--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/evpq.h	Sat Oct 04 18:07:45 2008 +0300
@@ -0,0 +1,96 @@
+#ifndef EVPQ_H
+#define EVPQ_H
+
+/*
+ * Convenience functions for using libpq (the PostgreSQL client library) with libevent.
+ */
+
+#include <event2/event.h>
+#include <postgresql/libpq-fe.h>
+
+/*
+ * Our PGconn context wrapper.
+ */
+struct evpq_conn;
+
+/*
+ * Callback functions used
+ */
+struct evpq_callback_info {
+    /*
+     * This evpq_conn has connected succesfully \o/
+     */
+    void (*fn_connected)(struct evpq_conn *conn, void *arg);
+
+    /*
+     * Got a result.
+     */
+    void (*fn_result)(struct evpq_conn *conn, PGresult *result, void *arg);
+
+    /*
+     * No more results for the query
+     */
+    void (*fn_done)(struct evpq_conn *conn, void *arg);
+    
+    /*
+     * Something caused this evpq_conn to fail :(
+     *
+     * XXX: add a `what` arg?
+     */
+    void (*fn_failure)(struct evpq_conn *conn, void *arg);
+
+    /*
+     * Arg to pass through to all callbacks.
+     */
+    void *cb_arg;
+};
+
+/*
+ * evpq_conn states
+ */
+enum evpq_state {
+    EVPQ_INIT,
+
+    EVPQ_CONNECT,
+    EVPQ_CONNECTED,
+
+    EVPQ_QUERY,
+
+    EVPQ_FAILURE,
+};
+
+/*
+ * Create a new evpq connection.
+ *
+ * This corresponds directly to PQconnectStart, and handles all the libevent setup/polling needed.
+ *
+ * The connection will initially be in the EVPQ_CONNECT state, and will then either callback via fn_connected
+ * (EVPQ_CONNECTED) or fn_failure (EVPQ_FAILURE).
+ *
+ * cb_info contains the callback functions (and the user argument) to use.
+ */
+struct evpq_conn *evpq_connect (struct event_base *ev_base, const char *conninfo, const struct evpq_callback_info cb_info);
+
+/*
+ * Execute a query.
+ *
+ * This corresponds directly to PQsendQuery. This evpq must be in the EVPQ_CONNECTED state, so you must wait after
+ * calling evpq_connect, and you may not run two queries at the same time.
+ *
+ * The query will result in a series of fn_result (EVPQ_RESULT) calls (if multiple queries in the query string),
+ * followed by a fn_done (EVPQ_CONNECTED).
+ */
+int evpq_query (struct evpq_conn *conn, const char *command);
+
+/*
+ * Get the actual PGconn.
+ *
+ * This can safely be used to access all of the normal PQ functions.
+ */
+const PGconn *evpq_pgconn (struct evpq_conn *conn);
+
+// convenience wrappers
+#define evpq_error_message(conn) PQerrorMessage(evpq_pgconn(conn))
+
+
+#endif /* EVPQ_H */