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// file : odb/sqlite/transaction-impl.cxx
// license : GNU GPL v2; see accompanying LICENSE file
#include <sqlite3.h>
#include <odb/sqlite/database.hxx>
#include <odb/sqlite/connection.hxx>
#include <odb/sqlite/statement.hxx>
#include <odb/sqlite/statement-cache.hxx>
#include <odb/sqlite/transaction-impl.hxx>
namespace odb
{
namespace sqlite
{
transaction_impl::
transaction_impl (database_type& db, lock l)
: odb::transaction_impl (db), lock_ (l)
{
}
transaction_impl::
transaction_impl (connection_ptr c, lock l)
: odb::transaction_impl (c->database (), *c),
connection_ (c),
lock_ (l)
{
}
transaction_impl::
~transaction_impl ()
{
}
void transaction_impl::
start ()
{
// Grab a connection if we don't already have one.
//
if (connection_ == 0)
{
connection_ = static_cast<database_type&> (database_).connection ();
odb::transaction_impl::connection_ = connection_.get ();
}
statement_cache& sc (connection_->statement_cache ());
switch (lock_)
{
case deferred:
{
sc.begin_statement ().execute ();
break;
}
case immediate:
{
sc.begin_immediate_statement ().execute ();
break;
}
case exclusive:
{
sc.begin_exclusive_statement ().execute ();
break;
}
}
}
// In SQLite, when a commit fails (e.g., because of the deferred
// foreign key constraint violation), the transaction may not
// be automatically rolled back. So we have to do it ourselves.
//
struct commit_guard
{
commit_guard (connection& c): c_ (&c) {}
void release () {c_ = 0;}
~commit_guard ()
{
if (c_ != 0 && sqlite3_get_autocommit (c_->handle ()) == 0)
{
// This is happening while another exception is active.
//
try
{
c_->statement_cache ().rollback_statement ().execute ();
}
catch (...) {}
}
}
private:
connection* c_;
};
void transaction_impl::
commit ()
{
// Invalidate query results and reset active statements.
//
// Active statements will prevent COMMIT from completing (write
// statements) or releasing the locks (read statements). Normally, a
// statement is automatically reset on completion, however, if an
// exception is thrown, that may not happen.
//
connection_->clear ();
{
commit_guard cg (*connection_);
connection_->statement_cache ().commit_statement ().execute ();
cg.release ();
}
// Release the connection.
//
connection_.reset ();
}
void transaction_impl::
rollback ()
{
// Invalidate query results and reset active statements (the same
// reasoning as in commit()).
//
connection_->clear ();
connection_->statement_cache ().rollback_statement ().execute ();
// Release the connection.
//
connection_.reset ();
}
}
}
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