Unable to load misra rules file from the command line

[Grahame White]

I built the tagged 1.87 release of cppcheck on a linux machine using the

make -j 8 SRCDIR=build CFGDIR=/usr/share/cppcheck/cfg HAVE_RULES=yes CXXFLAGS="-O2 -DNDEBUG -Wall -Wno-sign-compare -Wno-unused-function -lpcre" install

Aside from a few warnings, the build was succesful and I'm able to run cppcheck against a test C project

However, when I wanted to add in the MISRA-C 2012 checks things don't go quite as smoothly.
I'm calling cppcheck using the following commandline options from the root of my test C project, as per this topic.

cppcheck -j 4 --enable=all --inconclusive --xml --xml-version=2 --rule-file=misra_rules.txt .

The only output I get from this is

cppcheck: error: unable to load rule-file: misra_rules.txt

My misra_rules.txt file looks something like:

Appendix A Summary of guidelines
Dir 1.1
Directive 1.1 Required - blah blah blah
Dir 2.1
Directive 2.1 Required - waffle waffle waffle

From a Windows machine, using the GUI version of cppcheck, this same exact same file works as expected

I had a look at cmdlineparser.cpp, specifically:

            // Rule file
            else if (std::strncmp(argv[i], "--rule-file=", 12) == 0) {
                tinyxml2::XMLDocument doc;
                if (doc.LoadFile(12+argv[i]) == tinyxml2::XML_SUCCESS) {
                    tinyxml2::XMLElement *node = doc.FirstChildElement();
                    for (; node && strcmp(node->Value(), "rule") == 0; node = node->NextSiblingElement()) {
                        Settings::Rule rule;

                        tinyxml2::XMLElement *tokenlist = node->FirstChildElement("tokenlist");
                        if (tokenlist)
                            rule.tokenlist = tokenlist->GetText();

                        tinyxml2::XMLElement *pattern = node->FirstChildElement("pattern");
                        if (pattern) {
                            rule.pattern = pattern->GetText();
                        }

                        tinyxml2::XMLElement *message = node->FirstChildElement("message");
                        if (message) {
                            tinyxml2::XMLElement *severity = message->FirstChildElement("severity");
                            if (severity)
                                rule.severity = Severity::fromString(severity->GetText());

                            tinyxml2::XMLElement *id = message->FirstChildElement("id");
                            if (id)
                                rule.id = id->GetText();

                            tinyxml2::XMLElement *summary = message->FirstChildElement("summary");
                            if (summary)
                                rule.summary = summary->GetText() ? summary->GetText() : "";
                        }

                        if (!rule.pattern.empty())
                            mSettings->rules.push_back(rule);
                    }
                } else {
                    printMessage("cppcheck: error: unable to load rule-file: " + std::string(12+argv[i]));
                    return false;
}

It's not clear, from a cursorary look, what the magic number 12 is all about but it does appear that it's trying to run my misra-rules.txt file through an XML parser, which doesn't make much sense to me. I'm guessing I must be missing something obvious.

[versat]

The Cppcheck parameter --rule-file has nothing to do with the Misra rule file.
The Misra rule texts file can not be specified as a Cppcheck parameter but as a Misra addon parameter.
For using the Addons via command line please see the chapter "Using Cppcheck addons" in the manual (http://cppcheck.sourceforge.net/manual.pdf). The Misra addon script is misra.py
The rule texts file can be specified as a parameter (IIRC it is --rule-texts) to this addon script.
See "Chapter 8. Misra" for more details.
Sadly there is no simpler way to run the addons at the moment.

I hope this helps. If the manual is not clear enough or you have further questions don't hesitate to ask.

[Grahame White]

Thanks for your reply, that was very helpful.

Unfortunately, I did not find Chapter 8 of the manual to be as helpful as it could be.
It does explain nicely how to process the MISRA C pdf to generate a usable text file.
It doesn't explain clearly how to run the misra plugin (or any other plug in for that matter)
* I didn't find it all that clear that the main cppcheck code was unable to trigger the addons.

Once I've got things working from my end I'll take a look at writing something for inclusion in the manual.

[versat]

Yes Chapter 8 is not really complete. Maybe a reference to the chapter explaining how addons work should be added there so this important information would be easier to find.
I am also not sure if this "pdftotext" process is really necessary. I just marked the relevant text, copied it and pasted it into a text file. Maybe pdftotext avoids some encoding / decoding problems, not sure about this.

I am happy that i was able to help a bit and it would be great if you could improve the manual.
The "source" for the manual is now a MarkDown file so it should be easy to enhance it:
https://github.com/danmar/cppcheck/blob/master/man/manual.md