src/include/fe_utils/parallel_slot.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  *      parallel_slot.h
   4  *              Parallel support for bin/scripts/
   5  *
   6  *      Copyright (c) 2003-2024, PostgreSQL Global Development Group
   7  *
   8  *      src/include/fe_utils/parallel_slot.h
   9  *
  10  *-------------------------------------------------------------------------
  11  */
  12 #ifndef PARALLEL_SLOT_H
  13 #define PARALLEL_SLOT_H
  14
  15 #include "fe_utils/connect_utils.h"
  16 #include "libpq-fe.h"
  17
  18 typedef bool (*ParallelSlotResultHandler) (PGresult *res, PGconn *conn,
  19                                                                                    void *context);
  20
  21 typedef struct ParallelSlot
  22 {
  23         PGconn     *connection;         /* One connection */
  24         bool            inUse;                  /* Is the slot being used? */
  25
  26         /*
  27          * Prior to issuing a command or query on 'connection', a handler callback
  28          * function may optionally be registered to be invoked to process the
  29          * results, and context information may optionally be registered for use
  30          * by the handler.  If unset, these fields should be NULL.
  31          */
  32         ParallelSlotResultHandler handler;
  33         void       *handler_context;
  34 } ParallelSlot;
  35
  36 typedef struct ParallelSlotArray
  37 {
  38         int                     numslots;
  39         ConnParams *cparams;
  40         const char *progname;
  41         bool            echo;
  42         const char *initcmd;
  43         ParallelSlot slots[FLEXIBLE_ARRAY_MEMBER];
  44 } ParallelSlotArray;
  45
  46 static inline void
  47 ParallelSlotSetHandler(ParallelSlot *slot, ParallelSlotResultHandler handler,
  48                                            void *context)
  49 {
  50         slot->handler = handler;
  51         slot->handler_context = context;
  52 }
  53
  54 static inline void
  55 ParallelSlotClearHandler(ParallelSlot *slot)
  56 {
  57         slot->handler = NULL;
  58         slot->handler_context = NULL;
  59 }
  60
  61 extern ParallelSlot *ParallelSlotsGetIdle(ParallelSlotArray *sa,
  62                                                                                   const char *dbname);
  63
  64 extern ParallelSlotArray *ParallelSlotsSetup(int numslots, ConnParams *cparams,
  65                                                                                          const char *progname, bool echo,
  66                                                                                          const char *initcmd);
  67
  68 extern void ParallelSlotsAdoptConn(ParallelSlotArray *sa, PGconn *conn);
  69
  70 extern void ParallelSlotsTerminate(ParallelSlotArray *sa);
  71
  72 extern bool ParallelSlotsWaitCompletion(ParallelSlotArray *sa);
  73
  74 extern bool TableCommandResultHandler(PGresult *res, PGconn *conn,
  75                                                                           void *context);
  76
  77 #endif                                                  /* PARALLEL_SLOT_H */