Find fts-standalone on musl

When using the musl C library fts is optional.  So we need to detect
its presence by looking at the fts-standalone pkgconfig module.

This patch does that.

This comes from Gentoo bug https://bugs.gentoo.org/831571

	* configure.ac: Invoke AC_CANONICAL_HOST to compute the host_cpu,
	host_vendor, host_os parts of the 'host" variable.  Then if the
	host_os ends up with "musl" then, check for the fts-standalone
	pkgconfig module and record the fts library into
	FTS_{LIBS,CFLAGS}.
	* src/Makefile.am: Link to $FTS_LIBS and use $FTS_CFLAGS for
	compilation.
	* tools/Makefile.am: Likewise.
	* tools/abisym.cc: Include libgen.h
	* tools/kmidiff.cc: Remove useless fts.h header file.

Signed-off-by: David Seifert <soap@gentoo.org>
Signed-off-by: Dodji Seketeli <dodji@redhat.com>

4 files changed, 11 insertions, 4 deletions

diff --git a/configure.ac b/configure.ac
index 29130175..019bdbac 100644
--- a/configure.ac
+++ b/configure.ac
@@ -161,6 +161,7 @@ dnl check for dependencies
 dnl *************************************************
 
 AC_PROG_CXX
+AC_CANONICAL_HOST
 AC_USE_SYSTEM_EXTENSIONS
 AC_PROG_INSTALL
 
@@ -219,6 +220,12 @@ AS_IF([test "x$ac_cv_bad_fts" = "xyes"],
       [CFLAGS="$CFLAGS -DBAD_FTS=1",
        CXXFLAGS="$CXXFLAGS -DBAD_FTS=1"])
 
+dnl On musl, we need to find fts-standalone
+AS_CASE(
+  [${host_os}], [*-musl*], [
+    PKG_CHECK_MODULES([FTS], [fts-standalone])
+])
+
 dnl Check for dependency: libelf, libdw, libebl (elfutils)
 dnl Note that we need to use at least elfutils 0.159 but
 dnl at that time elfutils didnt have pkgconfig capabilities
diff --git a/src/Makefile.am b/src/Makefile.am
index 29da1ecf..1591224f 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -46,12 +46,12 @@ if CTF_READER
 libabigail_la_SOURCES += abg-ctf-reader.cc
 endif
 
-libabigail_la_LIBADD = $(DEPS_LIBS)
+libabigail_la_LIBADD = $(DEPS_LIBS) $(FTS_LIBS)
 libabigail_la_LDFLAGS = -lpthread -Wl,--as-needed -no-undefined
 
 CUSTOM_MACROS = -DABIGAIL_ROOT_SYSTEM_LIBDIR=\"${libdir}\"
 
 AM_CPPFLAGS=\
-$(CUSTOM_MACROS) $(DEPS_CPPFLAGS) \
+$(CUSTOM_MACROS) $(DEPS_CPPFLAGS) $(FTS_CFLAGS) \
 -Wall -I$(abs_top_srcdir) -I$(abs_top_srcdir)/include \
 -I$(abs_top_builddir)/include -I$(abs_top_builddir)
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 648a71b5..f7592b60 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -37,7 +37,8 @@ abicompat_LDADD = $(abs_top_builddir)/src/libabigail.la
 
 abipkgdiff_SOURCES = abipkgdiff.cc
 abipkgdiffdir = $(bindir)
-abipkgdiff_LDADD = $(abs_top_builddir)/src/libabigail.la
+abipkgdiff_CPPFLAGS = $(FTS_CFLAGS)
+abipkgdiff_LDADD = $(abs_top_builddir)/src/libabigail.la $(FTS_LIBS)
 abipkgdiff_LDFLAGS = -pthread
 
 kmidiff_SOURCES = kmidiff.cc
diff --git a/tools/kmidiff.cc b/tools/kmidiff.cc
index b802348f..2e88baa7 100644
--- a/tools/kmidiff.cc
+++ b/tools/kmidiff.cc
@@ -11,7 +11,6 @@
 
 #include <sys/types.h>
 #include <dirent.h>
-#include <fts.h>
 #include <cstring>
 #include <string>
 #include <vector>