src/support/syscontr.C

   1 #include <config.h>
   2
   3 #include <cerrno>
   4 #include <cstdlib>
   5 #include <unistd.h>
   6 #include <sys/wait.h>
   7 #include "syscontr.h"
   8 #include "syscall.h"
   9 #include "debug.h"
  10
  11 #ifdef __GNUG__
  12 #pragma implementation
  13 #endif
  14
  15
  16 //
  17 // Default constructor
  18 //
  19
  20 SystemcallsSingletoncontroller::SystemcallsSingletoncontroller()
  21 {
  22        sysCalls = 0;
  23 }
  24
  25 //
  26 // Destructor
  27 //
  28 // destroy structs for leaving program
  29 // open question: should we stop childs here?
  30 // Asger says no: I like to have my xdvi open after closing LyX. Maybe
  31 // I want to print or something.
  32
  33 SystemcallsSingletoncontroller::~SystemcallsSingletoncontroller()
  34 {
  35        ControlledCalls *next;
  36        while (sysCalls)
  37        {
  38                next = sysCalls->next;
  39                delete sysCalls;
  40                sysCalls = next;
  41        }
  42
  43 }
  44
  45 //
  46 // Add child process information into controlled list
  47 //
  48
  49 void
  50 SystemcallsSingletoncontroller::addCall(Systemcalls const &newcall) {
  51        ControlledCalls * newCall = new ControlledCalls;
  52        if (newCall == 0) // sorry, no idea
  53                return;
  54        newCall->next = sysCalls;
  55        newCall->call = new Systemcalls(newcall);
  56        sysCalls = newCall;
  57 }
  58
  59 //
  60 // Timer-call
  61 //
  62 // Check list, if there is a stopped child. If yes, call-back.
  63 //
  64
  65 void
  66 SystemcallsSingletoncontroller::timer() {
  67         // check each entry of our list, if it's finished
  68         ControlledCalls *prev = 0;
  69         for (ControlledCalls *actCall= sysCalls; actCall; actCall= actCall->next)
  70         {
  71                 pid_t pid= actCall->call->getpid();
  72                 int stat_loc;
  73                 int waitrpid = waitpid(pid, &stat_loc, WNOHANG);
  74                 if (waitrpid == -1) {
  75                         lyxerr << "LyX: Error waiting for child:"
  76                                << strerror(errno) << endl;
  77                 } else if (WIFEXITED(stat_loc) || WIFSIGNALED(stat_loc)) {
  78                         if (WIFEXITED(stat_loc)) {
  79                                 // Ok, the return value goes into retval.
  80                                 actCall->call->setRetValue(WEXITSTATUS(stat_loc));
  81                         } else {
  82                                 // Child died, so pretend it returned 1
  83                                 actCall->call->setRetValue(1);
  84                         }
  85                         // Callback and release
  86                         actCall->call->callback();
  87                         if (actCall == sysCalls) {
  88                                 sysCalls = actCall->next;
  89                         } else {
  90                                 prev->next = actCall->next;
  91                         }
  92                         delete actCall;
  93                         actCall = prev;
  94                 } else if (WIFSTOPPED(stat_loc)) {
  95                         lyxerr << "LyX: Child (pid: " << pid
  96                                << ") stopped on signal "
  97                                << WSTOPSIG(stat_loc)
  98                                << ". Waiting for child to finish." << endl;
  99                 } else {
 100                         lyxerr << "LyX: Something rotten happened while "
 101                                 "waiting for child " << pid << endl;
 102                 }
 103                 prev = actCall;
 104         }
 105 }