source: vendor/current/lib/resolv_wrapper/wscript

#!/usr/bin/env python

import os

VERSION="1.1.3"

def configure(conf):
    if conf.CHECK_BUNDLED_SYSTEM('resolv_wrapper', minversion=VERSION, set_target=False):
        conf.DEFINE('USING_SYSTEM_RESOLV_WRAPPER', 1)
        libresolv_wrapper_so_path = 'libresolv_wrapper.so'
    else:
        # check HAVE_GCC_THREAD_LOCAL_STORAGE
        conf.CHECK_CODE('''
            __thread int tls;

            int main(void) {
                return 0;
            }
            ''',
            'HAVE_GCC_THREAD_LOCAL_STORAGE',
            addmain=False,
            msg='Checking for thread local storage')

        # check HAVE_DESTRUCTOR_ATTRIBUTE
        conf.CHECK_CODE('''
            void test_destructor_attribute(void) __attribute__ ((destructor));

            void test_destructor_attribute(void)
            {
                return;
            }

            int main(void) {
                return 0;
            }
            ''',
            'HAVE_DESTRUCTOR_ATTRIBUTE',
            addmain=False,
            msg='Checking for library destructor support')

        # check HAVE_FUNCTION_ATTRIBUTE_FORMAT
        conf.CHECK_CODE('''
            void log_fn(const char *format, ...) __attribute__ ((format (printf, 1, 2)));

            int main(void) {
                return 0;
            }
            ''',
            'HAVE_FUNCTION_ATTRIBUTE_FORMAT',
            addmain=False,
            msg='Checking for printf format validation support')

        conf.CHECK_HEADERS('resolv.h')

        conf.CHECK_STRUCTURE_MEMBER('struct _res_state',
                                    '_u._ext.nsaddrs',
                                    headers='resolv.h',
                                    define='HAVE_RESOLV_IPV6_NSADDRS')

        conf.CHECK_FUNCS_IN('res_ninit', 'resolv')
        if conf.CONFIG_SET('HAVE_RES_NINIT'):
            conf.DEFINE('HAVE_RES_NINIT_IN_LIBRESOLV', 1)

        conf.CHECK_FUNCS_IN('res_nclose', 'resolv')
        if conf.CONFIG_SET('HAVE_RES_NCLOSE'):
            conf.DEFINE('HAVE_RES_NCLOSE_IN_LIBRESOLV', 1)

        conf.CHECK_FUNCS_IN('res_init __res_init', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_ninit __res_ninit', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_close __res_close', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_nclose __res_nclose', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_query __res_query', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_nquery __res_nquery', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_search __res_search', 'resolv', checklibc=True)
        conf.CHECK_FUNCS_IN('res_nsearch __res_nsearch', 'resolv', checklibc=True)

        conf.CHECK_DECLS('ns_name_compress', headers='sys/types.h arpa/nameser.h')
        if (conf.CONFIG_SET("HAVE_DECL_NS_NAME_COMPRESS")):
            conf.DEFINE("HAVE_NS_NAME_COMPRESS", 1)

        # Create full path to resolv_wrapper
        srcdir = os.path.realpath(conf.srcdir)
        libresolv_wrapper_so_path = srcdir + '/bin/default/lib/resolv_wrapper/libresolv-wrapper.so'

    conf.DEFINE('LIBRESOLV_WRAPPER_SO_PATH', libresolv_wrapper_so_path)
    conf.DEFINE('RESOLV_WRAPPER', 1)

def build(bld):
    if bld.CONFIG_SET("HAVE_RESOLV_H") and not bld.CONFIG_SET("USING_SYSTEM_RESOLV_WRAPPER"):
        # We need to do it this way or the library wont work.
        # Using private_library=True will add symbol version which
        # breaks preloading!
        bld.SAMBA_LIBRARY('resolv_wrapper',
                          source='resolv_wrapper.c',
                          deps='dl resolv',
                          install=False,
                          realname='libresolv-wrapper.so')