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0 pointsGibbon14y ago0 comments

I do that a lot with the firmware I write in C.

  typedef struct
  {
    err_t error;
    int error_line;
    char *error_msg;
    ...
    ...
  } thing_t;

  // set out of range error
  thing->error = THING_ERROR_OOR;
  thing->error_line = __LINE__;
  thing->error_msg = "outofrange"

You can grep on 'outofrange' and find where the error was set.

I originally started doing that to mark 'bad' analog readings in process control equipment. I wrote my filters and control loops to be able to 'eat' occasional bad readings without barfing. Worked very well.

0 comments

Const-me4y ago

I often using something like this in C++

    if( nullptr != pfnErrorSink )
        pfnErrorSink( "outofrange", __FILE__, __LINE__ );
    return E_BOUNDS; // Or sometimes throw E_BOUNDS;

Where pfnErrorSink is either global, thread_local or a field keeping C function pointer provided by whoever consumes the code.

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