testmodel.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import argparse, os, re, sys, signal, threading, psutil, subprocess, shutil, time, traceback
from asyncio.subprocess import STDOUT
try:
  import resource
except ImportError:
  resource = None
import simplejson as json
import zmq
from monotonic import monotonic
import OMPython
from OMPython import FindBestOMCSession, OMCSession, OMCSessionZMQ
import shared, glob, shlex, zipfile

parser = argparse.ArgumentParser(description='OpenModelica library testing tool helper (single model)')
parser.add_argument('config')
parser.add_argument('--ompython_omhome', default='')
parser.add_argument('--libraries')
parser.add_argument('--docker')
parser.add_argument('--dockerExtraArgs')
parser.add_argument('--corba', action="store_true", default=False)
parser.add_argument('--win', action="store_true", help="Windows mode", default=False)
parser.add_argument('--msysEnvironment', help="MSYS2 Environment (ucrt64|mingw64)", default='ucrt64')
parser.add_argument('--addmsl', action="store_true", help="add the MSL path to the OPENMODELICAPATH if the MSL is not detected in the libraries path", default=False)

args = parser.parse_args()
config = args.config
ompython_omhome = args.ompython_omhome
libraries = args.libraries.replace("\\","/")
docker = args.docker if args.docker else None
dockerExtraArgs = args.dockerExtraArgs.split(" ") if args.dockerExtraArgs else []
corbaStyle = args.corba
isWin = args.win
msysEnvironment = args.msysEnvironment
addmsl = args.addmsl

# our OMPython sessions
omc = None
omc_new = None

# add openmodelica libraries path if the Modelica libraries are not found in the libraries path
MSLpath = ''
if addmsl and len(glob.glob('Modelica *', root_dir=libraries)) == 0:
  if isWin:
    MSLpath = ';' + os.path.normpath(os.path.join(os.environ.get('APPDATA'), '.openmodelica', 'libraries')).replace('\\','/')
  else:
    MSLpath = ':' + os.path.normpath(os.path.join(os.environ.get('HOME'), '.openmodelica', 'libraries'))

try:
  os.mkdir("files")
except OSError:
  pass

class TimeoutError(Exception):
  pass

runningPhase = None
"""What is running now, as (results dict, key in it, when it started).

A command the watchdog has to kill never returns to its caller -
sendExpressionTimeout ends the process itself - so the caller's own timeout
handler does not run and the phase reports no time at all. Recording it here
instead covers every way out, because they all write the results first. The
dict is None for the model's own results, one runner's when it is its turn.
"""

def phaseStarts(key, stat=None):
  global runningPhase
  runningPhase = (stat, key, monotonic())

def phaseEnded():
  global runningPhase
  runningPhase = None

pageSize = os.sysconf("SC_PAGE_SIZE") if hasattr(os, "sysconf") else 4096

def descendants():
  """Every process below this one. /proc/<pid>/task/*/children only touches
  this tree, where psutil would scan all of /proc at every sample."""
  if isWin:
    return [p.pid for p in psutil.Process().children(recursive=True)]
  pids = []
  stack = [os.getpid()]
  while stack:
    pid = stack.pop()
    try:
      for tid in os.listdir("/proc/%d/task" % pid):
        with open("/proc/%d/task/%s/children" % (pid, tid)) as fp:
          kids = [int(c) for c in fp.read().split()]
        pids += kids
        stack += kids
    except (OSError, ValueError):
      pass
  return pids

def currentRss(pid):
  try:
    if isWin:
      return psutil.Process(pid).memory_info().rss
    with open("/proc/%d/statm" % pid) as fp:
      return int(fp.read().split()[1]) * pageSize
  except (OSError, ValueError, IndexError, psutil.Error):
    return 0

def peakRss(pid):
  """The most memory a running process has had resident, in bytes."""
  try:
    if isWin:
      return psutil.Process(pid).memory_info().peak_wset
    with open("/proc/%d/status" % pid) as fp:
      for line in fp:
        if line.startswith("VmHWM:"):
          return int(line.split()[1]) * 1024
  except (OSError, ValueError, IndexError, psutil.Error):
    pass
  return 0

# Sampled sum over the tree at one instant, and the kernel's exact peak of the
# largest single process, which covers a spike between two samples.
treePeak = 0
processPeak = 0

preferredVictims = set()

def preferOomKill(pid):
  """Offer a child to the OOM killer ahead of this process, so that omc dies and
  python lives to report the phase it had reached.

  Raising a child is allowed unprivileged; lowering this process is not.
  """
  if isWin or pid in preferredVictims:
    return
  preferredVictims.add(pid)
  try:
    with open("/proc/%d/oom_score_adj" % pid, "w") as fp:
      fp.write("1000")
  except OSError:
    pass

def sampleTree():
  global treePeak
  while True:
    pids = descendants()
    for pid in pids:
      preferOomKill(pid)
    treePeak = max(treePeak, sum(currentRss(pid) for pid in pids))
    time.sleep(0.2)

def noteRss(rss):
  global processPeak
  processPeak = max(processPeak, rss)

def noteChildrenRss():
  """What is still running (omc lives on in a wasm-jit session) and what has
  been waited for (make and its compilers, the simulation executable)."""
  for pid in descendants():
    noteRss(peakRss(pid))
  if resource is not None:
    maxrss = resource.getrusage(resource.RUSAGE_CHILDREN).ru_maxrss
    noteRss(maxrss if sys.platform == "darwin" else maxrss * 1024)

threading.Thread(target=sampleTree, daemon=True).start()

# What a data reconciliation run writes beside the executable, besides the
# files its report links: the reconciled values and the extracted model.
dataReconciliationExtraFiles = ("_Outputs.csv", "_BoundaryConditions_Outputs.csv", "_Reconciled_Sx.csv",
                                "_NonReconcilcedVars.txt", "_BoundaryConditions.html")
hrefRe = re.compile(r'<a\s+href\s*=\s*"?([^"\s>]+)"?', re.I)

def collectDataReconciliation():
  """Copy the report of a data reconciliation run to files/<model>.dr/.

  The runtime writes <model>.html and the pages and logs it links, all next to
  the executable and linked relative to it, so they are copied together into a
  directory of their own and keep working there. The links are read from the
  report rather than listed here, so that whatever the runtime adds comes along.
  """
  prefix = conf["fileName"]
  report = "%s.html" % prefix
  if not os.path.exists(report):
    execstat["dr"] = {"report": False, "reconciled": False}
    return
  files = {report, "Reconciled_%s.mo" % prefix.replace(".", "_")}
  files.update(prefix + suffix for suffix in dataReconciliationExtraFiles)
  pending = [report]
  while pending:
    page = pending.pop()
    with open(page, errors="replace") as fp:
      links = [l for l in hrefRe.findall(fp.read()) if "/" not in l and not l.startswith("#")]
    for l in links:
      if l not in files:
        files.add(l)
        if l.endswith(".html") and os.path.exists(l):
          pending.append(l)
  dest = os.path.normpath("../files/%s.dr" % prefix)
  shutil.rmtree(dest, ignore_errors=True)
  os.mkdir(dest)
  copied = []
  for f in sorted(files):
    if os.path.isfile(f):
      shutil.copy(f, dest)
      copied.append(f)
  # The report's "Errors" link is the output of the executable, which simulate()
  # writes to <model>.log and this script to the .sim file.
  log = "%s.log" % prefix
  if log in files and log not in copied and os.path.isfile(simFile):
    shutil.copy(simFile, os.path.join(dest, log))
    copied.append(log)
  execstat["dr"] = {"report": True, "reconciled": os.path.exists(prefix + "_Outputs.csv"), "files": copied}

def writeResult():
  noteChildrenRss()
  execstat["maxrss"] = max(treePeak, processPeak)
  if conf.get("dataReconciliation"):
    try:
      collectDataReconciliation()
    except Exception as e:
      with open(errFile, 'a+') as fp:
        fp.write("Collecting the data reconciliation report failed: %s\n" % e)
  if runningPhase is not None:
    (stat, key, started) = runningPhase
    target = execstat if stat is None else stat
    # Only if the phase did not get to report its own time.
    if not target.get(key):
      target[key] = monotonic() - started
  with open(statFile, 'w') as fp:
    json.dump(execstat, fp)
    fp.flush()
    os.fsync(fp.fileno())

startJob=monotonic()

def isAlive(pid):
  try:
    return psutil.Process(pid).status() != psutil.STATUS_ZOMBIE
  except psutil.Error:
    return False

def cmdline(pid):
  try:
    return " ".join(psutil.Process(pid).cmdline())[:200]
  except psutil.Error:
    return "?"

def waitGone(pids, seconds):
  """The pids of those still alive after that long."""
  deadline = monotonic() + seconds
  while True:
    pids = [pid for pid in pids if isAlive(pid)]
    if not pids or monotonic() >= deadline:
      return pids
    time.sleep(0.05)

def sessionProcesses(session):
  """OMPython starts omc through a shell: that shell and everything below it."""
  process = getattr(session, "_omc_process", None)
  if process is None:
    return []
  try:
    root = psutil.Process(process.pid)
    return [root.pid] + [p.pid for p in root.children(recursive=True)]
  except psutil.Error:
    return []

def quit_omc(session):
  """quit() the session and do not return until its processes are gone.

  OMPython's __del__ would do this at exit, but Python 3.14 runs no __del__ at
  sys.exit while a daemon thread is alive, and the sampler above always is."""
  if session is None:
    return None
  pids = sessionProcesses(session)
  for pid in pids:
    noteRss(peakRss(pid))
  try:
    session.sendExpression("quit()")
  except Exception:
    pass
  process = getattr(session, "_omc_process", None)
  left = waitGone(pids, 2)
  if left:
    with open(errFile, 'a+') as fp:
      fp.write("omc did not exit on quit(); killing %s\n" % ", ".join("%d %s" % (pid, cmdline(pid)) for pid in left))
    for pid in left:
      try:
        os.kill(pid, shared.SIGKILL)
      except OSError:
        pass
    left = waitGone(left, 5)
    if left:
      with open(errFile, 'a+') as fp:
        fp.write("Still alive after SIGKILL: %s\n" % left)
  try:
    process.poll()
  except Exception:
    pass
  return None

def killStrays():
  """Whatever is still below this process once both sessions are gone."""
  strays = descendants()
  if not strays:
    return
  with open(errFile, 'a+') as fp:
    fp.write("Processes left after quitting omc, killing: %s\n" % ", ".join("%d %s" % (pid, cmdline(pid)) for pid in strays))
  for pid in strays:
    try:
      os.kill(pid, shared.SIGKILL)
    except OSError:
      pass
  waitGone(strays, 5)

def writeResultAndExit(exitStatus, useOsExit=False):
  global omc, omc_new
  writeResult()
  print("Calling exit ...")
  with open(errFile, 'a+') as fp:
    if useOsExit:
      msg = "[Calling os._exit(%s), Time elapsed: %s]\n"
    else:
      msg = "[Calling sys.exit(%s), Time elapsed: %s]\n"
    fp.write(msg % (exitStatus, monotonic()-startJob))
    fp.flush()
  sys.stdout.flush()
  omc = quit_omc(omc)
  omc_new = quit_omc(omc_new)
  killStrays()
  if useOsExit:
    os._exit(exitStatus)
  else:
    sys.exit(exitStatus)

class OmcExited(Exception):
  pass

def guardSession(session, timeout):
  """Give the session a sendExpression that cannot block forever.

  OMPython's receives with no timeout: an omc killed mid-command left the main
  thread in a C-level recv, where not even the SIGTERM handler runs. This one
  notices omc dying within a second and gives up on a silent omc after `timeout`."""
  if not isinstance(session, OMCSessionZMQ):
    return
  socket = session._omc
  process = session._omc_process
  socket.setsockopt(zmq.SNDTIMEO, 5000)
  def sendExpression(command, parsed=True):
    if process.poll() is not None:
      raise OmcExited("OMC exited with status %s before: %s" % (process.returncode, command))
    socket.send_string(str(command))
    if command == "quit()":
      socket.close()
      session._omc = None
      return None
    deadline = monotonic() + timeout
    while not socket.poll(1000):
      if process.poll() is not None:
        raise OmcExited("OMC exited with status %s while running: %s" % (process.returncode, command))
      if monotonic() > deadline:
        raise TimeoutError("%s: no answer from omc in %s seconds" % (command, timeout))
    result = socket.recv_string()
    return OMPython.OMTypedParser.parseString(result) if parsed else result
  session.sendExpression = sendExpression

def killChildren(sig, name):
  """Signal everything this process started, one process at a time: Windows has no
  process group to signal instead."""
  for process in psutil.Process().children(recursive=True):
    noteRss(peakRss(process.pid))
    try:
      os.kill(process.pid, sig)
    except (OSError, psutil.Error):
      with open(errFile, 'a+') as fp:
        fp.write("Could not %s process: %s.\n" % (name, process.pid))

def sendExpressionTimeout(omc, cmd, timeout):
  with open(errFile, 'a+') as fp:
    fp.write("%s [Timeout %s]\n" % (cmd, timeout))
  def target(res):
    try:
      ignore = omc.sendExpression("alarm(%s)" % timeout)
      res[0] = omc.sendExpression(cmd)
      with open(errFile, 'a+') as fp:
        fp.write(omc.sendExpression('OpenModelica.Scripting.getErrorString()', parsed = False))
      elapsed = omc.sendExpression("alarm(0)")
      with open(errFile, 'a+') as fp:
        fp.write("[Timeout remaining time %s]\n" % elapsed)
    except Exception as e:
      res[1] = cmd + " " + str(e)

  res=[None,None]
  # A daemon thread, so that one stuck in a ZMQ receive cannot keep the process
  # alive past the exit below
  thread = threading.Thread(target=target, args=(res,), daemon=True)
  thread.start()
  # Poll instead of a single join: if omc dies (crash, ulimit, ...) waiting out
  # the whole timeout first buys nothing.
  # The deadline outwaits omc's own, which aborts the command and answers.
  deadline = monotonic() + timeout + shared.alarmGrace(timeout) + 5
  while thread.is_alive() and monotonic() < deadline:
    thread.join(1)
    if omc._omc_process.poll() is not None:
      break
  status = omc._omc_process.poll()
  if status is not None:
    with open(errFile, 'a+') as fp:
      fp.write("OMC exited with status %s while running: %s\n" % (status, cmd))
      try:
        with open(os.path.normpath(omc._omc_log_file.name)) as omcLog:
          for line in omcLog:
            fp.write(line)
      except IOError:
        pass
    writeResultAndExit(0, True)

  if thread.is_alive():
    with open(errFile, 'a+') as fp:
      fp.write("Thread is still alive.\n")
      if omc._omc_process.poll() is not None:
        fp.write("OMC died, but the thread is still running? This will end badly. The log-file of omc:\n")
        with open(os.path.normpath(omc._omc_log_file.name)) as omcLog:
          for line in omcLog:
            fp.write(line)
        print("OMC died, but the thread is still running? This will end badly.\n")
    killChildren(signal.SIGINT, "SIGINT")
    thread.join(2)
    if thread.is_alive():
      killChildren(shared.SIGKILL, "SIGKILL")
      with open(errFile, 'a+') as fp:
        fp.write("Aborted the command.\n")
      writeResultAndExit(0, True)
    if res[1] is None:
      res[1] = ""
  if res[1] is not None:
    raise TimeoutError(res[1])
  return res[0]

def checkOutputTimeout(cmd, timeout, conf=None):
  with open(errFile, 'a+') as fp:
    fp.write("%s [Timeout %s]\n" % (cmd, timeout))
  def target(res):
    try:
      env = os.environ.copy()
      # add the environmentSimulation to the environment
      if conf:
        for e in conf["environmentSimulation"]:
          env[e[0]] = e[1]
      res[0] = subprocess.check_output(cmd, shell=True, stderr=subprocess.STDOUT, env = env).decode().strip()
    except subprocess.CalledProcessError as e:
      outputStr = e.output.decode("utf-8","backslashreplace")
      res[1] = cmd + " " + outputStr
    except Exception as e:
      res[1] = cmd + " " + str(e)

  res=[None,None]
  thread = threading.Thread(target=target, args=(res,), daemon=True)
  thread.start()
  thread.join(timeout)

  if thread.is_alive():
    killChildren(signal.SIGINT, "SIGINT")
    thread.join(2)
    if thread.is_alive():
      killChildren(shared.SIGKILL, "SIGKILL")
      thread.join(2)
    if res[1] is None:
      res[1] = ""
  if res[1] is not None:
    raise TimeoutError(res[1])
  return res[0]

execstat = {
  "parsing":None,
  "frontend":None,
  "backend":None,
  "simcode":None,
  "templates":None,
  "build":None,
  "sim":None,
  "simwall":None, # Wall clock; sim is what the tool says it spent
  "simcold":None,
  "diff":None,
  "phase":0,
  "maxrss":0, # bytes resident at once across omc, compilers and executable
  # One entry per runner beyond the first, which reports itself in the keys
  # above; see configs/fmi-simulators.json, wasm-fmu-runners.json, solvers.json.
  "simulators":{}
}
simulators = execstat["simulators"]

with open(config) as fp:
  conf = json.load(fp)

try:
  shutil.rmtree(conf["fileName"])
except OSError:
  pass
os.mkdir(conf["fileName"])
os.chdir(conf["fileName"])

dockerExtraArgs = dockerExtraArgs + ["-w", conf["fileName"]]

errFile=os.path.normpath("../files/%s.err" % conf["fileName"])
simFile=os.path.normpath("../files/%s.sim" % conf["fileName"])
statFile=os.path.normpath("../files/%s.stat.json" % conf["fileName"])
try:
  os.unlink(errFile)
except OSError:
  pass
try:
  os.unlink(simFile)
except OSError:
  pass

def terminateHandler(signum, frame):
  """The outer timeout sends SIGTERM before it SIGKILLs the process group. omc is
  not in that group, so unless it is taken down here it outlives the run, and
  without the result file the model has no row at all."""
  with open(errFile, 'a+') as fp:
    fp.write("[Killed by signal %d after %s]\n" % (signum, monotonic()-startJob))
  writeResult()
  killChildren(shared.SIGKILL, "SIGKILL")
  os._exit(1)

signal.signal(signal.SIGTERM, terminateHandler)

def uncaughtException(exctype, value, tb):
  traceback.print_exception(exctype, value, tb)
  with open(errFile, 'a+') as fp:
    fp.write("Uncaught exception: %s\n" % value)
  writeResultAndExit(1, True)

sys.excepthook = uncaughtException

with open(errFile, 'a+') as fp:
  fp.write("Running: %s\n" % " ".join(sys.argv))

if conf["simCodeTarget"] not in ["Cpp","C","C+Rust","wasm-jit"]:
  with open(errFile, 'a+') as fp:
    fp.write("Unknown simCodeTarget in %s" % conf["simCodeTarget"])
  writeResultAndExit(1)
# wasm-jit builds no makefile and no executable; the model is JIT-compiled inside
# the omc that translated it and simulated there via simulate(resimulateExecutable=)
isWasmJit = conf["simCodeTarget"]=="wasm-jit"
# --nobuildmodel: one simulate() instead of translateModel()+resimulate, so omc
# reports the build/simulation split itself
# --wasmfmu: export the model once as a wasm FMU and simulate that one FMU
# several ways (FMI 3.0 ME, FMI 3.0 CS, its own simulation runtime), so the
# model is translated and compiled once however many runs there are
useWasmFmu = isWasmJit and bool(conf.get("wasmfmurunners")) and not conf.get("fmi")
useSimulate = isWasmJit and conf.get("noBuildModel") and not conf.get("fmi") and not useWasmFmu
# --coldhot: simulate again in the same session, where the module is already
# compiled, and report that run instead
useColdHot = isWasmJit and conf.get("coldHot") and not conf.get("fmi") and not useWasmFmu
if isWasmJit and conf.get("fmi"):
  with open(errFile, 'a+') as fp:
    fp.write("FMI export is not supported for simCodeTarget=wasm-jit")
  writeResultAndExit(0)
if conf["simCodeTarget"]=="Cpp" and not conf["haveCppRuntime"]:
  with open(errFile, 'a+') as fp:
    fp.write("C++ runtime not supported in this installation (HelloWorld failed)")
  writeResultAndExit(0)
if conf.get("fmi"):
  if conf["simCodeTarget"]=="Cpp" and not conf["haveFMICpp"]:
    with open(errFile, 'a+') as fp:
      fp.write("C++ FMI runtime not supported in this installation (HelloWorld failed or did not respect fileNamePrefix)")
    writeResultAndExit(0)
  elif conf["simCodeTarget"]=="C" and not conf["haveFMI"]:
    with open(errFile, 'a+') as fp:
      fp.write("C FMI runtime not supported in this installation (HelloWorld failed or did not respect fileNamePrefix)")
    writeResultAndExit(0)

omhome = conf["omhome"]
os.environ["OPENMODELICAHOME"] = omhome

def createOmcSession():
  return OMCSession(docker=docker, dockerExtraArgs=dockerExtraArgs, timeout=5) if corbaStyle else OMCSessionZMQ(docker=docker, dockerExtraArgs=dockerExtraArgs, timeout=5)
def createOmcSessionNew():
  if ompython_omhome != "":
    os.environ["OPENMODELICAHOME"] = ompython_omhome
    return OMCSessionZMQ()
  else:
    return createOmcSession()
omc = createOmcSession()
omc_new = createOmcSessionNew()
# A backstop only: sendExpressionTimeout enforces the phase deadlines by killing
# omc, which this notices within a second.
for session in (omc, omc_new):
  guardSession(session, 2*(conf["ulimitOmc"]+conf["ulimitExe"]))

cmd = 'setCommandLineOptions("%s")' % conf["omc_thread_cmd"]
if not omc.sendExpression(cmd):
  raise Exception('Could not send %s' % cmd)

try:
  os.unlink(os.path.normpath("%s.tmpfiles" % conf["fileName"]))
except:
  pass
#cmd = 'setCommandLineOptions("--running-testsuite=%s.tmpfiles")' % conf["fileName"]
runningTestsuiteFiles = False
#if omc.sendExpression(cmd):
#  runningTestsuiteFiles = True

# Hide errors for old-school running-testsuite flags...
omc.sendExpression("getErrorString()", parsed = False)

outputFormat="mat"
referenceVars=[]
numberOfIntervalsInReference = 0
referenceFile = conf.get("referenceFile") or ""
if referenceFile != "":
  try:
    compSignals = os.path.normpath(os.path.join(os.path.dirname(referenceFile),"comparisonSignals.txt"))
    if os.path.exists(compSignals):
      referenceVars=[s.strip() for s in open(compSignals).readlines() if (s.strip() != "")] # s.strip().lower() != "time" and ??? I guess we should check time variable...
      print(referenceVars)
    else:
      referenceVars=omc_new.sendExpression('readSimulationResultVars("%s", readParameters=true, openmodelicaStyle=true)' % referenceFile)
    variableFilter=shared.variableFilterOf(referenceVars)
    # get the number of intervals from the file
    numberOfIntervalsInReference = omc_new.sendExpression('readSimulationResultSize("%s")' % referenceFile)
    emit_protected="-emit_protected"
  except:
    referenceFile=""
if referenceFile=="":
  variableFilter=""
  outputFormat="empty"
  emit_protected=""
"""TODO:
compareVarsUri := "modelica://" + /*libraryString*/ "Buildings" + "/Resources/Scripts/OpenModelica/compareVars/#modelName#.mos";
(compareVarsFile,compareVarsFileMessages) := uriToFilename(compareVarsUri);

if regularFileExists(compareVarsFile) then
  runScript(compareVarsFile);
  vars := compareVars;
  variableFilter := sum(stringReplace(stringReplace(s,"[","."),"]",".") + "|" for s in vars) + "time";
  numCompared := size(vars,1);
  emit_protected := " -emit_protected";
"""
# print(variableFilter)

for cmd in conf["customCommands"]:
  omc.sendExpression(str(cmd), parsed = False)

# wasm-jit simulates inside omc, so omc needs the simulation environment.
if isWasmJit:
  for (name, value) in conf["environmentSimulation"]:
    omc.sendExpression('setEnvironmentVar("%s", "%s")' % (name, value.replace("\\","/")), parsed = False)

if conf.get("optlevel"):
  cflags = omc.sendExpression("getCFlags()")
  cflags = cflags.replace("${MODELICAUSERCFLAGS}","").replace("-O0","").replace("-O1","").replace("-O2","").replace("-O3","").strip()
  cflags = re.sub(r"\s*-march=\S+", "", cflags).strip()
  cflags += " " + conf["optlevel"]
  omc.sendExpression(str("setCFlags(\"%s\")" % cflags), parsed = False)

omc.sendExpression('setModelicaPath("%s")' % (libraries+MSLpath,), parsed = False)

if conf.get("ulimitMemory"):
  # Use at most 80% of the vmem for the GC heap; some memory will be used for other purposes than the GC itself
  # Note: Only works on 1.13+ OpenModelica; we still need to ulimit the process for safety
  omc.sendExpression(str("GC_set_max_heap_size(%d);" % (int(conf["ulimitMemory"]*1024*0.8))), parsed = False)

def loadModels(omc, conf):
  for f in conf["loadFiles"]:
    if not sendExpressionTimeout(omc, 'loadFile("%s", uses=false)' % f, conf["ulimitLoadModel"]):
      writeResultAndExit(0)
  loadedFiles = sorted(omc.sendExpression("{getSourceFile(cl) for cl in getClassNames()}"))
  if sorted(conf["loadFiles"]) != loadedFiles:
    print("Loaded the wrong files. Expected:\n%s\nActual:\n%s" % ("\n".join(sorted(conf["loadFiles"])), "\n".join(loadedFiles)))
    sys.exit(1)
newOMLoaded = False
def loadLibraryInNewOM():
  global newOMLoaded
  if not newOMLoaded:
    newOMLoaded = True
    # Broken/old getSimulationOptions; use new one (requires parsing again)
    assert(ompython_omhome!="")
    assert(omc_new.sendExpression('setModelicaPath("%s")' % (libraries+MSLpath,)))
    loadModels(omc_new, conf)

start=monotonic()
try:
  loadModels(omc, conf)
except TimeoutError as e:
  execstat["parsing"]=monotonic()-start
  with open(errFile, 'a+') as fp:
    fp.write("Timeout error for cmd: %s\n%s"%(cmd,str(e)))
  writeResultAndExit(0, True)
execstat["parsing"]=monotonic()-start

try:
  classNames = omc.sendExpression('getClassNames()')
except:
  classNames = []

for cl in classNames:
  try:
    classVersion = omc.sendExpression('getVersion(%s)' % cl)
  except:
    classVersion = "unknown"
  try:
    classSourceFile = omc.sendExpression('getSourceFile(%s)' % cl)
  except:
    classSourceFile = "??? unknown source location"
  with open(errFile, 'a+') as fp:
    fp.write("Using package %s with version %s (%s)\n" % (cl, classVersion, classSourceFile))

def sendExpressionOldOrNew(cmd):
  try:
    return omc.sendExpression(cmd)
  except:
    loadLibraryInNewOM()
    return omc_new.sendExpression(cmd)

haveFlagCheckModel=False
def wasmJitAcceptsFlag(flagVal):
  # There is no HelloWorld executable to probe: the wasm-jit runtime lives in
  # omc, so ask it directly whether a trivial model still simulates.
  global haveFlagCheckModel
  if not haveFlagCheckModel:
    sendExpressionOldOrNew('loadString("model OMLibTestFlagCheck Real x(start = 1, fixed = true); equation der(x) = -x; end OMLibTestFlagCheck;")')
    haveFlagCheckModel=True
  return bool((sendExpressionOldOrNew('simulate(OMLibTestFlagCheck,simflags="%s")' % flagVal) or {}).get("resultFile"))

annotationSimFlags=""
cmd = 'getSimulationOptions(%s,defaultTolerance=%s,defaultNumberOfIntervals=%s)' % (conf["modelName"], conf["defaultTolerance"], max(conf["defaultNumberOfIntervals"], numberOfIntervalsInReference))
try:
  (startTime,stopTime,tolerance,numberOfIntervals,stepSize)=sendExpressionOldOrNew(cmd)
except:
  # omc answers nothing when the call fails, and nothing else reads the buffer.
  raise Exception("%s failed:\n%s" % (cmd, omc.sendExpression("getErrorString()", parsed = False)))
if conf["simCodeTarget"] in ("C","C+Rust","wasm-jit") and sendExpressionOldOrNew('classAnnotationExists(%s, __OpenModelica_simulationFlags)' % conf["modelName"]):
  for flag in sendExpressionOldOrNew('getAnnotationNamedModifiers(%s,"__OpenModelica_simulationFlags")' % conf["modelName"]):
    if flag=="The searched annotation name not found":
      # Old, stupid API
      continue
    val=sendExpressionOldOrNew('getAnnotationModifierValue(%s,"__OpenModelica_simulationFlags","%s")' % (conf["modelName"],flag))
    flagVal=" -noemit -%s=%s" % (flag,val)
    if wasmJitAcceptsFlag("-%s=%s" % (flag,val)) if isWasmJit else shared.simulationAcceptsFlag(flagVal, checkOutput=False, cwd="..", isWin=isWin):
      annotationSimFlags+=" -%s=%s" % (flag,val)
    else:
      with open(errFile, 'a+') as fp:
        fp.write("Ignoring simflag %s since the simulation runtime does not accept it\n" % flagVal)

commandLineOptionsRe = re.compile(r'__OpenModelica_commandLineOptions\s*=\s*\\?"([^"\\]*)')

def modelCommandLineOptions():
  """The flags the model's __OpenModelica_commandLineOptions annotation sets.

  omc applies them itself inside simulate()/buildModelFMU(); the testing needs to
  know about them beforehand to pick how the model can be run at all.
  """
  if not sendExpressionOldOrNew('classAnnotationExists(%s, __OpenModelica_commandLineOptions)' % conf["modelName"]):
    return ""
  opts = []
  for i in range(1, (sendExpressionOldOrNew('getAnnotationCount(%s)' % conf["modelName"]) or 0) + 1):
    text = sendExpressionOldOrNew('getNthAnnotationString(%s, %d)' % (conf["modelName"], i)) or ""
    opts += commandLineOptionsRe.findall(text)
  return " ".join(opts)

# A --daeMode model's Model Exchange interface is a DAE one (fmi-ls-dae): the
# runners that care say how to drive it.
daeMode = useWasmFmu and "--daeMode" in (modelCommandLineOptions() + " " + " ".join(str(c) for c in conf["customCommands"]))

def simulateCmd(resimulate):
  simflags = ("%s %s %s -lv LOG_STATS" % (annotationSimFlags,conf["simFlags"],emit_protected)).strip()
  return 'simulate(%s,startTime=%g,stopTime=%g,tolerance=%g,numberOfIntervals=%d,outputFormat="%s",variableFilter="%s",fileNamePrefix="%s",simflags="%s"%s)' % (conf["modelName"],startTime,stopTime,tolerance,numberOfIntervals,outputFormat,variableFilter,conf["fileName"],simflags,(',resimulateExecutable="%s"' % conf["fileName"]) if resimulate else "")

# TODO: Detect and handle the case where RT_CLOCK is not available in OMC
total_before = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_SIMULATE_TOTAL)")

# The FMU is built once and simulated with every tool the job asked for, so
# that testing FMPy no longer means building the same FMU a second time.  The
# tools are described in configs/fmi-simulators.json.
fmisimulator = conf.get("fmisimulator")
fmisimulators = shared.parseFmiSimulators(conf.get("fmisimulators")) if conf.get("fmi") else []
if conf.get("fmi") and not fmisimulators and fmisimulator:
  fmisimulators = shared.parseFmiSimulators([fmisimulator])

if conf.get("fmi") and any(shared.fmiSimulator(name).get("fmiFlags", {}).get("s") == "cvode" for (name, _) in fmisimulators):
  with open(errFile, 'a+') as fp:
    fp.write("Running command: setCommandLineOptions(\"--fmiFlags=s:cvode\")\n")
  sendExpressionOldOrNew('setCommandLineOptions("--fmiFlags=s:cvode")')

start=monotonic()
timeout = conf["ulimitOmc"]
# If the command has to be killed there is no way to tell which phase it was in,
# so its time is charged to what the command itself is: building an FMU to the
# build, simulating to the simulation, translating to the front end - which is
# also the phase such a model is reported as having failed in.
if conf.get("fmi"):
  cmd='"" <> buildModelFMU(%s,fileNamePrefix="%s",fmuType="%s",version="%s",platforms={"static"})' % (conf["modelName"],conf["fileName"].replace(".","_"),conf["fmuType"],conf["fmi"])
  timedPhase = "build"
elif useWasmFmu:
  # One FMU for every runner, written unzipped: the model kernel alone,
  # which omc links against an adapter it compiled once into its cache. Nothing
  # here is packed, extracted or compiled but the model.
  sendExpressionOldOrNew('setCommandLineOptions("--fmuDirectory=true")')
  cmd='"" <> buildModelFMU(%s,fileNamePrefix="%s",fmuType="me_cs",version="3.0",platforms={"wasm"})' % (conf["modelName"],conf["fileName"].replace(".","_"))
  timedPhase = "build"
elif useSimulate:
  cmd=simulateCmd(resimulate=False)
  timeout = conf["ulimitOmc"] + conf["ulimitExe"]
  timedPhase = "sim"
else:
  # The data reconciliation back end reads the measurements (-sx) from the
  # simulation flags while translating, not only when the executable runs.
  translateSimflags = (',simflags="%s"' % " ".join(f for f in (annotationSimFlags.strip(), conf["simFlags"].strip()) if f)) if conf.get("dataReconciliation") else ""
  cmd='translateModel(%s,tolerance=%g,outputFormat="%s",numberOfIntervals=%d,variableFilter="%s",fileNamePrefix="%s"%s)' % (conf["modelName"],tolerance,outputFormat,numberOfIntervals,variableFilter,conf["fileName"],translateSimflags)
  timedPhase = "frontend"
with open(errFile, 'a+') as fp:
  fp.write("Running command: %s\n"%(cmd))
try:
  phaseStarts(timedPhase)
  res=sendExpressionTimeout(omc, cmd, timeout)
  phaseEnded()
except TimeoutError as e:
  execstat[timedPhase]=monotonic()-start

  with open(errFile, 'a+') as fp:
    fp.write("Timeout error for cmd: %s\n%s"%(cmd,str(e)))
    try:
      with open(os.path.normpath(omc._omc_log_file.name), "r") as fp2:
        fp.write("\n\nOMC output: %s" % fp2.read().strip())
    except (OSError, AttributeError):
      pass

  writeResultAndExit(0)

# See which translateModel phases completed

execTimeTranslateModel=monotonic()-start
simres = None
buildFailed = False
if useSimulate:
  simres = res or {}
  # A failed translate/build is only reported in the messages of the record; the
  # translation clocks below say which of the two it was
  buildFailed = (simres.get("messages") or "").startswith("Failed to build model")
  res = True
err        = omc.sendExpression("OpenModelica.Scripting.getErrorString()")
total      = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_SIMULATE_TOTAL)")-total_before
buildmodel = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_BUILD_MODEL)")
templates  = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_TEMPLATES)")
simcode    = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_SIMCODE)")
backend    = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_BACKEND)")
frontend   = omc.sendExpression("OpenModelica.Scripting.Internal.Time.timerTock(OpenModelica.Scripting.Internal.Time.RT_CLOCK_FRONTEND)")

writeResult()
if not isWasmJit or (useSimulate and not useColdHot):
  # wasm-jit keeps the translated model in this session; it is needed to simulate
  omc = quit_omc(omc)

print(execTimeTranslateModel,frontend,backend)
# The clocks nest, frontend > backend > simcode > templates > buildmodel, each
# reading the time since its own phase started, so a phase's own time is the
# difference to the next one in. -1 is a phase this translation never started.
if backend == -1:
  execstat["phase"]=0
  if frontend != -1:
    execstat["frontend"]=frontend
elif simcode == -1:
  execstat["phase"]=1
  execstat["frontend"]=frontend-backend
  execstat["backend"]=backend
elif templates == -1:
  execstat["phase"]=2
  execstat["frontend"]=frontend-backend
  execstat["backend"]=backend-simcode
  execstat["simcode"]=simcode
else:
  execstat["frontend"]=frontend-backend
  execstat["backend"]=backend-simcode
  execstat["simcode"]=simcode-templates
  # -1: the translation never got to the build, so there is none to take out.
  execstat["templates"]=templates-max(buildmodel, 0.0)
  execstat["phase"]=4 if res else 3

with open(errFile, 'a+') as fp:
  fp.write(err)

if execstat["phase"] < 4:
  writeResultAndExit(0)

start=monotonic()
try:
  if conf.get("fmi") or useWasmFmu:
    if res:
      fmuExpectedLocation = "%s.fmu" % conf["fileName"].replace(".","_")
      execstat["build"] = max(0.0, buildmodel) # Older versions didn't separate translate and build times
      if not os.path.exists(os.path.normpath(fmuExpectedLocation)):
        err += "\n%s was not generated in the expected location: %s" % ("The wasm FMU" if useWasmFmu else "FMU", fmuExpectedLocation)
        execstat["phase"]=4
        writeResultAndExit(0)
      execstat["phase"] = 5
  elif isWasmJit:
    # Nothing to build; simulate() reports the JIT compile as timeCompile, while
    # a resimulate leaves it in the simulation time
    execstat["build"] = simres["timeCompile"] if useSimulate else 0.0
    execstat["phase"] = 5
    if buildFailed:
      with open(errFile, 'a+') as fp:
        fp.write(simres.get("messages") or "")
      writeResultAndExit(0)
  else:
    if isWin:
      res = checkOutputTimeout("\"%s\\share\\omc\\scripts\\Compile.bat\" %s gcc %s parallel dynamic 24 0" % (conf["omhome"], conf["fileName"], msysEnvironment), conf["ulimitOmc"], conf)
    else:
      res = checkOutputTimeout("make -j%s -f %s.makefile" % (conf["procCCompile"], conf["fileName"]), conf["ulimitOmc"], conf)

    execstat["build"] = monotonic()-start
    execstat["phase"] = 5
except TimeoutError as e:
  execstat["build"] = monotonic()-start
  with open(errFile, 'a+') as fp:
    fp.write(str(e))
  writeResultAndExit(0, True)

writeResult()
# Do the simulation

wasmfmurunners = shared.parseWasmFmuRunners(conf.get("wasmfmurunners")) if useWasmFmu else []
# The model is built once and its executable run once per solver; the solvers are
# described in configs/solvers.json.
solverRunners = shared.parseSolvers(conf.get("solvers")) if not conf.get("fmi") and not isWasmJit else []
if daeMode:
  wasmfmurunners = [(name, shared.wasmFmuRunner(name).get("daeModeSimflags") or flags) for (name, flags) in wasmfmurunners]
# One build, several runs: an FMU simulated by several tools, a wasm FMU run
# several ways and a model run by several solvers fan out the same way.
runners = fmisimulators or wasmfmurunners or solverRunners

def fmuWithFlags(name):
  """The FMU a simulator runs: the one built, or a copy whose flags file holds
  the fmiFlags of its entry, from which the C runtime picks its CS solver."""
  prefix = conf["fileName"].replace(".","_")
  fmu = "%s.fmu" % prefix
  flags = shared.fmiSimulator(name).get("fmiFlags")
  if not flags:
    return fmu
  copy = "%s_%s.fmu" % (prefix, name)
  flagsFile = "resources/%s_flags.json" % prefix
  with zipfile.ZipFile(fmu) as src, zipfile.ZipFile(copy, "w") as dst:
    for item in src.infolist():
      if item.filename != flagsFile:
        dst.writestr(item, src.read(item))
    dst.writestr(flagsFile, "{\n%s\n}\n" % ",\n".join('  "%s" : "%s"' % kv for kv in flags.items()), zipfile.ZIP_DEFLATED)
  return copy

fmus = dict((name, fmuWithFlags(name)) for (name, _) in fmisimulators)

def runnerSuffix(name):
  """What tells the files of one runner from those of another. The first one
  publishes the workspace itself, so its files keep the plain names."""
  return "_%s" % name if name and runners and name != runners[0][0] else ""

def runnerDir(name):
  """A working directory of this runner's own, or None when there is only one.

  A file the model writes on its first run and reads back on the next --
  Buildings' ground temperature-response matrix under `tmp/`, an EnergyPlus
  scratch directory -- is otherwise computed by whichever runner goes first and
  found already cached by the rest, which reads as the later ones being faster.
  The build stays in the directory above and every runner reaches it as `..`, so
  the result files stay where the report expects them.
  """
  if len(runners) < 2 or not name:
    return None
  d = "run_%s" % name
  if not os.path.isdir(d):
    os.mkdir(d)
  return d

def fromRunnerDir(runDir, path):
  """`path`, which names something in the build directory, as a runner sees it."""
  return path if not runDir or os.path.isabs(path) else "../%s" % path

def inRunnerDir(runDir, cmd):
  """`cmd` run in the runner's directory. The pipe and the log stay outside it."""
  return "(cd %s && %s)" % (runDir, cmd) if runDir else cmd

def resultFile(name=None):
  """Where a simulator writes its results."""
  # Only an FMI tool decides the format; the others write what the model was
  # translated for.
  extension = shared.fmiSimulator(name)["resultExtension"] if (name and fmisimulators) else outputFormat
  return "%s%s_res.%s" % (conf["fileName"], runnerSuffix(name), extension)

def artifactPrefix(name=None):
  """The files a simulator's results are written to, under files/."""
  return os.path.abspath("../files/%s%s" % (conf["fileName"], runnerSuffix(name))).replace('\\','/')

resFile = resultFile(runners[0][0]) if runners else resultFile()

# The variables an FMI tool has to record. sh -c takes a command of at most
# 128 KiB, so a longer list is left out and the tool records its outputs.
fmiOutputVariables = " ".join(shlex.quote(v) for v in referenceVars if v != "time")
if len(fmiOutputVariables) > 100000:
  fmiOutputVariables = ""

def simulateFmu(name, command, resFile, simFile):
  """Run the FMU with one simulator, writing what it says to simFile."""
  suffix = runnerSuffix(name)
  runDir = runnerDir(name)
  fmitmpdir = "temp_%s%s_fmu" % (conf["fileName"].replace(".","_"), suffix)
  with open("%s.tmpfiles" % conf["fileName"], "a+") as fp:
    fp.write("%s\n" % (os.path.join(runDir, fmitmpdir) if runDir else fmitmpdir))
  cmd = shared.fmiSimulatorCommand(name, command,
                                   fmu=fromRunnerDir(runDir, fmus[name]),
                                   interface=shared.fmiSimulator(name).get("interface", "") if conf["fmuType"] == "me_cs" else "",
                                   result=fromRunnerDir(runDir, resFile),
                                   requestedResult=fromRunnerDir(runDir, resFile) if outputFormat != "empty" else "",
                                   tempDir=fmitmpdir, startTime=startTime, stopTime=stopTime,
                                   tolerance=tolerance, timeout=conf["ulimitExe"],
                                   # OMSimulator refuses a step size of 0; with stopTime=startTime there is no step.
                                   stepSize=stepSize if stopTime > startTime else 1.0,
                                   outputVariables=fmiOutputVariables)
  cmd = inRunnerDir(runDir, cmd)
  with open(simFile,"w") as fp:
    fp.write("%s\n" % cmd)
  pipe = "%s%s" % (conf["fileName"], suffix)
  return checkOutputTimeout("(rm -f %s.pipe ; mkfifo %s.pipe ; head -c 1048576 < %s.pipe >> %s & %s > %s.pipe 2>&1)"
                            % (pipe,pipe,pipe,simFile,cmd,pipe), 1.05*conf["ulimitExe"], conf)

def wasmFmuCmd(runnerFlags, resFile, runDir):
  """The simulate() that runs the exported FMU one way.

  Nothing is translated: `resimulateExecutable` points at the FMU, `-s
  fmi3:...` picks which of its interfaces runs, and the experiment comes from
  the flags rather than from what the export baked in.
  """
  # An empty output format is a run with nothing to compare against, so it is
  # asked for no result file at all rather than one nobody reads.
  resultArgument = "-noemit" if outputFormat == "empty" else "-r=%s" % fromRunnerDir(runDir, resFile)
  # The export baked in no filter, and the variableFilter argument below only
  # reaches a model through the build this run skips.
  filterArgument = "" if variableFilter in ("", ".*") else "-variableFilter=%s" % variableFilter
  simflags = " ".join(x for x in (annotationSimFlags, conf["simFlags"], emit_protected,
                                  "-lv LOG_STATS",
                                  "-startTime=%g -stopTime=%g -tolerance=%g -stepSize=%g" % (startTime,stopTime,tolerance,stepSize),
                                  filterArgument, resultArgument, runnerFlags) if x.strip())
  return 'simulate(%s,startTime=%g,stopTime=%g,tolerance=%g,numberOfIntervals=%d,outputFormat="%s",variableFilter="%s",fileNamePrefix="%s",simflags="%s",resimulateExecutable="%s")' % (
      conf["modelName"],startTime,stopTime,tolerance,numberOfIntervals,outputFormat,variableFilter,conf["fileName"],simflags,fromRunnerDir(runDir, "%s.fmu" % conf["fileName"].replace(".","_")))

def simulateWasmFmu(name, runnerFlags, resFile, simFile):
  """Run the FMU one way, writing what omc says to simFile.

  Returns what simulate() answered; an empty resultFile is a failed run.
  """
  runDir = runnerDir(name)
  cmd = wasmFmuCmd(runnerFlags, resFile, runDir)
  # The export is a directory, and a zipped one unpacks itself beside the .fmu on
  # the first run; the cleanup removes what this file names.
  with open("%s.tmpfiles" % conf["fileName"], "a+") as fp:
    fp.write("%s.fmu\n%s_artifact\n" % (conf["fileName"].replace(".","_"), conf["fileName"].replace(".","_")))
  with open(simFile, "w") as fp:
    fp.write("startTime=%g\nstopTime=%g\ntolerance=%g\nnumberOfIntervals=%d\nstepSize=%g\n" % (startTime,stopTime,tolerance,numberOfIntervals,stepSize))
    fp.write("wasm FMU (%s: %s): %s\n" % (name, shared.wasmFmuRunner(name).get("description") or "", cmd))
  try:
    if runDir:
      sendExpressionTimeout(omc, 'cd("%s")' % runDir, conf["ulimitOmc"])
    res = sendExpressionTimeout(omc, cmd, conf["ulimitExe"]) or {}
  finally:
    # A run that timed out took omc with it; there is then nothing to change back.
    if runDir:
      try:
        sendExpressionTimeout(omc, 'cd("..")', conf["ulimitOmc"])
      except Exception:
        pass
  with open(simFile, "a+") as fp:
    fp.write(res.get("messages") or "")
  return res

def simulateExecutable(name, solverFlags, resFile, simFile):
  """Run the built executable once, with the flags of one solver."""
  runDir = runnerDir(name)
  exeName = "%s.bat" % conf["fileName"] if isWin else conf["fileName"]
  exe = fromRunnerDir(runDir, exeName) if runDir else (".\\%s" % exeName if isWin else "./%s" % exeName)
  # A run sharing the directory with other solvers needs a result file of its own.
  # A run in a directory of its own needs one named explicitly either way: the
  # default lands beside the executable, which is no longer the working directory.
  resultArgument = "-r=%s" % fromRunnerDir(runDir, resFile) if (runDir or runnerSuffix(name)) and outputFormat != "empty" else ""
  # `-inputPath` because the setup XML, the info JSON and the serialized
  # sparsity patterns are all read from the build directory, not from here.
  setupArgument = "-inputPath=.." if runDir else ""
  cmd = inRunnerDir(runDir, " ".join(x for x in (exe, annotationSimFlags, conf["simFlags"], emit_protected,
                             "-lv LOG_STATS" if conf["simCodeTarget"] in ("C","C+Rust") else "",
                             setupArgument, resultArgument, solverFlags) if x.strip()))
  with open(simFile,"w") as fp:
    fp.write("Environment - simulationEnvironment:\n")
    for e in conf["environmentSimulation"]:
      fp.write("%s = %s\n" % (e[0], e[1]))
    fp.write("startTime=%g\nstopTime=%g\ntolerance=%g\nnumberOfIntervals=%d\nstepSize=%g\n" % (startTime,stopTime,tolerance,numberOfIntervals,stepSize))
    if name:
      fp.write("Regular simulation (%s: %s): %s\n" % (name, shared.solver(name).get("description") or "", cmd))
    else:
      fp.write("Regular simulation: %s\n" % cmd)
  if isWin:
    return checkOutputTimeout("%s >> %s" % (cmd,simFile), conf["ulimitExe"], conf)
  pipe = "%s%s" % (conf["fileName"], runnerSuffix(name))
  return checkOutputTimeout("(rm -f %s.pipe ; mkfifo %s.pipe ; head -c 1048576 < %s.pipe >> %s & %s > %s.pipe 2>&1)" % (pipe,pipe,pipe,simFile,cmd,pipe), conf["ulimitExe"], conf)

def simElapsed():
  # omc's own time: the wall clock here covers the wrong run for these flags.
  # A run omc aborted reports none, and then the wall clock is all there is.
  if useSimulate or useColdHot or useWasmFmu:
    return (simres or {}).get("timeSimulation") or (monotonic()-start)
  return monotonic()-start

start=monotonic()
# Set when the first FMI simulator fails and there are others waiting for the
# same FMU, so that its result file is not compared against the reference.
firstSimulatorFailed = False
# omc dying on its own alarm ends the run from inside sendExpressionTimeout, so
# the handler below never runs; naming the phase covers that way out too.
phaseStarts("sim")
try:
  # TODO: Timeout more reliably...
  if conf.get("fmi"):
    if not fmisimulators:
      with open(simFile,"w") as fp:
        fp.write("No FMI simulator available\n")
      writeResultAndExit(0)
    (name, command) = fmisimulators[0]
    res = simulateFmu(name, command, resFile, simFile)
  elif useWasmFmu:
    (name, runnerFlags) = wasmfmurunners[0]
    simres = simulateWasmFmu(name, runnerFlags, resFile, simFile)
    if not simres.get("resultFile"):
      # The same shape a failing FMI simulator takes: the handler below decides
      # whether the other runners of this FMU still get their turn.
      raise TimeoutError("%s failed to simulate the wasm FMU" % name)
  elif isWasmJit:
    if not useSimulate:
      cmd = simulateCmd(resimulate=True)
    with open(simFile,"w") as fp:
      fp.write("startTime=%g\nstopTime=%g\ntolerance=%g\nnumberOfIntervals=%d\nstepSize=%g\n" % (startTime,stopTime,tolerance,numberOfIntervals,stepSize))
      fp.write("wasm-jit simulation: %s\n" % cmd)
    if not useSimulate:
      simres = sendExpressionTimeout(omc, cmd, conf["ulimitExe"]) or {}
    with open(simFile,"a+") as fp:
      fp.write(simres.get("messages") or "")
    if not simres.get("resultFile"):
      execstat["sim"] = simElapsed()
      writeResultAndExit(0)
    if useColdHot:
      execstat["simcold"] = simElapsed()
      cmd = simulateCmd(resimulate=True)
      with open(simFile,"a+") as fp:
        fp.write("wasm-jit hot simulation: %s\n" % cmd)
      hotres = sendExpressionTimeout(omc, cmd, conf["ulimitExe"]) or {}
      with open(simFile,"a+") as fp:
        fp.write(hotres.get("messages") or "")
      if hotres.get("resultFile"):
        simres = hotres
      else:
        with open(errFile, 'a+') as fp:
          fp.write("The hot simulation failed; keeping the cold time\n")
  else:
    executable = os.path.normpath("%s.bat" % conf["fileName"] if isWin else conf["fileName"])
    if not os.path.exists(executable):
      with open(errFile, 'a+') as fp:
        fp.write("The simulation executable %s does not exist\n" % executable)
      execstat["sim"] = monotonic()-start
      writeResultAndExit(0)
    (name, solverFlags) = solverRunners[0] if solverRunners else (None, "")
    res = simulateExecutable(name, solverFlags, resFile, simFile)
  execstat["sim"] = simElapsed()
  execstat["simwall"] = monotonic()-start
  execstat["phase"] = 6
  phaseEnded()
except TimeoutError as e:
  execstat["sim"] = monotonic()-start
  execstat["simwall"] = execstat["sim"]
  phaseEnded()
  # checkOutputTimeout raises TimeoutError for a command that fails as well as
  # for one that runs out of time, so this covers both.
  if len(runners) > 1:
    # The build is done and the other runners are about to use it. What the
    # first one did says nothing about them, so record the failure and let them
    # have their turn. Ending the model here would write them all down as having
    # failed at this phase without ever being started, which is what the loop
    # below already avoids for a failure in any simulator but the first.
    firstSimulatorFailed = True
    with open(errFile, 'a+') as fp:
      fp.write("%s failed or timed out simulating it; the others still get to run it\n"
               % runners[0][0])
  else:
    writeResultAndExit(0, True)

def verifyAgainstReference(resFile, prefix, stat):
  """Compare one simulation result against the reference file.

  Fills stat["diff"] and stat["phase"] exactly as the single simulator code
  did, but returns instead of ending the run, so that the other simulators
  of the same FMU can be verified too.
  """
  if referenceFile=="":
    return
  if len(referenceVars)==0:
    stat["diff"] = {"time":0.0, "vars":[], "numCompared":0}
    stat["phase"]=7
    return


  if not os.path.exists(os.path.normpath(resFile)):
    with open(errFile, 'a+') as fp:
      fp.write("TODO: How the !@#!# did the simulation report success but simulation result %s does not exist to compare? outputFormat=%s" % (resFile,outputFormat))
    return

  start=monotonic()
  if False and conf["simCodeTarget"] in ["Cpp"]: # This is a work-around for older C++ runtime not supporting variable filters. We don't really need it for master, so let's no use it.
    if not sendExpressionTimeout(omc_new, 'filterSimulationResults("%s", "updated%s", vars={%s}, removeDescription=false, hintReadAllVars=false)' % (resFile, resFile, ", ".join(['"%s"' % s for s in referenceVars])), conf["ulimitOmc"]):
      with open(errFile, 'a+') as fp:
        fp.write("Failed to filter simulation results. Took time: %.2f\n" % (monotonic()-start))
      return
    os.remove(resFile)
    os.rename("updated" + resFile, resFile)
    with open(errFile, 'a+') as fp:
      fp.write("Filtered simulation results in time: %.2f\n" % (monotonic()-start))
  start=monotonic()
  try:
    # An empty diffPrefix: no per-variable CSV, the two filtered files below are the report.
    (referenceOK,diffVars) = sendExpressionTimeout(omc_new, 'diffSimulationResults("%s","%s","",relTol=%g,relTolDiffMinMax=%g,rangeDelta=%g)' %
                               (resFile, referenceFile, conf["reference_reltol"],conf["reference_reltolDiffMinMax"], conf["reference_rangeDelta"]), conf["ulimitOmc"])
  except TimeoutError as e:
    with open(errFile, 'a+') as fp:
      fp.write("Timeout error for diffSimulationResults")
    return

  stat["diff"] = {"time":monotonic()-start, "vars":[], "numCompared":len(referenceVars)}
  if len(diffVars)==0 and referenceOK:
    stat["phase"]=7
    with open(errFile, 'a+') as fp:
      fp.write("Reference file matches\n")
  else:
    with open(errFile, 'a+') as fp:
      fp.write(omc_new.sendExpression('OpenModelica.Scripting.getErrorString()', parsed = False))
      fp.write("\nVariables in the reference:" )
      fp.write(",".join(referenceVars)+"\n")
      resVars=omc_new.sendExpression('readSimulationResultVars("%s", readParameters=true, openmodelicaStyle=true)' % resFile)
      fp.write("\nVariables in the result:" )
      fp.write(",".join(resVars)+"\n")
    stat["diff"]["vars"]=diffVars
    # Both files reduced to the differing variables: what the report's OMPlot
    # link compares, instead of a CSV and an HTML page per variable.
    filterDiffVars(resFile, prefix + ".mat", diffVars)
    filterDiffVars(referenceFile, prefix + ".ref.mat", diffVars)

def filterDiffVars(inFile, outFile, diffVars):
  vars = ", ".join('"%s"' % v.replace('\\', '\\\\').replace('"', '\\"') for v in diffVars)
  try:
    ok = sendExpressionTimeout(omc_new, 'filterSimulationResults("%s", "%s", vars={%s}, removeDescription=false)' % (inFile, outFile, vars), conf["ulimitOmc"])
  except TimeoutError as e:
    ok = False
  if not ok:
    with open(errFile, 'a+') as fp:
      fp.write("Failed to write the differing variables of %s to %s:\n%s" % (inFile, outFile, omc_new.sendExpression('OpenModelica.Scripting.getErrorString()', parsed = False)))
    if os.path.exists(outFile):
      os.remove(outFile)

# The first simulator's results are the ones every non-FMI code path expects.
# There is nothing to compare when it never produced any.
if not firstSimulatorFailed:
  verifyAgainstReference(resFile, artifactPrefix(runners[0][0] if runners else None) + ".diff", execstat)

# The build is done; every other runner the job asked for is now only a
# simulation and a comparison. One that times out or fails takes its own
# results down with it and leaves the others alone - the first one included,
# see the TimeoutError handler above.
for (name, command) in runners[1:]:
  stat = {"sim": None, "simwall": None, "diff": None, "phase": 5}
  simulators[name] = stat
  simFileOther = os.path.abspath("../files/%s_%s.sim" % (conf["fileName"], name)).replace('\\','/')
  other = resultFile(name)
  start = monotonic()
  phaseStarts("sim", stat)
  try:
    if useWasmFmu:
      res = simulateWasmFmu(name, command, other, simFileOther)
      stat["sim"] = res.get("timeSimulation") or (monotonic()-start)
      stat["simwall"] = monotonic()-start
      if not res.get("resultFile"):
        writeResult()
        continue
    else:
      if solverRunners:
        simulateExecutable(name, command, other, simFileOther)
      else:
        simulateFmu(name, command, other, simFileOther)
      stat["sim"] = monotonic()-start
      stat["simwall"] = stat["sim"]
    stat["phase"] = 6
    verifyAgainstReference(other, artifactPrefix(name) + ".diff", stat)
  except TimeoutError as e:
    stat["sim"] = monotonic()-start
    stat["simwall"] = stat["sim"]
    with open(errFile, 'a+') as fp:
      fp.write("%s timed out simulating the %s\n" % (name, "model" if solverRunners else "FMU"))
  phaseEnded()
  writeResult()

# quit omc_new: every verification needed it
omc_new = quit_omc(omc_new)

writeResultAndExit(0)