# Copyright (c) 2015-2016 Western Digital Corporation or its affiliates.

#

# This program is free software; you can redistribute it and/or

# modify it under the terms of the GNU General Public License

# as published by the Free Software Foundation; either version 2

# of the License, or (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

# MA  02110-1301, USA.

#

#   Author: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>

#

""" Inherit TestNVMeIO for nvme read/write operations """

import os

from nose import tools

from nvme_test import TestNVMe

class TestNVMeIO(TestNVMe):

    """

    Variable and Methods required to perform nvme read/write.

        - Attributes:

              - data_size : data size to perform IO.

              - start_block : starting block of to perform IO.

              - block_count : Number of blocks to use in IO.

              - write_file : data file to use in nvme write command.

              - read_file : data file to use in nvme read command.

    """

    def __init__(self):

        """ Pre Section for TestNVMeIO """

        TestNVMe.__init__(self)

        # common code used in various testcases.

        self.data_size = 512

        self.start_block = 0

        self.block_count = 0

        self.write_file = "write_file.txt"

        self.read_file = "read_file.txt"

    def __del__(self):

        """ Post Section for TestNVMeIO """

        TestNVMe.__del__(self)

    @tools.nottest

    def create_data_file(self, pathname, data_size, pattern):

        """ Creates data file with specific pattern

            - Args:

                - pathname : data file path name.

                - data_size : total size of the data.

                - pattern : data pattern to create file.

            - Returns:

            None

        """

        pattern_len = len(pattern)

        data_file = open(pathname, "w")

        for i in range(0, data_size):

            data_file.write(pattern[i % pattern_len])

        data_file.flush()

        os.fsync(data_file.fileno())

        data_file.close()

    @tools.nottest

    def nvme_write(self):

        """ Wrapper for nvme write operation

            - Args:

                - None

            - Returns:

                - return code for nvme write command.

        """

        write_cmd = "nvme write " + self.ns1 + " --start-block=" + \

                    str(self.start_block) + " --block-count=" + \

                    str(self.block_count) + " --data-size=" + \

                    str(self.data_size) + " --data=" + self.write_file

        return self.exec_cmd(write_cmd)

    @tools.nottest

    def nvme_read(self):

        """ Wrapper for nvme read operation

            - Args:

                - None

            - Returns:

                - return code for nvme read command.

        """

        read_cmd = "nvme read " + self.ns1 + " --start-block=" + \

                   str(self.start_block) + " --block-count=" + \

                   str(self.block_count) + " --data-size=" + \

                   str(self.data_size) + " --data=" + self.read_file

        print(read_cmd)

        return self.exec_cmd(read_cmd)