/*
 *-------------------- DD_ACCESS -------------------------------
 *
 * name:         DD_Access.c V4.0
 * author:       Alexander Grigoriev , Andrei Fedorov
 * Insitution:   IKI RAN lab.546 aug@afed.iki.rssi.ru
  * Description: Set of function for access to DD system
  *   Last revision:   Oct 10, 2002
 *  List of revisions:
 *                  March    1999  V1.0
 *                 20 Oct 1999 ; ShowTicket was corrected.   V2.0
 *                28 Oct 1999 ; Added LOGINS,ddcheck         V3.0
  *               Oct 10, 2002 - revised by A. Fedorov       V 4.0
 */
/*#define _XOPEN_SOURCE*/  /* for crypt function */

#define _XOPEN_SOURCE
#include <unistd.h>
#include <time.h>
#include <DD.h>
#include <netcdf.h>
#include <DD_comm.h>
#include <DD_Access.h>

/*=========== Global Variables ===============================*/
  size_t CashStart[2]={0L,0L};
  size_t CashCount[2]={1, MAXHOSTLENGTH};
  size_t CashCountInt[2]={1, 1};
  extern int Verbose;
  
/*############################################################################*/

/*----------------GETTICKET------------------------------------*/

/* Description: This function find the user data in user_cash.nc
 *              If O'k rewrite the line with new time.
 *              In case of a new user, remove the first line with 
 *              older time data then a current time + 4.5 hours.
                *
                Take 3 arguments: UserId, 
                                  IP-address(string,like "193.232.6.60\0") 
                                  DD_user_id(can see in user_info.nc)
                                  
                Returns 0 if O'k or NOPERMISSION  if error
                
                If DD_log_name equal NULL searching for UserId, IP-address
                If DD_log_name nonequal NULL searching for IP-address,DD_log_name*
                *
 */

int GetTicket(int UID, char *HostName, int DD_user_id)
  {
    char *ddbase;
    char refname[PATHLENGTH];
    int TicketID, Comp=1, Flag,OldFlag=0, Find=0, dltt;
    int CurIDID,HostID,TimeID, DD_id_ID;   /* Variable IDs in the NC ticket file */
    int TimeFinish;
    int Clock;
    char CurHostName[MAXHOSTLENGTH];
    int CurID, CurTime,DD_id, MemTime,OldestStart;  /* Values to read and write to ticket file */
    size_t CurCashStart[2]={0,0};
    size_t HostCount[2] = {1,MAXHOSTLENGTH};
    int ACCESS = NOPERMISSION;
    int status; /* Return value of any  NC routine */
    
    if(Verbose) fprintf(stderr,"GetTicket: UID = %d, HostName <%s>, DD_user_id = <%d> is going to work\n",UID, HostName,DD_user_id); 

/*------------- OpenUserNC ---------------------------------*/

   if((ddbase = getenv("DDBASE")) == NULL)
   {
      if(Verbose) fprintf(stderr,"GETTICKET:  No DDBASE environment.\n");
      return(ENVIRERROR);
   }
   strcpy(refname,ddbase);
   strcat(refname,TICKET_PATH);
   if(Verbose) fprintf(stderr,"GETTICKET: TICKET_PATH is %s \n",refname);

   if((status = nc_open(refname, NC_WRITE,&TicketID))  !=  NC_NOERR)
   {
      if(Verbose) fprintf(stderr,"GETTICKET:  %s\n", nc_strerror(status));
      return(NOUSERSFILE);
   }

/*------------------ Working with -------------------------------*/
     
   status = nc_inq_varid(TicketID,"id",&CurIDID);
   status = nc_inq_varid(TicketID,"host",&HostID);
   status = nc_inq_varid(TicketID,"time",&TimeID);
   status = nc_inq_varid(TicketID,"DD_id",&DD_id_ID);
   status = nc_sync(TicketID);

   Clock = (int)time(NULL);
 
 //  TimeFinish = Clock+16200;  // 4.5 hours
   TimeFinish = Clock+172800;  // 48 hours
   HostName[strlen(HostName)] = '\0';
   CashStart[0]=0;
   OldestStart = 0;
 
   do
   {
     status = nc_get_var1_int(TicketID, CurIDID, CashStart,&CurID);
     nc_get_var1_int(TicketID, DD_id_ID, CashStart,&DD_id);
     nc_get_vara_text(TicketID, HostID,CashStart,HostCount,CurHostName);
     nc_get_var1_int(TicketID, TimeID,CashStart,&CurTime);

     if(CashStart[0] == 0) MemTime=CurTime;
   
     Comp=strcmp(CurHostName,HostName);
       
     if((CurID == UID)&&(Comp == 0)&&(DD_id == DD_user_id))
     {
        CurCashStart[0]=CashStart[0];
        Find = 1;
     }
     dltt = (CurTime - MemTime);
     
     if((dltt < 0) && (CurHostName[0] != '\0'))
     {
        OldestStart=CashStart[0]; 
        MemTime = CurTime; 
     }

     CashStart[0]++;
   }
   while((Find != 1) && (CurHostName[0] != '\0') && (CashStart[0] < USERCASHLEN));

   if(Verbose) fprintf(stderr,"FINISH TIME : %ld\n",TimeFinish);
  
   CashStart[0]--;
  
   if(MemTime < Clock) {
   OldFlag = 1;
   }
    if(Find == 1)
   {
     nc_put_var1_int(TicketID,TimeID,CurCashStart,&TimeFinish);
     if(Verbose) fprintf(stderr,"User: ID = %d, DD_id = %d, HostName <%s> continue work.\n ",UID,DD_user_id,HostName); 
     ACCESS = 0;
   }
   else
   if(OldFlag == 1)
   {
      CashStart[0]=OldestStart;

      nc_put_var1_int(TicketID,CurIDID, CashStart,&UID);
      nc_put_var1_int(TicketID,DD_id_ID, CashStart,&DD_user_id);
      nc_put_vara_text(TicketID,HostID,CashStart,HostCount,HostName);
      nc_put_var1_int(TicketID,TimeID,CashStart,&TimeFinish);
      if(Verbose) fprintf(stderr,"User: ID = %d, DD_id = %d, \n HostName <%s> started work.\n ",UID,DD_user_id,HostName); 
      ACCESS = 0;
   }
   else
   if((CashStart[0]<USERCASHLEN) && (CurHostName[0] == '\0'))
   {
      nc_put_var1_int(TicketID,CurIDID, CashStart,&UID);
      nc_put_var1_int(TicketID,DD_id_ID, CashStart,&DD_user_id);
      nc_put_vara_text(TicketID,HostID,CashStart,HostCount,HostName);
      nc_put_var1_int(TicketID,TimeID,CashStart,&TimeFinish);
      if(Verbose) fprintf(stderr,"User: ID = %d, DD_id = %d, \n HostName <%s> started work.\n ",UID,DD_user_id,HostName); 
      ACCESS = 0;
   } 
   else {fprintf(stderr,"Too many members!\n");ACCESS = NOPERMISSION;}
  
 
   /*if((CurID == UID)&&(Comp == 0)) fprintf(stderr,"Exists...\n");*/
  
   nc_sync(TicketID);
   nc_close(TicketID);
      
return((int)ACCESS);     
}      

/*############################################################################*/

/*-------------------CHECK TICKET-----------------------*/ 

/* Description: This function check the user for accessability
 *              in user_info.nc file. Returns DD_id if O'k. 
 *              Returns NOPERMISSION in case of unaccessability, neagative value (DD_access.h)
 *              in case of error.
 */
      
int CheckTicket(char *NameUsr, char *Ticket)
{
   int i=0;
   int DD_id;
   int Right = NOPERMISSION;
   char salt[2],newkey[USRLENGTH];
  
   int UsrRefID;  /* ID of reference file which consists description of all users */
   char *ddbase;
   char refname[PATHLENGTH];
  
   int UserDimID,UserLenDimID,PasLenDimID;   /* ID of dimensions in NC file */
   int MemID, PasID;                                              /* ID of variables in NC file */
   size_t MaxRecords, UserLength, PasswdLength;   /* Dimensions */
   size_t start[2] = {0,0}, UserCount[2] = {1,0}, PasswdCount[2] = {1,0};
   static char UserDimName[] = "user", UserLenDimName[] = "UserLength";  /* Dimensions names */
   static char PasLenDimName[] = "PasswdLength";                                       /* Dimensions names */
   static char MemName[] = "member", PasName[] = "passwd";                      /* Variable Names */
   char PasChar[USRLENGTH],MemChar[USRLENGTH];
    int status;   /* Return of any NC call */

/*------------- Open User reference NC ---------------------------------*/
   if((ddbase = getenv("DDBASE")) == NULL)
   {
      if(Verbose) fprintf(stderr,"CHECKTICKET:  No DDBASE environment.\n");
      return(ENVIRERROR);
   }
   strcpy(refname,ddbase);
   strcat(refname,USERREFNAME);
   if(Verbose) fprintf(stderr," CHECHTICKET: PATH is %s \n",refname);
// sleep(40);
   if((status = nc_open(refname, NC_WRITE,&UsrRefID))  !=  NC_NOERR)
   {
      if(Verbose) fprintf(stderr,"CHECHTICKET:  %s\n", nc_strerror(status));
      return(NOUSERSFILE);
   }

/*------------------ Define all dimensions -------------------------------*/

   status = nc_inq_dimid(UsrRefID,UserDimName,&UserDimID);
   status = nc_inq_dimlen(UsrRefID, UserDimID,  &MaxRecords);
   status = nc_inq_dimid(UsrRefID,UserLenDimName,&UserLenDimID);
   status = nc_inq_dimlen(UsrRefID, UserLenDimID,  &UserLength);
   UserCount[1] = UserLength;
   status = nc_inq_dimid(UsrRefID,PasLenDimName,&PasLenDimID);
   status = nc_inq_dimlen(UsrRefID, PasLenDimID,  &PasswdLength);
   PasswdCount[1] = PasswdLength;

/*fprintf(stderr,"CheckTicket:Rec: %d %d %d\n",MaxRecords,UserLength,PasswdLength);*/
  
/*------------------ Define all variables ID -------------------------------*/
   status = nc_inq_varid(UsrRefID, MemName,&MemID);
   status = nc_inq_varid(UsrRefID, PasName,&PasID);
    
  
   for(i=0;i<MaxRecords;i++)
   {
      start[0]=(size_t)i;
      nc_get_vara_text(UsrRefID, MemID, start,UserCount, MemChar);

      if(strcmp(MemChar,NameUsr)==0)
      {
         nc_get_vara_text(UsrRefID, PasID, start, PasswdCount, PasChar);

         /*fprintf(stderr,"Your dd_id is %u\n",i);*/
         DD_id = i;
         Ticket[strlen(Ticket)]='\0';
         NameUsr[strlen(NameUsr)]='\0';
         newkey[PasswdLength-1]='\0';
       
         strncpy(salt,PasChar,2);

         strcpy(newkey,(char *)crypt(Ticket,salt));

         if(strcmp(PasChar,newkey) == 0) 
         {
            if(Verbose) fprintf(stderr,"User %s is logged in\n",NameUsr);
            Right = DD_id;
         }
         else
         {
            if(Verbose) fprintf(stderr,"for user %s permission denied.\n",NameUsr);
            Right = NOPERMISSION;
         }

         break;

      }
   }
   nc_close(UsrRefID);
return((int)Right); 
}

/*       
 *-------------------- SHOW TICKET -------------------------------*/
/* 
 * Description: Library function. Used by DD_Server. It reads the 
 *              content of user_ticket.nc file. Compares the information
 *              with your {id,hostname,DD_id,time}.
 *  If id and hostname(IP_address) and DD_id exists in table of registarated
 *  users, check the working time. If one has any time for work, returns 0,
 *  or a negative value "NOPERMISSION".
 *   It IS DD_Check !
 */
  
int ShowTicket(int userID, char *hostname, char *DD_name)
  {
    char *ddbase;
    char refname[PATHLENGTH];
    int TicketID;    /* Ticket file ID */
    int Comp=1, Time_is=0, Find=0;
    int CurIDID,HostID,TimeID, DD_id_ID;   /* NC variables ID */
    time_t Clock; 
    char CurHostName[MAXHOSTLENGTH];
    int CurID, CurTime, RefTime, DD_id;   /* Variables */
    size_t CurCashStart[2]={0,0};
    size_t HostCount[2] = {1,MAXHOSTLENGTH};
    int ServerReply = NOPERMISSION;
    int DD_user_id = -1;
    int status;   /* Return of any NC call */

   hostname[strlen(hostname)]='\0';
   DD_name[strlen(DD_name)]='\0';
   if((strcmp(DD_name,NONAME))!=0) DD_user_id = CheckID(DD_name);
 
/*------------- OpenUserNC ---------------------------------*/

   if((ddbase = getenv("DDBASE")) == NULL)
   {
      if(Verbose) fprintf(stderr,"SHOWTICKET:  No DDBASE environment.\n");
      return(ENVIRERROR);
   }
   strcpy(refname,ddbase);
   strcat(refname,TICKET_PATH);
   if(Verbose) fprintf(stderr,"SHOWTICKET: TICKET_PATH is %s \n",refname);

   if((status = nc_open(refname, NC_WRITE,&TicketID))  !=  NC_NOERR)
   {
      if(Verbose) fprintf(stderr,"SHOWTICKET:  %s\n", nc_strerror(status));
      return(NOUSERSFILE);
   }

/*------------------Info about source.file-------------------------------*/
   status = nc_inq_varid(TicketID,"id",&CurIDID);
   status = nc_inq_varid(TicketID,"host",&HostID);
   status = nc_inq_varid(TicketID,"time",&TimeID);
   status = nc_inq_varid(TicketID,"DD_id",&DD_id_ID);

   nc_sync(TicketID);
   CashStart[0]=0;

  do
   {
     status = nc_get_var1_int(TicketID, CurIDID, CashStart,&CurID);
     status = nc_get_var1_int(TicketID, DD_id_ID, CashStart,&DD_id);
     status = nc_get_vara_text(TicketID, HostID,CashStart,HostCount,CurHostName);
     status = nc_get_var1_int(TicketID, TimeID,CashStart,&CurTime);
 
     Comp=strcmp(CurHostName,hostname);
     if((strcmp(DD_name,NONAME)) == 0) DD_user_id = DD_id;

     if((CurID == userID) && (Comp == 0) && (DD_id == DD_user_id))
     {
        RefTime = CurTime;
        CurCashStart[0]=CashStart[0];
        Find = 1;
     }

     CashStart[0]++;
   }
   while((CurHostName[0] != '\0') && (CashStart[0] < USERCASHLEN));

   if(Find == 1)
   {
     CashStart[0]=CurCashStart[0];
     status = nc_get_var1_int(TicketID, CurIDID, CashStart,&CurID);
     status = nc_get_var1_int(TicketID, DD_id_ID, CashStart,&DD_id);
     status = nc_get_vara_text(TicketID, HostID,CashStart,HostCount,CurHostName);
     status = nc_get_var1_int(TicketID, TimeID,CashStart,&CurTime);
     if((strcmp(DD_name,NONAME))==0)  DD_user_id = (int)DD_id;
   }
   CashStart[0]--;
      
   Clock=(int)time(NULL);

   if(CurTime > Clock) Time_is = 1;

   if((Find == 1) && (Time_is == 1))
   {
     fprintf(stderr,"User: ID = %d, DD_id = %d, host %s, timework=%d, is connected. \n",CurID,DD_user_id,hostname,Time_is);   
     ServerReply = 0;
   }
   else {

         fprintf(stderr,"User: ID = %d, DD_id = %d, host %s, timework=%d, Permission denied!. \n",CurID,DD_user_id,hostname,Time_is);   
         ServerReply=NOPERMISSION;
         }
  
   nc_sync(TicketID);
   nc_close(TicketID);
   return ServerReply;
}      

/*       
 *------------------------ SETUSER -------------------------------*/
/* 
 * Description: Library function for client-server using.  
 *              Send ID, HostName to server.
 *              Compares the information with your {id,hostname}.
 *              Returns 1 if O'k, or a negative value in case 
 *              of "NOPERMISSION".
 *
 */
int SetUser(int UserID, char *HostName, char *LogName)
{

   int SocketID = -1; /* Global socket id for this communication session */
   static DD_data_t dd = {DD_CHAR,0,NULL,0,NULL};
   static caddr_t buf = NULL;
   static XDR xdrs;
   int cc,i, hostlen, ticketlen, userlen;
   int op = SHOWTICKETREQ;
   int SHOW_ACCESS;
   
   SHOW_ACCESS = NOPERMISSION;
 /*  fprintf(stderr,"after CLIENT int SetUser: SocketID = %d\n",SocketID);
   fprintf(stderr,"after CLIENT int SetUser: User = %d  Host %s\n",UserID,HostName);
 */  

/*------------------CONNECTION to SERVER---------------------------*/
/*
 * If no connection, connect to server, try to order data set and return
 * ID if OK or ErrorNumber if not
 */


 /*  fprintf(stderr,"Try to connect Server\n");*/
/* If there is no connection, try to get it */
   if(SocketID < 0)
       if((SocketID = GetSocket()) < 0) return(NOCONNECTION);
 /*  fprintf(stderr,"Server3 connected\n");*/
   
   
/*---------------------REQUEST TO SERVER-----------------------------*/

/* Check the HostName length */
   if(strlen(HostName) > MAXHOSTLENGTH) hostlen = MAXHOSTLENGTH;
   else hostlen = strlen(HostName);
   if(strlen(LogName) > USRLENGTH) userlen = USRLENGTH;
   else userlen = strlen(LogName);

/* Allocation memory and stream */
   buf = (caddr_t)malloc(REQUESTLENGTH);
   xdrmem_create(&xdrs, buf, REQUESTLENGTH, XDR_ENCODE);

/* Encoding the request */
   xdr_int(&xdrs,&op);
   xdr_int(&xdrs,&UserID);
   xdr_string(&xdrs, &HostName, hostlen);
   xdr_string(&xdrs, &LogName, userlen);
/* fprintf(stderr,"UserID, HostName  just more : %d %s\n",UserID,HostName);*/
/* Send request */
   if((cc = send(SocketID,buf,REQUESTLENGTH,0)) < 0)
   {
      perror("DD_GetTicket:");
      free(buf);
      xdr_destroy(&xdrs);
      return(REQSENDERR);
   }
   free(buf);
   xdr_destroy(&xdrs);

/* Get reply header */

   buf = (caddr_t)malloc(REPLYLENGTH);
   i =0;
   while(((cc = recv(SocketID,buf,REPLYLENGTH,0)) < 0) && (i < TRY)) i++;
   if(cc < 0)
   {
      perror("DD_SetUser:");
      free(buf);
      return(REPLYRECERR);
   }

   xdrmem_create(&xdrs, buf, REPLYLENGTH, XDR_DECODE);
   xdr_int(&xdrs,&SHOW_ACCESS);

   free(buf);
   xdr_destroy(&xdrs);
   shutdown(SocketID,2);
   close(SocketID);
   /*SocketID = -1;*/
/*  fprintf(stderr,"SetUser,End; UserID, HostName  just more : %d %s\n",UserID,HostName);
  fprintf(stderr,"SHOW_ACCES %d \n",SHOW_ACCESS);
*/ 
 if(Verbose) fprintf(stderr,"SetUser: ACCES = %d \n",SHOW_ACCESS);

return((int)SHOW_ACCESS);
}

/*############################################################################*/

/*-------------------CHECK ID-----------------------*/ 

/* Description: This function check the user name in user_info.nc file. 
 *              Returns DD_id if exists. 
 *              Returns OK, or NOPERMISSION, or an ERROR
 */
      
int CheckID(char *NameUsr)
{
   int i=0,Find=0;
   int DD_id = NOPERMISSION;
  
   int UsrRefID;   /* ID of NC file */
   char *ddbase;
   char refname[PATHLENGTH];
   int UserDimID,UserLenDimID;    /* Dimennsions ID */
   int MemID;                                    /* Variable ID */
   size_t MaxRecords, UserLength;   /* Dimensions */
   size_t start[2]= {0,0};
   size_t UserCount[2] = {1,0};
   char UserDimName[] = "user", UserLenDimName[] = "UserLength";   /*   Dimensions names */
   char MemName[] = "member";                                      /* Variable name */
   char MemChar[USRLENGTH];
   int status;
 
/*------------- Open User Reference file ---------------------------------*/
   if((ddbase = getenv("DDBASE")) == NULL)
   {
      if(Verbose) fprintf(stderr,"CHECKID:  No DDBASE environment.\n");
      return(ENVIRERROR);
   }
   strcpy(refname,ddbase);
   strcat(refname,USERREFNAME);
   if(Verbose) fprintf(stderr," CHECKID: PATH is %s \n",refname);

   if((status = nc_open(refname, NC_WRITE,&UsrRefID))  !=  NC_NOERR)
   {
      if(Verbose) fprintf(stderr,"CHECKID:  %s\n", nc_strerror(status));
      return(NOUSERSFILE);
   }

/*------------------ Define all dimensions -------------------------------*/

   status = nc_inq_dimid(UsrRefID,UserDimName,&UserDimID);
   status = nc_inq_dimlen(UsrRefID, UserDimID,  &MaxRecords);
   status = nc_inq_dimid(UsrRefID,UserLenDimName,&UserLenDimID);
   status = nc_inq_dimlen(UsrRefID, UserLenDimID,  &UserLength);
   UserCount[1] = UserLength;

/*fprintf(stderr,"CheckTicket:Rec: %d %d %d\n",MaxRecords,UserLength,PasswdLength);*/

/*------------------ Define all variables ID -------------------------------*/
   status = nc_inq_varid(UsrRefID, MemName,&MemID);

   while((i<MaxRecords) && (Find != 1))
   {
      start[0]=i;
      status = nc_get_vara_text(UsrRefID, MemID, start,UserCount,MemChar);
      if(strcmp(MemChar,NameUsr)==0) {DD_id = i;Find=1;}
      i++;
   }
   nc_close(UsrRefID);
   return(DD_id);
}

/*----------------Put into LOG file------------------------------------*/

/* Description: This function requires ID of local host, IP-address of 
*               local host and Login Name.      
*
*/

void Put2Log(int UID, char *Host, char *LogName, int error)
  {
    FILE *log;
    time_t Clock; 
    char *ddbase;
    char refname[PATHLENGTH], right[]="   normal    \0",noright[]="no permission\0";

   if((ddbase = getenv("DDBASE")) == NULL)
   {
      fprintf(stderr,"No DDBASE info. Check your profile... \n");
      return;
   }
   strcpy(refname,ddbase);
   strcat(refname,LOGFILE);
   if(Verbose) fprintf(stderr,"LOG file: %s \n",refname);
   if((log = fopen(refname, "a")) == NULL)
   {
      fprintf(stderr,"Error in opening log file. \n");
      return;
   }

   Clock=time(NULL);
   
   if(error>=0) 
   fprintf(log,"%s\t%s\t%u  %s\t%s",Host,LogName,UID,right,ctime(&Clock));
   else fprintf(log,"%s\t%s\t%u  %s\t%s",Host,LogName,UID,noright,ctime(&Clock));

   fclose(log);
 
   return;
 }
   
/*---------------------LOGINS----------------------------------*/

/* Description: This function uses by ddcheck */
/*              Compare two passwords  */
  
int LOGINS(char *password)
{
  char salt[3],newkey[13];
  char pas[80];
  char PName[]="Administrator password: ";
  int ACCESS_ = 0;

/*--------------Password----------------------------*/
  
   strncpy(salt,password,2);
   salt[2]='\0';
   strcpy(pas,getpass(PName));
   pas[strlen(pas)] = '\0';
   strcpy(newkey,(char *)crypt(pas,salt));
   newkey[strlen(newkey)] = '\0';
   if(strcmp(newkey, password) == 0) ACCESS_=1;

   return ACCESS_;
}

/*---------------------DDCHECK----------------------------------*/

/* Description: This function check user for dd administrator access to DD_System
*               Require only dd password from you.
*               Returns 0 if o'k or -1 in case of unaccessability.
*
*/
  
int ddcheck()
{
  int FL=1,coun,i;
  char lines[256],ref[40];
  FILE *files;

/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/
   files=fopen("/etc/passwd","r");
   while(FL != 0)
   { 
     if(fgets(lines, 255, files) != NULL)
     {
       coun=(strlen(lines)-strlen(strchr(lines,':')));
       strncpy(ref,lines,coun);
       ref[(strlen(lines)-strlen(strchr(lines,':')))]='\0';
       if(strcmp(ref,"dd") == 0)
       {
         coun=(strlen(&(lines[0])+3)-strlen(strchr(&(lines[0])+3,':')));
         strncpy(ref,&lines[0]+3,coun);
         ref[coun]='\0';
         i=LOGINS(ref);
       }

     }
     else FL=0;
   }
  fclose(files);
  if(i == 0) return(-1);
  return(0);
}
/*++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++*/