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

*/
// common.c -- misc functions used in client and server

#include <ctype.h>

#ifdef SERVERONLY 
#include "qwsvdef.h"
#else
#include "quakedef.h"
#endif

#define MAX_NUM_ARGVS 50
#define NUM_SAFE_ARGVS  6

usercmd_t nullcmd; // guarenteed to be zero

static char *largv[MAX_NUM_ARGVS + NUM_SAFE_ARGVS + 1];
static char *argvdummy = " ";

static char *safeargvs[NUM_SAFE_ARGVS] =
  {"-stdvid", "-nolan", "-nosound", "-nocdaudio", "-nojoy", "-nomouse"};

cvar_t  registered = {"registered","0"};

qboolean  com_modified; // set true if using non-id files

int   static_registered = 1;  // only for startup check, then set

qboolean    msg_suppress_1 = 0;

void COM_InitFilesystem (void);
void COM_Path_f (void);

#if defined(M68KASM) || defined(PPCASM)
extern short ShortSwap(short);
extern int LongSwap(int);
extern float FloatSwap(float);
#endif

// if a packfile directory differs from this, it is assumed to be hacked
#define PAK0_COUNT    339
#define PAK0_CRC    52883

qboolean    standard_quake = true, rogue, hipnotic;

char  gamedirfile[MAX_OSPATH];

// this graphic needs to be in the pak file to use registered features
unsigned short pop[] =
{
 0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000,0x0000
,0x0000,0x0000,0x6600,0x0000,0x0000,0x0000,0x6600,0x0000
,0x0000,0x0066,0x0000,0x0000,0x0000,0x0000,0x0067,0x0000
,0x0000,0x6665,0x0000,0x0000,0x0000,0x0000,0x0065,0x6600
,0x0063,0x6561,0x0000,0x0000,0x0000,0x0000,0x0061,0x6563
,0x0064,0x6561,0x0000,0x0000,0x0000,0x0000,0x0061,0x6564
,0x0064,0x6564,0x0000,0x6469,0x6969,0x6400,0x0064,0x6564
,0x0063,0x6568,0x6200,0x0064,0x6864,0x0000,0x6268,0x6563
,0x0000,0x6567,0x6963,0x0064,0x6764,0x0063,0x6967,0x6500
,0x0000,0x6266,0x6769,0x6a68,0x6768,0x6a69,0x6766,0x6200
,0x0000,0x0062,0x6566,0x6666,0x6666,0x6666,0x6562,0x0000
,0x0000,0x0000,0x0062,0x6364,0x6664,0x6362,0x0000,0x0000
,0x0000,0x0000,0x0000,0x0062,0x6662,0x0000,0x0000,0x0000
,0x0000,0x0000,0x0000,0x0061,0x6661,0x0000,0x0000,0x0000
,0x0000,0x0000,0x0000,0x0000,0x6500,0x0000,0x0000,0x0000
,0x0000,0x0000,0x0000,0x0000,0x6400,0x0000,0x0000,0x0000
};

/*


All of Quake's data access is through a hierchal file system, but the contents of the file system can be transparently merged from several sources.

The "base directory" is the path to the directory holding the quake.exe and all game directories.  The sys_* files pass this to host_init in quakeparms_t->basedir.  This can be overridden with the "-basedir" command line parm to allow code debugging in a different directory.  The base directory is
only used during filesystem initialization.

The "game directory" is the first tree on the search path and directory that all generated files (savegames, screenshots, demos, config files) will be saved to.  This can be overridden with the "-game" command line parameter.  The game directory can never be changed while quake is executing.  This is a precacution against having a malicious server instruct clients to write files over areas they shouldn't.

The "cache directory" is only used during development to save network bandwidth, especially over ISDN / T1 lines.  If there is a cache directory
specified, when a file is found by the normal search path, it will be mirrored
into the cache directory, then opened there.
  
*/

//============================================================================


// ClearLink is used for new headnodes
void ClearLink (link_t *l)
{
  l->prev = l->next = l;
}

void RemoveLink (link_t *l)
{
  l->next->prev = l->prev;
  l->prev->next = l->next;
}

void InsertLinkBefore (link_t *l, link_t *before)
{
  l->next = before;
  l->prev = before->prev;
  l->prev->next = l;
  l->next->prev = l;
}
void InsertLinkAfter (link_t *l, link_t *after)
{
  l->next = after->next;
  l->prev = after;
  l->prev->next = l;
  l->next->prev = l;
}

/*
============================================================================

          LIBRARY REPLACEMENT FUNCTIONS

============================================================================
*/

#if 0
void Q_memset (void *dest, int fill, int count)
{
  int   i;
  
  if ( (((long)dest | count) & 3) == 0)
  {
    count >>= 2;
    fill = fill | (fill<<8) | (fill<<16) | (fill<<24);
    for (i=0 ; i<count ; i++)
      ((int *)dest)[i] = fill;
  }
  else
    for (i=0 ; i<count ; i++)
      ((byte *)dest)[i] = fill;
}

void Q_memcpy (void *dest, void *src, int count)
{
  int   i;
  
  if (( ( (long)dest | (long)src | count) & 3) == 0 )
  {
    count>>=2;
    for (i=0 ; i<count ; i++)
      ((int *)dest)[i] = ((int *)src)[i];
  }
  else
    for (i=0 ; i<count ; i++)
      ((byte *)dest)[i] = ((byte *)src)[i];
}

int Q_memcmp (void *m1, void *m2, int count)
{
  while(count)
  {
    count--;
    if (((byte *)m1)[count] != ((byte *)m2)[count])
      return -1;
  }
  return 0;
}

void Q_strcpy (char *dest, char *src)
{
  while (*src)
  {
    *dest++ = *src++;
  }
  *dest++ = 0;
}

void Q_strncpy (char *dest, char *src, int count)
{
  while (*src && count--)
  {
    *dest++ = *src++;
  }
  if (count)
    *dest++ = 0;
}

int Q_strlen (char *str)
{
  int   count;
  
  count = 0;
  while (str[count])
    count++;

  return count;
}

char *Q_strrchr(char *s, char c)
{
    int len = Q_strlen(s);
    s += len;
    while (len--)
        if (*--s == c) return s;
    return 0;
}

void Q_strcat (char *dest, char *src)
{
  dest += Q_strlen(dest);
  Q_strcpy (dest, src);
}

int Q_strcmp (char *s1, char *s2)
{
  while (1)
  {
    if (*s1 != *s2)
      return -1;    // strings not equal  
    if (!*s1)
      return 0;   // strings are equal
    s1++;
    s2++;
  }
  
  return -1;
}

int Q_strncmp (char *s1, char *s2, int count)
{
  while (1)
  {
    if (!count--)
      return 0;
    if (*s1 != *s2)
      return -1;    // strings not equal  
    if (!*s1)
      return 0;   // strings are equal
    s1++;
    s2++;
  }
  
  return -1;
}

int Q_strncasecmp (char *s1, char *s2, int n)
{
  int   c1, c2;
  
  while (1)
  {
    c1 = *s1++;
    c2 = *s2++;

    if (!n--)
      return 0;   // strings are equal until end point
    
    if (c1 != c2)
    {
      if (c1 >= 'a' && c1 <= 'z')
        c1 -= ('a' - 'A');
      if (c2 >= 'a' && c2 <= 'z')
        c2 -= ('a' - 'A');
      if (c1 != c2)
        return -1;    // strings not equal
    }
    if (!c1)
      return 0;   // strings are equal
//    s1++;
//    s2++;
  }
  
  return -1;
}

int Q_strcasecmp (char *s1, char *s2)
{
  return Q_strncasecmp (s1, s2, 99999);
}

#endif

int Q_atoi (char *str)
{
  int   val;
  int   sign;
  int   c;
  
  if (*str == '-')
  {
    sign = -1;
    str++;
  }
  else
    sign = 1;
    
  val = 0;

//
// check for hex
//
  if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X') )
  {
    str += 2;
    while (1)
    {
      c = *str++;
      if (c >= '0' && c <= '9')
        val = (val<<4) + c - '0';
      else if (c >= 'a' && c <= 'f')
        val = (val<<4) + c - 'a' + 10;
      else if (c >= 'A' && c <= 'F')
        val = (val<<4) + c - 'A' + 10;
      else
        return val*sign;
    }
  }
  
//
// check for character
//
  if (str[0] == '\'')
  {
    return sign * str[1];
  }
  
//
// assume decimal
//
  while (1)
  {
    c = *str++;
    if (c <'0' || c > '9')
      return val*sign;
    val = val*10 + c - '0';
  }
  
  return 0;
}


float Q_atof (char *str)
{
  double  val;
  int   sign;
  int   c;
  int   decimal, total;
  
  if (*str == '-')
  {
    sign = -1;
    str++;
  }
  else
    sign = 1;
    
  val = 0;

//
// check for hex
//
  if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X') )
  {
    str += 2;
    while (1)
    {
      c = *str++;
      if (c >= '0' && c <= '9')
        val = (val*16) + c - '0';
      else if (c >= 'a' && c <= 'f')
        val = (val*16) + c - 'a' + 10;
      else if (c >= 'A' && c <= 'F')
        val = (val*16) + c - 'A' + 10;
      else
        return val*sign;
    }
  }
  
//
// check for character
//
  if (str[0] == '\'')
  {
    return sign * str[1];
  }
  
//
// assume decimal
//
  decimal = -1;
  total = 0;
  while (1)
  {
    c = *str++;
    if (c == '.')
    {
      decimal = total;
      continue;
    }
    if (c <'0' || c > '9')
      break;
    val = val*10 + c - '0';
    total++;
  }

  if (decimal == -1)
    return val*sign;
  while (total > decimal)
  {
    val /= 10;
    total--;
  }
  
  return val*sign;
}

/*
============================================================================

          BYTE ORDER FUNCTIONS

============================================================================
*/

qboolean  bigendien;

short (*BigShort) (short l);
short (*LittleShort) (short l);
int (*BigLong) (int l);
int (*LittleLong) (int l);
float (*BigFloat) (float l);
float (*LittleFloat) (float l);

#if !defined(M68KASM) && !defined(PPCASM)
short   ShortSwap (short l)
{
  byte    b1,b2;

  b1 = l&255;
  b2 = (l>>8)&255;

  return (b1<<8) + b2;
}

int    LongSwap (int l)
{
  byte    b1,b2,b3,b4;

  b1 = l&255;
  b2 = (l>>8)&255;
  b3 = (l>>16)&255;
  b4 = (l>>24)&255;

  return ((int)b1<<24) + ((int)b2<<16) + ((int)b3<<8) + b4;
}
#endif

short ShortNoSwap (short l)
{
  return l;
}

int LongNoSwap (int l)
{
  return l;
}

#if !defined(M68KASM) && !defined(PPCASM)
float FloatSwap (float f)
{
  union
  {
    float f;
    byte  b[4];
  } dat1, dat2;
  
  
  dat1.f = f;
  dat2.b[0] = dat1.b[3];
  dat2.b[1] = dat1.b[2];
  dat2.b[2] = dat1.b[1];
  dat2.b[3] = dat1.b[0];
  return dat2.f;
}
#endif

float FloatNoSwap (float f)
{
  return f;
}

/*
==============================================================================

      MESSAGE IO FUNCTIONS

Handles byte ordering and avoids alignment errors
==============================================================================
*/

//
// writing functions
//

void MSG_WriteChar (sizebuf_t *sb, int c)
{
  byte  *buf;
  
#ifdef PARANOID
  if (c < -128 || c > 127)
    Sys_Error ("MSG_WriteChar: range error");
#endif

  buf = SZ_GetSpace (sb, 1);
  buf[0] = c;
}

void MSG_WriteByte (sizebuf_t *sb, int c)
{
  byte  *buf;
  
#ifdef PARANOID
  if (c < 0 || c > 255)
    Sys_Error ("MSG_WriteByte: range error");
#endif

  buf = SZ_GetSpace (sb, 1);
  buf[0] = c;
}

void MSG_WriteShort (sizebuf_t *sb, int c)
{
  byte  *buf;
  
#ifdef PARANOID
  if (c < ((short)0x8000) || c > (short)0x7fff)
    Sys_Error ("MSG_WriteShort: range error");
#endif

  buf = SZ_GetSpace (sb, 2);
  buf[0] = c&0xff;
  buf[1] = c>>8;
}

void MSG_WriteLong (sizebuf_t *sb, int c)
{
  byte  *buf;
  
  buf = SZ_GetSpace (sb, 4);
  buf[0] = c&0xff;
  buf[1] = (c>>8)&0xff;
  buf[2] = (c>>16)&0xff;
  buf[3] = c>>24;
}

void MSG_WriteFloat (sizebuf_t *sb, float f)
{
  union
  {
    float f;
    int l;
  } dat;
  
  
  dat.f = f;
  dat.l = LittleLong (dat.l);
  
  SZ_Write (sb, &dat.l, 4);
}

void MSG_WriteString (sizebuf_t *sb, char *s)
{
  if (!s)
    SZ_Write (sb, "", 1);
  else
    SZ_Write (sb, s, Q_strlen(s)+1);
}

void MSG_WriteCoord (sizebuf_t *sb, float f)
{
  MSG_WriteShort (sb, (int)(f*8));
}

void MSG_WriteAngle (sizebuf_t *sb, float f)
{
  MSG_WriteByte (sb, (int)(f*256/360) & 255);
}

void MSG_WriteAngle16 (sizebuf_t *sb, float f)
{
  MSG_WriteShort (sb, (int)(f*65536/360) & 65535);
}

void MSG_WriteDeltaUsercmd (sizebuf_t *buf, usercmd_t *from, usercmd_t *cmd)
{
  int   bits;

//
// send the movement message
//
  bits = 0;
  if (cmd->angles[0] != from->angles[0])
    bits |= CM_ANGLE1;
  if (cmd->angles[1] != from->angles[1])
    bits |= CM_ANGLE2;
  if (cmd->angles[2] != from->angles[2])
    bits |= CM_ANGLE3;
  if (cmd->forwardmove != from->forwardmove)
    bits |= CM_FORWARD;
  if (cmd->sidemove != from->sidemove)
    bits |= CM_SIDE;
  if (cmd->upmove != from->upmove)
    bits |= CM_UP;
  if (cmd->buttons != from->buttons)
    bits |= CM_BUTTONS;
  if (cmd->impulse != from->impulse)
    bits |= CM_IMPULSE;

    MSG_WriteByte (buf, bits);

  if (bits & CM_ANGLE1)
    MSG_WriteAngle16 (buf, cmd->angles[0]);
  if (bits & CM_ANGLE2)
    MSG_WriteAngle16 (buf, cmd->angles[1]);
  if (bits & CM_ANGLE3)
    MSG_WriteAngle16 (buf, cmd->angles[2]);
  
  if (bits & CM_FORWARD)
    MSG_WriteShort (buf, cmd->forwardmove);
  if (bits & CM_SIDE)
      MSG_WriteShort (buf, cmd->sidemove);
  if (bits & CM_UP)
    MSG_WriteShort (buf, cmd->upmove);

  if (bits & CM_BUTTONS)
      MSG_WriteByte (buf, cmd->buttons);
  if (bits & CM_IMPULSE)
      MSG_WriteByte (buf, cmd->impulse);
  MSG_WriteByte (buf, cmd->msec);
}


//
// reading functions
//
int     msg_readcount;
qboolean  msg_badread;

void MSG_BeginReading (void)
{
  msg_readcount = 0;
  msg_badread = false;
}

int MSG_GetReadCount(void)
{
  return msg_readcount;
}

// returns -1 and sets msg_badread if no more characters are available
int MSG_ReadChar (void)
{
  int c;
  
  if (msg_readcount+1 > net_message.cursize)
  {
    msg_badread = true;
    return -1;
  }
    
  c = (signed char)net_message.data[msg_readcount];
  msg_readcount++;
  
  return c;
}

int MSG_ReadByte (void)
{
  int c;
  
  if (msg_readcount+1 > net_message.cursize)
  {
    msg_badread = true;
    return -1;
  }
    
  c = (unsigned char)net_message.data[msg_readcount];
  msg_readcount++;
  
  return c;
}

int MSG_ReadShort (void)
{
  int c;
  
  if (msg_readcount+2 > net_message.cursize)
  {
    msg_badread = true;
    return -1;
  }
    
  c = (short)(net_message.data[msg_readcount]
  + (net_message.data[msg_readcount+1]<<8));
  
  msg_readcount += 2;
  
  return c;
}

int MSG_ReadLong (void)
{
  int c;
  
  if (msg_readcount+4 > net_message.cursize)
  {
    msg_badread = true;
    return -1;
  }
    
  c = net_message.data[msg_readcount]
  + (net_message.data[msg_readcount+1]<<8)
  + (net_message.data[msg_readcount+2]<<16)
  + (net_message.data[msg_readcount+3]<<24);
  
  msg_readcount += 4;
  
  return c;
}

float MSG_ReadFloat (void)
{
  union
  {
    byte  b[4];
    float f;
    int l;
  } dat;
  
  dat.b[0] =  net_message.data[msg_readcount];
  dat.b[1] =  net_message.data[msg_readcount+1];
  dat.b[2] =  net_message.data[msg_readcount+2];
  dat.b[3] =  net_message.data[msg_readcount+3];
  msg_readcount += 4;
  
  dat.l = LittleLong (dat.l);

  return dat.f; 
}

char *MSG_ReadString (void)
{
  static char string[2048];
  int   l,c;
  
  l = 0;
  do
  {
    c = MSG_ReadChar ();
    if (c == -1 || c == 0)
      break;
    string[l] = c;
    l++;
  } while (l < sizeof(string)-1);
  
  string[l] = 0;
  
  return string;
}

char *MSG_ReadStringLine (void)
{
  static char string[2048];
  int   l,c;
  
  l = 0;
  do
  {
    c = MSG_ReadChar ();
    if (c == -1 || c == 0 || c == '\n')
      break;
    string[l] = c;
    l++;
  } while (l < sizeof(string)-1);
  
  string[l] = 0;
  
  return string;
}

float MSG_ReadCoord (void)
{
  return MSG_ReadShort() * (1.0/8);
}

float MSG_ReadAngle (void)
{
  return MSG_ReadChar() * (360.0/256);
}

float MSG_ReadAngle16 (void)
{
  return MSG_ReadShort() * (360.0/65536);
}

void MSG_ReadDeltaUsercmd (usercmd_t *from, usercmd_t *move)
{
  int bits;

  memcpy (move, from, sizeof(*move));

  bits = MSG_ReadByte ();
    
// read current angles
  if (bits & CM_ANGLE1)
    move->angles[0] = MSG_ReadAngle16 ();
  if (bits & CM_ANGLE2)
    move->angles[1] = MSG_ReadAngle16 ();
  if (bits & CM_ANGLE3)
    move->angles[2] = MSG_ReadAngle16 ();
    
// read movement
  if (bits & CM_FORWARD)
    move->forwardmove = MSG_ReadShort ();
  if (bits & CM_SIDE)
    move->sidemove = MSG_ReadShort ();
  if (bits & CM_UP)
    move->upmove = MSG_ReadShort ();
  
// read buttons
  if (bits & CM_BUTTONS)
    move->buttons = MSG_ReadByte ();

  if (bits & CM_IMPULSE)
    move->impulse = MSG_ReadByte ();

// read time to run command
  move->msec = MSG_ReadByte ();
}


//===========================================================================

void SZ_Clear (sizebuf_t *buf)
{
  buf->cursize = 0;
  buf->overflowed = false;
}

void *SZ_GetSpace (sizebuf_t *buf, int length)
{
  void  *data;
  
  if (buf->cursize + length > buf->maxsize)
  {
    if (!buf->allowoverflow)
      Sys_Error ("SZ_GetSpace: overflow without allowoverflow set (%d)", buf->maxsize);
    
    if (length > buf->maxsize)
      Sys_Error ("SZ_GetSpace: %i is > full buffer size", length);
      
    Sys_Printf ("SZ_GetSpace: overflow\n"); // because Con_Printf may be redirected
    SZ_Clear (buf); 
    buf->overflowed = true;
  }

  data = buf->data + buf->cursize;
  buf->cursize += length;
  
  return data;
}

void SZ_Write (sizebuf_t *buf, void *data, int length)
{
  Q_memcpy (SZ_GetSpace(buf,length),data,length);   
}

void SZ_Print (sizebuf_t *buf, char *data)
{
  int   len;
  
  len = Q_strlen(data)+1;

  if (!buf->cursize || buf->data[buf->cursize-1])
    Q_memcpy ((byte *)SZ_GetSpace(buf, len),data,len); // no trailing 0
  else
    Q_memcpy ((byte *)SZ_GetSpace(buf, len-1)-1,data,len); // write over trailing 0
}


//============================================================================


/*
============
COM_SkipPath
============
*/
char *COM_SkipPath (char *pathname)
{
  char  *last;
  
  last = pathname;
  while (*pathname)
  {
    if (*pathname=='/')
      last = pathname+1;
    pathname++;
  }
  return last;
}

/*
============
COM_StripExtension
============
*/
void COM_StripExtension (char *in, char *out)
{
  while (*in && *in != '.')
    *out++ = *in++;
  *out = 0;
}

/*
============
COM_FileExtension
============
*/
char *COM_FileExtension (char *in)
{
  static char exten[8];
  int   i;

  while (*in && *in != '.')
    in++;
  if (!*in)
    return "";
  in++;
  for (i=0 ; i<7 && *in ; i++,in++)
    exten[i] = *in;
  exten[i] = 0;
  return exten;
}

/*
============
COM_FileBase
============
*/
void COM_FileBase (char *in, char *out)
{
  char *s, *s2;
  
  s = in + strlen(in) - 1;
  
  while (s != in && *s != '.')
    s--;
  
  for (s2 = s ; *s2 && *s2 != '/' ; s2--)
  ;
  
  if (s-s2 < 2)
    strcpy (out,"?model?");
  else
  {
    s--;
    strncpy (out,s2+1, s-s2);
    out[s-s2] = 0;
  }
}


/*
==================
COM_DefaultExtension
==================
*/
void COM_DefaultExtension (char *path, char *extension)
{
  char    *src;
//
// if path doesn't have a .EXT, append extension
// (extension should include the .)
//
  src = path + strlen(path) - 1;

  while (*src != '/' && src != path)
  {
    if (*src == '.')
      return;                 // it has an extension
    src--;
  }

  strcat (path, extension);
}

//============================================================================

char    com_token[1024];
int   com_argc;
char  **com_argv;


/*
==============
COM_Parse

Parse a token out of a string
==============
*/
char *COM_Parse (char *data)
{
  int   c;
  int   len;
  
  len = 0;
  com_token[0] = 0;
  
  if (!data)
    return NULL;
    
// skip whitespace
skipwhite:
  while ( (c = *data) <= ' ')
  {
    if (c == 0)
      return NULL;      // end of file;
    data++;
  }
  
// skip // comments
  if (c=='/' && data[1] == '/')
  {
    while (*data && *data != '\n')
      data++;
    goto skipwhite;
  }
  

// handle quoted strings specially
  if (c == '\"')
  {
    data++;
    while (1)
    {
      c = *data++;
      if (c=='\"' || !c)
      {
        com_token[len] = 0;
        return data;
      }
      com_token[len] = c;
      len++;
    }
  }

// parse a regular word
  do
  {
    com_token[len] = c;
    data++;
    len++;
    c = *data;
  } while (c>32);
  
  com_token[len] = 0;
  return data;
}


/*
================
COM_CheckParm

Returns the position (1 to argc-1) in the program's argument list
where the given parameter apears, or 0 if not present
================
*/
int COM_CheckParm (char *parm)
{
  int   i;
  
  for (i=1 ; i<com_argc ; i++)
  {
    if (!com_argv[i])
      continue;   // NEXTSTEP sometimes clears appkit vars.
    if (!Q_strcmp (parm,com_argv[i]))
      return i;
  }
    
  return 0;
}

/*
================
COM_CheckRegistered

Looks for the pop.txt file and verifies it.
Sets the "registered" cvar.
Immediately exits out if an alternate game was attempted to be started without
being registered.
================
*/
void COM_CheckRegistered (void)
{
  FILE    *h;
  unsigned short  check[128];
  int     i;

  COM_FOpenFile("gfx/pop.lmp", &h);
  static_registered = 0;

  if (!h)
  {
    Con_Printf ("Playing shareware version.\n");
#ifndef SERVERONLY
// FIXME DEBUG -- only temporary
    if (com_modified)
      Sys_Error ("You must have the registered version to play QuakeWorld");
#endif
    return;
  }

  fread (check, 1, sizeof(check), h);
  fclose (h);
  
  for (i=0 ; i<128 ; i++)
    if (pop[i] != (unsigned short)BigShort (check[i]))
      Sys_Error ("Corrupted data file.");
  
  Cvar_Set ("registered", "1");
  static_registered = 1;
  Con_Printf ("Playing registered version.\n");
}



/*
================
COM_InitArgv
================
*/
void COM_InitArgv (int argc, char **argv)
{
  qboolean  safe;
  int     i;

  safe = false;

  for (com_argc=0 ; (com_argc<MAX_NUM_ARGVS) && (com_argc < argc) ;
     com_argc++)
  {
    largv[com_argc] = argv[com_argc];
    if (!Q_strcmp ("-safe", argv[com_argc]))
      safe = true;
  }

  if (safe)
  {
  // force all the safe-mode switches. Note that we reserved extra space in
  // case we need to add these, so we don't need an overflow check
    for (i=0 ; i<NUM_SAFE_ARGVS ; i++)
    {
      largv[com_argc] = safeargvs[i];
      com_argc++;
    }
  }

  largv[com_argc] = argvdummy;
  com_argv = largv;
}

/*
================
COM_AddParm

Adds the given string at the end of the current argument list
================
*/
void COM_AddParm (char *parm)
{
  largv[com_argc++] = parm;
}


/*
================
COM_Init
================
*/
void COM_Init (void)
{
  byte  swaptest[2] = {1,0};

// set the byte swapping variables in a portable manner 
  if ( *(short *)swaptest == 1)
  {
    bigendien = false;
    BigShort = ShortSwap;
    LittleShort = ShortNoSwap;
    BigLong = LongSwap;
    LittleLong = LongNoSwap;
    BigFloat = FloatSwap;
    LittleFloat = FloatNoSwap;
  }
  else
  {
    bigendien = true;
    BigShort = ShortNoSwap;
    LittleShort = ShortSwap;
    BigLong = LongNoSwap;
    LittleLong = LongSwap;
    BigFloat = FloatNoSwap;
    LittleFloat = FloatSwap;
  }

  Cvar_RegisterVariable (&registered);
  Cmd_AddCommand ("path", COM_Path_f);

  COM_InitFilesystem ();
  COM_CheckRegistered ();
}


/*
============
va

does a varargs printf into a temp buffer, so I don't need to have
varargs versions of all text functions.
FIXME: make this buffer size safe someday
============
*/
char  *va(char *format, ...)
{
  va_list   argptr;
  static char   string[1024];
  
  va_start (argptr, format);
  vsprintf (string, format,argptr);
  va_end (argptr);

  return string;  
}


/// just for debugging
int memsearch (byte *start, int count, int search)
{
  int   i;
  
  for (i=0 ; i<count ; i++)
    if (start[i] == search)
      return i;
  return -1;
}

/*
=============================================================================

QUAKE FILESYSTEM

=============================================================================
*/

int com_filesize;


//
// in memory
//

typedef struct
{
  char  name[MAX_QPATH];
  int   filepos, filelen;
} packfile_t;

typedef struct pack_s
{
  char  filename[MAX_OSPATH];
  FILE  *handle;
  int   numfiles;
  packfile_t  *files;
} pack_t;

//
// on disk
//
typedef struct
{
  char  name[56];
  int   filepos, filelen;
} dpackfile_t;

typedef struct
{
  char  id[4];
  int   dirofs;
  int   dirlen;
} dpackheader_t;

#define MAX_FILES_IN_PACK 2048

char  com_gamedir[MAX_OSPATH];
char  com_basedir[MAX_OSPATH];

typedef struct searchpath_s
{
  char  filename[MAX_OSPATH];
  pack_t  *pack;    // only one of filename / pack will be used
  struct searchpath_s *next;
} searchpath_t;

searchpath_t  *com_searchpaths;
searchpath_t  *com_base_searchpaths;  // without gamedirs

/*
================
COM_filelength
================
*/
int COM_filelength (FILE *f)
{
  int   pos;
  int   end;

  pos = ftell (f);
  fseek (f, 0, SEEK_END);
  end = ftell (f);
  fseek (f, pos, SEEK_SET);

  return end;
}

int COM_FileOpenRead (char *path, FILE **hndl)
{
  FILE  *f;

  f = fopen(path, "rb");
  if (!f)
  {
    *hndl = NULL;
    return -1;
  }
  *hndl = f;
  
  return COM_filelength(f);
}

/*
============
COM_Path_f

============
*/
void COM_Path_f (void)
{
  searchpath_t  *s;
  
  Con_Printf ("Current search path:\n");
  for (s=com_searchpaths ; s ; s=s->next)
  {
    if (s == com_base_searchpaths)
      Con_Printf ("----------\n");
    if (s->pack)
      Con_Printf ("%s (%i files)\n", s->pack->filename, s->pack->numfiles);
    else
      Con_Printf ("%s\n", s->filename);
  }
}

/*
============
COM_WriteFile

The filename will be prefixed by the current game directory
============
*/
void COM_WriteFile (char *filename, void *data, int len)
{
  FILE  *f;
  char  name[MAX_OSPATH];
  
  sprintf (name, "%s/%s", com_gamedir, filename);
  
  f = fopen (name, "wb");
  if (!f) {
    Sys_mkdir(com_gamedir);
    f = fopen (name, "wb");
    if (!f)
      Sys_Error ("Error opening %s", filename);
  }
  
  Sys_Printf ("COM_WriteFile: %s\n", name);
  fwrite (data, 1, len, f);
  fclose (f);
}


/*
============
COM_CreatePath

Only used for CopyFile and download
============
*/
void  COM_CreatePath (char *path)
{
  char  *ofs;
  
  for (ofs = path+1 ; *ofs ; ofs++)
  {
    if (*ofs == '/')
    { // create the directory
      *ofs = 0;
      Sys_mkdir (path);
      *ofs = '/';
    }
  }
}


/*
===========
COM_CopyFile

Copies a file over from the net to the local cache, creating any directories
needed.  This is for the convenience of developers using ISDN from home.
===========
*/
void COM_CopyFile (char *netpath, char *cachepath)
{
  FILE  *in, *out;
  int   remaining, count;
  char  buf[4096];
  
  remaining = COM_FileOpenRead (netpath, &in);    
  COM_CreatePath (cachepath); // create directories up to the cache file
  out = fopen(cachepath, "wb");
  if (!out)
    Sys_Error ("Error opening %s", cachepath);
  
  while (remaining)
  {
    if (remaining < sizeof(buf))
      count = remaining;
    else
      count = sizeof(buf);
    fread (buf, 1, count, in);
    fwrite (buf, 1, count, out);
    remaining -= count;
  }

  fclose (in);
  fclose (out);
}

/*
===========
COM_FindFile

Finds the file in the search path.
Sets com_filesize and one of handle or file
===========
*/
int file_from_pak; // global indicating file came from pack file ZOID

int COM_FOpenFile (char *filename, FILE **file)
{
  searchpath_t  *search;
  char    netpath[MAX_OSPATH];
  pack_t    *pak;
  int     i;
  int     findtime;

  file_from_pak = 0;
    
//
// search through the path, one element at a time
//
  for (search = com_searchpaths ; search ; search = search->next)
  {
  // is the element a pak file?
    if (search->pack)
    {
    // look through all the pak file elements
      pak = search->pack;
      for (i=0 ; i<pak->numfiles ; i++)
        if (!strcmp (pak->files[i].name, filename))
        { // found it!
          Sys_Printf ("PackFile: %s : %s\n",pak->filename, filename);
        // open a new file on the pakfile
          *file = fopen (pak->filename, "rb");
          if (!*file)
            Sys_Error ("Couldn't reopen %s", pak->filename);  
          fseek (*file, pak->files[i].filepos, SEEK_SET);
          com_filesize = pak->files[i].filelen;
          file_from_pak = 1;
          return com_filesize;
        }
    }
    else
    {   
  // check a file in the directory tree
      if (!static_registered)
      { // if not a registered version, don't ever go beyond base
        if ( strchr (filename, '/') || strchr (filename,'\\'))
          continue;
      }
      
      sprintf (netpath, "%s/%s",search->filename, filename);
      
      findtime = Sys_FileTime (netpath);
      if (findtime == -1)
        continue;
        
      Sys_Printf ("FindFile: %s\n",netpath);

      *file = fopen (netpath, "rb");
      return COM_filelength (*file);
    }
    
  }
  
  Sys_Printf ("FindFile: can't find %s\n", filename);
  
  *file = NULL;
  com_filesize = -1;
  return -1;
}

/*
============
COM_LoadFile

Filename are reletive to the quake directory.
Allways appends a 0 byte to the loaded data.
============
*/
cache_user_t *loadcache;
byte  *loadbuf;
int   loadsize;
byte *COM_LoadFile (char *path, int usehunk)
{
  FILE  *h;
  byte  *buf;
  char  base[32];
  int   len;

  buf = NULL; // quiet compiler warning

// look for it in the filesystem or pack files
  len = com_filesize = COM_FOpenFile (path, &h);
  if (!h)
    return NULL;
  
// extract the filename base name for hunk tag
  COM_FileBase (path, base);
  
  if (usehunk == 1)
    buf = Hunk_AllocName (len+1, base);
  else if (usehunk == 2)
    buf = Hunk_TempAlloc (len+1);
  else if (usehunk == 0)
    buf = Z_Malloc (len+1);
  else if (usehunk == 3)
    buf = Cache_Alloc (loadcache, len+1, base);
  else if (usehunk == 4)
  {
    if (len+1 > loadsize)
      buf = Hunk_TempAlloc (len+1);
    else
      buf = loadbuf;
  }
  else
    Sys_Error ("COM_LoadFile: bad usehunk");

  if (!buf)
    Sys_Error ("COM_LoadFile: not enough space for %s", path);
    
  ((byte *)buf)[len] = 0;
#ifndef SERVERONLY
  Draw_BeginDisc ();
#endif
  fread (buf, 1, len, h);
  fclose (h);
#ifndef SERVERONLY
  Draw_EndDisc ();
#endif

  return buf;
}

byte *COM_LoadHunkFile (char *path)
{
  return COM_LoadFile (path, 1);
}

byte *COM_LoadTempFile (char *path)
{
  return COM_LoadFile (path, 2);
}

void COM_LoadCacheFile (char *path, struct cache_user_s *cu)
{
  loadcache = cu;
  COM_LoadFile (path, 3);
}

// uses temp hunk if larger than bufsize
byte *COM_LoadStackFile (char *path, void *buffer, int bufsize)
{
  byte  *buf;
  
  loadbuf = (byte *)buffer;
  loadsize = bufsize;
  buf = COM_LoadFile (path, 4);
  
  return buf;
}

/*
=================
COM_LoadPackFile

Takes an explicit (not game tree related) path to a pak file.

Loads the header and directory, adding the files at the beginning
of the list so they override previous pack files.
=================
*/
pack_t *COM_LoadPackFile (char *packfile)
{
  dpackheader_t header;
  int       i;
  packfile_t    *newfiles;
  int       numpackfiles;
  pack_t      *pack;
  FILE      *packhandle;
  dpackfile_t   info[MAX_FILES_IN_PACK];
  unsigned short    crc;

  if (COM_FileOpenRead (packfile, &packhandle) == -1)
    return NULL;

  fread (&header, 1, sizeof(header), packhandle);
  if (header.id[0] != 'P' || header.id[1] != 'A'
  || header.id[2] != 'C' || header.id[3] != 'K')
    Sys_Error ("%s is not a packfile", packfile);
  header.dirofs = LittleLong (header.dirofs);
  header.dirlen = LittleLong (header.dirlen);

  numpackfiles = header.dirlen / sizeof(dpackfile_t);

  if (numpackfiles > MAX_FILES_IN_PACK)
    Sys_Error ("%s has %i files", packfile, numpackfiles);

  if (numpackfiles != PAK0_COUNT)
    com_modified = true;  // not the original file

  newfiles = Z_Malloc (numpackfiles * sizeof(packfile_t));

  fseek (packhandle, header.dirofs, SEEK_SET);
  fread (&info, 1, header.dirlen, packhandle);

// crc the directory to check for modifications
  crc = CRC_Block((byte *)info, header.dirlen);

//  CRC_Init (&crc);
//  for (i=0 ; i<header.dirlen ; i++)
//    CRC_ProcessByte (&crc, ((byte *)info)[i]);
  if (crc != PAK0_CRC)
    com_modified = true;

// parse the directory
  for (i=0 ; i<numpackfiles ; i++)
  {
    strcpy (newfiles[i].name, info[i].name);
    newfiles[i].filepos = LittleLong(info[i].filepos);
    newfiles[i].filelen = LittleLong(info[i].filelen);
  }

  pack = Z_Malloc (sizeof (pack_t));
  strcpy (pack->filename, packfile);
  pack->handle = packhandle;
  pack->numfiles = numpackfiles;
  pack->files = newfiles;
  
  Con_Printf ("Added packfile %s (%i files)\n", packfile, numpackfiles);
  return pack;
}


/*
================
COM_AddGameDirectory

Sets com_gamedir, adds the directory to the head of the path,
then loads and adds pak1.pak pak2.pak ... 
================
*/
void COM_AddGameDirectory (char *dir)
{
  int       i;
  searchpath_t  *search;
  pack_t      *pak;
  char      pakfile[MAX_OSPATH];
  char      *p;

  if ((p = strrchr(dir, '/')) != NULL)
    strcpy(gamedirfile, ++p);
#ifdef AMIGA
  else if ((p = strrchr(dir, ':')) != NULL)  /*phx*/
    strcpy(gamedirfile, ++p);
#endif
  else
    strcpy(gamedirfile, dir);  /*fixed, phx*/
  strcpy (com_gamedir, dir);

//
// add the directory to the search path
//
  search = Hunk_Alloc (sizeof(searchpath_t));
  strcpy (search->filename, dir);
  search->next = com_searchpaths;
  com_searchpaths = search;

//
// add any pak files in the format pak0.pak pak1.pak, ...
//
  for (i=0 ; ; i++)
  {
    sprintf (pakfile, "%s/pak%i.pak", dir, i);
    pak = COM_LoadPackFile (pakfile);
    if (!pak)
      break;
    search = Hunk_Alloc (sizeof(searchpath_t));
    search->pack = pak;
    search->next = com_searchpaths;
    com_searchpaths = search;   
  }

}

/*
================
COM_Gamedir

Sets the gamedir and path to a different directory.
================
*/
void COM_Gamedir (char *dir)
{
  searchpath_t  *search, *next;
  int       i;
  pack_t      *pak;
  char      pakfile[MAX_OSPATH];

  if (strstr(dir, "..") || strstr(dir, "/")
    || strstr(dir, "\\") || strstr(dir, ":") )
  {
    Con_Printf ("Gamedir should be a single filename, not a path\n");
    return;
  }

  if (!strcmp(gamedirfile, dir))
    return;   // still the same
  strcpy (gamedirfile, dir);

  //
  // free up any current game dir info
  //
  while (com_searchpaths != com_base_searchpaths)
  {
    if (com_searchpaths->pack)
    {
      fclose (com_searchpaths->pack->handle);
      Z_Free (com_searchpaths->pack->files);
      Z_Free (com_searchpaths->pack);
    }
    next = com_searchpaths->next;
    Z_Free (com_searchpaths);
    com_searchpaths = next;
  }

  //
  // flush all data, so it will be forced to reload
  //
  Cache_Flush ();

  if (!strcmp(dir,"id1") || !strcmp(dir, "qw"))
    return;

  sprintf (com_gamedir, "%s%s", com_basedir, dir);  /*phx*/

  //
  // add the directory to the search path
  //
  search = Z_Malloc (sizeof(searchpath_t));
  strcpy (search->filename, com_gamedir);
  search->next = com_searchpaths;
  com_searchpaths = search;

  //
  // add any pak files in the format pak0.pak pak1.pak, ...
  //
  for (i=0 ; ; i++)
  {
    sprintf (pakfile, "%s/pak%i.pak", com_gamedir, i);
    pak = COM_LoadPackFile (pakfile);
    if (!pak)
      break;
    search = Z_Malloc (sizeof(searchpath_t));
    search->pack = pak;
    search->next = com_searchpaths;
    com_searchpaths = search;   
  }
}

/*
================
COM_InitFilesystem
================
*/
void COM_InitFilesystem (void)
{
  int   i;

//
// -basedir <path>
// Overrides the system supplied base directory (under id1)
//
  i = COM_CheckParm ("-basedir");
  if (i && i < com_argc-1)
    strcpy (com_basedir, com_argv[i+1]);
  else
    strcpy (com_basedir, host_parms.basedir);

// (phx) Make sure that basedir path is terminated by '/' or ':'
  i = strlen(com_basedir);
  if (com_basedir[i-1]!='/' && com_basedir[i-1]!=':'
      && com_basedir[i-1]!='\\') {
    com_basedir[i] = '/';
    com_basedir[i+1] = 0;
  }

//
// start up with id1 by default
//
  COM_AddGameDirectory (va("%sid1", com_basedir) ); /*phx*/
  COM_AddGameDirectory (va("%sqw", com_basedir) ); /*phx*/

  // any set gamedirs will be freed up to here
  com_base_searchpaths = com_searchpaths;
}



/*
=====================================================================

  INFO STRINGS

=====================================================================
*/

/*
===============
Info_ValueForKey

Searches the string for the given
key and returns the associated value, or an empty string.
===============
*/
char *Info_ValueForKey (char *s, char *key)
{
  char  pkey[512];
  static  char value[4][512]; // use two buffers so compares
                // work without stomping on each other
  static  int valueindex;
  char  *o;
  
  valueindex = (valueindex + 1) % 4;
  if (*s == '\\')
    s++;
  while (1)
  {
    o = pkey;
    while (*s != '\\')
    {
      if (!*s)
        return "";
      *o++ = *s++;
    }
    *o = 0;
    s++;

    o = value[valueindex];

    while (*s != '\\' && *s)
    {
      if (!*s)
        return "";
      *o++ = *s++;
    }
    *o = 0;

    if (!strcmp (key, pkey) )
      return value[valueindex];

    if (!*s)
      return "";
    s++;
  }
}

void Info_RemoveKey (char *s, char *key)
{
  char  *start;
  char  pkey[512];
  char  value[512];
  char  *o;

  if (strstr (key, "\\"))
  {
    Con_Printf ("Can't use a key with a \\\n");
    return;
  }

  while (1)
  {
    start = s;
    if (*s == '\\')
      s++;
    o = pkey;
    while (*s != '\\')
    {
      if (!*s)
        return;
      *o++ = *s++;
    }
    *o = 0;
    s++;

    o = value;
    while (*s != '\\' && *s)
    {
      if (!*s)
        return;
      *o++ = *s++;
    }
    *o = 0;

    if (!strcmp (key, pkey) )
    {
      strcpy (start, s);  // remove this part
      return;
    }

    if (!*s)
      return;
  }

}

void Info_RemovePrefixedKeys (char *start, char prefix)
{
  char  *s;
  char  pkey[512];
  char  value[512];
  char  *o;

  s = start;

  while (1)
  {
    if (*s == '\\')
      s++;
    o = pkey;
    while (*s != '\\')
    {
      if (!*s)
        return;
      *o++ = *s++;
    }
    *o = 0;
    s++;

    o = value;
    while (*s != '\\' && *s)
    {
      if (!*s)
        return;
      *o++ = *s++;
    }
    *o = 0;

    if (pkey[0] == prefix)
    {
      Info_RemoveKey (start, pkey);
      s = start;
    }

    if (!*s)
      return;
  }

}


void Info_SetValueForStarKey (char *s, char *key, char *value, int maxsize)
{
  char  new[1024], *v;
  int   c;
#ifdef SERVERONLY
  extern cvar_t sv_highchars;
#endif

  if (strstr (key, "\\") || strstr (value, "\\") )
  {
    Con_Printf ("Can't use keys or values with a \\\n");
    return;
  }

  if (strstr (key, "\"") || strstr (value, "\"") )
  {
    Con_Printf ("Can't use keys or values with a \"\n");
    return;
  }

  if (strlen(key) > 63 || strlen(value) > 63)
  {
    Con_Printf ("Keys and values must be < 64 characters.\n");
    return;
  }

  // this next line is kinda trippy
  if (*(v = Info_ValueForKey(s, key))) {
    // key exists, make sure we have enough room for new value, if we don't,
    // don't change it!
    if (strlen(value) - strlen(v) + strlen(s) > maxsize) {
      Con_Printf ("Info string length exceeded\n");
      return;
    }
  }
  Info_RemoveKey (s, key);
  if (!value || !strlen(value))
    return;

  sprintf (new, "\\%s\\%s", key, value);

  if ((int)(strlen(new) + strlen(s)) > maxsize)
  {
    Con_Printf ("Info string length exceeded\n");
    return;
  }

  // only copy ascii values
  s += strlen(s);
  v = new;
  while (*v)
  {
    c = (unsigned char)*v++;
#ifndef SERVERONLY
    // client only allows highbits on name
    if (stricmp(key, "name") != 0) {
      c &= 127;
      if (c < 32 || c > 127)
        continue;
      // auto lowercase team
      if (stricmp(key, "team") == 0)
        c = tolower(c);
    }
#else
    if (!sv_highchars.value) {
      c &= 127;
      if (c < 32 || c > 127)
        continue;
    }
#endif
//    c &= 127;   // strip high bits
    if (c > 13) // && c < 127)
      *s++ = c;
  }
  *s = 0;
}

void Info_SetValueForKey (char *s, char *key, char *value, int maxsize)
{
  if (key[0] == '*')
  {
    Con_Printf ("Can't set * keys\n");
    return;
  }

  Info_SetValueForStarKey (s, key, value, maxsize);
}

void Info_Print (char *s)
{
  char  key[512];
  char  value[512];
  char  *o;
  int   l;

  if (*s == '\\')
    s++;
  while (*s)
  {
    o = key;
    while (*s && *s != '\\')
      *o++ = *s++;

    l = o - key;
    if (l < 20)
    {
      memset (o, ' ', 20-l);
      key[20] = 0;
    }
    else
      *o = 0;
    Con_Printf ("%s", key);

    if (!*s)
    {
      Con_Printf ("MISSING VALUE\n");
      return;
    }

    o = value;
    s++;
    while (*s && *s != '\\')
      *o++ = *s++;
    *o = 0;

    if (*s)
      s++;
    Con_Printf ("%s\n", value);
  }
}

static byte chktbl[1024 + 4] = {
0x78,0xd2,0x94,0xe3,0x41,0xec,0xd6,0xd5,0xcb,0xfc,0xdb,0x8a,0x4b,0xcc,0x85,0x01,
0x23,0xd2,0xe5,0xf2,0x29,0xa7,0x45,0x94,0x4a,0x62,0xe3,0xa5,0x6f,0x3f,0xe1,0x7a,
0x64,0xed,0x5c,0x99,0x29,0x87,0xa8,0x78,0x59,0x0d,0xaa,0x0f,0x25,0x0a,0x5c,0x58,
0xfb,0x00,0xa7,0xa8,0x8a,0x1d,0x86,0x80,0xc5,0x1f,0xd2,0x28,0x69,0x71,0x58,0xc3,
0x51,0x90,0xe1,0xf8,0x6a,0xf3,0x8f,0xb0,0x68,0xdf,0x95,0x40,0x5c,0xe4,0x24,0x6b,
0x29,0x19,0x71,0x3f,0x42,0x63,0x6c,0x48,0xe7,0xad,0xa8,0x4b,0x91,0x8f,0x42,0x36,
0x34,0xe7,0x32,0x55,0x59,0x2d,0x36,0x38,0x38,0x59,0x9b,0x08,0x16,0x4d,0x8d,0xf8,
0x0a,0xa4,0x52,0x01,0xbb,0x52,0xa9,0xfd,0x40,0x18,0x97,0x37,0xff,0xc9,0x82,0x27,
0xb2,0x64,0x60,0xce,0x00,0xd9,0x04,0xf0,0x9e,0x99,0xbd,0xce,0x8f,0x90,0x4a,0xdd,
0xe1,0xec,0x19,0x14,0xb1,0xfb,0xca,0x1e,0x98,0x0f,0xd4,0xcb,0x80,0xd6,0x05,0x63,
0xfd,0xa0,0x74,0xa6,0x86,0xf6,0x19,0x98,0x76,0x27,0x68,0xf7,0xe9,0x09,0x9a,0xf2,
0x2e,0x42,0xe1,0xbe,0x64,0x48,0x2a,0x74,0x30,0xbb,0x07,0xcc,0x1f,0xd4,0x91,0x9d,
0xac,0x55,0x53,0x25,0xb9,0x64,0xf7,0x58,0x4c,0x34,0x16,0xbc,0xf6,0x12,0x2b,0x65,
0x68,0x25,0x2e,0x29,0x1f,0xbb,0xb9,0xee,0x6d,0x0c,0x8e,0xbb,0xd2,0x5f,0x1d,0x8f,
0xc1,0x39,0xf9,0x8d,0xc0,0x39,0x75,0xcf,0x25,0x17,0xbe,0x96,0xaf,0x98,0x9f,0x5f,
0x65,0x15,0xc4,0x62,0xf8,0x55,0xfc,0xab,0x54,0xcf,0xdc,0x14,0x06,0xc8,0xfc,0x42,
0xd3,0xf0,0xad,0x10,0x08,0xcd,0xd4,0x11,0xbb,0xca,0x67,0xc6,0x48,0x5f,0x9d,0x59,
0xe3,0xe8,0x53,0x67,0x27,0x2d,0x34,0x9e,0x9e,0x24,0x29,0xdb,0x69,0x99,0x86,0xf9,
0x20,0xb5,0xbb,0x5b,0xb0,0xf9,0xc3,0x67,0xad,0x1c,0x9c,0xf7,0xcc,0xef,0xce,0x69,
0xe0,0x26,0x8f,0x79,0xbd,0xca,0x10,0x17,0xda,0xa9,0x88,0x57,0x9b,0x15,0x24,0xba,
0x84,0xd0,0xeb,0x4d,0x14,0xf5,0xfc,0xe6,0x51,0x6c,0x6f,0x64,0x6b,0x73,0xec,0x85,
0xf1,0x6f,0xe1,0x67,0x25,0x10,0x77,0x32,0x9e,0x85,0x6e,0x69,0xb1,0x83,0x00,0xe4,
0x13,0xa4,0x45,0x34,0x3b,0x40,0xff,0x41,0x82,0x89,0x79,0x57,0xfd,0xd2,0x8e,0xe8,
0xfc,0x1d,0x19,0x21,0x12,0x00,0xd7,0x66,0xe5,0xc7,0x10,0x1d,0xcb,0x75,0xe8,0xfa,
0xb6,0xee,0x7b,0x2f,0x1a,0x25,0x24,0xb9,0x9f,0x1d,0x78,0xfb,0x84,0xd0,0x17,0x05,
0x71,0xb3,0xc8,0x18,0xff,0x62,0xee,0xed,0x53,0xab,0x78,0xd3,0x65,0x2d,0xbb,0xc7,
0xc1,0xe7,0x70,0xa2,0x43,0x2c,0x7c,0xc7,0x16,0x04,0xd2,0x45,0xd5,0x6b,0x6c,0x7a,
0x5e,0xa1,0x50,0x2e,0x31,0x5b,0xcc,0xe8,0x65,0x8b,0x16,0x85,0xbf,0x82,0x83,0xfb,
0xde,0x9f,0x36,0x48,0x32,0x79,0xd6,0x9b,0xfb,0x52,0x45,0xbf,0x43,0xf7,0x0b,0x0b,
0x19,0x19,0x31,0xc3,0x85,0xec,0x1d,0x8c,0x20,0xf0,0x3a,0xfa,0x80,0x4d,0x2c,0x7d,
0xac,0x60,0x09,0xc0,0x40,0xee,0xb9,0xeb,0x13,0x5b,0xe8,0x2b,0xb1,0x20,0xf0,0xce,
0x4c,0xbd,0xc6,0x04,0x86,0x70,0xc6,0x33,0xc3,0x15,0x0f,0x65,0x19,0xfd,0xc2,0xd3,

// map checksum goes here
0x00,0x00,0x00,0x00
};

static byte chkbuf[16 + 60 + 4];

static unsigned last_mapchecksum = 0;

#if 0
/*
====================
COM_BlockSequenceCheckByte

For proxy protecting
====================
*/
byte  COM_BlockSequenceCheckByte (byte *base, int length, int sequence, unsigned mapchecksum)
{
  int   checksum;
  byte  *p;

  if (last_mapchecksum != mapchecksum) {
    last_mapchecksum = mapchecksum;
    chktbl[1024] = (mapchecksum & 0xff000000) >> 24;
    chktbl[1025] = (mapchecksum & 0x00ff0000) >> 16;
    chktbl[1026] = (mapchecksum & 0x0000ff00) >> 8;
    chktbl[1027] = (mapchecksum & 0x000000ff);

    Com_BlockFullChecksum (chktbl, sizeof(chktbl), chkbuf);
  }

  p = chktbl + (sequence % (sizeof(chktbl) - 8));

  if (length > 60)
    length = 60;
  memcpy (chkbuf + 16, base, length);

  length += 16;

  chkbuf[length] = (sequence & 0xff) ^ p[0];
  chkbuf[length+1] = p[1];
  chkbuf[length+2] = ((sequence>>8) & 0xff) ^ p[2];
  chkbuf[length+3] = p[3];

  length += 4;

  checksum = LittleLong(Com_BlockChecksum (chkbuf, length));

  checksum &= 0xff;

  return checksum;
}
#endif

/*
====================
COM_BlockSequenceCRCByte

For proxy protecting
====================
*/
byte  COM_BlockSequenceCRCByte (byte *base, int length, int sequence)
{
  unsigned short crc;
  byte  *p;
  byte chkb[60 + 4];

  p = chktbl + (sequence % (sizeof(chktbl) - 8));

  if (length > 60)
    length = 60;
  memcpy (chkb, base, length);

  chkb[length] = (sequence & 0xff) ^ p[0];
  chkb[length+1] = p[1];
  chkb[length+2] = ((sequence>>8) & 0xff) ^ p[2];
  chkb[length+3] = p[3];

  length += 4;

  crc = CRC_Block(chkb, length);

  crc &= 0xff;

  return crc;
}

// char *date = "Oct 24 1996";
static char *date = __DATE__ ;
static char *mon[12] = 
{ "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
static char mond[12] = 
{ 31,    28,    31,    30,    31,    30,    31,    31,    30,    31,    30,    31 };

// returns days since Oct 24 1996
int build_number( void )
{
  int m = 0; 
  int d = 0;
  int y = 0;
  static int b = 0;

  if (b != 0)
    return b;

  for (m = 0; m < 11; m++)
  {
    if (Q_strncasecmp( &date[0], mon[m], 3 ) == 0)
      break;
    d += mond[m];
  }

  d += atoi( &date[4] ) - 1;

  y = atoi( &date[7] ) - 1900;

  b = d + (int)((y - 1) * 365.25);

  if (((y % 4) == 0) && m > 1)
  {
    b += 1;
  }

  b -= 35778; // Dec 16 1998

  return b;
}