feat: create standalone native fnOS repository

app-src/internal/nginx/syntax.go

@@ -0,0 +1,68 @@
+package nginx
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ValidateConfigSyntax performs a lightweight syntax check when nginx -t is unavailable.
+func ValidateConfigSyntax(content string) error {
+	depth := 0
+	for i, raw := range strings.Split(content, "\n") {
+		trimmed := strings.TrimSpace(raw)
+		if trimmed == "" || strings.HasPrefix(trimmed, "#") {
+			continue
+		}
+		line := stripInlineComment(trimmed)
+		if line == "" {
+			continue
+		}
+		depth += strings.Count(line, "{") - strings.Count(line, "}")
+		if depth < 0 {
+			return fmt.Errorf("第 %d 行：多余的 `}`", i+1)
+		}
+		if err := validateConfigLine(line, i+1); err != nil {
+			return err
+		}
+	}
+	if depth != 0 {
+		return fmt.Errorf("配置块大括号未配对")
+	}
+	return nil
+}
+
+func stripInlineComment(line string) string {
+	inSingle := false
+	inDouble := false
+	for i := 0; i < len(line); i++ {
+		ch := line[i]
+		switch ch {
+		case '\'':
+			if !inDouble {
+				inSingle = !inSingle
+			}
+		case '"':
+			if !inSingle {
+				inDouble = !inDouble
+			}
+		case '#':
+			if !inSingle && !inDouble {
+				return strings.TrimSpace(line[:i])
+			}
+		}
+	}
+	return strings.TrimSpace(line)
+}
+
+func validateConfigLine(line string, lineNo int) error {
+	if line == "}" || line == "{" {
+		return nil
+	}
+	if strings.HasSuffix(line, "{") {
+		return nil
+	}
+	if strings.HasSuffix(line, ";") {
+		return nil
+	}
+	return fmt.Errorf("第 %d 行：无效的 Nginx 语法（应以 ; 或 { 结尾）", lineNo)
+}