#!/usr/bin/env python3
# group: rw backing
#
# Tests for drive-backup
#
# Copyright (C) 2013 Red Hat, Inc.
#
# Based on 041.
#
# 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, see <http://www.gnu.org/licenses/>.
#

import time
import os
import iotests
from iotests import qemu_img, qemu_io, create_image

backing_img = os.path.join(iotests.test_dir, 'backing.img')
test_img = os.path.join(iotests.test_dir, 'test.img')
target_img = os.path.join(iotests.test_dir, 'target.img')

def img_create(img, fmt=iotests.imgfmt, size='64M', **kwargs):
    fullname = os.path.join(iotests.test_dir, '%s.%s' % (img, fmt))
    optargs = []
    for k,v in kwargs.items():
        optargs = optargs + ['-o', '%s=%s' % (k,v)]
    args = ['create', '-f', fmt] + optargs + [fullname, size]
    iotests.qemu_img(*args)
    return fullname

def try_remove(img):
    try:
        os.remove(img)
    except OSError:
        pass

def io_write_patterns(img, patterns):
    for pattern in patterns:
        iotests.qemu_io('-c', 'write -P%s %s %s' % pattern, img)


class TestSyncModesNoneAndTop(iotests.QMPTestCase):
    image_len = 64 * 1024 * 1024 # MB

    def setUp(self):
        create_image(backing_img, TestSyncModesNoneAndTop.image_len)
        qemu_img('create', '-f', iotests.imgfmt,
                 '-o', 'backing_file=%s' % backing_img, '-F', 'raw', test_img)
        qemu_io('-c', 'write -P0x41 0 512', test_img)
        qemu_io('-c', 'write -P0xd5 1M 32k', test_img)
        qemu_io('-c', 'write -P0xdc 32M 124k', test_img)
        qemu_io('-c', 'write -P0xdc 67043328 64k', test_img)
        self.vm = iotests.VM().add_drive(test_img)
        self.vm.launch()

    def tearDown(self):
        self.vm.shutdown()
        os.remove(test_img)
        os.remove(backing_img)
        try:
            os.remove(target_img)
        except OSError:
            pass

    def test_complete_top(self):
        self.assert_no_active_block_jobs()
        self.vm.cmd('drive-backup', device='drive0', sync='top',
                    format=iotests.imgfmt, target=target_img)

        self.wait_until_completed(check_offset=False)

        self.assert_no_active_block_jobs()
        self.vm.shutdown()
        self.assertTrue(iotests.compare_images(test_img, target_img),
                        'target image does not match source after backup')

    def test_cancel_sync_none(self):
        self.assert_no_active_block_jobs()

        self.vm.cmd('drive-backup', device='drive0',
                    sync='none', target=target_img)
        time.sleep(1)
        self.vm.hmp_qemu_io('drive0', 'write -P0x5e 0 512')
        self.vm.hmp_qemu_io('drive0', 'aio_flush')
        # Verify that the original contents exist in the target image.

        event = self.cancel_and_wait()
        self.assert_qmp(event, 'data/type', 'backup')

        self.vm.shutdown()
        time.sleep(1)
        qemu_io('-c', 'read -P0x41 0 512', target_img)

class TestBeforeWriteNotifier(iotests.QMPTestCase):
    def setUp(self):
        self.vm = iotests.VM().add_drive_raw("file=blkdebug::null-co://,id=drive0,align=65536,driver=blkdebug")
        self.vm.launch()

    def tearDown(self):
        self.vm.shutdown()
        os.remove(target_img)

    def test_before_write_notifier(self):
        self.vm.pause_drive("drive0")
        self.vm.cmd('drive-backup', device='drive0',
                    sync='full', target=target_img,
                    format="file", speed=1)
        self.vm.cmd('block-job-pause', device="drive0")
        # Speed is low enough that this must be an uncopied range, which will
        # trigger the before write notifier
        self.vm.hmp_qemu_io('drive0', 'aio_write -P 1 512512 512')
        self.vm.resume_drive("drive0")
        self.vm.cmd('block-job-resume', device="drive0")
        event = self.cancel_and_wait()
        self.assert_qmp(event, 'data/type', 'backup')

class BackupTest(iotests.QMPTestCase):
    def setUp(self):
        self.vm = iotests.VM()
        self.test_img = img_create('test')
        self.dest_img = img_create('dest')
        self.dest_img2 = img_create('dest2')
        self.ref_img = img_create('ref')
        self.vm.add_drive(self.test_img)
        self.vm.launch()

    def tearDown(self):
        self.vm.shutdown()
        try_remove(self.test_img)
        try_remove(self.dest_img)
        try_remove(self.dest_img2)
        try_remove(self.ref_img)

    def hmp_io_writes(self, drive, patterns):
        for pattern in patterns:
            self.vm.hmp_qemu_io(drive, 'write -P%s %s %s' % pattern)
        self.vm.hmp_qemu_io(drive, 'flush')

    def qmp_backup_and_wait(self, cmd='drive-backup', serror=None,
                            aerror=None, **kwargs):
        if not self.qmp_backup(cmd, serror, **kwargs):
            return False
        return self.qmp_backup_wait(kwargs['device'], aerror)

    def qmp_backup(self, cmd='drive-backup',
                   error=None, **kwargs):
        self.assertTrue('device' in kwargs)
        res = self.vm.qmp(cmd, **kwargs)
        if error:
            self.assert_qmp(res, 'error/desc', error)
            return False
        self.assert_qmp(res, 'return', {})
        return True

    def qmp_backup_wait(self, device, error=None):
        event = self.vm.event_wait(name="BLOCK_JOB_COMPLETED",
                                   match={'data': {'device': device}})
        self.assertNotEqual(event, None)
        try:
            failure = self.dictpath(event, 'data/error')
        except AssertionError:
            # Backup succeeded.
            self.assert_qmp(event, 'data/offset', event['data']['len'])
            return True
        else:
            # Failure.
            self.assert_qmp(event, 'data/error', qerror)
            return False

    def test_overlapping_writes(self):
        # Write something to back up
        self.hmp_io_writes('drive0', [('42', '0M', '2M')])

        # Create a reference backup
        self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
                                 sync='full', target=self.ref_img,
                                 auto_dismiss=False)
        self.vm.cmd('block-job-dismiss', id='drive0')

        # Now to the test backup: We simulate the following guest
        # writes:
        # (1) [1M + 64k, 1M + 128k): Afterwards, everything in that
        #     area should be in the target image, and we must not copy
        #     it again (because the source image has changed now)
        #     (64k is the job's cluster size)
        # (2) [1M, 2M): The backup job must not get overeager.  It
        #     must copy [1M, 1M + 64k) and [1M + 128k, 2M) separately,
        #     but not the area in between.

        self.qmp_backup(device='drive0', format=iotests.imgfmt, sync='full',
                        target=self.dest_img, speed=1, auto_dismiss=False)

        self.hmp_io_writes('drive0', [('23', '%ik' % (1024 + 64), '64k'),
                                      ('66', '1M', '1M')])

        # Let the job complete
        self.vm.cmd('block-job-set-speed', device='drive0', speed=0)
        self.qmp_backup_wait('drive0')
        self.vm.cmd('block-job-dismiss', id='drive0')

        self.assertTrue(iotests.compare_images(self.ref_img, self.dest_img),
                        'target image does not match reference image')

    def test_dismiss_false(self):
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
                                 sync='full', target=self.dest_img,
                                 auto_dismiss=True)
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])

    def test_dismiss_true(self):
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
                                 sync='full', target=self.dest_img,
                                 auto_dismiss=False)
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return[0]/status', 'concluded')
        self.vm.cmd('block-job-dismiss', id='drive0')
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])

    def test_dismiss_bad_id(self):
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        res = self.vm.qmp('block-job-dismiss', id='foobar')
        self.assert_qmp(res, 'error/class', 'DeviceNotActive')

    def test_dismiss_collision(self):
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
                                 sync='full', target=self.dest_img,
                                 auto_dismiss=False)
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return[0]/status', 'concluded')
        # Leave zombie job un-dismissed, observe a failure:
        res = self.qmp_backup_and_wait(serror="Job ID 'drive0' already in use",
                                       device='drive0', format=iotests.imgfmt,
                                       sync='full', target=self.dest_img2,
                                       auto_dismiss=False)
        self.assertEqual(res, False)
        # OK, dismiss the zombie.
        self.vm.cmd('block-job-dismiss', id='drive0')
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        # Ensure it's really gone.
        self.qmp_backup_and_wait(device='drive0', format=iotests.imgfmt,
                                 sync='full', target=self.dest_img2,
                                 auto_dismiss=False)

    def dismissal_failure(self, dismissal_opt):
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return', [])
        # Give blkdebug something to chew on
        self.hmp_io_writes('drive0',
                           (('0x9a', 0, 512),
                           ('0x55', '8M', '352k'),
                           ('0x78', '15872k', '1M')))
        # Add destination node via blkdebug
        self.vm.cmd('blockdev-add',
                    node_name='target0',
                    driver=iotests.imgfmt,
                    file={
                        'driver': 'blkdebug',
                        'image': {
                            'driver': 'file',
                            'filename': self.dest_img
                        },
                        'inject-error': [{
                            'event': 'write_aio',
                            'errno': 5,
                            'immediately': False,
                            'once': True
                        }],
                    })

        res = self.qmp_backup(cmd='blockdev-backup',
                              device='drive0', target='target0',
                              on_target_error='stop',
                              sync='full',
                              auto_dismiss=dismissal_opt)
        self.assertTrue(res)
        event = self.vm.event_wait(name="BLOCK_JOB_ERROR",
                                   match={'data': {'device': 'drive0'}})
        self.assertNotEqual(event, None)
        # OK, job should pause, but it can't do it immediately, as it can't
        # cancel other parallel requests (which didn't fail)
        with iotests.Timeout(60, "Timeout waiting for backup actually paused"):
            while True:
                res = self.vm.qmp('query-block-jobs')
                if res['return'][0]['status'] == 'paused':
                    break
        self.assert_qmp(res, 'return[0]/status', 'paused')
        res = self.vm.qmp('block-job-dismiss', id='drive0')
        self.assert_qmp(res, 'error/desc',
                        "Job 'drive0' in state 'paused' cannot accept"
                        " command verb 'dismiss'")
        res = self.vm.qmp('query-block-jobs')
        self.assert_qmp(res, 'return[0]/status', 'paused')
        # OK, unstick job and move forward.
        self.vm.cmd('block-job-resume', device='drive0')
        # And now we need to wait for it to conclude;
        res = self.qmp_backup_wait(device='drive0')
        self.assertTrue(res)
        if not dismissal_opt:
            # Job should now be languishing:
            res = self.vm.qmp('query-block-jobs')
            self.assert_qmp(res, 'return[0]/status', 'concluded')
            self.vm.cmd('block-job-dismiss', id='drive0')
            res = self.vm.qmp('query-block-jobs')
            self.assert_qmp(res, 'return', [])

    def test_dismiss_premature(self):
        self.dismissal_failure(False)

    def test_dismiss_erroneous(self):
        self.dismissal_failure(True)

if __name__ == '__main__':
    iotests.main(supported_fmts=['qcow2', 'qed'],
                 supported_protocols=['file'])