none/tests/x86-linux/sigcontext.c

   1 #define _GNU_SOURCE
   2
   3 #include <stdio.h>
   4 #include <signal.h>
   5 #include <unistd.h>
   6 #include <sys/ucontext.h>
   7 #include <asm/unistd.h>
   8
   9 #define VAL1 0x11223344
  10 #define VAL2 0x44332211
  11
  12 static void handler1(int sig, siginfo_t *si, ucontext_t *uc)
  13 {
  14         /* Since the handler will be called as kill leaves the kernel,
  15            this is replacing the kill syscall's return value. */
  16         if (uc->uc_mcontext.gregs[REG_EAX] != 0)
  17                 printf("FAILED: handler2 expected eax == 0, not %d\n", uc->uc_mcontext.gregs[REG_EAX]);
  18         uc->uc_mcontext.gregs[REG_EAX] = VAL1;
  19
  20         asm volatile (
  21                 "movl   $0, %%edx\n"
  22                 "movl   $0, %%esi\n"
  23                 "movl   $0, %%edi\n"
  24                 : : : "edx", "esi", "edi");
  25 }
  26
  27 static void handler2(int sig, struct sigcontext sc)
  28 {
  29         /* Since the handler will be called as kill leaves the kernel,
  30            this is replacing the kill syscall's return value. */
  31         if (sc.eax != 0)
  32                 printf("FAILED: handler2 expected eax == 0, not %p\n", (void*)sc.eax);
  33
  34         sc.eax = VAL2;
  35
  36         asm volatile (
  37                 "movl   $0, %%edx\n"
  38                 "movl   $0, %%esi\n"
  39                 "movl   $0, %%edi\n"
  40                 : : : "edx", "esi", "edi");
  41 }
  42
  43 int main()
  44 {
  45         struct sigaction sa;
  46         int ret;
  47         int v2, v3, v4;
  48
  49         sa.sa_handler = (void*)handler1;
  50         sa.sa_flags = SA_SIGINFO;
  51         sigfillset(&sa.sa_mask);
  52
  53         sigaction(SIGUSR1, &sa, NULL);
  54
  55         sa.sa_handler = (void*)handler2;
  56         sa.sa_flags = 0;
  57         sigfillset(&sa.sa_mask);
  58
  59         sigaction(SIGUSR2, &sa, NULL);
  60
  61         asm volatile (
  62                 //"movl $0x11111111, %%ebp\n"
  63                 "movl   $0x22222222, %%edx\n"
  64                 "movl   $0x33333333, %%esi\n"
  65                 "movl   $0x44444444, %%edi\n"
  66                 "int $0x80"
  67                 : "=a" (ret),  "=d" (v2), "=S" (v3), "=D" (v4)
  68                 : "0" (__NR_kill), "b" (getpid()), "c" (SIGUSR1));
  69         printf("v2=%x v3=%x v4=%x\n", v2, v3, v4);
  70
  71         if (ret == VAL1)
  72                 printf("PASS %x\n", ret);
  73         else
  74                 printf("FAIL ret=%x not %x\n", ret, VAL1);
  75
  76         asm volatile (
  77                 //"movl $0x11111111, %%ebp\n"
  78                 "movl   $0x22222222, %%edx\n"
  79                 "movl   $0x33333333, %%esi\n"
  80                 "movl   $0x44444444, %%edi\n"
  81                 "int $0x80"
  82                 : "=a" (ret),  "=d" (v2), "=S" (v3), "=D" (v4)
  83                 : "0" (__NR_kill), "b" (getpid()), "c" (SIGUSR2));
  84         printf("v2=%x v3=%x v4=%x\n", v2, v3, v4);
  85
  86         if (ret == VAL2)
  87                 printf("PASS %x\n", ret);
  88         else
  89                 printf("FAIL ret=%x not %x\n", ret, VAL2);
  90
  91         return 0;
  92 }