/* Copyright (C) 1989, 1995 Aladdin Enterprises.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin 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 Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin 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 Aladdin 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.
*/

/* gp_unix.c */
/* Unix-specific routines for Ghostscript */
#include "string_.h"
#include "gx.h"
#include "gsexit.h"
#include "gp.h"
#include "time_.h"

#if defined(SYSV) || defined(SVR4) || defined(CLK_TCK)
#include <sys/times.h>
#endif

/*
 * The following library routines aren't declared in any standard header.
 */
extern char *getenv(P1(const char *));
/*
 * Because of inconsistent (and sometimes incorrect) header files,
 * we must omit the argument list for popen.
 */
extern FILE *popen( /* P2(const char *, const char *) */ );
extern int pclose(P1(FILE *));
/*
 * 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.
 */
#ifdef __PROTOTYPES__
#  include <stdlib.h>		/* for exit */
#else
extern void exit(P1(int));
#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)
{	exit(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_clock(long *pdt)
{	struct timeval tp;

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

	static long ticks_per_sec;
	if ( !ticks_per_sec )		/* not initialized yet */
	  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_clock(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.  A null file name means use the */
/* standard printer connected to the machine, if any. */
/* "|command" opens an output pipe. */
/* Return NULL if the connection could not be opened. */
FILE *
gp_open_printer(char *fname, int binary_mode)
{	return
	  (strlen(fname) == 0 ?
	   gp_open_scratch_file(gp_scratch_file_name_prefix, fname, "w") :
	   fname[0] == '|' ?
	   popen(fname + 1, "w") :
	   fopen(fname, "w"));
}

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