src/ipc/Kid.cc

   1 /*
   2  * Copyright (C) 1996-2023 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 #include "squid.h"
  12 #include "globals.h"
  13 #include "ipc/Kid.h"
  14 #include "SquidConfig.h"
  15
  16 #include <ctime>
  17 #if HAVE_SYS_WAIT_H
  18 #include <sys/wait.h>
  19 #endif
  20
  21 int TheProcessKind = pkOther;
  22
  23 Kid::Kid()
  24 {
  25 }
  26
  27 Kid::Kid(const char *aRole, const int anId):
  28     processRole(aRole),
  29     processId(anId)
  30 {
  31 }
  32
  33 /// called when this kid got started, records PID
  34 void Kid::start(pid_t cpid)
  35 {
  36     assert(!running());
  37     assert(cpid > 0);
  38
  39     isRunning = true;
  40     stopTime = 0;
  41     pid = cpid;
  42     startTime = squid_curtime;
  43 }
  44
  45 /// called when kid terminates, sets exiting status
  46 void
  47 Kid::stop(PidStatus const theExitStatus)
  48 {
  49     assert(running());
  50     assert(startTime != 0);
  51
  52     isRunning = false;
  53     stopTime = squid_curtime;
  54     status = theExitStatus;
  55
  56     if ((stopTime - startTime) < fastFailureTimeLimit)
  57         ++badFailures;
  58     else
  59         badFailures = 0; // the failures are not "frequent" [any more]
  60
  61     reportStopped(); // after all state changes
  62 }
  63
  64 /// describes a recently stopped kid
  65 void
  66 Kid::reportStopped() const
  67 {
  68     if (calledExit()) {
  69         syslog(LOG_NOTICE,
  70                "Squid Parent: %s process %d exited with status %d",
  71                gist().c_str(), pid, exitStatus());
  72     } else if (signaled()) {
  73         syslog(LOG_NOTICE,
  74                "Squid Parent: %s process %d exited due to signal %d with status %d",
  75                gist().c_str(), pid, termSignal(), exitStatus());
  76     } else {
  77         syslog(LOG_NOTICE, "Squid Parent: %s process %d exited",
  78                gist().c_str(), pid);
  79     }
  80
  81     if (hopeless() && Config.hopelessKidRevivalDelay) {
  82         syslog(LOG_NOTICE, "Squid Parent: %s process %d will not be restarted for %ld "
  83                "seconds due to repeated, frequent failures",
  84                gist().c_str(),
  85                pid,
  86                static_cast<long int>(Config.hopelessKidRevivalDelay));
  87     }
  88 }
  89
  90 /// returns true if tracking of kid is stopped
  91 bool Kid::running() const
  92 {
  93     return isRunning;
  94 }
  95
  96 /// returns true if master process should restart this kid
  97 bool Kid::shouldRestart() const
  98 {
  99     return !(running() ||
 100              exitedHappy() ||
 101              hopeless() ||
 102              shutting_down ||
 103              signaled(SIGINT) || // unexpected forced shutdown
 104              signaled(SIGTERM)); // unexpected forced shutdown
 105 }
 106
 107 /// returns current pid for a running kid and last pid for a stopped kid
 108 pid_t Kid::getPid() const
 109 {
 110     assert(pid > 0);
 111     return pid;
 112 }
 113
 114 /// whether the failures are "repeated and frequent"
 115 bool Kid::hopeless() const
 116 {
 117     return badFailures > badFailureLimit;
 118 }
 119
 120 /// returns true if the process terminated normally
 121 bool Kid::calledExit() const
 122 {
 123     return (pid > 0) && !running() && WIFEXITED(status);
 124 }
 125
 126 /// returns the exit status of the process
 127 int Kid::exitStatus() const
 128 {
 129     return WEXITSTATUS(status);
 130 }
 131
 132 /// whether the process exited with a given exit status code
 133 bool Kid::calledExit(int code) const
 134 {
 135     return calledExit() && (exitStatus() == code);
 136 }
 137
 138 /// whether the process exited with code 0
 139 bool Kid::exitedHappy() const
 140 {
 141     return calledExit(0);
 142 }
 143
 144 /// returns true if the kid was terminated by a signal
 145 bool Kid::signaled() const
 146 {
 147     return (pid > 0) && !running() && WIFSIGNALED(status);
 148 }
 149
 150 /// returns the number of the signal that caused the kid to terminate
 151 int Kid::termSignal() const
 152 {
 153     return WTERMSIG(status);
 154 }
 155
 156 /// whether the process was terminated by a given signal
 157 bool Kid::signaled(int sgnl) const
 158 {
 159     return signaled() && (termSignal() == sgnl);
 160 }
 161
 162 /// returns kid name
 163 SBuf Kid::processName() const
 164 {
 165     SBuf name("(");
 166     name.append(gist());
 167     name.append(")");
 168     return name;
 169 }
 170
 171 SBuf Kid::gist() const
 172 {
 173     SBuf name(processRole);
 174     name.appendf("-%d", processId);
 175     return name;
 176 }
 177
 178 time_t
 179 Kid::deathDuration() const
 180 {
 181     return squid_curtime > stopTime ? squid_curtime - stopTime : 0;
 182 }
 183