make the name of the library directory a config option

Introduce new makefile variable lib to hold the name of the lib
directory ("lib" by default).  Also introduce a switch for configure
to specify this name with --with-lib=ARG.  This is useful for systems
that use a different name than "lib" (like "lib64" on some 64 bit
Linux architectures).

Signed-off-by: Robert Schiele <rschiele@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Makefile b/Makefile
index ca1247d..ff5fc5f 100644
--- a/Makefile
+++ b/Makefile
@@ -151,6 +151,7 @@
 else
 sysconfdir = $(prefix)/etc
 endif
+lib = lib
 ETC_GITCONFIG = $(sysconfdir)/gitconfig
 # DESTDIR=
 
@@ -500,9 +501,9 @@
 
 ifndef NO_CURL
 	ifdef CURLDIR
-		# Try "-Wl,-rpath=$(CURLDIR)/lib" in such a case.
+		# Try "-Wl,-rpath=$(CURLDIR)/$(lib)" in such a case.
 		BASIC_CFLAGS += -I$(CURLDIR)/include
-		CURL_LIBCURL = -L$(CURLDIR)/lib $(CC_LD_DYNPATH)$(CURLDIR)/lib -lcurl
+		CURL_LIBCURL = -L$(CURLDIR)/$(lib) $(CC_LD_DYNPATH)$(CURLDIR)/$(lib) -lcurl
 	else
 		CURL_LIBCURL = -lcurl
 	endif
@@ -520,7 +521,7 @@
 
 ifdef ZLIB_PATH
 	BASIC_CFLAGS += -I$(ZLIB_PATH)/include
-	EXTLIBS += -L$(ZLIB_PATH)/lib $(CC_LD_DYNPATH)$(ZLIB_PATH)/lib
+	EXTLIBS += -L$(ZLIB_PATH)/$(lib) $(CC_LD_DYNPATH)$(ZLIB_PATH)/$(lib)
 endif
 EXTLIBS += -lz
 
@@ -528,7 +529,7 @@
 	OPENSSL_LIBSSL = -lssl
 	ifdef OPENSSLDIR
 		BASIC_CFLAGS += -I$(OPENSSLDIR)/include
-		OPENSSL_LINK = -L$(OPENSSLDIR)/lib $(CC_LD_DYNPATH)$(OPENSSLDIR)/lib
+		OPENSSL_LINK = -L$(OPENSSLDIR)/$(lib) $(CC_LD_DYNPATH)$(OPENSSLDIR)/$(lib)
 	else
 		OPENSSL_LINK =
 	endif
@@ -545,7 +546,7 @@
 ifdef NEEDS_LIBICONV
 	ifdef ICONVDIR
 		BASIC_CFLAGS += -I$(ICONVDIR)/include
-		ICONV_LINK = -L$(ICONVDIR)/lib $(CC_LD_DYNPATH)$(ICONVDIR)/lib
+		ICONV_LINK = -L$(ICONVDIR)/$(lib) $(CC_LD_DYNPATH)$(ICONVDIR)/$(lib)
 	else
 		ICONV_LINK =
 	endif
diff --git a/configure.ac b/configure.ac
index b2f1965..84fd7f1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -69,6 +69,17 @@
 ## Site configuration related to programs (before tests)
 ## --with-PACKAGE[=ARG] and --without-PACKAGE
 #
+# Set lib to alternative name of lib directory (e.g. lib64)
+AC_ARG_WITH([lib],
+ [AS_HELP_STRING([--with-lib=ARG],
+                 [ARG specifies alternative name for lib directory])],
+ [if test "$withval" = "no" -o "$withval" = "yes"; then \
+	AC_MSG_WARN([You should provide name for --with-lib=ARG]); \
+else \
+	GIT_CONF_APPEND_LINE(lib=$withval); \
+fi; \
+],[])
+#
 # Define SHELL_PATH to provide path to shell.
 GIT_ARG_SET_PATH(shell)
 #