Merge pull request #46 from iwongu/extension

Extension

README.md

@@ -314,6 +314,22 @@ sqlite3pp::query qry(
   "FROM foods");
 ```
 
+## loadable extension
+
+```cpp
+#define SQLITE3PP_LOADABLE_EXTENSION
+#include <sqlite3ppext.h>
+
+int sqlite3_extension_init(
+  sqlite3 *pdb,
+  char **pzErrMsg,
+  const sqlite3_api_routines *pApi) {
+  SQLITE_EXTENSION_INIT2(pApi);
+  sqlite3pp:database db(sqlite3pp::ext::borrow(pdb));
+  // pdb is not closed since db just borrows it.
+}
+
+```
 
 
 # See also

headeronly_src/sqlite3pp.h

@@ -25,24 +25,33 @@
 #ifndef SQLITE3PP_H
 #define SQLITE3PP_H
 
-#define SQLITE3PP_VERSION "1.0.6"
+#define SQLITE3PP_VERSION "1.0.7"
 #define SQLITE3PP_VERSION_MAJOR 1
 #define SQLITE3PP_VERSION_MINOR 0
-#define SQLITE3PP_VERSION_PATCH 6
+#define SQLITE3PP_VERSION_PATCH 7
 
 #include <functional>
 #include <iterator>
-#include <sqlite3.h>
 #include <stdexcept>
 #include <string>
 #include <tuple>
 
+#ifdef SQLITE3PP_LOADABLE_EXTENSION
+#include <sqlite3ext.h>
+SQLITE_EXTENSION_INIT1
+#else
+#  include <sqlite3.h>
+#endif
+
 namespace sqlite3pp
 {
+  class database;
+
   namespace ext
   {
     class function;
     class aggregate;
+    database borrow(sqlite3* pdb);
   }
 
   template <class T>
@@ -71,6 +80,7 @@ namespace sqlite3pp
     friend class database_error;
     friend class ext::function;
     friend class ext::aggregate;
+    friend database ext::borrow(sqlite3* pdb);
 
    public:
     using busy_handler = std::function<int (int)>;
@@ -119,8 +129,12 @@ namespace sqlite3pp
     void set_update_handler(update_handler h);
     void set_authorize_handler(authorize_handler h);
 
+   private:
+    database(sqlite3* pdb) : db_(pdb), borrowing_(true) {}
+
    private:
     sqlite3* db_;
+    bool borrowing_;
 
     busy_handler bh_;
     commit_handler ch_;

headeronly_src/sqlite3pp.ipp

@@ -64,7 +64,7 @@ namespace sqlite3pp
 
   } // namespace
 
-  inline database::database(char const* dbname, int flags, char const* vfs) : db_(nullptr)
+  inline database::database(char const* dbname, int flags, char const* vfs) : db_(nullptr), borrowing_(false)
   {
     if (dbname) {
       auto rc = connect(dbname, flags, vfs);
@@ -74,6 +74,7 @@ namespace sqlite3pp
   }
 
   inline database::database(database&& db) : db_(std::move(db.db_)),
+    borrowing_(std::move(db.borrowing_)),
     bh_(std::move(db.bh_)),
     ch_(std::move(db.ch_)),
     rh_(std::move(db.rh_)),
@@ -87,6 +88,7 @@ namespace sqlite3pp
   {
     db_ = std::move(db.db_);
     db.db_ = nullptr;
+    borrowing_ = std::move(db.borrowing_);
 
     bh_ = std::move(db.bh_);
     ch_ = std::move(db.ch_);
@@ -99,12 +101,16 @@ namespace sqlite3pp
 
   inline database::~database()
   {
-    disconnect();
+    if (!borrowing_) {
+      disconnect();
+    }
   }
 
   inline int database::connect(char const* dbname, int flags, char const* vfs)
   {
-    disconnect();
+    if (!borrowing_) {
+      disconnect();
+    }
 
     return sqlite3_open_v2(dbname, &db_, flags, vfs);
   }

headeronly_src/sqlite3ppext.h

@@ -76,6 +76,9 @@ namespace sqlite3pp
 
   namespace ext
   {
+    database borrow(sqlite3* pdb) {
+      return database(pdb);
+    }
 
     class context : noncopyable
     {

src/sqlite3pp.cpp

@@ -66,7 +66,7 @@ namespace sqlite3pp
 
   } // namespace
 
-  database::database(char const* dbname, int flags, char const* vfs) : db_(nullptr)
+  database::database(char const* dbname, int flags, char const* vfs) : db_(nullptr), borrowing_(false)
   {
     if (dbname) {
       auto rc = connect(dbname, flags, vfs);
@@ -75,7 +75,12 @@ namespace sqlite3pp
     }
   }
 
+  database::database(sqlite3* pdb) : db_(pdb), borrowing_(true)
+  {
+  }
+
   database::database(database&& db) : db_(std::move(db.db_)),
+    borrowing_(std::move(db.borrowing_)),
     bh_(std::move(db.bh_)),
     ch_(std::move(db.ch_)),
     rh_(std::move(db.rh_)),
@@ -89,7 +94,7 @@ namespace sqlite3pp
   {
     db_ = std::move(db.db_);
     db.db_ = nullptr;
-
+    borrowing_ = std::move(db.borrowing_);
     bh_ = std::move(db.bh_);
     ch_ = std::move(db.ch_);
     rh_ = std::move(db.rh_);
@@ -101,12 +106,16 @@ namespace sqlite3pp
 
   database::~database()
   {
-    disconnect();
+    if (!borrowing_) {
+      disconnect();
+    }
   }
 
   int database::connect(char const* dbname, int flags, char const* vfs)
   {
-    disconnect();
+    if (!borrowing_) {
+      disconnect();
+    }
 
     return sqlite3_open_v2(dbname, &db_, flags, vfs);
   }

src/sqlite3pp.h

@@ -25,24 +25,33 @@
 #ifndef SQLITE3PP_H
 #define SQLITE3PP_H
 
-#define SQLITE3PP_VERSION "1.0.0"
+#define SQLITE3PP_VERSION "1.0.7"
 #define SQLITE3PP_VERSION_MAJOR 1
 #define SQLITE3PP_VERSION_MINOR 0
-#define SQLITE3PP_VERSION_PATCH 6
+#define SQLITE3PP_VERSION_PATCH 7
 
 #include <functional>
 #include <iterator>
-#include <sqlite3.h>
 #include <stdexcept>
 #include <string>
 #include <tuple>
 
+#ifdef SQLITE3PP_LOADABLE_EXTENSION
+#include <sqlite3ext.h>
+SQLITE_EXTENSION_INIT1
+#else
+#  include <sqlite3.h>
+#endif
+
 namespace sqlite3pp
 {
+  class database;
+
   namespace ext
   {
     class function;
     class aggregate;
+    database borrow(sqlite3* pdb);
   }
 
   template <class T>
@@ -72,6 +81,7 @@ namespace sqlite3pp
     friend class database_error;
     friend class ext::function;
     friend class ext::aggregate;
+    friend database ext::borrow(sqlite3* pdb);
 
    public:
     using busy_handler = std::function<int (int)>;
@@ -120,8 +130,12 @@ namespace sqlite3pp
     void set_update_handler(update_handler h);
     void set_authorize_handler(authorize_handler h);
 
+   private:
+    database(sqlite3* pdb);
+
    private:
     sqlite3* db_;
+    bool borrowing_;
 
     busy_handler bh_;
     commit_handler ch_;

src/sqlite3ppext.cpp

@@ -59,6 +59,9 @@ namespace sqlite3pp
 
     } // namespace
 
+    database borrow(sqlite3* pdb) {
+      return database(pdb);
+    }
 
     context::context(sqlite3_context* ctx, int nargs, sqlite3_value** values)
       : ctx_(ctx), nargs_(nargs), values_(values)

src/sqlite3ppext.h

@@ -76,6 +76,7 @@ namespace sqlite3pp
 
   namespace ext
   {
+    database borrow(sqlite3* pdb);
 
     class context : noncopyable
     {