added linux timing code to SDL client for more accurate r_speeds reports

(sys_usetimegettime and sys_useclockgettime apply, set both to 0 to use
SDL_GetTicks instead)
added support for sys_usenoclockbutbenchmark in SDL client

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@10011 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/sys_sdl.c b/sys_sdl.c
index 4a908537cce4c72f4c56ac3efae71c0481a0c43e..4b45b6de8e4a67c738523e39df90c1f9ab6c3ca6 100644 (file)
--- a/sys_sdl.c
+++ b/sys_sdl.c
@@ -7,12 +7,24 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <sys/time.h>
+#include <time.h>
 #endif
 
 #include <signal.h>
 
 #include <SDL.h>
 
+cvar_t sys_usenoclockbutbenchmark = {CVAR_SAVE, "sys_usenoclockbutbenchmark", "0", "don't use ANY real timing, and simulate a clock (for benchmarking); the game then runs as fast as possible. Run a QC mod with bots that does some stuff, then does a quit at the end, to benchmark a server. NEVER do this on a public server."};
+static unsigned long benchmark_time;
+
+#ifndef WIN32
+# ifndef MACOSX
+cvar_t sys_useclockgettime = {CVAR_SAVE, "sys_useclockgettime", "0", "use POSIX clock_gettime function (which has issues if the system clock speed is far off, as it can't get fixed by NTP) for timing rather than gettimeofday (which has issues if the system time is stepped by ntpdate, or apparently on some Xen installations)"};
+# endif
+cvar_t sys_usegettimeofday = {CVAR_SAVE, "sys_usegettimeofday", "0", "use gettimeofday (which has issues if the system time is stepped by ntpdate, or apparently on some Xen installations) which has microsecond precision rather than SDL_GetTicks (which has only millisecond precision)"};
+#endif
+
+
 // =======================================================================
 // General routines
 // =======================================================================
@@ -74,7 +86,36 @@ double Sys_DoubleTime (void)
        static int first = true;
        static double oldtime = 0.0, curtime = 0.0;
        double newtime;
-       newtime = (double) SDL_GetTicks() / 1000.0;
+       if(sys_usenoclockbutbenchmark.integer)
+       {
+               benchmark_time += 1;
+               return ((double) benchmark_time) / 1e6;
+       }
+       // use higher precision timers on some platforms
+#ifndef WIN32
+# ifndef MACOSX
+       if (sys_useclockgettime.integer)
+       {
+               struct timespec ts;
+#  ifdef SUNOS
+               clock_gettime(CLOCK_HIGHRES, &ts);
+#  else
+               clock_gettime(CLOCK_MONOTONIC, &ts);
+#  endif
+               newtime = (double) ts.tv_sec + ts.tv_nsec / 1000000000.0;
+       }
+       else if (sys_usegettimeofday.integer)
+# endif
+       {
+               struct timeval tp;
+               gettimeofday(&tp, NULL);
+               newtime = (double) tp.tv_sec + tp.tv_usec / 1000000.0;
+       }
+       else
+#endif
+       {
+               newtime = (double) SDL_GetTicks() / 1000.0;
+       }
 
 
        if (first)
@@ -162,6 +203,11 @@ char *Sys_ConsoleInput(void)
 
 void Sys_Sleep(int microseconds)
 {
+       if(sys_usenoclockbutbenchmark.integer)
+       {
+               benchmark_time += microseconds;
+               return;
+       }
        SDL_Delay(microseconds / 1000);
 }
 
@@ -200,6 +246,13 @@ void Sys_InitConsole (void)
 
 void Sys_Init_Commands (void)
 {
+       Cvar_RegisterVariable(&sys_usenoclockbutbenchmark);
+#ifndef WIN32
+# ifndef MACOSX
+       Cvar_RegisterVariable(&sys_useclockgettime);
+# endif
+       Cvar_RegisterVariable(&sys_usegettimeofday);
+#endif
 }
 
 int main (int argc, char *argv[])