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#ifndef EVSQL_H

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#define EVSQL_H

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/*

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

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 */

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// XXX: libpq

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#include <postgresql/libpq-fe.h>

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#include <event2/event.h>

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/*

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 * The generic context handle

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 */

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struct evsql;

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/*

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 * A query handle

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 */

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struct evsql_query;

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/*

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 * Query parameter info

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 * /

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struct evsql_query_params {

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    int count;

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    const char * const *values;

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    const int *lengths;

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    const int *formats;

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    int result_format;

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}; */

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/*

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 * Result type

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 */

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struct evsql_result_info {

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    struct evsql *evsql;

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    int error;

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    union {

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        // XXX: libpq

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        PGresult *pq;

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    } result;

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};

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/*

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 * Callback for handling query-level errors.

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 *

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

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

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 */

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

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/*

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 * Callback for handling connection-level errors.

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 *

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

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 */

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

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/*

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

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 */

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

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/*

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 * Queue the given query for execution.

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 */

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

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/*

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

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 *

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 * XXX: not implemented yet.

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 */

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void evsql_close (struct evsql *evsql);

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#endif /* EVSQL_H */