/* -*-c-*-
*
- * $Id: mp-io.c,v 1.2 1999/11/19 13:19:06 mdw Exp $
+ * $Id: mp-io.c,v 1.6 2002/10/20 01:12:31 mdw Exp $
*
* Loading and storing of multiprecision integers
*
/*----- Revision history --------------------------------------------------*
*
* $Log: mp-io.c,v $
+ * Revision 1.6 2002/10/20 01:12:31 mdw
+ * Two's complement I/O fixes.
+ *
+ * Revision 1.5 2002/10/06 22:52:50 mdw
+ * Pile of changes for supporting two's complement properly.
+ *
+ * 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.
*
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
+ *
+ * Returns: The number of bits required to represent @m@.
+ *
+ * Use: Calculates the external storage required for a multiprecision
+ * integer.
+ */
+
+unsigned long mp_bits(const mp *m)
+{
+ unsigned long bits;
+ MPX_BITS(bits, m->v, m->vl);
+ return (bits);
+}
+
/* --- @mp_loadl@ --- *
*
* Arguments: @mp *d@ = destination
mp *mp_loadl(mp *d, const void *pv, size_t sz)
{
- MP_MODIFY(d, MPW_RQ(sz));
+ MP_DEST(d, MPW_RQ(sz), MP_UNDEF);
mpx_loadl(d->v, d->vl, pv, sz);
d->f &= ~(MP_UNDEF | MP_NEG);
mp_shrink(d);
mp *mp_loadb(mp *d, const void *pv, size_t sz)
{
- MP_MODIFY(d, MPW_RQ(sz));
+ MP_DEST(d, MPW_RQ(sz), MP_UNDEF);
mpx_loadb(d->v, d->vl, pv, sz);
d->f &= ~(MP_UNDEF | MP_NEG);
mp_shrink(d);
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 (m->f & MP_NEG)
+ 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 (m->f & MP_NEG)
+ mpx_storeb2cn(m->v, m->vl, pv, sz);
+ else
+ mpx_storeb(m->v, m->vl, pv, sz);
+}
+
/*----- That's all, folks -------------------------------------------------*/