Added a pre-ellipsis function in the utils.

common/utils/UtilsTest.cpp

@@ -656,6 +656,7 @@ TEST_F(cta_UtilsTest, ellipses) {
   ASSERT_EQ("1234567890", midEllipsis("1234567890", 12));
   ASSERT_EQ("123[...]CDEF", midEllipsis("1234567890ABCDEF", 12));
   ASSERT_EQ("1[...]ABCDEF", midEllipsis("1234567890ABCDEF", 12, 1));
+  ASSERT_EQ("[...]0ABCDEF", preEllipsis("1234567890ABCDEF", 12));
 }
 
 } // namespace unitTests

common/utils/utils.cpp

@@ -285,6 +285,18 @@ std::string midEllipsis(const std::string &s, size_t maxSize, size_t beginingSiz
   return s.substr(0, beginingSize) + ellipsis + s.substr(s.size() - maxSize + ellipsis.size() + beginingSize);
 }
 
+//------------------------------------------------------------------------------
+// preEllipsis
+//------------------------------------------------------------------------------
+std::string preEllipsis(const std::string &s, size_t maxSize) {
+  std::string ellipsis = "[...]";
+  if (maxSize < ellipsis.size())
+    throw cta::exception::Exception("In cta::utils::postEllipsis(): maxSize cannot be smaller than ellipsis size");
+  if (s.size() <= maxSize)
+    return s;
+  return ellipsis + s.substr(s.size() - maxSize + ellipsis.size());
+}
+
 //------------------------------------------------------------------------------
 // singleSpaceString
 //------------------------------------------------------------------------------

common/utils/utils.hpp

@@ -132,8 +132,18 @@ namespace utils {
    * @param beginingSize
    * @return the ellipsed string
    */
-  
   std::string midEllipsis(const std::string &s, size_t maxSize, size_t beginingSize = 0);
+  
+  /**
+   * Returns a string with an ellipsis in the beginning if necessary so that the 
+   * string plus ellipsis does not exceed the maxSize. The returned string is 
+   * identical to s if it fits the maximum size.
+   * @param s the string
+   * @param maxSize
+   * @return the ellipsed string
+   */
+  std::string preEllipsis(const std::string &s, size_t maxSize);
+  
   /**
    * Returns uuid in the form of a string.
    *