gnu: Add libvterm.

* gnu/packages/terminals.scm (libvterm): New variable.

gnu/packages/terminals.scm

@@ -396,3 +396,37 @@ (define-public unibilium
 on curses or any other library.  It also doesn't use global variables, so it
 should be thread-safe.")
     (license license:lgpl3+)))
+
+(define-public libvterm
+  (package
+    (name "libvterm")
+    (version "0+bzr681")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "http://www.leonerd.org.uk/code/libvterm/"
+                           "libvterm-" version ".tar.gz"))
+       (sha256
+        (base32
+         "1s56c8p1qz6frkcri0hg4qyydv2wcccj6n2xmz1dwcdqn38ldsmb"))))
+    (build-system gnu-build-system)
+    (arguments
+     `(#:make-flags
+       (list "CC=gcc"
+             (string-append "PREFIX=" (assoc-ref %outputs "out")))
+       #:test-target "test"
+       #:phases
+       (modify-phases %standard-phases
+         (delete 'configure))))
+    (native-inputs
+     `(("libtool" ,libtool)
+       ("perl" ,perl)))
+    (home-page "http://www.leonerd.org.uk/code/libvterm/")
+    (synopsis "VT220/xterm/ECMA-48 terminal emulator library")
+    (description "Libvterm is an abstract C99 library which implements a VT220
+or xterm-like terminal emulator.  It doesn't use any particular graphics
+toolkit or output system, instead it invokes callback function pointers that
+its embedding program should provide it to draw on its behalf.  It avoids
+calling @code{malloc} during normal running state, allowing it to be used in
+embedded kernel situations.")
+    (license license:expat)))