path: root/pyvisa/errors.py

# -*- coding: utf-8 -*-
"""
    pyvisa.errors
    ~~~~~~~~~~~~~

    Defines exceptions hierarchy and textual explanations of VISA completion and error codes.

    This file is part of PyVISA.

    :copyright: 2014 by PyVISA Authors, see AUTHORS for more details.
    :license: MIT, see LICENSE for more details.
"""

from __future__ import division, print_function, absolute_import

from . import util, constants
from .constants import *

completion_and_error_messages = {

    VI_SUCCESS                 : ("VI_SUCCESS",
                                  "Operation completed successfully."),
    VI_SUCCESS_EVENT_EN        : ("VI_SUCCESS_EVENT_EN",
                                  "Specified event is already enabled for at "
                                  "least one of the specified mechanisms."),
    VI_SUCCESS_EVENT_DIS       : ("VI_SUCCESS_EVENT_DIS",
                                  "Specified event is already disabled for "
                                  "at least one of the specified mechanisms."),
    VI_SUCCESS_QUEUE_EMPTY     : ("VI_SUCCESS_QUEUE_EMPTY",
                                  "Operation completed successfully, but "
                                  "queue was already empty."),
    VI_SUCCESS_TERM_CHAR       : ("VI_SUCCESS_TERM_CHAR",
                                  "The specified termination character was "
                                  "read."),
    VI_SUCCESS_MAX_CNT         : ("VI_SUCCESS_MAX_CNT",
                                  "The number of bytes transferred is equal "
                                  "to the requested input count. More data "
                                  "may be available."),
    VI_SUCCESS_DEV_NPRESENT    : ("VI_SUCCESS_DEV_NPRESENT",
                                  "Session opened successfully, but the "
                                  "device at the specified address is not "
                                  "responding."),
    VI_SUCCESS_TRIG_MAPPED     : ("VI_SUCCESS_TRIG_MAPPED",
                                  "The path from trigSrc to trigDest is "
                                  "already mapped."),
    VI_SUCCESS_QUEUE_NEMPTY    : ("VI_SUCCESS_QUEUE_NEMPTY",
                                  "Wait terminated successfully on receipt "
                                  "of an event notification. There is at "
                                  "least one more event object of the "
                                  "requested type(s) available for this "
                                  "session."),
    VI_SUCCESS_NCHAIN          : ("VI_SUCCESS_NCHAIN",
                                  "Event handled successfully. Do not invoke "
                                  "any other handlers on this session for "
                                  "this event."),
    VI_SUCCESS_NESTED_SHARED   : ("VI_SUCCESS_NESTED_SHARED",
                                  "Operation completed successfully, and "
                                  "this session has nested shared locks."),
    VI_SUCCESS_NESTED_EXCLUSIVE: ("VI_SUCCESS_NESTED_EXCLUSIVE",
                                  "Operation completed successfully, and "
                                  "this session has nested exclusive locks."),
    VI_SUCCESS_SYNC            : ("VI_SUCCESS_SYNC",
                                  "Operation completed successfully, but the "
                                  "operation was actually synchronous rather "
                                  "than asynchronous."),
    VI_WARN_QUEUE_OVERFLOW     : ("VI_WARN_QUEUE_OVERFLOW",
                                  "VISA received more event information of "
                                  "the specified type than the configured "
                                  "queue size could hold."),
    VI_WARN_CONFIG_NLOADED     : ("VI_WARN_CONFIG_NLOADED",
                                  "The specified configuration either does "
                                  "not exist or could not be loaded. "
                                  "VISA-specified defaults will be used."),
    VI_WARN_NULL_OBJECT        : ("VI_WARN_NULL_OBJECT",
                                  "The specified object reference is "
                                  "uninitialized."),
    VI_WARN_NSUP_ATTR_STATE    : ("VI_WARN_NSUP_ATTR_STATE",
                                  "Although the specified state of the "
                                  "attribute is valid, it is not supported "
                                  "by this implementation."),
    VI_WARN_UNKNOWN_STATUS     : ("VI_WARN_UNKNOWN_STATUS",
                                  "The status code passed to the operation "
                                  "could not be interpreted."),
    VI_WARN_NSUP_BUF           : ("VI_WARN_NSUP_BUF",
                                  "The specified I/O buffer type is not "
                                  "supported."),
    VI_WARN_EXT_FUNC_NIMPL     : ("VI_WARN_EXT_FUNC_NIMPL",
                                  "The operation succeeded, but a lower "
                                  "level driver did not implement the "
                                  "extended functionality."),
    VI_ERROR_SYSTEM_ERROR      : ("VI_ERROR_SYSTEM_ERROR",
                                  "Unknown system error (miscellaneous "
                                  "error)."),
    VI_ERROR_INV_OBJECT        : ("VI_ERROR_INV_OBJECT",
                                  "The given session or object reference is "
                                  "invalid."),
    VI_ERROR_RSRC_LOCKED       : ("VI_ERROR_RSRC_LOCKED",
                                  "Specified type of lock cannot be "
                                  "obtained, or specified operation cannot "
                                  "be performed, because the resource is "
                                  "locked."),
    VI_ERROR_INV_EXPR          : ("VI_ERROR_INV_EXPR",
                                  "Invalid expression specified for search."),
    VI_ERROR_RSRC_NFOUND       : ("VI_ERROR_RSRC_NFOUND",
                                  "Insufficient location information or the "
                                  "requested device or resource is not "
                                  "present in the system."),
    VI_ERROR_INV_RSRC_NAME     : ("VI_ERROR_INV_RSRC_NAME",
                                  "Invalid resource reference specified. "
                                  "Parsing error."),
    VI_ERROR_INV_ACC_MODE      : ("VI_ERROR_INV_ACC_MODE",
                                  "Invalid access mode."),
    VI_ERROR_TMO               : ("VI_ERROR_TMO",
                                  "Timeout expired before operation "
                                  "completed."),
    VI_ERROR_CLOSING_FAILED    : ("VI_ERROR_CLOSING_FAILED",
                                  "The VISA driver failed to properly close "
                                  "the session or object reference. This "
                                  "might be due to an error freeing internal "
                                  "or OS resources, a failed network "
                                  "connection, or a lower-level driver or OS "
                                  "error."),
    VI_ERROR_INV_DEGREE        : ("VI_ERROR_INV_DEGREE",
                                  "Specified degree is invalid."),
    VI_ERROR_INV_JOB_ID        : ("VI_ERROR_INV_JOB_ID",
                                  "Specified job identifier is invalid."),
    VI_ERROR_NSUP_ATTR         : ("VI_ERROR_NSUP_ATTR",
                                  "The specified attribute is not defined or "
                                  "supported by the referenced object."),
    VI_ERROR_NSUP_ATTR_STATE   : ("VI_ERROR_NSUP_ATTR_STATE",
                                  "The specified state of the attribute is "
                                  "not valid, or is not supported as defined "
                                  "by the object."),
    VI_ERROR_ATTR_READONLY     : ("VI_ERROR_ATTR_READONLY",
                                  "The specified attribute is read-only."),
    VI_ERROR_INV_LOCK_TYPE     : ("VI_ERROR_INV_LOCK_TYPE",
                                  "The specified type of lock is not "
                                  "supported by this resource."),
    VI_ERROR_INV_ACCESS_KEY    : ("VI_ERROR_INV_ACCESS_KEY",
                                  "The access key to the resource associated "
                                  "with the specified session is invalid."),
    VI_ERROR_INV_EVENT         : ("VI_ERROR_INV_EVENT",
                                  "Specified event type is not supported by "
                                  "the resource."),
    VI_ERROR_INV_MECH          : ("VI_ERROR_INV_MECH",
                                  "Invalid mechanism specified."),
    VI_ERROR_HNDLR_NINSTALLED  : ("VI_ERROR_HNDLR_NINSTALLED",
                                  "A handler was not installed."),
    VI_ERROR_INV_HNDLR_REF     : ("VI_ERROR_INV_HNDLR_REF",
                                  "The given handler reference is either "
                                  "invalid or was not installed."),
    VI_ERROR_INV_CONTEXT       : ("VI_ERROR_INV_CONTEXT",
                                  "Specified event context is invalid."),
    VI_ERROR_QUEUE_OVERFLOW    : ("VI_ERROR_QUEUE_OVERFLOW",
                                  "The event queue for the specified type "
                                  "has overflowed (usually due to previous "
                                  "events not having been closed)."),
    VI_ERROR_NENABLED          : ("VI_ERROR_NENABLED",
                                  "You must be enabled for events of the "
                                  "specified type in order to receive them."),
    VI_ERROR_ABORT             : ("VI_ERROR_ABORT",
                                  "User abort occurred during transfer."),
    VI_ERROR_RAW_WR_PROT_VIOL  : ("VI_ERROR_RAW_WR_PROT_VIOL",
                                  "Violation of raw write protocol occurred "
                                  "during transfer."),
    VI_ERROR_RAW_RD_PROT_VIOL  : ("VI_ERROR_RAW_RD_PROT_VIOL",
                                  "Violation of raw read protocol occurred "
                                  "during transfer."),
    VI_ERROR_OUTP_PROT_VIOL    : ("VI_ERROR_OUTP_PROT_VIOL",
                                  "Device reported an output protocol error "
                                  "during transfer."),
    VI_ERROR_INP_PROT_VIOL     : ("VI_ERROR_INP_PROT_VIOL",
                                  "Device reported an input protocol error "
                                  "during transfer."),
    VI_ERROR_BERR              : ("VI_ERROR_BERR",
                                  "Bus error occurred during transfer."),
    VI_ERROR_IN_PROGRESS       : ("VI_ERROR_IN_PROGRESS",
                                  "Unable to queue the asynchronous "
                                  "operation because there is already an "
                                  "operation in progress."),
    VI_ERROR_INV_SETUP         : ("VI_ERROR_INV_SETUP",
                                  "Unable to start operation because setup "
                                  "is invalid (usually due to attributes "
                                  "being set to an inconsistent state)."),
    VI_ERROR_QUEUE_ERROR       : ("VI_ERROR_QUEUE_ERROR",
                                  "Unable to queue the asynchronous "
                                  "operation (usually due to the I/O "
                                  "completion event not being enabled or "
                                  "insufficient space in the session's "
                                  "queue)."),
    VI_ERROR_ALLOC             : ("VI_ERROR_ALLOC",
                                  "Insufficient system resources to perform "
                                  "necessary memory allocation."),
    VI_ERROR_INV_MASK          : ("VI_ERROR_INV_MASK",
                                  "Invalid buffer mask specified."),
    VI_ERROR_IO                : ("VI_ERROR_IO",
                                  "Could not perform operation because of "
                                  "I/O error."),
    VI_ERROR_INV_FMT           : ("VI_ERROR_INV_FMT",
                                  "A format specifier in the format string "
                                  "is invalid."),
    VI_ERROR_NSUP_FMT          : ("VI_ERROR_NSUP_FMT",
                                  "A format specifier in the format string "
                                  "is not supported."),
    VI_ERROR_LINE_IN_USE       : ("VI_ERROR_LINE_IN_USE",
                                  "The specified trigger line is currently "
                                  "in use."),
    VI_ERROR_NSUP_MODE         : ("VI_ERROR_NSUP_MODE",
                                  "The specified mode is not supported by "
                                  "this VISA implementation."),
    VI_ERROR_SRQ_NOCCURRED     : ("VI_ERROR_SRQ_NOCCURRED",
                                  "Service request has not been received for "
                                  "the session."),
    VI_ERROR_INV_SPACE         : ("VI_ERROR_INV_SPACE",
                                  "Invalid address space specified."),
    VI_ERROR_INV_OFFSET        : ("VI_ERROR_INV_OFFSET",
                                  "Invalid offset specified."),
    VI_ERROR_INV_WIDTH         : ("VI_ERROR_INV_WIDTH",
                                  "Invalid access width specified."),
    VI_ERROR_NSUP_OFFSET       : ("VI_ERROR_NSUP_OFFSET",
                                  "Specified offset is not accessible from "
                                  "this hardware."),
    VI_ERROR_NSUP_VAR_WIDTH    : ("VI_ERROR_NSUP_VAR_WIDTH",
                                  "Cannot support source and destination "
                                  "widths that are different."),
    VI_ERROR_WINDOW_NMAPPED    : ("VI_ERROR_WINDOW_NMAPPED",
                                  "The specified session is not currently "
                                  "mapped."),
    VI_ERROR_RESP_PENDING      : ("VI_ERROR_RESP_PENDING",
                                  "A previous response is still pending, "
                                  "causing a multiple query error."),
    VI_ERROR_NLISTENERS        : ("VI_ERROR_NLISTENERS",
                                  "No listeners condition is detected (both "
                                  "NRFD and NDAC are deasserted)."),
    VI_ERROR_NCIC              : ("VI_ERROR_NCIC",
                                  "The interface associated with this "
                                  "session is not currently the controller "
                                  "in charge."),
    VI_ERROR_NSYS_CNTLR        : ("VI_ERROR_NSYS_CNTLR",
                                  "The interface associated with this "
                                  "session is not the system controller."),
    VI_ERROR_NSUP_OPER         : ("VI_ERROR_NSUP_OPER",
                                  "The given session or object reference "
                                  "does not support this operation."),
    VI_ERROR_INTR_PENDING      : ("VI_ERROR_INTR_PENDING",
                                  "An interrupt is still pending from a "
                                  "previous call."),
    VI_ERROR_ASRL_PARITY       : ("VI_ERROR_ASRL_PARITY",
                                  "A parity error occurred during transfer."),
    VI_ERROR_ASRL_FRAMING      : ("VI_ERROR_ASRL_FRAMING",
                                  "A framing error occurred during transfer."),
    VI_ERROR_ASRL_OVERRUN      : ("VI_ERROR_ASRL_OVERRUN",
                                  "An overrun error occurred during "
                                  "transfer. A character was not read from "
                                  "the hardware before the next character "
                                  "arrived."),
    VI_ERROR_TRIG_NMAPPED      : ("VI_ERROR_TRIG_NMAPPED",
                                  "The path from trigSrc to trigDest is not "
                                  "currently mapped."),
    VI_ERROR_NSUP_ALIGN_OFFSET : ("VI_ERROR_NSUP_ALIGN_OFFSET",
                                  "The specified offset is not properly "
                                  "aligned for the access width of the "
                                  "operation."),
    VI_ERROR_USER_BUF          : ("VI_ERROR_USER_BUF",
                                  "A specified user buffer is not valid or "
                                  "cannot be accessed for the required size."),
    VI_ERROR_RSRC_BUSY         : ("VI_ERROR_RSRC_BUSY",
                                  "The resource is valid, but VISA cannot "
                                  "currently access it."),
    VI_ERROR_NSUP_WIDTH        : ("VI_ERROR_NSUP_WIDTH",
                                  "Specified width is not supported by this "
                                  "hardware."),
    VI_ERROR_INV_PARAMETER     : ("VI_ERROR_INV_PARAMETER",
                                  "The value of some parameter (which "
                                  "parameter is not known) is invalid."),
    VI_ERROR_INV_PROT          : ("VI_ERROR_INV_PROT",
                                  "The protocol specified is invalid."),
    VI_ERROR_INV_SIZE          : ("VI_ERROR_INV_SIZE",
                                  "Invalid size of window specified."),
    VI_ERROR_WINDOW_MAPPED     : ("VI_ERROR_WINDOW_MAPPED",
                                  "The specified session currently contains "
                                  "a mapped window."),
    VI_ERROR_NIMPL_OPER        : ("VI_ERROR_NIMPL_OPER",
                                  "The given operation is not implemented."),
    VI_ERROR_INV_LENGTH        : ("VI_ERROR_INV_LENGTH",
                                  "Invalid length specified."),
    VI_ERROR_INV_MODE          : ("VI_ERROR_INV_MODE",
                                  "Invalid mode specified."),
    VI_ERROR_SESN_NLOCKED      : ("VI_ERROR_SESN_NLOCKED",
                                  "The current session did not have a lock "
                                  "on the resource."),
    VI_ERROR_MEM_NSHARED       : ("VI_ERROR_MEM_NSHARED",
                                  "The device does not export any memory."),
    VI_ERROR_LIBRARY_NFOUND    : ("VI_ERROR_LIBRARY_NFOUND",
                                  "A code library required by VISA could not "
                                  "be located or loaded."),
    VI_ERROR_NSUP_INTR         : ("VI_ERROR_NSUP_INTR",
                                  "The interface cannot generate an "
                                  "interrupt on the requested level or with "
                                  "the requested statusID value."),
    VI_ERROR_INV_LINE          : ("VI_ERROR_INV_LINE",
                                  "The value specified by the line parameter "
                                  "is invalid."),
    VI_ERROR_FILE_ACCESS       : ("VI_ERROR_FILE_ACCESS",
                                  "An error occurred while trying to open "
                                  "the specified file. Possible reasons "
                                  "include an invalid path or lack of access "
                                  "rights."),
    VI_ERROR_FILE_IO           : ("VI_ERROR_FILE_IO",
                                  "An error occurred while performing I/O on "
                                  "the specified file."),
    VI_ERROR_NSUP_LINE         : ("VI_ERROR_NSUP_LINE",
                                  "One of the specified lines (trigSrc or "
                                  "trigDest) is not supported by this VISA "
                                  "implementation, or the combination of "
                                  "lines is not a valid mapping."),
    VI_ERROR_NSUP_MECH         : ("VI_ERROR_NSUP_MECH",
                                  "The specified mechanism is not supported "
                                  "for the given event type."),
    VI_ERROR_INTF_NUM_NCONFIG  : ("VI_ERROR_INTF_NUM_NCONFIG",
                                  "The interface type is valid but the "
                                  "specified interface number is not "
                                  "configured."),
    VI_ERROR_CONN_LOST         : ("VI_ERROR_CONN_LOST",
                                  "The connection for the given session has "
                                  "been lost."),
    VI_ERROR_MACHINE_NAVAIL    : ("VI_ERROR_MACHINE_NAVAIL",
                                  "The remote machine does not exist or is "
                                  "not accepting any connections. If the "
                                  "NI-VISA server is installed and running "
                                  "on the remote machine, it may have an "
                                  "incompatible version or may be listening "
                                  "on a different port."),
    VI_ERROR_NPERMISSION       : ("VI_ERROR_NPERMISSION",
                                  "Access to the resource or remote machine "
                                  "is denied. This is due to lack of "
                                  "sufficient privileges for the current "
                                  "user or machine")
}


default_warnings = frozenset([VI_SUCCESS_MAX_CNT, VI_SUCCESS_DEV_NPRESENT,
                              VI_SUCCESS_SYNC, VI_WARN_QUEUE_OVERFLOW,
                              VI_WARN_CONFIG_NLOADED, VI_WARN_NULL_OBJECT,
                              VI_WARN_NSUP_ATTR_STATE, VI_WARN_UNKNOWN_STATUS,
                              VI_WARN_NSUP_BUF, VI_WARN_EXT_FUNC_NIMPL])


class Error(Exception):
    """Abstract basic exception class for this module."""

    def __init__(self, description):
        super(Error, self).__init__(description)
        
    def __eq__(self, other):
        return self.__dict__ == other.__dict__


class VisaIOError(Error):
    """Exception class for VISA I/O errors.

    Please note that all values for "error_code" are negative according to the
    specification (VPP-4.3.2, observation 3.3.2) and the NI implementation.

    """

    def __init__(self, error_code):
        abbreviation, description = completion_and_error_messages.get(error_code,
                                                                      ('?', 'Unknown code.'))
        super(VisaIOError, self).__init__('%s (%d): %s' % (abbreviation, error_code, description))
        self.error_code = error_code
        self.abbreviation = abbreviation
        self.description = description
        
    def __reduce__(self):
        return (VisaIOError, (self.error_code,))


class VisaIOWarning(Warning):
    """Exception class for VISA I/O warnings.

    According to the specification VPP-4.3.2 and the NI implementation.

    """

    def __init__(self, error_code):
        abbreviation, description = completion_and_error_messages.get(error_code,
                                                                      ('?', 'Unknown code.'))
        super(VisaIOWarning, self).__init__('%s (%d): %s' % (abbreviation, error_code, description))
        self.error_code = error_code
        self.abbreviation = abbreviation
        self.description = description
        
    def __reduce__(self):
        return (VisaIOWarning, (self.error_code,))
        
    def __eq__(self, other):
        return self.__dict__ == other.__dict__


class VisaTypeError(Error):
    """Exception class for wrong types in VISA function argument lists.

    Raised if unsupported types are given to scanf, sscanf, printf, sprintf,
    and queryf.  Because the current implementation doesn't analyse the format
    strings, it can only deal with integers, floats, and strings.

    Additionally, this exception is raised by install_handler if un unsupported
    type is used for the user handle.

    """


class UnknownHandler(Error):
    """Exception class for invalid handler data given to uninstall_handler().

    uninstall_handler() checks whether the handler and user_data parameters
    point to a known handler previously installed with install_handler().  If
    it can't find it, this exception is raised.

    """

    def __init__(self, event_type, handler, user_handle):
        super(UnknownHandler, self).__init__('%s, %s, %s' % (event_type, handler, user_handle))
        self.event_type = event_type
        self.handler = handler
        self.user_handle = user_handle
        
    def __reduce__(self):
        return (UnknownHandler, (self.event_type, self.handler, self.user_handle))


class OSNotSupported(Error):

    def __init__(self, os):
        super(OSNotSupported, self).__init__(os + " is not yet supported by PyVISA")
        self.os = os
        
    def __reduce__(self):
        return (OSNotSupported, (self.os,))


class InvalidBinaryFormat(Error):

    def __init__(self, description=""):
        if description:
            description = ": " + description
        super(InvalidBinaryFormat, self).__init__("Unrecognized binary data format" + description)
        self.description = description

    def __reduce__(self):
        return (InvalidBinaryFormat, (self.description,))        


class InvalidSession(Error):
    """Exception raised when an invalid session is requested.
    """

    def __init__(self):
        super(InvalidSession, self).__init__('Invalid session handle. The resource might be closed.')

    def __reduce__(self):
        return (InvalidSession, ())


class LibraryError(OSError, Error):

    @classmethod
    def from_exception(cls, exc, filename):

        try:
            msg = str(exc)

            if ': image not found' in msg:
                msg = ' File not found or not readable.'

            elif ': no suitable image found' in msg:
                if 'no matching architecture' in msg:
                    return LibraryError.from_wrong_arch(filename)
                else:
                    msg = 'Could not determine filetype.'

            elif 'wrong ELF class' in msg:
                return LibraryError.from_wrong_arch(filename)
        except UnicodeDecodeError:
            return cls('Error while accessing %s:' % filename)

        return cls('Error while accessing %s: %s' % (filename, msg))

    @classmethod
    def from_wrong_arch(cls, filename):
        s = ''
        details = util.get_system_details(backends=False)
        visalib = util.LibraryPath(filename, 'user' if filename == util.read_user_library_path() else 'auto')
        s += 'No matching architecture.\n'
        s += '    Current Python interpreter is %s bits\n' % details['bits']
        s += '    The library in: %s\n' % visalib.path
        s += '      found by: %s\n' % visalib.found_by
        s += '      bitness: %s\n' % visalib.bitness

        return cls('Error while accessing %s: %s' % (filename, s))


def _args_to_str(args, kwargs):
    return 'args=%s, kwargs=%s' % (args, kwargs)


def return_handler(module_logger, first_is_session=True):
    """Decorator for VISA library classes.
    """

    def _outer(visa_library_method):

        def _inner(self, session, *args, **kwargs):

            ret_value = visa_library_method(*args, **kwargs)
            module_logger.debug('%s%s -> %r',
                                visa_library_method.__name__,
                                _args_to_str(args, kwargs),
                                ret_value)

            try:
                ret_value = constants.StatusCode(ret_value)
            except ValueError:
                pass

            if first_is_session:
                self._last_status = ret_value
                self._last_status_in_session[session] = ret_value

            if ret_value < 0:
                raise VisaIOError(ret_value)

            if ret_value in self.issue_warning_on:
                if session and ret_value not in self._ignore_warning_in_session[session]:
                    module_logger.warn(VisaIOWarning(ret_value), stacklevel=2)

            return ret_value

        return _inner

    return _outer