text: /* -*- c-indent-level: 2; c-continued-statement-offset: 2 -*- */ 
  /*
   * %CopyrightBegin%
   *
   * Copyright Ericsson AB 1998-2016. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   *
   * %CopyrightEnd%
   */
  
  #ifdef HAVE_CONFIG_H
  #  include "config.h"
  #endif
  #include "epmd.h"     /* Renamed from 'epmd_r4.h' */
  #include "epmd_int.h"
  #include "erl_printf.h"
  
  #ifdef HAVE_STDLIB_H
  #  include <stdlib.h>
  #endif
  #include <time.h>
  /* forward declarations */
  
  static void usage(EpmdVars *);
  static void run_daemon(EpmdVars*);
  static char* get_addresses(void);
  static int get_port_no(void);
  static int check_relaxed(void);
  #ifdef __WIN32__
  static int has_console(void);
  #endif
  
  #ifdef DONT_USE_MAIN
  
  static int epmd_main(int, char **, int);
  
  /* VxWorks fill 10 stack words with zero when a function is called
     from the shell. So it is safe to have argv and argc as parameters
     even if they are not given in the call. */
  
  #define MAX_DEBUG 10
  
  int epmd_dbg(int level,int port) /* Utility to debug epmd... */
  {
    char* argv[MAX_DEBUG+4];
    char  ibuff[100];
    int   argc = 0;
    
    argv[argc++] = "epmd";
    if(level > MAX_DEBUG)
      level = MAX_DEBUG;
    for(;level;--level)
      argv[argc++] = "-d";
    if(port)
      {
        argv[argc++] = "-port";
        erts_snprintf(ibuff, sizeof(ibuff), "%d",port);
        argv[argc++] = ibuff;
      }
    argv[argc] = NULL;
  
    return epmd(argc,argv);
  
  }
  
  static char *mystrdup(char *s)
  {
      char *r = malloc(strlen(s)+1);
      strcpy(r,s);
      return r;
  }
  
  #ifdef VXWORKS
  int start_epmd(a0, a1, a2, a3, a4, a5, a6, a7, a8, a9)
  char *a0, *a1, *a2, *a3, *a4, *a5, *a6, *a7, *a8, *a9;     
  {
    char*  argarr[] = {a0,a1,a2,a3,a4,a5,a6,a7,a8,a9};
    int    i;
    char** argv = malloc(sizeof(char *)*10);
    int    argvsiz = 10;
    int    argc = 1;
    char*  tmp = malloc(100);
    int    tmpsiz = 100;
    char*  pplast;
    char*  token;
    
    argv[0] = mystrdup("epmd");
    argv[1] = NULL;
    
    for(i=0;i<10;++i)
      {
        if(argarr[i] == NULL || *argarr[i] == '\0')
  	continue;
        if(strlen(argarr[i]) >= tmpsiz)
  	tmp = realloc(tmp, tmpsiz = (strlen(argarr[i])+1));
        strcpy(tmp,argarr[i]);
        for(token = strtok_r(tmp," ",&pplast);
  	  token != NULL;
  	  token = strtok_r(NULL," ",&pplast))
  	{
  	  if(argc >= argvsiz - 1)
  	    argv = realloc(argv,sizeof(char *) * (argvsiz += 10));
  	  argv[argc++] = mystrdup(token);
  	  argv[argc] = NULL;
  	}
      }
    free(tmp);
    return taskSpawn("epmd",100,VX_FP_TASK,20000,epmd_main,
  		   argc,(int) argv,1,
  		   0,0,0,0,0,0,0);
  }
  #endif    /* WxWorks */
  
  
  int epmd(int argc, char **argv)
  {
    return epmd_main(argc,argv,0);
  }
  
  static int epmd_main(int argc, char** argv, int free_argv)
  #else
  int main(int argc, char** argv)
  #endif /* DONT_USE_MAIN */
  {
      EpmdVars g_empd_vars;
      EpmdVars *g = &g_empd_vars;
      int i;
  #ifdef __WIN32__
      WORD wVersionRequested;
      WSADATA wsaData;
      int err;
  
      wVersionRequested = MAKEWORD(1, 1);
  
      err = WSAStartup(wVersionRequested, &wsaData);
      if (err != 0)
          epmd_cleanup_exit(g,1);
  
      if (LOBYTE(wsaData.wVersion) != 1 || HIBYTE(wsaData.wVersion ) != 1) {
          WSACleanup();
      	epmd_cleanup_exit(g,1);
      }
  #endif
  #ifdef DONT_USE_MAIN
      if(free_argv)
  	g->argv = argv;
      else 
  	g->argv = NULL;
  #else
      g->argv = NULL;
  #endif
  
      g->addresses      = get_addresses();
      g->port           = get_port_no();
      g->debug          = 0;
  
      g->silent         = 0; 
      g->is_daemon      = 0;
      g->brutal_kill    = check_relaxed();
      g->packet_timeout = CLOSE_TIMEOUT; /* Default timeout */
      g->delay_accept   = 0;
      g->delay_write    = 0;
      g->progname       = argv[0];
      g->conn           = NULL;
      g->nodes.reg = g->nodes.unreg = g->nodes.unreg_tail = NULL;
      g->nodes.unreg_count = 0;
      g->active_conn    = 0;
  #ifdef HAVE_SYSTEMD_DAEMON
      g->is_systemd     = 0;
  #endif /* HAVE_SYSTEMD_DAEMON */
  
      for (i = 0; i < MAX_LISTEN_SOCKETS; i++)
  	g->listenfd[i] = -1;
  
      argc--;
      argv++;
      while (argc > 0) {
  	if ((strcmp(argv[0], "-debug")==0) ||
  	    (strcmp(argv[0], "-d")==0)) {
  	    g->debug += 1;
  	    argv++; argc--;
  	} else if (strcmp(argv[0], "-packet_timeout") == 0) {
  	    if ((argc == 1) ||
  		((g->packet_timeout = atoi(argv[1])) == 0))
  		usage(g);
  	    argv += 2; argc -= 2;
  	} else if (strcmp(argv[0], "-delay_accept") == 0) {
  	    if ((argc == 1) ||
  		((g->delay_accept = atoi(argv[1])) == 0))
  		usage(g);
  	    argv += 2; argc -= 2;
  	} else if (strcmp(argv[0], "-delay_write") == 0) {
  	    if ((argc == 1) ||
  		((g->delay_write = atoi(argv[1])) == 0))
  		usage(g);
  	    argv += 2; argc -= 2;
  	} else if (strcmp(argv[0], "-daemon") == 0) {
  	    g->is_daemon = 1;
  	    argv++; argc--;
  	} else if (strcmp(argv[0], "-relaxed_command_check") == 0) {
  	    g->brutal_kill = 1;
  	    argv++; argc--;
  	} else if (strcmp(argv[0], "-kill") == 0) {
  	    if (argc == 1)
  		kill_epmd(g);
  	    else
  		usage(g);
  	    epmd_cleanup_exit(g,0);
  	} else if (strcmp(argv[0], "-address") == 0) {
  	    if (argc == 1)
  	      usage(g);
  	    g->addresses = argv[1];
  	    argv += 2; argc -= 2;
  	} else if (strcmp(argv[0], "-port") == 0) {
  	    if ((argc == 1) ||
  		((g->port = atoi(argv[1])) == 0))
  	      usage(g);
  	    argv += 2; argc -= 2;
  	} else if (strcmp(argv[0], "-names") == 0) {
  	    if (argc == 1)
  		epmd_call(g, EPMD_NAMES_REQ);
  	    else
  		usage(g);
  	    epmd_cleanup_exit(g,0);
  	} else if (strcmp(argv[0], "-started") == 0) {
  	    g->silent = 1;
  	    if (argc == 1)
  		epmd_call(g, EPMD_NAMES_REQ);
  	    else
  		usage(g);
  	    epmd_cleanup_exit(g,0);
  	} else if (strcmp(argv[0], "-dump") == 0) {
  	    if (argc == 1)
  		epmd_call(g, EPMD_DUMP_REQ);
  	    else
  		usage(g);
  	    epmd_cleanup_exit(g,0);
  	} else if (strcmp(argv[0], "-stop") == 0) {
  	    if (argc == 2)
  		stop_cli(g, argv[1]);
  	    else
  		usage(g);
  	    epmd_cleanup_exit(g,0);
  #ifdef HAVE_SYSTEMD_DAEMON
  	} else if (strcmp(argv[0], "-systemd") == 0) {
              g->is_systemd = 1;
              argv++; argc--;
  #endif /* HAVE_SYSTEMD_DAEMON */
  	} else
  	    usage(g);
      }
      dbg_printf(g,1,"epmd running - daemon = %d",g->is_daemon);
  
  #ifndef NO_SYSCONF
      if ((g->max_conn = sysconf(_SC_OPEN_MAX)) <= 0)
  #endif
        g->max_conn = MAX_FILES;
    
      /*
       * max_conn must not be greater than FD_SETSIZE.
       * (at least QNX crashes)
       */
    
      if (g->max_conn > FD_SETSIZE) {
        g->max_conn = FD_SETSIZE;
      }
  
      if (g->is_daemon)  {
  	run_daemon(g);
      } else {
  	run(g);
      }
      return 0;
  }
  
  #ifndef NO_DAEMON
  static void run_daemon(EpmdVars *g)
  {
      register int child_pid, fd;
      
      dbg_tty_printf(g,2,"fork a daemon");
  
      /* fork to make sure first child is not a process group leader */
      if (( child_pid = fork()) < 0)
        {
  #ifdef HAVE_SYSLOG_H
  	syslog(LOG_ERR,"erlang mapper daemon cant fork %m");
  #endif
  	epmd_cleanup_exit(g,1);
        }
      else if (child_pid > 0)
        {
  	dbg_tty_printf(g,2,"daemon child is %d",child_pid);
  	epmd_cleanup_exit(g,0);  /*parent */
        }
      
      if (setsid() < 0)
        {
  	dbg_perror(g,"epmd: Cant setsid()");
  	epmd_cleanup_exit(g,1);
        }
  
      /* ???? */
  
  
      signal(SIGHUP, SIG_IGN);
  
      /* We don't want to be session leader so we fork again */
  
      if ((child_pid = fork()) < 0)
        {
  #ifdef HAVE_SYSLOG_H
  	syslog(LOG_ERR,"erlang mapper daemon cant fork 2'nd time %m");
  #endif
  	epmd_cleanup_exit(g,1);
        }
      else if (child_pid > 0)
        {
  	dbg_tty_printf(g,2,"daemon 2'nd child is %d",child_pid);
  	epmd_cleanup_exit(g,0);  /*parent */
        }
  
      /* move cwd to root to make sure we are not on a mounted filesystem  */
      if (chdir("/") < 0)
        {
  	dbg_perror(g,"epmd: chdir() failed");
  	epmd_cleanup_exit(g,1);
        }
      
      umask(0);
  
      for (fd = 0; fd < g->max_conn ; fd++) /* close all files ... */
          close(fd);
      /* Syslog on linux will try to write to whatever if we dont
         inform it that the log is closed. */
      closelog();
  
      /* These shouldn't be needed but for safety... */
  
      open("/dev/null", O_RDONLY); /* Order is important! */
      open("/dev/null", O_WRONLY);
      open("/dev/null", O_WRONLY);
  
      errno = 0;  /* if set by open */
  
      run(g);
  }
  
  #endif /* NO_DAEMON */    
  
  #ifdef __WIN32__
  static int has_console(void)
  {
      HANDLE handle = CreateFile("CONOUT$", GENERIC_WRITE, FILE_SHARE_WRITE,
  			       NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
  
      if (handle == INVALID_HANDLE_VALUE) {
  	return 0;
      } else {
          CloseHandle(handle);
  	return 1;
      }
  }
  
  static void run_daemon(EpmdVars *g)
  {
      if (has_console()) {
  	if (spawnvp(_P_DETACH, __argv[0], __argv) == -1) {
  	    fprintf(stderr, "Failed to spawn detached epmd\n");
  	    exit(1);
  	}
  	exit(0);
      }
  
      close(0);
      close(1);
      close(2);
  
      /* These shouldn't be needed but for safety... */
  
      open("nul", O_RDONLY);
      open("nul", O_WRONLY);
      open("nul", O_WRONLY);
  
      run(g);
  }
  #endif
  
  #if defined(VXWORKS)
  static void run_daemon(EpmdVars *g)
  {
      run(g);
  }
  #endif
  
  
  /***************************************************************************
   *  Misc support routines
   *
   */
  
  static void usage(EpmdVars *g)
  {
      fprintf(stderr, "usage: epmd [-d|-debug] [DbgExtra...] [-address List]\n");
      fprintf(stderr, "            [-port No] [-daemon] [-relaxed_command_check]\n");
      fprintf(stderr, "       epmd [-d|-debug] [-port No] [-names|-kill|-stop name]\n\n");
      fprintf(stderr, "See the Erlang epmd manual page for info about the usage.\n\n");
      fprintf(stderr, "Regular options\n");
      fprintf(stderr, "    -address List\n");
      fprintf(stderr, "        Let epmd listen only on the comma-separated list of IP\n");
      fprintf(stderr, "        addresses (and on the loopback interface).\n");
      fprintf(stderr, "    -port No\n");
      fprintf(stderr, "        Let epmd listen to another port than default %d\n",
  	    EPMD_PORT_NO);
      fprintf(stderr, "    -d\n");
      fprintf(stderr, "    -debug\n");
      fprintf(stderr, "        Enable debugging. This will give a log to\n");
      fprintf(stderr, "        the standard error stream. It will shorten\n");
      fprintf(stderr, "        the number of saved used node names to 5.\n\n");
      fprintf(stderr, "        If you give more than one debug flag you may\n");
      fprintf(stderr, "        get more debugging information.\n");
      fprintf(stderr, "    -daemon\n");
      fprintf(stderr, "        Start epmd detached (as a daemon)\n");
      fprintf(stderr, "    -relaxed_command_check\n");
      fprintf(stderr, "        Allow this instance of epmd to be killed with\n");
      fprintf(stderr, "        epmd -kill even if there "
  	    "are registered nodes.\n");
      fprintf(stderr, "        Also allows forced unregister (epmd -stop).\n");
  #ifdef HAVE_SYSTEMD_DAEMON
      fprintf(stderr, "    -systemd\n");
      fprintf(stderr, "        Wait for socket from systemd. The option makes sense\n");
      fprintf(stderr, "        when started from .socket unit.\n");
  #endif /* HAVE_SYSTEMD_DAEMON */
      fprintf(stderr, "\nDbgExtra options\n");
      fprintf(stderr, "    -packet_timeout Seconds\n");
      fprintf(stderr, "        Set the number of seconds a connection can be\n");
      fprintf(stderr, "        inactive before epmd times out and closes the\n");
      fprintf(stderr, "        connection (default 60).\n\n");
      fprintf(stderr, "    -delay_accept Seconds\n");
      fprintf(stderr, "        To simulate a busy server you can insert a\n");
      fprintf(stderr, "        delay between epmd gets notified about that\n");
      fprintf(stderr, "        a new connection is requested and when the\n");
      fprintf(stderr, "        connections gets accepted.\n\n");
      fprintf(stderr, "    -delay_write Seconds\n");
      fprintf(stderr, "        Also a simulation of a busy server. Inserts\n");
      fprintf(stderr, "        a delay before a reply is sent.\n");
      fprintf(stderr, "\nInteractive options\n");
      fprintf(stderr, "    -names\n");
      fprintf(stderr, "        List names registered with the currently "
  	    "running epmd\n");
      fprintf(stderr, "    -kill\n");
      fprintf(stderr, "        Kill the currently running epmd\n");
      fprintf(stderr, "        (only allowed if -names show empty database or\n");
      fprintf(stderr, "        -relaxed_command_check was given when epmd was started).\n");
      fprintf(stderr, "    -stop Name\n");
      fprintf(stderr, "        Forcibly unregisters a name with epmd\n");
      fprintf(stderr, "        (only allowed if -relaxed_command_check was given when \n");
      fprintf(stderr, "        epmd was started).\n");
      epmd_cleanup_exit(g,1);
  }
  
  /***************************************************************************
   *  Error reporting - dbg_printf() & dbg_tty_printf & dbg_perror()
   *
   *  The first form will print out on tty or syslog depending on
   *  if it runs as daemon or not. The second form will never print
   *  out on syslog.
   *
   *  The arguments are
   *
   *      g            Epmd variables
   *      from_level   From what debug level we print. 0 means always.
   *                   (This argument is missing from dbg_perror() )
   *      format       Format string
   *      args...      Arguments to print out according to the format
   *      
   */
  #define DEBUG_BUFFER_SIZE 2048
  static void dbg_gen_printf(int onsyslog,int perr,int from_level,
  			   EpmdVars *g,const char *format, va_list args)
  {
    time_t now;
    char *timestr;
    char buf[DEBUG_BUFFER_SIZE];
  
    if (g->is_daemon)
      {
  #ifdef HAVE_SYSLOG_H
        if (onsyslog)
  	{
  	  erts_vsnprintf(buf, DEBUG_BUFFER_SIZE, format, args);
  	  syslog(LOG_ERR,"epmd: %s",buf);
  	}
  #endif
      }
    else
      {
        int len;
  
        time(&now);
        timestr = (char *)ctime(&now);
        erts_snprintf(buf, DEBUG_BUFFER_SIZE, "epmd: %.*s: ",
  		    (int) strlen(timestr)-1, timestr);
        len = strlen(buf);
        erts_vsnprintf(buf + len, DEBUG_BUFFER_SIZE - len, format, args);
        if (perr != 0)
  	fprintf(stderr,"%s: %s\r\n",buf,strerror(perr));
        else
  	fprintf(stderr,"%s\r\n",buf);
      }
  }
  
  
  void dbg_perror(EpmdVars *g,const char *format,...)
  {
    va_list args;
    va_start(args, format);
    dbg_gen_printf(1,errno,0,g,format,args);
    va_end(args);
  }
  
  
  void dbg_tty_printf(EpmdVars *g,int from_level,const char *format,...)
  {
    if (g->debug >= from_level) {
      va_list args;
      va_start(args, format);
      dbg_gen_printf(0,0,from_level,g,format,args);
      va_end(args);
    }
  }
  
  void dbg_printf(EpmdVars *g,int from_level,const char *format,...)
  {
    if (g->debug >= from_level) {
      va_list args;
      va_start(args, format);
      dbg_gen_printf(1,0,from_level,g,format,args);
      va_end(args);
    }
  }
  
  
  /***************************************************************************
   *
   * This function is to clean up all filedescriptors and free up memory on 
   * VxWorks.
   * This function exits, there is nothing else to do when all here is run.
   *
   */
  
  static void free_all_nodes(EpmdVars *g)
  {
      Node *tmp;
      for(tmp=g->nodes.reg; tmp != NULL; tmp = g->nodes.reg){
  	g->nodes.reg = tmp->next;
  	free(tmp);
      }
      for(tmp=g->nodes.unreg; tmp != NULL; tmp = g->nodes.unreg){
  	g->nodes.unreg = tmp->next;
  	free(tmp);
      }
  }
  void epmd_cleanup_exit(EpmdVars *g, int exitval)
  {
    int i;
  
    if(g->conn){
        for (i = 0; i < g->max_conn; i++)
  	  if (g->conn[i].open == EPMD_TRUE)
  	      epmd_conn_close(g,&g->conn[i]);
        free(g->conn);
    }
    for(i=0; i < MAX_LISTEN_SOCKETS; i++)
        if(g->listenfd[i] >= 0)
            close(g->listenfd[i]);
    free_all_nodes(g);
    if(g->argv){
        for(i=0; g->argv[i] != NULL; ++i)
  	  free(g->argv[i]);
        free(g->argv);
    }
  #ifdef HAVE_SYSTEMD_DAEMON
    if (g->is_systemd){
      sd_notifyf(0, "STATUS=Exited.\n"
                 "ERRNO=%i", exitval);
    }
  #endif /* HAVE_SYSTEMD_DAEMON */
    exit(exitval);
  }
  
  static char* get_addresses(void)
  {
      return getenv("ERL_EPMD_ADDRESS");
  }
  static int get_port_no(void)
  {
      char* port_str = getenv("ERL_EPMD_PORT");
      return (port_str != NULL) ? atoi(port_str) : EPMD_PORT_NO;
  }
  static int check_relaxed(void)
  {
      char* port_str = getenv("ERL_EPMD_RELAXED_COMMAND_CHECK");
      return (port_str != NULL) ? 1 : 0;
  }
  
  