Server and Client daemons functional

util.go

@@ -4,12 +4,20 @@ import (
 	"errors"
 	"fmt"
 	"os"
+	"strconv"
+	"strings"
+	"syscall"
 
 	"code.gitea.io/sdk/gitea"
 	"git.nevets.tech/Steven/ezconf"
 	"github.com/google/go-github/v55/github"
 )
 
+var (
+	ErrorPIDInUse = errors.New("daemon is already running")
+	ErrLockFailed = errors.New("failed to acquire a lock on the PID file")
+)
+
 type Domain struct {
 	name        *string
 	config      *ezconf.Configuration
@@ -18,17 +26,144 @@ type Domain struct {
 	gtClient    *gitea.Client
 }
 
-type GlobalConfig struct {
-	Git struct {
-		Host     string
-		Endpoint string
-		Username string
-		Password string
-		ApiToken string
+// 0x01
+func createPIDFile() {
+	file, err := os.Create("/var/run/certman.pid")
+	if err != nil {
+		fmt.Printf("0x01: Error creating PID file: %v\n", err)
+		return
+	}
+	err = file.Close()
+	if err != nil {
+		fmt.Printf("0x01: Error closing PID file: %v\n", err)
+		return
 	}
 }
 
-type DomainConfig struct {
+// 0x02
+func clearPIDFile() {
+	file, err := os.OpenFile("/var/run/certman.pid", os.O_RDWR|os.O_CREATE, 0644)
+	if err != nil {
+		fmt.Printf("0x02: Error opening PID file: %v\n", err)
+		return
+	}
+	defer file.Close()
+
+	err = file.Truncate(0)
+	if err != nil {
+		fmt.Printf("0x02: Error writing PID file: %v\n", err)
+		return
+	}
+}
+
+// 0x03
+func createOrUpdatePIDFile(filename string) error {
+	pidBytes, err := os.ReadFile(filename)
+	if err != nil {
+		fmt.Printf("0x03: Error reading PID file: %v\n", err)
+		return err
+	}
+
+	pidStr := strings.TrimSpace(string(pidBytes))
+	isPidFileEmpty := pidStr == ""
+
+	if !isPidFileEmpty {
+		pid, err := strconv.Atoi(pidStr)
+		if err != nil {
+			fmt.Printf("0x03: Error parsing PID file: %v\n", err)
+			return err
+		}
+
+		isProcActive, err := isProcessActive(pid)
+		if err != nil {
+			fmt.Printf("0x03: Error checking if process is active: %v\n", err)
+			return err
+
+		}
+		if isProcActive {
+			return ErrorPIDInUse
+		}
+	}
+
+	pidFile, err := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, 0644)
+	if err != nil {
+		if os.IsNotExist(err) {
+			createPIDFile()
+		} else {
+			fmt.Printf("0x03: Error opening PID file: %v\n", err)
+			return err
+		}
+	}
+	defer pidFile.Close()
+
+	if err := syscall.Flock(int(pidFile.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
+		if errors.Is(err, syscall.EWOULDBLOCK) {
+			return ErrLockFailed
+		}
+		return fmt.Errorf("error locking PID file: %w", err)
+	}
+	curPid := os.Getpid()
+	if _, err := pidFile.Write([]byte(strconv.Itoa(curPid))); err != nil {
+		return fmt.Errorf("error writing pid to PID file: %w", err)
+	}
+
+	return nil
+}
+
+// 0x04
+// isProcessActive checks whether the process with the provided PID is running.
+func isProcessActive(pid int) (bool, error) {
+	if pid <= 0 {
+		return false, errors.New("invalid process ID")
+	}
+	process, err := os.FindProcess(pid)
+	if err != nil {
+		// On Unix systems, os.FindProcess always succeeds and returns a process with the given pid, irrespective of whether the process exists.
+		return false, nil
+	}
+
+	err = process.Signal(syscall.Signal(0))
+	if err != nil {
+		if errors.Is(err, syscall.ESRCH) {
+			// The process does not exist
+			return false, nil
+		} else if errors.Is(err, os.ErrProcessDone) {
+			return false, nil
+		}
+		// Some other unexpected error
+		return false, err
+	}
+
+	// The process exists and is active
+	return true, nil
+}
+
+// 0x05
+func getDaemonProcess() (*os.Process, error) {
+	pidBytes, err := os.ReadFile("/var/run/certman.pid")
+	if err != nil {
+		fmt.Printf("0x05: Error getting PID from /var/run/certman.pid: %v\n", err)
+		return nil, err
+	}
+	pidStr := strings.TrimSpace(string(pidBytes))
+	daemonPid, err := strconv.Atoi(pidStr)
+	if err != nil {
+		fmt.Printf("0x05: Error converting PID string to int (%s): %v\n", pidStr, err)
+		return nil, err
+	}
+	isProcActive, err := isProcessActive(daemonPid)
+	if err != nil {
+		fmt.Printf("0x05: Error checking if process is active: %v\n", err)
+	}
+	if !isProcActive {
+		return nil, errors.New("process is not active")
+	}
+	proc, err := os.FindProcess(daemonPid)
+	if err != nil {
+		fmt.Printf("0x05: Error finding process with PID %d: %v\n", daemonPid, err)
+		return nil, err
+	}
+	return proc, nil
 }
 
 func createFile(fileName string, filePermission os.FileMode, data []byte) {
@@ -71,16 +206,18 @@ func createFile(fileName string, filePermission os.FileMode, data []byte) {
 	}
 }
 
-func fileExists(filePath string) bool {
-	if _, err := os.Stat(filePath); err == nil {
-		return true
-	} else if errors.Is(err, os.ErrNotExist) {
-		return false
-	} else {
-		fmt.Println("Error checking file existence: ", err)
-		os.Exit(1)
-		return false
+func linkFile(source, target string) error {
+	err := os.Symlink(source, target)
+	if err != nil {
+		fmt.Println("Error creating symlink:", err)
+		return err
 	}
+	return nil
+}
+
+func fileExists(path string) bool {
+	_, err := os.Stat(path)
+	return err == nil
 }
 
 func contains(slice []string, value string) (sliceHas bool, index int) {
@@ -100,44 +237,8 @@ func insert(a []string, index int, value string) []string {
 	return a
 }
 
-const defaultConfig = `[App]
-mode = {mode}
-
-[Git]
-host = gitea
-server = https://gitea.instance.com
-username = user
-org_name = org
-template_name = template
-
-[Certificates]
-email = user@example.com
-data_root = /var/local/certman
-request_method = dns
-
-[Cloudflare]
-cf_email = email@example.com
-
-`
-
-const defaultDomainConfig = `[Domain]
-domain_name = {domain}
-; default (use system dns) or IPv4 Address (1.1.1.1)
-dns_server = default
-; optionally use /path/to/directory
-file_location = default
-
-[Certificates]
-subdomains =
-expiry = 90
-cert_symlink =
-key_symlink = 
-
-[Repo]
-repo_suffix = -certificates
-
-; Don't change setting below here unless you know what you're doing!
-[Internal]
-last_issued = never
-
-`
+func sanitizeDomainKey(s string) string {
+	s = strings.TrimSpace(strings.ToLower(s))
+	r := strings.NewReplacer("/", "_", "\\", "_", " ", "_", ":", "_")
+	return r.Replace(s)
+}