Initial commit

sysfs/sysfs.go

@@ -0,0 +1,55 @@
+package sysfs
+
+import (
+	"io/ioutil"
+	"log"
+	"path/filepath"
+	"strings"
+)
+
+// DeviceByProperty lists the devices where a given property=value filters match.
+func DeviceByProperty(class string, filters ...string) []string {
+	files, err := filepath.Glob("/sys/class/" + class + "/*/uevent")
+	if err != nil {
+		log.Print("list devices failed: ", err)
+		return nil
+	}
+
+	filtered := make([]string, 0)
+
+filesLoop:
+	for _, file := range files {
+		ba, err := ioutil.ReadFile(file)
+		if err != nil {
+			log.Print("reading ", file, " failed: ", err)
+			continue
+		}
+
+		values := strings.Split(strings.TrimSpace(string(ba)), "\n")
+
+		devName := ""
+		for _, value := range values {
+			if strings.HasPrefix(value, "DEVNAME=") {
+				devName = value[len("DEVNAME="):]
+			}
+		}
+
+		for _, filter := range filters {
+			found := false
+			for _, value := range values {
+				if filter == value {
+					found = true
+					break
+				}
+			}
+
+			if !found {
+				continue filesLoop
+			}
+		}
+
+		filtered = append(filtered, devName)
+	}
+
+	return filtered
+}