Initial delivery of metrics code (#81)

* Initial delivery of metrics code

* Fix build issues

* Fix build issue with go vet

vendor/github.com/prometheus/procfs/proc_stat_test.go

@@ -0,0 +1,123 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"os"
+	"testing"
+)
+
+func TestProcStat(t *testing.T) {
+	p, err := FS("fixtures").NewProc(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	s, err := p.NewStat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for _, test := range []struct {
+		name string
+		want int
+		have int
+	}{
+		{name: "pid", want: 26231, have: s.PID},
+		{name: "user time", want: 1677, have: int(s.UTime)},
+		{name: "system time", want: 44, have: int(s.STime)},
+		{name: "start time", want: 82375, have: int(s.Starttime)},
+		{name: "virtual memory size", want: 56274944, have: s.VSize},
+		{name: "resident set size", want: 1981, have: s.RSS},
+	} {
+		if test.want != test.have {
+			t.Errorf("want %s %d, have %d", test.name, test.want, test.have)
+		}
+	}
+}
+
+func TestProcStatComm(t *testing.T) {
+	s1, err := testProcStat(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want, have := "vim", s1.Comm; want != have {
+		t.Errorf("want comm %s, have %s", want, have)
+	}
+
+	s2, err := testProcStat(584)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want, have := "(a b ) ( c d) ", s2.Comm; want != have {
+		t.Errorf("want comm %s, have %s", want, have)
+	}
+}
+
+func TestProcStatVirtualMemory(t *testing.T) {
+	s, err := testProcStat(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if want, have := 56274944, s.VirtualMemory(); want != have {
+		t.Errorf("want virtual memory %d, have %d", want, have)
+	}
+}
+
+func TestProcStatResidentMemory(t *testing.T) {
+	s, err := testProcStat(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if want, have := 1981*os.Getpagesize(), s.ResidentMemory(); want != have {
+		t.Errorf("want resident memory %d, have %d", want, have)
+	}
+}
+
+func TestProcStatStartTime(t *testing.T) {
+	s, err := testProcStat(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	time, err := s.StartTime()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if want, have := 1418184099.75, time; want != have {
+		t.Errorf("want start time %f, have %f", want, have)
+	}
+}
+
+func TestProcStatCPUTime(t *testing.T) {
+	s, err := testProcStat(26231)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if want, have := 17.21, s.CPUTime(); want != have {
+		t.Errorf("want cpu time %f, have %f", want, have)
+	}
+}
+
+func testProcStat(pid int) (ProcStat, error) {
+	p, err := FS("fixtures").NewProc(pid)
+	if err != nil {
+		return ProcStat{}, err
+	}
+
+	return p.NewStat()
+}