/*++
Function:
RtlpRaiseException
Parameters:
ExceptionRecord - the Windows exception record to throw
Note:
The name of this function and the name of the ExceptionRecord
parameter is used in the sos lldb plugin code to read the exception
record. See coreclr\src\ToolBox\SOS\lldbplugin\debugclient.cpp.
--*/
PAL_NORETURN
static void RtlpRaiseException(EXCEPTION_RECORD *ExceptionRecord)
{
// Capture the context of RtlpRaiseException.
CONTEXT ContextRecord;
ZeroMemory(&ContextRecord, sizeof(CONTEXT));
ContextRecord.ContextFlags = CONTEXT_FULL;
CONTEXT_CaptureContext(&ContextRecord);
// Find the caller of RtlpRaiseException.
PAL_VirtualUnwind(&ContextRecord, NULL);
// The frame we're looking at now is RaiseException. We have to unwind one
// level further to get the actual context user code could be resumed at.
PAL_VirtualUnwind(&ContextRecord, NULL);
#if defined(_X86_)
ExceptionRecord->ExceptionAddress = (void *) ContextRecord.Eip;
#elif defined(_AMD64_)
ExceptionRecord->ExceptionAddress = (void *) ContextRecord.Rip;
#elif defined(_ARM_) || defined(_ARM64_)
ExceptionRecord->ExceptionAddress = (void *) ContextRecord.Pc;
#else
#error unsupported architecture
#endif
EXCEPTION_POINTERS pointers;
pointers.ExceptionRecord = ExceptionRecord;
pointers.ContextRecord = &ContextRecord;
SEHRaiseException(InternalGetCurrentThread(), &pointers, 0);
}
void PAL_DispatchException(PCONTEXT pContext, PEXCEPTION_RECORD pExRecord)
{
MSG_SET_THREAD MsgSet;
kern_return_t MachRet;
EXCEPTION_POINTERS pointers;
pointers.ExceptionRecord = pExRecord;
pointers.ContextRecord = pContext;
// Raise the exception
SEHRaiseException(&pointers, 0);
// We need to send a message to the worker thread so that it can set our thread context
// Setup the heaer
MsgSet.m_MsgHdr.msgh_size = sizeof(MsgSet);
MsgSet.m_MsgHdr.msgh_bits = MACH_MSGH_BITS_REMOTE(MACH_MSG_TYPE_MAKE_SEND|MACH_MSG_TYPE_MOVE_RECEIVE); // Simple Message
MsgSet.m_MsgHdr.msgh_remote_port = s_ExceptionPort; // Send, dest port
MsgSet.m_MsgHdr.msgh_local_port = MACH_PORT_NULL; // We're not expecting a msg back
MsgSet.m_MsgHdr.msgh_id = SET_THREAD_MESSAGE_ID; // Message ID
MsgSet.m_MsgHdr.msgh_reserved = 0; // Not used
// Setup the thread and thread context
MsgSet.m_ThreadPort = mach_thread_self();
MsgSet.m_ThreadContext = *pContext;
// Send the message to the exception port
MachRet = mach_msg(&MsgSet.m_MsgHdr,
MACH_SEND_MSG,
MsgSet.m_MsgHdr.msgh_size,
0,
MACH_PORT_NULL,
MACH_MSG_TIMEOUT_NONE,
MACH_PORT_NULL);
if (MachRet != KERN_SUCCESS)
{
UTIL_SetLastErrorFromMach(MachRet);
ExitProcess(GetLastError());
}
// Make sure we don't do anything
while(1)
{
sched_yield();
}
}
/*++
Function:
RaiseException
See MSDN doc.
--*/
VOID
PALAPI
RaiseException(
IN DWORD dwExceptionCode,
IN DWORD dwExceptionFlags,
IN DWORD nNumberOfArguments,
IN CONST ULONG_PTR *lpArguments)
{
EXCEPTION_RECORD record;
EXCEPTION_POINTERS exceptionPointers;
CONTEXT context;
ENTRY("RaiseException (dwCode=%#x, dwFlags=%#x, nArgs=%u, lpArgs=%p)\n",
dwExceptionCode, dwExceptionFlags, nNumberOfArguments, lpArguments);
/* Validate parameters */
if( dwExceptionCode & RESERVED_SEH_BIT)
{
WARN("Exception code %08x has bit 28 set : clearing it.\n",
dwExceptionCode);
dwExceptionCode ^= RESERVED_SEH_BIT;
}
if( dwExceptionFlags && ( dwExceptionFlags != EXCEPTION_NONCONTINUABLE ) )
{
ERROR("Unkown exception flag %08x (ignoring)\n", dwExceptionFlags);
}
/* Build exception record */
TRACE("Building exception record %p\n", &record);
record.ExceptionCode = dwExceptionCode;
record.ExceptionAddress = RaiseException;
record.ExceptionRecord = NULL;
if( lpArguments != NULL )
{
if(nNumberOfArguments>EXCEPTION_MAXIMUM_PARAMETERS)
{
WARN("Number of arguments (%d) exceeds the limit "
"EXCEPTION_MAXIMUM_PARAMETERS (%d); truncing the extra"
"parameters.\n",
nNumberOfArguments, EXCEPTION_MAXIMUM_PARAMETERS);
nNumberOfArguments = EXCEPTION_MAXIMUM_PARAMETERS;
}
memcpy(record.ExceptionInformation, lpArguments,
nNumberOfArguments*sizeof(ULONG_PTR));
}
record.NumberParameters = nNumberOfArguments;
/* from rotor_pal.doc :
"all explicitly raised exceptions may be considered non-continuable". */
record.ExceptionFlags = EXCEPTION_NONCONTINUABLE;
/* from rotor_pal.h :
On non-Win32 platforms, the CONTEXT pointer in the
PEXCEPTION_POINTERS will contain at least the CONTEXT_CONTROL registers.
*/
ZeroMemory(&context, sizeof context);
context.ContextFlags = CONTEXT_CONTROL;
if(!GetThreadContext(GetCurrentThread(),&context))
{
WARN("GetThreadContext failed!! ignoring...\n");
}
exceptionPointers.ExceptionRecord = &record;
exceptionPointers.ContextRecord = &context;
/* Let SEHRaiseException do the work */
SEHRaiseException(&exceptionPointers, 0);
LOGEXIT("RaiseException returns.\n");
}