Add my Utils.h file to define nullptr on C++98 and C++03 compilers

Author: SRombauts

CMakeLists.txt

@@ -122,6 +122,7 @@ set(SQLITECPP_INC
  ${PROJECT_SOURCE_DIR}/include/SQLiteCpp/Exception.h
  ${PROJECT_SOURCE_DIR}/include/SQLiteCpp/Statement.h
  ${PROJECT_SOURCE_DIR}/include/SQLiteCpp/Transaction.h
+ ${PROJECT_SOURCE_DIR}/include/SQLiteCpp/Utils.h
  ${PROJECT_SOURCE_DIR}/include/SQLiteCpp/VariadicBind.h
 )
 source_group(inc FILES ${SQLITECPP_INC})

include/SQLiteCpp/Database.h

@@ -3,14 +3,15 @@
  * @ingroup SQLiteCpp
  * @brief   Management of a SQLite Database Connection.
  *
- * Copyright (c) 2012-2016 Sebastien Rombauts ([email protected])
+ * Copyright (c) 2012-2017 Sebastien Rombauts ([email protected])
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
  */
 #pragma once
 
 #include <SQLiteCpp/Column.h>
+#include <SQLiteCpp/Utils.h>    // definition of nullptr for C++98/C++03 compilers
 
 #include <string.h>
 
@@ -95,7 +96,7 @@ class Database
     Database(const char* apFilename,
              const int   aFlags         = SQLite::OPEN_READONLY,
              const int   aBusyTimeoutMs = 0,
-             const char* apVfs          = NULL);
+             const char* apVfs          = nullptr);
 
     /**
      * @brief Open the provided database UTF-8 filename.
@@ -309,10 +310,10 @@ class Database
      * @param[in] aNbArg        Number of arguments in the function
      * @param[in] abDeterministic Optimize for deterministic functions (most are). A random number generator is not.
      * @param[in] apApp         Arbitrary pointer of user data, accessible with sqlite3_user_data().
-     * @param[in] apFunc        Pointer to a C-function to implement a scalar SQL function (apStep & apFinal NULL)
-     * @param[in] apStep        Pointer to a C-function to implement an aggregate SQL function (apFunc NULL)
-     * @param[in] apFinal       Pointer to a C-function to implement an aggregate SQL function (apFunc NULL)
-     * @param[in] apDestroy     If not NULL, then it is the destructor for the application data pointer.
+     * @param[in] apFunc        Pointer to a C-function to implement a scalar SQL function (apStep & apFinal nullptr)
+     * @param[in] apStep        Pointer to a C-function to implement an aggregate SQL function (apFunc nullptr)
+     * @param[in] apFinal       Pointer to a C-function to implement an aggregate SQL function (apFunc nullptr)
+     * @param[in] apDestroy     If not nullptr, then it is the destructor for the application data pointer.
      *
      * @throw SQLite::Exception in case of error
      */
@@ -337,10 +338,10 @@ class Database
      * @param[in] aNbArg        Number of arguments in the function
      * @param[in] abDeterministic Optimize for deterministic functions (most are). A random number generator is not.
      * @param[in] apApp         Arbitrary pointer of user data, accessible with sqlite3_user_data().
-     * @param[in] apFunc        Pointer to a C-function to implement a scalar SQL function (apStep & apFinal NULL)
-     * @param[in] apStep        Pointer to a C-function to implement an aggregate SQL function (apFunc NULL)
-     * @param[in] apFinal       Pointer to a C-function to implement an aggregate SQL function (apFunc NULL)
-     * @param[in] apDestroy     If not NULL, then it is the destructor for the application data pointer.
+     * @param[in] apFunc        Pointer to a C-function to implement a scalar SQL function (apStep & apFinal nullptr)
+     * @param[in] apStep        Pointer to a C-function to implement an aggregate SQL function (apFunc nullptr)
+     * @param[in] apFinal       Pointer to a C-function to implement an aggregate SQL function (apFunc nullptr)
+     * @param[in] apDestroy     If not nullptr, then it is the destructor for the application data pointer.
      *
      * @throw SQLite::Exception in case of error
      */
@@ -368,7 +369,7 @@ class Database
      * @note UTF-8 text encoding assumed.
      *
      * @param[in] apExtensionName   Name of the shared library containing extension
-     * @param[in] apEntryPointName  Name of the entry point (NULL to let sqlite work it out)
+     * @param[in] apEntryPointName  Name of the entry point (nullptr to let sqlite work it out)
      *
      * @throw SQLite::Exception in case of error
      */

include/SQLiteCpp/Utils.h

@@ -0,0 +1,67 @@
+/**
+ * @file    Utils.h
+ * @ingroup SQLiteCpp
+ * @brief   Shared utility macros and functions.
+ *
+ * Copyright (c) 2013-2017 Sebastien Rombauts ([email protected])
+ *
+ * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
+ * or copy at http://opensource.org/licenses/MIT)
+ */
+#pragma once
+
+#include <cstddef>
+
+/**
+ * @brief A macro to disallow the copy constructor and operator= functions.
+ *
+ * This should be used in the private: declarations for a class
+ *
+ * @param[in] TypeName  Class name to protect
+ */
+#define DISALLOW_COPY_AND_ASSIGN(TypeName)  \
+    TypeName(const TypeName&);              \
+    void operator=(const TypeName&)
+
+#ifdef _MSC_VER
+#if _MSC_VER < 1600
+/// A macro to enable the use of the nullptr keyword (NULL on older MSVC compilers, as they do not accept "nullptr_t")
+#ifndef nullptr
+#define nullptr NULL
+#endif  // nullptr
+#endif  // _MSC_VER < 1600
+#else   // _MSC_VER
+#if (__cplusplus < 201103L) && !defined(__GXX_EXPERIMENTAL_CXX0X__) // before C++11 on GCC4.7 and Visual Studio 2010
+#ifndef HAVE_NULLPTR
+#define HAVE_NULLPTR    ///< A macro to avoid double definition of nullptr
+/**
+ * @brief nullptr_t is the type of the null pointer literal, nullptr.
+*/
+class nullptr_t {
+public:
+    template<typename T>
+    inline operator T* () const {       ///< convertible to any type of null non-member pointer...
+        return 0;
+    }
+
+    template<typename C, typename T>
+    inline operator T C::* () const {   ///< convertible to any type of null member pointer...
+        return 0;
+    }
+
+private:
+    void operator&() const;  ///< Can't take address of nullptr NOLINT
+};
+
+/**
+ * @brief Better way to enable nullptr on older GCC/Clang compilers
+*/
+const nullptr_t nullptr = {};
+#endif // HAVE_NULLPTR
+#endif // (__cplusplus < 201103L) && !defined(__GXX_EXPERIMENTAL_CXX0X__)
+#endif // _MSC_VER
+
+// A macro for snprintf support in Visual Studio
+#if _MSC_VER
+#define snprintf _snprintf
+#endif

src/Database.cpp

@@ -3,7 +3,7 @@
  * @ingroup SQLiteCpp
  * @brief   Management of a SQLite Database Connection.
  *
- * Copyright (c) 2012-2016 Sebastien Rombauts ([email protected])
+ * Copyright (c) 2012-2017 Sebastien Rombauts ([email protected])
  *
  * Distributed under the MIT License (MIT) (See accompanying file LICENSE.txt
  * or copy at http://opensource.org/licenses/MIT)
@@ -53,8 +53,8 @@ int getLibVersionNumber() noexcept // nothrow
 Database::Database(const char* apFilename,
                    const int   aFlags         /* = SQLite::OPEN_READONLY*/,
                    const int   aBusyTimeoutMs /* = 0 */,
-                   const char* apVfs          /* = NULL*/) :
-    mpSQLite(NULL),
+                   const char* apVfs          /* = nullptr*/) :
+    mpSQLite(nullptr),
     mFilename(apFilename)
 {
     const int ret = sqlite3_open_v2(apFilename, &mpSQLite, aFlags, apVfs);
@@ -75,10 +75,10 @@ Database::Database(const std::string& aFilename,
                    const int          aFlags         /* = SQLite::OPEN_READONLY*/,
                    const int          aBusyTimeoutMs /* = 0 */,
                    const std::string& aVfs           /* = "" */) :
-    mpSQLite(NULL),
+    mpSQLite(nullptr),
     mFilename(aFilename)
 {
-    const int ret = sqlite3_open_v2(aFilename.c_str(), &mpSQLite, aFlags, aVfs.empty() ? NULL : aVfs.c_str());
+    const int ret = sqlite3_open_v2(aFilename.c_str(), &mpSQLite, aFlags, aVfs.empty() ? nullptr : aVfs.c_str());
     if (SQLITE_OK != ret)
     {
         const SQLite::Exception exception(mpSQLite, ret); // must create before closing
@@ -126,7 +126,7 @@ void Database::setBusyTimeout(const int aBusyTimeoutMs)
 // Shortcut to execute one or multiple SQL statements without results (UPDATE, INSERT, ALTER, COMMIT, CREATE...).
 int Database::exec(const char* apQueries)
 {
-    const int ret = sqlite3_exec(mpSQLite, apQueries, NULL, NULL, NULL);
+    const int ret = sqlite3_exec(mpSQLite, apQueries, nullptr, nullptr, nullptr);
     check(ret);
 
     // Return the number of rows modified by those SQL statements (INSERT, UPDATE or DELETE only)
@@ -217,12 +217,12 @@ void Database::loadExtension(const char* apExtensionName, const char *apEntryPoi
 
     throw std::runtime_error("sqlite extensions are disabled");
 #else
-#ifdef SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION // Since SQLite 3.13 (2016-05-18):
+#ifdef SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION // Since SQLite 3.13 (2017-05-18):
     // Security warning:
     // It is recommended that the SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION method be used to enable only this interface.
     // The use of the sqlite3_enable_load_extension() interface should be avoided to keep the SQL load_extension()
     // disabled and prevent SQL injections from giving attackers access to extension loading capabilities.
-    int ret = sqlite3_db_config(mpSQLite, SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION, 1, NULL);
+    int ret = sqlite3_db_config(mpSQLite, SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION, 1, nullptr);
 #else
     int ret = sqlite3_enable_load_extension(mpSQLite, 1);
 #endif