drive program

jruby は pid をなかなか正しく返してくれない... $$ も Process.pid も, 1.1rc2 でもだ。

java の API には pid をえる標準的なものは見当たらない。

Groovy はプロセスに相当するようなものを別に持っているとは思えない。

jython もすこし頭をよぎったが、動かすことが先決、ということで C++ だ。

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#include 
using namespace std;
class tcfg {

public:

  string java;

  string opts;

  string cls;
  tcfg(string j, string o, string c) : java(j), opts(o), cls(c) { }

};
#define JAVA_PATH "/usr/java/bin/java"
tcfg tcfgs[] = {

  tcfg(JAVA_PATH, "-XX:+PrintClassHistogram -XX:+UseSerialGC", "Test"),

  tcfg(JAVA_PATH, "-XX:+PrintClassHistogram -XX:+UseConcMarkSweepGC", "Test"),

  tcfg(JAVA_PATH, "-XX:+PrintClassHistogram -XX:+UseParallelGC", "Test"),

};
string memopts = "-Xmx24m -XX:MaxPermSize=4m -XX:ReservedCodeCacheSize=8m";
static vector split(const string &st, const string& sep) {

    // record separator position

    vector sp;

    sp.push_back(0);

    string::size_type pos;

    int index = 0, st_len = st.length();

    int sep_len = sep.length();
    while ((pos = st.find(sep, index)) != string::npos) {

      index = pos + sep_len;

      sp.push_back(index);

      if (index >= st_len) break;

    }
    vector sl;

    for (int i = 0; i < sp.size(); i++) {

      if ((i+1) == sp.size()) { // special case for last index

        sl.push_back(st.substr(sp[i], st.length()-sp[i]));

        continue; // can be break

      }

      sl.push_back(st.substr(sp[i], sp[i+1]-sp[i]-sep_len));

    }
    return sl;

}
void doit(tcfg& cfg) {

  pid_t cpid = fork();
 if (cpid == 0) {

   vector mopts = split(memopts, " "); //2

   vector opts = split(cfg.opts, " "); //3

   char **args = new char*[mopts.size() + opts.size() + 3];  // 8
   //args[0] = "java";

   args[0] = const_cast(cfg.java.c_str());
   int off = 1;  // 1

   for (int i = 0; i < mopts.size(); i++) {

     args[i+off] = const_cast(mopts[i].c_str());

   }

   off += mopts.size(); // 3

   for (int i = 0; i < opts.size(); i++) {

     args[i+off] = const_cast(opts[i].c_str());

   }

   off += opts.size(); // 6

   args[off] = const_cast(cfg.cls.c_str());

   off += 1;

   args[off] = 0;
   cout << "a: ";

   for (int i = 0; i <= off; i++) {

     cout << args[i] << " ";

   }

   cout << endl;
   pid_t pid = getpid();

   stringstream ss;

   ss << "out." << dec << pid;

   string ofn = ss.str();
   stringstream sse;

   sse << "err." << dec << pid;

   string efn = sse.str();
   close(1);

   open(ofn.c_str(), O_RDWR|O_CREAT, 0644);

   close(2);

   open(efn.c_str(), O_RDWR|O_CREAT, 0644);
   int r = execv(cfg.java.c_str(), args);
   if (r) {

     cout << "exec error: " << strerror(errno) << endl;

   }
 } else if (cpid > 0) {

   cout << "child pid " << dec << cpid << endl;

   sleep(10);

   cout << "parent sending signal 3" << endl;

   int r = kill(cpid, SIGQUIT);

   sleep(5);
   cout << "parent sending signal 2" << endl;

   r = kill(cpid, SIGINT);

   cout << "parent sending signal 15" << endl;

   r = kill(cpid, SIGTERM);
   int wstat;

   pid_t wr = waitpid(cpid, &wstat, 0);
   cout << "wait returned for " << wr << endl;
   struct stat statbuf;
   r = stat("core", &statbuf);
   if (r == 0) {

     stringstream ss;

     ss << "core." << dec << cpid;

     string cfn = ss.str();

     r = rename("core", cfn.c_str());

     cout << "core found.  renamed to " << cfn << endl;

   }

 } else {

   cout << "fork error: " << strerror(errno) << endl;

 }

}
void setupSig()

{

  struct sigaction act;
  memset(&act, 0, sizeof(act));
  act.sa_handler = SIG_IGN;

  act.sa_flags = SA_NOCLDWAIT;

  int r = sigaction(SIGCHLD, &act, 0);

  if (r < 0) {

    cout << "sigaction error: " << strerror(errno) << endl;

    exit(errno);

  }
}
int main(int argc, char *argv[])

{

  setupSig();

  for (int i = 0; i < sizeof(tcfgs)/sizeof(tcfg); i++) {

    //cout << tcfgs[i].java << " " << tcfgs[i].opts << endl;

    doit(tcfgs[i]);

  }

  return 0;

}