void SIGCHLD_handler(int s)
{
int old_errno = errno;
int child_status = 0, child_pid = 0;
pid_t appmon_pid = getpid();
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: appmon_pid=%d =============>\n", appmon_pid);
while (1)
{
do
{
errno = 0;
//call waitpid trying to avoid suspend-related state changes.(no WUNTRACED or WCONTINUED options to waitpid)
child_pid = waitpid(WAIT_ANY, &child_status, WNOHANG);
} while (child_pid <= 0 && errno == EINTR);
if (child_pid <= 0)
{
/* A real failure means there are no more
stopped or terminated child processes, so return. */
errno = old_errno;
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: pid=%d =============< quit\n", appmon_pid);
fflush(stdout);
return;
}
app_t* app = find_by_pid(child_pid);
if (NULL != app)
{
int exited = WIFEXITED(child_status);
int exited_code = exited ? WEXITSTATUS(child_status) : -1;
int signaled = WIFSIGNALED(child_status);
//update exit status only if process is terminated.
//if stopped/continued event on process is caught, don't update status
if (!exited && !signaled)
{
SWI_LOG("APPMON", ERROR, "SIGCHLD_handler: status change looks like suspend events (STOP/CONT), ignored\n");
continue; //go to next waipid call
}
//real child termination, update values
app->last_exit_code = child_status;
app_exit_status(app);
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: app terminated: id=%d, prog=%s was pid %d, calculated status =%s\n",
app->id, app->prog, child_pid, app->last_exit_status);
if (TO_BE_KILLED == app->status || (STARTED == app->status && exited && !exited_code))
{
//put flag to be used it stop_app
app->status = KILLED;
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: status => KILLED\n");
}
else
{
if ((exited && exited_code > 0) | signaled)
{
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: Child status error %d, application is set to TO_BE_RESTARTED, %s\n",
child_status, app->prog);
//error has occur, restart app after delay
// app will not be found if it has been stopped voluntarily, so it won't be restarted.
app->status = TO_BE_RESTARTED;
alarm(RESTART_DELAY);
}
}
}
else //app == NULL, pid not found in monitored apps
{
SWI_LOG("APPMON", DEBUG, "SIGCHLD_handler: unknown dead app, pid=%d\n", child_pid);
}
}
}
//handler para tratar SIGCHLD
static void sigchld_hand(int signo, siginfo_t *info, void *data) {
waitpid(info->si_pid, NULL, 0);
vector_remove(job_list, find_by_pid(job_list, info->si_pid));
}
void* remove_by_pid(Vector vector, pid_t pid){
return vector_remove(vector, find_by_pid(vector, pid));
}