Functions for mpn <-> mpz conversions.

1 files changed, 85 insertions, 0 deletions

diff --git a/gmp-glue.h b/gmp-glue.h
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+++ b/gmp-glue.h
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+/* gmp-glue.h */
+
+/* nettle, low-level cryptographics library
+ *
+ * Copyright (C) 2013 Niels Möller
+ *  
+ * The nettle library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 of the License, or (at your
+ * option) any later version.
+ * 
+ * The nettle library 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 Lesser General Public
+ * License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with the nettle library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ * MA 02111-1301, USA.
+ */
+
+#ifndef NETTLE_GMP_GLUE_H_INCLUDED
+#define NETTLE_GMP_GLUE_H_INCLUDED
+
+#include <gmp.h>
+
+/* Name mangling. */
+#define _mpz_cmp_limbs _nettle_mpz_cmp_limbs
+#define _mpz_read_limbs _nettle_mpz_read_limbs
+#define _mpz_read_limbs_n _nettle_mpz_read_limbs_n
+#define _mpz_copy_limbs _nettle_mpz_copy_limbs
+#define _mpz_write_limbs _nettle_mpz_write_limbs
+#define _mpz_modify_limbs _nettle_mpz_modify_limbs
+#define _mpz_done_limbs _nettle_mpz_done_limbs
+#define _mpz_init_mpn _nettle_mpz_init_mpn
+
+/* Some functions for interfacing between mpz and mpn code. Signs of
+   the mpz numbers are generally ignored. */
+
+int
+_mpz_cmp_limbs (mpz_srcptr a, const mp_limb_t *bp, mp_size_t bn);
+
+/* Read access to mpz numbers. */
+
+/* Return limb pointer, for read-only operations. Use mpz_size to get
+   the number of limbs. */
+const mp_limb_t *
+_mpz_read_limbs (const mpz_srcptr x);
+
+/* Get a pointer to an n limb area, for read-only operation. n must be
+   greater or equal to the current size, and the mpz is zero-padded if
+   needed. */
+const mp_limb_t *
+_mpz_read_limbs_n (mpz_ptr x, mp_size_t n);
+
+/* Copy limbs, with zero-padding. */
+/* FIXME: Reorder arguments, on the theory that the first argument of
+   an _mpz_* fucntion should be an mpz_t? Or rename to _mpz_get_limbs,
+   with argument order consistent with mpz_get_*. */
+void
+_mpz_copy_limbs (mp_limb_t *xp, mpz_srcptr x, mp_size_t n);
+
+/* Write access to mpz numbers. */
+
+/* Get a limb pointer for writing, previous contents may be
+   destroyed. */
+mp_limb_t *
+_mpz_write_limbs (mpz_ptr x, mp_size_t n);
+
+/* Get a limb pointer for writing, previous contents is intact. */
+mp_limb_t *
+_mpz_modify_limbs (mpz_ptr x, mp_size_t n);
+
+/* Update size. */
+void
+_mpz_done_limbs (mpz_ptr x, mp_size_t n);
+
+
+/* Using an mpn number as an mpz. Can be used for read-only access
+   only. x must not be cleared or reallocated. */
+mpz_srcptr
+_mpz_init_mpn (mpz_ptr x, const mp_limb_t *xp, mp_size_t xs);
+
+#endif /* NETTLE_GMP_GLUE_H_INCLUDED */