GcodeDispatch.cpp

/*
      This file is part of Smoothie (http://smoothieware.org/). The motion control part is heavily based on Grbl (https://github.com/simen/grbl).
      Smoothie is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
      Smoothie is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
      You should have received a copy of the GNU General Public License along with Smoothie. If not, see <http://www.gnu.org/licenses/>.
*/

#include <string>
using std::string;
#include "libs/Module.h"
#include "libs/Kernel.h"
#include "utils/Gcode.h"
#include "libs/nuts_bolts.h"
#include "GcodeDispatch.h"
#include "modules/robot/Conveyor.h"
#include "libs/SerialMessage.h"
#include "libs/StreamOutput.h"

GcodeDispatch::GcodeDispatch(){}

// Called when the module has just been loaded
void GcodeDispatch::on_module_loaded() {
    return_error_on_unhandled_gcode = this->kernel->config->value( return_error_on_unhandled_gcode_checksum )->by_default(false)->as_bool();
    this->register_for_event(ON_CONSOLE_LINE_RECEIVED);
    currentline = -1;
}

// When a command is received, if it is a Gcode, dispatch it as an object via an event
void GcodeDispatch::on_console_line_received(void * line){
    SerialMessage new_message = *static_cast<SerialMessage*>(line);
    string possible_command = new_message.message;

    char first_char = possible_command[0];
    int ln = 0;
    int cs = 0;
    if( first_char == 'G' || first_char == 'M' || first_char == 'T' || first_char == 'N' ){

        //Get linenumber
        if( first_char == 'N' ){
            Gcode full_line = Gcode(possible_command, new_message.stream);
            ln = (int) full_line.get_value('N');
            int chksum = (int) full_line.get_value('*');

            //Catch message if it is M110: Set Current Line Number
            if( full_line.has_letter('M') ){
                if( ((int) full_line.get_value('M')) == 110 ){
                    currentline = ln;
                    new_message.stream->printf("ok\r\n");
                    return;
                }
            }

            //Strip checksum value from possible_command
            size_t chkpos = possible_command.find_first_of("*");
            possible_command = possible_command.substr(0, chkpos);
            //Calculate checksum
            if( chkpos != string::npos ){
                for(auto c = possible_command.cbegin(); *c != '*' && c != possible_command.cend(); c++)
                    cs = cs ^ *c;
                cs &= 0xff;  // Defensive programming...
                cs -= chksum;
            }
            //Strip line number value from possible_command
            size_t lnsize = possible_command.find_first_not_of("N0123456789.,- ");
            possible_command = possible_command.substr(lnsize);

        }else{
            //Assume checks succeeded
            cs = 0x00;
            ln = currentline + 1;
        }

        //Remove comments
        size_t comment = possible_command.find_first_of(";(");
        if( comment != string::npos ){ possible_command = possible_command.substr(0, comment); }

        //If checksum passes then process message, else request resend
        int nextline = currentline + 1;
        if( cs == 0x00 && ln == nextline ){
            if( first_char == 'N' ) {
                currentline = nextline;
            }

            while(possible_command.size() > 0) {
                size_t nextcmd = possible_command.find_first_of("GMT", possible_command.find_first_of("GMT")+1);
                string single_command;
                if(nextcmd == string::npos) {
                    single_command = possible_command;
                    possible_command = "";
                }
                else {
                    single_command = possible_command.substr(0,nextcmd);
                    possible_command = possible_command.substr(nextcmd);
                }
                //Prepare gcode for dispatch
                Gcode* gcode = new Gcode(single_command, new_message.stream);
                gcode->prepare_cached_values();

//                 printf("dispatch %p: '%s' G%d M%d...", gcode, gcode->command.c_str(), gcode->g, gcode->m);
                //Dispatch message!
                this->kernel->call_event(ON_GCODE_RECEIVED, gcode );
                if (gcode->add_nl)
                    new_message.stream->printf("\r\n");

                if ( return_error_on_unhandled_gcode == true && gcode->accepted_by_module == false)
                    new_message.stream->printf("ok (command unclaimed)\r\n");
                else if(!gcode->txt_after_ok.empty()) {
                    new_message.stream->printf("ok %s\r\n", gcode->txt_after_ok.c_str());
                    gcode->txt_after_ok.clear();
                }else
                    new_message.stream->printf("ok\r\n");

                delete gcode;
            
            }
        }else{
            //Request resend
            new_message.stream->printf("rs N%d\r\n", nextline);
        }

    // Ignore comments and blank lines
    }else if( first_char == ';' || first_char == '(' || first_char == ' ' || first_char == '\n' || first_char == '\r' ){
        new_message.stream->printf("ok\r\n");
    }
}