script: use lib/pty-session

This patch consolidate pseudo-terminal stuff in util-linux. From now
there is only one implementation used in su(1) --pty, scriptlive(1)
and script(1).

The new stuff is based on the original script(1) -- it means poll()
and signalfd() based.

Note that script(1) code does not provide fallback for systems/libc
where is no openpty().

Signed-off-by: Karel Zak <kzak@redhat.com>

configure.ac

@@ -1822,7 +1822,7 @@ UL_REQUIRES_LINUX([setarch])
 AM_CONDITIONAL([BUILD_SETARCH], [test "x$build_setarch" = xyes])
 
 UL_BUILD_INIT([script], [check])
-UL_REQUIRES_HAVE([script], [sys_signalfd_h], [sys/signalfd.h header])
+UL_REQUIRES_HAVE([script], [pty])
 AM_CONDITIONAL([BUILD_SCRIPT], [test "x$build_script" = xyes])
 
 UL_BUILD_INIT([scriptreplay], [yes])

term-utils/Makemodule.am

@@ -1,12 +1,12 @@
 if BUILD_SCRIPT
 usrbin_exec_PROGRAMS += script
 dist_man_MANS += term-utils/script.1
-script_SOURCES = term-utils/script.c lib/monotonic.c
+script_SOURCES = term-utils/script.c \
+		 lib/pty-session.c \
+		 include/pty-session.h \
+		 lib/monotonic.c
 script_CFLAGS = $(AM_CFLAGS) -Wno-format-y2k
-script_LDADD = $(LDADD) libcommon.la $(REALTIME_LIBS)
-if HAVE_UTIL
-script_LDADD += -lutil
-endif
+script_LDADD = $(LDADD) libcommon.la $(MATH_LIBS) $(REALTIME_LIBS) -lutil
 if HAVE_UTEMPTER
 script_LDADD += -lutempter
 endif