refactor: move 'gettime_i64()' to testutil.h

Relocate the clock time getter to testutil.h to make it
easily reusable across tests. This will be useful for
the upcoming unit test framework.

Author: furszy

src/bench.h

@@ -12,27 +12,7 @@
 #include <stdio.h>
 #include <string.h>
 
-#if (defined(_MSC_VER) && _MSC_VER >= 1900)
-#  include <time.h>
-#else
-#  include <sys/time.h>
-#endif
-
-static int64_t gettime_i64(void) {
-#if (defined(_MSC_VER) && _MSC_VER >= 1900)
-    /* C11 way to get wallclock time */
-    struct timespec tv;
-    if (!timespec_get(&tv, TIME_UTC)) {
-        fputs("timespec_get failed!", stderr);
-        exit(EXIT_FAILURE);
-    }
-    return (int64_t)tv.tv_nsec / 1000 + (int64_t)tv.tv_sec * 1000000LL;
-#else
-    struct timeval tv;
-    gettimeofday(&tv, NULL);
-    return (int64_t)tv.tv_usec + (int64_t)tv.tv_sec * 1000000LL;
-#endif
-}
+#include "util.h"
 
 #define FP_EXP (6)
 #define FP_MULT (1000000LL)

src/util.h

@@ -45,6 +45,28 @@ static void print_buf_plain(const unsigned char *buf, size_t len) {
     printf("\n}\n");
 }
 
+#if (defined(_MSC_VER) && _MSC_VER >= 1900)
+#  include <time.h>
+#else
+#  include <sys/time.h>
+#endif
+
+static int64_t gettime_i64(void) {
+#if (defined(_MSC_VER) && _MSC_VER >= 1900)
+    /* C11 way to get wallclock time */
+    struct timespec tv;
+    if (!timespec_get(&tv, TIME_UTC)) {
+        fputs("timespec_get failed!", stderr);
+        exit(EXIT_FAILURE);
+    }
+    return (int64_t)tv.tv_nsec / 1000 + (int64_t)tv.tv_sec * 1000000LL;
+#else
+    struct timeval tv;
+    gettimeofday(&tv, NULL);
+    return (int64_t)tv.tv_usec + (int64_t)tv.tv_sec * 1000000LL;
+#endif
+}
+
 # if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
 #  if SECP256K1_GNUC_PREREQ(2,7)
 #   define SECP256K1_INLINE __inline__