Fix printing of time

src/benchmark.cc

@@ -341,10 +341,9 @@ bool ConsoleReporter::ReportContext(const BenchmarkContextData& context) {
             << ((context.num_cpus > 1) ? "s" : "") << "\n";
 
   int remainder_ms;
-  char time_buf[32];
   std::cout << walltime::Print(walltime::Now(), "%Y/%m/%d-%H:%M:%S",
                                true,   // use local timezone
-                               time_buf, &remainder_ms) << "\n"; 
+                               &remainder_ms) << "\n"; 
 
   // Show details of CPU model, caches, TLBs etc.
 //  if (!context.cpu_info.empty())

src/walltime.cc

@@ -119,21 +119,22 @@ WallTime Now() {
   return now;
 }
 
-const char* Print(WallTime time, const char *format, bool local,
-                  char* storage, int *remainder_us) {
-    struct tm split;
-    double subsecond;
-    if (!SplitTimezone(time, local, &split, &subsecond)) {
-      snprintf(storage, sizeof(storage), "Invalid time: %f", time);
-    } else {
-      if (remainder_us != NULL) {
-        *remainder_us = static_cast<int>((subsecond * 1000000) + 0.5);
-        if (*remainder_us > 999999) *remainder_us = 999999;
-        if (*remainder_us < 0)      *remainder_us = 0;
-      }
-      strftime(storage, sizeof(storage), format, &split);
+std::string Print(WallTime time, const char *format, bool local,
+                  int *remainder_us) {
+  char storage[32];
+  struct tm split;
+  double subsecond;
+  if (!SplitTimezone(time, local, &split, &subsecond)) {
+    snprintf(storage, sizeof(storage), "Invalid time: %f", time);
+  } else {
+    if (remainder_us != NULL) {
+      *remainder_us = static_cast<int>((subsecond * 1000000) + 0.5);
+      if (*remainder_us > 999999) *remainder_us = 999999;
+      if (*remainder_us < 0)      *remainder_us = 0;
     }
-    return storage;
+    strftime(storage, sizeof(storage), format, &split);
+  }
+  return std::string(storage);
 }
 }  // end namespace walltime
 }  // end namespace benchmark

src/walltime.h

 #ifndef BENCHMARK_WALLTIME_H_
 #define BENCHMARK_WALLTIME_H_
 
+#include <string>
+
 namespace benchmark {
 typedef double WallTime;
 
@@ -10,11 +12,11 @@ WallTime Now();
 
 // GIVEN: walltime, generic format string (as understood by strftime),
 // a boolean flag specifying if the time is local or UTC (true=local).
-// RETURNS: the formatted string. ALSO RETURNS: the storage printbuffer
-// passed and the remaining number of microseconds (never printed in
-// the string since strftime does not understand it)
-const char* Print(WallTime time, const char *format, bool local,
-                  char* storage, int *remainder_us);
+// RETURNS: the formatted string. ALSO RETURNS: the remaining number of
+// microseconds (never printed in the string since strftime does not understand
+// it)
+std::string Print(WallTime time, const char *format, bool local,
+                  int *remainder_us);
 }  // end namespace walltime
 }  // end namespace benchmark