task: disallow task mode change if jogging

Realtime mpg (wheel) jogging is not controlled through task,
so task must detect jogging status provided by motion
to disallow a task mode change

Ref:
https://forum.linuxcnc.org/24-hal-components/45991-jogwheel-start-of-any-gcode-motion-causes-following-error#243898

src/emc/motion/control.c

@@ -302,6 +302,27 @@ void emcmotController(void *arg, long period)
    prototypes"
 */
 
+bool axis_jog_is_active(void)
+{
+    int n;
+    for (n = 0; n < EMCMOT_MAX_AXIS; n++) {
+        if ( (&axes[n])->kb_ajog_active || (&axes[n])->wheel_ajog_active) {
+            return true;
+        }
+    }
+    return false;
+}
+
+bool joint_jog_is_active(void)
+{
+    int n;
+    for (n = 0; n < EMCMOT_MAX_JOINTS; n++) {
+        if ( (&joints[n])->kb_jjog_active ||  (&joints[n])->wheel_jjog_active) {
+            return true;
+        }
+    }
+    return false;
+}
 static void process_inputs(void)
 {
     int joint_num, spindle_num;
@@ -2166,6 +2187,8 @@ static void update_status(void)
     /* check to see if we should pause in order to implement
        single emcmotDebug->stepping */
 
+    emcmotStatus->jogging_active =  axis_jog_is_active()
+                                 || joint_jog_is_active();
     if (emcmotDebug->stepping && emcmotDebug->idForStep != emcmotStatus->id) {
       tpPause(&emcmotDebug->coord_tp);
       emcmotDebug->stepping = 0;

src/emc/motion/motion.h

@@ -78,6 +78,7 @@ to another.
 #include "kinematics.h"
 #include "simple_tp.h"
 #include "rtapi_limits.h"
+#include "rtapi_bool.h"
 #include <stdarg.h>
 
 
@@ -738,7 +739,7 @@ Suggestion: Split this in to an Error and a Status flag register..
 	unsigned char tail;	/* flag count for mutex detect */
 	int external_offsets_applied;
 	EmcPose eoffset_pose;
-        
+    bool jogging_active;
     } emcmot_status_t;
 
 /*********************************

src/emc/nml_intf/emc_nml.hh

@@ -1222,6 +1222,7 @@ class EMC_MOTION_STAT:public EMC_MOTION_STAT_MSG {
     int on_soft_limit;
     int external_offsets_applied;
     EmcPose eoffset_pose;
+    bool jogging_active;
 };
 
 // declarations for EMC_TASK classes

src/emc/task/emctask.cc

@@ -231,6 +231,11 @@ int emcTaskSetMode(int mode)
 {
     int retval = 0;
 
+    if (jogging_is_active()) {
+        emcOperatorError(0, "Ignoring task mode change while jogging");
+        return 0;
+    }
+
     switch (mode) {
     case EMC_TASK_MODE_MANUAL:
 	// go to manual mode

src/emc/task/emctaskmain.cc

@@ -154,6 +154,10 @@ int all_homed(void) {
     return 1;
 }
 
+bool jogging_is_active(void) {
+    return emcStatus->motion.jogging_active;
+}
+
 void emctask_quit(int sig)
 {
     // set main's done flag

src/emc/task/task.hh

@@ -27,6 +27,7 @@ extern int emcRunHalFiles(const char *filename);
 
 // Returns 0 if all joints are homed, 1 if any joints are un-homed.
 int all_homed(void);
+bool jogging_is_active(void);
 
 int emcTaskInit();
 int emcTaskHalt();

src/emc/task/taskintf.cc

@@ -1968,6 +1968,8 @@ int emcMotionUpdate(EMC_MOTION_STAT * stat)
 	stat->analog_output[aio] = emcmotStatus.analog_output[aio];
     }
 
+    stat->jogging_active = emcmotStatus.jogging_active;
+
     // set the status flag
     error = 0;
     exec = 0;