Added new functions, modified argument types, fixed typo

[aquaticus]

• const char* oid instead of char* oid as argument
• use const string& instead of string
• New dynamic handlers that accepts function pointer as an argument:
  • addDynamicIntegerHandler()
  • addDynamicReadOnlyTimestampHandler()
  • addDynamicReadOnlyStringHandler()
• Handler to accept int (not only int*)
• Fixed typo in guage to gauge (as in spec). addGugeHandler() marked as depreciated (new function addGaugeHandler()).
• minor fixes in variable names to satisfy clang-tidy
• Version bumped to 2.1.0

[0neblock]

Thanks heaps for your PR!
The changes look good, I'm just not sure about the change to const char* for the OID handlers.
Do you have thoughts on this?

[0neblock]

I believe making the oid a const char* will remove the ability to dynamically create OID's when setting up the agent.
I have some projects where I need to dynamically create OID handlers on the fly, that are not known at compile time, so I think this will need to stay as char *.
Thoughts?

[aquaticus]

The compiler automatically converts char* to const char*. This is absolutely safe and acceptable (you won't get compilation error). You can pass both const strings and non-const char tables to function with const char* argument.

Opposite (const char* to char*) is treated as an error by any modern compiler (unless you cast to char*).
With const char* oid type both usages are valid:

// non-const dynamic string
char tmp[32];
sprintf(tmp, "Hello");
addOpaqueHandler(tmp,...); //OK

// const string
addOpaqueHandler("Hello",...); //OK

The only scenario you would like char* oid type is when the function modifies oid. As far as I know this is not the case (correct me if I'm wrong).

[0neblock]

Ah of course, You've quite right. Sorry I clearly had a brain fart.
Thanks for the detailed explanation!

[0neblock]

Thanks A lot for this contribution, it looks great.
Just going to try and get the CI tests to run on this branch before it is merged, to make sure the tests pass.
I'm going to close & re-open this to try to trigger the CI workflow to run.

[0neblock]

Need to fix the CI tests, but I ran locally and things look good.
Thanks again for these changes, appreciated!