Avoid libdl dependencies in bundled libverto

The upstream libverto depends on dynamic loading and in particular on
dladdr(), which is not universal.  To avoid this dependency, stub out
support for module loading (by replacing module.c) and instead
integrate the k5ev module directly into the bundled verto library.

This change removes the need to link, include, and invoke libverto
differently depending on whether we're using the bundled library; we
can always just link with -lverto and call verto_default().

bigredbutton: whitespace
ticket: 7351 (new)

src/config/pre.in

@@ -369,9 +369,6 @@ VERTO_VERSION	= @VERTO_VERSION@
 VERTO_DEPS	= $(VERTO_DEPS-@VERTO_VERSION@)
 VERTO_DEPS-sys	=
 VERTO_DEPS-k5	= $(BUILDTOP)/include/verto.h
-VERTO_K5EV_DEPS	= $(VERTO_K5EV_DEPS-@VERTO_VERSION@)
-VERTO_K5EV_DEPS-sys =
-VERTO_K5EV_DEPS-k5 = $(BUILDTOP)/include/verto-k5ev.h
 
 # LIBS gets substituted in... e.g. -lnsl -lsocket
 
@@ -389,7 +386,7 @@ KDB5_LIB	= -lkdb5 $(KDB5_PLUGIN_LIBS)
 
 VERTO_DEPLIB	= $(VERTO_DEPLIB-@VERTO_VERSION@)
 VERTO_DEPLIB-sys = # empty
-VERTO_DEPLIB-k5	= $(TOPLIBD)/libverto-k5ev$(DEPLIBEXT) $(TOPLIBD)/libverto$(DEPLIBEXT)
+VERTO_DEPLIB-k5	= $(TOPLIBD)/libverto$(DEPLIBEXT)
 VERTO_CFLAGS	= @VERTO_CFLAGS@
 VERTO_LIBS	= @VERTO_LIBS@
 

src/configure.in

@@ -1219,15 +1219,15 @@ AC_ARG_WITH([system-verto],
   [AC_HELP_STRING([--with-system-verto], [always use system verto library])],
   [], [with_system_verto=default])
 VERTO_CFLAGS=
-VERTO_LIBS="-lverto-k5ev -lverto"
+VERTO_LIBS="-lverto"
 VERTO_VERSION=k5
 if test "x$with_system_verto" != xno; then
   if verto_cflags=`pkg-config --cflags libverto 2>&1`; then
     VERTO_CFLAGS=$verto_cflags
     VERTO_LIBS=`pkg-config --libs libverto`
     VERTO_VERSION=sys
   else
-    AC_CHECK_LIB([verto], [verto_run], [VERTO_VERSION=sys; VERTO_LIBS=-lverto],
+    AC_CHECK_LIB([verto], [verto_run], [VERTO_VERSION=sys],
       [if test "x$with_system_verto" = xyes; then
         AC_MSG_ERROR([cannot detect system libverto])
       fi])
@@ -1237,7 +1237,6 @@ if test "x$VERTO_VERSION" = xsys; then
   AC_MSG_NOTICE([Using system libverto])
 else
   AC_MSG_RESULT([Using built-in libverto])
-  AC_DEFINE([INTERNAL_VERTO],[1],[Define if using bundled libverto])
 fi
 AC_SUBST([VERTO_CFLAGS])
 AC_SUBST([VERTO_LIBS])
@@ -1295,7 +1294,7 @@ AC_CONFIG_FILES(krb5-config, [chmod +x krb5-config])
 V5_AC_OUTPUT_MAKEFILE(.
 
 	util util/support util/profile util/profile/testmod util/send-pr
-	util/verto util/k5ev
+	util/verto
 
 	lib lib/kdb
 

src/lib/apputils/deps

@@ -16,7 +16,7 @@ net-server.so net-server.po $(OUTPRE)net-server.$(OBJEXT): \
   $(BUILDTOP)/include/autoconf.h $(BUILDTOP)/include/gssapi/gssapi.h \
   $(BUILDTOP)/include/gssrpc/types.h $(BUILDTOP)/include/krb5/krb5.h \
   $(BUILDTOP)/include/osconf.h $(BUILDTOP)/include/profile.h \
-  $(COM_ERR_DEPS) $(VERTO_DEPS) $(VERTO_K5EV_DEPS) $(top_srcdir)/include/adm_proto.h \
+  $(COM_ERR_DEPS) $(VERTO_DEPS) $(top_srcdir)/include/adm_proto.h \
   $(top_srcdir)/include/fake-addrinfo.h $(top_srcdir)/include/foreachaddr.h \
   $(top_srcdir)/include/gssrpc/auth.h $(top_srcdir)/include/gssrpc/auth_gss.h \
   $(top_srcdir)/include/gssrpc/auth_unix.h $(top_srcdir)/include/gssrpc/clnt.h \

src/lib/apputils/net-server.c

@@ -58,10 +58,6 @@
 
 #include "fake-addrinfo.h"
 #include "net-server.h"
-#ifdef INTERNAL_VERTO
-#include "verto-k5ev.h"
-#endif
-
 #include <signal.h>
 
 /* XXX */
@@ -269,12 +265,7 @@ loop_init(verto_ev_type types)
     types |= VERTO_EV_TYPE_IO;
     types |= VERTO_EV_TYPE_SIGNAL;
     types |= VERTO_EV_TYPE_TIMEOUT;
-
-#ifdef INTERNAL_VERTO
-    return verto_default_k5ev();
-#else
     return verto_default(NULL, types);
-#endif
 }
 
 static void

src/util/Makefile.in

@@ -15,7 +15,7 @@ MAYBE_ET_sys =
 MAYBE_ET_intlsys =
 MAYBE_SS_sys =
 MAYBE_VERTO_sys =
-MAYBE_VERTO_k5 = verto k5ev
+MAYBE_VERTO_k5 = verto
 
 all-recurse:
 

src/util/depfix.pl

@@ -141,7 +141,6 @@ sub do_subs_2 {
     s;\$\(BUILDTOP\)/include/com_err.h ;\$(COM_ERR_DEPS) ;g;
     s;\$\(BUILDTOP\)/include/ss/ss.h \$\(BUILDTOP\)/include/ss/ss_err.h ;\$(SS_DEPS) ;g;
     s;\$\(BUILDTOP\)/include/db-config.h \$\(BUILDTOP\)/include/db.h ;\$(DB_DEPS) ;g;
-    s;\$\(BUILDTOP\)/include/verto-k5ev.h ;\$(VERTO_K5EV_DEPS) ;g;
     s;\$\(BUILDTOP\)/include/verto.h ;\$(VERTO_DEPS) ;g;
     if ($thisdir eq "util/gss-kernel-lib") {
 	# Here com_err.h is used from the current directory.

src/util/verto/Makefile.in

@@ -6,32 +6,38 @@ LIBBASE=verto
 LIBMAJOR=0
 LIBMINOR=0
 
-LOCALINCLUDES=-I$(srcdir)
-DEFINES=-DDEFAULT_LIBRARY=\"k5ev\"
+LOCALINCLUDES=-I$(srcdir) -I.
+DEFINES=-DDEFAULT_LIBRARY=\"k5ev\" -DBUILTIN_MODULE=k5ev
 
 # Turn off extra warnings since we're not going to clean up libverto's code.
 WARN_CFLAGS=
 
-STLIBOBJS=verto.o module.o
-LIBOBJS=$(OUTPRE)verto.$(OBJEXT) $(OUTPRE)module.$(OBJEXT)
-SRCS=verto.c module.c
+STLIBOBJS=verto.o module.o verto-k5ev.o
+LIBOBJS=$(OUTPRE)verto.$(OBJEXT) \
+	$(OUTPRE)module.$(OBJEXT) \
+	$(OUTPRE)verto-k5ev.$(OBJEXT)
+SRCS=verto.c module.c verto-k5ev.c
 
 STOBJLISTS=OBJS.ST
-SHLIB_EXPLIBS= $(DL_LIB) $(LIBS)
+SHLIB_EXPLIBS= $(LIBS) -lm    # libm needed for ceil() currently.
 SHLIB_DIRS=
 SHLIB_RDIRS=$(KRB5_LIBDIR)
 
 VERTO_HDR=$(BUILDTOP)$(S)include$(S)verto.h
 
+rename.h: $(srcdir)/Symbols.ev
+	$(RM) $@
+	$(SED) -e 's/.*/#define & k5&/' < $(srcdir)/Symbols.ev > $@
+
 all-unix:: all-liblinks includes
 
 install-unix:: install-libs
 
 clean-unix:: clean-liblinks clean-libs clean-libobjs
-	$(RM) $(VERTO_HDR)
+	$(RM) $(VERTO_HDR) rename.h
 
 includes:: $(VERTO_HDR)
-depend:: $(VERTO_HDR)
+depend:: $(VERTO_HDR) rename.h
 
 $(VERTO_HDR): $(srcdir)/verto.h
 	$(RM) $@

src/util/verto/README

@@ -1,6 +1,40 @@
-This directory builds a verto library with only a private back-end
-module, for use when the system has no installed verto library.
+This directory builds a verto library with only a private built-in
+module, for use when the system has no installed verto library.  The
+bundled verto cannot dynamically load modules.  From the upstream
+libverto, we take only verto.c and verto-libev.c, and we only build
+the former; the latter is stored here for comparison purposes.  We use
+a stub implementation of module.c to disable dynamic loading support.
 
-The libverto upstream project page is at:
+This private module uses an embedded libev with renamed symbols (so we
+don't leak libev symbols into the namespace on platforms where we
+can't control the export list).  libev has built-in support for this
+kind of embedding, so we don't have to modify the libev sources.
+Following libev's documentation, the following files have been copied
+from the ev sources:
+
+  ev.h
+  ev_vars.h
+  ev_wrap.h
+  ev.c
+  ev_select.c
+  ev_poll.c
+  ev_win32.c
+  Symbols.ev
+
+(Symbols.ev wasn't included in the 4.04 tar file due to an oversight,
+so it is taken from the appropriate tag in libev's source repository.)
+
+To rename the exported symbols, we create rename.h from Symbols.ev.
+We also use Symbols.ev to construct the library export list.
+(Renaming libev's symbols would be unnecessary if libev's embedding
+had support for making its API symbols static, but it currently does
+not.)  The source file verto-k5ev.c wraps ev.c with appropriate
+embedding defines, and then defines the libverto module functions
+using the slightly modified contents of libverto's verto-libev.c.  The
+resulting module table is embedded into verto.c using the
+BUILTIN_MODULE define.
+
+The libverto and libev upstream project pages are at:
 
   https://fedorahosted.org/libverto/
+  http://software.schmorp.de/pkg/libev.html

src/util/verto/deps

@@ -4,3 +4,7 @@
 verto.so verto.po $(OUTPRE)verto.$(OBJEXT): $(VERTO_DEPS) \
   module.h verto-module.h verto.c
 module.so module.po $(OUTPRE)module.$(OBJEXT): module.c
+verto-k5ev.so verto-k5ev.po $(OUTPRE)verto-k5ev.$(OBJEXT): \
+  $(BUILDTOP)/include/autoconf.h $(VERTO_DEPS) ev.c ev.h \
+  ev_poll.c ev_select.c ev_vars.h ev_wrap.h rename.h \
+  verto-k5ev.c verto-module.h