Allow reading data of any size through socket

services/agetty-tty1.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty --noclear tty1
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

services/agetty-tty2.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty tty2
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

services/agetty-tty3.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty tty3
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

services/agetty-tty4.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty tty4
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

services/agetty-tty5.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty tty5
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

services/agetty-tty6.esv

@@ -5,3 +5,4 @@ start_cmd: /usr/bin/setsid /sbin/agetty tty6
 exit_method: kill
 crash_on_safe_exit: false
 restart: always
+setpgid: false

src/ectl/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/json"
 	"flag"
 	"fmt"
@@ -57,7 +58,57 @@ func main() {
 		return
 	} else if flag.Args()[0] == "service" || flag.Args()[0] == "sv" {
 		if len(flag.Args()) <= 1 {
-			fmt.Println("Usage: ectl service <start/stop/enable/disable/status/list> [service]")
+			fmt.Println("Usage: ectl service <reload/start/stop/enable/disable/status/list> [service]")
+			return
+		}
+		if flag.Arg(1) == "reload" {
+			type ServiceCommandJsonStruct struct {
+				Command string `json:"command"`
+				Service string `json:"service"`
+			}
+			serviceCommandJson := ServiceCommandJsonStruct{
+				Command: flag.Arg(1),
+			}
+
+			// Encode struct to json string
+			jsonData, err := json.Marshal(serviceCommandJson)
+			if err != nil {
+				log.Fatalf("Could not encode JSON data! Error: %s\n", err)
+			}
+
+			_, err = conn.Write(jsonData)
+			if err != nil {
+				log.Fatalf("Could not write JSON data to socket! Error: %s\n", err)
+			}
+
+			// Read data from the connection.
+			data, err := readAllConn(conn)
+			if err != nil {
+				log.Fatalf("Could not read data from socket! Error: %s\n", err)
+				return
+			}
+
+			// Print json data if flag is set
+			if *printJson {
+				fmt.Println(string(data))
+				return
+			}
+
+			// Decoode JSON data
+			var returnedJsonData map[string]any
+			err = json.Unmarshal(data, &returnedJsonData)
+			if err != nil {
+				log.Fatalf("Could not decode JSON data from connection!")
+			}
+
+			if err, ok := returnedJsonData["error"]; ok {
+				log.Fatal(err)
+			} else if msg, ok := returnedJsonData["success"]; ok {
+				fmt.Println(msg)
+			} else {
+				log.Fatal("Connection returned empty string!")
+			}
+
 			return
 		} else if flag.Arg(1) == "start" || flag.Arg(1) == "stop" || flag.Arg(1) == "restart" {
 			// Ensure service name argument has been set
@@ -86,27 +137,22 @@ func main() {
 				log.Fatalf("Could not write JSON data to socket! Error: %s\n", err)
 			}
 
-			// Create a buffer for incoming data.
-			buf := make([]byte, 4096)
-
 			// Read data from the connection.
-			n, err := conn.Read(buf)
+			data, err := readAllConn(conn)
-			if err == io.EOF {
-				return
-			}
 			if err != nil {
+				log.Fatalf("Could not read data from socket! Error: %s\n", err)
 				return
 			}
 
 			// Print json data if flag is set
 			if *printJson {
-				fmt.Println(string(buf[:n]))
+				fmt.Println(string(data))
 				return
 			}
 
 			// Decoode JSON data
 			var returnedJsonData map[string]any
-			err = json.Unmarshal(buf[:n], &returnedJsonData)
+			err = json.Unmarshal(data, &returnedJsonData)
 			if err != nil {
 				log.Fatalf("Could not decode JSON data from connection!")
 			}
@@ -162,27 +208,22 @@ func main() {
 				log.Fatalf("Could not write JSON data to socket! Error: %s\n", err)
 			}
 
-			// Create a buffer for incoming data.
-			buf := make([]byte, 4096)
-
 			// Read data from the connection.
-			n, err := conn.Read(buf)
+			data, err := readAllConn(conn)
-			if err == io.EOF {
-				return
-			}
 			if err != nil {
+				log.Fatalf("Could not read data from socket! Error: %s\n", err)
 				return
 			}
 
 			// Print json data if flag is set
 			if *printJson {
-				fmt.Println(string(buf[:n]))
+				fmt.Println(string(data))
 				return
 			}
 
 			// Decoode JSON data
 			var returnedJsonData map[string]any
-			err = json.Unmarshal(buf[:n], &returnedJsonData)
+			err = json.Unmarshal(data, &returnedJsonData)
 			if err != nil {
 				log.Fatalf("Could not decode JSON data from connection!")
 			}
@@ -223,27 +264,22 @@ func main() {
 				log.Fatalf("Could not write JSON data to socket! Error: %s\n", err)
 			}
 
-			// Create a buffer for incoming data.
-			buf := make([]byte, 4096)
-
 			// Read data from the connection.
-			n, err := conn.Read(buf)
+			data, err := readAllConn(conn)
-			if err == io.EOF {
-				return
-			}
 			if err != nil {
+				log.Fatalf("Could not read data from socket! Error: %s\n", err)
 				return
 			}
 
 			// Print json data if flag is set
 			if *printJson {
-				fmt.Println(string(buf[:n]))
+				fmt.Println(string(data))
 				return
 			}
 
 			// Decoode JSON data
 			var returnedJsonData map[string]any
-			err = json.Unmarshal(buf[:n], &returnedJsonData)
+			err = json.Unmarshal(data, &returnedJsonData)
 			if err != nil {
 				log.Fatalf("Could not decode JSON data from connection!")
 			}
@@ -253,11 +289,13 @@ func main() {
 			}
 
 			serviceState := returnedJsonData["state"].(string)
+			serviceDescription := returnedJsonData["description"].(string)
 			serviceEnabled := returnedJsonData["is_enabled"].(bool)
 			serviceStage := int(returnedJsonData["stage"].(float64))
 			processID := int(returnedJsonData["process_id"].(float64))
 
 			fmt.Printf("Name: %s\n", flag.Arg(2))
+			fmt.Printf("Description: %s\n", serviceDescription)
 			fmt.Printf("State: %s\n", serviceState)
 			if serviceEnabled {
 				fmt.Printf("Enabled: %t (Stage %d)\n", serviceEnabled, serviceStage)
@@ -288,27 +326,22 @@ func main() {
 				log.Fatalf("Could not write JSON data to socket! Error: %s\n", err)
 			}
 
-			// Create a buffer for incoming data.
-			buf := make([]byte, 4096)
-
 			// Read data from the connection.
-			n, err := conn.Read(buf)
+			data, err := readAllConn(conn)
-			if err == io.EOF {
-				return
-			}
 			if err != nil {
+				log.Fatalf("Could not read data from socket! Error: %s\n", err)
 				return
 			}
 
 			// Print json data if flag is set
 			if *printJson {
-				fmt.Println(string(buf[:n]))
+				fmt.Println(string(data))
 				return
 			}
 
 			// Decoode JSON data
 			var returnedJsonData map[string]any
-			err = json.Unmarshal(buf[:n], &returnedJsonData)
+			err = json.Unmarshal(data, &returnedJsonData)
 			if err != nil {
 				log.Fatalf("Could not decode JSON data from connection!")
 			}
@@ -319,12 +352,14 @@ func main() {
 
 			for _, serviceMap := range returnedJsonData["services"].([]any) {
 				serviceName := serviceMap.(map[string]any)["name"].(string)
+				serviceDescription := serviceMap.(map[string]any)["description"].(string)
 				serviceState := serviceMap.(map[string]any)["state"].(string)
 				serviceEnabled := serviceMap.(map[string]any)["is_enabled"].(bool)
 				serviceStage := int(serviceMap.(map[string]any)["stage"].(float64))
 				processID := int(serviceMap.(map[string]any)["process_id"].(float64))
 
 				fmt.Printf("Name: %s\n", serviceName)
+				fmt.Printf("Description: %s\n", serviceDescription)
 				fmt.Printf("State: %s\n", serviceState)
 				if serviceEnabled {
 					fmt.Printf("Enabled: %t (Stage %d)\n", serviceEnabled, serviceStage)
@@ -374,3 +409,24 @@ func dialSocket() {
 		log.Fatalf("Failed to set write deadline! Error: %s\n", err)
 	}
 }
+
+func readAllConn(conn net.Conn) ([]byte, error) {
+	var buf bytes.Buffer
+
+	for {
+		dataChunk := make([]byte, 1024)
+
+		n, err := conn.Read(dataChunk)
+		if err != nil && err != io.EOF {
+			return nil, err
+		}
+
+		buf.Write(dataChunk[:n])
+
+		if n < 1024 {
+			break
+		}
+	}
+
+	return buf.Bytes(), nil
+}

src/enit/main.go

@@ -215,16 +215,12 @@ func waitZombieProcesses() {
 func catchSignals() {
 	sigc := make(chan os.Signal, 1)
 	signal.Notify(sigc, syscall.SIGUSR1, syscall.SIGTERM, syscall.SIGINT, syscall.SIGCHLD)
-	defer close(sigc)
-	defer signal.Stop(sigc)
 	for {
 		switch <-sigc {
 		case syscall.SIGUSR1:
-			close(sigc)
 			signal.Stop(sigc)
 			shutdownSystem()
 		case syscall.SIGTERM, syscall.SIGINT:
-			close(sigc)
 			signal.Stop(sigc)
 			rebootSystem()
 		case syscall.SIGCHLD:

src/esvm/main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"crypto/sha256"
 	"flag"
 	"fmt"
 	"io"
@@ -145,16 +146,18 @@ func Init() {
 			service := EnitService{
 				Name:             "",
 				Description:      "",
-				Dependencies:    make([]string, 0),
 				Type:             "",
 				StartCmd:         "",
 				ExitMethod:       "",
 				StopCmd:          "",
 				Restart:          "",
+				Setpgid:          true,
 				CrashOnSafeExit:  true,
+				LogOutput:        true,
+				Filepath:         path.Join(serviceConfigDir, "services", entry.Name()),
+				filepathChecksum: sha256.Sum256(bytes),
 				restartCount:     0,
 				stopChannel:      make(chan bool),
-				LogOutput:       true,
 				state:            EnitServiceUnloaded,
 			}
 			if err := yaml.Unmarshal(bytes, &service); err != nil {
@@ -195,7 +198,7 @@ func Init() {
 	}
 
 	// Read enabled services
-	ReadEnabledServices()
+	EnabledServices := ReadEnabledServices()
 
 	// Start enabled services
 	stages := slices.Collect(maps.Keys(EnabledServices))
@@ -213,7 +216,6 @@ func Init() {
 					continue
 				}
 
-				if len(service.GetUnmetDependencies()) == 0 {
 				err := service.StartService()
 				if err != nil {
 					logger.Printf("Error: could not start service (%s): %s", service.Name, err)
@@ -222,11 +224,20 @@ func Init() {
 			}
 		}
 	}
-	}
 
 	logger.Println("ESVM initialized successfully!")
 }
 
+func Reload() {
+	logger.Println("Reloading all ESVM services...")
+
+	for _, service := range Services {
+		service.ReloadService()
+	}
+
+	logger.Println("All ESVM services have been reloaded!")
+}
+
 func Destroy() {
 	logger.Println("Stopping all ESVM services...")
 

src/esvm/service.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"crypto/sha256"
 	"fmt"
 	"io"
 	"os"
@@ -39,7 +40,6 @@ var EnitServiceStateNames map[EnitServiceState]string = map[EnitServiceState]str
 type EnitService struct {
 	Name             string `yaml:"name"`
 	Description      string `yaml:"description,omitempty"`
-	Dependencies    []string `yaml:"dependencies,omitempty"`
 	Type             string `yaml:"type"`
 	StartCmd         string `yaml:"start_cmd"`
 	ExitMethod       string `yaml:"exit_method"`
@@ -47,36 +47,20 @@ type EnitService struct {
 	StopCmd          string `yaml:"stop_cmd,omitempty"`
 	Restart          string `yaml:"restart,omitempty"`
 	ReadyFd          int    `yaml:"ready_fd"`
+	Setpgid          bool   `yaml:"setpgid"`
 	LogOutput        bool   `yaml:"log_output,omitempty"`
+	Filepath         string
+	filepathChecksum [32]byte
 	state            EnitServiceState
 	processID        int
 	restartCount     int
 	stopChannel      chan bool
+	shouldReload     bool
 }
 
 var Services = make([]*EnitService, 0)
-var EnabledServices = make(map[int][]string)
 var startedServicesOrder = make([]string, 0)
 
-func (service *EnitService) GetUnmetDependencies() (missingDependencies []string) {
-	for _, dependency := range service.Dependencies {
-		if strings.HasPrefix(dependency, "/") {
-			// File dependency
-			if _, err := os.Stat(dependency); err != nil {
-				missingDependencies = append(missingDependencies, dependency)
-			}
-		} else {
-			// Service dependency
-			depService := GetServiceByName(dependency)
-			if depService == nil {
-				missingDependencies = append(missingDependencies, dependency)
-			}
-		}
-	}
-
-	return missingDependencies
-}
-
 func (service *EnitService) GetProcess() *os.Process {
 	process, _ := os.FindProcess(service.processID)
 
@@ -117,6 +101,90 @@ func (service *EnitService) GetLogFile() (file *os.File, err error) {
 	return file, nil
 }
 
+func (service *EnitService) ReloadService() {
+	bytes, err := os.ReadFile(service.Filepath)
+	checksum := sha256.Sum256(bytes)
+	if slices.Equal(checksum[:], service.filepathChecksum[:]) {
+		return
+	}
+
+	if service.state == EnitServiceStarting || service.state == EnitServiceRunning {
+		service.shouldReload = true
+		logger.Printf("Warning: Service (%s) is currently running and will be reloaded when stopped\n", service.Name)
+		return
+	}
+	service.shouldReload = false
+
+	logger.Printf("Reloading service (%s)...\n", service.Filepath)
+
+	if os.IsNotExist(err) {
+		Services = slices.DeleteFunc(Services, func(sv *EnitService) bool {
+			return sv == service
+		})
+		logger.Printf("Service (%s) has been removed\n", service.Name)
+		return
+	} else if err != nil {
+		logger.Printf("Error: Could not read service file (%s)", service.Filepath)
+		return
+	}
+
+	newService := EnitService{
+		Name:             "",
+		Description:      "",
+		Type:             "",
+		StartCmd:         "",
+		ExitMethod:       "",
+		StopCmd:          "",
+		Restart:          "",
+		Setpgid:          true,
+		CrashOnSafeExit:  true,
+		LogOutput:        true,
+		Filepath:         service.Filepath,
+		filepathChecksum: checksum,
+		restartCount:     service.restartCount,
+		stopChannel:      service.stopChannel,
+		state:            service.state,
+	}
+	if err := yaml.Unmarshal(bytes, &newService); err != nil {
+		logger.Printf("Error: could not read service file %s", service.Filepath)
+		return
+	}
+
+	for _, sv := range Services {
+		if sv.Name == newService.Name && sv != service {
+			logger.Printf("Error: service with name (%s) has already been initialized", service.Name)
+		}
+	}
+
+	switch newService.Type {
+	case "simple", "background":
+	default:
+		logger.Printf("Error: unknown service type (%s)", newService.Type)
+		return
+	}
+
+	switch newService.ExitMethod {
+	case "stop_command", "kill":
+	default:
+		logger.Printf("Error: unknown exit method (%s)\n", newService.ExitMethod)
+		return
+	}
+
+	switch newService.Restart {
+	case "true", "always":
+	default:
+		newService.Restart = "false"
+	}
+
+	for i, sv := range Services {
+		if sv == service {
+			Services[i] = &newService
+		}
+	}
+
+	logger.Printf("Service (%s) has been reloaded!\n", newService.Name)
+}
+
 func (service *EnitService) StartService() (err error) {
 	if service == nil {
 		return nil
@@ -137,6 +205,7 @@ func (service *EnitService) StartService() (err error) {
 	}
 
 	cmd := exec.Command("/bin/sh", "-c", "exec "+service.StartCmd)
+	cmd.SysProcAttr = &syscall.SysProcAttr{Setpgid: service.Setpgid, Pgid: 0}
 	if logFile != nil {
 		cmd.Stdout = logFile
 		cmd.Stderr = logFile
@@ -190,8 +259,8 @@ func (service *EnitService) StartService() (err error) {
 				logFile.Close()
 			}
 
-			// Kill process
+			// Kill process and children
-			cmd.Process.Kill()
+			syscall.Kill(-service.processID, syscall.SIGKILL)
 
 			service.processID = 0
 			service.state = EnitServiceCrashed
@@ -214,10 +283,21 @@ func (service *EnitService) StartService() (err error) {
 		case <-service.stopChannel:
 			service.restartCount = 0
 		default:
+			// Kill remaining child processes
+			syscall.Kill(-service.processID, syscall.SIGKILL)
+
 			if service.Type == "simple" && err == nil {
 				service.restartCount = 0
 				if service.ExitMethod != "stop_command" {
 					service.state = EnitServiceCompleted
+
+					// Reload service if needed
+					if service.shouldReload {
+						service.ReloadService()
+						if GetServiceByName(service.Name) == nil {
+							return
+						}
+					}
 				} else {
 					service.state = EnitServiceRunning
 				}
@@ -231,6 +311,15 @@ func (service *EnitService) StartService() (err error) {
 				service.state = EnitServiceCrashed
 			}
 
+			// Reload service if needed
+			if service.shouldReload {
+				service.ReloadService()
+				if GetServiceByName(service.Name) == nil {
+					return
+				}
+				service = GetServiceByName(service.Name)
+			}
+
 			if service.Restart == "always" {
 				_ = service.StartService()
 			} else if service.Restart == "true" && service.restartCount < 5 {
@@ -258,11 +347,24 @@ func (service *EnitService) StopService() error {
 	}
 
 	logger.Printf("Stopping service (%s)...", service.Name)
+	pid := service.processID
 
 	newServiceStatus := EnitServiceCrashed
 	defer func() {
+		// Kill remaining child processes
+		syscall.Kill(-pid, syscall.SIGKILL)
+
 		service.state = newServiceStatus
 		service.processID = 0
+
+		// Reload service if needed
+		if service.shouldReload {
+			service.ReloadService()
+			if GetServiceByName(service.Name) == nil {
+				return
+			}
+			service = GetServiceByName(service.Name)
+		}
 	}()
 
 	if service.ExitMethod == "kill" {
@@ -322,10 +424,8 @@ func (service *EnitService) RestartService() error {
 	return nil
 }
 
-// Functions will be rewritten at some point to allow enabling unloaded services
-
 func (service *EnitService) isEnabled() (bool, int) {
-	for stage, services := range EnabledServices {
+	for stage, services := range ReadEnabledServices() {
 		if slices.Contains(services, service.Name) {
 			return true, stage
 		}
@@ -343,6 +443,8 @@ func (service *EnitService) SetEnabled(stage int) error {
 		return nil
 	}
 
+	EnabledServices := ReadEnabledServices()
+
 	// Remove service from current stage
 	EnabledServices[s] = slices.DeleteFunc(EnabledServices[s], func(name string) bool {
 		return name == service.Name
@@ -369,10 +471,12 @@ func (service *EnitService) SetEnabled(stage int) error {
 	return nil
 }
 
-func ReadEnabledServices() error {
+func ReadEnabledServices() (EnabledServices map[int][]string) {
+	EnabledServices = make(map[int][]string)
+
 	data, err := os.ReadFile(path.Join(serviceConfigDir, "enabled_services"))
 	if err != nil {
-		return err
+		return EnabledServices
 	}
 
 	err = yaml.Unmarshal(data, &EnabledServices)
@@ -385,15 +489,15 @@ func ReadEnabledServices() error {
 		// Update enabled_services file
 		data, err := yaml.Marshal(EnabledServices)
 		if err != nil {
-			return err
+			return EnabledServices
 		}
 		err = os.WriteFile(path.Join(serviceConfigDir, "enabled_services"), data, 0644)
 		if err != nil {
-			return err
+			return EnabledServices
 		}
 
-		return nil
+		return EnabledServices
 	}
 
-	return nil
+	return EnabledServices
 }

src/esvm/socket.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -17,6 +18,7 @@ func initSocket() (socket net.Listener, err error) {
 	}
 
 	// Register command handlers
+	commandHandlers["reload"] = handleReloadServicesCommand
 	commandHandlers["start"] = handleStartServiceCommand
 	commandHandlers["stop"] = handleStopServiceCommand
 	commandHandlers["restart"] = handleRestartServiceCommand
@@ -31,27 +33,23 @@ func listenToSocket() {
 	conn, err := socket.Accept()
 	if err != nil {
 		logger.Println("Could not accept socket connection!")
-		panic(err)
+		return
 	}
 
 	// Handle the connection in a separate goroutine.
 	go func(conn net.Conn) {
 		defer conn.Close()
-		// Create a buffer for incoming data.
-		buf := make([]byte, 4096)
 
 		// Read data from the connection.
-		n, err := conn.Read(buf)
+		data, err := readAllConn(conn)
-		if err == io.EOF {
-			return
-		}
 		if err != nil {
+			logger.Fatalf("Could not read data from socket! Error: %s\n", err)
 			return
 		}
 
 		// Decoode JSON data
 		var jsonData map[string]any
-		err = json.Unmarshal(buf[:n], &jsonData)
+		err = json.Unmarshal(data, &jsonData)
 		if err != nil {
 			conn.Write(wrapErrorInJson(fmt.Errorf("Invalid JSON")))
 			return
@@ -74,6 +72,13 @@ func listenToSocket() {
 	}(conn)
 }
 
+func handleReloadServicesCommand(conn net.Conn, jsonData map[string]any) {
+	// Reload services
+	Reload()
+
+	conn.Write(wrapSuccessMsgInJson("Services reloaded successfully"))
+}
+
 func handleStartServiceCommand(conn net.Conn, jsonData map[string]any) {
 	// Get service name from json data
 	serviceName, ok := jsonData["service"]
@@ -222,6 +227,7 @@ func handleStatusServiceCommand(conn net.Conn, jsonData map[string]any) {
 
 	statusMap := make(map[string]any)
 	statusMap["name"] = service.Name
+	statusMap["description"] = service.Description
 	statusMap["state"] = EnitServiceStateNames[service.state]
 	statusMap["process_id"] = service.processID
 	statusMap["is_enabled"], statusMap["stage"] = service.isEnabled()
@@ -244,6 +250,7 @@ func handleListServicesCommand(conn net.Conn, _ map[string]any) {
 	for _, service := range Services {
 		statusMap := make(map[string]any)
 		statusMap["name"] = service.Name
+		statusMap["description"] = service.Description
 		statusMap["state"] = EnitServiceStateNames[service.state]
 		statusMap["process_id"] = service.processID
 		statusMap["is_enabled"], statusMap["stage"] = service.isEnabled()
@@ -293,3 +300,24 @@ func wrapSuccessMsgInJson(msg string) []byte {
 	}
 	return jsonData
 }
+
+func readAllConn(conn net.Conn) ([]byte, error) {
+	var buf bytes.Buffer
+
+	for {
+		dataChunk := make([]byte, 1024)
+
+		n, err := conn.Read(dataChunk)
+		if err != nil && err != io.EOF {
+			return nil, err
+		}
+
+		buf.Write(dataChunk[:n])
+
+		if n < 1024 {
+			break
+		}
+	}
+
+	return buf.Bytes(), nil
+}