/* Copyright (C) 1989, 2000 Aladdin Enterprises.  All rights reserved.
  
  This file is part of AFPL Ghostscript.
  
  AFPL Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author or
  distributor accepts any responsibility for the consequences of using it, or
  for whether it serves any particular purpose or works at all, unless he or
  she says so in writing.  Refer to the Aladdin Free Public License (the
  "License") for full details.
  
  Every copy of AFPL Ghostscript must include a copy of the License, normally
  in a plain ASCII text file named PUBLIC.  The License grants you the right
  to copy, modify and redistribute AFPL Ghostscript, but only under certain
  conditions described in the License.  Among other things, the License
  requires that the copyright notice and this notice be preserved on all
  copies.
*/

/*$Id: gp_unix.c,v 1.5 2001/04/08 08:43:24 ghostgum Exp $ */
/* Unix-specific routines for Ghostscript */
#include "pipe_.h"
#include "string_.h"
#include "time_.h"
#include "gx.h"
#include "gsexit.h"
#include "gp.h"

/*
 * This is the only place in Ghostscript that calls 'exit'.  Including
 * <stdlib.h> is overkill, but that's where it's declared on ANSI systems.
 * We don't have any way of detecting whether we have a standard library
 * (some GNU compilers perversely define __STDC__ but don't provide
 * an ANSI-compliant library), so we check __PROTOTYPES__ and
 * hope for the best.  We pick up getenv at the same time.
 */
#ifdef __PROTOTYPES__
#  include <stdlib.h>		/* for exit and getenv */
#else
extern void exit(P1(int));
extern char *getenv(P1(const char *));

#endif

/* Do platform-dependent initialization. */
void
gp_init(void)
{
}

/* Do platform-dependent cleanup. */
void
gp_exit(int exit_status, int code)
{
}

/* Exit the program. */
void
gp_do_exit(int exit_status)
{
}

/* ------ Miscellaneous ------ */

/* Get the string corresponding to an OS error number. */
/* Unix systems support this so inconsistently that we don't attempt */
/* to figure out whether it's available. */
const char *
gp_strerror(int errnum)
{
    return NULL;
}

/* ------ Date and time ------ */

/* Read the current time (in seconds since Jan. 1, 1970) */
/* and fraction (in nanoseconds). */
void
gp_get_realtime(long *pdt)
{
    struct timeval tp;

#if gettimeofday_no_timezone	/* older versions of SVR4 */
    {
	if (gettimeofday(&tp) == -1) {
	    lprintf("Ghostscript: gettimeofday failed!\n");
	    tp.tv_sec = tp.tv_usec = 0;
	}
    }
#else /* All other systems */
    {
	struct timezone tzp;

	if (gettimeofday(&tp, &tzp) == -1) {
	    lprintf("Ghostscript: gettimeofday failed!\n");
	    tp.tv_sec = tp.tv_usec = 0;
	}
    }
#endif

    /* tp.tv_sec is #secs since Jan 1, 1970 */
    pdt[0] = tp.tv_sec;

    /* Some Unix systems (e.g., Interactive 3.2 r3.0) return garbage */
    /* in tp.tv_usec.  Try to filter out the worst of it here. */
    pdt[1] = tp.tv_usec >= 0 && tp.tv_usec < 1000000 ? tp.tv_usec * 1000 : 0;

#ifdef DEBUG_CLOCK
    printf("tp.tv_sec = %d  tp.tv_usec = %d  pdt[0] = %ld  pdt[1] = %ld\n",
	   tp.tv_sec, tp.tv_usec, pdt[0], pdt[1]);
#endif
}

/* Read the current user CPU time (in seconds) */
/* and fraction (in nanoseconds).  */
void
gp_get_usertime(long *pdt)
{
#if use_times_for_usertime
    struct tms tms;
    long ticks;
    const long ticks_per_sec = CLK_TCK;

    times(&tms);
    ticks = tms.tms_utime + tms.tms_stime + tms.tms_cutime + tms.tms_cstime;
    pdt[0] = ticks / ticks_per_sec;
    pdt[1] = (ticks % ticks_per_sec) * (1000000000 / ticks_per_sec);
#else
    gp_get_realtime(pdt);	/* Use an approximation on other hosts.  */
#endif
}

/* ------ Screen management ------ */

/* Get the environment variable that specifies the display to use. */
const char *
gp_getenv_display(void)
{
    return getenv("DISPLAY");
}

/* ------ Printer accessing ------ */

/* Open a connection to a printer.  See gp.h for details. */
FILE *
gp_open_printer(char fname[gp_file_name_sizeof], int binary_mode)
{
    const char *fmode = (binary_mode ? "wb" : "w");

    return (strlen(fname) == 0 ? 0 : fopen(fname, fmode));
}

/* Close the connection to the printer. */
void
gp_close_printer(FILE * pfile, const char *fname)
{
    if (fname[0] == '|')
	pclose(pfile);
    else
	fclose(pfile);
}
