/* Net2file.c 
 * Call me Net2file.  I accept a connection from a Mark-5 machine and 
 * write the received data to a file.  I'll try to create this file if 
 * necessary or append.  You should start me first, then command 
 * disc2net or in2net in the Mark-5 machine.  Command-line options: 
 *    -f    File name, default save.data 
 *    -r    Socket rcvbufs, default 0 = OS default 
 *    -p    Protocol, tcp or udp, default tcp 
 *    -d    Data port, default m5data 
 *    -m    Msglev, default 1 
 *    -h    Help 
 * You can watch how I'm doing with an 
 *    ls  -l  filename 
 * but this will lag the actual progress because of buffering.  I will 
 * end when the Mark-5 sending socket disconnects, or end me with ^C, 
 * after which filename will be ready to use.  Note that m5data tcp 
 * or udp needs to be in /etc/services on this machine.  Copy from a 
 * Mark-5 machine if need be.  This version of Net2file.c compiles 
 * with gcc on Linux or HP-UX and also with cc -Ae on HP-UX.  It won't 
 * compile with g++ without some mods.  This version now supports file 
 * sizes larger than 2 Gbytes.  Revised:  2005 May 14, JAB */ 
#define _LARGEFILE_SOURCE /* Large File Support (LFS) */ 
#define _LARGEFILE64_SOURCE 
#include <stdio.h>
#include <string.h> /* For strrchr() */ 
#include <stdlib.h> /* For atoi() */ 
#include <sys/types.h> /* For open(), socket(), connect(), etc. */ 
#include <sys/stat.h> /* For open(), fchmod(), etc. */ 
#include <unistd.h> /* For fcntl() */ 
#include <fcntl.h> /* For open() and fcntl() */ 
#include <sys/socket.h> /* For socket(), connect(), etc. */
#include <netinet/in.h> /* For socket() with PF_INET, etc. */
#include <netdb.h> /* For getservbyname() */
#define TRUE  1 
#define FALSE 0 
char * me; /* My name */
int msglev = 1; /* Debug level, default */

int main(int argc, char * argv[]) { /* Net2file */
  int port, sock, sock2, k, len, type, tof, on; 
  char * filename = "save.data"; /* File name default */ 
  char * dataport = "m5data"; /* Data port default */ 
  char * smod = "tcp"; /* Protocol default */ 
  unsigned int rcvbuf, rcvbufs = 0; /* Receive buffer size */ 
      /* (Don't confuse these two) */ 
  socklen_t optlen; /* For getsockopt() */ 
  FILE * file; 
  struct servent * set; /* From getservbyname() */
  struct sockaddr_in socaddin;	/* For bind() socket info */
  struct sockaddr_in socadd; /* For accept() socket info */
  int kk; /* For accept() (should be socklen_t) */ 
  unsigned long rbuff[131072]; /* For data */ 

  /* *** Initialize *** */
  me = (me = strrchr(argv[0], '/')) == NULL ? argv[0] : me+1; /* My name */ 
  /* Parse command-line options, if any */ 
  k = 0; 
  while (k >= 0) { 
    switch (k = getopt(argc, argv, "hf:r:p:d:m:")) { 
    /* That's help, filename, rcvbufs, protocol, msglev */ 
      case 'h' : /* Help */ 
        (void) fprintf(stderr, 
             "%s USAGE: \n    %s -f <f> -r <r> -p <p> -d <d> -m <m> -h \n" 
             " where <f> is file name, default save.data, \n" 
             "       <r> is socket rcvbufs, bytes, OS default, \n" 
             "       <p> is protocol, tcp or udp, default tcp, \n" 
             "       <d> is data port, default m5data, \n" 
             "       <m> is message level, default 1, \n" 
             "    and -h shows this help message. \n", me, me); 
        return(0); /* End here */ 
        break; /* (Not used) */ 
      case 'm' : /* msglev */ 
        /* msglev = -1 Vast quantities of debuggery prints
         * msglev =  0 Some debuggery prints
         * msglev =  1 Default and normal operation; warnings and errors print
         * msglev =  2 Only errors and operational messages print
         * msglev =  3 Nothing prints except fatal errors when program dies
         * (default 1 above) */
        msglev = atoi(optarg); /* (No check) */
        if (msglev < 1) /* Debuggery? */
          (void) fprintf(stderr, /* Yes */
              "%s DEBUG:  msglev set to %d \n", me, msglev);
        break;
      case 'f' : /* File name */ 
        filename = optarg; 
        break; 
      case 'r' : /* rcvbufs */ 
        rcvbufs = atoi(optarg); /* Yes */ 
        break; 
      case 'p' : /* Protocol */ 
        smod = optarg; /* Yes */ 
        break; 
      case 'd' : /* Data port */ 
        dataport = optarg; 
        break; 
      case '?' : /* Error:  character not in list */
        if (msglev < 2) /* Debuggery? */
          (void) fprintf(stderr, /* Yes */
              "%s WARNING:  Unknown option on command line \n", me);
        break;
      case ':' : /* Error:  missing numerical parameter */
        if (msglev < 2) /* Debuggery? */
          (void) fprintf(stderr, /* Yes */
              "%s WARNING:  Missing number on command line \n", me);
        break;
      default : /* Probably -1, end of parameters */
        break;
      } /* End of switch on k */
    } /* End of while k */
  /* ** Open or create output file ** */
  if ((port = open64(filename, O_WRONLY | O_CREAT)) < 0) { /* OK? */
    (void) fprintf(stderr, "%s ERROR: \007 Can't open() file ", me); /* Nope */ 
    perror(filename); 
    return(-1); /* Error */ } 
  (void) fchmod(port, 0664); /* Ignore errors (e.g., owned by someone else) */ 
  /* Open this output file also as a stream */ 
  if ((file = fdopen(port, "a")) == NULL) { /* OK? */
    (void) fprintf(stderr, "%s ERROR: \007 Can't fdopen() file ", me); /* No */ 
    perror(filename); 
    return(-2); /* Error */ } 
  if (msglev < 1) /* Debuggery? */ 
    (void) fprintf(stderr, /* Yes */ 
        "%s DEBUG:  Opened file %s \n", me, filename); 
  /* ** Create and configure a socket to receive data ** */ 
  if (strcasecmp(smod, "tcp") == 0) /* tcp? */
    type = SOCK_STREAM; /* Yes */
  else if (strcasecmp(smod, "udp") == 0) /* udp? */
    type = SOCK_DGRAM; /* Yes */
  else { /* Neither tcp nor udp is an error */
    (void) fprintf(stderr, /* Yes */
        "%s ERROR:  Can't do type %s \n", me, smod);
    return(-3); /* Error */ } 
  if ((sock = socket(PF_INET, type, 0)) < 0) { /* OK? */
    (void) fprintf(stderr, /* Nope */
        "%s ERROR: \007 socket() returned %d ", me, sock);
    perror("error");
    return(-4); /* Error */ } 
  if (msglev < 1) /* Debuggery? */ 
    (void) fprintf(stderr, /* Yes */ 
        "%s DEBUG:  Opened %s socket %d \n", me, smod, sock); 
  /* If tcp, then we set keep-alive in case a firewall needs it */ 
  if (type == SOCK_STREAM) { /* tcp? */ 
    tof = TRUE; /* Yes */ 
    if(setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, &tof, sizeof(int)) < 0) { 
        /* Set keep-alive, OK? */ 
      (void) fprintf(stderr, /* Nope */ 
            "%s ERROR: \007 setsockopt() SO_KEEPALIVE returned ", me); 
      perror("error"); 
      return(-5); /* Error */ } } 
  /* SO_RCVBUF sets or gets the maximum socket receive buffer in bytes.
   * The default value is set by the rmem_default sysctl, and the
   * maximum allowed value is set by the rmem_max sysctl. */ 
  if (rcvbufs > 0) { /* Change SO_RCVBUF? */
    if(setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *) &rcvbufs,
        sizeof(rcvbufs)) < 0) { /* Yes, socket receive-buffer size, OK? */
      if (msglev < 2) { /* Nope.  Debuggery? */
        (void) fprintf(stderr, /* Yes */
            "%s WARNING:  setsockopt() SO_RCVBUF %d returned ", me, rcvbufs);
        perror("error"); } /* Error, but we try to go on */ }
    } /* End of if change SO_RCVBUF */ 
  if (msglev < 1) /* Debuggery? */ { 
    optlen = sizeof(unsigned int); /* Yes */ 
    (void) getsockopt(sock, SOL_SOCKET, SO_RCVBUF, 
        (void *) &rcvbuf, &optlen); /* Socket receive-buffer size */ 
    (void) fprintf(stderr, "%s DEBUG:  rcvbufs is %u bytes \n", me, rcvbuf); } 
  /* Get service number for data port socket service */
    if ((set = getservbyname(dataport, smod)) == NULL) { /* OK? */ 
    (void) fprintf(stderr, /* Nope */
        "%s ERROR: \007 %s %s not found in /etc/services \n", 
        me, dataport, smod);
    return(-6); /* Error */ } 
  /* Allow reuse of the local socket address in bind() */
  on = TRUE;
  if(setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *) &on,
      sizeof(int)) < 0) { /* OK? */
    if (msglev < 2) { /* Nope.  Debuggery? */
      (void) fprintf(stderr, /* Yes */
          "%s WARNING: \007 setsockopt() SO_REUSEADDR returned ", me);
      perror("error"); } /* Error, but we try to go on */ }
  /* Set configuration for bind() */ 
  socaddin.sin_port = set->s_port; /* Port service's number */ 
  if (msglev < 1) /* Debuggery? */
    /* Yes.  For Intelendian, we need to swap bytes in set->s_port */
    (void) fprintf(stderr, "%s DEBUG:  %s %s port is %d \n", 
        me, dataport, smod, ntohs(socaddin.sin_port));
  socaddin.sin_family = PF_INET; /* To agree with socket() above */
  socaddin.sin_addr.s_addr = INADDR_ANY; /* From any network address */ 
  /* Bind this socket to service */
  if ((k = bind(sock, (struct sockaddr *) &socaddin,
      sizeof(struct sockaddr_in))) < 0) { /* OK? */
    (void) fprintf(stderr, "%s ERROR: \007 bind() returned %d ", me, k); 
    perror("error");
    return(-7); /* Error */ } 
  if (msglev < 1) /* Debuggery? */ 
    (void) fprintf(stderr, /* Yes */ 
        "%s DEBUG:  Socket %d bound to %s %s \n", me, sock, dataport, smod); 
  /* Listen for connections on this socket */
  if (type == SOCK_STREAM && (k = listen(sock, 3)) < 0) { /* OK? */
    (void) fprintf(stderr, "%s  ERROR: \007 listen() returned %d ", me, k);
    perror("error");
    return(-8); /* Error */ } 
  if (msglev < 1) /* Debuggery? */ 
    (void) fprintf(stderr, /* Yes */ 
        "%s DEBUG:  Listening for connections on socket %d \n", me, sock); 
  /* Accept a connection on this socket */ 
  if (type == SOCK_STREAM) { /* tcp? */ 
    kk = sizeof(struct sockaddr_in); 
    if (msglev < 1) /* Debuggery? */ 
      (void) fprintf(stderr, "%s DEBUG:  Waiting on accept() \n", me); 
    /* (We usually hang here waiting for the Mark-5 machine to connect) */ 
    if ((sock2 = accept(sock, (struct sockaddr *) &socadd, &kk)) < 0) { 
      (void) fprintf(stderr, "%s ERROR: \007 accept() returned %d ", 
          me, sock2);
      perror("error"); 
      return(-9); /* Error */ } 
    /* Here we have an accept on the data socket and a new socket */
    if (msglev < 1) /* Debuggery? */
      (void) fprintf(stderr, "%s DEBUG:  Got accept() on sock %d, sock2 %d \n", 
          me, sock, sock2); 
    (void) close(sock); /* Accept no more connections */ } 
  else { /* udp */ 
    sock2 = sock; 
    if (msglev < 1) /* Debuggery? */ 
      (void) fprintf(stderr, /* Yes */ 
          "%s DEBUG:  Ready to read %s data on socket %d \n", 
          me, smod, sock); } 
  /* ** Read data from this socket and write to file ** */ 
  while (1) { /* Loop until break */ 
    /* Read data from socket */ 
    len = recv(sock2, (void *) rbuff, sizeof(rbuff), 0);
    /* Check for errors or disconnect */
    if (len < 0) { /* Errors? */
      (void) fprintf(stderr, /* Yes */
          "%s ERROR:  recv() on sock2 %d returned %d ", me, sock2, len);
      perror("error"); 
      return(-10); /* Error */ }  
    if (len == 0) { /* Mark-5 disconnect? */ 
      if (msglev < 0) /* Yes.  Debuggery? */ 
        (void) fprintf(stderr, " \n"); /* Yes */ 
      if (msglev < 1) /* More debuggery? */
        (void) fprintf(stderr, /* Yes */
            "%s DEBUG:  recv() on sock2 %d returned %d; closing \n", 
            me, sock2, len); 
      break; /* Out of while loop until break */ } 
    /* Else OK, write data to file */ 
    if ((k = fwrite((void *) rbuff, len, 1, file)) != 1) { /* OK? */ 
      (void) fprintf(stderr, /* Nope */
          "%s ERROR:  fwrite() on %s returned %d ", me, filename, k);
      perror("error"); 
      return(-11); /* Error */ } 
    if (msglev < 0) /* Debuggery? */ 
      (void) fprintf(stderr, "#"); /* Yes */ 
    } /* End of while loop until break */ 
  (void) fprintf(stderr, "%s:  The End \n", me); 
  return(0); /* Normal end */ 
  } /* End of main() = Net2file */