Change default config location (again); support auto-locating and moving old configs

cmd/config_finder.go

@@ -0,0 +1,60 @@
+package cmd
+
+import (
+	"github.com/pterodactyl/wings/config"
+	"os"
+	"path/filepath"
+)
+
+// We've gone through a couple of iterations of where the configuration is stored. This
+// helpful little function will look through the three areas it might have ended up, and
+// return it.
+//
+// We only run this if the configuration flag for the instance is not actually passed in
+// via the command line. Once found, the configuration is moved into the expected default
+// location. Only errors are returned from this function, you can safely assume that after
+// running this the configuration can be found in the correct default location.
+func RelocateConfiguration() error {
+	var match string
+	check := []string{
+		config.DefaultLocation,
+		"/var/lib/pterodactyl/config.yml",
+		"/etc/wings/config.yml",
+	}
+
+	// Loop over all of the configuration paths, and return which one we found, if
+	// any.
+	for _, p := range check {
+		if s, err := os.Stat(p); err != nil {
+			if !os.IsNotExist(err) {
+				return err
+			}
+		} else if !s.IsDir() {
+			match = p
+			break
+		}
+	}
+
+	// Just return a generic not exist error at this point if we didn't have a match, this
+	// will allow the caller to handle displaying a more friendly error to the user. If we
+	// did match in the default location, go ahead and return successfully.
+	if match == "" {
+		return os.ErrNotExist
+	} else if match == config.DefaultLocation {
+		return nil
+	}
+
+	// The rest of this function simply creates the new default location and moves the
+	// old configuration file over to the new location, then sets the permissions on the
+	// file correctly so that only the user running this process can read it.
+	p, _ := filepath.Split(config.DefaultLocation)
+	if err := os.MkdirAll(p, 0755); err != nil {
+		return err
+	}
+
+	if err := os.Rename(match, config.DefaultLocation); err != nil {
+		return err
+	}
+
+	return os.Chmod(config.DefaultLocation, 0600)
+}