diff --git a/lib/preprocessor.cpp b/lib/preprocessor.cpp
index d3bc04705..683247300 100644
--- a/lib/preprocessor.cpp
+++ b/lib/preprocessor.cpp
@@ -1300,14 +1300,14 @@ std::string Preprocessor::getcode(const std::string &filedata, std::string cfg,
     return expandMacros(ret.str(), filename, errorLogger);
 }
 
-int Preprocessor::getHeaderFileName(std::string &str)
+Preprocessor::HeaderTypes Preprocessor::getHeaderFileName(std::string &str)
 {
     std::string result;
     std::string::size_type i = str.find_first_of("<\"");
     if (i == std::string::npos)
     {
         str = "";
-        return 0;
+        return NoHeader;
     }
 
     unsigned char c = str[i];
@@ -1324,9 +1324,9 @@ int Preprocessor::getHeaderFileName(std::string &str)
 
     str = result;
     if (c == '"')
-        return 1;
+        return UserHeader;
     else
-        return 2;
+        return SystemHeader;
 }
 
 
@@ -1373,8 +1373,8 @@ void Preprocessor::handleIncludes(std::string &code, const std::string &filePath
         // Remove #include clause
         code.erase(pos, end - pos);
 
-        int headerType = getHeaderFileName(filename);
-        if (headerType == 0)
+        HeaderTypes headerType = getHeaderFileName(filename);
+        if (headerType == NoHeader)
             continue;
 
         // filename contains now a file name e.g. "menu.h"
@@ -1394,7 +1394,7 @@ void Preprocessor::handleIncludes(std::string &code, const std::string &filePath
             fin.clear();
         }
 
-        if (headerType == 1 && !fileOpened)
+        if (headerType == UserHeader && !fileOpened)
         {
             filename = paths.back() + filename;
 
@@ -1445,7 +1445,7 @@ void Preprocessor::handleIncludes(std::string &code, const std::string &filePath
         }
         else if (!fileOpened)
         {
-            if (headerType == 1 && _errorLogger && _settings && _settings->_verbose)
+            if (headerType == UserHeader && _errorLogger && _settings && _settings->_verbose)
             {
                 _errorLogger->reportOut("Include file: \"" + filename + "\" not found.");
             }
diff --git a/lib/preprocessor.h b/lib/preprocessor.h
index e180c7a22..da5215bfc 100644
--- a/lib/preprocessor.h
+++ b/lib/preprocessor.h
@@ -31,10 +31,25 @@
 /// @addtogroup Core
 /// @{
 
-/** @brief The cppcheck preprocessor. It has special functionality for extracting the various ifdef configurations that exist in a source file. */
+/**
+ * @brief The cppcheck preprocessor.
+ * The preprocessor has special functionality for extracting the various ifdef
+ * configurations that exist in a source file.
+ */
 class Preprocessor
 {
 public:
+
+    /**
+     * Include file types.
+     */
+    enum HeaderTypes
+    {
+        NoHeader = 0,
+        UserHeader,
+        SystemHeader
+    };
+
     Preprocessor(Settings *settings = 0, ErrorLogger *errorLogger = 0);
 
     /**
@@ -147,11 +162,11 @@ protected:
      * Returns the string between double quote characters or \< \> characters.
      * @param str e.g. \code#include "menu.h"\endcode or \code#include <menu.h>\endcode
      * After function call it will contain e.g. "menu.h" without double quotes.
-     * @return 0 empty string if double quotes or \< \> were not found.
-     *         1 if file surrounded with "" was found
-     *         2 if file surrounded with \<\> was found
+     * @return NoHeader empty string if double quotes or \< \> were not found.
+     *         UserHeader if file surrounded with "" was found
+     *         SystemHeader if file surrounded with \<\> was found
      */
-    static int getHeaderFileName(std::string &str);
+    static Preprocessor::HeaderTypes getHeaderFileName(std::string &str);
 private:
 
     /**
diff --git a/test/testpreprocessor.cpp b/test/testpreprocessor.cpp
index b1ca419bf..f7c504fdd 100644
--- a/test/testpreprocessor.cpp
+++ b/test/testpreprocessor.cpp
@@ -2015,19 +2015,19 @@ private:
     {
         {
             std::string src = "#include a.h";
-            ASSERT_EQUALS(0, OurPreprocessor::getHeaderFileName(src));
+            ASSERT_EQUALS(OurPreprocessor::NoHeader, OurPreprocessor::getHeaderFileName(src));
             ASSERT_EQUALS("", src);
         }
 
         {
             std::string src = "#include \"b.h\"";
-            ASSERT_EQUALS(1, OurPreprocessor::getHeaderFileName(src));
+            ASSERT_EQUALS(OurPreprocessor::UserHeader, OurPreprocessor::getHeaderFileName(src));
             ASSERT_EQUALS("b.h", src);
         }
 
         {
             std::string src = "#include <c.h>";
-            ASSERT_EQUALS(2, OurPreprocessor::getHeaderFileName(src));
+            ASSERT_EQUALS(OurPreprocessor::SystemHeader, OurPreprocessor::getHeaderFileName(src));
             ASSERT_EQUALS("c.h", src);
         }
     }