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#include <config.h>
#ifdef __GNUG__
#pragma implementation
#endif
#include <sys/types.h>
#include <sys/wait.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include "syscall.h"
#include "syscontr.h"
//----------------------------------------------------------------------
// Class, which controlls a system-call
//----------------------------------------------------------------------
// constructor
Systemcalls::Systemcalls()
{
pid = (pid_t) 0; // yet no child
}
// constructor
//
// starts child
Systemcalls::Systemcalls(Starttype how, LString what, Callbackfct cback)
{
start = how;
command = what;
cbk = cback;
pid = (pid_t) 0; // no child yet
retval = 0;
Startscript();
}
// destructor
// not yet implemented (?)
Systemcalls::~Systemcalls()
{
}
// Start a childprocess
//
// if child runs in background, add information to global controller.
int Systemcalls::Startscript()
{
retval = 0;
switch (start) {
case System:
retval = system(command.c_str());
Callback();
break;
case Wait:
pid = Fork();
if (pid>0) { // Fork succesful. Wait for child
waitForChild();
Callback();
} else
retval = 1;
break;
case DontWait:
pid=Fork();
if (pid>0) {
// Now integrate into Controller
SystemcallsSingletoncontroller::Startcontroller starter;
SystemcallsSingletoncontroller *contr=
starter.GetController();
// Add this to contr
contr->AddCall(*this);
} else
retval = 1;
break;
//default: // error();
//break;
}
return retval;
}
// Wait for child process to finish. Returns returncode from child.
void Systemcalls::waitForChild()
{
// We'll pretend that the child returns 1 on all errorconditions.
retval = 1;
int status;
bool wait = true;
while (wait) {
pid_t waitrpid = waitpid(pid, &status, WUNTRACED);
if (waitrpid == -1) {
perror("LyX: Error waiting for child");
wait = false;
} else if (WIFEXITED(status)) {
// Child exited normally. Update return value.
retval = WEXITSTATUS(status);
wait = false;
} else if (WIFSIGNALED(status)) {
fprintf(stderr,"LyX: Child didn't catch signal %d "
"and died. Too bad.\n", WTERMSIG(status));
wait = false;
} else if (WIFSTOPPED(status)) {
fprintf(stderr,"LyX: Child (pid: %ld) stopped on "
"signal %d. Waiting for child to finish.\n",
(long) pid, WSTOPSIG(status));
} else {
fprintf(stderr,"LyX: Something rotten happened while "
"waiting for child %ld\n", (long) pid);
wait = false;
}
}
}
// generate child in background
pid_t Systemcalls::Fork()
{
pid_t cpid=fork();
if (cpid == 0) { // child
LString childcommand(command); // copy
LString rest = command.split(childcommand, ' ');
const int MAX_ARGV = 255;
char *syscmd = NULL;
char *argv[MAX_ARGV];
int index = 0;
bool Abbruch;
do {
if (syscmd == NULL) {
syscmd = childcommand.copy();
}
argv[index++] = childcommand.copy();
// reinit
Abbruch = !rest.empty();
if (Abbruch)
rest = rest.split(childcommand, ' ');
} while (Abbruch);
argv[index] = NULL;
// replace by command. Expand using PATH-environment-var.
execvp(syscmd, argv);
// If something goes wrong, we end up here:
perror("LyX: execvp failed");
} else if (cpid < 0) { // error
perror("LyX: Could not fork");
} else { // parent
return cpid;
}
return 0;
}
// Reuse of instance
int Systemcalls::Startscript(Starttype how, LString what, Callbackfct cback)
{
start = how;
command = what;
cbk = cback;
pid = (pid_t) 0; // yet no child
retval = 0;
return Startscript();
}
//
// Mini-Test-environment for script-classes
//
#ifdef TEST_MAIN
#include <stdio.h>
int SimulateTimer;
void back(LString cmd, int retval)
{
printf("Done: %s gave %d\n", cmd.c_str(), retval);
SimulateTimer = 0;
}
int main(int, char**)
{
SystemcallsSingletoncontroller::Startcontroller starter;
SystemcallsSingletoncontroller *contr=starter.GetController();
Systemcalls one(Systemcalls::System, "ls -ltag", back);
Systemcalls two(Systemcalls::Wait, "ls -ltag", back);
SimulateTimer = 1;
Systemcalls three(Systemcalls::DontWait , "ls -ltag", back);
// Simulation of timer
while (SimulateTimer)
{
sleep(1);
contr->Timer();
}
}
#endif
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