CFG_VER/APP_VER in the env file: invalid configs replaced, updates follow APP_VER (dev/stable/pin)

internal/service/envfile.go

@@ -0,0 +1,47 @@
+// Shared env-file handling for the installers (Windows and Linux).
+package service
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"gpu-turnstile/internal/config"
+)
+
+// syncEnvFile ensures the installed env file at path is a current
+// installer-written sample. A missing file is created; a file without a
+// CFG_VER line (hand-written or from before versioning) is invalid and
+// replaced by a fresh sample after a .bak backup; a file written by an
+// older version gets newly added settings appended via config.SyncSample.
+// logPath activates the LOG_FILE line (Windows); empty leaves it commented.
+func syncEnvFile(path, version, logPath string) error {
+	data, err := os.ReadFile(path)
+	switch {
+	case os.IsNotExist(err):
+		return writeEnvFile(path, config.SampleEnv(version, logPath))
+	case err != nil:
+		return fmt.Errorf("read %s: %w", path, err)
+	}
+	values, perr := config.ParseEnvFile(strings.NewReader(string(data)))
+	if perr == nil && values["CFG_VER"] != "" {
+		synced, changed := config.SyncSample(string(data), version, logPath)
+		if !changed {
+			return nil
+		}
+		return writeEnvFile(path, synced)
+	}
+	// No readable CFG_VER: the file is invalid — keep a backup and start
+	// from a fresh sample.
+	if err := os.WriteFile(path+".bak", data, 0o644); err != nil {
+		return fmt.Errorf("back up %s: %w", path, err)
+	}
+	return writeEnvFile(path, config.SampleEnv(version, logPath))
+}
+
+func writeEnvFile(path, content string) error {
+	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
+		return fmt.Errorf("write %s: %w", path, err)
+	}
+	return nil
+}

internal/service/service_linux.go

@@ -15,8 +15,6 @@ import (
 	"os/signal"
 	"path/filepath"
 	"syscall"
-
-	"gpu-turnstile/internal/config"
 )
 
 // Name matches the Windows service name; the systemd unit is Name + ".service".
@@ -172,26 +170,16 @@ func Install(configPath string, copyBin bool, version string) error {
 			}
 		}
 		exe = installedExe
-		data, readErr := os.ReadFile(etcConfig)
-		switch {
-		case os.IsNotExist(readErr):
-			if configPath != "" {
-				copyFile(configPath, etcConfig, 0o644) //nolint:errcheck // best effort
-			} else if err := os.WriteFile(etcConfig, []byte(config.SampleEnv(version, "")), 0o644); err != nil {
-				// Fully commented sample covering every setting; LOG_FILE
-				// stays commented — stderr goes to the journal on Linux.
-				return fmt.Errorf("write %s: %w", etcConfig, err)
-			}
-		case readErr != nil:
-			return fmt.Errorf("read %s: %w", etcConfig, readErr)
-		default:
-			// An installer-written config from an older version gets any
-			// new settings appended; hand-written files stay untouched.
-			if synced, changed := config.SyncSample(string(data), version, ""); changed {
-				if err := os.WriteFile(etcConfig, []byte(synced), 0o644); err != nil {
-					return fmt.Errorf("write %s: %w", etcConfig, err)
-				}
-			}
+		if _, err := os.Stat(etcConfig); os.IsNotExist(err) && configPath != "" {
+			copyFile(configPath, etcConfig, 0o644) //nolint:errcheck // best effort
+		}
+		// Missing configs get a fully commented sample (LOG_FILE stays
+		// commented — stderr goes to the journal on Linux);
+		// installer-written ones from older versions get new settings
+		// appended; anything without CFG_VER is invalid and gets replaced
+		// (backup kept as .bak).
+		if err := syncEnvFile(etcConfig, version, ""); err != nil {
+			return err
 		}
 	} else if configPath != "" {
 		if abs, absErr := filepath.Abs(configPath); absErr == nil {

internal/service/service_windows.go

@@ -172,28 +172,14 @@ func Install(configPath string, copyBin bool, version string) error {
 				}
 			}
 		}
-		// A service has no console: without LOG_FILE the output vanishes.
-		// With no config at all, install a fully commented sample covering
-		// every setting (only LOG_FILE active). An existing installer-written
-		// config from an older version gets any new settings appended; any
-		// other existing config just gets a LOG_FILE line if it has none.
+		// A service has no console: without LOG_FILE the output vanishes, so
+		// the sample pre-wires it to ProgramData. Missing configs get a
+		// fresh sample; installer-written ones from older versions get new
+		// settings appended; anything without CFG_VER is invalid and gets
+		// replaced (backup kept as .bak).
 		logPath := filepath.Join(dataDir, "gpu-turnstile.log")
-		data, readErr := os.ReadFile(targetCfg)
-		switch {
-		case os.IsNotExist(readErr):
-			if err := os.WriteFile(targetCfg, []byte(config.SampleEnv(version, logPath)), 0o644); err != nil {
-				return fmt.Errorf("write %s: %w", targetCfg, err)
-			}
-		case readErr != nil:
-			return fmt.Errorf("read %s: %w", targetCfg, readErr)
-		default:
-			if synced, changed := config.SyncSample(string(data), version, logPath); changed {
-				if err := os.WriteFile(targetCfg, []byte(synced), 0o644); err != nil {
-					return fmt.Errorf("write %s: %w", targetCfg, err)
-				}
-			} else if err := ensureLogFile(targetCfg, logPath); err != nil {
-				return err
-			}
+		if err := syncEnvFile(targetCfg, version, logPath); err != nil {
+			return err
 		}
 		configPath = targetCfg
 	}
@@ -329,30 +315,6 @@ func sameFileContent(a, b string) (bool, error) {
 	return bytes.Equal(ba, bb), nil
 }
 
-// ensureLogFile makes sure the env file at path sets LOG_FILE, creating
-// the file or appending the line as needed. An existing LOG_FILE= line
-// (even an empty one) is respected and left untouched.
-func ensureLogFile(path, logPath string) error {
-	data, err := os.ReadFile(path)
-	if err != nil && !os.IsNotExist(err) {
-		return fmt.Errorf("read %s: %w", path, err)
-	}
-	for _, line := range strings.Split(string(data), "\n") {
-		if strings.HasPrefix(strings.TrimSpace(line), "LOG_FILE=") {
-			return nil
-		}
-	}
-	s := string(data)
-	if s != "" && !strings.HasSuffix(s, "\n") {
-		s += "\n"
-	}
-	s += "LOG_FILE=" + logPath + "\n"
-	if err := os.WriteFile(path, []byte(s), 0o644); err != nil {
-		return fmt.Errorf("write %s: %w", path, err)
-	}
-	return nil
-}
-
 // copyFile copies src to dst (0755 on the new file).
 func copyFile(src, dst string) error {
 	in, err := os.Open(src)