1 #ifndef EVSQL_H

     2 #define EVSQL_H

     3 

     4 /*

     5  * An event-based (Postgre)SQL client API using libevent

     6  */

     7 

     8 // XXX: libpq

     9 #include <postgresql/libpq-fe.h>

    10 #include <event2/event.h>

    11 

    12 /*

    13  * The generic context handle

    14  */

    15 struct evsql;

    16 

    17 /*

    18  * A query handle

    19  */

    20 struct evsql_query;

    21 

    22 /*

    23  * Query parameter info

    24  * /

    25 struct evsql_query_params {

    26     int count;

    27     const char * const *values;

    28     const int *lengths;

    29     const int *formats;

    30     int result_format;

    31 }; */

    32 

    33 /*

    34  * Result type

    35  */

    36 struct evsql_result_info {

    37     struct evsql *evsql;

    38     

    39     int error;

    40 

    41     union {

    42         // XXX: libpq

    43         PGresult *pq;

    44 

    45     } result;

    46 };

    47 

    48 /*

    49  * Callback for handling query-level errors.

    50  *

    51  * The query has completed, either succesfully or unsuccesfully (look at info.error).

    52  * info.result contains the result à la the evsql's type.

    53  */

    54 typedef void (*evsql_query_cb)(struct evsql_result_info info, void *arg);

    55 

    56 /*

    57  * Callback for handling connection-level errors.

    58  *

    59  * The SQL context/connection suffered an error. It is not valid anymore, and may not be used.

    60  */

    61 typedef void (*evsql_error_cb)(struct evsql *evsql, void *arg);

    62 

    63 /*

    64  * Create a new PostgreSQL/libpq(evpq) -based evsql using the given conninfo.

    65  */

    66 struct evsql *evsql_new_pq (struct event_base *ev_base, const char *pq_conninfo, evsql_error_cb error_fn, void *cb_arg);

    67 

    68 /*

    69  * Queue the given query for execution.

    70  */

    71 struct evsql_query *evsql_query (struct evsql *evsql, const char *command, evsql_query_cb query_fn, void *cb_arg);

    72 

    73 /*

    74  * Close a connection. Callbacks for waiting queries will not be run.

    75  *

    76  * XXX: not implemented yet.

    77  */

    78 void evsql_close (struct evsql *evsql);

    79 

    80 #endif /* EVSQL_H */