+ DESIRED_FLAGS="-Wall -W -Wextra -pedantic -pipe -Wformat -Wold-style-definition -Wdeclaration-after-statement -Wfloat-equal -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wredundant-decls -Wmissing-noreturn -Wshadow -Wendif-labels -Wpointer-arith -Wbad-function-cast -Wcast-qual -Wcast-align -Wwrite-strings -fdiagnostics-show-option -Wno-cast-qual -fno-strict-aliasing"
+
+ for flag in $DESIRED_FLAGS ; do
+ AC_MSG_CHECKING([whether $CC accepts $flag])
+ if test_gcc_flag $flag ; then
+ CFLAGS="$CFLAGS $flag"
+ AC_MSG_RESULT([yes])
+ else
+ AC_MSG_RESULT([no])
+ fi
+ done
+fi
+
+# Checks for header files.
+AC_CHECK_HEADERS([arpa/inet.h fcntl.h netinet/in.h sys/ioctl.h sys/socket.h sys/time.h unistd.h])
+
+ # Solaris stuff
+ AC_SEARCH_LIBS([inet_ntop],[nsl])
+ AC_SEARCH_LIBS([recv],[socket])
+ AC_CHECK_DECL([CMSG_SPACE],,CFLAGS="$CFLAGS -D_XOPEN_SOURCE=500 -D__EXTENSIONS__", [[#include <sys/socket.h>]])
+
+# Checks for library functions.
+AC_FUNC_SELECT_ARGTYPES
+AC_CHECK_FUNCS([gethostname select socket uname strcasecmp gettimeofday strncasecmp strlcpy])
+
+AC_FUNC_CHOWN
+AC_FUNC_STAT
+AC_TYPE_MODE_T
+AC_TYPE_PID_T
+
+AC_CHECK_DECLS(environ)
+
+# check if gcc's -fvisibility is supported
+CHECK_VISIBILITY_HIDDEN
+
+# Check for pkg-config manually first, as if its not installed the
+# PKG_PROG_PKG_CONFIG macro won't be defined.
+AC_CHECK_PROG(have_pkg_config, pkg-config, yes, no)
+
+if test x"$have_pkg_config" = "xno"; then
+ AC_MSG_ERROR(pkg-config is required to install this program)