new file mode 100644
--- /dev/null
+++ b/lib/xmalloc.c
@@ -0,0 +1,65 @@
+/* xmalloc.c -- malloc with out of memory checking
+   Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+
+   This program 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 2, or (at your option)
+   any later version.
+
+   This program 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 this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
+
+#ifdef STDC_HEADERS
+#include <stdlib.h>
+#else
+char *malloc ();
+char *realloc ();
+void free ();
+#endif
+
+void error ();
+
+/* Allocate N bytes of memory dynamically, with error checking.  */
+
+char *
+xmalloc (n)
+     unsigned n;
+{
+  char *p;
+
+  p = malloc (n);
+  if (p == 0)
+    /* Must exit with 2 for `cmp'.  */
+    error (2, 0, "virtual memory exhausted");
+  return p;
+}
+
+/* Change the size of an allocated block of memory P to N bytes,
+   with error checking.
+   If P is NULL, run xmalloc.
+   If N is 0, run free and return NULL.  */
+
+char *
+xrealloc (p, n)
+     char *p;
+     unsigned n;
+{
+  if (p == 0)
+    return xmalloc (n);
+  if (n == 0)
+    {
+      free (p);
+      return 0;
+    }
+  p = realloc (p, n);
+  if (p == 0)
+    /* Must exit with 2 for `cmp'.  */
+    error (2, 0, "virtual memory exhausted");
+  return p;
+}