void
mono_arch_handle_altstack_exception (void *sigctx, MONO_SIG_HANDLER_INFO_TYPE *siginfo, gpointer fault_addr, gboolean stack_ovf)
{
#ifdef MONO_ARCH_USE_SIGACTION
MonoException *exc = NULL;
ucontext_t *ctx = (ucontext_t*)sigctx;
MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), (gpointer)UCONTEXT_REG_EIP (ctx), NULL);
gpointer *sp;
int frame_size;
/* if we didn't find a managed method for the ip address and it matches the fault
* address, we assume we followed a broken pointer during an indirect call, so
* we try the lookup again with the return address pushed on the stack
*/
if (!ji && fault_addr == (gpointer)UCONTEXT_REG_EIP (ctx)) {
glong *sp = (gpointer)UCONTEXT_REG_ESP (ctx);
ji = mini_jit_info_table_find (mono_domain_get (), (gpointer)sp [0], NULL);
if (ji)
UCONTEXT_REG_EIP (ctx) = sp [0];
}
if (stack_ovf)
exc = mono_domain_get ()->stack_overflow_ex;
if (!ji)
mono_handle_native_sigsegv (SIGSEGV, sigctx, siginfo);
/* setup a call frame on the real stack so that control is returned there
* and exception handling can continue.
* If this was a stack overflow the caller already ensured the stack pages
* needed have been unprotected.
* The frame looks like:
* ucontext struct
* test_only arg
* exception arg
* ctx arg
* return ip
*/
// FIXME: test_only is no more.
frame_size = sizeof (MonoContext) + sizeof (gpointer) * 4;
frame_size += 15;
frame_size &= ~15;
sp = (gpointer)(UCONTEXT_REG_ESP (ctx) & ~15);
sp = (gpointer)((char*)sp - frame_size);
/* the incoming arguments are aligned to 16 bytes boundaries, so the return address IP
* goes at sp [-1]
*/
sp [-1] = (gpointer)UCONTEXT_REG_EIP (ctx);
sp [0] = sp + 4;
sp [1] = exc;
sp [2] = (gpointer)stack_ovf;
mono_sigctx_to_monoctx (sigctx, (MonoContext*)(sp + 4));
/* at the return form the signal handler execution starts in altstack_handle_and_restore() */
UCONTEXT_REG_EIP (ctx) = (unsigned long)altstack_handle_and_restore;
UCONTEXT_REG_ESP (ctx) = (unsigned long)(sp - 1);
#endif
}
LONG CALLBACK seh_unhandled_exception_filter(EXCEPTION_POINTERS* ep)
{
#ifndef MONO_CROSS_COMPILE
if (mono_old_win_toplevel_exception_filter) {
return (*mono_old_win_toplevel_exception_filter)(ep);
}
#endif
mono_handle_native_sigsegv (SIGSEGV, NULL, NULL);
return EXCEPTION_CONTINUE_SEARCH;
}
SIG_HANDLER_FUNC (static, sigabrt_signal_handler)
{
MonoJitInfo *ji = NULL;
GET_CONTEXT;
if (mono_thread_internal_current ())
ji = mono_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context(ctx));
if (!ji) {
if (mono_chain_signal (SIG_HANDLER_PARAMS))
return;
mono_handle_native_sigsegv (SIGABRT, ctx);
}
}
static void
altstack_handle_and_restore (MonoContext *ctx, MonoObject *obj, gboolean stack_ovf)
{
MonoContext mctx;
MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), MONO_CONTEXT_GET_IP (ctx), NULL);
if (!ji)
mono_handle_native_sigsegv (SIGSEGV, NULL, NULL);
mctx = *ctx;
mono_handle_exception (&mctx, obj);
if (stack_ovf)
prepare_for_guard_pages (&mctx);
mono_restore_context (&mctx);
}
void
mono_arch_handle_altstack_exception (void *sigctx, MONO_SIG_HANDLER_INFO_TYPE *siginfo, gpointer fault_addr, gboolean stack_ovf)
{
#if defined(MONO_ARCH_USE_SIGACTION)
MonoException *exc = NULL;
MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), (char *)UCONTEXT_REG_RIP (sigctx), NULL);
gpointer *sp;
int frame_size;
MonoContext *copied_ctx;
if (stack_ovf)
exc = mono_domain_get ()->stack_overflow_ex;
if (!ji)
mono_handle_native_sigsegv (SIGSEGV, sigctx, siginfo);
/* setup a call frame on the real stack so that control is returned there
* and exception handling can continue.
* The frame looks like:
* ucontext struct
* ...
* return ip
* 128 is the size of the red zone
*/
frame_size = sizeof (MonoContext) + sizeof (gpointer) * 4 + 128;
frame_size += 15;
frame_size &= ~15;
sp = (gpointer *)(UCONTEXT_REG_RSP (sigctx) & ~15);
sp = (gpointer *)((char*)sp - frame_size);
copied_ctx = (MonoContext*)(sp + 4);
/* the arguments must be aligned */
sp [-1] = (gpointer)UCONTEXT_REG_RIP (sigctx);
mono_sigctx_to_monoctx (sigctx, copied_ctx);
/* at the return form the signal handler execution starts in altstack_handle_and_restore() */
UCONTEXT_REG_RIP (sigctx) = (unsigned long)altstack_handle_and_restore;
UCONTEXT_REG_RSP (sigctx) = (unsigned long)(sp - 1);
UCONTEXT_REG_RDI (sigctx) = (unsigned long)(copied_ctx);
UCONTEXT_REG_RSI (sigctx) = (guint64)exc;
UCONTEXT_REG_RDX (sigctx) = stack_ovf;
#endif
}
void
mono_arch_handle_altstack_exception (void *sigctx, gpointer fault_addr, gboolean stack_ovf)
{
#ifdef MONO_CROSS_COMPILE
g_assert_not_reached ();
#else
#ifdef MONO_ARCH_USE_SIGACTION
os_ucontext *uc = (ucontext_t*)sigctx;
os_ucontext *uc_copy;
MonoJitInfo *ji = mini_jit_info_table_find (mono_domain_get (), mono_arch_ip_from_context (sigctx), NULL);
gpointer *sp;
int frame_size;
if (stack_ovf) {
const char *method;
/* we don't do much now, but we can warn the user with a useful message */
fprintf (stderr, "Stack overflow: IP: %p, SP: %p\n", mono_arch_ip_from_context (sigctx), (gpointer)UCONTEXT_REG_Rn(uc, 1));
if (ji && jinfo_get_method (ji))
method = mono_method_full_name (jinfo_get_method (ji), TRUE);
else
method = "Unmanaged";
fprintf (stderr, "At %s\n", method);
abort ();
}
if (!ji)
mono_handle_native_sigsegv (SIGSEGV, sigctx);
/* setup a call frame on the real stack so that control is returned there
* and exception handling can continue.
* The frame looks like:
* ucontext struct
* ...
* 224 is the size of the red zone
*/
frame_size = sizeof (ucontext_t) + sizeof (gpointer) * 16 + 224;
frame_size += 15;
frame_size &= ~15;
sp = (gpointer)(UCONTEXT_REG_Rn(uc, 1) & ~15);
sp = (gpointer)((char*)sp - frame_size);
/* may need to adjust pointers in the new struct copy, depending on the OS */
uc_copy = (ucontext_t*)(sp + 16);
memcpy (uc_copy, uc, sizeof (os_ucontext));
#if defined(__linux__) && !defined(__mono_ppc64__)
uc_copy->uc_mcontext.uc_regs = (gpointer)((char*)uc_copy + ((char*)uc->uc_mcontext.uc_regs - (char*)uc));
#endif
g_assert (mono_arch_ip_from_context (uc) == mono_arch_ip_from_context (uc_copy));
/* at the return form the signal handler execution starts in altstack_handle_and_restore() */
UCONTEXT_REG_LNK(uc) = UCONTEXT_REG_NIP(uc);
#ifdef PPC_USES_FUNCTION_DESCRIPTOR
{
MonoPPCFunctionDescriptor *handler_ftnptr = (MonoPPCFunctionDescriptor*)altstack_handle_and_restore;
UCONTEXT_REG_NIP(uc) = (gulong)handler_ftnptr->code;
UCONTEXT_REG_Rn(uc, 2) = (gulong)handler_ftnptr->toc;
}
#else
UCONTEXT_REG_NIP(uc) = (unsigned long)altstack_handle_and_restore;
#endif
UCONTEXT_REG_Rn(uc, 1) = (unsigned long)sp;
UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG) = (unsigned long)(sp + 16);
UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 1) = 0;
UCONTEXT_REG_Rn(uc, PPC_FIRST_ARG_REG + 2) = 0;
#endif
#endif /* !MONO_CROSS_COMPILE */
}