Publish ITWorx Pulse source

internal/hostcollect/loadavg.go

@@ -0,0 +1,36 @@
+package hostcollect
+
+import (
+	"fmt"
+	"math"
+	"strings"
+
+	"github.com/itworx/pulse/internal/host"
+)
+
+// parseLoadAverage reads the three load figures from /proc/loadavg. The remaining
+// fields (runnable/total tasks and last PID) are deliberately ignored: the domain has
+// no place for them and a process count from a PID namespace would be misleading.
+func parseLoadAverage(data []byte) (host.RawLoad, error) {
+	fields := strings.Fields(string(data))
+	if len(fields) < 3 {
+		return host.RawLoad{}, errBadLoadAverage
+	}
+	values := [3]float64{}
+	for index := 0; index < 3; index++ {
+		value, ok := parseFloat(fields[index])
+		if !ok || value < 0 || math.IsNaN(value) || math.IsInf(value, 0) {
+			return host.RawLoad{}, errBadLoadAverage
+		}
+		values[index] = value
+	}
+	return host.RawLoad{One: values[0], Five: values[1], Fifteen: values[2]}, nil
+}
+
+func (c *Collector) loadAverage() (host.RawLoad, error) {
+	data, err := readLimited(c.procPath("loadavg"), maxProcessFileBytes)
+	if err != nil {
+		return host.RawLoad{}, fmt.Errorf("hostcollect: read loadavg: %w", err)
+	}
+	return parseLoadAverage(data)
+}