ducky.errors module

exception ducky.errors.AccessViolationError(message=None)

Bases: ducky.errors.Error

Raised when an operation was requested without having adequate permission to do so. message attribute will provide better idea about the fault.

exception ducky.errors.AssemblerError(location=None, message=None, line=None, info=None)

Bases: ducky.errors.Error

Base class for all assembler-related exceptions. Provides common properties, helping to locate related input in the source file.

Parameters:

• location (ducky.cpu.assembly.SourceLocation) – if set, points to the location in the source file that was processed when the exception occured.
• message (str) – more detailed description.
• line (str) – input source line.
• info – additional details of the exception. This value is usually part of the message, but is stored as well.

create_text()

log(logger)

exception ducky.errors.AssemblyIllegalCharError(c=None, **kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.AssemblyParseError(token=None, **kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.BadLinkerScriptError(script, exc, *args, **kwargs)

Bases: ducky.errors.LinkerError

exception ducky.errors.ConflictingNamesError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.CoprocessorError(msg, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Base class for coprocessor errors. Raised when coprocessors needs to signal its own exception, when none of alread yavailable exceptions would do.

EXCEPTION_INDEX = 25

exception ducky.errors.DisassembleMismatchError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.DivideByZeroError(*args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when divisor in a mathematical operation was equal to zero.

EXCEPTION_INDEX = 18

exception ducky.errors.EncodingLargeValueError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.Error(message=None)

Bases: exceptions.Exception

Base class for all Ducky exceptions.

Parameters:message (str) – optional description.

log(logger)

class ducky.errors.ExceptionList

Bases: enum.IntEnum

List of exception IDs (EVT indices).

COUNT = 32

CoprocessorError = 25

DivideByZero = 18

DoubleFault = 21

FIRST_HW = 0

FIRST_SW = 16

InvalidException = 24

InvalidInstSet = 17

InvalidOpcode = 16

LAST_HW = 15

LAST_SW = 31

MemoryAccess = 22

PrivilegedInstr = 20

RegisterAccess = 23

UnalignedAccess = 19

_member_map_ = OrderedDict([('FIRST_HW', <ExceptionList.FIRST_HW: 0>), ('LAST_HW', <ExceptionList.LAST_HW: 15>), ('InvalidOpcode', <ExceptionList.InvalidOpcode: 16>), ('FIRST_SW', <ExceptionList.InvalidOpcode: 16>), ('InvalidInstSet', <ExceptionList.InvalidInstSet: 17>), ('DivideByZero', <ExceptionList.DivideByZero: 18>), ('UnalignedAccess', <ExceptionList.UnalignedAccess: 19>), ('PrivilegedInstr', <ExceptionList.PrivilegedInstr: 20>), ('DoubleFault', <ExceptionList.DoubleFault: 21>), ('MemoryAccess', <ExceptionList.MemoryAccess: 22>), ('RegisterAccess', <ExceptionList.RegisterAccess: 23>), ('InvalidException', <ExceptionList.InvalidException: 24>), ('CoprocessorError', <ExceptionList.CoprocessorError: 25>), ('LAST_SW', <ExceptionList.LAST_SW: 31>), ('COUNT', <ExceptionList.COUNT: 32>)])

_member_names_ = ['FIRST_HW', 'LAST_HW', 'InvalidOpcode', 'InvalidInstSet', 'DivideByZero', 'UnalignedAccess', 'PrivilegedInstr', 'DoubleFault', 'MemoryAccess', 'RegisterAccess', 'InvalidException', 'CoprocessorError', 'LAST_SW', 'COUNT']

_member_type_

alias of int

_value2member_map_ = {0: <ExceptionList.FIRST_HW: 0>, 32: <ExceptionList.COUNT: 32>, 15: <ExceptionList.LAST_HW: 15>, 16: <ExceptionList.InvalidOpcode: 16>, 17: <ExceptionList.InvalidInstSet: 17>, 18: <ExceptionList.DivideByZero: 18>, 19: <ExceptionList.UnalignedAccess: 19>, 20: <ExceptionList.PrivilegedInstr: 20>, 21: <ExceptionList.DoubleFault: 21>, 22: <ExceptionList.MemoryAccess: 22>, 23: <ExceptionList.RegisterAccess: 23>, 24: <ExceptionList.InvalidException: 24>, 25: <ExceptionList.CoprocessorError: 25>, 31: <ExceptionList.LAST_SW: 31>}

exception ducky.errors.ExecutionException(msg, core=None, ip=None)

Bases: exceptions.Exception

Base class for all execution-related exceptions, i.e. exceptions raised as a direct result of requests made by running code. Runnign code can then take care of handling these exceptions, usually by preparing service routines and setting up the EVT.

Unless said otherwise, the exception is always raised before making any changes in the VM state.

Parameters:

• msg (string) – message describing exceptional state.
• core (ducky.cpu.CPUCore) – CPU core that raised exception, if any.
• ip (u32_t) – address of an instruction that caused exception, if any.

runtime_handle()

This method is called by CPU code, to find out if it is possible for runtime to handle the exception, and possibly recover from it. If it is possible, this method should make necessary arrangements, and then return True. Many exceptions, e.g. when division by zero was requested, will tell CPU to run exception service routine, and by returning True signal that it’s not necessary to take care of such exception anymore.

Return type:bool Returns:True when it’s no longer necessary for VM code to take care of this exception.

class ducky.errors.ExecutionException__SimpleESR

Bases: object

Helper mixin class - as one of parents, it brings to its children very simle - and most of the time sufficient - implementation of runtime_handle method. Such exceptions will tell CPU to run exception service routine with a secific index, specified by class variable EXCEPTION_INDEX.

The address of the offensive instruction - or the value of IP when exception was raised, since there may be exceptions not raised in response to the executed instruction - is passed to CPU as the first argument of ESR.

runtime_handle()

exception ducky.errors.IncompatibleSectionFlagsError(dst_section, src_section, *args, **kwargs)

Bases: ducky.errors.LinkerError

exception ducky.errors.IncompleteDirectiveError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.InvalidExceptionError(exc_index, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when requested exception index is invalid (out of bounds).

EXCEPTION_INDEX = 24

exception ducky.errors.InvalidFrameError(saved_sp, current_sp, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when VM checks each call stack frame to be cleaned before it’s left, and there are some values on stack when ret or retint are executed. In such case, the actual SP values does not equal to a saved one, and exception is raised.

Parameters:

• saved_sp (u32_t) – SP as saved at the moment the frame was created.
• current_sp (u32_t) – current SP

runtime_handle()

exception ducky.errors.InvalidInstructionSetError(inst_set, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when switch to unknown or invalid instruction set was requested.

Parameters:inst_set (int) – instruction set id.

EXCEPTION_INDEX = 17

exception ducky.errors.InvalidOpcodeError(opcode, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when unknown or invalid opcode is found in instruction.

Parameters:opcode (int) – wrong opcode.

EXCEPTION_INDEX = 16

exception ducky.errors.InvalidResourceError(message=None)

Bases: ducky.errors.Error

Raised when an operation was requested on somehow invalid resource. message attribute will provide better idea about the fault.

exception ducky.errors.LinkerError(message=None)

Bases: ducky.errors.Error

exception ducky.errors.MemoryAccessError(access, address, pte, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when MMU decides the requested memory operation is now allowed, e.g. when page tables are enabled, and corresponding PTE denies write access.

Parameters:

• access (str) – read, write or execute.
• address (u32_t) – address where memory access shuld have happen.
• pte (ducky.mm.PageTableEntry) – PTE guarding this particular memory location.

EXCEPTION_INDEX = 22

exception ducky.errors.OperandMismatchError(instr, expected, actual)

Bases: ducky.errors.Error

exception ducky.errors.PatchTooLargeError(message=None)

Bases: ducky.errors.LinkerError

exception ducky.errors.PrivilegedInstructionError(*args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when privileged instruction was about to be executed in non-privileged mode.

EXCEPTION_INDEX = 20

exception ducky.errors.RegisterAccessError(access, reg, *args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when instruction tries to access a registerall which is not available for requested operation, e.g. writing into read-only control register will raise this exception.

Parameters:

• access (str) – read or write.
• reg (str) – register name.

EXCEPTION_INDEX = 23

exception ducky.errors.TooManyLabelsError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.UnalignedAccessError(*args, **kwargs)

Bases: ducky.errors.ExecutionException__SimpleESR, ducky.errors.ExecutionException

Raised when only properly aligned memory access is allowed, and running code attempts to access memory without honoring this restriction (e.g. LW reading from byte-aligned address).

EXCEPTION_INDEX = 19

exception ducky.errors.UnalignedJumpTargetError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.UnknownDestinationSectionError(src_section, *args, **kwargs)

Bases: ducky.errors.LinkerError

exception ducky.errors.UnknownFileError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.UnknownInstructionError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.UnknownPatternError(**kwargs)

Bases: ducky.errors.AssemblerError

exception ducky.errors.UnknownSymbolError(message=None)

Bases: ducky.errors.LinkerError