X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/d34decd2b2b88240cf4ca68a2a5feb7bf36de6e7..813390c45f438f411662b1a55678e63f11681eb4:/mp-io.c

diff --git a/mp-io.c b/mp-io.c
index c510649..9639a99 100644
--- a/mp-io.c
+++ b/mp-io.c
@@ -1,13 +1,13 @@
 /* -*-c-*-
  *
- * $Id: mp-io.c,v 1.4 2000/06/17 11:45:09 mdw Exp $
+ * $Id$
  *
  * Loading and storing of multiprecision integers
  *
  * (c) 1999 Straylight/Edgeware
  */
 
-/*----- Licensing notice --------------------------------------------------* 
+/*----- Licensing notice --------------------------------------------------*
  *
  * This file is part of Catacomb.
  *
@@ -15,37 +15,18 @@
  * it under the terms of the GNU Library General Public License as
  * published by the Free Software Foundation; either version 2 of the
  * License, or (at your option) any later version.
- * 
+ *
  * Catacomb 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 Library General Public License for more details.
- * 
+ *
  * You should have received a copy of the GNU Library General Public
  * License along with Catacomb; if not, write to the Free
  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  * MA 02111-1307, USA.
  */
 
-/*----- Revision history --------------------------------------------------* 
- *
- * $Log: mp-io.c,v $
- * Revision 1.4  2000/06/17 11:45:09  mdw
- * Major memory management overhaul.  Added arena support.  Use the secure
- * arena for secret integers.  Replace and improve the MP management macros
- * (e.g., replace MP_MODIFY by MP_DEST).
- *
- * Revision 1.3  1999/11/21 22:13:02  mdw
- * Add mp version of MPX_BITS.
- *
- * Revision 1.2  1999/11/19 13:19:06  mdw
- * Set flags on results correctly.
- *
- * Revision 1.1  1999/11/17 18:02:16  mdw
- * New multiprecision integer arithmetic suite.
- *
- */
-
 /*----- Header files ------------------------------------------------------*/
 
 #include "mp.h"
@@ -69,6 +50,23 @@ size_t mp_octets(const mp *m)
   return (sz);
 }
 
+/* --- @mp_octets2c@ --- *
+ *
+ * Arguments:	@const mp *m@ = a multiprecision integer
+ *
+ * Returns:	The number of octets required to represent @m@.
+ *
+ * Use:		Calculates the external storage required for a multiprecision
+ *		integer represented as two's complement.
+ */
+
+size_t mp_octets2c(const mp *m)
+{
+  size_t sz;
+  MPX_OCTETS2C(sz, m->v, m->vl);
+  return (sz);
+}
+
 /* --- @mp_bits@ --- *
  *
  * Arguments:	@const mp *m@ = a multiprecision integer
@@ -176,4 +174,108 @@ void mp_storeb(const mp *m, void *pv, size_t sz)
   mpx_storeb(m->v, m->vl, pv, sz);
 }
 
+/* --- @mp_loadl2c@ --- *
+ *
+ * Arguments:	@mp *d@ = destination
+ *		@const void *pv@ = pointer to source data
+ *		@size_t sz@ = size of the source data
+ *
+ * Returns:	Resulting multiprecision number.
+ *
+ * Use:		Loads a multiprecision number from an array of octets as
+ *		two's complement.  The first byte in the array is the least
+ *		significant.
+ */
+
+mp *mp_loadl2c(mp *d, const void *pv, size_t sz)
+{
+  const octet *ov = pv;
+  MP_DEST(d, MPW_RQ(sz), MP_UNDEF);
+  if (!sz || !(ov[sz - 1] & 0x80)) {
+    mpx_loadl(d->v, d->vl, pv, sz);
+    d->f &= ~MP_NEG;
+  } else {
+    mpx_loadl2cn(d->v, d->vl, pv, sz);
+    d->f |= MP_NEG;
+  }
+  d->f &= ~MP_UNDEF;
+  mp_shrink(d);
+  return (d);
+}
+
+/* --- @mp_storel2c@ --- *
+ *
+ * Arguments:	@const mp *m@ = source
+ *		@void *pv@ = pointer to output array
+ *		@size_t sz@ = size of the output array
+ *
+ * Returns:	---
+ *
+ * Use:		Stores a multiprecision number in an array of octets as two's
+ *		complement.  The first byte in the array is the least
+ *		significant.  If the array is too small to represent the
+ *		number, high-order bits are truncated; if the array is too
+ *		large, high order bytes are sign-extended.
+ */
+
+void mp_storel2c(const mp *m, void *pv, size_t sz)
+{
+  if (MP_NEGP(m))
+    mpx_storel2cn(m->v, m->vl, pv, sz);
+  else
+    mpx_storel(m->v, m->vl, pv, sz);
+}
+
+/* --- @mp_loadb2c@ --- *
+ *
+ * Arguments:	@mp *d@ = destination
+ *		@const void *pv@ = pointer to source data
+ *		@size_t sz@ = size of the source data
+ *
+ * Returns:	Resulting multiprecision number.
+ *
+ * Use:		Loads a multiprecision number from an array of octets as
+ *		two's complement.  The last byte in the array is the least
+ *		significant.
+ */
+
+mp *mp_loadb2c(mp *d, const void *pv, size_t sz)
+{
+  const octet *ov = pv;
+  MP_DEST(d, MPW_RQ(sz), MP_UNDEF);
+  if (!sz || !(ov[0] & 0x80)) {
+    mpx_loadb(d->v, d->vl, pv, sz);
+    d->f &= ~MP_NEG;
+  } else {
+    mpx_loadb2cn(d->v, d->vl, pv, sz);
+    d->f |= MP_NEG;
+  }
+  d->f &= ~MP_UNDEF;
+  mp_shrink(d);
+  return (d);
+}
+
+/* --- @mp_storeb2c@ --- *
+ *
+ * Arguments:	@const mp *m@ = source
+ *		@void *pv@ = pointer to output array
+ *		@size_t sz@ = size of the output array
+ *
+ * Returns:	---
+ *
+ * Use:		Stores a multiprecision number in an array of octets, as
+ *		two's complement.  The last byte in the array is the least
+ *		significant.  If the array is too small to represent the
+ *		number, high-order bits are truncated; if the array is too
+ *		large, high order bytes are sign-extended.
+ */
+
+void mp_storeb2c(const mp *m, void *pv, size_t sz)
+{
+  if (MP_NEGP(m))
+    mpx_storeb2cn(m->v, m->vl, pv, sz);
+  else
+    mpx_storeb(m->v, m->vl, pv, sz);
+}
+
 /*----- That's all, folks -------------------------------------------------*/