Herwig6Instance.cc

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#include <iostream>
#include <sstream>
#include <cstdlib>
#include <cstring>
#include <cctype>
#include <string>

#ifdef _POSIX_C_SOURCE
#   include <sys/time.h>
#   include <signal.h>
#   include <setjmp.h>
#endif

#include <CLHEP/Random/RandomEngine.h>

#include <HepMC/HerwigWrapper6_4.h>

#include "FWCore/Utilities/interface/Exception.h"
#include "FWCore/MessageLogger/interface/MessageLogger.h"

#include "GeneratorInterface/Core/interface/RNDMEngineAccess.h"

#include "GeneratorInterface/Herwig6Interface/interface/herwig.h"
#include "GeneratorInterface/Herwig6Interface/interface/Herwig6Instance.h"

#include "params.inc"

using namespace gen;

// implementation for the Fortran callbacks from Herwig

// this gets a random number from the currently running instance
// so, if the have separate instances for let's say decayers based on
// Herwig than the Herwig pp collision instance, we get independent
// random numbers.  Also true for FastSim, since FastSim uses its own
// random numbers.  This means FastSim needs take a Herwig6Instance
// instance of its own instead of calling into Herwig directly.
double gen::hwrgen_(int *idummy)
{ return FortranInstance::getInstance<Herwig6Instance>()->randomEngine->flat(); }

void gen::cms_hwwarn_(char fn[6], int *code, int *exit)
{
    std::string function(fn, fn + sizeof fn);
    *exit = FortranInstance::getInstance<Herwig6Instance>()->hwwarn(function, *code);
}

extern "C" {
    void hwaend_()
    {}

    void cmsending_(int *ecode)
    {
        throw cms::Exception("Herwig6Error")
            << "Herwig6 stopped run with error code " << *ecode
            << "." << std::endl;
    }
}

// Herwig6Instance methods

Herwig6Instance::Herwig6Instance(CLHEP::HepRandomEngine *randomEngine) :
    randomEngine(randomEngine ? randomEngine : &getEngineReference()),
    timeoutPrivate(0)
{
}

Herwig6Instance::Herwig6Instance(int dummy) :
    randomEngine(0),
    timeoutPrivate(0)
{
}

Herwig6Instance::~Herwig6Instance()
{
}

// timeout tool

#ifdef _POSIX_C_SOURCE
// some deep POSIX hackery to catch HERWIG sometimes (O(10k events) with
// complicated topologies) getting caught in and endless loop :-(

void Herwig6Instance::_timeout_sighandler(int signr)
{ siglongjmp(*(sigjmp_buf*)FortranInstance::getInstance<Herwig6Instance>()->timeoutPrivate, 1); }

bool Herwig6Instance::timeout(unsigned int secs, void (*fn)())
{
    if (timeoutPrivate)
        throw cms::Exception("ReentrancyProblem")
            << "Herwig6Instance::timeout() called recursively."
            << std::endl;
    struct sigaction saOld;
    std::memset(&saOld, 0, sizeof saOld);

    struct itimerval itv;
    timerclear(&itv.it_value);
    timerclear(&itv.it_interval);
    itv.it_value.tv_sec = 0;
    itv.it_interval.tv_sec = 0;
    setitimer(ITIMER_VIRTUAL, &itv, NULL);

    sigset_t ss;
    sigemptyset(&ss);
    sigaddset(&ss, SIGVTALRM);

    sigprocmask(SIG_UNBLOCK, &ss, NULL);
    sigprocmask(SIG_BLOCK, &ss, NULL);

    timeoutPrivate = new sigjmp_buf;
    if (sigsetjmp(*(sigjmp_buf*)timeoutPrivate, 1)) {
        delete (sigjmp_buf*)timeoutPrivate;
        timeoutPrivate = 0;

        itv.it_value.tv_sec = 0;
        itv.it_interval.tv_sec = 0;
        setitimer(ITIMER_VIRTUAL, &itv, NULL);
        sigprocmask(SIG_UNBLOCK, &ss, NULL);
        return true;
    }

    itv.it_value.tv_sec = secs;
    itv.it_interval.tv_sec = secs;
    setitimer(ITIMER_VIRTUAL, &itv, NULL);

    struct sigaction sa;
    std::memset(&sa, 0, sizeof sa);
    sa.sa_handler = &Herwig6Instance::_timeout_sighandler;
    sa.sa_flags = SA_ONESHOT;
    sigemptyset(&sa.sa_mask);

    sigaction(SIGVTALRM, &sa, &saOld);
    sigprocmask(SIG_UNBLOCK, &ss, NULL);

    try {
        fn();
    } catch(...) {
        delete (sigjmp_buf*)timeoutPrivate;
        timeoutPrivate = 0;

        itv.it_value.tv_sec = 0;
        itv.it_interval.tv_sec = 0;
        setitimer(ITIMER_VIRTUAL, &itv, NULL);

        sigaction(SIGVTALRM, &saOld, NULL);

        throw;
    }

    delete (sigjmp_buf*)timeoutPrivate;
    timeoutPrivate = 0;

    itv.it_value.tv_sec = 0;
    itv.it_interval.tv_sec = 0;
    setitimer(ITIMER_VIRTUAL, &itv, NULL);

    sigaction(SIGVTALRM, &saOld, NULL);

    return false;
}
#else
bool Herwig6Instance::timeout(unsigned int secs, void (*fn)())
{
    fn();
    return false;
}
#endif

bool Herwig6Instance::hwwarn(const std::string &fn, int code)
{
    return false;
}

// regular Herwig6Instance methods

bool Herwig6Instance::give(const std::string &line)
{   
    typedef std::istringstream::traits_type traits;

    const char *p = line.c_str(), *q;
    p += std::strspn(p, " \t\r\n");

    for(q = p; std::isalnum(*q); q++);
    std::string name(p, q - p);

    const ConfigParam *param;
    for(param = configParams; param->name; param++)
        if (name == param->name)
            break;
    if (!param->name)
        return false;

    p = q + std::strspn(q, " \t\r\n");  

    std::size_t pos = 0;
    std::size_t mult = 1;
    for(unsigned int i = 0; i < 3; i++) {
        if (!param->dim[i].size)
            break;

        if (*p++ != (i ? ',' : '('))
            return false;

        p += std::strspn(p, " \t\r\n");

        for(q = p; std::isdigit(*q); q++);
        std::istringstream ss(std::string(p, q - p));
        std::size_t index;
        ss >> index;
        if (ss.bad() || ss.peek() != traits::eof())
            return false;

        if (index < param->dim[i].offset)
            return false;
        index -= param->dim[i].offset;
        if (index >= param->dim[i].size)
            return false;

        p = q + std::strspn(q, " \t\r\n");

        pos += mult * index;
        mult *= param->dim[i].size;
    }

    if (param->dim[0].size) {
        if (*p++ != ')')
            return false;
        p += std::strspn(p, " \t\r\n");
    }

    if (*p++ != '=')
        return false;
    p += std::strspn(p, " \t\r\n");

    for(q = p; *q && (std::isalnum(*q) || std::strchr(".-+", *q)); q++);
    std::istringstream ss(std::string(p, q - p));

    p = q + std::strspn(q, " \t\r\n");
    if (*p && *p != '!')
        return false;

    switch(param->type) {
        case kInt: {
        int value;
        ss >> value;
        if (ss.bad() || ss.peek() != traits::eof())
            return false;

        ((int*)param->ptr)[pos] = value;
        break;
        }
        case kDouble: {
        double value;
        ss >> value;
        if (ss.bad() || ss.peek() != traits::eof())
            return false;

        ((double*)param->ptr)[pos] = value;
        break;
        }
        case kLogical: {
        std::string value_;
        ss >> value_;
        if (ss.bad() || ss.peek() != traits::eof())
            return false;

        for(std::string::iterator iter = value_.begin();
            iter != value_.end(); ++iter)
            *iter = std::tolower(*iter);
        bool value;
        if (value_ == "yes" || value_ == "true" || value_ == "1")
            value = true;
        else if (value_ == "no" || value_ == "false" || value_ == "0")
            value = false;
        else
            return false;

        ((int*)param->ptr)[pos] = value;
        break;
        }
    }

    return true;
}