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// file : odb/pgsql/connection-factory.cxx
// copyright : Copyright (c) 2009-2015 Code Synthesis Tools CC
// license : GNU GPL v2; see accompanying LICENSE file
#include <odb/pgsql/connection-factory.hxx>
#include <odb/pgsql/exceptions.hxx>
#include <odb/details/lock.hxx>
using namespace std;
namespace odb
{
using namespace details;
namespace pgsql
{
//
// connection_factory
//
connection_factory::
~connection_factory ()
{
}
//
// new_connection_factory
//
connection_ptr new_connection_factory::
connect ()
{
return connection_ptr (new (shared) connection (*db_));
}
void new_connection_factory::
database (database_type& db)
{
db_ = &db;
}
//
// connection_pool_factory
//
connection_pool_factory::pooled_connection_ptr connection_pool_factory::
create ()
{
return pooled_connection_ptr (new (shared) pooled_connection (*db_));
}
connection_pool_factory::
~connection_pool_factory ()
{
// Wait for all the connections currently in use to return to
// the pool.
//
lock l (mutex_);
while (in_use_ != 0)
{
waiters_++;
cond_.wait ();
waiters_--;
}
}
connection_ptr connection_pool_factory::
connect ()
{
lock l (mutex_);
while (true)
{
// See if we have a spare connection.
//
if (connections_.size () != 0)
{
shared_ptr<pooled_connection> c (connections_.back ());
connections_.pop_back ();
c->pool_ = this;
in_use_++;
return c;
}
// See if we can create a new one.
//
if (max_ == 0 || in_use_ < max_)
{
shared_ptr<pooled_connection> c (create ());
c->pool_ = this;
in_use_++;
return c;
}
// Wait until someone releases a connection.
//
waiters_++;
cond_.wait ();
waiters_--;
}
}
void connection_pool_factory::
database (database_type& db)
{
db_ = &db;
if (min_ > 0)
{
connections_.reserve (min_);
for (size_t i (0); i < min_; ++i)
connections_.push_back (create ());
}
}
bool connection_pool_factory::
release (pooled_connection* c)
{
c->pool_ = 0;
lock l (mutex_);
// Determine if we need to keep or free this connection.
//
bool keep (!c->failed () &&
(waiters_ != 0 ||
min_ == 0 ||
(connections_.size () + in_use_ <= min_)));
in_use_--;
if (keep)
{
connections_.push_back (pooled_connection_ptr (inc_ref (c)));
connections_.back ()->recycle ();
}
if (waiters_ != 0)
cond_.signal ();
return !keep;
}
//
// connection_pool_factory::pooled_connection
//
connection_pool_factory::pooled_connection::
pooled_connection (database_type& db)
: connection (db), pool_ (0)
{
callback_.arg = this;
callback_.zero_counter = &zero_counter;
shared_base::callback_ = &callback_;
}
connection_pool_factory::pooled_connection::
pooled_connection (database_type& db, PGconn* handle)
: connection (db, handle), pool_ (0)
{
callback_.arg = this;
callback_.zero_counter = &zero_counter;
shared_base::callback_ = &callback_;
}
bool connection_pool_factory::pooled_connection::
zero_counter (void* arg)
{
pooled_connection* c (static_cast<pooled_connection*> (arg));
return c->pool_ ? c->pool_->release (c) : true;
}
}
}
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