src/base/AsyncCall.cc

   1 /*
   2  * Copyright (C) 1996-2018 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 #include "squid.h"
  10 #include "AsyncCall.h"
  11 #include "base/AsyncCall.h"
  12 #include "base/AsyncCallQueue.h"
  13 #include "cbdata.h"
  14 #include "Debug.h"
  15 #include <ostream>
  16
  17 InstanceIdDefinitions(AsyncCall, "call");
  18
  19 /* AsyncCall */
  20
  21 AsyncCall::AsyncCall(int aDebugSection, int aDebugLevel,
  22                      const char *aName): name(aName), debugSection(aDebugSection),
  23     debugLevel(aDebugLevel), theNext(0), isCanceled(NULL)
  24 {
  25     debugs(debugSection, debugLevel, "The AsyncCall " << name << " constructed, this=" << this <<
  26            " [" << id << ']');
  27 }
  28
  29 AsyncCall::~AsyncCall()
  30 {
  31     assert(!theNext); // AsyncCallQueue must clean
  32 }
  33
  34 void
  35 AsyncCall::make()
  36 {
  37     debugs(debugSection, debugLevel, HERE << "make call " << name <<
  38            " [" << id << ']');
  39     if (canFire()) {
  40         fire();
  41         return;
  42     }
  43
  44     if (!isCanceled) // we did not cancel() when returning false from canFire()
  45         isCanceled = "unknown reason";
  46
  47     debugs(debugSection, debugLevel, HERE << "will not call " << name <<
  48            " [" << id << ']' << " because of " << isCanceled);
  49 }
  50
  51 bool
  52 AsyncCall::cancel(const char *reason)
  53 {
  54     debugs(debugSection, debugLevel, HERE << "will not call " << name <<
  55            " [" << id << "] " << (isCanceled ? "also " : "") <<
  56            "because " << reason);
  57
  58     isCanceled = reason;
  59     return false;
  60 }
  61
  62 bool
  63 AsyncCall::canFire()
  64 {
  65     return !isCanceled;
  66 }
  67
  68 /// \todo make this method const by providing a const getDialer()
  69 void
  70 AsyncCall::print(std::ostream &os)
  71 {
  72     os << name;
  73     if (const CallDialer *dialer = getDialer())
  74         dialer->print(os);
  75     else
  76         os << "(?" << this << "?)";
  77 }
  78
  79 void
  80 AsyncCall::dequeue(AsyncCall::Pointer &head, AsyncCall::Pointer &prev)
  81 {
  82     if (prev != NULL)
  83         prev->setNext(Next());
  84     else
  85         head = Next();
  86     setNext(NULL);
  87 }
  88
  89 bool
  90 ScheduleCall(const char *fileName, int fileLine, AsyncCall::Pointer &call)
  91 {
  92     debugs(call->debugSection, call->debugLevel, fileName << "(" << fileLine <<
  93            ") will call " << *call << " [" << call->id << ']' );
  94     AsyncCallQueue::Instance().schedule(call);
  95     return true;
  96 }
  97