#!/usr/bin/env python3
#
#  Copyright (c) 2017 Red Hat Inc
#
# Author:
#  Eduardo Habkost <ehabkost@redhat.com>
#
# 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.

"""
Run QEMU with all combinations of -machine and -device types,
check for crashes and unexpected errors.
"""

import os
import sys
import glob
import logging
import traceback
import re
import random
import argparse
from itertools import chain

sys.path.append(os.path.join(os.path.dirname(__file__), '..', 'python'))
from qemu.machine import QEMUMachine

logger = logging.getLogger('device-crash-test')
dbg = logger.debug


# Purposes of the following whitelist:
# * Avoiding verbose log messages when we find known non-fatal
#   (exitcode=1) errors
# * Avoiding fatal errors when we find known crashes
# * Skipping machines/devices that are known not to work out of
#   the box, when running in --quick mode
#
# Keeping the whitelist updated is desirable, but not required,
# because unexpected cases where QEMU exits with exitcode=1 will
# just trigger a INFO message.

# Valid whitelist entry keys:
# * accel: regexp, full match only
# * machine: regexp, full match only
# * device: regexp, full match only
# * log: regexp, partial match allowed
# * exitcode: if not present, defaults to 1. If None, matches any exitcode
# * warn: if True, matching failures will be logged as warnings
# * expected: if True, QEMU is expected to always fail every time
#   when testing the corresponding test case
# * loglevel: log level of log output when there's a match.
ERROR_WHITELIST = [
    # Machines that won't work out of the box:
    #             MACHINE                         | ERROR MESSAGE
    {'machine':'niagara', 'expected':True},       # Unable to load a firmware for -M niagara
    {'machine':'boston', 'expected':True},        # Please provide either a -kernel or -bios argument
    {'machine':'leon3_generic', 'expected':True}, # Can't read bios image (null)

    # devices that don't work out of the box because they require extra options to "-device DEV":
    #            DEVICE                                    | ERROR MESSAGE
    {'device':'.*-(i386|x86_64)-cpu', 'expected':True},    # CPU socket-id is not set
    {'device':'icp', 'expected':True},                     # icp_realize: required link 'xics' not found: Property '.xics' not found
    {'device':'ics', 'expected':True},                     # ics_base_realize: required link 'xics' not found: Property '.xics' not found
    # "-device ide-cd" does work on more recent QEMU versions, so it doesn't have expected=True
    {'device':'ide-cd'},                                 # No drive specified
    {'device':'ide-drive', 'expected':True},               # No drive specified
    {'device':'ide-hd', 'expected':True},                  # No drive specified
    {'device':'ipmi-bmc-extern', 'expected':True},         # IPMI external bmc requires chardev attribute
    {'device':'isa-debugcon', 'expected':True},            # Can't create serial device, empty char device
    {'device':'isa-ipmi-bt', 'expected':True},             # IPMI device requires a bmc attribute to be set
    {'device':'isa-ipmi-kcs', 'expected':True},            # IPMI device requires a bmc attribute to be set
    {'device':'isa-parallel', 'expected':True},            # Can't create serial device, empty char device
    {'device':'ivshmem-doorbell', 'expected':True},        # You must specify a 'chardev'
    {'device':'ivshmem-plain', 'expected':True},           # You must specify a 'memdev'
    {'device':'loader', 'expected':True},                  # please include valid arguments
    {'device':'nand', 'expected':True},                    # Unsupported NAND block size 0x1
    {'device':'nvdimm', 'expected':True},                  # 'memdev' property is not set
    {'device':'nvme', 'expected':True},                    # Device initialization failed
    {'device':'pc-dimm', 'expected':True},                 # 'memdev' property is not set
    {'device':'pci-bridge', 'expected':True},              # Bridge chassis not specified. Each bridge is required to be assigned a unique chassis id > 0.
    {'device':'pci-bridge-seat', 'expected':True},         # Bridge chassis not specified. Each bridge is required to be assigned a unique chassis id > 0.
    {'device':'pxb', 'expected':True},                     # Bridge chassis not specified. Each bridge is required to be assigned a unique chassis id > 0.
    {'device':'scsi-block', 'expected':True},              # drive property not set
    {'device':'scsi-disk', 'expected':True},               # drive property not set
    {'device':'scsi-generic', 'expected':True},            # drive property not set
    {'device':'scsi-hd', 'expected':True},                 # drive property not set
    {'device':'spapr-pci-host-bridge', 'expected':True},   # BUID not specified for PHB
    {'device':'spapr-rng', 'expected':True},               # spapr-rng needs an RNG backend!
    {'device':'spapr-vty', 'expected':True},               # chardev property not set
    {'device':'tpm-tis', 'expected':True},                 # tpm_tis: backend driver with id (null) could not be found
    {'device':'unimplemented-device', 'expected':True},    # property 'size' not specified or zero
    {'device':'usb-braille', 'expected':True},             # Property chardev is required
    {'device':'usb-mtp', 'expected':True},                 # rootdir property must be configured
    {'device':'usb-redir', 'expected':True},               # Parameter 'chardev' is missing
    {'device':'usb-serial', 'expected':True},              # Property chardev is required
    {'device':'usb-storage', 'expected':True},             # drive property not set
    {'device':'vfio-amd-xgbe', 'expected':True},           # -device vfio-amd-xgbe: vfio error: wrong host device name
    {'device':'vfio-calxeda-xgmac', 'expected':True},      # -device vfio-calxeda-xgmac: vfio error: wrong host device name
    {'device':'vfio-pci', 'expected':True},                # No provided host device
    {'device':'vfio-pci-igd-lpc-bridge', 'expected':True}, # VFIO dummy ISA/LPC bridge must have address 1f.0
    {'device':'vhost-scsi.*', 'expected':True},            # vhost-scsi: missing wwpn
    {'device':'vhost-vsock-device', 'expected':True},      # guest-cid property must be greater than 2
    {'device':'vhost-vsock-pci', 'expected':True},         # guest-cid property must be greater than 2
    {'device':'virtio-9p-ccw', 'expected':True},           # 9pfs device couldn't find fsdev with the id = NULL
    {'device':'virtio-9p-device', 'expected':True},        # 9pfs device couldn't find fsdev with the id = NULL
    {'device':'virtio-9p-pci', 'expected':True},           # 9pfs device couldn't find fsdev with the id = NULL
    {'device':'virtio-blk-ccw', 'expected':True},          # drive property not set
    {'device':'virtio-blk-device', 'expected':True},       # drive property not set
    {'device':'virtio-blk-device', 'expected':True},       # drive property not set
    {'device':'virtio-blk-pci', 'expected':True},          # drive property not set
    {'device':'virtio-crypto-ccw', 'expected':True},       # 'cryptodev' parameter expects a valid object
    {'device':'virtio-crypto-device', 'expected':True},    # 'cryptodev' parameter expects a valid object
    {'device':'virtio-crypto-pci', 'expected':True},       # 'cryptodev' parameter expects a valid object
    {'device':'virtio-input-host-device', 'expected':True}, # evdev property is required
    {'device':'virtio-input-host-pci', 'expected':True},   # evdev property is required
    {'device':'xen-pvdevice', 'expected':True},            # Device ID invalid, it must always be supplied
    {'device':'vhost-vsock-ccw', 'expected':True},         # guest-cid property must be greater than 2
    {'device':'zpci', 'expected':True},                    # target must be defined
    {'device':'pnv-(occ|icp|lpc)', 'expected':True},       # required link 'xics' not found: Property '.xics' not found
    {'device':'powernv-cpu-.*', 'expected':True},          # pnv_core_realize: required link 'xics' not found: Property '.xics' not found

    # ioapic devices are already created by pc and will fail:
    {'machine':'q35|pc.*', 'device':'kvm-ioapic', 'expected':True}, # Only 1 ioapics allowed
    {'machine':'q35|pc.*', 'device':'ioapic', 'expected':True},     # Only 1 ioapics allowed

    # "spapr-cpu-core needs a pseries machine"
    {'machine':'(?!pseries).*', 'device':'.*-spapr-cpu-core', 'expected':True},

    # KVM-specific devices shouldn't be tried without accel=kvm:
    {'accel':'(?!kvm).*', 'device':'kvmclock', 'expected':True},

    # xen-specific machines and devices:
    {'accel':'(?!xen).*', 'machine':'xen.*', 'expected':True},
    {'accel':'(?!xen).*', 'device':'xen-.*', 'expected':True},

    # this fails on some machine-types, but not all, so they don't have expected=True:
    {'device':'vmgenid'}, # vmgenid requires DMA write support in fw_cfg, which this machine type does not provide

    # Silence INFO messages for errors that are common on multiple
    # devices/machines:
    {'log':r"No '[\w-]+' bus found for device '[\w-]+'"},
    {'log':r"images* must be given with the 'pflash' parameter"},
    {'log':r"(Guest|ROM|Flash|Kernel) image must be specified"},
    {'log':r"[cC]ould not load [\w ]+ (BIOS|bios) '[\w-]+\.bin'"},
    {'log':r"Couldn't find rom image '[\w-]+\.bin'"},
    {'log':r"speed mismatch trying to attach usb device"},
    {'log':r"Can't create a second ISA bus"},
    {'log':r"duplicate fw_cfg file name"},
    # sysbus-related error messages: most machines reject most dynamic sysbus devices:
    {'log':r"Option '-device [\w.,-]+' cannot be handled by this machine"},
    {'log':r"Device [\w.,-]+ is not supported by this machine yet"},
    {'log':r"Device [\w.,-]+ can not be dynamically instantiated"},
    {'log':r"Platform Bus: Can not fit MMIO region of size "},
    # other more specific errors we will ignore:
    {'device':'.*-spapr-cpu-core', 'log':r"CPU core type should be"},
    {'log':r"MSI(-X)? is not supported by interrupt controller"},
    {'log':r"pxb-pcie? devices cannot reside on a PCIe? bus"},
    {'log':r"Ignoring smp_cpus value"},
    {'log':r"sd_init failed: Drive 'sd0' is already in use because it has been automatically connected to another device"},
    {'log':r"This CPU requires a smaller page size than the system is using"},
    {'log':r"MSI-X support is mandatory in the S390 architecture"},
    {'log':r"rom check and register reset failed"},
    {'log':r"Unable to initialize GIC, CPUState for CPU#0 not valid"},
    {'log':r"Multiple VT220 operator consoles are not supported"},
    {'log':r"core 0 already populated"},
    {'log':r"could not find stage1 bootloader"},

    # other exitcode=1 failures not listed above will just generate INFO messages:
    {'exitcode':1, 'loglevel':logging.INFO},

    # everything else (including SIGABRT and SIGSEGV) will be a fatal error:
    {'exitcode':None, 'fatal':True, 'loglevel':logging.FATAL},
]


def whitelistTestCaseMatch(wl, t):
    """Check if a test case specification can match a whitelist entry

    This only checks if a whitelist entry is a candidate match
    for a given test case, it won't check if the test case
    results/output match the entry.  See whitelistResultMatch().
    """
    return (('machine' not in wl or
             'machine' not in t or
             re.match(wl['machine'] + '$', t['machine'])) and
            ('accel' not in wl or
             'accel' not in t or
             re.match(wl['accel'] + '$', t['accel'])) and
            ('device' not in wl or
             'device' not in t or
             re.match(wl['device'] + '$', t['device'])))


def whitelistCandidates(t):
    """Generate the list of candidates that can match a test case"""
    for i, wl in enumerate(ERROR_WHITELIST):
        if whitelistTestCaseMatch(wl, t):
            yield (i, wl)


def findExpectedResult(t):
    """Check if there's an expected=True whitelist entry for a test case

    Returns (i, wl) tuple, where i is the index in
    ERROR_WHITELIST and wl is the whitelist entry itself.
    """
    for i, wl in whitelistCandidates(t):
        if wl.get('expected'):
            return (i, wl)


def whitelistResultMatch(wl, r):
    """Check if test case results/output match a whitelist entry

    It is valid to call this function only if
    whitelistTestCaseMatch() is True for the entry (e.g. on
    entries returned by whitelistCandidates())
    """
    assert whitelistTestCaseMatch(wl, r['testcase'])
    return ((wl.get('exitcode', 1) is None or
             r['exitcode'] == wl.get('exitcode', 1)) and
            ('log' not in wl or
             re.search(wl['log'], r['log'], re.MULTILINE)))


def checkResultWhitelist(r):
    """Look up whitelist entry for a given test case result

    Returns (i, wl) tuple, where i is the index in
    ERROR_WHITELIST and wl is the whitelist entry itself.
    """
    for i, wl in whitelistCandidates(r['testcase']):
        if whitelistResultMatch(wl, r):
            return i, wl

    raise Exception("this should never happen")


def qemuOptsEscape(s):
    """Escape option value QemuOpts"""
    return s.replace(",", ",,")


def formatTestCase(t):
    """Format test case info as "key=value key=value" for prettier logging output"""
    return ' '.join('%s=%s' % (k, v) for k, v in t.items())


def qomListTypeNames(vm, **kwargs):
    """Run qom-list-types QMP command, return type names"""
    types = vm.command('qom-list-types', **kwargs)
    return [t['name'] for t in types]


def infoQDM(vm):
    """Parse 'info qdm' output"""
    args = {'command-line': 'info qdm'}
    devhelp = vm.command('human-monitor-command', **args)
    for l in devhelp.split('\n'):
        l = l.strip()
        if l == '' or l.endswith(':'):
            continue
        d = {'name': re.search(r'name "([^"]+)"', l).group(1),
             'no-user': (re.search(', no-user', l) is not None)}
        yield d


class QemuBinaryInfo(object):
    def __init__(self, binary, devtype):
        if devtype is None:
            devtype = 'device'

        self.binary = binary
        self._machine_info = {}

        dbg("devtype: %r", devtype)
        args = ['-S', '-machine', 'none,accel=kvm:tcg']
        dbg("querying info for QEMU binary: %s", binary)
        vm = QEMUMachine(binary=binary, args=args)
        vm.launch()
        try:
            self.alldevs = set(qomListTypeNames(vm, implements=devtype, abstract=False))
            # there's no way to query DeviceClass::user_creatable using QMP,
            # so use 'info qdm':
            self.no_user_devs = set([d['name'] for d in infoQDM(vm, ) if d['no-user']])
            self.machines = list(m['name'] for m in vm.command('query-machines'))
            self.user_devs = self.alldevs.difference(self.no_user_devs)
            self.kvm_available = vm.command('query-kvm')['enabled']
        finally:
            vm.shutdown()

    def machineInfo(self, machine):
        """Query for information on a specific machine-type

        Results are cached internally, in case the same machine-
        type is queried multiple times.
        """
        if machine in self._machine_info:
            return self._machine_info[machine]

        mi = {}
        args = ['-S', '-machine', '%s' % (machine)]
        dbg("querying machine info for binary=%s machine=%s", self.binary, machine)
        vm = QEMUMachine(binary=self.binary, args=args)
        try:
            vm.launch()
            mi['runnable'] = True
        except KeyboardInterrupt:
            raise
        except:
            dbg("exception trying to run binary=%s machine=%s", self.binary, machine, exc_info=sys.exc_info())
            dbg("log: %r", vm.get_log())
            mi['runnable'] = False

        vm.shutdown()
        self._machine_info[machine] = mi
        return mi


BINARY_INFO = {}


def getBinaryInfo(args, binary):
    if binary not in BINARY_INFO:
        BINARY_INFO[binary] = QemuBinaryInfo(binary, args.devtype)
    return BINARY_INFO[binary]


def checkOneCase(args, testcase):
    """Check one specific case

    Returns a dictionary containing failure information on error,
    or None on success
    """
    binary = testcase['binary']
    accel = testcase['accel']
    machine = testcase['machine']
    device = testcase['device']

    dbg("will test: %r", testcase)

    args = ['-S', '-machine', '%s,accel=%s' % (machine, accel),
            '-device', qemuOptsEscape(device)]
    cmdline = ' '.join([binary] + args)
    dbg("will launch QEMU: %s", cmdline)
    vm = QEMUMachine(binary=binary, args=args)

    exc_traceback = None
    try:
        vm.launch()
    except KeyboardInterrupt:
        raise
    except:
        exc_traceback = traceback.format_exc()
        dbg("Exception while running test case")
    finally:
        vm.shutdown()
        ec = vm.exitcode()
        log = vm.get_log()

    if exc_traceback is not None or ec != 0:
        return {'exc_traceback':exc_traceback,
                'exitcode':ec,
                'log':log,
                'testcase':testcase,
                'cmdline':cmdline}


def binariesToTest(args, testcase):
    if args.qemu:
        r = args.qemu
    else:
        r = glob.glob('./qemu-system-*')
    return r


def accelsToTest(args, testcase):
    if getBinaryInfo(args, testcase['binary']).kvm_available:
        yield 'kvm'
    yield 'tcg'


def machinesToTest(args, testcase):
    return getBinaryInfo(args, testcase['binary']).machines


def devicesToTest(args, testcase):
    return getBinaryInfo(args, testcase['binary']).user_devs


TESTCASE_VARIABLES = [
    ('binary', binariesToTest),
    ('accel', accelsToTest),
    ('machine', machinesToTest),
    ('device', devicesToTest),
]


def genCases1(args, testcases, var, fn):
    """Generate new testcases for one variable

    If an existing item already has a variable set, don't
    generate new items and just return it directly. This
    allows the "-t" command-line option to be used to choose
    a specific test case.
    """
    for testcase in testcases:
        if var in testcase:
            yield testcase.copy()
        else:
            for i in fn(args, testcase):
                t = testcase.copy()
                t[var] = i
                yield t


def genCases(args, testcase):
    """Generate test cases for all variables
    """
    cases = [testcase.copy()]
    for var, fn in TESTCASE_VARIABLES:
        dbg("var: %r, fn: %r", var, fn)
        cases = genCases1(args, cases, var, fn)
    return cases


def casesToTest(args, testcase):
    cases = genCases(args, testcase)
    if args.random:
        cases = list(cases)
        cases = random.sample(cases, min(args.random, len(cases)))
    if args.debug:
        cases = list(cases)
        dbg("%d test cases to test", len(cases))
    if args.shuffle:
        cases = list(cases)
        random.shuffle(cases)
    return cases


def logFailure(f, level):
    t = f['testcase']
    logger.log(level, "failed: %s", formatTestCase(t))
    logger.log(level, "cmdline: %s", f['cmdline'])
    for l in f['log'].strip().split('\n'):
        logger.log(level, "log: %s", l)
    logger.log(level, "exit code: %r", f['exitcode'])
    if f['exc_traceback']:
        logger.log(level, "exception:")
        for l in f['exc_traceback'].split('\n'):
            logger.log(level, "  %s", l.rstrip('\n'))


def main():
    parser = argparse.ArgumentParser(description="QEMU -device crash test")
    parser.add_argument('-t', metavar='KEY=VALUE', nargs='*',
                        help="Limit test cases to KEY=VALUE",
                        action='append', dest='testcases', default=[])
    parser.add_argument('-d', '--debug', action='store_true',
                        help='debug output')
    parser.add_argument('-v', '--verbose', action='store_true', default=True,
                        help='verbose output')
    parser.add_argument('-q', '--quiet', dest='verbose', action='store_false',
                        help='non-verbose output')
    parser.add_argument('-r', '--random', type=int, metavar='COUNT',
                        help='run a random sample of COUNT test cases',
                        default=0)
    parser.add_argument('--shuffle', action='store_true',
                        help='Run test cases in random order')
    parser.add_argument('--dry-run', action='store_true',
                        help="Don't run any tests, just generate list")
    parser.add_argument('-D', '--devtype', metavar='TYPE',
                        help="Test only device types that implement TYPE")
    parser.add_argument('-Q', '--quick', action='store_true', default=True,
                        help="Quick mode: skip test cases that are expected to fail")
    parser.add_argument('-F', '--full', action='store_false', dest='quick',
                        help="Full mode: test cases that are expected to fail")
    parser.add_argument('--strict', action='store_true', dest='strict',
                        help="Treat all warnings as fatal")
    parser.add_argument('qemu', nargs='*', metavar='QEMU',
                        help='QEMU binary to run')
    args = parser.parse_args()

    if args.debug:
        lvl = logging.DEBUG
    elif args.verbose:
        lvl = logging.INFO
    else:
        lvl = logging.WARN
    logging.basicConfig(stream=sys.stdout, level=lvl, format='%(levelname)s: %(message)s')

    fatal_failures = []
    wl_stats = {}
    skipped = 0
    total = 0

    tc = {}
    dbg("testcases: %r", args.testcases)
    if args.testcases:
        for t in chain(*args.testcases):
            for kv in t.split():
                k, v = kv.split('=', 1)
                tc[k] = v

    if len(binariesToTest(args, tc)) == 0:
        print("No QEMU binary found", file=sys.stderr)
        parser.print_usage(sys.stderr)
        return 1

    for t in casesToTest(args, tc):
        logger.info("running test case: %s", formatTestCase(t))
        total += 1

        expected_match = findExpectedResult(t)
        if (args.quick and
                (expected_match or
                 not getBinaryInfo(args, t['binary']).machineInfo(t['machine'])['runnable'])):
            dbg("skipped: %s", formatTestCase(t))
            skipped += 1
            continue

        if args.dry_run:
            continue

        try:
            f = checkOneCase(args, t)
        except KeyboardInterrupt:
            break

        if f:
            i, wl = checkResultWhitelist(f)
            dbg("testcase: %r, whitelist match: %r", t, wl)
            wl_stats.setdefault(i, []).append(f)
            level = wl.get('loglevel', logging.DEBUG)
            logFailure(f, level)
            if wl.get('fatal') or (args.strict and level >= logging.WARN):
                fatal_failures.append(f)
        else:
            dbg("success: %s", formatTestCase(t))
            if expected_match:
                logger.warn("Didn't fail as expected: %s", formatTestCase(t))

    logger.info("Total: %d test cases", total)
    if skipped:
        logger.info("Skipped %d test cases", skipped)

    if args.debug:
        stats = sorted([(len(wl_stats.get(i, [])), wl) for i, wl in
                         enumerate(ERROR_WHITELIST)], key=lambda x: x[0])
        for count, wl in stats:
            dbg("whitelist entry stats: %d: %r", count, wl)

    if fatal_failures:
        for f in fatal_failures:
            t = f['testcase']
            logger.error("Fatal failure: %s", formatTestCase(t))
        logger.error("Fatal failures on some machine/device combinations")
        return 1

if __name__ == '__main__':
    sys.exit(main())