feat add benchmark for system_time_bench

src/strings/base64_bench.cc

@@ -1,12 +1,42 @@
 #include <benchmark/benchmark.h>
 #include <sled/random.h>
 #include <sled/strings/base64.h>
+#include <sstream>
+
+static std::string
+RandomString(size_t length)
+{
+    static const char chars[] = "0123456789"
+                                "abcdefghijklmnopqrstuvwxyz"
+                                "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    std::stringstream ss;
+    sled::Random rand(1314);
+    while (length--) { ss << chars[rand.Rand(sizeof(chars))]; }
+    return ss.str();
+}
 
 static void
 Base64Encode(benchmark::State &state)
 {
-    std::string input = "hello world\n";
-    for (auto _ : state) { (void) sled::Base64::Encode(input); }
+    for (auto _ : state) {
+        state.PauseTiming();
+        std::string input = RandomString(state.range(0));
+        state.ResumeTiming();
+        (void) sled::Base64::Encode(input);
+    }
+}
+
+static void
+Base64Decode(benchmark::State &state)
+{
+    for (auto _ : state) {
+        state.PauseTiming();
+        std::string input = RandomString(state.range(0));
+        std::string base64_input = sled::Base64::Encode(input);
+        state.ResumeTiming();
+        (void) sled::Base64::Decode(base64_input);
+    }
 }
 
 BENCHMARK(Base64Encode)->RangeMultiplier(10)->Range(10, 1000000);
+BENCHMARK(Base64Decode)->RangeMultiplier(10)->Range(10, 1000000);

src/system_time_bench.cc

@@ -0,0 +1,10 @@
+#include <benchmark/benchmark.h>
+#include <sled/system_time.h>
+
+static void
+SystemTimeNanos(benchmark::State &state)
+{
+    for (auto _ : state) { (void) sled::SystemTimeNanos(); }
+}
+
+BENCHMARK(SystemTimeNanos);