Some kind of comments are recognized by gcc7 but they are ignored with
-Wimplicit-fallthrough=5 and only attributes disable the warning.

Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>

Autotools does not generate defines in conditional way (ifndef .. define)
and therefore it might happen that "defines" in config.h migt redefine
some macros in different way and generate a warning.

e.g.
  In file included from /home/build/sssd/src/util/util.h:24:0,
                   from /home/build/sssd/src/python/pyhbac.c:24:
  ./config.h:322:0: error: "HAVE_LONG_LONG" redefined [-Werror]
   #define HAVE_LONG_LONG 1

  In file included from /usr/include/python3.6m/Python.h:50:0,
                   from /home/build/sssd/src/python/pyhbac.c:21:
  /usr/include/python3.6m/pyport.h:42:0: note: this is the location of the previous definition
   #define HAVE_LONG_LONG

We need to include config.h before Python.h to avoid redefinition of
HAVE_LONG_LONG which is definded conditionally in Python.h

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>

Moving the library to the lib directory will force maintainers to think
twice about changes, because it would be obvious this is a library.

Also don't use includes from sssd source tree paths, but add the util
path to Makefile's CFLAGS so that other projects can copy the
hbac_evaluator.c file verbatim.

Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>

Reviewed-by: Pavel Březina <pbrezina@redhat.com>

src/python/pyhbac.c: In function ‘HbacRuleElement_repr’:
src/python/pyhbac.c:506:59: error: comparison between
    signed and unsigned integer expressions [-Werror=sign-compare]
     if (strnames == NULL || strgroups == NULL || category == -1) {
                                                           ^
src/python/pyhbac.c: In function ‘HbacRuleElement_to_native’:
src/python/pyhbac.c:614:51: error: comparison between
    signed and unsigned integer expressions [-Werror=sign-compare]
     if (!el->names || !el->groups || el->category == -1) {
                                                   ^

The static function native_category had type of terurn value uint32_t
But it also could return -1 which indicated an error.

It's better to don't mix return code with returned value.

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

src/python/pysss_murmur.c: In function ‘py_murmurhash3’:
src/python/pysss_murmur.c:47:17: error: comparison between
     signed and unsigned integer expressions [-Werror=sign-compare]
         key_len > strlen(key)) {
                 ^

uint32_t murmurhash3(const char *key, int len, uint32_t seed)
The second argument of the function murmurhash3 has type int.
But the code expects to be unsigned integer.

There is code in python wrapper py_murmurhash3
which check boundaries of that argument.
It should be an unsigned "key_len > INT_MAX || key_len < 0".
An exception should be thrown for negative number.

Moreover, the length should be shorter then a length of input string.
The strlen returns size_t which is unsigned and key_len is signed long.
We already checked that value is unsigned so
we can safely cast key_len to size_t

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>

The function PyUnicode_FromString is available in python >= 2.6

Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>

The macro PySet_Check is defined in python >= 2.6

Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>

The function PySet_Add is available in python >= 2.6

Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>