Follow-up to #881. cbm_build_win_cmdline() returned false from inside its loop on
buffer overflow without NUL-terminating buf, although its header contract states the
buffer holds a string. No live bug — both call sites (cbm_run_win and the UI
http_server index spawn) ignore buf when the function returns false — but a future
caller trusting the documented contract could read an unterminated (possibly
uninitialized) buffer. Set buf[0]='\0' on the overflow path so it is always a valid
string, and correct the header comment to match.
Reproduce-first: the new win_cmdline_overflow_leaves_empty_string test feeds an argv
that overflows a small cap and asserts buf[0]=='\0'. It is RED on the pre-fix code
(buf[0] holds the first quoted byte '"' = 0x22) and GREEN with the fix.
Also tidies two review nits in the same files:
- fix the stale cbm_cmdline_put comment (it returns pos UNCHANGED on overflow;
the overflow is signalled via *ovf, not an advancing pos),
- bounds-guard the reference CommandLineToArgvW parser in the round-trip test.
Refs: #881
Signed-off-by: Flipper <jacobphilipp@ymail.com>
Flipper
a57d8e3e9b