/* Read a page from the write-ahead log, if it is present. */
int sqlite3WalFindFrame(Wal *pWal, Pgno pgno, u32 *piRead)
{
// db_thread * const thread = enif_tsd_get(g_tsd_thread);
#if ATOMIC
db_thread *thread = g_tsd_thread;
#else
db_thread* thread = enif_tsd_get(g_tsd_thread);
#endif
/*if (thr->isreadonly)
{
u64 readSafeEvnum, readSafeTerm;
#ifndef _TESTAPP_
enif_mutex_lock(pWal->mtx);
#endif
readSafeEvnum = pWal->rthread->readSafeEvnum;
readSafeTerm = pWal->rthread->readSafeTerm;
#ifndef _TESTAPP_
enif_mutex_unlock(pWal->mtx);
#endif
return findframe(pWal->rthread, pWal, pgno, piRead, readSafeTerm, readSafeEvnum, NULL, NULL);
}
else*/ if (pWal->inProgressTerm > 0 || pWal->inProgressEvnum > 0)
return findframe(thread, pWal, pgno, piRead, pWal->inProgressTerm,
pWal->inProgressEvnum, NULL, NULL);
else
return findframe(thread, pWal, pgno, piRead, pWal->lastCompleteTerm,
pWal->lastCompleteEvnum, NULL, NULL);
}
int
main(int argc, char *argv[]) {
char *s;
fmtinstall('r', errfmt);
extern int fmtevent(Fmt*);
fmtinstall('E', fmtevent);
ARGBEGIN{
default:
usage();
}ARGEND;
s = EARGF(usage());
if(!getulong(s, &win.xid))
usage();
if(argc)
usage();
setlocale(LC_CTYPE, "");
initdisplay();
frame = findframe(&win);
getwinsize(&frame);
restrut();
sethandler(&frame, &handlers);
selectinput(&frame, StructureNotifyMask);
running = true;
xevent_loop();
XCloseDisplay(display);
return 0;
}
// return number of bytes written
static int wal_iterate(Wal *pWal, iterate_resource *iter, u8 *buf, int bufsize, u8 *hdr, u32 *done)
{
// db_thread* const thr = enif_tsd_get(g_tsd_thread);
#if ATOMIC
db_thread *thr = g_tsd_thread;
#else
db_thread* thr = enif_tsd_get(g_tsd_thread);
#endif
mdbinf* const mdb = &thr->mdb;
u32 mxPage;
u64 readSafeEvnum, readSafeTerm;
#ifndef _TESTAPP_
enif_mutex_lock(pWal->mtx);
#endif
readSafeEvnum = pWal->lastCompleteEvnum;
readSafeTerm = pWal->lastCompleteTerm;
mxPage = pWal->mxPage;
#ifndef _TESTAPP_
enif_mutex_unlock(pWal->mtx);
#endif
if (!iter->started)
{
if (iter->evnum + iter->evterm == 0)
{
// If any writes come after iterator started, we must ignore those pages.
iter->evnum = readSafeEvnum;
iter->evterm = readSafeTerm;
iter->pgnoPos = 1;
iter->entiredb = 1;
iter->mxPage = mxPage;
if (pWal->mxPage == 0)
{
DBG("ERROR: Iterate on empty DB %llu",pWal->lastCompleteEvnum);
*done = 1;
return 0;
}
}
else
{
// set mxPage to highest pgno we find.
iter->pgnoPos = iter->mxPage = 0;
DBG("Iterate rsterm=%llu rsevnum=%llu",readSafeTerm,readSafeEvnum);
}
iter->started = 1;
}
// send entire db (without history)
if (iter->entiredb)
{
u32 iRead = 0;
findframe(thr, pWal, iter->pgnoPos, &iRead, iter->evterm, iter->evnum, NULL, NULL);
if (!iRead)
{
DBG("Iterate did not find page");
*done = iter->mxPage;
return 0;
}
DBG("Iter pos=%u, mx=%u, safemx=%u",iter->pgnoPos, iter->mxPage, mxPage);
if (iter->pgnoPos == iter->mxPage)
*done = iter->mxPage;
put8byte(hdr, iter->evterm);
put8byte(hdr+sizeof(u64), iter->evnum);
put4byte(hdr+sizeof(u64)*2, iter->pgnoPos);
put4byte(hdr+sizeof(u64)*2+sizeof(u32), *done);
iter->pgnoPos++;
return fillbuff(thr, pWal, iter, buf, bufsize);
}
else
{
MDB_val logKey, logVal;
int logop;
u8 logKeyBuf[sizeof(u64)*3];
int rc;
// ** - Log DB: {<<ActorIndex:64, Evterm:64, Evnum:64>>, <<Pgno:32/unsigned>>}
memcpy(logKeyBuf, &pWal->index, sizeof(u64));
memcpy(logKeyBuf + sizeof(u64), &iter->evterm, sizeof(u64));
memcpy(logKeyBuf + sizeof(u64)*2, &iter->evnum, sizeof(u64));
logKey.mv_data = logKeyBuf;
logKey.mv_size = sizeof(logKeyBuf);
DBG("iterate looking for, matchterm=%llu matchevnum=%llu",iter->evterm,iter->evnum);
if (mdb_cursor_get(mdb->cursorLog,&logKey,&logVal,MDB_SET) != MDB_SUCCESS)
{
// Evterm/evnum combination not found. Check if evnum is there.
// If so return evterm. It will mean a node is in conflict.
DBG("Key not found in log");
if (readSafeEvnum == iter->evnum)
{
iter->evterm = readSafeTerm;
iter->termMismatch = 1;
}
else
{
memcpy(logKeyBuf, &pWal->index, sizeof(u64));
memcpy(logKeyBuf + sizeof(u64), &readSafeTerm, sizeof(u64));
memcpy(logKeyBuf + sizeof(u64)*2, &readSafeEvnum,sizeof(u64));
if (mdb_cursor_get(mdb->cursorLog,&logKey,&logVal,MDB_SET) != MDB_SUCCESS)
{
DBG("Key not found in log for undo");
*done = 1;
return 0;
}
while (mdb_cursor_get(mdb->cursorLog,&logKey,&logVal,MDB_PREV_NODUP) == MDB_SUCCESS)
{
u64 aindex, term, evnum;
mdb_cursor_get(mdb->cursorLog,&logKey, &logVal, MDB_GET_CURRENT);
memcpy(&aindex, logKey.mv_data, sizeof(u64));
memcpy(&term, (u8*)logKey.mv_data+sizeof(u64), sizeof(u64));
memcpy(&evnum, (u8*)logKey.mv_data+sizeof(u64)*2,sizeof(u64));
DBG("Iterate on term=%llu, evnum=%llu, looking for=%llu",term,evnum,iter->evnum);
if (aindex != pWal->index)
break;
if (iter->evnum == evnum)
{
iter->evterm = term;
iter->termMismatch = 1;
break;
}
}
}
*done = 1;
return 0;
}
// We start iterate from next evnum not current. Input evterm/evnum is match_index and match_term.
// It needs next.
if (iter->started == 1 &&
(rc = mdb_cursor_get(mdb->cursorLog,&logKey, &logVal, MDB_NEXT_NODUP)) != MDB_SUCCESS)
{
*done = 1;
return 0;
}
else
{
u64 aindex;
rc = mdb_cursor_get(mdb->cursorLog,&logKey, &logVal, MDB_GET_CURRENT);
if (rc != MDB_SUCCESS)
{
*done = 1;
return 0;
}
memcpy(&aindex, (u8*)logKey.mv_data, sizeof(u64));
memcpy(&iter->evterm, (u8*)logKey.mv_data+sizeof(u64), sizeof(u64));
memcpy(&iter->evnum, (u8*)logKey.mv_data+sizeof(u64)*2,sizeof(u64));
if (aindex != pWal->index)
{
*done = 1;
return 0;
}
// To keep from moving iter->evterm/iter->evnum forward more than once.
iter->started = 2;
}
logop = MDB_FIRST_DUP;
while ((rc = mdb_cursor_get(mdb->cursorLog,&logKey,&logVal,logop)) == MDB_SUCCESS)
{
u64 evnum,evterm;
u32 pgno;
u32 iRead;
logop = MDB_NEXT_DUP;
mdb_cursor_get(mdb->cursorLog,&logKey, &logVal, MDB_GET_CURRENT);
memcpy(&pgno,logVal.mv_data,sizeof(u32));
DBG("iterate at pgno=%u, pgnopos=%u",pgno,iter->pgnoPos);
if (pgno <= iter->pgnoPos)
continue;
findframe(thr, pWal, pgno, &iRead, iter->evterm, iter->evnum, &evterm, &evnum);
if (iRead == 0)
{
DBG("ERROR: Did not find frame for pgno=%u, evterm=%llu, evnum=%llu",
pgno, iter->evterm, iter->evnum);
*done = 1;
return 0;
}
if (evterm != iter->evterm || evnum != iter->evnum)
{
DBG("ERROR: Evterm/evnum does not match,looking for: evterm=%llu, evnum=%llu, "
"got: evterm=%llu, evnum=%llu", iter->evterm, iter->evnum, evterm, evnum);
*done = 1;
return 0;
}
iter->pgnoPos = pgno;
if ((rc = mdb_cursor_get(mdb->cursorLog,&logKey,&logVal,logop)) == MDB_SUCCESS)
*done = 0;
else
*done = iter->pgnoPos;
DBG( "logcursor get next %d, done=%u",rc,*done);
put8byte(hdr, iter->evterm);
put8byte(hdr+sizeof(u64), iter->evnum);
put4byte(hdr+sizeof(u64)*2, iter->pgnoPos);
put4byte(hdr+sizeof(u64)*2+sizeof(u32), *done);
return fillbuff(thr, pWal, iter, buf, bufsize);
}
*done = 1;
return 0;
}
}
