src/ipc/Kid.cc

   1 /*
   2  * $Id$
   3  *
   4  * DEBUG: section 54    Interprocess Communication
   5  *
   6  */
   7
   8 #include "config.h"
   9 #include "globals.h"
  10 #include "ipc/Kid.h"
  11
  12 #if HAVE_SYS_WAIT_H
  13 #include <sys/wait.h>
  14 #endif
  15
  16 Kid::Kid():
  17         badFailures(0),
  18         pid(-1),
  19         startTime(0),
  20         isRunning(false)
  21 {
  22 }
  23
  24 Kid::Kid(const String& kid_name):
  25         theName(kid_name),
  26         badFailures(0),
  27         pid(-1),
  28         startTime(0),
  29         isRunning(false)
  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     pid = cpid;
  41     time(&startTime);
  42 }
  43
  44 /// called when kid terminates, sets exiting status
  45 void Kid::stop(status_type exitStatus)
  46 {
  47     assert(running());
  48     assert(startTime != 0);
  49
  50     isRunning = false;
  51
  52     time_t stop_time;
  53     time(&stop_time);
  54     if ((stop_time - startTime) < fastFailureTimeLimit)
  55         badFailures++;
  56     else
  57         badFailures = 0; // the failures are not "frequent" [any more]
  58
  59     status = exitStatus;
  60 }
  61
  62 /// returns true if tracking of kid is stopped
  63 bool Kid::running() const
  64 {
  65     return isRunning;
  66 }
  67
  68 /// returns true if master process should restart this kid
  69 bool Kid::shouldRestart() const
  70 {
  71     return !(running() ||
  72              exitedHappy() ||
  73              hopeless() ||
  74              shutting_down ||
  75              signaled(SIGKILL) || // squid -k kill
  76              signaled(SIGINT) || // unexpected forced shutdown
  77              signaled(SIGTERM)); // unexpected forced shutdown
  78 }
  79
  80 /// returns current pid for a running kid and last pid for a stopped kid
  81 pid_t Kid::getPid() const
  82 {
  83     assert(pid > 0);
  84     return pid;
  85 }
  86
  87 /// whether the failures are "repeated and frequent"
  88 bool Kid::hopeless() const
  89 {
  90     return badFailures > badFailureLimit;
  91 }
  92
  93 /// returns true if the process terminated normally
  94 bool Kid::calledExit() const
  95 {
  96     return (pid > 0) && !running() && WIFEXITED(status);
  97 }
  98
  99 /// returns the exit status of the process
 100 int Kid::exitStatus() const
 101 {
 102     return WEXITSTATUS(status);
 103 }
 104
 105 /// whether the process exited with a given exit status code
 106 bool Kid::calledExit(int code) const
 107 {
 108     return calledExit() && (exitStatus() == code);
 109 }
 110
 111 /// whether the process exited with code 0
 112 bool Kid::exitedHappy() const
 113 {
 114     return calledExit(0);
 115 }
 116
 117 /// returns true if the kid was terminated by a signal
 118 bool Kid::signaled() const
 119 {
 120     return (pid > 0) && !running() && WIFSIGNALED(status);
 121 }
 122
 123 /// returns the number of the signal that caused the kid to terminate
 124 int Kid::termSignal() const
 125 {
 126     return WTERMSIG(status);
 127 }
 128
 129 /// whether the process was terminated by a given signal
 130 bool Kid::signaled(int sgnl) const
 131 {
 132     return signaled() && (termSignal() == sgnl);
 133 }
 134
 135 /// returns kid name
 136 const String& Kid::name() const
 137 {
 138     return theName;
 139 }