Reverse logic of checking output in @inspectFile

This change makes @inspectFile in ModSecurity 3.x to operate in exact
the same way as it operates in ModSecurity 2.x, so existing helper scripts
like runav.pl [1] will work without any changes.

[1] https://github.com/SpiderLabs/owasp-modsecurity-crs/blob/v3.0/master/util/av-scanning/runav.pl

Author: defanator

src/operators/inspect_file.cc

@@ -73,10 +73,11 @@ bool InspectFile::evaluate(Transaction *transaction, const std::string &str) {
         pclose(in);
 
         res.append(s.str());
-        if (res.size() > 1 && res.at(0) == '1') {
-            return true;
+        if (res.size() > 1 && res.at(0) != '1') {
+            return true; /* match */
         }
 
+        /* no match */
         return false;
     }
 }