[PATCH v2 09/20] rv/rvgen: fix DOT file validation logic error

[Wander Lairson Costa <wander@redhat.com>]

Fix incorrect boolean logic in automata DOT file format validation
that allowed malformed files to pass undetected. The previous
implementation used a logical AND operator where OR was required,
causing the validation to only reject files when both the first
token was not "digraph" AND the second token was not
"state_automaton". This meant a file starting with "digraph" but
having an incorrect second token would incorrectly pass validation.

The corrected logic properly rejects DOT files where either the
first token is not "digraph" or the second token is not
"state_automaton", ensuring that only properly formatted automaton
definition files are accepted for processing. Without this fix,
invalid DOT files could cause downstream parsing failures or
generate incorrect C code for runtime verification monitors.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Reviewed-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
---
 tools/verification/rvgen/rvgen/automata.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/verification/rvgen/rvgen/automata.py b/tools/verification/rvgen/rvgen/automata.py
index deb1f09556c3c..38035d59cdd51 100644
--- a/tools/verification/rvgen/rvgen/automata.py
+++ b/tools/verification/rvgen/rvgen/automata.py
@@ -59,7 +59,7 @@ class Automata:
         # checking the first line:
         line = dot_lines[cursor].split()
 
-        if (line[0] != "digraph") and (line[1] != "state_automaton"):
+        if (line[0] != "digraph") or (line[1] != "state_automaton"):
             raise AutomataError(f"Not a valid .dot format: {self.__dot_path}")
         else:
             cursor += 1
-- 
2.52.0