Consolidate the non-canonical epoch timers, like cpuid and Win32's

QueryPerformanceCounter, into an entropy source hres_timer. Its
results, if any, do not count as contributing entropy to the poll.

Convert the other (monotonic/fixed epoch) timers to a single function
get_nanoseconds_clock(), living in time.h, which statically chooses
the 'best' timer type (clock_gettime, gettimeofday, std::clock, in
that order depending on what is available). Add feature test macros
for clock_gettime and gettimeofday.

Remove the Timer class and timer.h. Remove the Timer& argument to the
algorithm benchmark function.

1 files changed, 87 insertions, 0 deletions

diff --git a/src/utils/time.cpp b/src/utils/time.cpp
new file mode 100644
index 000000000..856b1c7be
--- /dev/null
+++ b/src/utils/time.cpp
@@ -0,0 +1,87 @@
+/**
+* Time Functions
+* (C) 1999-2009 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/time.h>
+#include <botan/exceptn.h>
+#include <ctime>
+
+#if defined(BOTAN_TARGET_OS_HAS_GETTIMEOFDAY)
+  #include <sys/time.h>
+#endif
+
+#if defined(BOTAN_TARGET_OS_HAS_CLOCK_GETTIME)
+
+#ifndef _POSIX_C_SOURCE
+  #define _POSIX_C_SOURCE 199309
+#endif
+
+#include <time.h>
+
+#ifndef CLOCK_REALTIME
+  #define CLOCK_REALTIME 0
+#endif
+
+#endif
+
+namespace Botan {
+
+namespace {
+
+/**
+* Combine a two time values into a single one
+*/
+u64bit combine_timers(u32bit seconds, u32bit parts, u32bit parts_hz)
+   {
+   static const u64bit NANOSECONDS_UNITS = 1000000000;
+
+   u64bit res = seconds * NANOSECONDS_UNITS;
+   res += parts * (NANOSECONDS_UNITS / parts_hz);
+   return res;
+   }
+
+}
+
+/**
+* Get the system clock
+*/
+u64bit system_time()
+   {
+   return static_cast<u64bit>(std::time(0));
+   }
+
+/*
+* Convert a time_t to a struct tm
+*/
+std::tm time_t_to_tm(u64bit timer)
+   {
+   std::time_t time_val = static_cast<std::time_t>(timer);
+
+   std::tm* tm_p = std::gmtime(&time_val);
+   if (tm_p == 0)
+      throw Encoding_Error("time_t_to_tm could not convert");
+   return (*tm_p);
+   }
+
+u64bit get_nanoseconds_clock()
+   {
+#if defined(BOTAN_TARGET_OS_HAS_CLOCK_GETTIME)
+   struct ::timespec tv;
+   ::clock_gettime(CLOCK_REALTIME, &tv);
+   return combine_timers(tv.tv_sec, tv.tv_nsec, 1000000000);
+
+#elif defined(BOTAN_TARGET_OS_HAS_GETTIMEOFDAY)
+   struct ::timeval tv;
+   ::gettimeofday(&tv, 0);
+   return combine_timers(tv.tv_sec, tv.tv_usec, 1000000);
+
+#else
+   return combine_timers(std::time(0), std::clock(), CLOCKS_PER_SEC);
+
+#endif
+   }
+
+}