fix to power display

app/app.go

@@ -2,6 +2,7 @@ package app
 
 import (
 	"finally-a-monolithic-linux-hw-monitor/app/cpu"
+	"finally-a-monolithic-linux-hw-monitor/app/cpu/proc"
 	"fmt"
 	"os"
 	"os/signal"
@@ -24,11 +25,18 @@ func Run() {
 		os.Exit(0)
 	}()
 
+	proc, err := proc.GetProc()
+
 	ticker := time.NewTicker(1 * time.Second)
 	defer ticker.Stop()
 	for {
 		console := &strings.Builder{}
-		cpu.RenderCPU(console)
+
+		if err != nil {
+			return
+		}
+
+		cpu.RenderCPU(console, &proc)
 
 		console.WriteString("\nPress Ctrl+C to exit.\033[K\n")
 		fmt.Print(console.String())

app/cpu/cpu.go

@@ -6,12 +6,7 @@ import (
 	"strings"
 )
 
-func RenderCPU(console *strings.Builder) {
+func RenderCPU(console *strings.Builder, proc *proc.Proc) {
-	proc, err := proc.GetProc()
-	if err != nil {
-		return
-	}
-
 	// Move cursor to top-left (0,0) without clearing full buffer (flicker-free)
 	console.WriteString("\033[H")
 	console.WriteString(fmt.Sprintf("=== %s ===\n", proc.Model()))
@@ -20,9 +15,9 @@ func RenderCPU(console *strings.Builder) {
 	RenderPowerSensors(console, proc)
 }
 
-func RenderTemperatureSensors(console *strings.Builder, proc proc.Proc) {
+func RenderTemperatureSensors(console *strings.Builder, proc *proc.Proc) {
 	temps, _ := proc.SensorReader.ReadTemperatureSensors()
-	console.WriteString("=== Temperature ===\n")
+	console.WriteString("--- Temperature ---\n")
 	for _, sensor := range temps {
 		tempC := sensor.TempC
 		tempF := (tempC * 9 / 5) + 32
@@ -31,8 +26,8 @@ func RenderTemperatureSensors(console *strings.Builder, proc proc.Proc) {
 	}
 }
 
-func RenderPowerSensors(console *strings.Builder, proc proc.Proc) {
+func RenderPowerSensors(console *strings.Builder, proc *proc.Proc) {
-	console.WriteString("=== Power ===\n")
+	console.WriteString("--- Power ---\n")
 	power, _ := proc.SensorReader.ReadPowerSensors()
 	for _, sensor := range power {
 		// \033[K clears from cursor to end of line (prevents lingering chars)

app/cpu/proc/proc.go

@@ -45,6 +45,10 @@ func GetProc() (Proc, error) {
 	proc.Info = map[string]string{}
 
 	scanner := bufio.NewScanner(procFile)
+	if scanner.Err() != nil {
+		return proc, scanner.Err()
+	}
+
 	for scanner.Scan() {
 		line := scanner.Text()
 		line = strings.ReplaceAll(line, "\t", "")

app/cpu/proc/vendor_amd.go

@@ -2,6 +2,7 @@ package proc
 
 import (
 	"fmt"
+	"math"
 	"os"
 	"path/filepath"
 	"strconv"
@@ -12,7 +13,7 @@ import (
 type AMDReader struct {
 	hwmonDir    string
 	driver      string
-	energyState map[string]EnergyState // tracks (path -> energy state) for energy*_input calculations
+	energyState map[string]EnergyState
 }
 
 type EnergyState struct {
@@ -21,10 +22,9 @@ type EnergyState struct {
 }
 
 func NewAMDReader() (*AMDReader, error) {
-	// Locate AMD k10temp or zenpower hwmon path
 	matches, err := filepath.Glob("/sys/class/hwmon/hwmon*")
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("glob hwmon failed: %w", err)
 	}
 
 	for _, dir := range matches {
@@ -37,6 +37,7 @@ func NewAMDReader() (*AMDReader, error) {
 			return &AMDReader{
 				hwmonDir:    dir,
 				driver:      drv,
+				energyState: make(map[string]EnergyState),
 			}, nil
 		}
 	}
@@ -50,7 +51,7 @@ func (r *AMDReader) ReadTemperatureSensors() ([]TempSensor, error) {
 		return nil, fmt.Errorf("no temperature inputs found in %s", r.hwmonDir)
 	}
 
-	temps := []TempSensor{}
+	temps := make([]TempSensor, 0, len(inputs))
 
 	for _, inputPath := range inputs {
 		valBytes, err := os.ReadFile(inputPath)
@@ -90,7 +91,7 @@ func (r *AMDReader) ReadPowerSensors() ([]PowerSensor, error) {
 }
 
 func (r *AMDReader) readHwmonPower() []PowerSensor {
-	var powerSensors []PowerSensor
+	powerSensors := []PowerSensor{}
 
 	getLabel := func(inputPath string) string {
 		labelPath := strings.TrimSuffix(inputPath, "_input") + "_label"
@@ -127,22 +128,23 @@ func (r *AMDReader) readHwmonPower() []PowerSensor {
 }
 
 func (r *AMDReader) readRaplPower() []PowerSensor {
-	var powerSensors []PowerSensor
+	powerSensors := []PowerSensor{}
 
-	// Match both top-level and nested RAPL zone directories
 	patterns := []string{
 		"/sys/class/powercap/intel-rapl*/energy_uj",
 		"/sys/class/powercap/intel-rapl/intel-rapl*/energy_uj",
 		"/sys/class/powercap/intel-rapl/intel-rapl*/*/energy_uj",
+		"/sys/class/powercap/intel-rapl:*/energy_uj",
+		"/sys/class/powercap/intel-rapl:*/*/energy_uj",
 	}
 
-	var energyInputs []string
+	energyInputs := []string{}
 	seen := make(map[string]bool)
 
 	for _, pattern := range patterns {
 		matches, _ := filepath.Glob(pattern)
+
 		for _, match := range matches {
-			// Resolve symlinks to get real sysfs path
 			realPath, err := filepath.EvalSymlinks(match)
 			if err != nil {
 				realPath = match
@@ -172,18 +174,18 @@ func (r *AMDReader) readRaplPower() []PowerSensor {
 
 func (r *AMDReader) calculateEnergyDelta(inputs []string, getLabel func(string) string, out *[]PowerSensor) {
 	now := time.Now()
+
 	if r.energyState == nil {
 		r.energyState = make(map[string]EnergyState)
 	}
 
-	for _, inputPath := range inputs {
+	for _, rawPath := range inputs {
-		// Canonicalize path to resolve symlinks and prevent map key duplication
+		key, err := filepath.EvalSymlinks(rawPath)
-		realPath, err := filepath.EvalSymlinks(inputPath)
 		if err != nil {
-			realPath = inputPath
+			key = filepath.Clean(rawPath)
 		}
 
-		valBytes, err := os.ReadFile(realPath)
+		valBytes, err := os.ReadFile(key)
 		if err != nil {
 			continue
 		}
@@ -193,26 +195,29 @@ func (r *AMDReader) calculateEnergyDelta(inputs []string, getLabel func(string)
 			continue
 		}
 
-		prevState, exists := r.energyState[realPath]
+		prevState, exists := r.energyState[key]
-		r.energyState[realPath] = EnergyState{
+
+		if !exists {
+			r.energyState[key] = EnergyState{
 				lastEnergy: microJoules,
 				lastTime:   now,
 			}
-
+			*out = append(*out, PowerSensor{
-		// Initial seed step: power delta requires two distinct reads
+				Name:  getLabel(key),
-		if !exists {
+				Watts: 0.0,
+			})
 			continue
 		}
 
 		timeDiff := now.Sub(prevState.lastTime).Seconds()
-		if timeDiff <= 0 {
+		if timeDiff < 0.05 {
 			continue
 		}
 
-		maxRange := uint64(1<<64 - 1)
+		maxRange := uint64(math.MaxUint64)
-		rangeBytes, err := os.ReadFile(filepath.Join(filepath.Dir(realPath), "max_energy_range_uj"))
+		rangeBytes, err := os.ReadFile(filepath.Join(filepath.Dir(key), "max_energy_range_uj"))
 		if err == nil {
-			if parsedMax, err := strconv.ParseUint(strings.TrimSpace(string(rangeBytes)), 10, 64); err == nil {
+			if parsedMax, err := strconv.ParseUint(strings.TrimSpace(string(rangeBytes)), 10, 64); err == nil && parsedMax > 0 {
 				maxRange = parsedMax
 			}
 		}
@@ -221,12 +226,18 @@ func (r *AMDReader) calculateEnergyDelta(inputs []string, getLabel func(string)
 		if microJoules >= prevState.lastEnergy {
 			energyDiff = microJoules - prevState.lastEnergy
 		} else {
-			energyDiff = maxRange - prevState.lastEnergy + microJoules
+			energyDiff = (maxRange - prevState.lastEnergy) + microJoules
 		}
 
 		watts := (float64(energyDiff) / 1_000_000.0) / timeDiff
+
+		r.energyState[key] = EnergyState{
+			lastEnergy: microJoules,
+			lastTime:   now,
+		}
+
 		*out = append(*out, PowerSensor{
-			Name:  getLabel(realPath),
+			Name:  getLabel(key),
 			Watts: watts,
 		})
 	}