From 05416bf4214d4b485a277fd3337002289378c7f5 Mon Sep 17 00:00:00 2001
From: Lukas Heiligenbrunner <lukas.heiligenbrunner@gmail.com>
Date: Thu, 5 May 2022 09:56:08 +0000
Subject: [PATCH] SMART Temperature Readout

---
 main.go          | 18 ++++++++++++++++++
 smartdiskinfo.go | 35 ++++++++++++++++++++++++++++-------
 2 files changed, 46 insertions(+), 7 deletions(-)

diff --git a/main.go b/main.go
index bf94859..6ac15ab 100644
--- a/main.go
+++ b/main.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"flag"
 	"fmt"
 	"log"
 	"os"
@@ -41,7 +42,24 @@ func main() {
 		os.Exit(-1)
 	}
 
+	tmpptr := flag.Bool("temp", false, "get temperatures")
+
+	flag.Parse()
+
 	disks := getDisks()
+
+	if *tmpptr {
+		fmt.Println("printing temperatures")
+
+		for _, dev := range disks.Blockdevices {
+			path := fmt.Sprintf("/dev/%s", dev.Name)
+
+			max, min, temp := getTemp(path)
+			fmt.Printf("%s temp: %d°C (max: %d°C, min: %d°C)\n", path, temp, max, min)
+		}
+		return
+	}
+
 	fmt.Printf("Running smart check on %d disks.\n", len(disks.Blockdevices))
 	for _, blockdevice := range disks.Blockdevices {
 		path := fmt.Sprintf("/dev/%s", blockdevice.Name)
diff --git a/smartdiskinfo.go b/smartdiskinfo.go
index a1c84a3..5df8491 100644
--- a/smartdiskinfo.go
+++ b/smartdiskinfo.go
@@ -37,18 +37,18 @@ type Item struct {
 	} `json:"raw"`
 }
 
-func checkSmartAttributes(diskpath string, isSeagate bool, isHdd bool) {
+type RawAttr struct {
+	AtaSmartAttr struct {
+		Table []Item `json:"table"`
+	} `json:"ata_smart_attributes"`
+}
+
+func getSmartValues(diskpath string) *RawAttr {
 	rawsmart := execSystem("smartctl", "-A", "-json", diskpath)
 	if rawsmart == nil {
 		fmt.Println("error while getting smart info")
 	}
 
-	type RawAttr struct {
-		AtaSmartAttr struct {
-			Table []Item `json:"table"`
-		} `json:"ata_smart_attributes"`
-	}
-
 	var rawattr RawAttr
 
 	err := json.Unmarshal(rawsmart, &rawattr)
@@ -56,6 +56,27 @@ func checkSmartAttributes(diskpath string, isSeagate bool, isHdd bool) {
 	if err != nil {
 		fmt.Println(err)
 	}
+	return &rawattr
+}
+
+func getTemp(diskpath string) (uint32, uint32, uint32) {
+	rawattr := getSmartValues(diskpath)
+	temp := getItemValue(rawattr.AtaSmartAttr.Table, "Temperature_Celsius")
+
+	// temp value is storead as following:
+	// 		4bytes			  4bytes		   4bytes
+	// [----------------|----------------|---------------]
+	// 		max temp		 min temp		  curr temp
+
+	max := temp >> 32
+	min := (temp & 0xff00ff) >> 16
+	currtemp := temp & 0x0000ff
+
+	return uint32(max), uint32(min), uint32(currtemp)
+}
+
+func checkSmartAttributes(diskpath string, isSeagate bool, isHdd bool) {
+	rawattr := getSmartValues(diskpath)
 
 	rrerrrate := getItemValue(rawattr.AtaSmartAttr.Table, "Raw_Read_Error_Rate")
 	// seagate hdds have a special way to represent their error rates