OS functions available for user code?

makerken · January 28, 2019, 5:19pm

Looking at encoding/decoding JSON on a Particle device.
Currently best practice as I understand it is using a char[] and encoding with snprintf() or use a library.

I looked to see what the firmware was using, and seems like there is already a very nice function do to that.
So any way to access system os firmware functions? Excluding the possibility of building and flashing your own firmware. Security and reliability, would be two good encompassing reasons that you can’t.

If no, exposing the JSON decoding/encoding seems useful, but beyond my ability to contribute.

github.com

particle-iot/device-os/blob/27f6c3884e2b6786ff5bfcc4546cd731d555a7d3/hal/src/photon/softap.cpp#L168


    * @param writer    The writer that receives the result of the command.
    * @return  A command response code. By convention 0 indicates success.
    */
   virtual int execute(Reader& reader, Writer& writer)=0;
};


/**
* Base class for commands whose requests and responses are encoded using
* json.
*/
class JSONCommand : public Command {


protected:


   jsmntok_t * json_tokenise(char *js)
   {
       jsmn_parser parser;
       parser.size = sizeof(parser);
       jsmn_init(&parser, NULL);


       unsigned int n = 64;

github.com

particle-iot/device-os/blob/27f6c3884e2b6786ff5bfcc4546cd731d555a7d3/services/src/jsmn.c#L328


       }
   }


   return count;
}


/**
* Creates a new parser based over a given  buffer with an array of tokens
* available.
*/
void jsmn_init(jsmn_parser *parser, void* reserved) {
   parser->pos = 0;
   parser->toknext = 0;
   parser->toksuper = -1;
}

rickkas7 · January 28, 2019, 5:22pm

jsmn is not available to user applications.

You might be interested in this library, which is a wrapper around jsmn which makes it much easier to use and is much more memory-efficient than SparkJson/ArduinoJson.

makerken · January 28, 2019, 5:29pm

Thanks

As everything gets better and faster, I don’t have to optimize every byte out so having a function/class twice is not going to affect actual use. I am still adjusting.

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OS functions available for user code?

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