/*
	sys_linux.c

	(description)

	Copyright (C) 1996-1997  Id Software, Inc.

	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License
	as published by the Free Software Foundation; either version 2
	of the License, or (at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

	See the GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

	$Id$
*/

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <unistd.h>
#include <signal.h>
#include <stdlib.h>
#include <limits.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <string.h>
#include <ctype.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <errno.h>

#include "sys.h"
#include "quakedef.h"

int noconinput = 0;
int nostdout = 0;

char *basedir = ".";
char *cachedir = "/tmp";
qboolean is_server = false;

/* cvar_t  sys_linerefresh = {"sys_linerefresh","0"};// set for entity display
 CVAR_FIXME */
cvar_t  *sys_linerefresh;// set for entity display

// The translation table between the graphical font and plain ASCII  --KB
char qfont_table[256] =
{
	'\0', '#',  '#',  '#',  '#',  '.',  '#',  '#',
	'#',  9,    10,   '#',  ' ',  13,   '.',  '.',
	'[',  ']',  '0',  '1',  '2',  '3',  '4',  '5',
	'6',  '7',  '8',  '9',  '.',  '<',  '=',  '>',
	' ',  '!',  '"',  '#',  '$',  '%',  '&',  '\'',
	'(',  ')',  '*',  '+',  ',',  '-',  '.',  '/',
	'0',  '1',  '2',  '3',  '4',  '5',  '6',  '7',
	'8',  '9',  ':',  ';',  '<',  '=',  '>',  '?',
	'@',  'A',  'B',  'C',  'D',  'E',  'F',  'G',
	'H',  'I',  'J',  'K',  'L',  'M',  'N',  'O',
	'P',  'Q',  'R',  'S',  'T',  'U',  'V',  'W',
	'X',  'Y',  'Z',  '[',  '\\', ']',  '^',  '_',
	'`',  'a',  'b',  'c',  'd',  'e',  'f',  'g',
	'h',  'i',  'j',  'k',  'l',  'm',  'n',  'o',
	'p',  'q',  'r',  's',  't',  'u',  'v',  'w',
	'x',  'y',  'z',  '{',  '|',  '}',  '~',  '<',

	'<',  '=',  '>',  '#',  '#',  '.',  '#',  '#',
	'#',  '#',  ' ',  '#',  ' ',  '>',  '.',  '.',
	'[',  ']',  '0',  '1',  '2',  '3',  '4',  '5',
	'6',  '7',  '8',  '9',  '.',  '<',  '=',  '>',
	' ',  '!',  '"',  '#',  '$',  '%',  '&',  '\'',
	'(',  ')',  '*',  '+',  ',',  '-',  '.',  '/',
	'0',  '1',  '2',  '3',  '4',  '5',  '6',  '7',
	'8',  '9',  ':',  ';',  '<',  '=',  '>',  '?',
	'@',  'A',  'B',  'C',  'D',  'E',  'F',  'G',
	'H',  'I',  'J',  'K',  'L',  'M',  'N',  'O',
	'P',  'Q',  'R',  'S',  'T',  'U',  'V',  'W',
	'X',  'Y',  'Z',  '[',  '\\', ']',  '^',  '_',
	'`',  'a',  'b',  'c',  'd',  'e',  'f',  'g',
	'h',  'i',  'j',  'k',  'l',  'm',  'n',  'o', 
	'p',  'q',  'r',  's',  't',  'u',  'v',  'w',
	'x',  'y',  'z',  '{',  '|',  '}',  '~',  '<'
};


// =======================================================================
// General routines
// =======================================================================

void Sys_DebugNumber(int y, int val)
{
}

/*
void Sys_Printf (char *fmt, ...)
{
	va_list		argptr;
	char		text[1024];
	
	va_start (argptr,fmt);
	vsprintf (text,fmt,argptr);
	va_end (argptr);
	fprintf(stderr, "%s", text);
	
	Con_Print (text);
}

void Sys_Printf (char *fmt, ...)
{

    va_list     argptr;
    char        text[1024], *t_p;
    int         l, r;

    if (nostdout)
        return;

    va_start (argptr,fmt);
    vsprintf (text,fmt,argptr);
    va_end (argptr);

    l = strlen(text);
    t_p = text;

// make sure everything goes through, even though we are non-blocking
    while (l)
    {
        r = write (1, text, l);
        if (r != l)
            sleep (0);
        if (r > 0)
        {
            t_p += r;
            l -= r;
        }
    }

}
*/

void Sys_Printf (char *fmt, ...)
{
	va_list		argptr;
	char		text[2048];
	unsigned char		*p;

	va_start (argptr,fmt);
	vsnprintf (text, sizeof(text), fmt, argptr);
	va_end (argptr);

	if (nostdout)
		return;

	// translate to ASCII instead of printing [xx]  --KB
	for (p = (unsigned char *)text; *p; p++)
		putc(qfont_table[*p], stdout);
}

void Sys_Quit (void)
{
	Host_Shutdown();
    fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
	exit(0);
}

void Sys_Init(void)
{
#ifdef USE_INTEL_ASM
	Sys_SetFPCW();
#endif
}

void Sys_Error (char *error, ...)
{ 
    va_list     argptr;
    char        string[1024];

// change stdin to non blocking
    fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
    
    va_start (argptr, error);
    vsnprintf (string, sizeof(string), error, argptr);
    va_end (argptr);
	fprintf(stderr, "Error: %s\n", string);

	Host_Shutdown ();
	exit (1);

} 

void Sys_Warn (char *warning, ...)
{ 
    va_list     argptr;
    char        string[1024];
    
    va_start (argptr, warning);
    vsnprintf (string, sizeof(string), warning,argptr);
    va_end (argptr);
	fprintf(stderr, "Warning: %s", string);
} 

/*
============
Sys_FileTime

returns -1 if not present
============
*/
int	Sys_FileTime (char *path)
{
	struct	stat	buf;
	
	if (stat (path,&buf) == -1)
		return -1;
	
	return buf.st_mtime;
}


void Sys_mkdir (char *path)
{
    mkdir (path, 0777);
}

int Sys_FileOpenRead (char *path, int *handle)
{
	int	h;
	struct stat	fileinfo;
    
	
	h = open (path, O_RDONLY, 0666);
	*handle = h;
	if (h == -1)
		return -1;
	
	if (fstat (h,&fileinfo) == -1)
		Sys_Error ("Error fstating %s", path);

	return fileinfo.st_size;
}

int Sys_FileOpenWrite (char *path)
{
	int     handle;

	umask (0);
	
	handle = open(path,O_RDWR | O_CREAT | O_TRUNC
	, 0666);

	if (handle == -1)
		Sys_Error ("Error opening %s: %s", path,strerror(errno));

	return handle;
}

int Sys_FileWrite (int handle, void *src, int count)
{
	return write (handle, src, count);
}

void Sys_FileClose (int handle)
{
	close (handle);
}

void Sys_FileSeek (int handle, int position)
{
	lseek (handle, position, SEEK_SET);
}

int Sys_FileRead (int handle, void *dest, int count)
{
    return read (handle, dest, count);
}

void Sys_DebugLog(char *file, char *fmt, ...)
{
    va_list argptr; 
    static char data[1024];   // why static ?
    int fd;

    va_start (argptr, fmt);
    vsnprintf (data, sizeof(data), fmt, argptr);
    va_end(argptr);
//    fd = open(file, O_WRONLY | O_BINARY | O_CREAT | O_APPEND, 0666);
    fd = open(file, O_WRONLY | O_CREAT | O_APPEND, 0666);
    write(fd, data, strlen(data));
    close(fd);
}

void Sys_EditFile(char *filename)
{

	char cmd[256];
	char *term;
	char *editor;

	term = getenv("TERM");
	if (term && !strcmp(term, "xterm"))
	{
		editor = getenv("VISUAL");
		if (!editor)
			editor = getenv("EDITOR");
		if (!editor)
			editor = getenv("EDIT");
		if (!editor)
			editor = "vi";
		snprintf (cmd, sizeof(cmd), "xterm -e %s %s", editor, filename);
		system(cmd);
	}

}

double Sys_DoubleTime (void)
{
    struct timeval tp;
    struct timezone tzp; 
    static int      secbase; 
    
    gettimeofday(&tp, &tzp);  

    if (!secbase)
    {
        secbase = tp.tv_sec;
        return tp.tv_usec/1000000.0;
    }

    return (tp.tv_sec - secbase) + tp.tv_usec/1000000.0;
}

// =======================================================================
// Sleeps for microseconds
// =======================================================================

static volatile int oktogo;

void alarm_handler(int x)
{
	oktogo=1;
}

void Sys_LineRefresh(void)
{
}

void floating_point_exception_handler(int whatever)
{
//	Sys_Warn("floating point exception\n");
	signal(SIGFPE, floating_point_exception_handler);
}

char *Sys_ConsoleInput(void)
{
#if 0
    static char text[256];
    int     len;

	if (cls.state == ca_dedicated) {
		len = read (0, text, sizeof(text));
		if (len < 1)
			return NULL;
		text[len-1] = 0;    // rip off the /n and terminate

		return text;
	}
#endif
	return NULL;
}

#ifndef USE_INTEL_ASM
void Sys_HighFPPrecision (void)
{
}

void Sys_LowFPPrecision (void)
{
}
#endif

int		skipframes;

int main (int c, char **v)
{

	double		time, oldtime, newtime;
	quakeparms_t parms;
	int j;

//	static char cwd[1024];

//	signal(SIGFPE, floating_point_exception_handler);
	signal(SIGFPE, SIG_IGN);

	memset(&parms, 0, sizeof(parms));

	COM_InitArgv(c, v);
	parms.argc = com_argc;
	parms.argv = com_argv;

	parms.memsize = 16*1024*1024;

	j = COM_CheckParm("-mem");
	if (j)
		parms.memsize = (int) (Q_atof(com_argv[j+1]) * 1024 * 1024);
	parms.membase = malloc (parms.memsize);
	if (!parms.membase) {
		printf("Can't allocate memroy for zone.\n");
		return 1;
	}

	parms.basedir = basedir;
// caching is disabled by default, use -cachedir to enable
//	parms.cachedir = cachedir;

	noconinput = COM_CheckParm("-noconinput");
	if (!noconinput)
		fcntl(0, F_SETFL, fcntl (0, F_GETFL, 0) | FNDELAY);

	if (COM_CheckParm("-nostdout"))
		nostdout = 1;

	Sys_Init();

    Host_Init(&parms);

    oldtime = Sys_DoubleTime ();
    while (1)
    {
// find time spent rendering last frame
        newtime = Sys_DoubleTime ();
        time = newtime - oldtime;

		Host_Frame(time);
		oldtime = newtime;
    }

}


/*
================
Sys_MakeCodeWriteable
================
*/
void Sys_MakeCodeWriteable (unsigned long startaddr, unsigned long length)
{

	int r;
	unsigned long addr;
	int psize = getpagesize();

	addr = (startaddr & ~(psize-1)) - psize;

//	fprintf(stderr, "writable code %lx(%lx)-%lx, length=%lx\n", startaddr,
//			addr, startaddr+length, length);

	r = mprotect((char*)addr, length + startaddr - addr + psize, 7);

	if (r < 0)
    		Sys_Error("Protection change failed\n");

}