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);
}
int sx_set(sx *x, sxindex *index, svv *version)
{
sxmanager *m = x->manager;
sr *r = m->r;
if (! (version->flags & SVGET)) {
x->log_read = -1;
}
/* allocate mvcc container */
sxv *v = sx_valloc(m->asxv, version);
if (ssunlikely(v == NULL)) {
ss_quota(r->quota, SS_QREMOVE, sv_vsize(version));
sv_vfree(r, version);
return -1;
}
v->id = x->id;
v->index = index;
svlogv lv;
lv.id = index->dsn;
lv.next = UINT32_MAX;
sv_init(&lv.v, &sx_vif, v, NULL);
/* update concurrent index */
ssrbnode *n = NULL;
int rc = sx_match(&index->i, index->r->scheme,
sv_vpointer(version),
version->size,
&n);
if (ssunlikely(rc == 0 && n)) {
/* exists */
} else {
int pos = rc;
/* unique */
v->lo = sv_logcount(&x->log);
rc = sv_logadd(&x->log, r->a, &lv, index->ptr);
if (ssunlikely(rc == -1)) {
sr_oom(r->e);
goto error;
}
ss_rbset(&index->i, n, pos, &v->node);
return 0;
}
sxv *head = sscast(n, sxv, node);
/* match previous update made by current
* transaction */
sxv *own = sx_vmatch(head, x->id);
if (ssunlikely(own))
{
if (ssunlikely(version->flags & SVUPDATE)) {
sr_error(r->e, "%s", "only one update statement is "
"allowed per a transaction key");
goto error;
}
/* replace old document with the new one */
lv.next = sv_logat(&x->log, own->lo)->next;
v->lo = own->lo;
if (ssunlikely(sx_vaborted(own)))
sx_vabort(v);
sx_vreplace(own, v);
if (sslikely(head == own))
ss_rbreplace(&index->i, &own->node, &v->node);
/* update log */
sv_logreplace(&x->log, v->lo, &lv);
ss_quota(r->quota, SS_QREMOVE, sv_vsize(own->v));
sx_vfree(r, m->asxv, own);
return 0;
}
/* update log */
v->lo = sv_logcount(&x->log);
rc = sv_logadd(&x->log, r->a, &lv, index->ptr);
if (ssunlikely(rc == -1)) {
sr_oom(r->e);
goto error;
}
/* add version */
sx_vlink(head, v);
return 0;
error:
ss_quota(r->quota, SS_QREMOVE, sv_vsize(v->v));
sx_vfree(r, m->asxv, v);
return -1;
}
int sx_set(sx *x, sxindex *index, svv *version)
{
sxmanager *m = x->manager;
sr *r = index->r;
svlogv lv;
lv.index_id = index->dsn;
lv.next = UINT32_MAX;
lv.v = version;
lv.ptr = NULL;
/* allocate mvcc container */
sxv *v = sx_valloc(&m->pool, version);
if (ssunlikely(v == NULL)) {
sv_vunref(r, version);
return -1;
}
v->id = x->id;
v->index = index;
lv.ptr = v;
if (! (sv_vflags(version, index->r) & SVGET))
x->log_read = -1;
/* update concurrent index */
ssrbnode *n = NULL;
int rc;
rc = sx_match(&index->i, index->r->scheme,
sv_vpointer(version), 0, &n);
if (ssunlikely(rc == 0 && n)) {
/* exists */
} else {
int pos = rc;
/* unique */
v->lo = sv_logcount(x->log);
rc = sv_logadd(x->log, r, &lv);
if (ssunlikely(rc == -1)) {
sr_oom(r->e);
goto error;
}
ss_rbset(&index->i, n, pos, &v->node);
return 0;
}
sxv *head = sscast(n, sxv, node);
/* match previous update made by current
* transaction */
sxv *own = sx_vmatch(head, x->id);
if (ssunlikely(own))
{
if (ssunlikely(sv_vflags(version, index->r) & SVUPSERT)) {
sr_error(r->e, "%s", "only one upsert statement is "
"allowed per a transaction key");
goto error;
}
/* replace old document with the new one */
lv.next = sv_logat(x->log, own->lo)->next;
v->lo = own->lo;
if (ssunlikely(sx_vaborted(own)))
sx_vabort(v);
sx_vreplace(own, v);
if (sslikely(head == own))
ss_rbreplace(&index->i, &own->node, &v->node);
/* update log */
sv_logreplace(x->log, r, v->lo, &lv);
sx_vfree(&m->pool, r, own);
return 0;
}
/* update log */
v->lo = sv_logcount(x->log);
rc = sv_logadd(x->log, r, &lv);
if (ssunlikely(rc == -1)) {
sr_oom(r->e);
goto error;
}
/* add version */
sx_vlink(head, v);
return 0;
error:
sx_vfree(&m->pool, r, v);
return -1;
}
