src/ipc/UdsOp.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 /* DEBUG: section 54    Interprocess Communication */
  10
  11 #ifndef SQUID_IPC_ASYNCUDSOP_H
  12 #define SQUID_IPC_ASYNCUDSOP_H
  13
  14 #include "base/AsyncJob.h"
  15 #include "cbdata.h"
  16 #include "comm/forward.h"
  17 #include "ipc/FdNotes.h"
  18 #include "ipc/TypedMsgHdr.h"
  19 #include "SquidString.h"
  20
  21 class CommTimeoutCbParams;
  22 class CommIoCbParams;
  23
  24 namespace Ipc
  25 {
  26
  27 /// code shared by unix-domain socket senders (e.g., UdsSender or Coordinator)
  28 /// and receivers (e.g. Port or Coordinator)
  29 class UdsOp: public AsyncJob
  30 {
  31 public:
  32     UdsOp(const String &pathAddr);
  33     virtual ~UdsOp();
  34
  35 public:
  36     struct sockaddr_un address; ///< UDS address from path; treat as read-only
  37
  38 protected:
  39     virtual void timedout() {} ///< called after setTimeout() if timed out
  40
  41     Comm::ConnectionPointer &conn(); ///< creates if needed and returns raw UDS socket descriptor
  42
  43     /// call timedout() if no UDS messages in a given number of seconds
  44     void setTimeout(int seconds, const char *handlerName);
  45     void clearTimeout(); ///< remove previously set timeout, if any
  46
  47     void setOptions(int newOptions); ///< changes socket options
  48
  49 private:
  50     /// Comm timeout callback; calls timedout()
  51     void noteTimeout(const CommTimeoutCbParams &p);
  52
  53 private:
  54     int options; ///< UDS options
  55     Comm::ConnectionPointer conn_; ///< UDS descriptor
  56
  57 private:
  58     UdsOp(const UdsOp &); // not implemented
  59     UdsOp &operator= (const UdsOp &); // not implemented
  60 };
  61
  62 /// converts human-readable filename path into UDS address
  63 struct sockaddr_un PathToAddress(const String &pathAddr);
  64
  65 // XXX: move UdsSender code to UdsSender.{cc,h}
  66 /// attempts to send an IPC message a few times, with a timeout
  67 class UdsSender: public UdsOp
  68 {
  69     CBDATA_CLASS(UdsSender);
  70
  71 public:
  72     UdsSender(const String& pathAddr, const TypedMsgHdr& aMessage);
  73
  74 protected:
  75     virtual void swanSong(); // UdsOp (AsyncJob) API
  76     virtual void start(); // UdsOp (AsyncJob) API
  77     virtual bool doneAll() const; // UdsOp (AsyncJob) API
  78     virtual void timedout(); // UdsOp API
  79
  80 private:
  81     void startSleep();
  82     void cancelSleep();
  83     static void DelayedRetry(void *data);
  84     void delayedRetry();
  85
  86     void write(); ///< schedule writing
  87     void wrote(const CommIoCbParams& params); ///< done writing or error
  88
  89 private:
  90     TypedMsgHdr message; ///< what to send
  91     int retries; ///< how many times to try after a write error
  92     int timeout; ///< total time to send the message
  93     bool sleeping; ///< whether we are waiting to retry a failed write
  94     bool writing; ///< whether Comm started and did not finish writing
  95
  96 private:
  97     UdsSender(const UdsSender&); // not implemented
  98     UdsSender& operator= (const UdsSender&); // not implemented
  99 };
 100
 101 void SendMessage(const String& toAddress, const TypedMsgHdr& message);
 102 /// import socket fd from another strand into our Comm state
 103 const Comm::ConnectionPointer & ImportFdIntoComm(const Comm::ConnectionPointer &conn, int socktype, int protocol, FdNoteId noteId);
 104
 105 }
 106
 107 #endif /* SQUID_IPC_ASYNCUDSOP_H */
 108