gecko/netwerk/protocol/http/nsHttpConnectionMgr.h
2012-07-30 17:20:58 +03:00

623 lines
26 KiB
C++

/* vim:set ts=4 sw=4 sts=4 et cin: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsHttpConnectionMgr_h__
#define nsHttpConnectionMgr_h__
#include "nsHttpConnectionInfo.h"
#include "nsHttpConnection.h"
#include "nsHttpTransaction.h"
#include "NullHttpTransaction.h"
#include "nsTArray.h"
#include "nsThreadUtils.h"
#include "nsClassHashtable.h"
#include "nsDataHashtable.h"
#include "nsAutoPtr.h"
#include "mozilla/ReentrantMonitor.h"
#include "nsISocketTransportService.h"
#include "mozilla/TimeStamp.h"
#include "mozilla/Attributes.h"
#include "nsIObserver.h"
#include "nsITimer.h"
#include "nsIX509Cert3.h"
class nsHttpPipeline;
class nsIHttpUpgradeListener;
//-----------------------------------------------------------------------------
class nsHttpConnectionMgr : public nsIObserver
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIOBSERVER
// parameter names
enum nsParamName {
MAX_CONNECTIONS,
MAX_PERSISTENT_CONNECTIONS_PER_HOST,
MAX_PERSISTENT_CONNECTIONS_PER_PROXY,
MAX_REQUEST_DELAY,
MAX_PIPELINED_REQUESTS,
MAX_OPTIMISTIC_PIPELINED_REQUESTS
};
//-------------------------------------------------------------------------
// NOTE: functions below may only be called on the main thread.
//-------------------------------------------------------------------------
nsHttpConnectionMgr();
nsresult Init(PRUint16 maxConnections,
PRUint16 maxPersistentConnectionsPerHost,
PRUint16 maxPersistentConnectionsPerProxy,
PRUint16 maxRequestDelay,
PRUint16 maxPipelinedRequests,
PRUint16 maxOptimisticPipelinedRequests);
nsresult Shutdown();
//-------------------------------------------------------------------------
// NOTE: functions below may be called on any thread.
//-------------------------------------------------------------------------
// Schedules next pruning of dead connection to happen after
// given time.
void PruneDeadConnectionsAfter(PRUint32 time);
// Stops timer scheduled for next pruning of dead connections if
// there are no more idle connections or active spdy ones
void ConditionallyStopPruneDeadConnectionsTimer();
// Stops timer used for the read timeout tick if there are no currently
// active connections.
void ConditionallyStopTimeoutTick();
// adds a transaction to the list of managed transactions.
nsresult AddTransaction(nsHttpTransaction *, PRInt32 priority);
// called to reschedule the given transaction. it must already have been
// added to the connection manager via AddTransaction.
nsresult RescheduleTransaction(nsHttpTransaction *, PRInt32 priority);
// cancels a transaction w/ the given reason.
nsresult CancelTransaction(nsHttpTransaction *, nsresult reason);
// called to force the connection manager to prune its list of idle
// connections.
nsresult PruneDeadConnections();
// Close all idle persistent connections and prevent any active connections
// from being reused.
nsresult ClosePersistentConnections();
// called to get a reference to the socket transport service. the socket
// transport service is not available when the connection manager is down.
nsresult GetSocketThreadTarget(nsIEventTarget **);
// called to indicate a transaction for the connectionInfo is likely coming
// soon. The connection manager may use this information to start a TCP
// and/or SSL level handshake for that resource immediately so that it is
// ready when the transaction is submitted. No obligation is taken on by the
// connection manager, nor is the submitter obligated to actually submit a
// real transaction for this connectionInfo.
nsresult SpeculativeConnect(nsHttpConnectionInfo *,
nsIInterfaceRequestor *,
nsIEventTarget *);
// called when a connection is done processing a transaction. if the
// connection can be reused then it will be added to the idle list, else
// it will be closed.
nsresult ReclaimConnection(nsHttpConnection *conn);
// called by the main thread to execute the taketransport() logic on the
// socket thread after a 101 response has been received and the socket
// needs to be transferred to an expectant upgrade listener such as
// websockets.
nsresult CompleteUpgrade(nsAHttpConnection *aConn,
nsIHttpUpgradeListener *aUpgradeListener);
// called to update a parameter after the connection manager has already
// been initialized.
nsresult UpdateParam(nsParamName name, PRUint16 value);
// Lookup/Cancel HTTP->SPDY redirections
bool GetSpdyAlternateProtocol(nsACString &key);
void ReportSpdyAlternateProtocol(nsHttpConnection *);
void RemoveSpdyAlternateProtocol(nsACString &key);
// Pipielining Interfaces and Datatypes
const static PRUint32 kPipelineInfoTypeMask = 0xffff0000;
const static PRUint32 kPipelineInfoIDMask = ~kPipelineInfoTypeMask;
const static PRUint32 kPipelineInfoTypeRed = 0x00010000;
const static PRUint32 kPipelineInfoTypeBad = 0x00020000;
const static PRUint32 kPipelineInfoTypeNeutral = 0x00040000;
const static PRUint32 kPipelineInfoTypeGood = 0x00080000;
enum PipelineFeedbackInfoType
{
// Used when an HTTP response less than 1.1 is received
RedVersionTooLow = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0001,
// Used when a HTTP Server response header that is on the banned from
// pipelining list is received
RedBannedServer = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0002,
// Used when a response is terminated early, when it fails an
// integrity check such as assoc-req or when a 304 contained a Last-Modified
// differnet than the entry being validated.
RedCorruptedContent = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0004,
// Used when a pipeline is only partly satisfied - for instance if the
// server closed the connection after responding to the first
// request but left some requests unprocessed.
RedCanceledPipeline = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0005,
// Used when a connection that we expected to stay persistently open
// was closed by the server. Not used when simply timed out.
BadExplicitClose = kPipelineInfoTypeBad | 0x0003,
// Used when there is a gap of around 400 - 1200ms in between data being
// read from the server
BadSlowReadMinor = kPipelineInfoTypeBad | 0x0006,
// Used when there is a gap of > 1200ms in between data being
// read from the server
BadSlowReadMajor = kPipelineInfoTypeBad | 0x0007,
// Used when a response is received that is not framed with either chunked
// encoding or a complete content length.
BadInsufficientFraming = kPipelineInfoTypeBad | 0x0008,
// Used when a very large response is recevied in a potential pipelining
// context. Large responses cause head of line blocking.
BadUnexpectedLarge = kPipelineInfoTypeBad | 0x000B,
// Used when a response is received that has headers that appear to support
// pipelining.
NeutralExpectedOK = kPipelineInfoTypeNeutral | 0x0009,
// Used when a response is received successfully to a pipelined request.
GoodCompletedOK = kPipelineInfoTypeGood | 0x000A
};
// called to provide information relevant to the pipelining manager
// may be called from any thread
void PipelineFeedbackInfo(nsHttpConnectionInfo *,
PipelineFeedbackInfoType info,
nsHttpConnection *,
PRUint32);
void ReportFailedToProcess(nsIURI *uri);
// Causes a large amount of connection diagnostic information to be
// printed to the javascript console
void PrintDiagnostics();
//-------------------------------------------------------------------------
// NOTE: functions below may be called only on the socket thread.
//-------------------------------------------------------------------------
// called to force the transaction queue to be processed once more, giving
// preference to the specified connection.
nsresult ProcessPendingQ(nsHttpConnectionInfo *);
bool ProcessPendingQForEntry(nsHttpConnectionInfo *);
// This is used to force an idle connection to be closed and removed from
// the idle connection list. It is called when the idle connection detects
// that the network peer has closed the transport.
nsresult CloseIdleConnection(nsHttpConnection *);
// The connection manager needs to know when a normal HTTP connection has been
// upgraded to SPDY because the dispatch and idle semantics are a little
// bit different.
void ReportSpdyConnection(nsHttpConnection *, bool usingSpdy);
bool SupportsPipelining(nsHttpConnectionInfo *);
private:
virtual ~nsHttpConnectionMgr();
enum PipeliningState {
// Host has proven itself pipeline capable through past experience and
// large pipeline depths are allowed on multiple connections.
PS_GREEN,
// Not enough information is available yet with this host to be certain
// of pipeline capability. Small pipelines on a single connection are
// allowed in order to decide whether or not to proceed to green.
PS_YELLOW,
// One or more bad events has happened that indicate that pipelining
// to this host (or a particular type of transaction with this host)
// is a bad idea. Pipelining is not currently allowed, but time and
// other positive experiences will eventually allow it to try again.
PS_RED
};
class nsHalfOpenSocket;
// nsConnectionEntry
//
// mCT maps connection info hash key to nsConnectionEntry object, which
// contains list of active and idle connections as well as the list of
// pending transactions.
//
class nsConnectionEntry
{
public:
nsConnectionEntry(nsHttpConnectionInfo *ci);
~nsConnectionEntry();
nsHttpConnectionInfo *mConnInfo;
nsTArray<nsHttpTransaction*> mPendingQ; // pending transaction queue
nsTArray<nsHttpConnection*> mActiveConns; // active connections
nsTArray<nsHttpConnection*> mIdleConns; // idle persistent connections
nsTArray<nsHalfOpenSocket*> mHalfOpens;
// calculate the number of half open sockets that have not had at least 1
// connection complete
PRUint32 UnconnectedHalfOpens();
// Remove a particular half open socket from the mHalfOpens array
void RemoveHalfOpen(nsHalfOpenSocket *);
// Pipeline depths for various states
const static PRUint32 kPipelineUnlimited = 1024; // fully open - extended green
const static PRUint32 kPipelineOpen = 6; // 6 on each conn - normal green
const static PRUint32 kPipelineRestricted = 2; // 2 on just 1 conn in yellow
nsHttpConnectionMgr::PipeliningState PipelineState();
void OnPipelineFeedbackInfo(
nsHttpConnectionMgr::PipelineFeedbackInfoType info,
nsHttpConnection *, PRUint32);
bool SupportsPipelining();
PRUint32 MaxPipelineDepth(nsAHttpTransaction::Classifier classification);
void CreditPenalty();
nsHttpConnectionMgr::PipeliningState mPipelineState;
void SetYellowConnection(nsHttpConnection *);
void OnYellowComplete();
PRUint32 mYellowGoodEvents;
PRUint32 mYellowBadEvents;
nsHttpConnection *mYellowConnection;
// initialGreenDepth is the max depth of a pipeline when you first
// transition to green. Normally this is kPipelineOpen, but it can
// be kPipelineUnlimited in aggressive mode.
PRUint32 mInitialGreenDepth;
// greenDepth is the current max allowed depth of a pipeline when
// in the green state. Normally this starts as kPipelineOpen and
// grows to kPipelineUnlimited after a pipeline of depth 3 has been
// successfully transacted.
PRUint32 mGreenDepth;
// pipeliningPenalty is the current amount of penalty points this host
// entry has earned for participating in events that are not conducive
// to good pipelines - such as head of line blocking, canceled pipelines,
// etc.. penalties are paid back either through elapsed time or simply
// healthy transactions. Having penalty points means that this host is
// not currently eligible for pipelines.
PRInt16 mPipeliningPenalty;
// some penalty points only apply to particular classifications of
// transactions - this allows a server that perhaps has head of line
// blocking problems on CGI queries to still serve JS pipelined.
PRInt16 mPipeliningClassPenalty[nsAHttpTransaction::CLASS_MAX];
// for calculating penalty repair credits
mozilla::TimeStamp mLastCreditTime;
// Spdy sometimes resolves the address in the socket manager in order
// to re-coalesce sharded HTTP hosts. The dotted decimal address is
// combined with the Anonymous flag from the connection information
// to build the hash key for hosts in the same ip pool.
//
// When a set of hosts are coalesced together one of them is marked
// mSpdyPreferred. The mapping is maintained in the connection mananger
// mSpdyPreferred hash.
//
nsCString mCoalescingKey;
// To have the UsingSpdy flag means some host with the same connection
// entry has done NPN=spdy/* at some point. It does not mean every
// connection is currently using spdy.
bool mUsingSpdy;
// mTestedSpdy is set after NPN negotiation has occurred and we know
// with confidence whether a host speaks spdy or not (which is reflected
// in mUsingSpdy). Before mTestedSpdy is set, handshake parallelism is
// minimized so that we can multiplex on a single spdy connection.
bool mTestedSpdy;
bool mSpdyPreferred;
};
// nsConnectionHandle
//
// thin wrapper around a real connection, used to keep track of references
// to the connection to determine when the connection may be reused. the
// transaction (or pipeline) owns a reference to this handle. this extra
// layer of indirection greatly simplifies consumer code, avoiding the
// need for consumer code to know when to give the connection back to the
// connection manager.
//
class nsConnectionHandle : public nsAHttpConnection
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSAHTTPCONNECTION(mConn)
nsConnectionHandle(nsHttpConnection *conn) { NS_ADDREF(mConn = conn); }
virtual ~nsConnectionHandle();
nsHttpConnection *mConn;
};
// nsHalfOpenSocket is used to hold the state of an opening TCP socket
// while we wait for it to establish and bind it to a connection
class nsHalfOpenSocket MOZ_FINAL : public nsIOutputStreamCallback,
public nsITransportEventSink,
public nsIInterfaceRequestor,
public nsITimerCallback
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSIOUTPUTSTREAMCALLBACK
NS_DECL_NSITRANSPORTEVENTSINK
NS_DECL_NSIINTERFACEREQUESTOR
NS_DECL_NSITIMERCALLBACK
nsHalfOpenSocket(nsConnectionEntry *ent,
nsAHttpTransaction *trans,
PRUint8 caps);
~nsHalfOpenSocket();
nsresult SetupStreams(nsISocketTransport **,
nsIAsyncInputStream **,
nsIAsyncOutputStream **,
bool isBackup);
nsresult SetupPrimaryStreams();
nsresult SetupBackupStreams();
void SetupBackupTimer();
void CancelBackupTimer();
void Abandon();
double Duration(mozilla::TimeStamp epoch);
nsISocketTransport *SocketTransport() { return mSocketTransport; }
nsISocketTransport *BackupTransport() { return mBackupTransport; }
nsAHttpTransaction *Transaction() { return mTransaction; }
bool IsSpeculative() { return mSpeculative; }
void SetSpeculative(bool val) { mSpeculative = val; }
bool HasConnected() { return mHasConnected; }
void PrintDiagnostics(nsCString &log);
private:
nsConnectionEntry *mEnt;
nsRefPtr<nsAHttpTransaction> mTransaction;
nsCOMPtr<nsISocketTransport> mSocketTransport;
nsCOMPtr<nsIAsyncOutputStream> mStreamOut;
nsCOMPtr<nsIAsyncInputStream> mStreamIn;
PRUint8 mCaps;
// mSpeculative is set if the socket was created from
// SpeculativeConnect(). It is cleared when a transaction would normally
// start a new connection from scratch but instead finds this one in
// the half open list and claims it for its own use. (which due to
// the vagaries of scheduling from the pending queue might not actually
// match up - but it prevents a speculative connection from opening
// more connections that are needed.)
bool mSpeculative;
mozilla::TimeStamp mPrimarySynStarted;
mozilla::TimeStamp mBackupSynStarted;
// for syn retry
nsCOMPtr<nsITimer> mSynTimer;
nsCOMPtr<nsISocketTransport> mBackupTransport;
nsCOMPtr<nsIAsyncOutputStream> mBackupStreamOut;
nsCOMPtr<nsIAsyncInputStream> mBackupStreamIn;
bool mHasConnected;
};
friend class nsHalfOpenSocket;
//-------------------------------------------------------------------------
// NOTE: these members may be accessed from any thread (use mReentrantMonitor)
//-------------------------------------------------------------------------
PRInt32 mRef;
mozilla::ReentrantMonitor mReentrantMonitor;
nsCOMPtr<nsIEventTarget> mSocketThreadTarget;
// connection limits
PRUint16 mMaxConns;
PRUint16 mMaxPersistConnsPerHost;
PRUint16 mMaxPersistConnsPerProxy;
PRUint16 mMaxRequestDelay; // in seconds
PRUint16 mMaxPipelinedRequests;
PRUint16 mMaxOptimisticPipelinedRequests;
bool mIsShuttingDown;
//-------------------------------------------------------------------------
// NOTE: these members are only accessed on the socket transport thread
//-------------------------------------------------------------------------
static PLDHashOperator ProcessOneTransactionCB(const nsACString &, nsAutoPtr<nsConnectionEntry> &, void *);
static PLDHashOperator PruneDeadConnectionsCB(const nsACString &, nsAutoPtr<nsConnectionEntry> &, void *);
static PLDHashOperator ShutdownPassCB(const nsACString &, nsAutoPtr<nsConnectionEntry> &, void *);
static PLDHashOperator PurgeExcessIdleConnectionsCB(const nsACString &, nsAutoPtr<nsConnectionEntry> &, void *);
static PLDHashOperator ClosePersistentConnectionsCB(const nsACString &, nsAutoPtr<nsConnectionEntry> &, void *);
bool ProcessPendingQForEntry(nsConnectionEntry *);
bool IsUnderPressure(nsConnectionEntry *ent,
nsHttpTransaction::Classifier classification);
bool AtActiveConnectionLimit(nsConnectionEntry *, PRUint8 caps);
nsresult TryDispatchTransaction(nsConnectionEntry *ent,
bool onlyReusedConnection,
nsHttpTransaction *trans);
nsresult DispatchTransaction(nsConnectionEntry *,
nsHttpTransaction *,
nsHttpConnection *);
nsresult DispatchAbstractTransaction(nsConnectionEntry *,
nsAHttpTransaction *,
PRUint8,
nsHttpConnection *,
PRInt32);
nsresult BuildPipeline(nsConnectionEntry *,
nsAHttpTransaction *,
nsHttpPipeline **);
bool RestrictConnections(nsConnectionEntry *);
nsresult ProcessNewTransaction(nsHttpTransaction *);
nsresult EnsureSocketThreadTargetIfOnline();
void ClosePersistentConnections(nsConnectionEntry *ent);
nsresult CreateTransport(nsConnectionEntry *, nsAHttpTransaction *,
PRUint8, bool);
void AddActiveConn(nsHttpConnection *, nsConnectionEntry *);
void StartedConnect();
void RecvdConnect();
nsConnectionEntry *GetOrCreateConnectionEntry(nsHttpConnectionInfo *);
bool MakeNewConnection(nsConnectionEntry *ent,
nsHttpTransaction *trans);
bool AddToShortestPipeline(nsConnectionEntry *ent,
nsHttpTransaction *trans,
nsHttpTransaction::Classifier classification,
PRUint16 depthLimit);
// Manage the preferred spdy connection entry for this address
nsConnectionEntry *GetSpdyPreferredEnt(nsConnectionEntry *aOriginalEntry);
void RemoveSpdyPreferredEnt(nsACString &aDottedDecimal);
nsHttpConnection *GetSpdyPreferredConn(nsConnectionEntry *ent);
nsDataHashtable<nsCStringHashKey, nsConnectionEntry *> mSpdyPreferredHash;
nsConnectionEntry *LookupConnectionEntry(nsHttpConnectionInfo *ci,
nsHttpConnection *conn,
nsHttpTransaction *trans);
void ProcessSpdyPendingQ(nsConnectionEntry *ent);
void ProcessAllSpdyPendingQ();
static PLDHashOperator ProcessSpdyPendingQCB(
const nsACString &key, nsAutoPtr<nsConnectionEntry> &ent,
void *closure);
// message handlers have this signature
typedef void (nsHttpConnectionMgr:: *nsConnEventHandler)(PRInt32, void *);
// nsConnEvent
//
// subclass of nsRunnable used to marshall events to the socket transport
// thread. this class is used to implement PostEvent.
//
class nsConnEvent;
friend class nsConnEvent;
class nsConnEvent : public nsRunnable
{
public:
nsConnEvent(nsHttpConnectionMgr *mgr,
nsConnEventHandler handler,
PRInt32 iparam,
void *vparam)
: mMgr(mgr)
, mHandler(handler)
, mIParam(iparam)
, mVParam(vparam)
{
NS_ADDREF(mMgr);
}
NS_IMETHOD Run()
{
(mMgr->*mHandler)(mIParam, mVParam);
return NS_OK;
}
private:
virtual ~nsConnEvent()
{
NS_RELEASE(mMgr);
}
nsHttpConnectionMgr *mMgr;
nsConnEventHandler mHandler;
PRInt32 mIParam;
void *mVParam;
};
nsresult PostEvent(nsConnEventHandler handler,
PRInt32 iparam = 0,
void *vparam = nullptr);
// message handlers
void OnMsgShutdown (PRInt32, void *);
void OnMsgNewTransaction (PRInt32, void *);
void OnMsgReschedTransaction (PRInt32, void *);
void OnMsgCancelTransaction (PRInt32, void *);
void OnMsgProcessPendingQ (PRInt32, void *);
void OnMsgPruneDeadConnections (PRInt32, void *);
void OnMsgSpeculativeConnect (PRInt32, void *);
void OnMsgReclaimConnection (PRInt32, void *);
void OnMsgCompleteUpgrade (PRInt32, void *);
void OnMsgUpdateParam (PRInt32, void *);
void OnMsgClosePersistentConnections (PRInt32, void *);
void OnMsgProcessFeedback (PRInt32, void *);
// Total number of active connections in all of the ConnectionEntry objects
// that are accessed from mCT connection table.
PRUint16 mNumActiveConns;
// Total number of idle connections in all of the ConnectionEntry objects
// that are accessed from mCT connection table.
PRUint16 mNumIdleConns;
// Holds time in seconds for next wake-up to prune dead connections.
PRUint64 mTimeOfNextWakeUp;
// Timer for next pruning of dead connections.
nsCOMPtr<nsITimer> mTimer;
// A 1s tick to call nsHttpConnection::ReadTimeoutTick on
// active http/1 connections and check for orphaned half opens.
// Disabled when there are no active or half open connections.
nsCOMPtr<nsITimer> mTimeoutTick;
bool mTimeoutTickArmed;
//
// the connection table
//
// this table is indexed by connection key. each entry is a
// nsConnectionEntry object.
//
nsClassHashtable<nsCStringHashKey, nsConnectionEntry> mCT;
// mAlternateProtocolHash is used only for spdy/* upgrades for now
// protected by the monitor
nsTHashtable<nsCStringHashKey> mAlternateProtocolHash;
static PLDHashOperator TrimAlternateProtocolHash(nsCStringHashKey *entry,
void *closure);
// Read Timeout Tick handlers
void ActivateTimeoutTick();
void TimeoutTick();
static PLDHashOperator TimeoutTickCB(const nsACString &key,
nsAutoPtr<nsConnectionEntry> &ent,
void *closure);
// For diagnostics
void OnMsgPrintDiagnostics(PRInt32, void *);
static PLDHashOperator PrintDiagnosticsCB(const nsACString &key,
nsAutoPtr<nsConnectionEntry> &ent,
void *closure);
nsCString mLogData;
};
#endif // !nsHttpConnectionMgr_h__