ros_sigint_handler.h

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#ifndef QB_DEVICE_SIGINT_HANDLER_H
#define QB_DEVICE_SIGINT_HANDLER_H
 
// specific for custom SIGINT handler
#include <signal.h>
#include <ros/xmlrpc_manager.h>
 
namespace ros_sigint_handler {
// signal-safe flag for whether shutdown is requested
static volatile sig_atomic_t g_request_shutdown = 0;
 
// replacement SIGINT handler
static void mySigIntHandler(int _) {
  (void)_;
  g_request_shutdown = 1;  // set flag
}
 
// replacement "shutdown" XMLRPC callback
static void shutdownCallback(XmlRpc::XmlRpcValue &params, XmlRpc::XmlRpcValue &result) {
  int num_params = 0;
  if (params.getType() == XmlRpc::XmlRpcValue::TypeArray) {
    num_params = params.size();
  }
  if (num_params > 1) {
    std::string reason = params[1];
    ROS_WARN("Shutdown request received. Reason: [%s]", reason.c_str());
    g_request_shutdown = 1;  // set flag
  }
 
  result = ros::xmlrpc::responseInt(1, "", 0);
}
 
int isShuttingDown() {
  return g_request_shutdown;
}
 
void overrideHandlers() {
  // override SIGINT handler
  signal(SIGINT, mySigIntHandler);
  // override XMLRPC shutdown
  ros::XMLRPCManager::instance()->unbind("shutdown");
  ros::XMLRPCManager::instance()->bind("shutdown", shutdownCallback);
}
}  // namespace ros_sigint_handler
 
#endif // QB_DEVICE_SIGINT_HANDLER_H