Correctly detect the presence and location of all external library we use

(except for the C math library, which the C standard guarantees is always
available as -lm) and more importantly, use them only where needed.

This should fix the compilation issues on SuSE.


git-svn-id: http://www.varnish-cache.org/svn/trunk@1364 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/Makefile.am

@@ -61,4 +61,5 @@ varnishd_LDFLAGS = -export-dynamic
 varnishd_LDADD = \
 	$(top_builddir)/lib/libcompat/libcompat.a \
 	$(top_builddir)/lib/libvarnish/libvarnish.la \
-	$(top_builddir)/lib/libvcl/libvcl.la
+	$(top_builddir)/lib/libvcl/libvcl.la \
+	${DL_LIBS} ${RT_LIBS} ${PTHREAD_LIBS}

bin/varnishhist/Makefile.am

@@ -14,4 +14,5 @@ varnishhist_LDADD = \
 	$(top_builddir)/lib/libcompat/libcompat.a \
 	$(top_builddir)/lib/libvarnish/libvarnish.la \
 	$(top_builddir)/lib/libvarnishapi/libvarnishapi.la \
-	-lm -lcurses
+	-lm \
+	${CURSES_LIBS}

bin/varnishstat/Makefile.am

@@ -14,4 +14,4 @@ varnishstat_LDADD = \
 	$(top_builddir)/lib/libcompat/libcompat.a \
 	$(top_builddir)/lib/libvarnish/libvarnish.la \
 	$(top_builddir)/lib/libvarnishapi/libvarnishapi.la \
-	-lcurses
+	${CURSES_LIBS} ${RT_LIBS}

bin/varnishtop/Makefile.am

@@ -14,4 +14,4 @@ varnishtop_LDADD = \
 	$(top_builddir)/lib/libcompat/libcompat.a \
 	$(top_builddir)/lib/libvarnish/libvarnish.la \
 	$(top_builddir)/lib/libvarnishapi/libvarnishapi.la \
-	-lcurses
+	${CURSES_LIBS}

configure.ac

@@ -35,10 +35,33 @@ AC_PROG_LIBTOOL
 AC_PROG_MAKE_SET
 
 # Checks for libraries.
+save_LIBS="${LIBS}"
+LIBS=""
 AC_CHECK_LIB(rt, clock_gettime)
+RT_LIBS="${LIBS}"
+LIBS="${save_LIBS}"
+AC_SUBST(RT_LIBS)
+
+save_LIBS="${LIBS}"
+LIBS=""
 AC_CHECK_LIB(dl, dlopen)
-#AC_SEARCH_LIBS(initscr, [curses ncurses])
+DL_LIBS="${LIBS}"
+LIBS="${save_LIBS}"
+AC_SUBST(DL_LIBS)
+
+save_LIBS="${LIBS}"
+LIBS=""
+AC_SEARCH_LIBS(initscr, [curses ncurses])
+CURSES_LIBS="${LIBS}"
+LIBS="${save_LIBS}"
+AC_SUBST(CURSES_LIBS)
+
+save_LIBS="${LIBS}"
+LIBS=""
 AC_SEARCH_LIBS(pthread_create, [thr pthread c_r])
+PTHREAD_LIBS="${LIBS}"
+LIBS="${save_LIBS}"
+AC_SUBST(PTHREAD_LIBS)
 
 # Checks for header files.
 AC_HEADER_STDC
@@ -79,7 +102,11 @@ AC_CHECK_FUNCS([srandomdev])
 AC_CHECK_FUNCS([strlcat strlcpy])
 AC_CHECK_FUNCS([strndup])
 AC_CHECK_FUNCS([vis strvis strvisx])
+
+save_LIBS="${LIBS}"
+LIBS="${LIBS} ${RT_LIBS}"
 AC_CHECK_FUNCS([clock_gettime])
+LIBS="${save_LIBS}"
 
 # Check which mechanism to use for the acceptor
 AC_CHECK_FUNCS([kqueue])