[Hamlib-developer] ATS Mini backend (44001) segfault in p_ats_update_state() with firmware 2.35

[Olav R. <ol...@ol...>]

Hello,

I found a reproducible segmentation fault in the new ATS Mini
Hamlib backend (model 44001) on macOS.

Environment:
- macOS, 64-bit
- ATS Mini firmware 2.35
- Hamlib 5.0.0~git 2026-08-23
- commit 45755bebf
- /dev/cu.usbmodem14201
- 115200 baud

The ATS Mini returns monitor responses such as:

235,14074,0,0,ALL,USB,1k,3.0k,0,40,27,0,1,4.86,47

Frequency and mode control otherwise work.

When using rigctld, it can eventually crash with EXC_BAD_ACCESS.
An LLDB backtrace shows:

strtod
p_ats_update_state() at ats.c:97:38
ats_mini_get_freq() at ats.c:383:15
rig_get_freq()
rig_set_freq()
rigctl_set_freq()
rigctl_parse()
handle_socket()

The immediate fault is in strtod(), apparently while parsing a
monitor response. It looks like p_ats_update_state() can pass a
NULL/invalid token to the numeric parser if the response is
incomplete or otherwise unexpected.

I have the complete -vvvvv rigctld output and LLDB backtrace
available if useful.

This is the best part:

* thread #3, stop reason = EXC_BAD_ACCESS (code=1, address=0x0)
  * frame #0: ... libsystem_c.dylib`fastParse64
    frame #1: ... `_ffpp_strtoencf64_l`
    frame #2: ... `strtod`
    frame #3: ... libhamlib.5.dylib`p_ats_update_state(rig=...) at ats.c:97:38
    frame #4: ... `ats_mini_get_freq(...)` at ats.c:383:15
    frame #5: ... `rig_get_freq(...)` at rig.c:2687:19
    frame #6: ... `rig_set_freq(...)` at rig.c:2452:23
    frame #7: ... `rigctld` ... `rigctl_set_freq(...)`
    frame #8: ... `rigctld` ... `rigctl_parse(...)`
    frame #9: ... `rigctld` ... `handle_socket(...)`

vy 73,
Olav
DG3BP