/*------------------------------------------------------*/
/* hpduplex.c	remote laser printer driver for HP	*/
/*    LaserJet4 with double-sided printing capability	*/
/*							*/
/* Put executable in /usr/lib/lpdfilters/hpduplex	*/
/*							*/
/* (Currently controlled by psi.ece.jhu.edu)		*/
/* (See /etc/printcap entry on psi)			*/
/*------------------------------------------------------*/

/*------------------------------------------------------*/
/*   Written by Philippe O. Pouliquen and Tim Edwards	*/
/*   Last modified: May 5, 1995				*/
/*------------------------------------------------------*/

/*----------------------------------------------------------------------------------*/
/* Only machine types I know how to compile for:  DEC and SGI.  Set appropriately.  */
/* (DEC is BSD, SGI is SYSV.)							    */
/*----------------------------------------------------------------------------------*/

/* #define DEC */
#define SGI

/*----------------------------------------------------------------------------------*/

#include <stdio.h>
#include <strings.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sgtty.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <errno.h>
#include <netdb.h>

/*----------------------------------------------------------------------------------*/
/* To force double-sided printing on and off for this file only:		    */
/*----------------------------------------------------------------------------------*/

char duplex_temp[] =
   "%!\r\nstatusdict begin true setduplexmode end\r\n"; 

/*----------------------------------------------------------------------------------*/
/* Note: to set double-sided printing on permanently, use:			    */
/*    char duplex_on[] =							    */
/*       "%!\r\nserverdict begin 0 exitserver statusdict begin true		    */
/*	  setduplexmode end\r\n"; 						    */
/*										    */
/* To set single-sided printing temporarily (hpsimplex), use:			    */
/*    char simplex_temp[] =							    */
/*       "%!\r\nstatusdict begin false setduplexmode end\r\n"; 			    */
/*										    */
/* And to set single-sided printing permanently, use:			    	    */
/*    char simplex_on[] =							    */
/*       "%!\r\nserverdict begin 0 exitserver statusdict begin false		    */
/*	  setduplexmode end\r\n"; 						    */
/*----------------------------------------------------------------------------------*/

#define fdin	0	/* File descriptor for standard input  */
#define fdout	1	/* File descriptor for standard output */

/*----------------------------------------------------------------------------------*/

main(argc,argv)
  int argc;
  char *argv[];
{
  int hp1, i = 0;
  struct sockaddr_in hp1_addr;
  char c;

  /* Set up internet connection to printer hp1 */

  if ((hp1 = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
    perror("Unable to create socket");
    exit(1);
  }

  hp1_addr.sin_family = AF_INET;
  hp1_addr.sin_port = htons(9100);

  /*------------------------------------*/
  /* hp1's inet address = 128.220.14.86 */
  /*  = hex 0x560EDC80			*/
  /*------------------------------------*/

#ifdef DEC
  hp1_addr.sin_addr.S_un.S_addr = 0x560EDC80;
#else
  hp1_addr.sin_addr.s_addr = 0x560EDC80;
#endif


  if (connect(hp1, &hp1_addr, sizeof(struct sockaddr_in)) < 0) {
    perror("Unable to connect to printer hp1");
    exit(1);
  }

  i = 1;
  if (setsockopt(hp1, IPPROTO_TCP, TCP_NODELAY, &i, sizeof(int)) < 0) {
    perror("setsockopt");
    goto end;
  }

  /* send duplex-temp announcement to hp1 */
  /* to set double-sided printing.	  */

  write(hp1, duplex_temp, strlen(duplex_temp));

  /*----------------------------------------------------------------*/
  /* Read characters from standard input; hp1 takes \r\n in place   */
  /* of newline. . . treat as a special case.			    */
  /*----------------------------------------------------------------*/

  for(;;) {
     if (read(fdin, &c, 1) == 0) break;
     if ((c != '\n') && (c != '\r'))
	write(hp1, &c, 1);
     else {
	c = '\r';
	write(hp1, &c, 1);
	c = '\n';
	write(hp1, &c, 1);
     }
  }

  ioctl(hp1, FIONREAD, &i);
  if (i < 0) {
     perror("ioctl(FIONREAD)");
     goto end;
  }
  else if (i > 0) {
     for (; i > 0; i--) {
        read(hp1, &c, 1);

        /* print newline and carriage-return as-is */

        if ((c == '\n') || (c == '\r')) write(fdout, &c, 1);

	/* otherwise, print control characters nicely */
	/* either in carat (^N) notation or octal ([\nnn]) */

	else if ((c < 32) || (c > 126)) {
	   i = c;
	   if (i < 32) {
	      c = '^';
	      write(fdout, &c, 1);
	      c = i + 64;
	      write(fdout, &c, 1);
	   }
	   else if (i > 126) {
	      c = '[';
	      write(fdout, &c, 1);
	      c = '\\';
	      write(fdout, &c, 1);

	      c = ((i & 0x00C0) >> 6) + 48;
	      write(fdout, &c, 1);
	      c = ((i & 0x0038) >> 3) + 48;
	      write(fdout, &c, 1);
	      c = ((i & 0x0007)) + 48;
	      write(fdout, &c, 1);

	      c = ']';
	      write(fdout, &c, 1);
	   }
	}
	else write(fdout, &c, 1);
     }
  }

end:
  close(hp1);

  /* send newline to stdout */

  c = '\n';
  write(fdout, &c, 1);
}