[PATCH] Allow to disable components

[Akihiko Odaki <akihiko dot odaki dot 4i at stu dot hosei dot ac dot jp>]

Signed-off-by: Akihiko Odaki <akihiko.odaki.4i@stu.hosei.ac.jp>
---
 Makefile.am  |  27 +++++++++++++--
 configure.ac | 107 ++++++++++++++++++++++++++++++++++++++++++-----------------
 lib/system.h |   9 ++++-
 3 files changed, 110 insertions(+), 33 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index 2ff444e..7abd95f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -27,8 +27,31 @@ AM_MAKEFLAGS = --no-print-directory
 pkginclude_HEADERS = version.h
 
 # Add doc back when we have some real content.
-SUBDIRS = config m4 lib libelf libebl libdwelf libdwfl libdw libcpu libasm \
-	  backends src po tests
+SUBDIRS = config m4 libelf po tests
+
+if ENABLE_LIBEU
+SUBDIRS += lib
+endif
+
+if ENABLE_LIBEBL
+SUBDIRS += libebl
+endif
+
+if ENABLE_LIBDW
+SUBDIRS += libdwelf libdwfl libdw
+endif
+
+if ENABLE_LIBEBL
+SUBDIRS += libcpu backends
+endif
+
+if ENABLE_LIBASM
+SUBDIRS += libasm
+endif
+
+if ENABLE_TOOLS
+SUBDIRS += src
+endif
 
 EXTRA_DIST = elfutils.spec GPG-KEY NOTES CONTRIBUTING \
 	     COPYING COPYING-GPLV2 COPYING-LGPLV3
diff --git a/configure.ac b/configure.ac
index e5503f1..cf6a59c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -214,6 +214,28 @@ AS_HELP_STRING([--enable-tests-rpath],[build $ORIGIN-using rpath into tests]),
 	       [tests_use_rpath=$enableval], [tests_use_rpath=no])
 AM_CONDITIONAL(TESTS_RPATH, test "$tests_use_rpath" = yes)
 
+AC_ARG_ENABLE([tools],
+AS_HELP_STRING([--disable-tools], [do not build tools]),
+	       [tools=$enableval], [tools=yes])
+AM_CONDITIONAL(ENABLE_TOOLS, test "$tools" = yes)
+
+AC_ARG_ENABLE([libasm],
+AS_HELP_STRING([--disable-libasm], [do not build libasm]),
+	       [libasm=$enableval], [libasm=yes])
+AM_CONDITIONAL(ENABLE_LIBASM, test "$libasm" = yes)
+
+AC_ARG_ENABLE([libdw],
+AS_HELP_STRING([--disable-libdw], [do not build libdw]),
+	       [libdw=$enableval], [libdw=yes])
+AM_CONDITIONAL(ENABLE_LIBDW, test "$libdw" = yes)
+
+AC_ARG_ENABLE([libebl],
+AS_HELP_STRING([--disable-libebl], [do not build libebl]),
+	       [libebl=$enableval], [libebl=yes])
+AM_CONDITIONAL(ENABLE_LIBEBL, test "$libebl" = yes)
+
+AM_CONDITIONAL(ENABLE_LIBEU, test "$libdw" = yes -o "$libebl" = yes)
+
 LIBEBL_SUBDIR="$PACKAGE"
 AC_ARG_ENABLE([libebl-subdir],
 AS_HELP_STRING([--enable-libebl-subdir=DIR],
@@ -306,30 +328,32 @@ CFLAGS="$old_CFLAGS"])
 AM_CONDITIONAL(HAVE_NULL_DEREFERENCE_WARNING,
 	       [test "x$ac_cv_null_dereference" != "xno"])
 
-dnl Check if we have argp available from our libc
-AC_LINK_IFELSE(
-	[AC_LANG_PROGRAM(
-		[#include <argp.h>],
-		[int argc=1; char *argv[]={"test"}; argp_parse(0,argc,&argv,0,0,0); return 0;]
-		)],
-	[libc_has_argp="true"],
-	[libc_has_argp="false"]
-)
-
-dnl If our libc doesn't provide argp, then test for libargp
-if test "$libc_has_argp" = "false" ; then
-	AC_MSG_WARN("libc does not have argp")
-	AC_CHECK_LIB([argp], [argp_parse], [have_argp="true"], [have_argp="false"])
-
-	if test "$have_argp" = "false"; then
-		AC_MSG_ERROR("no libargp found")
+if test "$tools" = yes ; then
+	dnl Check if we have argp available from our libc
+	AC_LINK_IFELSE(
+		[AC_LANG_PROGRAM(
+			[#include <argp.h>],
+			[int argc=1; char *argv[]={"test"}; argp_parse(0,argc,&argv,0,0,0); return 0;]
+			)],
+		[libc_has_argp="true"],
+		[libc_has_argp="false"]
+	)
+
+	dnl If our libc doesn't provide argp, then test for libargp
+	if test "$libc_has_argp" = "false" ; then
+		AC_MSG_WARN("libc does not have argp")
+		AC_CHECK_LIB([argp], [argp_parse], [have_argp="true"], [have_argp="false"])
+
+		if test "$have_argp" = "false"; then
+			AC_MSG_ERROR("no libargp found")
+		else
+			argp_LDADD="-largp"
+		fi
 	else
-		argp_LDADD="-largp"
+		argp_LDADD=""
 	fi
-else
-	argp_LDADD=""
+	AC_SUBST([argp_LDADD])
 fi
-AC_SUBST([argp_LDADD])
 
 dnl Check if we have <linux/bpf.h> for EM_BPF disassembly.
 AC_CHECK_HEADERS(linux/bpf.h)
@@ -348,29 +372,47 @@ dnl ELF library.
 AC_CONFIG_FILES([libelf/Makefile])
 
 dnl Higher-level ELF support library.
-AC_CONFIG_FILES([libebl/Makefile])
+if test "$libebl" = yes ; then
+	AC_CONFIG_FILES([libebl/Makefile])
+fi
 
 dnl DWARF-ELF Lower-level Functions support library.
-AC_CONFIG_FILES([libdwelf/Makefile])
+if test "$libdw" = yes; then
+	AC_CONFIG_FILES([libdwelf/Makefile])
+fi
 
 dnl DWARF library.
-AC_CONFIG_FILES([libdw/Makefile])
+if test "$libdw" = yes; then
+	AC_CONFIG_FILES([libdw/Makefile])
+fi
 
 dnl Higher-level DWARF support library.
-AC_CONFIG_FILES([libdwfl/Makefile])
+if test "$libdw" = yes; then
+	AC_CONFIG_FILES([libdwfl/Makefile])
+fi
 
 dnl CPU handling library.
-AC_CONFIG_FILES([libcpu/Makefile])
+if test "$libebl" = yes; then
+	AC_CONFIG_FILES([libcpu/Makefile])
+fi
 
 dnl Assembler library.
-AM_CONDITIONAL(HAVE_LIBASM, true)dnl Used in tests/Makefile.am, which see.
-AC_CONFIG_FILES([libasm/Makefile])
+AM_CONDITIONAL(HAVE_LIBASM, test "$libasm" = yes)dnl Used in tests/Makefile.am, which see.
+if test "$libasm" = yes; then
+	AC_CONFIG_FILES([libasm/Makefile])
+fi
 
 dnl CPU-specific backend libraries.
-AC_CONFIG_FILES([backends/Makefile])
+if test "$libebl" = yes; then
+	AC_CONFIG_FILES([backends/Makefile])
+fi
 
 dnl Tools.
-AC_CONFIG_FILES([src/Makefile po/Makefile.in])
+if test "$tools" = yes ; then
+	AC_CONFIG_FILES([src/Makefile])
+fi
+
+AC_CONFIG_FILES([po/Makefile.in])
 
 dnl Test suite.
 AM_CONDITIONAL(STANDALONE, false)dnl Used in tests/Makefile.am, which see.
@@ -384,6 +426,11 @@ AC_CONFIG_FILES([config/libelf.pc config/libdw.pc])
 AC_SUBST(USE_NLS, yes)
 AM_PO_SUBDIRS
 
+AH_TEMPLATE([ENABLE_TOOLS], [Defined if the tools will be built.])
+if test "$tools" = yes ; then
+	AC_DEFINE([ENABLE_TOOLS])
+fi
+
 dnl Appended to the config.h file.
 dnl We hide all kinds of configuration magic in lib/eu-config.h.
 AH_BOTTOM([#include <eu-config.h>])
diff --git a/lib/system.h b/lib/system.h
index f31cfd0..6391dec 100644
--- a/lib/system.h
+++ b/lib/system.h
@@ -29,7 +29,12 @@
 #ifndef LIB_SYSTEM_H
 #define LIB_SYSTEM_H	1
 
-#include <argp.h>
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#ifdef ENABLE_TOOLS
+# include <argp.h>
+#endif
 #include <stddef.h>
 #include <stdint.h>
 #include <endian.h>
@@ -126,6 +131,7 @@ pread_retry (int fd, void *buf, size_t len, off_t off)
 }
 
 
+#ifdef ENABLE_TOOLS
 /* We need define two variables, argp_program_version_hook and
    argp_program_bug_address, in all programs.  argp.h declares these
    variables as non-const (which is correct in general).  But we can
@@ -136,6 +142,7 @@ pread_retry (int fd, void *buf, size_t len, off_t off)
    __asm ("argp_program_version_hook")
 #define ARGP_PROGRAM_BUG_ADDRESS_DEF \
   const char *const apba__ __asm ("argp_program_bug_address")
+#endif
 
 
 /* The demangler from libstdc++.  */
-- 
2.10.0