, %%edi\n"
/* Prepare syscall parameters. */
"pushl %[sig]\n"
"pushl %[pid]\n"
"pushl $0xdeadbeef\n"
"movl %[scall], %%eax\n"
/* Trigger the signal handler. */
"int $0x91\n"
"addl $12, %%esp\n"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx), "=S" (esi),
"=D" (edi)
: [scall] "i" (SYS_kill), [pid] "a" (pid), [sig] "i" (SIGUSR1),
[y0] "m" (y0)
: "cc", "memory");
printf("Values in the signal handler:\n");
printf(" eax=%#x, edx=%#x, esi=%#x, edi=%#x\n",
uc.uc_mcontext.gregs[EAX], uc.uc_mcontext.gregs[EDX],
uc.uc_mcontext.gregs[ESI], uc.uc_mcontext.gregs[EDI]);
/* Check that ebx contains an uninitialised value (origin is py[0]). */
if (uc.uc_mcontext.gregs[EBX])
assert(0);
printf("Values after the return from the signal handler:\n");
printf(" eax=%#x, edx=%#x, esi=%#x, edi=%#x\n", eax, edx, esi, edi);
/* Check that ebx and ecx contain uninitialised values (origin is py[0]
and px[0], respectively). */
if (ebx || ecx)
assert(0);
return 0;
}