Added file_exists_nonempty() helper function

file_exists_nonempty() returns true if file exists
AND is nonempty.

Signed-off-by: James Yonan <[email protected]>

openvpn/common/stat.hpp

@@ -28,6 +28,22 @@ inline bool file_exists(const std::string &filename)
     return ::stat(filename.c_str(), &buffer) == 0;
 }
 
+/**
+ * Check if file exists AND is nonempty.
+ *
+ * @param filename File to check.
+ * @return true if file exists AND is nonempty.
+ */
+inline bool file_exists_nonempty(const std::string &filename)
+{
+    if (filename.empty())
+        return false;
+    struct stat s;
+    if (::stat(filename.c_str(), &s) != 0)
+        return false;
+    return s.st_size > 0;
+}
+
 // Return true if dirname is a directory
 inline bool is_directory(const std::string &pathname, const bool follow_symlinks = false)
 {