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

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---*/
#include <config.h>
#include <stasis/common.h>

#include <assert.h>
#include <string.h>
#include <stdio.h>

#include <stasis/operations.h>
#include <stasis/logger/logger2.h>
#include <stasis/bufferManager.h>

#include "page.h"


Operation operationsTable[MAX_OPERATIONS];

/**
   @todo operations.c should handle LSN's for non-logical operations.
*/
void doUpdate(const LogEntry * e, Page * p) {
  DEBUG("OPERATION update arg length %d, lsn = %ld\n",
	e->contents.update.argSize, e->LSN);

  operationsTable[e->update.funcID].run(e->xid, p, e->LSN, 
					e->update.rid, getUpdateArgs(e));
}

void redoUpdate(const LogEntry * e) {
  if(e->type == UPDATELOG) {
    recordid rid = e->update.rid;
    Page * p;
    lsn_t pageLSN;
    try {
      if(operationsTable[e->update.funcID].sizeofData == SIZEIS_PAGEID) {
	p = NULL;
	pageLSN = 0;
      } else {
	p = loadPage(e->xid, rid.page);
	pageLSN = stasis_page_lsn_read(p);
      } 
    } end;

    if(e->LSN > pageLSN) {
      DEBUG("OPERATION Redo, %ld > %ld {%d %d %ld}\n",
	    e->LSN, pageLSN, rid.page, rid.slot, rid.size);
      // Need to check the id field to find out what the _REDO_ action
      // is for this log type.  contrast with doUpdate(), which
      // doesn't use the .id field.
      operationsTable[operationsTable[e->update.funcID].id]
	.run(e->xid, p, e->LSN, e->update.rid, getUpdateArgs(e));

    } else {
      DEBUG("OPERATION Skipping redo, %ld <= %ld {%d %d %ld}\n",
	    e->LSN, pageLSN, rid.page, rid.slot, rid.size);
    }
    if(p) { 
      releasePage(p);
    }
  } else if(e->type == CLRLOG) {
    recordid rid = e->update.rid;
    Page * p = NULL;
    lsn_t pageLSN;
    
    int isNullRid = !memcmp(&rid, &NULLRID, sizeof(recordid));
    if(!isNullRid) {
      if(operationsTable[e->update.funcID].sizeofData == SIZEIS_PAGEID) {
	p = NULL;
	pageLSN = 0;
      } else { 
	try { 
	  p = loadPage(e->xid, rid.page);
	  pageLSN = stasis_page_lsn_read(p);
	} end;
      }
    }
      
      /* See if the page contains the result of the undo that this CLR
	 is supposed to perform. If it doesn't, or this was a logical
	 operation, then undo the original operation. */
      
      
    if(isNullRid || e->LSN > pageLSN) {
      
      DEBUG("OPERATION Undoing for clr, %ld {%d %d %ld}\n", 
	    e->LSN, rid.page, rid.slot, rid.size);
      undoUpdate(e, p, e->LSN);
    } else {
      DEBUG("OPERATION Skiping undo for clr, %ld {%d %d %ld}\n", 
	    e->LSN, rid.page, rid.slot, rid.size);
    }
    if(p) { 
      releasePage(p);
    }
  } else {
    abort();
  }
}


void undoUpdate(const LogEntry * e, Page * p, lsn_t clr_lsn) {

  int undo = operationsTable[e->update.funcID].undo;
  DEBUG("OPERATION FuncID %d Undo op %d LSN %ld\n",
	e->update.funcID, undo, clr_lsn);

#ifdef DEBUGGING
  recordid rid = e->update.rid;
#endif
  lsn_t page_lsn = -1;
  if(p) {
    page_lsn = stasis_page_lsn_read(p);
  }
  if(e->LSN <= page_lsn || !p) {
    // Actually execute the undo 
    if(undo == NO_INVERSE) {

      DEBUG("OPERATION %d Physical undo, %ld {%d %d %ld}\n", undo, e->LSN, 
	    e->update.rid.page, e->contents.rid.slot, e->update.rid.size);

      assert(p);  
      stasis_record_write(e->xid, p, clr_lsn, e->update.rid, getUpdatePreImage(e));

    } else if(undo == NO_INVERSE_WHOLE_PAGE) {

      DEBUG("OPERATION %d Whole page physical undo, %ld {%d}\n", undo, e->LSN,
	    e->update.rid.page);

      assert(p);
      memcpy(p->memAddr, getUpdatePreImage(e), PAGE_SIZE);
      stasis_page_lsn_write(e->xid, p, clr_lsn);

    } else {

      DEBUG("OPERATION %d Logical undo, %ld {%d %d %ld}\n", undo, e->LSN, 
	    e->update.rid.page, e->update.rid.slot, e->update.rid.size);

      operationsTable[undo].run(e->xid, p, clr_lsn, e->update.rid, 
				getUpdateArgs(e));
    }
  } else {
    DEBUG("OPERATION %d Skipping undo, %ld {%d %d %ld}\n", undo, e->LSN, 
	  e->update.rid.page, e->update.rid.slot, e->update.rid.size);
  }
}