fix: Allow inline comments in clamd.conf

[userwiths]

This PR attempts to resolve the issue mentioned in #1175

1. Regex has been changed in order to allow matching a given line even if it has a comment (separated with space or not) from the main expression.
2. When passing through an argument, check if it contains the comment character # and if it does, try to get the content on its left side.

Thoughts:

1. I have some doubts strtok is the best choice.
2. Another approach, better imo, would be to get the first match from the regex expression. I failed to find an example in the project where cli_regexec returns the made matches (most likely in the 4th argument, but it seems its used mostly with NULL through out the project).

[val-ms]

Thanks for the PR! I will try to review this after we have things lined up to publish 1.4.0, or after 1.4.0 ships.

[val-ms]

I rebased this PR to re-run the tests.

I found just minor clang-format issues.

In manual testing, I found that for string-based options (vs bool, size, or number args) -- spaces before a # end up getting included in the option value.

For example, I tried this for freshclam.conf:

DatabaseMirror http://localhost:8000 # database.clamav.net

The result was that it tried to download daily.cvd from:
http://localhost:8000 /daily.cvd (with a space in the middle).

I would have to remove the space between 8000 and # to make it work. Like this:

DatabaseMirror http://localhost:8000# database.clamav.net

But this doesn't look very natural and is bound to get complaints from users that try this feature.

I also had trouble with getting a bool to work. I tried this in freshclam.conf, but it didn't enable verbose mode:

LogVerbose yes #no

[userwiths]

Yeah, the clang-format I probably forgot about, now it should be formated as its supposed to.
I expected the tests to fail with the issue about spaces after arg, but on second thought there were no inline comments in the tests, currently added trimming of trailing spaces

Tried to see how I could implement a test for this fix, but I'm not sure if its possible to printout the options even in debug mode, as its managed in libclamav and not here.

Other caveat

If someone has # as a part of his option (dont know how viable that is, as a part of directory/file name for example) it would probably break their config too.

[val-ms]

Thanks for fixing the clang-format issue and also the trailing spaces issue. I tried a variety of variations of trailing spaces for options with strings, booleans, numbers. As far as I can tell it works nicely.

I am seeing a warning with this change when building:

/home/micah/dev/clamav/clamav-1/common/optparser.c: In function ‘optparse’:
/home/micah/dev/clamav/clamav-1/common/optparser.c:1195:35: warning: passing argument 1 of ‘strtok’ discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
 1195 |             arg          = strtok(arg, "#");
      |                                   ^~~
In file included from /home/micah/dev/clamav/clamav-1/common/optparser.c:36:
/usr/include/string.h:336:14: note: expected ‘char * __restrict__’ but argument is of type ‘const char *’
  336 | extern char *strtok (char *__restrict __s, const char *__restrict __delim)
      |              ^~~~~~
/home/micah/dev/clamav/clamav-1/common/optparser.c:1196:26: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
 1196 |             trim_comment = arg + strlen(arg) - 1;
      |                          ^

I took the liberty of fixing this and extending your change to also trim trailing tabs. I tidied the commits and rebased them with main so we've got all the latest commits in the branch. Pending a good run through GitHub Actions and Jenkins, I'm happy with this and will merge it.

[val-ms]

Thanks again for your work on this!