stasis-aries-wal/src/lladd/operations/prepare.c

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/**********************************************
 * $Id$
 * 
 * sets the given reference to dat
 **********************************************/

#include <lladd/operations/prepare.h>
/*#include "../logger/logstreamer.h"*/
#include <lladd/logger/logWriter.h>
#include <malloc.h>

recordid prepare_bogus_rec  = { 0, 0, 0};

static int operate(int xid, recordid rid, const void *dat) {
  syncLog();
  return 0;
}
/*static int no_op(int xid, recordid rid, const void *dat) {
  return 0;
  }*/

/**
   Tprepare notes:

   - Just a Tupdate, with a log flush as its operationsTable[]
     function. (done)

   - After recovery, all of the xacts pages will have been 'stolen',
     (if recovery flushes dirty pages) (done)

   - Recovery function needs to distinguish between actions before and
     after the last Tprepare log entry.
     
   - The switch in recovUndo needs to treat Tprepares as follows:

     - If we're really doing recovery, don't push the prevLSN onto
       transRecLSN's.  Instead, add it to the active transaction table
       in transactional.c

     - If not, do nothing, but push the prevLSN onto transRecLSN's

*/

Operation getPrepare() { 
	Operation o = {
		OPERATION_PREPARE, /* id */
		0, /* No extra data. */
		OPERATION_PREPARE, /*&no_op,*/ /* Otherwise, it will need to store a pre-image of something... */
		&operate /* Function */
	};
	return o;
}

/** PrepareGuardState is 1 if the iterator should continue on the next
    (previous) log entry, 0 otherwise. */
typedef int PrepareGuardState;

void * getPrepareGuardState() { 
  PrepareGuardState * s = malloc (sizeof(PrepareGuardState));
  *s = 1;
  return s;
}


int prepareGuard(LogEntry * e, void * state) {
  PrepareGuardState * pgs = state; 
  int ret = *pgs;
  if(e->type == UPDATELOG) {
    if(e->contents.update.funcID == OPERATION_PREPARE) { 
      *pgs = 0;
    }
  }
  return ret;
}