static bool advanceCursor(KSStackCursor *cursor)
{
MachineContextCursor* context = (MachineContextCursor*)cursor->context;
uintptr_t nextAddress = 0;
if(cursor->state.currentDepth >= context->maxStackDepth)
{
cursor->state.hasGivenUp = true;
return false;
}
if(context->instructionAddress == 0)
{
context->instructionAddress = kscpu_instructionAddress(context->machineContext);
if(context->instructionAddress == 0)
{
return false;
}
nextAddress = context->instructionAddress;
goto successfulExit;
}
if(context->linkRegister == 0 && !context->isPastFramePointer)
{
// Link register, if available, is the second address in the trace.
context->linkRegister = kscpu_linkRegister(context->machineContext);
if(context->linkRegister != 0)
{
nextAddress = context->linkRegister;
goto successfulExit;
}
}
if(context->currentFrame.previous == NULL)
{
if(context->isPastFramePointer)
{
return false;
}
context->currentFrame.previous = (struct FrameEntry*)kscpu_framePointer(context->machineContext);
context->isPastFramePointer = true;
}
if(!ksmem_copySafely(context->currentFrame.previous, &context->currentFrame, sizeof(context->currentFrame)))
{
return false;
}
if(context->currentFrame.previous == 0 || context->currentFrame.return_address == 0)
{
return false;
}
nextAddress = context->currentFrame.return_address;
successfulExit:
cursor->stackEntry.address = kscpu_normaliseInstructionPointer(nextAddress);
cursor->state.currentDepth++;
return true;
}
void kssc_initWithMachineContext(KSStackCursor *cursor, int maxStackDepth, const struct KSMachineContext* machineContext)
{
kssc_initCursor(cursor, maxStackDepth, kscpu_instructionAddress(machineContext));
cursor->advanceCursor = advanceCursor;
MachineContextCursor* cursorContext = (MachineContextCursor*)cursor->context;
cursorContext->machineContext = machineContext;
cursorContext->instructionAddress = cursor->stackEntry.address;
}
