sys_linux.c

   1
   2 #ifdef WIN32
   3 #include "conio.h"
   4 #else
   5 #include <unistd.h>
   6 #include <fcntl.h>
   7 #include <sys/time.h>
   8 #endif
   9
  10 #include <signal.h>
  11
  12 #include "quakedef.h"
  13
  14
  15 #ifdef WIN32
  16 cvar_t sys_usetimegettime = {CVAR_SAVE, "sys_usetimegettime", "1"};
  17 #endif
  18
  19
  20
  21 // =======================================================================
  22 // General routines
  23 // =======================================================================
  24
  25 void Sys_Quit (void)
  26 {
  27         Host_Shutdown();
  28 #ifndef WIN32
  29         fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
  30 #endif
  31         fflush(stdout);
  32         exit(0);
  33 }
  34
  35 void Sys_Error (const char *error, ...)
  36 {
  37         va_list argptr;
  38         char string[1024];
  39
  40 // change stdin to non blocking
  41 #ifndef WIN32
  42         fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
  43 #endif
  44
  45         va_start (argptr,error);
  46         vsprintf (string,error,argptr);
  47         va_end (argptr);
  48         fprintf(stderr, "Error: %s\n", string);
  49
  50         Host_Shutdown ();
  51         exit (1);
  52 }
  53
  54 void Sys_Print(const char *text)
  55 {
  56         printf("%s", text);
  57 }
  58
  59 double Sys_DoubleTime (void)
  60 {
  61         static int first = true;
  62         static double oldtime = 0.0, curtime = 0.0;
  63         double newtime;
  64 #ifdef WIN32
  65         // LordHavoc: note to people modifying this code, DWORD is specifically defined as an unsigned 32bit number, therefore the 65536.0 * 65536.0 is fine.
  66         if (sys_usetimegettime.integer)
  67         {
  68                 static int firsttimegettime = true;
  69                 // timeGetTime
  70                 // platform:
  71                 // Windows 95/98/ME/NT/2000/XP
  72                 // features:
  73                 // reasonable accuracy (millisecond)
  74                 // issues:
  75                 // wraps around every 47 days or so (but this is non-fatal to us, odd times are rejected, only causes a one frame stutter)
  76
  77                 // make sure the timer is high precision, otherwise different versions of windows have varying accuracy
  78                 if (firsttimegettime)
  79                 {
  80                         timeBeginPeriod (1);
  81                         firsttimegettime = false;
  82                 }
  83
  84                 newtime = (double) timeGetTime () / 1000.0;
  85         }
  86         else
  87         {
  88                 // QueryPerformanceCounter
  89                 // platform:
  90                 // Windows 95/98/ME/NT/2000/XP
  91                 // features:
  92                 // very accurate (CPU cycles)
  93                 // known issues:
  94                 // does not necessarily match realtime too well (tends to get faster and faster in win98)
  95                 // wraps around occasionally on some platforms (depends on CPU speed and probably other unknown factors)
  96                 double timescale;
  97                 LARGE_INTEGER PerformanceFreq;
  98                 LARGE_INTEGER PerformanceCount;
  99
 100                 if (!QueryPerformanceFrequency (&PerformanceFreq))
 101                         Sys_Error ("No hardware timer available");
 102                 QueryPerformanceCounter (&PerformanceCount);
 103
 104                 #ifdef __BORLANDC__
 105                 timescale = 1.0 / ((double) PerformanceFreq.u.LowPart + (double) PerformanceFreq.u.HighPart * 65536.0 * 65536.0);
 106                 newtime = ((double) PerformanceCount.u.LowPart + (double) PerformanceCount.u.HighPart * 65536.0 * 65536.0) * timescale;
 107                 #else
 108                 timescale = 1.0 / ((double) PerformanceFreq.LowPart + (double) PerformanceFreq.HighPart * 65536.0 * 65536.0);
 109                 newtime = ((double) PerformanceCount.LowPart + (double) PerformanceCount.HighPart * 65536.0 * 65536.0) * timescale;
 110                 #endif
 111         }
 112 #else
 113         struct timeval tp;
 114         gettimeofday(&tp, NULL);
 115         newtime = (double) tp.tv_sec + tp.tv_usec / 1000000.0;
 116 #endif
 117
 118         if (first)
 119         {
 120                 first = false;
 121                 oldtime = newtime;
 122         }
 123
 124         if (newtime < oldtime)
 125         {
 126                 // warn if it's significant
 127                 if (newtime - oldtime < -0.01)
 128                         Con_Printf("Sys_DoubleTime: time stepped backwards (went from %f to %f, difference %f)\n", oldtime, newtime, newtime - oldtime);
 129         }
 130         else
 131                 curtime += newtime - oldtime;
 132         oldtime = newtime;
 133
 134         return curtime;
 135 }
 136
 137 char *Sys_ConsoleInput(void)
 138 {
 139         if (cls.state == ca_dedicated)
 140         {
 141                 static char text[256];
 142                 int len = 0;
 143 #ifdef WIN32
 144                 int c;
 145
 146                 // read a line out
 147                 while (_kbhit ())
 148                 {
 149                         c = _getch ();
 150                         putch (c);
 151                         if (c == '\r')
 152                         {
 153                                 text[len] = 0;
 154                                 putch ('\n');
 155                                 len = 0;
 156                                 return text;
 157                         }
 158                         if (c == 8)
 159                         {
 160                                 if (len)
 161                                 {
 162                                         putch (' ');
 163                                         putch (c);
 164                                         len--;
 165                                         text[len] = 0;
 166                                 }
 167                                 continue;
 168                         }
 169                         text[len] = c;
 170                         len++;
 171                         text[len] = 0;
 172                         if (len == sizeof (text))
 173                                 len = 0;
 174                 }
 175 #else
 176                 fd_set fdset;
 177                 struct timeval timeout;
 178                 FD_ZERO(&fdset);
 179                 FD_SET(0, &fdset); // stdin
 180                 timeout.tv_sec = 0;
 181                 timeout.tv_usec = 0;
 182                 if (select (1, &fdset, NULL, NULL, &timeout) != -1 && FD_ISSET(0, &fdset))
 183                 {
 184                         len = read (0, text, sizeof(text));
 185                         if (len >= 1)
 186                         {
 187                                 // rip off the \n and terminate
 188                                 text[len-1] = 0;
 189                                 return text;
 190                         }
 191                 }
 192 #endif
 193         }
 194         return NULL;
 195 }
 196
 197 void Sys_Sleep(void)
 198 {
 199 #ifdef WIN32
 200         Sleep (1);
 201 #else
 202         usleep(1);
 203 #endif
 204 }
 205
 206 int main (int argc, const char **argv)
 207 {
 208         double frameoldtime, framenewtime;
 209
 210         signal(SIGFPE, SIG_IGN);
 211
 212         com_argc = argc;
 213         com_argv = argv;
 214
 215 #ifndef WIN32
 216         fcntl(0, F_SETFL, fcntl (0, F_GETFL, 0) | FNDELAY);
 217 #endif
 218
 219         Sys_Shared_EarlyInit();
 220
 221         Host_Init();
 222
 223         Sys_Shared_LateInit();
 224
 225         frameoldtime = Sys_DoubleTime () - 0.1;
 226         while (1)
 227         {
 228                 // find time spent rendering last frame
 229                 framenewtime = Sys_DoubleTime ();
 230
 231                 Host_Frame (framenewtime - frameoldtime);
 232
 233                 frameoldtime = framenewtime;
 234         }
 235         return 0;
 236 }