Added missing libsw library

external/libsdf/libsw/hwclock.c

@@ -0,0 +1,91 @@
+#include <stdio.h>
+#include <string.h>
+#include "error.h"
+#include "hwclock.h"
+
+static double hwtick_val;
+#define two_to_32 4294967296.0
+
+static double hwclock_offset;
+
+#if defined(__x86_64__) && defined(__GNUC__)
+#define DEFAULT_MHZ 1200.e6
+static double
+mhz_from_proc(){
+  FILE *fp = fopen("/proc/cpuinfo", "r");
+  char line[512];
+
+  if( fp == NULL ){
+    Warning("Can't open /proc/cpuinfo\n");
+    return DEFAULT_MHZ;
+  }
+    
+  while( fgets(line, sizeof(line), fp) ){
+    char *m;
+    int nscan;
+    double mhz;
+    
+    if( (m = strstr(line, "cpu MHz")) ){
+      /* sscanf should match any amount of whitespace around the : */
+      nscan = sscanf(m, "cpu MHz : %lf\n", &mhz);
+      if( nscan == 1 ){
+	fclose(fp);
+	return mhz*1.0e6;
+      }else{
+	Warning("sscanf returns %d, on '%s' of /proc/cpuinfo mhz line failed\n", nscan, line);
+	fclose(fp);
+	return DEFAULT_MHZ;	/* let's just guess 200Mhz */
+      }
+    }
+  }
+  Warning("Did not find cpu MHz in /proc/cpuinfo\n");
+  fclose(fp);
+  return DEFAULT_MHZ;
+}
+#endif
+
+/* This doesn't belong here, but I can't be bothered to figure out where
+   it does belong! */
+double 
+hwclock(void)
+{
+#if defined(__x86_64__)
+    static int init = 1;
+    unsigned int counter[2];
+  
+    __asm__("rdtsc \n\t"
+      "movl %%eax,%0 \n\t"
+      "movl %%edx,%1 \n\t"
+      : "=m" (((unsigned *)counter)[0]), "=m" (((unsigned *)counter)[1])
+      :
+      : "eax" , "edx");
+
+    if (init) {
+	init = 0;
+	hwtick_val = 1.0/mhz_from_proc();
+	hwclock_offset = hwtick_val*((double)counter[1]*two_to_32 + (double)counter[0]);
+	return 0.0;
+    }
+    return(hwtick_val*((double)counter[1]*two_to_32 + (double)counter[0])-hwclock_offset);
+#else
+    {
+      struct timeval tp;
+      struct timezone tzp;
+
+      gettimeofday(&tp,&tzp);
+      return ( (double) tp.tv_sec + (double) tp.tv_usec * 1.e-6 );
+    }
+#endif
+}
+
+void
+zero_hwclock(void)
+{
+    hwclock_offset += hwclock();
+}
+
+double
+hwtick(void)
+{
+  return hwtick_val;
+}