[load][solaris] implement AvgWithContext

README.md

@@ -130,7 +130,7 @@ will provide useful information.
   - CacheSize
   - Flags (ex: "fpu vme de pse tsc msr pae mce cx8 ...")
   - Microcode
-- load/LoadAvg() (linux, freebsd)
+- load/Avg() (linux, freebsd, solaris)
   - Load1
   - Load5
   - Load15

load/load_solaris.go

@@ -4,11 +4,12 @@
 package load
 
 import (
+	"bufio"
+	"bytes"
 	"context"
 	"os/exec"
+	"strconv"
 	"strings"
-
-	"github.com/shirou/gopsutil/v3/internal/common"
 )
 
 func Avg() (*AvgStat, error) {
@@ -16,7 +17,45 @@ func Avg() (*AvgStat, error) {
 }
 
 func AvgWithContext(ctx context.Context) (*AvgStat, error) {
-	return nil, common.ErrNotImplementedError
+	kstat, err := exec.LookPath("kstat")
+	if err != nil {
+		return nil, err
+	}
+
+	out, err := invoke.CommandWithContext(ctx, kstat, "-p", "unix:0:system_misc:avenrun_*")
+	if err != nil {
+		return nil, err
+	}
+
+	avg := &AvgStat{}
+	scanner := bufio.NewScanner(bytes.NewReader(out))
+	for scanner.Scan() {
+		flds := strings.Fields(scanner.Text())
+		if len(flds) < 2 {
+			continue
+		}
+		var tgt *float64
+		switch {
+		case strings.HasSuffix(flds[0], ":avenrun_1min"):
+			tgt = &avg.Load1
+		case strings.HasSuffix(flds[0], ":avenrun_5min"):
+			tgt = &avg.Load5
+		case strings.HasSuffix(flds[0], ":avenrun_15min"):
+			tgt = &avg.Load15
+		default:
+			continue
+		}
+		v, err := strconv.ParseInt(flds[1], 10, 64)
+		if err != nil {
+			return nil, err
+		}
+		*tgt = float64(v) / (1 << 8)
+	}
+	if err = scanner.Err(); err != nil {
+		return nil, err
+	}
+
+	return avg, nil
 }
 
 func Misc() (*MiscStat, error) {