Files
RedBear-OS/local/recipes/libs/libgcrypt/source/mpi/generic/mpih-lshift.c
T
vasilito c825f470cb
redbear-ci / check (push) Has been cancelled
libs: vendor libgcrypt 1.11.1 + libgpg-error 1.55; wire into kf6-kwallet
kf6-kwallet's kwalletbackend hard-requires LibGcrypt 1.5.0 for PBKDF2 key
derivation and the GPG-backed wallet format. Vendor both libraries under the
full-fork model (committed source/, offline-reproducible) and add libgcrypt to
kf6-kwallet's dependencies.

Release tarballs ship a pre-generated configure and a config.sub that already
recognises the *-redox triple, so no autotools regeneration is needed at cook
time. libgpg-error supplies a generic pthread-backed gpgrt_lock_t for Redox via
its build script; the test-only redox.patch (tms/times stub) is baked into
libgcrypt's source and kept alongside for future version bumps.

Promoted from the stale recipes/wip copies (now .disabled).
2026-08-02 04:29:16 +03:00

69 lines
2.1 KiB
C

/* mpi-lshift.c - MPI helper functions
* Copyright (C) 1994, 1996, 1998, 2001, 2002 Free Software Foundation, Inc.
*
* This file is part of Libgcrypt.
*
* Libgcrypt 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.
*
* Libgcrypt 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 this program; if not, see <https://www.gnu.org/licenses/>.
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* Note: This code is heavily based on the GNU MP Library.
* Actually it's the same code with only minor changes in the
* way the data is stored; this is to support the abstraction
* of an optional secure memory allocation which may be used
* to avoid revealing of sensitive data due to paging etc.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include "mpi-internal.h"
/* Shift U (pointed to by UP and USIZE digits long) CNT bits to the left
* and store the USIZE least significant digits of the result at WP.
* Return the bits shifted out from the most significant digit.
*
* Argument constraints:
* 1. 0 < CNT < BITS_PER_MP_LIMB
* 2. If the result is to be written over the input, WP must be >= UP.
*/
mpi_limb_t
_gcry_mpih_lshift( mpi_ptr_t wp, mpi_ptr_t up, mpi_size_t usize,
unsigned int cnt)
{
mpi_limb_t high_limb, low_limb;
unsigned sh_1, sh_2;
mpi_size_t i;
mpi_limb_t retval;
sh_1 = cnt;
wp += 1;
sh_2 = BITS_PER_MPI_LIMB - sh_1;
i = usize - 1;
low_limb = up[i];
retval = low_limb >> sh_2;
high_limb = low_limb;
while ( --i >= 0 )
{
low_limb = up[i];
wp[i] = (high_limb << sh_1) | (low_limb >> sh_2);
high_limb = low_limb;
}
wp[i] = high_limb << sh_1;
return retval;
}