From: "Daniel P. Berrange" <berrange@xxxxxxxxxx> Most checks for libraries take the same format * --with-libFOO=yes|no|check|/some/path argument * check for a function NNN in libFOO.so * check for a header file DDD/HHH.h * Define a WITH_FOO config.h symbol * Define a WITH_FOO make conditional * Substitute FOO_CFLAGS and FOO_LIBS make variables * Print CFLAGS & LIBS summary at the end Doing all this correctly is rather difficult, typically done by copy+paste of a previous usage. Further small improvements people make are not applied to all previous usages. Improve this by creating some helper macros to apply good practice. First, to perform the actual checks: LIBVIRT_CHECK_LIB([SELINUX],[selinux],[getfilecon][selinux/selinux.h]) This checks for 'getfilecon' in libselinux.so, and the existance of 'selinux/selinux.h' header file. If successful it sets SELINUX_CFLAGS and SELINUX_LIBS. The WITH_SELINUX config.h macro and WITH_SELINUX make conditional are also defined. Finally to print a summary of CFLAGS & LIBs found (if any): LIBVIRT_RESULT_LIB([SELINUX],[selinux]) Signed-off-by: Daniel P. Berrange <berrange@xxxxxxxxxx> --- m4/virt-lib.m4 | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ m4/virt-result.m4 | 9 ++++++ 2 files changed, 91 insertions(+) create mode 100644 m4/virt-lib.m4 create mode 100644 m4/virt-result.m4 diff --git a/m4/virt-lib.m4 b/m4/virt-lib.m4 new file mode 100644 index 0000000..9cdaf7f --- /dev/null +++ b/m4/virt-lib.m4 @@ -0,0 +1,82 @@ +dnl +dnl Probe for existance of libattr and set WITH_LIBATTR +dnl config header var, WITH_LIBATTR make conditional and +dnl with_libattr configure shell var. +dnl +dnl LIBVIRT_CHECK_LIB([VARNAME],[LIBNAME],[FUNCNAME],[HDRNAME]) +dnl +dnl eg +dnl +dnl LIBVIRT_CHECK_LIB([SELINUX],[selinux],[getfilecon][selinux/selinux.h]) +dnl +dnl LIBVIRT_RESULT_LIB([SELINUX],[selinux]) +dnl +AC_DEFUN([LIBVIRT_CHECK_LIB],[ + AS_VAR_PUSHDEF([with_var],[with_lib$2]) + AS_VAR_PUSHDEF([cflags_var],[$1_CFLAGS]) + AS_VAR_PUSHDEF([libs_var],[$1_LIBS]) + + AC_ARG_WITH([lib$2], + AC_HELP_STRING([--with-lib$2], + [with lib$2 support @<:@default=check@:>@]),[],[with_var][=check]) + + old_LIBS="$LIBS" + old_CFLAGS="$CFLAGS" + AS_VAR_SET([cflags_var],[]) + AS_VAR_SET([libs_var],[]) + + fail=0 + if test "$with_var" != "no" ; then + if test "$with_var" != "yes" && test "$with_var" != "check" ; then + AS_VAR_SET([cflags_var],[-I$with_var/include]) + AS_VAR_SET([libs_var],[-L$with_var/lib]) + fi + CFLAGS="$CFLAGS $cflags_var" + LIBS="$LIBS $libs_var" + AC_CHECK_LIB([$2], [$3], [ + AC_CHECK_HEADER([$4], [ + AS_VAR_SET([with_var],[yes]) + ],[ + if test "$with_var" != "check"; then + fail=1 + fi + AS_VAR_SET([with_var],[no]) + ]) + ],[ + if test "$with_var" != "check"; then + fail=1 + fi + AS_VAR_SET([with_var],[no]) + ]) + fi + + LIBS="$old_LIBS" + CFLAGS="$old_CFLAGS" + + if test $fail = 1; then + AC_MSG_ERROR([You must install the lib$2 library & headers to compile libvirt]) + fi + + if test "$with_var" = "yes" ; then + if test -z "$libs_var" ; then + AS_VAR_SET([libs_var],["-l$2"]) + else + AS_VAR_SET([libs_var],["$][libs_var][ -l$2"]) + fi + + AC_DEFINE_UNQUOTED([WITH_$1], 1, [whether lib$2 is available]) + fi + + AM_CONDITIONAL([WITH_$1], [test "$with_var" = "yes"]) + + AC_SUBST(cflags_var) + AC_SUBST(libs_var) +]) + +AC_DEFUN([LIBVIRT_RESULT_LIB],[ + AS_VAR_PUSHDEF([with_var],[with_lib$2]) + AS_VAR_PUSHDEF([cflags_var],[$1_CFLAGS]) + AS_VAR_PUSHDEF([libs_var],[$1_LIBS]) + + LIBVIRT_RESULT([$2], [$with_var], [CFLAGS=$cflags_var LIBS=$libs_var]) +]) diff --git a/m4/virt-result.m4 b/m4/virt-result.m4 new file mode 100644 index 0000000..85ae98f --- /dev/null +++ b/m4/virt-result.m4 @@ -0,0 +1,9 @@ +AC_DEFUN([LIBVIRT_RESULT], [ + if test "$2" = "no" || test -z "$3" ; then + printf -v STR "%8s: %4s" "$1" "$2" + else + printf -v STR "%8s: %4s (%s)" "$1" "$2" "$3" + fi + + AC_MSG_NOTICE([$STR]) +]) -- 1.7.11.4 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list