src/comm/ConnOpener.h

   1 /*
   2  * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef _SQUID_SRC_COMM_OPENERSTATEDATA_H
  10 #define _SQUID_SRC_COMM_OPENERSTATEDATA_H
  11
  12 #include "base/AsyncCall.h"
  13 #include "base/AsyncJob.h"
  14 #include "cbdata.h"
  15 #include "comm/Flag.h"
  16 #include "comm/forward.h"
  17 #include "CommCalls.h"
  18
  19 namespace Comm
  20 {
  21
  22 /**
  23  * Async-opener of a Comm connection.
  24  */
  25 class ConnOpener : public AsyncJob
  26 {
  27     CBDATA_CLASS(ConnOpener);
  28
  29 public:
  30     void noteAbort() { mustStop("externally aborted"); }
  31
  32     typedef CbcPointer<ConnOpener> Pointer;
  33
  34     virtual bool doneAll() const;
  35
  36     ConnOpener(Comm::ConnectionPointer &, AsyncCall::Pointer &handler, time_t connect_timeout);
  37     ~ConnOpener();
  38
  39     void setHost(const char *);    ///< set the hostname note for this connection
  40     const char * getHost() const;  ///< get the hostname noted for this connection
  41
  42 protected:
  43     virtual void start();
  44     virtual void swanSong();
  45
  46 private:
  47     // Undefined because two openers cannot share a connection
  48     ConnOpener(const ConnOpener &);
  49     ConnOpener & operator =(const ConnOpener &c);
  50
  51     void earlyAbort(const CommCloseCbParams &);
  52     void timeout(const CommTimeoutCbParams &);
  53     void sendAnswer(Comm::Flag errFlag, int xerrno, const char *why);
  54     static void InProgressConnectRetry(int fd, void *data);
  55     static void DelayedConnectRetry(void *data);
  56     void doConnect();
  57     void connected();
  58     void lookupLocalAddress();
  59
  60     void retrySleep();
  61     void restart();
  62
  63     bool createFd();
  64     void closeFd();
  65     void keepFd();
  66     void cleanFd();
  67
  68     void cancelSleep();
  69
  70 private:
  71     char *host_;                         ///< domain name we are trying to connect to.
  72     int temporaryFd_;                    ///< the FD being opened. Do NOT set conn_->fd until it is fully open.
  73     Comm::ConnectionPointer conn_;       ///< single connection currently to be opened.
  74     AsyncCall::Pointer callback_;        ///< handler to be called on connection completion.
  75
  76     int totalTries_;   ///< total number of connection attempts over all destinations so far.
  77     int failRetries_;  ///< number of retries current destination has been tried.
  78
  79     /// if we are not done by then, we will call back with Comm::TIMEOUT
  80     time_t deadline_;
  81
  82     /// handles to calls which we may need to cancel.
  83     struct Calls {
  84         AsyncCall::Pointer earlyAbort_;
  85         AsyncCall::Pointer timeout_;
  86         /// Whether we are idling before retrying to connect; not yet a call
  87         /// [that we can cancel], but it will probably become one eventually.
  88         bool sleep_;
  89     } calls_;
  90 };
  91
  92 }; // namespace Comm
  93
  94 #endif /* _SQUID_SRC_COMM_CONNOPENER_H */
  95