From b49d3e5e0e58e69b4fde856e37f73d101b5b2c0a Mon Sep 17 00:00:00 2001
From: Boris Kolpackov <boris@codesynthesis.com>
Date: Tue, 10 Aug 2010 13:57:24 +0200
Subject: Delay closing statement until there are no active statements

---
 odb/mysql/connection.cxx | 39 ++++++++++++++++++++++++++++++++++++++-
 odb/mysql/connection.hxx | 19 +++++++++++++++++++
 odb/mysql/result.txx     |  1 -
 odb/mysql/statement.cxx  |  9 ++-------
 4 files changed, 59 insertions(+), 9 deletions(-)

diff --git a/odb/mysql/connection.cxx b/odb/mysql/connection.cxx
index 7eb1b34..c6ca5a3 100644
--- a/odb/mysql/connection.cxx
+++ b/odb/mysql/connection.cxx
@@ -9,6 +9,8 @@
 #include <odb/mysql/connection.hxx>
 #include <odb/mysql/exceptions.hxx>
 
+using namespace std;
+
 namespace odb
 {
   namespace mysql
@@ -18,7 +20,7 @@ namespace odb
         : handle_ (&mysql_), active_ (0), statement_cache_ (*this)
     {
       if (mysql_init (handle_) == 0)
-        throw std::bad_alloc ();
+        throw bad_alloc ();
 
       // Force the CLIENT_FOUND_ROWS flag so that UPDATE returns the
       // number of found rows, not the number of changed rows. This
@@ -43,7 +45,42 @@ namespace odb
     connection::
     ~connection ()
     {
+      if (stmt_handles_.size () > 0)
+        free_stmt_handles ();
+
       mysql_close (handle_);
     }
+
+    MYSQL_STMT* connection::
+    alloc_stmt_handle ()
+    {
+      MYSQL_STMT* stmt (mysql_stmt_init (handle_));
+
+      if (stmt == 0)
+        throw bad_alloc ();
+
+      return stmt;
+    }
+
+    void connection::
+    free_stmt_handle (MYSQL_STMT* stmt)
+    {
+      if (active_ == 0)
+        mysql_stmt_close (stmt);
+      else
+        stmt_handles_.push_back (stmt);
+    }
+
+    void connection::
+    free_stmt_handles ()
+    {
+      for (stmt_handles::iterator i (stmt_handles_.begin ()),
+             e (stmt_handles_.end ()); i != e; ++i)
+      {
+        mysql_stmt_close (*i);
+      }
+
+      stmt_handles_.clear ();
+    }
   }
 }
diff --git a/odb/mysql/connection.hxx b/odb/mysql/connection.hxx
index 513abc5..8509790 100644
--- a/odb/mysql/connection.hxx
+++ b/odb/mysql/connection.hxx
@@ -8,6 +8,8 @@
 
 #include <mysql/mysql.h>
 
+#include <vector>
+
 #include <odb/forward.hxx>
 #include <odb/shared-ptr.hxx>
 
@@ -52,17 +54,34 @@ namespace odb
       active (statement* s)
       {
         active_ = s;
+
+        if (s == 0 && stmt_handles_.size () > 0)
+          free_stmt_handles ();
       }
 
+    public:
+      MYSQL_STMT*
+      alloc_stmt_handle ();
+
+      void
+      free_stmt_handle (MYSQL_STMT*);
+
     private:
       connection (const connection&);
       connection& operator= (const connection&);
 
     private:
+      void
+      free_stmt_handles ();
+
+    private:
       MYSQL mysql_;
       MYSQL* handle_;
       statement* active_;
       statement_cache_type statement_cache_;
+
+      typedef std::vector<MYSQL_STMT*> stmt_handles;
+      stmt_handles stmt_handles_;
     };
   }
 }
diff --git a/odb/mysql/result.txx b/odb/mysql/result.txx
index b27b22e..b85e2e0 100644
--- a/odb/mysql/result.txx
+++ b/odb/mysql/result.txx
@@ -11,7 +11,6 @@ namespace odb
     result_impl<T>::
     ~result_impl ()
     {
-      statement_->free_result ();
     }
 
     template <typename T>
diff --git a/odb/mysql/statement.cxx b/odb/mysql/statement.cxx
index 981c756..009e3f1 100644
--- a/odb/mysql/statement.cxx
+++ b/odb/mysql/statement.cxx
@@ -5,8 +5,6 @@
 
 #include <mysql/mysqld_error.h> // ER_DUP_ENTRY
 
-#include <new> // std::bad_alloc
-
 #include <odb/mysql/statement.hxx>
 #include <odb/mysql/connection.hxx>
 #include <odb/mysql/exceptions.hxx>
@@ -22,18 +20,15 @@ namespace odb
 
     statement::
     statement (connection& conn)
-        : conn_ (conn)
+        : conn_ (conn), stmt_ (conn_.alloc_stmt_handle ())
     {
-      stmt_ = mysql_stmt_init (conn_.handle ());
 
-      if (stmt_ == 0)
-        throw bad_alloc ();
     }
 
     statement::
     ~statement ()
     {
-      mysql_stmt_close (stmt_);
+      conn_.free_stmt_handle (stmt_);
     }
 
     void statement::
-- 
cgit v1.1