[Hamlib-developer] rigctl segfault

[Nate B. <n0...@ne...>]

I discovered a segfault while testing my ft890 code.  When I used the
's' command in rigctl's interactive mode it would print the "Split mode: "
string plus the value (0 or 1) and then segfaulted.  Looking at rigctl.c
I gathered the problem was related to the addition of tx_vfo last summer.

I had not played with this function since the tx_vfo parameter was added
to get_split_vfo, so that variable most likely contained garbage as
ft890.c wasn't assigning anything to the tx_vfo variable.

Looking at src/misc.c I see that the vfo_str structure is terminated by
{ RIG_VFO_NONE, NULL }, on line 351.  I changed it to {RIG_VFO_NONE, "" },
and then changed line 371 to test for "" instead of NULL in the for
loop test and then changed line 375 to return ""; instead of return
NULL;  After these changes the segmentation fault ceased.

I see several other structures in src/misc.c that have their last value,
usually XXX_XXX_NONE, using a pointer NULL instead of a string Nul ("").
Also, their associated functions test for NULL in a string context and
are probably just as vunerable.  According to my interpretation of K&R C, 
the two are not interchangable.  Thus, I propose modifying the rest of 
src/misc.c as above.

Thoughts?

73, de Nate >>

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