[Iftop-users] Supporting cross-compilation

-- Tim Freeman http://www.fungible.com tim@fungible.com Programmer/consultant in the Sunnyvale, CA area. diff -ru orig/iftop-0.16/configure.in ./configure.in --- orig/iftop-0.16/configure.in 2004-02-28 10:53:37.000000000 -0800 +++ ./configure.in 2005-06-11 11:02:04.000000000 -0700 @@ -9,7 +9,15 @@ dnl dnl $Id: configure.in,v 1.23 2004/02/28 18:53:37 pdw Exp $ dnl - +dnl To regenerate everything from source, do: +dnl autoheader +dnl aclocal +dnl automake +dnl autoconf +dnl Now you should have good sources to make into a tarball and distribute. +dnl ./configure (perhaps with some arguments) +dnl make +dnl Tested with Automake 1.4 and autoconf 2.59. dnl dnl Boilerplate configuration dnl @@ -34,15 +42,23 @@ dnl AC_ARG_WITH(resolver, - [ --with-resolver=TYPE Technique iftop should use for name resolution. Valid - options are netdb, netdb_1thread (for systems without - working gethostbyaddr_r), ares for the MIT ARES - asynchronous resolver library, forking for the REALLY - SUCKY forking resolver, or none if you don't need any - name resolution. - [default=netdb]], + [ --with-resolver=TYPE Technique iftop should use for name resolution. + Valid options are: + netdb use gethostbyaddr_r in multiple + threads. + netdb_1thread use gethostbyaddr_r and + assume it is not reentrant. + ares use the MIT ARES asynchronous + resolver library. + forking use the REALLY SUCKY forking resolver. + guess run experiments to guess a + reasonable value. Only works if you + aren't cross-compiling. This + is the default. guess will + either select netdb or netdb_1thread. + none don't do name resolution.], [resolver=$withval], - [resolver=netdb]) + [resolver=guess]) AC_ARG_WITH(libpcap, [ --with-libpcap=WHERE Where the libpcap packet-capture library is found. @@ -151,7 +167,12 @@ dnl First, the default resolver, which uses getnameinfo or gethostbyaddr_r. If dnl not available, we fall back to gethostbyaddr. We could fall back to ARES, dnl but that's probably not available on typical machines. -if test x$resolver = xnetdb ; then + +dnl If we've been asked to guess, remember that fact in specified_resolver. +dnl From this point on, resolver is our preferred resolver given the +dnl experiments we've done so far, or "guess" if we have no idea. +specified_resolver=$resolver +if test x$specified_resolver = xguess ; then dnl Best possibility is getnameinfo. use_getnameinfo=0 AC_SEARCH_LIBS(getnameinfo, [nsl], [use_getnameinfo=1]) @@ -164,75 +185,101 @@ dnl Done. AC_DEFINE(USE_GETNAMEINFO, 1, [use getnameinfo for name resolution]) else - dnl Now see if we can use gethostbyaddr_r. - AC_SEARCH_LIBS(gethostbyaddr_r, [nsl], , [resolver=forking]) + dnl Best hope is netdb, which presently means gethostbyaddr_r. + resolver=netdb + fi +fi + +if test x$resolver = xnetdb ; then + dnl Can use gethostbyaddr_r? + AC_SEARCH_LIBS(gethostbyaddr_r, [nsl], , [resolver=guess]) + if test x$resolver = xguess && test x$specified_resolver != xguess ; then + dnl They wanted gethostbyaddr_r, but they can't have it, so stop. + AC_MSG_ERROR([no library defines gethostbyaddr_r]) + fi +fi + +dnl We still might do gethostbyaddr_r. Figure out whether we have +dnl glibc-style or Solaris-style gethostbyaddr_r (or neither...). +dnl Separate determining how to call gethostbyaddr_r from testing +dnl whether it works so we can support cross-compilation. +if test x$resolver = xnetdb ; then + AC_MSG_CHECKING([how to call gethostbyaddr_r]) + dnl Try 7 arguments returning a struct hostent*. + AC_LINK_IFELSE(AC_LANG_SOURCE([`cat config/hostentp_ghba_r.c`]), + [AC_MSG_RESULT([7 args]) + ghba_args=8 + AC_DEFINE(GETHOSTBYADDR_R_RETURNS_HOSTENT_P, 1, + [7-argument gethostbyaddr_r returns struct hostent*])], [ + dnl Try 8 arguments returning an int. + AC_LINK_IFELSE(AC_LANG_SOURCE([`cat config/int_ghba_r.c`]), + [AC_MSG_RESULT([8 args, int return]) + ghba_args=8 + AC_DEFINE(GETHOSTBYADDR_R_RETURNS_INT, 1, + [8-argument gethostbyaddr_r returns int])], [ + dnl Neither. + AC_MSG_RESULT([don't know how]) + resolver=guess])]) + if test x$resolver = xguess && test x$specified_resolver != xguess ; then + dnl They wanted gethostbyaddr_r, but they can't have it, so stop. + AC_MSG_ERROR([gethostbyaddr_r has no known calling convention]) + fi +fi - dnl Still want gethostbyaddr_r.... - if test x$resolver = xnetdb ; then - dnl Figure out whether we have glibc-style or Solaris-style - dnl gethostbyaddr_r (or neither...). - AC_MSG_CHECKING([how to call gethostbyaddr_r]); - - AC_TRY_RUN([`cat config/int_ghba_r.c`], [ - dnl 8-arg, int - AC_MSG_RESULT([8 args, int return]) - AC_DEFINE(GETHOSTBYADDR_R_RETURNS_INT, 1, - [8-argument gethostbyaddr_r returns int]) - ], [ - AC_TRY_RUN([`cat config/hostentp_ghba_r.c`], [ - dnl 7-arg, struct hostent* - AC_MSG_RESULT([7 args, struct hostent* return]) - AC_DEFINE(GETHOSTBYADDR_R_RETURNS_HOSTENT_P, 1, - [7-argument gethostbyaddr_r returns struct hostent*]) - ], [ - dnl neither - AC_MSG_RESULT([no idea; dropping back to the forking resolver]) - resolver=forking - ]) - ]) - - dnl Found a gethostbyaddr_r we know how to use and which seems to - dnl work. - if test x$resolver = xnetdb ; then - AC_DEFINE(USE_GETHOSTBYADDR_R, 1, [use gethostbyaddr_r for name resolution]) - fi +dnl If we still want to do gethostbyaddr_r, and we aren't +dnl cross-compiling, test it. +if test x$resolver = xnetdb ; then + if test x$ghba_args = x8 ; then + testfile=int_ghba_r + else + testfile=hostentp_ghba_r + fi + AC_MSG_CHECKING(gethostbyaddr_r usability) + AC_RUN_IFELSE([`cat config/$testfile.c`], + [AC_MSG_RESULT([yes])], + [AC_MSG_RESULT([no]) + resolver=guess], + [AC_MSG_RESULT([can't test because we are cross-compiling])]) + if test x$resolver = xguess ; then + if test x$specified_resolver = xguess ; then + AC_MSG_RESULT([gethostbyaddr_r doesn't work, so we'll try something else]) + else + dnl They wanted gethostbyaddr_r, but it doesn't work, so stop. + AC_MSG_ERROR([gethostbyaddr_r doesn't work]) fi fi fi -dnl If we've been told to use ARES, then see if it's available. If it isn't, -dnl fall back to gethostbyaddr, since we can probably assume that if the -dnl machine had a working gethostbyaddr_r, the user wouldn't be pissing about -dnl with ARES. +dnl We found a gethostbyaddr_r we know how to use and which seems to +dnl work. +if test x$resolver = xnetdb ; then + AC_DEFINE(USE_GETHOSTBYADDR_R, 1, [use gethostbyaddr_r for name resolution]) +fi + +dnl They may have asked for ares. if test x$resolver = xares ; then dnl See if ares is to hand.... AC_SEARCH_LIBS(ares_init, [ares], [ AC_DEFINE(USE_ARES, 1, [use ARES for name resolution]) ], [ - dnl no ares - AC_MSG_RESULT([can't find ARES; dropping back to the forking resolver]) - resolver=forking]) + dnl They asked for ares, but we can't give it to them, so stop. + AC_MSG_ERROR([can't find ARES. Re-run configure and ask for a different resolver.])]) fi +dnl Last thing to try if we haven't decided yet is netdb_1thread. +if test x$resolver = xguess ; then + resolver=netdb_1thread +fi dnl Ugh. Both the single-threaded and the forking resolvers use gethostbyaddr. if test x$resolver = xnetdb_1thread || test x$resolver = xforking ; then AC_SEARCH_LIBS(gethostbyaddr, [nsl], , [ - AC_MSG_ERROR([not even gethostbyaddr is available - What sort of UNIX system is this, anyway? - - You will have to recompile with no name resolution at all. -]) - - ] - ) + AC_MSG_ERROR([gethostbyaddr is not available. You will have to + recompile with no name resolution at all.])]) if test x$resolver = xnetdb_1thread ; then - dnl Oh dear, just use gethostbyaddr; but whine about it - AC_MSG_WARN([using single-threaded resolver with gethostbyaddr Consider obtaining ARES or a machine with a working gethostbyaddr_r.]) - AC_DEFINE(USE_GETHOSTBYADDR, 1, [use gethostbyaddr for name resolution]) else AC_DEFINE(USE_FORKING_RESOLVER, 1, [use a REALLY SUCKY forking resolver for name resolution]) @@ -332,7 +379,7 @@ dnl libraries, etc. We use a test program to figure this stuff out. dnl -AC_MSG_CHECKING([how to compile a working program with POSIX threads]) +AC_MSG_CHECKING([POSIX threads compilation]) thrfail=1 oldCFLAGS=$CFLAGS oldLIBS=$LIBS @@ -340,7 +387,7 @@ CFLAGS="$oldCFLAGS $flag" for lib in "" -lpthread "-lpthread -lposix4" ; do LIBS="$oldLIBS $lib" - AC_TRY_RUN([`cat config/pthread.c`], [ + AC_LINK_IFELSE(AC_LANG_SOURCE([`cat config/pthread.c`]), [ foundthrlib=$lib foundthrflag=$flag thrfail=0 @@ -356,10 +403,16 @@ AC_MSG_RESULT([no idea]) AC_MSG_ERROR([can't figure out how to compile with POSIX threads If your system actually supports POSIX threads, this means we've messed up.]) -else - AC_MSG_RESULT([$foundthrflag $foundthrlib]) fi +AC_MSG_RESULT([CFLAGS=$foundthrflag and LIBS=$foundthrlib]) +AC_MSG_CHECKING([POSIX threads usability]) +AC_RUN_IFELSE([`cat config/pthread.c`], + [AC_MSG_RESULT([yes])], + [AC_MSG_ERROR( + [it fails. We probably guessed the wrong CFLAGS.])], + [AC_MSG_RESULT([can't test because we are cross-compiling])]) + dnl dnl Are we on a system (like Solaris) that requires promiscuous mode in order to dnl see any outgoing packets? @@ -374,7 +427,8 @@ esac AC_ARG_ENABLE(default-promiscuous, - [--enable-default-promiscuous If enabled, iftop will operate in promiscuous mode to capture outgoing packets]) + [ --enable-default-promiscuous If enabled, iftop will operate in promiscuous mode + to capture outgoing packets]) AC_MSG_RESULT([$enable_default_promiscuous]) diff -ru orig/iftop-0.16/ui.c ./ui.c --- orig/iftop-0.16/ui.c 2004-02-05 14:53:19.000000000 -0800 +++ ./ui.c 2005-06-04 11:03:06.000000000 -0700 @@ -1045,6 +1045,7 @@ break; } case '!': { +#ifndef NO_SYSTEM char *s; dontshowdisplay = 1; if ((s = edline(0, "Command", "")) && s[strspn(s, " \t")]) { @@ -1073,6 +1074,9 @@ xfree(s); } dontshowdisplay = 0; +#else + showhelp("Sorry, subshells have been disabled."); +#endif break; } case 'T':