Added update_size() to string API to fix string lengths after insertion of characters by C code.

include/etl/basic_string.h

@@ -2184,6 +2184,23 @@ namespace etl
     virtual void repair() = 0;
 #endif
 
+    //*********************************************************************
+    /// Update the size to the distnace to the first null, or max size.
+    //*********************************************************************
+    void update_size()
+    {
+      p_buffer[max_size()] = 0; // Ensure a terminating null.
+
+      size_t i = 0U;
+
+      while ((i != max_size()) && (p_buffer[i] != 0))
+      {
+        ++i;
+      }
+
+      current_size = i;
+    }
+
   protected:
 
     //*********************************************************************
@@ -2200,7 +2217,7 @@ namespace etl
     //*********************************************************************
     void initialise()
     {
-      current_size = 0;
+      current_size = 0U;
       cleanup();
       p_buffer[0] = 0;
 #if ETL_STRING_TRUNCATION_CHECKS_ENABLED

test/test_string_char.cpp

@@ -4156,7 +4156,42 @@ namespace
       CHECK(text3.is_secure());
       CHECK(text4.is_secure());
     }
-
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_char_external_buffer.cpp

@@ -4519,5 +4519,44 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_u16.cpp

@@ -4157,5 +4157,41 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_u16_external_buffer.cpp

@@ -4519,5 +4519,44 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_u32.cpp

@@ -4157,5 +4157,41 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_u32_external_buffer.cpp

@@ -4502,5 +4502,44 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_wchar_t.cpp

@@ -4157,5 +4157,41 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      Text text;
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }

test/test_string_wchar_t_external_buffer.cpp

@@ -4502,5 +4502,44 @@ namespace
       CHECK(text4.is_secure());
     }
 #endif
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_max_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size(), STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_shorter_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() - 1, STR('A'));
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size() - 1, text.size());
+    }
+
+    //*************************************************************************
+    TEST_FIXTURE(SetupFixture, test_update_after_c_string_greater_size)
+    {
+      TextBuffer buffer;
+      Text text(buffer.data(), buffer.size());
+
+      text.resize(text.max_size());
+      std::fill(text.data(), text.data() + text.max_size() + 1, STR('A')); // Overwrites to terminating null.
+      text.update_size();
+
+      CHECK_EQUAL(text.max_size(), text.size());
+    }
   };
 }