// RLock readlock resurs from thread
// uses double check
func (t *TControl) RLock(threadId uint16, resursId string) {
var wlock *string
for {
wlock = (*string)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&t.writer))))
if wlock == nil || *wlock != resursId {
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&t.readers[threadId])), unsafe.Pointer(&resursId))
wlock = (*string)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&t.writer))))
if wlock == nil || *wlock != resursId {
return
}
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&t.readers[threadId])), nil)
}
t.sleep()
}
}
func (b *Bucket) Refresh() error {
pool := b.pool
tmpb := &Bucket{}
err := pool.client.parseURLResponse(b.URI, tmpb)
if err != nil {
return err
}
newcps := make([]*connectionPool, len(tmpb.VBSMJson.ServerList))
for i := range newcps {
if b.ah != nil {
newcps[i] = newConnectionPool(
tmpb.VBSMJson.ServerList[i],
b.ah, PoolSize, PoolOverflow)
} else {
newcps[i] = newConnectionPool(
tmpb.VBSMJson.ServerList[i],
b.authHandler(), PoolSize, PoolOverflow)
}
}
b.replaceConnPools(newcps)
tmpb.ah = b.ah
atomic.StorePointer(&b.vBucketServerMap, unsafe.Pointer(&tmpb.VBSMJson))
atomic.StorePointer(&b.nodeList, unsafe.Pointer(&tmpb.NodesJSON))
return nil
}
func (p *partitionstore) visitItems(start []byte, withValue bool,
visitor func(*item) bool) (err error) {
keys, changes := p.colls()
var vErr error
v := func(kItem *gkvlite.Item) bool {
i := (*item)(atomic.LoadPointer(&kItem.Transient))
if i != nil {
return visitor(i)
}
var cItem *gkvlite.Item
cItem, vErr = changes.GetItem(kItem.Val, true)
if vErr != nil {
return false
}
if cItem == nil {
return true // TODO: track this case; might have been compacted away.
}
i = (*item)(atomic.LoadPointer(&cItem.Transient))
if i != nil {
atomic.StorePointer(&kItem.Transient, unsafe.Pointer(i))
return visitor(i)
}
i = &item{key: kItem.Key}
if vErr = i.fromValueBytes(cItem.Val); vErr != nil {
return false
}
atomic.StorePointer(&cItem.Transient, unsafe.Pointer(i))
atomic.StorePointer(&kItem.Transient, unsafe.Pointer(i))
return visitor(i)
}
if err := p.visit(keys, start, true, v); err != nil {
return err
}
return vErr
}
// Set background error.
func (d *DB) seterr(err error) {
if err == nil {
atomic.StorePointer(&d.err, nil)
} else {
atomic.StorePointer(&d.err, unsafe.Pointer(&errWrap{err}))
}
}
func (nloc *nodeLoc) Copy(src *nodeLoc) *nodeLoc {
if src == nil {
return nloc.Copy(empty_nodeLoc)
}
atomic.StorePointer(&nloc.loc, unsafe.Pointer(src.Loc()))
atomic.StorePointer(&nloc.node, unsafe.Pointer(src.Node()))
return nloc
}
func (i *itemLoc) Copy(src *itemLoc) {
if src == nil {
i.Copy(empty_itemLoc)
return
}
atomic.StorePointer(&i.loc, unsafe.Pointer(src.Loc()))
atomic.StorePointer(&i.item, unsafe.Pointer(src.Item()))
}
func (p *partitionstore) collsPauseSwap(cb func() (keys, changes *gkvlite.Collection)) {
p.lock.Lock()
defer p.lock.Unlock()
k, c := cb()
// Update the changes first, so that readers see a key index that's older.
atomic.StorePointer(&p.changes, unsafe.Pointer(c))
atomic.StorePointer(&p.keys, unsafe.Pointer(k))
}
func TestAtomicPointer() {
b1 := &B{
B1: 3,
B2: "33",
}
atomic.StorePointer(&bp, unsafe.Pointer(b1))
fmt.Println(*((*B)(bp))) // {3 33}
// atomic.StorePointer(&unsafe.Pointer(b), unsafe.Pointer(b1)) // yonka_test\test_json.go:1472: cannot take the address of unsafe.Pointer(b)
b := &B{1, "11"}
p := unsafe.Pointer(b)
atomic.StorePointer(&p, unsafe.Pointer(b1))
fmt.Println(*((*B)(p))) // {3 33}
fmt.Println(*b) // {1 11}
}
func (db *DB) Preparex(query string) (stmt Stmt, err error) {
var m stmtCache
if p := (*stmtCache)(atomic.LoadPointer(&db.stmtCachePtr)); p != nil {
m = *p
if stmt = m[query]; stmt.Stmt != nil {
return
}
}
db.stmtCachePtrMutex.Lock()
defer db.stmtCachePtrMutex.Unlock()
if p := (*stmtCache)(atomic.LoadPointer(&db.stmtCachePtr)); p != nil {
m = *p
if stmt = m[query]; stmt.Stmt != nil {
return
}
}
stmtx, err := db.DB.Preparex(query)
if err != nil {
return
}
stmt = Stmt{Stmt: stmtx}
m2 := make(stmtCache, len(m)+1)
for k, v := range m {
m2[k] = v
}
m2[query] = stmt
atomic.StorePointer(&db.stmtCachePtr, unsafe.Pointer(&m2))
return
}
func (nloc *nodeLoc) write(o *Store) error {
if nloc != nil && nloc.Loc().isEmpty() {
node := nloc.Node()
if node == nil {
return nil
}
offset := atomic.LoadInt64(&o.size)
length := ploc_length + ploc_length + ploc_length + 8 + 8
b := make([]byte, length)
pos := 0
pos = node.item.Loc().write(b, pos)
pos = node.left.Loc().write(b, pos)
pos = node.right.Loc().write(b, pos)
binary.BigEndian.PutUint64(b[pos:pos+8], node.numNodes)
pos += 8
binary.BigEndian.PutUint64(b[pos:pos+8], node.numBytes)
pos += 8
if pos != length {
return fmt.Errorf("nodeLoc.write() pos: %v didn't match length: %v",
pos, length)
}
if _, err := o.file.WriteAt(b, offset); err != nil {
return err
}
atomic.StoreInt64(&o.size, offset+int64(length))
atomic.StorePointer(&nloc.loc,
unsafe.Pointer(&ploc{Offset: offset, Length: uint32(length)}))
}
return nil
}
func ParseConfig(cfg string) {
if cfg == "" {
log.Fatalln("config file not specified: use -c $filename")
}
if !file.IsExist(cfg) {
log.Fatalln("config file specified not found:", cfg)
}
ConfigFile = cfg
configContent, err := file.ToTrimString(cfg)
if err != nil {
log.Fatalln("read config file", cfg, "error:", err.Error())
}
var c GlobalConfig
err = json.Unmarshal([]byte(configContent), &c)
if err != nil {
log.Fatalln("parse config file", cfg, "error:", err.Error())
}
if c.Migrate.Enabled && len(c.Migrate.Cluster) == 0 {
c.Migrate.Enabled = false
}
// set config
atomic.StorePointer(&ptr, unsafe.Pointer(&c))
log.Println("g.ParseConfig ok, file", cfg)
}
func ReadFirst(b []byte, v interface{}) (read bool, total int, err error) {
var t unsafe.Pointer
var r *[2]marshal.Reader
if t = readerCache; t != nil {
if atomic.CompareAndSwapPointer(&readerCache, t, nil) {
r = (*[2]marshal.Reader)(t)
*r = [2]marshal.Reader{{Body: b}, {}}
goto Got
}
}
r = &[2]marshal.Reader{{Body: b}, {}}
Got:
total = r[0].IntUint32()
if total > 0 {
sz := r[0].IntUint32()
if r[0].Err == nil {
r[1].Body = r[0].Slice(sz + 4)
err = ReadRawTuple(&r[1], v)
read = true
} else {
err = r[0].Err
}
}
atomic.StorePointer(&readerCache, unsafe.Pointer(r))
return
}
func (m *SharedMap) SetValue(key KeyType, value ValType) {
m.writeLock.Lock()
defer m.writeLock.Unlock()
newCurrent := m.Copy()
(*newCurrent)[key] = value
atomic.StorePointer(&m.current, unsafe.Pointer(newCurrent))
}
// Reload certificate
func (c *certificate) reload() error {
keystoreBytes, err := ioutil.ReadFile(c.keystorePath)
if err != nil {
return err
}
pemBlocks, err := pkcs12.ToPEM(keystoreBytes, c.keystorePass)
if err != nil {
return err
}
var pemBytes []byte
for _, block := range pemBlocks {
pemBytes = append(pemBytes, pem.EncodeToMemory(block)...)
}
certAndKey, err := tls.X509KeyPair(pemBytes, pemBytes)
if err != nil {
return err
}
certAndKey.Leaf, err = x509.ParseCertificate(certAndKey.Certificate[0])
if err != nil {
return err
}
atomic.StorePointer(&c.cached, unsafe.Pointer(&certAndKey))
return nil
}
// helper function for subdivide()
//
// places all points in the tree in the appropriate quadrant,
// and clears the points of this tree.
func (q *LockfreeQuadtree) disperse2() {
for {
oldPoints := (*PointList)(atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&q.Points))))
if oldPoints == nil || oldPoints.Length == 0 {
break
}
newPoints := *oldPoints
p := *newPoints.First.Point
newPoints.First = newPoints.First.Next
newPoints.Length--
ok := atomic.CompareAndSwapPointer((*unsafe.Pointer)(unsafe.Pointer(&q.Points)), unsafe.Pointer(oldPoints), unsafe.Pointer(&newPoints))
if !ok {
continue
}
ok = q.Nw.Insert(&p) || q.Ne.Insert(&p) || q.Sw.Insert(&p) || q.Se.Insert(&p)
// debug
if !ok {
panic("quadtree contained a point outside boundary")
}
}
// we don't need to compare. We know it needs set at nil now; if someone else set it first, setting again doesn't hurt.
// this does need to be atomic, however. Else, Query() might read a pointer which was half-set to nil
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&q.Points)), nil)
}
func (s *bucketstore) compactSwapFile(bsf *bucketstorefile, compactPath string) error {
idx, ver, err := parseStoreFileName(filepath.Base(bsf.path), STORE_FILE_SUFFIX)
if err != nil {
return err
}
nextName := makeStoreFileName(idx, ver+1, STORE_FILE_SUFFIX)
nextPath := path.Join(filepath.Dir(bsf.path), nextName)
if err = os.Rename(compactPath, nextPath); err != nil {
return err
}
nextFile, err := fileService.OpenFile(nextPath, os.O_RDWR|os.O_CREATE)
if err != nil {
return err
}
nextBSF := NewBucketStoreFile(nextPath, nextFile, bsf.stats)
nextStore, err := gkvlite.NewStore(nextBSF)
if err != nil {
// TODO: Rollback the previous *.orig rename.
return err
}
nextBSF.store = nextStore
atomic.StorePointer(&s.bsf, unsafe.Pointer(nextBSF))
bsf.apply(func() {
bsf.purge = true // Mark the old file as purgable.
})
return nil
}
// Create new memdb and froze the old one; need external synchronization.
func (d *DB) newMem() (m *memdb.DB, err error) {
s := d.s
num := s.allocFileNum()
w, err := newJournalWriter(s.getJournalFile(num))
if err != nil {
s.reuseFileNum(num)
return
}
old := d.journal
d.journal = w
if old != nil {
old.close()
d.fjournal = old
}
d.fseq = d.seq
m = memdb.New(s.cmp)
mem := &memSet{cur: m}
if old := d.getMem_NB(); old != nil {
mem.froze = old.cur
}
atomic.StorePointer(&d.mem, unsafe.Pointer(mem))
return
}
// Commit is used to finalize this transaction.
// This is a noop for read transactions.
func (txn *Txn) Commit() {
// Noop for a read transaction
if !txn.write {
return
}
// Check if already aborted or committed
if txn.rootTxn == nil {
return
}
// Commit each sub-transaction scoped to (table, index)
for key, subTxn := range txn.modified {
path := indexPath(key.Table, key.Index)
final := subTxn.Commit()
txn.rootTxn.Insert(path, final)
}
// Update the root of the DB
newRoot := txn.rootTxn.Commit()
atomic.StorePointer(&txn.db.root, unsafe.Pointer(newRoot))
// Clear the txn
txn.rootTxn = nil
txn.modified = nil
// Release the writer lock since this is invalid
txn.db.writer.Unlock()
// Run the deferred functions, if any
for i := len(txn.after); i > 0; i-- {
fn := txn.after[i-1]
fn()
}
}
// Truncate drops all data in BoundedTable.
func (t *BoundedTable) Truncate() {
// just reset everything.
for i := int64(0); i < t.capacity; i++ {
atomic.StorePointer(&t.records[i], unsafe.Pointer(nil))
}
t.cursor = 0
}
// NewRange initializes the range using the given metadata.
func NewRange(desc *proto.RangeDescriptor, rm rangeManager) (*Range, error) {
r := &Range{
rm: rm,
cmdQ: NewCommandQueue(),
tsCache: NewTimestampCache(rm.Clock()),
respCache: NewResponseCache(desc.RaftID, rm.Engine()),
pendingCmds: map[cmdIDKey]*pendingCmd{},
}
r.setDescWithoutProcessUpdate(desc)
lastIndex, err := r.loadLastIndex()
if err != nil {
return nil, err
}
atomic.StoreUint64(&r.lastIndex, lastIndex)
appliedIndex, err := r.loadAppliedIndex(r.rm.Engine())
if err != nil {
return nil, err
}
atomic.StoreUint64(&r.appliedIndex, appliedIndex)
lease, err := loadLeaderLease(r.rm.Engine(), desc.RaftID)
if err != nil {
return nil, err
}
atomic.StorePointer(&r.lease, unsafe.Pointer(lease))
if r.stats, err = newRangeStats(desc.RaftID, rm.Engine()); err != nil {
return nil, err
}
return r, nil
}
// copyToGen returns a copy of this I-node copied to the given generation.
func (i *iNode) copyToGen(gen *generation, ctrie *ctrie) *iNode {
nin := &iNode{gen: gen}
main := gcasRead(i, ctrie)
atomic.StorePointer(
(*unsafe.Pointer)(unsafe.Pointer(&nin.main)), unsafe.Pointer(main))
return nin
}
// Load loads DLL file d.Name into memory. It returns an error if fails.
// Load will not try to load DLL, if it is already loaded into memory.
func (d *LazyDLL) Load() error {
// Non-racy version of:
// if d.dll != nil {
if atomic.LoadPointer((*unsafe.Pointer)(unsafe.Pointer(&d.dll))) != nil {
return nil
}
d.mu.Lock()
defer d.mu.Unlock()
if d.dll != nil {
return nil
}
// kernel32.dll is special, since it's where LoadLibraryEx comes from.
// The kernel already special-cases its name, so it's always
// loaded from system32.
var dll *DLL
var err error
if d.Name == "kernel32.dll" {
dll, err = LoadDLL(d.Name)
} else {
dll, err = loadLibraryEx(d.Name, d.System)
}
if err != nil {
return err
}
// Non-racy version of:
// d.dll = dll
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&d.dll)), unsafe.Pointer(dll))
return nil
}
func (v *VBucket) setVBMeta(newMeta *VBMeta) (err error) {
// This should only be called when holding the bucketstore
// service/apply "lock", to ensure a Flush between changes stream
// update and COLL_VBMETA update is atomic.
var j []byte
j, err = json.Marshal(newMeta)
if err != nil {
return err
}
k := []byte(fmt.Sprintf("%d", v.vbid))
i := &item{
key: nil, // A nil key means it's a VBMeta change.
cas: newMeta.MetaCas,
data: j,
}
deltaItemBytes, err := v.ps.set(i, nil)
if err != nil {
return err
}
if err = v.bs.collMeta(COLL_VBMETA).Set(k, j); err != nil {
return err
}
atomic.StorePointer(&v.meta, unsafe.Pointer(newMeta))
atomic.AddInt64(&v.stats.ItemBytes, deltaItemBytes)
atomic.AddInt64(v.bucketItemBytes, deltaItemBytes)
return nil
}
// updateTicket 从微信服务器获取新的 jsapi_ticket 并存入缓存, 同时返回该 jsapi_ticket.
func (srv *DefaultTicketServer) updateTicket(currentTicket string) (ticket *jsapiTicket, cached bool, err error) {
if currentTicket != "" {
if p := (*jsapiTicket)(atomic.LoadPointer(&srv.ticketCache)); p != nil && currentTicket != p.Ticket {
return p, true, nil // 无需更改 p.ExpiresIn 参数值, cached == true 时用不到
}
}
var incompleteURL = "https://api.weixin.qq.com/cgi-bin/ticket/getticket?type=jsapi&access_token="
var result struct {
core.Error
jsapiTicket
}
if err = srv.coreClient.GetJSON(incompleteURL, &result); err != nil {
atomic.StorePointer(&srv.ticketCache, nil)
return
}
if result.ErrCode != core.ErrCodeOK {
atomic.StorePointer(&srv.ticketCache, nil)
err = &result.Error
return
}
// 由于网络的延时, jsapi_ticket 过期时间留有一个缓冲区
switch {
case result.ExpiresIn > 31556952: // 60*60*24*365.2425
atomic.StorePointer(&srv.ticketCache, nil)
err = errors.New("expires_in too large: " + strconv.FormatInt(result.ExpiresIn, 10))
return
case result.ExpiresIn > 60*60:
result.ExpiresIn -= 60 * 10
case result.ExpiresIn > 60*30:
result.ExpiresIn -= 60 * 5
case result.ExpiresIn > 60*5:
result.ExpiresIn -= 60
case result.ExpiresIn > 60:
result.ExpiresIn -= 10
default:
atomic.StorePointer(&srv.ticketCache, nil)
err = errors.New("expires_in too small: " + strconv.FormatInt(result.ExpiresIn, 10))
return
}
ticketCopy := result.jsapiTicket
atomic.StorePointer(&srv.ticketCache, unsafe.Pointer(&ticketCopy))
ticket = &ticketCopy
return
}
func (s *Server) updateNow() {
tc := calculateTimeCounter(true)
// write atomically
atomic.StorePointer(&s.tcPool, unsafe.Pointer(&tc))
if log.V(4) {
log.Infoln("updateTimeCounterThread", len(tc))
}
}
// Unmarshals JSON representation of root node file location.
func (t *Collection) UnmarshalJSON(d []byte) error {
p := ploc{}
if err := json.Unmarshal(d, &p); err != nil {
return err
}
atomic.StorePointer(&t.root, unsafe.Pointer(&nodeLoc{loc: unsafe.Pointer(&p)}))
return nil
}
// NewDistSender returns a batch.Sender instance which connects to the
// Cockroach cluster via the supplied gossip instance. Supplying a
// DistSenderContext or the fields within is optional. For omitted values, sane
// defaults will be used.
func NewDistSender(ctx *DistSenderContext, gossip *gossip.Gossip) *DistSender {
if ctx == nil {
ctx = &DistSenderContext{}
}
clock := ctx.Clock
if clock == nil {
clock = hlc.NewClock(hlc.UnixNano)
}
ds := &DistSender{
clock: clock,
gossip: gossip,
}
if ctx.nodeDescriptor != nil {
atomic.StorePointer(&ds.nodeDescriptor, unsafe.Pointer(ctx.nodeDescriptor))
}
rcSize := ctx.RangeDescriptorCacheSize
if rcSize <= 0 {
rcSize = defaultRangeDescriptorCacheSize
}
rdb := ctx.RangeDescriptorDB
if rdb == nil {
rdb = ds
}
ds.rangeCache = newRangeDescriptorCache(rdb, int(rcSize))
lcSize := ctx.LeaderCacheSize
if lcSize <= 0 {
lcSize = defaultLeaderCacheSize
}
ds.leaderCache = newLeaderCache(int(lcSize))
if ctx.RangeLookupMaxRanges <= 0 {
ds.rangeLookupMaxRanges = defaultRangeLookupMaxRanges
}
if ctx.TransportFactory != nil {
ds.transportFactory = ctx.TransportFactory
}
ds.rpcRetryOptions = base.DefaultRetryOptions()
if ctx.RPCRetryOptions != nil {
ds.rpcRetryOptions = *ctx.RPCRetryOptions
}
if ctx.RPCContext != nil {
ds.rpcContext = ctx.RPCContext
if ds.rpcRetryOptions.Closer == nil {
ds.rpcRetryOptions.Closer = ds.rpcContext.Stopper.ShouldDrain()
}
}
if ctx.Tracer != nil {
ds.Tracer = ctx.Tracer
} else {
ds.Tracer = tracing.NewTracer()
}
if ctx.SendNextTimeout != 0 {
ds.sendNextTimeout = ctx.SendNextTimeout
} else {
ds.sendNextTimeout = defaultSendNextTimeout
}
return ds
}
func (s *Server) reloadConf() error {
if cfg, err := readConfig(s.conffile); err != nil {
return err
} else {
atomic.StorePointer(&s.conf, unsafe.Pointer(cfg))
log.Printf("reload config file ok")
return nil
}
}
// Atomically update the service_roots field. Enables you to update
// service_roots without disrupting any GET or PUT operations that might
// already be in progress.
func (this *KeepClient) SetServiceRoots(svc []string) {
// Must be sorted for ShuffledServiceRoots() to produce consistent
// results.
roots := make([]string, len(svc))
copy(roots, svc)
sort.Strings(roots)
atomic.StorePointer((*unsafe.Pointer)(unsafe.Pointer(&this.service_roots)),
unsafe.Pointer(&roots))
}
func (s *Stack) tryPushExchanger(v interface{}) bool {
// TODO time out
slotptr := &s.exchangers[rand.Intn(nExchangers)]
for i := 0; i < 100; i++ {
oldSlot := atomic.LoadPointer(slotptr)
switch (*exchanger)(oldSlot).state {
case stateFree:
newSlot := unsafe.Pointer(&exchanger{
value: v,
state: statePushing,
})
if !atomic.CompareAndSwapPointer(slotptr, oldSlot, newSlot) {
break
}
for j := 0; j < 100; j++ {
currentSlot := atomic.LoadPointer(slotptr)
if (*exchanger)(currentSlot).state != stateExchanging {
continue
}
atomic.StorePointer(slotptr, unsafe.Pointer(newExchanger()))
return true
}
if !atomic.CompareAndSwapPointer(slotptr, newSlot, oldSlot) {
atomic.StorePointer(slotptr, unsafe.Pointer(newExchanger()))
return true
}
return false
case statePushing:
return false
case statePoping:
newSlot := unsafe.Pointer(&exchanger{
value: v,
state: stateExchanging,
})
if !atomic.CompareAndSwapPointer(slotptr, oldSlot, newSlot) {
break
}
return true
case stateExchanging:
return false
}
}
return false
}
