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 void Sys_Shutdown (void)
  25 {
  26 #ifndef WIN32
  27         fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
  28 #endif
  29         fflush(stdout);
  30 }
  31
  32 void Sys_Error (const char *error, ...)
  33 {
  34         va_list argptr;
  35         char string[1024];
  36
  37 // change stdin to non blocking
  38 #ifndef WIN32
  39         fcntl (0, F_SETFL, fcntl (0, F_GETFL, 0) & ~FNDELAY);
  40 #endif
  41
  42         va_start (argptr,error);
  43         vsnprintf (string, sizeof (string), error, argptr);
  44         va_end (argptr);
  45         fprintf(stderr, "Error: %s\n", string);
  46
  47         Host_Shutdown ();
  48         exit (1);
  49 }
  50
  51 void Sys_PrintToTerminal(const char *text)
  52 {
  53         printf("%s", text);
  54 }
  55
  56 double Sys_DoubleTime (void)
  57 {
  58         static int first = true;
  59         static double oldtime = 0.0, curtime = 0.0;
  60         double newtime;
  61 #ifdef WIN32
  62         // LordHavoc: note to people modifying this code, DWORD is specifically defined as an unsigned 32bit number, therefore the 65536.0 * 65536.0 is fine.
  63         if (sys_usetimegettime.integer)
  64         {
  65                 static int firsttimegettime = true;
  66                 // timeGetTime
  67                 // platform:
  68                 // Windows 95/98/ME/NT/2000/XP
  69                 // features:
  70                 // reasonable accuracy (millisecond)
  71                 // issues:
  72                 // wraps around every 47 days or so (but this is non-fatal to us, odd times are rejected, only causes a one frame stutter)
  73
  74                 // make sure the timer is high precision, otherwise different versions of windows have varying accuracy
  75                 if (firsttimegettime)
  76                 {
  77                         timeBeginPeriod (1);
  78                         firsttimegettime = false;
  79                 }
  80
  81                 newtime = (double) timeGetTime () / 1000.0;
  82         }
  83         else
  84         {
  85                 // QueryPerformanceCounter
  86                 // platform:
  87                 // Windows 95/98/ME/NT/2000/XP
  88                 // features:
  89                 // very accurate (CPU cycles)
  90                 // known issues:
  91                 // does not necessarily match realtime too well (tends to get faster and faster in win98)
  92                 // wraps around occasionally on some platforms (depends on CPU speed and probably other unknown factors)
  93                 double timescale;
  94                 LARGE_INTEGER PerformanceFreq;
  95                 LARGE_INTEGER PerformanceCount;
  96
  97                 if (!QueryPerformanceFrequency (&PerformanceFreq))
  98                         Sys_Error ("No hardware timer available");
  99                 QueryPerformanceCounter (&PerformanceCount);
 100
 101                 #ifdef __BORLANDC__
 102                 timescale = 1.0 / ((double) PerformanceFreq.u.LowPart + (double) PerformanceFreq.u.HighPart * 65536.0 * 65536.0);
 103                 newtime = ((double) PerformanceCount.u.LowPart + (double) PerformanceCount.u.HighPart * 65536.0 * 65536.0) * timescale;
 104                 #else
 105                 timescale = 1.0 / ((double) PerformanceFreq.LowPart + (double) PerformanceFreq.HighPart * 65536.0 * 65536.0);
 106                 newtime = ((double) PerformanceCount.LowPart + (double) PerformanceCount.HighPart * 65536.0 * 65536.0) * timescale;
 107                 #endif
 108         }
 109 #else
 110         struct timeval tp;
 111         gettimeofday(&tp, NULL);
 112         newtime = (double) tp.tv_sec + tp.tv_usec / 1000000.0;
 113 #endif
 114
 115         if (first)
 116         {
 117                 first = false;
 118                 oldtime = newtime;
 119         }
 120
 121         if (newtime < oldtime)
 122         {
 123                 // warn if it's significant
 124                 if (newtime - oldtime < -0.01)
 125                         Con_Printf("Sys_DoubleTime: time stepped backwards (went from %f to %f, difference %f)\n", oldtime, newtime, newtime - oldtime);
 126         }
 127         else
 128                 curtime += newtime - oldtime;
 129         oldtime = newtime;
 130
 131         return curtime;
 132 }
 133
 134 char *Sys_ConsoleInput(void)
 135 {
 136         if (cls.state == ca_dedicated)
 137         {
 138                 static char text[256];
 139                 static int len = 0;
 140 #ifdef WIN32
 141                 int c;
 142
 143                 // read a line out
 144                 while (_kbhit ())
 145                 {
 146                         c = _getch ();
 147                         if (c == '\r')
 148                         {
 149                                 text[len] = '\0';
 150                                 putch ('\n');
 151                                 len = 0;
 152                                 return text;
 153                         }
 154                         if (c == '\b')
 155                         {
 156                                 if (len)
 157                                 {
 158                                         putch (c);
 159                                         putch (' ');
 160                                         putch (c);
 161                                         len--;
 162                                 }
 163                                 continue;
 164                         }
 165                         if (len < sizeof (text) - 1)
 166                         {
 167                                 putch (c);
 168                                 text[len] = c;
 169                                 len++;
 170                         }
 171                 }
 172 #else
 173                 fd_set fdset;
 174                 struct timeval timeout;
 175                 FD_ZERO(&fdset);
 176                 FD_SET(0, &fdset); // stdin
 177                 timeout.tv_sec = 0;
 178                 timeout.tv_usec = 0;
 179                 if (select (1, &fdset, NULL, NULL, &timeout) != -1 && FD_ISSET(0, &fdset))
 180                 {
 181                         len = read (0, text, sizeof(text));
 182                         if (len >= 1)
 183                         {
 184                                 // rip off the \n and terminate
 185                                 text[len-1] = 0;
 186                                 return text;
 187                         }
 188                 }
 189 #endif
 190         }
 191         return NULL;
 192 }
 193
 194 void Sys_Sleep(int milliseconds)
 195 {
 196         if (milliseconds < 1)
 197                 milliseconds = 1;
 198 #ifdef WIN32
 199         Sleep(milliseconds);
 200 #else
 201         usleep(milliseconds * 1000);
 202 #endif
 203 }
 204
 205 char *Sys_GetClipboardData (void)
 206 {
 207         return NULL;
 208 }
 209
 210 int main (int argc, const char **argv)
 211 {
 212         double frameoldtime, framenewtime;
 213
 214         signal(SIGFPE, SIG_IGN);
 215
 216         com_argc = argc;
 217         com_argv = argv;
 218
 219 #ifndef WIN32
 220         fcntl(0, F_SETFL, fcntl (0, F_GETFL, 0) | FNDELAY);
 221 #endif
 222
 223         Sys_Shared_EarlyInit();
 224
 225         Host_Init();
 226
 227         Sys_Shared_LateInit();
 228
 229         frameoldtime = Sys_DoubleTime () - 0.1;
 230         while (1)
 231         {
 232                 // find time spent rendering last frame
 233                 framenewtime = Sys_DoubleTime ();
 234
 235                 Host_Frame (framenewtime - frameoldtime);
 236
 237                 frameoldtime = framenewtime;
 238         }
 239         return 0;
 240 }