1

     2

#include <stdio.h>

     3

     4

#include "evpq.h"

     5

#include "lib/log.h"

     6

     7

#define CONNINFO_DEFAULT "dbname=test"

     8

#define QUERY_DEFAULT "SELECT a, b FROM foo"

     9

    10

void cb_connected (struct evpq_conn *conn, void *arg) {

    11

    INFO("[evpq_test] connected");

    12

    13

    if (evpq_query(conn, QUERY_DEFAULT))

    14

        FATAL("evpq_query");

    15

}

    16

    17

void cb_result (struct evpq_conn *conn, PGresult *result, void *arg) {

    18

    19

    INFO("[evpq_test] result: %s", PQresStatus(PQresultStatus(result)));

    20

    21

    // fatal error?

    22

    if (PQresultStatus(result) != PGRES_TUPLES_OK)

    23

        FATAL("error: %s", PQresultErrorMessage(result));

    24

    25

    // dump it to stdout

    26

    PQprintOpt popt = {

    27

        .header     = 1,

    28

        .align      = 1,

    29

        .standard   = 0,

    30

        .html3      = 0,

    31

        .expanded   = 1,

    32

        .pager      = 0,

    33

        .fieldSep   = "|",

    34

        .tableOpt   = NULL,

    35

        .caption    = NULL,

    36

        .fieldName  = NULL,

    37

    };

    38

    39

    PQprint(stdout, result, &popt);

    40

    41

    // don't care about the result anymore

    42

    PQclear(result);

    43

}

    44

    45

void cb_done (struct evpq_conn *conn, void *arg) {

    46

    INFO("[evpq_test] done");

    47

}

    48

    49

void cb_failure (struct evpq_conn *conn, void *arg) {

    50

    INFO("[evpq_test] failure");

    51

    INFO("\t%s", evpq_error_message(conn));

    52

    53

    FATAL("exiting");

    54

}

    55

    56

int main (int argc, char **argv) {

    57

    struct event_base *ev_base = NULL;

    58

    struct evpq_conn *conn = NULL;

    59

    const char *conninfo = CONNINFO_DEFAULT;

    60

    61

    struct evpq_callback_info cb_info = {

    62

        .fn_connected = cb_connected,

    63

        .fn_result = cb_result,

    64

        .fn_done = cb_done,

    65

        .fn_failure = cb_failure,

    66

    };

    67

    68

    // initialize libevent

    69

    if ((ev_base = event_base_new()) == NULL)

    70

        ERROR("event_base_new");

    71

    72

    // establish the evpq connection

    73

    if ((conn = evpq_connect(ev_base, conninfo, cb_info, NULL)) == NULL)

    74

        ERROR("evpq_connect");

    75

    76

    // run libevent

    77

    INFO("running libevent loop");

    78

    79

    if (event_base_dispatch(ev_base))

    80

        ERROR("event_base_dispatch");

    81

    82

    // clean shutdown

    83

    84

error:

    85

    if (ev_base)

    86

        event_base_free(ev_base);

    87

}

    88

    89