distro: Add GNU Cpio.

* distro/packages/cpio.scm,
  distro/packages/patches/cpio-gets-undeclared.patch: New files.
* Makefile.am (MODULES): Add 'cpio.scm'.
  (dist_patch_DATA): Add 'cpio-gets-undeclared.patch'.

Makefile.am

@@ -48,6 +48,7 @@ MODULES =					\
   distro/packages/bison.scm			\
   distro/packages/bootstrap.scm			\
   distro/packages/compression.scm		\
+  distro/packages/cpio.scm			\
   distro/packages/ddrescue.scm			\
   distro/packages/ed.scm			\
   distro/packages/flex.scm			\
@@ -92,6 +93,7 @@ nobase_dist_guilemodule_DATA = $(MODULES)
 patchdir = $(guilemoduledir)/distro/packages/patches
 dist_patch_DATA =						\
   distro/packages/patches/binutils-ld-new-dtags.patch		\
+  distro/packages/patches/cpio-gets-undeclared.patch		\
   distro/packages/patches/diffutils-gets-undeclared.patch	\
   distro/packages/patches/flex-bison-tests.patch		\
   distro/packages/patches/gettext-gets-undeclared.patch		\

distro/packages/cpio.scm

@@ -0,0 +1,57 @@
+;;; Guix --- Nix package management from Guile.         -*- coding: utf-8 -*-
+;;; Copyright (C) 2012 Nikita Karetnikov <nikita@karetnikov.org>
+;;;
+;;; This file is part of Guix.
+;;;
+;;; Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (distro packages cpio)
+  #:use-module (distro)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu))
+
+(define-public cpio
+  (package
+    (name "cpio")
+    (version "2.11")
+    (source
+     (origin
+      (method url-fetch)
+      (uri (string-append "mirror://gnu/cpio/cpio-"
+                          version ".tar.bz2"))
+      (sha256
+       (base32
+        "1gavgpzqwgkpagjxw72xgxz52y1ifgz0ckqh8g7cckz7jvyhp0mv"))))
+    (build-system gnu-build-system)
+    (arguments
+     `(#:patches (list (assoc-ref %build-inputs
+                                  "patch/gets"))))
+    (inputs
+     `(("patch/gets" ,(search-patch "cpio-gets-undeclared.patch"))))
+    (home-page "https://www.gnu.org/software/cpio/")
+    (synopsis
+     "A program to create or extract from cpio archives")
+    (description
+     "GNU Cpio copies files into or out of a cpio or tar archive. The
+archive can be another file on the disk, a magnetic tape, or a pipe.
+
+GNU Cpio supports the following archive formats: binary, old ASCII, new
+ASCII, crc, HPUX binary, HPUX old ASCII, old tar, and POSIX.1 tar. The
+tar format is provided for compatability with the tar program. By
+default, cpio creates binary format archives, for compatibility with
+older cpio programs. When extracting from archives, cpio automatically
+recognizes which kind of archive it is reading and can read archives
+created on machines with a different byte-order.")
+    (license "GPLv3+")))

distro/packages/patches/cpio-gets-undeclared.patch

@@ -0,0 +1,45 @@
+This patch is needed to allow builds with newer versions of
+the GNU libc (2.16+).
+
+The upstream fix was:
+
+  commit 66712c23388e93e5c518ebc8515140fa0c807348
+  Author: Eric Blake <eblake@redhat.com>
+  Date:   Thu Mar 29 13:30:41 2012 -0600
+
+      stdio: don't assume gets any more
+
+      Gnulib intentionally does not have a gets module, and now that C11
+      and glibc have dropped it, we should be more proactive about warning
+      any user on a platform that still has a declaration of this dangerous
+      interface.
+
+      * m4/stdio_h.m4 (gl_STDIO_H, gl_STDIO_H_DEFAULTS): Drop gets
+      support.
+      * modules/stdio (Makefile.am): Likewise.
+      * lib/stdio-read.c (gets): Likewise.
+      * tests/test-stdio-c++.cc: Likewise.
+      * m4/warn-on-use.m4 (gl_WARN_ON_USE_PREPARE): Fix comment.
+      * lib/stdio.in.h (gets): Make warning occur in more places.
+      * doc/posix-functions/gets.texi (gets): Update documentation.
+      Reported by Christer Solskogen.
+
+      Signed-off-by: Eric Blake <eblake@redhat.com>
+
+This patch just gets rid of the offending part.
+
+--- cpio-2.11/gnu/stdio.in.h-orig	2012-11-25 22:17:06.000000000 +0400
++++ cpio-2.11/gnu/stdio.in.h		2012-11-25 22:18:36.000000000 +0400
+@@ -135,12 +135,6 @@
+                  "use gnulib module fflush for portable POSIX compliance");
+ #endif
+ 
+-/* It is very rare that the developer ever has full control of stdin,
+-   so any use of gets warrants an unconditional warning.  Assume it is
+-   always declared, since it is required by C89.  */
+-#undef gets
+-_GL_WARN_ON_USE (gets, "gets is a security hole - use fgets instead");
+-
+ #if @GNULIB_FOPEN@
+ # if @REPLACE_FOPEN@
+ #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)