src/include/replication/walreceiver.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * walreceiver.h
   4  *        Exports from replication/walreceiverfuncs.c.
   5  *
   6  * Portions Copyright (c) 2010-2010, PostgreSQL Global Development Group
   7  *
   8  * $PostgreSQL: pgsql/src/include/replication/walreceiver.h,v 1.1 2010/01/15 09:19:09 heikki Exp $
   9  *
  10  *-------------------------------------------------------------------------
  11  */
  12 #ifndef _WALRECEIVER_H
  13 #define _WALRECEIVER_H
  14
  15 #include "storage/spin.h"
  16
  17 /*
  18  * MAXCONNINFO: maximum size of a connection string.
  19  *
  20  * XXX: Should this move to pg_config_manual.h?
  21  */
  22 #define MAXCONNINFO             1024
  23
  24 /*
  25  * Values for WalRcv->walRcvState.
  26  */
  27 typedef enum
  28 {
  29         WALRCV_NOT_STARTED,
  30         WALRCV_RUNNING,         /* walreceiver has been started */
  31         WALRCV_STOPPING,        /* requested to stop, but still running */
  32         WALRCV_STOPPED          /* stopped and mustn't start up again */
  33 } WalRcvState;
  34
  35 /* Shared memory area for management of walreceiver process */
  36 typedef struct
  37 {
  38         /*
  39          * connection string; is used for walreceiver to connect with
  40          * the primary.
  41          */
  42         char    conninfo[MAXCONNINFO];
  43
  44         /*
  45          * PID of currently active walreceiver process, and the current state.
  46          */
  47         pid_t   pid;
  48         WalRcvState walRcvState;
  49
  50         /*
  51          * receivedUpto-1 is the last byte position that has been already
  52          * received. When startup process starts the walreceiver, it sets this
  53          * to the point where it wants the streaming to begin. After that,
  54          * walreceiver updates this whenever it flushes the received WAL.
  55          */
  56         XLogRecPtr      receivedUpto;
  57
  58         slock_t mutex;          /* locks shared variables shown above */
  59 } WalRcvData;
  60
  61 extern WalRcvData *WalRcv;
  62
  63 extern Size WalRcvShmemSize(void);
  64 extern void WalRcvShmemInit(void);
  65 extern bool WalRcvInProgress(void);
  66 extern XLogRecPtr WaitNextXLogAvailable(XLogRecPtr recptr, bool *finished);
  67 extern void RequestXLogStreaming(XLogRecPtr recptr, const char *conninfo);
  68 extern XLogRecPtr GetWalRcvWriteRecPtr(void);
  69
  70 #endif   /* _WALRECEIVER_H */