/*++
Function:
GetThreadContext
See MSDN doc.
--*/
BOOL
CONTEXT_GetThreadContext(
DWORD dwProcessId,
pthread_t self,
LPCONTEXT lpContext)
{
BOOL ret = FALSE;
if (lpContext == NULL)
{
ERROR("Invalid lpContext parameter value\n");
SetLastError(ERROR_NOACCESS);
goto EXIT;
}
if (GetCurrentProcessId() == dwProcessId)
{
if (self != pthread_self())
{
// the target thread is in the current process, but isn't
// the current one: extract the CONTEXT from the Mach thread.
mach_port_t mptPort;
mptPort = pthread_mach_thread_np(self);
ret = (CONTEXT_GetThreadContextFromPort(mptPort, lpContext) == KERN_SUCCESS);
}
else
{
CONTEXT_CaptureContext(lpContext);
ret = TRUE;
}
}
else
{
ASSERT("Cross-process GetThreadContext() is not supported on this platform\n");
SetLastError(ERROR_NOACCESS);
}
EXIT:
return ret;
}
kern_return_t
catch_exception_raise(
mach_port_t exception_port, // [in] Mach Port that is listening to the exception
mach_port_t thread, // [in] thread the exception happened on
mach_port_t task, // [in] task the exception happened on
exception_type_t exception, // [in] The type of the exception
exception_data_t code, // [in] A machine dependent array indicating a particular instance of exception
mach_msg_type_number_t code_count) // [in] The size of the buffer (in natural-sized units).
{
kern_return_t MachRet;
ppc_thread_state_t ThreadState;
unsigned int count = sizeof(ThreadState)/sizeof(unsigned);
CONTEXT ThreadContext;
EXCEPTION_RECORD ExceptionRecord;
void *FramePointer;
ThreadContext.ContextFlags = CONTEXT_FULL;
CONTEXT_GetThreadContextFromPort(thread, &ThreadContext);
// We need to hijack the thread to point to PAL_DispatchException
MachRet = thread_get_state(thread,
MACHINE_THREAD_STATE,
(thread_state_t)&ThreadState,
&count);
if (MachRet != KERN_SUCCESS)
{
UTIL_SetLastErrorFromMach(MachRet);
ExitProcess(GetLastError());
}
ExceptionRecord.ExceptionCode = exception_from_trap_code(exception, code, code_count);
// If we're in single step mode, disable it since we're going to call PAL_DispatchException
if (ExceptionRecord.ExceptionCode == EXCEPTION_SINGLE_STEP)
{
ThreadState.srr1 &= ~0x400UL;
}
ExceptionRecord.ExceptionFlags = EXCEPTION_IS_SIGNAL;
ExceptionRecord.ExceptionRecord = NULL;
ExceptionRecord.ExceptionAddress = (void *)ThreadContext.Iar;
ExceptionRecord.NumberParameters = 0;
FramePointer =(void *) ThreadState.r1;
// Make sure it's naturally aligned
FramePointer = FramePointer - ((unsigned)FramePointer % 8);
// Move it pass the red zone
FramePointer -= C_RED_ZONE;
// Put the Context on the stack
FramePointer -= sizeof(CONTEXT);
*(CONTEXT *)FramePointer = ThreadContext;
ThreadState.r3 = (unsigned)FramePointer;
// Put the exception record on the stack
FramePointer -= sizeof(EXCEPTION_RECORD);
*(EXCEPTION_RECORD *)FramePointer = ExceptionRecord;
ThreadState.r4 = (unsigned)FramePointer;
// Add room for the args to spill
FramePointer -= 2*sizeof(void *);
// Add room for the linking area (24 bytes)
FramePointer -= 24;
*(unsigned *)FramePointer = ThreadState.r1;
// Make the instruction register point to DispatchException
ThreadState.srr0 =(unsigned) &PAL_DispatchException;
ThreadState.r1 = (unsigned)FramePointer;
// Now set the thread state for the faulting thread so that PAL_DispatchException executes next
MachRet = thread_set_state(thread,
MACHINE_THREAD_STATE,
(thread_state_t)&ThreadState,
count);
if (MachRet != KERN_SUCCESS)
{
UTIL_SetLastErrorFromMach(MachRet);
ExitProcess(GetLastError());
}
// We're done!
return KERN_SUCCESS ;
}
