Re: [Tlf-devel] TLF-1.3.1 early pre release

[Thomas Beierlein]

Hi Ervin,

finally I find time to answer. Sorry for the delay.

Am Sat, 13 Oct 2018 18:15:22 +0200
schrieb Ervin Hegedüs <address@hidden>:
> > There is still one problem with your solution which you should sort
> > out: fldigi_get_log_call() is called from background_process which
> > runs as a separate thread parallel to the logging front end
> > function logit(). That may be ok for just polling fldigi and
> > displaying the received text in the rtty window. But for
> > manipulating hiscall and displaying the according country
> > information it may result in problems as both - your function and
> > callinput() may manipulate the same data.  
> 
> yes, it's clear for me (now...).
> 
> > Furthermore neither getctydata() nor searchlog() are checked to be
> > threadsafe, so calling it from the background thread may be
> > problematic.  
> 
> as I see, both function called from different threads - without
> fldigi_get_log_call(), so we have to review anyway.
>  
Ok, have not seen it. Thanks, I will look for that.

> > I have added the code as is to get forward with the 1.3.1 release
> > but you should sort out the problems in next time.  
> 
> ok - what should we do? After first and quick review I thought we
> can make a new function in callinput.c, called sethiscall(),
> which waits a string, and sets the hiscall. All other function in
> different threads collects the callsign in a local buffer, and
> call this function. This new function should rentrant and thread
> safe... any idea?
> 
I think there is a better way. Copy the call in fldigi_get_log_call()
into an intermediate buffer and set a flag. During callinput() we pick
that up and bring it to hiscall. The access to the buffer can be
protected by a mutex and so made thread safe.

The advantage in these scheme is that we have control when we change
hiscall. Otherwise it may be possible that fldigi_get_log_call() does
change it during some unrelated operation (e.g. writing the last QSO to
disk or similar).

73, de Tom DL1JBE

-- 
"Do what is needful!"
Ursula LeGuin: Earthsea
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