1bff4673bSJim Ingham #include <signal.h>
2bff4673bSJim Ingham #include <unistd.h>
3bff4673bSJim Ingham #include <stdlib.h>
4bff4673bSJim Ingham #include <sys/mman.h>
5bff4673bSJim Ingham #include <stdio.h>
6b369762bSJim Ingham #include <mach/mach.h>
7b369762bSJim Ingham #include <mach/mach_vm.h>
8bff4673bSJim Ingham
9b369762bSJim Ingham int *g_int_ptr = NULL;
10b369762bSJim Ingham size_t g_size = 10*sizeof(int);
11bff4673bSJim Ingham
12bff4673bSJim Ingham void
saction_handler(int signo,siginfo_t info,void * baton)13bff4673bSJim Ingham saction_handler(int signo, siginfo_t info, void *baton) {
14b369762bSJim Ingham printf("Got into handler.\n"); // stop here in the signal handler
15b369762bSJim Ingham kern_return_t success
16*2622c5e2SAugusto Noronha = mach_vm_protect(mach_task_self(), (mach_vm_address_t) g_int_ptr,
17b369762bSJim Ingham g_size, 0, VM_PROT_READ|VM_PROT_WRITE);
18b369762bSJim Ingham g_int_ptr[1] = 20;
19bff4673bSJim Ingham }
20bff4673bSJim Ingham int
main()21bff4673bSJim Ingham main()
22bff4673bSJim Ingham {
23b369762bSJim Ingham kern_return_t vm_result = vm_allocate(mach_task_self(), &g_int_ptr, g_size, VM_FLAGS_ANYWHERE);
24b369762bSJim Ingham for (int i = 0; i < 10; i++)
25b369762bSJim Ingham g_int_ptr[i] = i * 10;
26b369762bSJim Ingham
27*2622c5e2SAugusto Noronha vm_result = mach_vm_protect(mach_task_self(), (mach_vm_address_t) g_int_ptr, g_size, 0, VM_PROT_NONE);
28bff4673bSJim Ingham struct sigaction my_action;
29bff4673bSJim Ingham sigemptyset(&my_action.sa_mask);
30bff4673bSJim Ingham my_action.sa_handler = (void (*)(int)) saction_handler;
31bff4673bSJim Ingham my_action.sa_flags = SA_SIGINFO;
32bff4673bSJim Ingham
33bff4673bSJim Ingham sigaction(SIGBUS, &my_action, NULL); // Stop here to get things going.
34b369762bSJim Ingham int local_value = g_int_ptr[1];
35bff4673bSJim Ingham return local_value; // Break here to make sure we got past the signal handler
36bff4673bSJim Ingham }
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