Fix for keepalive issue #445

[sm-shaw]

Fixes issue #445 where keepalive time is not detected if either are zero and adds user configurable keepalive time.
Also fixes issue with vucreate automatically running loadscript if script is not already loaded.

[memmertoIBM]

The if and else branches do the same thing - do we need the condition at all?

[sm-shaw]

I believe so - the genericdict has a new entry as below in the XML config files and this also gets stored in the SQLite files as well.

<commandline>
       <keepalive_margin>10</keepalive_margin>
</commandline>

all of the XML files get stored as global dicts on startup, upvar allows us to access this dict on a higher level.
The user could potentially corrupt this entry by editing the file so either it will not be there, or it could not be set to a valid integer that we can do calculations with. So the first if/else checks if there is an entry in the genericdict before we start to use it, otherwise it would give an uncaught error so instead in this case it gets set to a default of 10. (This would also happen if the XML is updated but not the SQLite files) If the first is passed and an entry is found the 2nd if/else then checks if this is a valid integer (https://core.tcl-lang.org/tips/doc/trunk/tip/395.md) if it is not (![string is entier $ka_margin]) e.g. someone changed the entry to "true" misunderstanding the value, then it also gets set to a default of 10.

We can potentially compress this to use an && for the 2 statements as Tcl will short circuit if the first argument (exists) is not true so will not evaluate the 2nd (is entier - instead of is not entier) - however doing this you need to know Tcl does this - so as it stands is safer as if you reversed the 2 && arguments and the dict entry didn't exist but was evaluated 2nd it would give an uncaught error.

[memmertoIBM]

I understand now. I had misread the code.

I thought the else on line 1062 was for the if on line 1061, but it's actually for the if on line 1059.

Can we fix the indentation on lines 1062-1064 so that it is aligned properly with line 1059?

[sm-shaw]

I have updated the indentation. There is a package included with HammerDB called reformat_tcl. You can do "package require reformat_tcl" and then reformat_src indent filename, and it will update the file with the correct indentation. This should server as a prompt for me to use it to prevent less confusion going forward.

[sm-shaw]

finish review

[sm-shaw]

I believe so - the genericdict has a new entry as below in the XML config files and this also gets stored in the SQLite files as well.

<commandline>
       <keepalive_margin>10</keepalive_margin>
</commandline>

all of the XML files get stored as global dicts on startup, upvar allows us to access this dict on a higher level.
The user could potentially corrupt this entry by editing the file so either it will not be there, or it could not be set to a valid integer that we can do calculations with. So the first if/else checks if there is an entry in the genericdict before we start to use it, otherwise it would give an uncaught error so instead in this case it gets set to a default of 10. (This would also happen if the XML is updated but not the SQLite files) If the first is passed and an entry is found the 2nd if/else then checks if this is a valid integer (https://core.tcl-lang.org/tips/doc/trunk/tip/395.md) if it is not (![string is entier $ka_margin]) e.g. someone changed the entry to "true" misunderstanding the value, then it also gets set to a default of 10.

We can potentially compress this to use an && for the 2 statements as Tcl will short circuit if the first argument (exists) is not true so will not evaluate the 2nd (is entier - instead of is not entier) - however doing this you need to know Tcl does this - so as it stands is safer as if you reversed the 2 && arguments and the dict entry didn't exist but was evaluated 2nd it would give an uncaught error.

[sm-shaw]

requested changes to indentation added.

[abondvt89]

Merging after reviews and approval of the three members of the code maintenance team.