sxstate sx_prepare(sx *x, sxpreparef prepare, void *arg)
{
uint64_t lsn = sr_seq(x->manager->seq, SR_LSN);
/* proceed read-only transactions */
if (x->type == SX_RO || sv_logcount_write(x->log) == 0)
return sx_promote(x, SX_PREPARE);
ssiter i;
ss_iterinit(ss_bufiter, &i);
ss_iteropen(ss_bufiter, &i, &x->log->buf, sizeof(svlogv));
sxstate rc;
for (; ss_iterhas(ss_bufiter, &i); ss_iternext(ss_bufiter, &i))
{
svlogv *lv = ss_iterof(ss_bufiter, &i);
sxv *v = lv->ptr;
if ((int)v->lo == x->log_read)
break;
if (sx_vaborted(v))
return sx_promote(x, SX_ROLLBACK);
if (sslikely(v->prev == NULL)) {
rc = sx_preparecb(x, lv, lsn, prepare, arg);
if (ssunlikely(rc != 0))
return sx_promote(x, SX_ROLLBACK);
continue;
}
if (sx_vcommitted(v->prev)) {
if (v->prev->csn > x->csn)
return sx_promote(x, SX_ROLLBACK);
continue;
}
/* force commit for read-only conflicts */
sxindex *i = v->prev->index;
if (sv_vflags(v->prev->v, i->r) & SVGET) {
rc = sx_preparecb(x, lv, lsn, prepare, arg);
if (ssunlikely(rc != 0))
return sx_promote(x, SX_ROLLBACK);
continue;
}
return sx_promote(x, SX_LOCK);
}
return sx_promote(x, SX_PREPARE);
}
sxstate sx_prepare(sx *x, sxpreparef prepare, void *arg)
{
uint64_t lsn = sr_seq(x->manager->r->seq, SR_LSN);
/* proceed read-only transactions */
if (x->type == SXRO || sv_logcount_write(&x->log) == 0)
return sx_promote(x, SXPREPARE);
ssiter i;
ss_iterinit(ss_bufiter, &i);
ss_iteropen(ss_bufiter, &i, &x->log.buf, sizeof(svlogv));
for (; ss_iterhas(ss_bufiter, &i); ss_iternext(ss_bufiter, &i))
{
svlogv *lv = ss_iterof(ss_bufiter, &i);
sxv *v = lv->v.v;
if ((int)v->lo == x->log_read)
break;
if (sx_vaborted(v))
return sx_promote(x, SXROLLBACK);
if (sslikely(v->prev == NULL)) {
if (prepare && lsn != x->vlsn) {
sxindex *i = v->index;
if (prepare(x, &lv->v, arg, i->ptr))
return sx_promote(x, SXROLLBACK);
}
continue;
}
if (sx_vcommitted(v->prev)) {
if (v->prev->csn > x->csn)
return sx_promote(x, SXROLLBACK);
continue;
}
/* force commit for read-only conflicts */
if (v->prev->v->flags & SVGET)
continue;
return sx_promote(x, SXLOCK);
}
return sx_promote(x, SXPREPARE);
}
