1 #ifndef EVSQL_INTERNAL_H

     2 #define EVSQL_INTERNAL_H

     3 

     4 /*

     5  * Internal interfaces

     6  */

     7 

     8 #include <sys/queue.h>

     9 

    10 #include <event2/event.h>

    11 

    12 #include "../evsql.h"

    13 #include "../evpq.h"

    14 

    15 /*

    16  * The engine type

    17  */

    18 enum evsql_type {

    19     EVSQL_EVPQ,     // evpq

    20 };

    21 

    22 /*

    23  * Contains the type, engine configuration, list of connections and waiting query queue.

    24  */

    25 struct evsql {

    26     // what event_base to use

    27     struct event_base *ev_base;

    28 

    29     // what engine we use

    30     enum evsql_type type;

    31 

    32     // callbacks

    33     evsql_error_cb error_fn;

    34     void *cb_arg;

    35     

    36     // engine-specific connection configuration

    37     union {

    38         const char *evpq;

    39     } engine_conf;

    40 

    41     // list of connections that are open

    42     LIST_HEAD(evsql_conn_list, evsql_conn) conn_list;

    43    

    44     // list of queries running or waiting to run

    45     TAILQ_HEAD(evsql_query_queue, evsql_query) query_queue;

    46 };

    47 

    48 /*

    49  * A single connection to the server.

    50  *

    51  * Contains the engine connection, may have a transaction associated, and may have a query associated.

    52  */

    53 struct evsql_conn {

    54     // evsql we belong to

    55     struct evsql *evsql;

    56 

    57     // engine-specific connection info

    58     union {

    59         struct evpq_conn *evpq;

    60     } engine;

    61 

    62     // our position in the conn list

    63     LIST_ENTRY(evsql_conn) entry;

    64 

    65     // are we running a transaction?

    66     struct evsql_trans *trans;

    67 

    68     // are we running a transactionless query?

    69     struct evsql_query *query;

    70 };

    71 

    72 /*

    73  * A single transaction.

    74  *

    75  * Has a connection associated and possibly a query (which will also be associated with the connection)

    76  */

    77 struct evsql_trans {

    78     // our evsql_conn/evsql

    79     struct evsql *evsql;

    80     struct evsql_conn *conn;

    81     

    82     // callbacks

    83     evsql_trans_error_cb error_fn;

    84     evsql_trans_ready_cb ready_fn;

    85     evsql_trans_done_cb done_fn;

    86     void *cb_arg;

    87 

    88     // the transaction type

    89     enum evsql_trans_type type;

    90 

    91     // has evsql_trans_commit be called?

    92     int has_commit : 1;

    93 

    94     // our current query

    95     struct evsql_query *query;

    96 

    97 };

    98 

    99 /*

   100  * A single query.

   101  *

   102  * Has the info needed to exec the query (as these may be queued), and the callback/result info.

   103  */

   104 struct evsql_query {

   105     // the actual SQL query, this may or may not be ours, see _evsql_query_exec

   106     char *command;

   107     

   108     // possible query params

   109     struct evsql_query_param_info {

   110         int count;

   111 

   112         Oid *types;

   113         const char **values;

   114         int *lengths;

   115         int *formats;

   116 

   117         int result_format;

   118     } params;

   119 

   120     // our callback

   121     evsql_query_cb cb_fn;

   122     void *cb_arg;

   123 

   124     // our position in the query list

   125     TAILQ_ENTRY(evsql_query) entry;

   126 

   127     // the result

   128     union {

   129         PGresult *evpq;

   130     } result;

   131 };

   132 

   133 // maximum length for a 'BEGIN TRANSACTION ...' query

   134 #define EVSQL_QUERY_BEGIN_BUF 512

   135 

   136 #endif /* EVSQL_INTERNAL_H */