Merge pull request #13767 from ethanavatar/master

libutil, libexpr: #10542 abstract over getrusage for getting cpuTime stat and implement windows version

src/libutil/unix/current-process.cc

@@ -0,0 +1,23 @@
+#include "nix/util/current-process.hh"
+#include "nix/util/error.hh"
+#include <cmath>
+
+#include <sys/resource.h>
+
+namespace nix {
+
+std::chrono::microseconds getCpuUserTime()
+{
+    struct rusage buf;
+
+    if (getrusage(RUSAGE_SELF, &buf) != 0) {
+        throw SysError("failed to get CPU time");
+    }
+
+    std::chrono::seconds seconds(buf.ru_utime.tv_sec);
+    std::chrono::microseconds microseconds(buf.ru_utime.tv_usec);
+
+    return seconds + microseconds;
+}
+
+} // namespace nix

src/libutil/unix/meson.build

@@ -49,6 +49,7 @@ config_unix_priv_h = configure_file(
 sources += config_unix_priv_h
 
 sources += files(
+  'current-process.cc',
   'environment-variables.cc',
   'file-descriptor.cc',
   'file-path.cc',