AUTOTOOLS: Refactor unicode library detection

If $libdir is not in default library path libunistring cannot be
found. (pkg-config can not be used in this case).
This patch helps to search libunistring in "$libdir" directory.

In refactoring part, indentation was updated to be more readable
and some duplicated parts were removed.

3 files changed, 45 insertions, 15 deletions

diff --git a/configure.ac b/configure.ac
index 39f6a3197..cdf46d4c7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -157,16 +157,15 @@ m4_include([src/external/libndr_nbt.m4])
 
 WITH_UNICODE_LIB
 if test x$unicode_lib = xlibunistring; then
-	m4_include([src/external/libunistring.m4])
-	        AC_DEFINE_UNQUOTED(HAVE_LIBUNISTRING, 1, [Using libunistring for unicode])
-	        UNICODE_LIBS=-lunistring
-	        AC_SUBST(UNICODE_LIBS)
+    m4_include([src/external/libunistring.m4])
+    AC_DEFINE_UNQUOTED(HAVE_LIBUNISTRING, 1, [Using libunistring for unicode])
+    UNICODE_LIBS=$UNISTRING_LIBS
 else
-	m4_include([src/external/glib.m4])
-	        AC_DEFINE_UNQUOTED(HAVE_GLIB2, 1, [Using libunistring for unicode])
-	        UNICODE_LIBS=$GLIB2_LIBS
-	        AC_SUBST(UNICODE_LIBS)
+    m4_include([src/external/glib.m4])
+    AC_DEFINE_UNQUOTED(HAVE_GLIB2, 1, [Using glib2 for unicode])
+    UNICODE_LIBS=$GLIB2_LIBS
 fi
+AC_SUBST(UNICODE_LIBS)
 
 WITH_LIBNL
 
diff --git a/src/build_macros.m4 b/src/build_macros.m4
index 8cd2d3cde..92d7c65d1 100644
--- a/src/build_macros.m4
+++ b/src/build_macros.m4
@@ -34,3 +34,17 @@ $3
 ])dnl
 fi[]dnl
 ])])
+
+dnl SSS_AC_EXPAND_LIB_DIR() prepare variable sss_extra_libdir,
+dnl variable will contain expanded version of string "$libdir"
+dnl therefore this variable can be safely added to LDFLAGS as
+dnl "-L$sss_extra_libdir ".
+AC_DEFUN([SSS_AC_EXPAND_LIB_DIR],
+[
+    AC_REQUIRE([AC_LIB_PREPARE_PREFIX])
+    dnl By default, look in $includedir and $libdir.
+    AC_LIB_WITH_FINAL_PREFIX([
+        eval additional_libdir=\"$libdir\"
+    ])
+    sss_extra_libdir="$additional_libdir"
+])
diff --git a/src/external/libunistring.m4 b/src/external/libunistring.m4
index 18ea3e62a..bbc92b332 100644
--- a/src/external/libunistring.m4
+++ b/src/external/libunistring.m4
@@ -1,14 +1,31 @@
-AC_CHECK_HEADERS(unistr.h,
-    [AC_CHECK_LIB([unistring], [u8_strlen], [ UNISTRING_LIBS="-lunistring" ], [AC_MSG_ERROR([No usable libunistring library found])])],
+SSS_AC_EXPAND_LIB_DIR()
+
+AC_CHECK_HEADERS([unistr.h],
+    [AC_CHECK_LIB([unistring],
+                  [u8_strlen],
+                  [UNISTRING_LIBS="-lunistring"],
+                  [AC_MSG_ERROR([No usable libunistring library found])],
+                  [-L$sss_extra_libdir])],
     [AC_MSG_ERROR([libunistring header files are not installed])]
 )
 
-AC_CHECK_HEADERS(unicase.h,
-    [AC_CHECK_LIB([unistring], [u8_casecmp], [ UNISTRING_LIBS="-lunistring" ], [AC_MSG_ERROR([No usable libunistring library found])])],
+AC_CHECK_HEADERS([unicase.h],
+    [AC_CHECK_LIB([unistring],
+                  [u8_casecmp],
+                  [UNISTRING_LIBS="-lunistring"],
+                  [AC_MSG_ERROR([No usable libunistring library found])],
+                  [-L$sss_extra_libdir])],
     [AC_MSG_ERROR([libunistring header files are not installed])]
 )
 
-AC_CHECK_HEADERS(unistr.h,
-    [AC_CHECK_LIB([unistring], [u8_check], [ UNISTRING_LIBS="-lunistring" ], [AC_MSG_ERROR([No usable libunistring library found])])],
+AC_CHECK_HEADERS([unistr.h],
+    [AC_CHECK_LIB([unistring],
+                  [u8_check],
+                  [UNISTRING_LIBS="-lunistring"],
+                  [AC_MSG_ERROR([No usable libunistring library found])],
+                  [-L$sss_extra_libdir])],
     [AC_MSG_ERROR([libunistring header files are not installed])]
-)
\ No newline at end of file
+)
+
+
+UNISTRING_LIBS="-L$sss_extra_libdir $UNISTRING_LIBS "