distro: Add GNU Readline.

* distro/base.scm (readline): New variable.
  (guile-1.8, guile-2.0): Use it.

* distro/readline-link-ncurses.patch: New file.
* Makefile.am (nobase_dist_guilemodule_DATA): Add it.

Makefile.am

@@ -39,7 +39,8 @@ nobase_dist_guilemodule_DATA =			\
   $(MODULES)					\
   distro/guile-1.8-cpp-4.5.patch		\
   distro/m4-readlink-EINVAL.patch		\
-  distro/m4-s_isdir.patch
+  distro/m4-s_isdir.patch			\
+  distro/readline-link-ncurses.patch
 
 nobase_nodist_guilemodule_DATA = $(GOBJECTS)
 

distro/base.scm

@@ -198,6 +198,40 @@ faster algorithms.")
    (license "LGPLv3+")
    (home-page "http://gmplib.org/")))
 
+(define-public readline
+  (package
+   (name "readline")
+   (version "6.2")
+   (source (origin
+            (method http-fetch)
+            (uri (string-append "http://ftp.gnu.org/gnu/readline/readline-"
+                                version ".tar.gz"))
+            (sha256
+             (base32
+              "10ckm2bd2rkxhvdmj7nmbsylmihw0abwcsnxf8y27305183rd9kr"))))
+   (build-system gnu-build-system)
+   (propagated-inputs `(("ncurses" ,(nixpkgs-derivation* "ncurses"))))
+   (inputs `(("patch/link-ncurses"
+              ,(search-path %load-path
+                            "distro/readline-link-ncurses.patch"))))
+   (arguments `(#:patches (list (assoc-ref %build-inputs
+                                           "patch/link-ncurses"))
+                #:patch-flags '("-p0")))
+   (description "GNU Readline, a library for interactive line editing")
+   (long-description
+    "The GNU Readline library provides a set of functions for use by
+applications that allow users to edit command lines as they are typed in.
+Both Emacs and vi editing modes are available.  The Readline library includes
+additional functions to maintain a list of previously-entered command lines,
+to recall and perhaps reedit those lines, and perform csh-like history
+expansion on previous commands.
+
+The history facilites are also placed into a separate library, the History
+library, as part of the build process.  The History library may be used
+without Readline in applications which desire its capabilities.")
+   (license "GPLv3+")
+   (home-page "http://savannah.gnu.org/projects/readline/")))
+
 (define-public libtool
   (package
    (name "libtool")
@@ -290,7 +324,7 @@ internal in-memory representation.")
    (inputs `(("patch/snarf"
               ,(search-path %load-path "distro/guile-1.8-cpp-4.5.patch"))
              ("gawk" ,gawk)
-             ("readline" ,(nixpkgs-derivation* "readline"))))
+             ("readline" ,readline)))
 
    ;; Since `guile-1.8.pc' has "Libs: ... -lgmp -lltdl", these must be
    ;; propagated.
@@ -323,7 +357,7 @@ extensible.  It supports many SRFIs.")
    (native-inputs `(("xz" ,(nixpkgs-derivation* "xz"))
                     ("pkgconfig" ,(nixpkgs-derivation* "pkgconfig"))))
    (inputs `(("libffi" ,(nixpkgs-derivation* "libffi"))
-             ("readline" ,(nixpkgs-derivation* "readline"))))
+             ("readline" ,readline)))
 
    (propagated-inputs
     `( ;; These ones aren't normally needed here, but since `libguile-2.0.la'

distro/readline-link-ncurses.patch

@@ -0,0 +1,18 @@
+This patch is to make sure that `libncurses' is among the `NEEDED'
+dependencies of `libreadline.so' and `libhistory.so'.
+
+Failing to do that, applications linking against Readline are
+forced to explicitly link against libncurses as well; in addition,
+this trick doesn't work when using GNU ld's `--as-needed'.
+
+--- shlib/Makefile.in	2009-01-06 18:03:22.000000000 +0100
++++ shlib/Makefile.in	2009-07-27 14:43:25.000000000 +0200
+@@ -84,7 +84,7 @@ SHOBJ_LDFLAGS = @SHOBJ_LDFLAGS@
+ SHOBJ_XLDFLAGS = @SHOBJ_XLDFLAGS@
+ SHOBJ_LIBS = @SHOBJ_LIBS@
+ 
+-SHLIB_XLDFLAGS = @LDFLAGS@ @SHLIB_XLDFLAGS@
++SHLIB_XLDFLAGS = @LDFLAGS@ @SHLIB_XLDFLAGS@ -lncurses
+ SHLIB_LIBS = @SHLIB_LIBS@
+ 
+ SHLIB_DOT = @SHLIB_DOT@