sysinfo: standardize on PrintErrorAndDie for handling fatal errors

Signed-off-by: Sam James <sam@gentoo.org>

src/sysinfo.cc

@@ -478,25 +478,27 @@ int GetNumCPUs() {
 #ifdef BENCHMARK_HAS_SYSCTL
   int num_cpu = -1;
   if (GetSysctl("hw.ncpu", &num_cpu)) return num_cpu;
-  fprintf(stderr, "Err: %s\n", strerror(errno));
-  std::exit(EXIT_FAILURE);
+  PrintErrorAndDie("Err: ", strerror(errno));
 #elif defined(BENCHMARK_OS_WINDOWS)
   SYSTEM_INFO sysinfo;
   // Use memset as opposed to = {} to avoid GCC missing initializer false
   // positives.
   std::memset(&sysinfo, 0, sizeof(SYSTEM_INFO));
   GetSystemInfo(&sysinfo);
+  if (sysinfo.dwNumberOfProcessors <= 0) {
+    PrintErrorAndDie("Failed to identify number of processors");
+  }
   return sysinfo.dwNumberOfProcessors;  // number of logical
                                         // processors in the current
                                         // group
 #elif defined(BENCHMARK_OS_SOLARIS)
   // Returns -1 in case of a failure.
   long num_cpu = sysconf(_SC_NPROCESSORS_ONLN);
   if (num_cpu < 0) {
-    fprintf(stderr, "sysconf(_SC_NPROCESSORS_ONLN) failed with error: %s\n",
-            strerror(errno));
+    PrintErrorAndDie("sysconf(_SC_NPROCESSORS_ONLN) failed with error: ",
+                     strerror(errno));
   }
-  return (int)num_cpu;
+  return static_cast<int>(num_cpu);
 #elif defined(BENCHMARK_OS_QNX)
   return static_cast<int>(_syspage_ptr->num_cpu);
 #elif defined(BENCHMARK_OS_QURT)
@@ -667,13 +669,11 @@ double GetCPUCyclesPerSecond(CPUInfo::Scaling scaling) {
     return static_cast<double>(freq) * 1000.0;
   }
 
-  const double error_value = -1;
-  double bogo_clock = error_value;
+  double bogo_clock = -1;
 
   std::ifstream f("/proc/cpuinfo");
   if (!f.is_open()) {
-    std::cerr << "failed to open /proc/cpuinfo\n";
-    return error_value;
+    PrintErrorAndDie("Failed to open /proc/cpuinfo");
   }
 
   auto StartsWithKey = [](std::string const& Value, std::string const& Key) {
@@ -701,17 +701,15 @@ double GetCPUCyclesPerSecond(CPUInfo::Scaling scaling) {
     } else if (StartsWithKey(ln, "bogomips")) {
       if (!value.empty()) {
         bogo_clock = benchmark::stod(value) * 1000000.0;
-        if (bogo_clock < 0.0) bogo_clock = error_value;
+        if (bogo_clock < 0.0) bogo_clock = -1;
       }
     }
   }
   if (f.bad()) {
-    std::cerr << "Failure reading /proc/cpuinfo\n";
-    return error_value;
+    PrintErrorAndDie("Failure reading /proc/cpuinfo");
   }
   if (!f.eof()) {
-    std::cerr << "Failed to read to end of /proc/cpuinfo\n";
-    return error_value;
+    PrintErrorAndDie("Failed to read to end of /proc/cpuinfo");
   }
   f.close();
   // If we found the bogomips clock, but nothing better, we'll use it (but
@@ -756,29 +754,24 @@ double GetCPUCyclesPerSecond(CPUInfo::Scaling scaling) {
 #elif defined(BENCHMARK_OS_SOLARIS)
   kstat_ctl_t* kc = kstat_open();
   if (!kc) {
-    std::cerr << "failed to open /dev/kstat\n";
-    return -1;
+    PrintErrorAndDie("Failed to open /dev/kstat");
   }
   kstat_t* ksp = kstat_lookup(kc, const_cast<char*>("cpu_info"), -1,
                               const_cast<char*>("cpu_info0"));
   if (!ksp) {
-    std::cerr << "failed to lookup in /dev/kstat\n";
-    return -1;
+    PrintErrorAndDie("Failed to lookup in /dev/kstat");
   }
   if (kstat_read(kc, ksp, NULL) < 0) {
-    std::cerr << "failed to read from /dev/kstat\n";
-    return -1;
+    PrintErrorAndDie("Failed to read from /dev/kstat");
   }
   kstat_named_t* knp = (kstat_named_t*)kstat_data_lookup(
       ksp, const_cast<char*>("current_clock_Hz"));
   if (!knp) {
-    std::cerr << "failed to lookup data in /dev/kstat\n";
-    return -1;
+    PrintErrorAndDie("Failed to lookup data in /dev/kstat");
   }
   if (knp->data_type != KSTAT_DATA_UINT64) {
-    std::cerr << "current_clock_Hz is of unexpected data type: "
-              << knp->data_type << "\n";
-    return -1;
+    PrintErrorAndDie("Current_clock_Hz is of unexpected data type: ",
+                     knp->data_type);
   }
   double clock_hz = knp->value.ui64;
   kstat_close(kc);